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Abstract. This paper explores the similarities and differences between two prominent problems in ... mathematical relation between the BCF and the. IPBE, and ...... Table 3. Pairwise comparison within N number of elements. N1. N2. N3. N4. NI. N1. 1 … … ..... A survey was used to find answers to the research questions and.
IN THE NAME OF ALLAH, THE MERCIFUL, THE MERCY-GIVING

JKAU: Eng. Sci., Vol. 28 No. 2, 101 Pages (1438 A.H./ 2017 A.D.) ISSN 1319-1047 Legal Deposit: 0300/14

Journal of KING ABDULAZIZ UNIVERSITY

Engineering Sciences Volume 28 Number 2 2017 A.D. 1438 A.H.

Scientific Publishing Center King Abdulaziz University P.O. Box 80200, Jeddah 21589 Saudi Arabia http://spc.kau.edu.sa

Editorial Board Prof. Abdulrahim Ahmed Al-Zahrani

Editor in Chief

[email protected]

Prof. Majed Moalla Hassan Alhazmy

Member

[email protected]

Prof. Mostafa Abbas Hamed Mohamed

Member

[email protected]

Prof. Ali Muhammad Ali Rushdi

Member

[email protected] & [email protected]

Prof. Abdulraheim H Al-Zahrani

Member

[email protected]

Prof. Reda Mohamed Said Abdulaal [email protected]

Member

JKAU: Eng. Sci., Vol. 28 No. 2, 101 Pages. (1438 A.H./ 2017 A.D.)

Contents English Section Page

Electrical & Computer Engineering  On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations. Ali M. Rushdi and Ahmed S. Balamesh …………………...……….………….

3

Chemical and Material Engineering  Development of Tribological Performance for Epoxy Composites. A. M. M. Al Owad and A. M. Samy ………………………………………….

13

Industrial Engineering  The Importance of Social Media in Education and Prioritizing Process. Alaa Kutbi1 and Madani Alomar .…….……………………………….…….….  Entrepreneurship and Competencies.

Saudi

Engineering

Students:

Intentions

27

and

Hemaid Alsulami …………………………………………………………....

39

 An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study. Ahmed M. Badeeb, Reda M.S. Abdulaal and Abdullah O. Bafail ……….…...

51

Arabic Section Electrical & Computer Engineering  Optimal Dispatch for Hybrid Photovoltaic System. (English Abstract) Taha Jabban, Mohammed Aref Nema and Ahmad Ayoubi ………….……….

101

Electrical & Computer Engineering

JKAU: Eng. Sci., Vol. 28 No. 2, pp: 3 – 9 (1438 A.H./ 2017 A.D.) Doi: 10.4197/Eng. 28-2.1

On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations Ali M. Rushdi and Ahmed S. Balamesh Department of Electrical and Computer Engineering, Faculty of Engineering, King Abdulaziz University, P. O. Box 80204, Jeddah 21589, Saudi Arabia [email protected] Abstract. This paper explores the similarities and differences between two prominent problems in the mathematics of Boolean functions. The first of these problems is that of Boolean curve fitting (BCF), also known as Boolean interpolation, which deals with constructing a curve 𝑧 = 𝑓(𝐗) through a number of points z𝑘 = 𝑓(𝐗 𝑘 ) where 𝑘 = 1,2, … , 𝑚. The second problem is the Inverse Problem of Boolean equations (IPBE), which constructs a Boolean function whose zeroes are all known. While the problem of Boolean curve fitting might require a consistency condition for its solution, the Inverse Problem of Boolean equations might use a consistency condition as an input. Without a consistency condition, the Inverse Problem of Boolean equations can be viewed as a special case of the problem of Boolean curve fitting, provided the specified points z𝑘 are the only zeros of 𝑓(𝐗). Our findings are illustrated via a detailed typical example. Keywords: Boolean curve fitting, Inverse problem, Boolean equations, Consistency condition, Uniqueness, Particular solutions.

The two problems are seemingly identical. So, exposing the subtle differences between them is of interest. Our comparison is a part of an ongoing effort [10,13] to transfer these two problems from the domain of pure mathematics to the reach of engineers and problem solvers. The solutions of the two problems are being converted from declarative specifications (mathematical approach) to constructive procedures (engineering approach).

1. Introduction The problem of Boolean curve fitting (BCF), also known as Boolean interpolation, remained a pure mathematical curiosity with no view of practical applications for almost one century. Most notable among the early contributions to this problem are those due to Stamm [1], McKinsey [2, 3], Ellis [4, 5], and Scognamiglio [6] . Such contributions culminated in the classical treatise by Rudeanu [7] in 1974. A sequel paper by Melter and Rudeanu [8] in 1984 specialized the results in [7] for Boolean functions that are linear in the sense of Löwenheim [9]. Boolean curve fitting witnessed a recent revival [10], as it finally found a useful engineering application in the area of cryptography [11, 12].

The work of Rushdi and Albarakati [13] is related to Boolean interpolation, essentially as a special case, since it deals with the Inverse Problem of Boolean equations (IPBE), in which a Boolean function 𝑓(𝐗) is required to have the same value of 0 (or 1) at (and only at)

3

4

Ali M. Rushdi and Ahmed S. Balamesh

𝑋𝑖 , 𝑎 𝑋𝑖 𝑖 = 𝑋𝑖 ⊙ 𝑎𝑖 = { ̅ 𝑋𝑖 ,

several distinct points 𝐗 = 𝐗 𝑘 . However, the techniques used in [13] are not derived from or based on concepts of Boolean interpolation. The organization of the remainder of this paper is as follows. Sections 2 and 3 review the available results on the BCF and the IPBE, respectively. Section 4 presents the mathematical relation between the BCF and the IPBE, and explains the deep similarities and subtle differences between them. Section 5 supports and clarifies the findings of Section 4 via a demonstrative example. Section 6 concludes the paper. In this section, we reproduce from Rudeanu [7] and Rushdi and Balamesh [10] the main results known on Boolean curve fitting. The problem at hand requires the determination of a Boolean curve whose graph passes through 𝑚 given points (𝐗1 , 𝑧1 ), (𝐗 2 , 𝑧2 ), … , (𝐗 𝑚 , 𝑧𝑚 ) of the Boolean space 𝐵 𝑛 × 𝐵 = 𝐵 𝑛+1, where 𝑇

𝐗 𝑘 = [𝑋𝑘,1 , 𝑋𝑘,2 , … , 𝑋𝑘,𝑛 ] ∈ 𝐵𝑛 , 𝑘 = 1, 2, … , 𝑚

and 𝑧𝑘 ∈ 𝐵, 𝑘 = 1, 2, … , 𝑚.

This is equivalent to finding an interpolating Boolean function 𝑓: 𝐵 𝑛 → 𝐵 such that 𝑓(𝐗 𝑘 ) = 𝑧𝑘 ,

𝑘 = 1,2, … , 𝑚

(1)

The solution for the desired interpolating function 𝑓(𝐗) is [7] 𝑓(𝐗) =

𝑚

𝑚

𝑘=1

𝑘=1

̅̅̅̅̅̅̅ 𝐀 𝐀 ⋁ [(⋁ 𝑧𝑘 𝐗 𝑘𝐀 ) ⋁ 𝑝𝐀 ⋀(𝐗 𝑘 )] 𝐗 𝐀∈{0,1}𝑛

(2)

where 𝐀 = [𝑎1 , 𝑎2 , … , 𝑎𝑛 ]𝑇 , 𝑝𝐀 is a parameter that belongs to the underlying Boolean algebra 𝐵 and 𝐗 𝐀 is the primitive product (minterm) given by 𝑎

𝑎

𝑎

𝐗 𝐀 = 𝐗 (𝑎1 ,𝑎2,…,𝑎𝑛 ) = 𝑋1 1 𝑋2 2 … 𝑋2 𝑛

where

(3)

(4)

Equation (2) is valid subject to the consistency condition [7] 𝑚

𝑚

𝑛

⋁ ⋁ [(𝑧𝑘 ⊕ 𝑧ℎ ) ⋀(𝑋𝑘,𝑖 ⊙ 𝑋ℎ,𝑖 )] = 0 𝑘=1 ℎ=1

(5)

𝑖=1

This consistency condition is needed for a solution to exist. Equation (2) reduces to the unique solution 𝑚

𝑓(𝐗) = ⋁ (⋁ 𝑧𝑘 𝐗 𝑘𝐀 ) 𝐗 𝐀 𝐀∈{0,1}𝑛

2. On Boolean Curve Fitting

if 𝑎𝑖 = 1 if 𝑎𝑖 = 0

(6)

𝑘=1

if, and only if [3, 7] 𝑚 𝐀 ̅̅̅̅̅̅ ⋁ ⋀(𝐗 𝑘) = 0

(7)

𝐀∈{0,1}𝑛 𝑘=1

3. On the Inverse Problem of Boolean Equations The Forward Problem of Boolean equations (FPBE) is to find the solutions of a system of Boolean equations typically reduced to a single equation 𝑓(𝐗) = 0 (or 𝑔(𝐗) = 1) where 𝑓, 𝑔: 𝐵 𝑛 → 𝐵, and 𝐵 is an arbitrary Boolean algebra. By contrast, the Inverse Problem of Boolean equations (IPBE) is to construct the equation 𝑓(𝐗) = 0 (or 𝑔(𝐗) = 1) given the consistency condition for its solution 𝑠0 = 0 together with the complete set of particular solutions 𝐗 𝑘 , 𝑘 = 1,2, … , 𝑚 such that 𝑓(𝐗 𝑘 ) = 0 (or 𝑔(𝐗 𝑘 ) = 1) for 𝑘 = 1,2, … , 𝑚. Implicit in this definition is that 𝑓(𝐗) ≠ 0 (or, respectively, 𝑔(𝐗) ≠ 1) for any 𝐗 that does not belong to the set {𝐗1 , 𝐗 2 , … , 𝐗 𝑚 }. Noting that {𝑓(𝐗) = 0} is implied by {𝑠0 = 0} and {𝐗 = 𝐗 𝑘 , 𝑘 = 1,2, … , 𝑚} and nothing else, Rushdi and Albarakati [13] obtained an expression for 𝑓(𝐗) that can be rewritten in the current notation as

5

On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations

𝑚

𝑛

𝑚

⋁ ⋀ (⋁(𝑋𝑖 ⊕ 𝑋𝑘,𝑖 )) 𝐗 𝐀 ∨ 𝑠0

𝑓(𝐗) =

𝐀∈{0,1}𝑛 𝑘=1

𝐀∈{0,1}𝑛 𝑘=1 𝑚

𝑖=1

𝐀∈{0,1}𝑛 𝑘=1

𝐀∈{0,1}𝑛 𝑘=1

(9)

𝑖=1

4. The Relation between the BCF and the IPBE The problem of Boolean curve fitting is somewhat similar to the Inverse Problem of Boolean equations when z𝑘 = 0 for 𝑘 = 1,2, … , 𝑚. Under these conditions, the consistency condition (5) reduces to the trivial identity {0 = 0}, and the interpolating function (2) reduces to

𝑚

𝑛

𝑚

̅̅̅̅̅̅̅ 𝐀 𝐀 ⋁ (𝑝𝐀 ⋀(𝐗 𝑘 )) 𝐗 𝐀∈{0,1}𝑛

𝑖=1

𝑘=1

i =1

(10)

𝑚

(11)

𝑚

=

⋁ 𝐀∈{0,1}𝑛

= =

𝑖=1 𝑛

𝑖=1 𝑛

𝑖=1 𝑛

𝑘=1 𝑚

𝑖=1 𝑛

(12)

𝑖=1

⋁ 𝑝𝐀 ⋀ (⋁(𝑋𝑖 ⊕ 𝑋𝑘,𝑖 )) 𝐗 𝐀 𝐀∈{0,1}𝑛

𝑘=1

(16)

5. Illustrative Example

⋁ 𝑝𝐀 ⋀ (⋁(𝑋𝑖 ⊕ 𝑋𝑘,𝑖 )) ⋀(𝑋𝑖 ⊙ 𝑎𝑖 ) 𝐀∈{0,1}𝑛

𝑝𝐀 = 1, ∀ 𝐀 ∈ {0,1}𝑛

𝑝𝐀 ⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) ⋀(𝑋𝑖 ⊙ 𝑎𝑖 ) 𝑘=1 𝑚

(15)

Equation (16) means that a sufficient, but no necessary, condition for 𝑓BCF (𝑋) = 𝑓IPBE (𝑋) is 𝑝𝐀 = 1.

𝑛

𝑝𝐀 ⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) 𝐗 𝐀 𝑛

∀𝐀 ∈ {0,1}𝑛

𝑖=1

Conditions (14) or (15) are satisfied, in paricular, if

Therefore, the interpolating function (10) reduces to 𝑘=1

𝑛

⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) ≤ 𝑝𝐀 , 𝑘=1

𝑖=1

𝐀∈{0,1}𝑛

(14)

Or equivalently

𝑛 𝑛 ̅̅̅̅̅̅̅̅̅̅̅̅̅̅̅̅̅̅ ̅̅̅̅̅̅̅ (𝐗 𝑘𝐀 ) = ⋀(𝑎i ⊙ 𝑋𝑘,i ) = ⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )

𝑚

𝑖=1

∀ 𝐀 ∈ {0,1}𝑛

𝑘=1

The complemented primtive product in (10) can be simpified via (3) and (4) to



𝑛

𝑝𝐀 ⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) = ⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) , 𝑘=1

𝑓BCF (𝐗) =

𝑖=1

The function 𝑓(𝐗) obtained in (13) by the IPBE is exactly the same as the one obtained by the BCF in (12) except for an extra multiplicative factor 𝑝𝐀 that appears in each cell 𝐀 ∈ {0,1}𝑛 in (12). While the function 𝑓IPBE (𝐗) in (13) is unique, the function 𝑓BCF (𝐗) in (12) might have many values depending on the values of the parameters 𝑝𝐀 . One of the possible values of 𝑓BCF (𝐗) is 𝑓IPBE (𝐗), obtained under the conditions

𝑚

𝑓BCF (𝐗) =

(13)

𝑛

⋁ ⋁ (⋀(𝑋𝑖 ⊙ 𝑋𝑘,𝑖 )) 𝐗 𝐀 ∧ 𝑠̅0

𝑔(𝐗) =

𝑖=1 𝑛

= ⋁ ⋀ (⋁(𝑎𝑖 ⊕ 𝑋𝑘,𝑖 )) 𝐗 𝐀

Correspondingly, 𝑔(𝐗) is given by 𝑚

𝑛

𝑓IPBE (𝐗) = ⋁ ⋀ (⋁(𝑋𝑖 ⊕ 𝑋𝑘,𝑖 )) 𝐗 𝐀

(8)

𝑖=1

On the other hand, the inverse function recovered via (8), whenever no consistency condition is required (𝑠0 = 0) is given by

Consider the BCF problem of finding an 2 interpolating Boolean function 𝑓: 𝐵16 → 𝐵16, where 𝐵16 = FB{𝑎, 𝑏}, the free Boolean algebra with generators 𝑎 and 𝑏, such that it 3 represents a curve in the Boolean space 𝐵16 that passes through the four points. 𝑘 𝐗𝑘 𝑧𝑘

1 (𝑎𝑏̅ , 𝑎̅𝑏) 0

2 (𝑎, 𝑏) 0

3 (𝑏̅, 𝑎̅) 0

4 (𝑎 ∨ 𝑏̅, 𝑎̅ ∨ 𝑏) 0

6

Ali M. Rushdi and Ahmed S. Balamesh

It is clear from (5) that the consistency condition for this BCF problem is the trivial identity (0 = 0). Figures 1 and 2 demonstrate the evolution of the variable-entered Karnaugh map (VEKM) representation for 𝑓BCF (𝐗) expressed via (12). Thus, the final parametric solution can be read from the VEKM in Fig. 2 as [14-17] 𝑓BCF (𝑋1 , 𝑋2 ) = 𝑝0 (𝑎̅𝑏 ∨ 𝑎𝑏̅)𝑋̅1 𝑋̅2 ∨ 𝑝1 (𝑎 ∨ 𝑏̅)𝑋̅1 𝑋2 ∨ 𝑝2 (𝑎̅ ∨ 𝑏)𝑋1 𝑋̅2 ∨ 𝑝3 (𝑎𝑏̅ ∨ 𝑎̅𝑏)𝑋1 𝑋2

(18)

Figure 3 displays the VEKM representation for 𝑓IPBE (𝐗) expressed via (13). Thus, the final unique solution can be read from the VEKM in Fig. 3 as [14-17] 𝑓IPBE (𝑋1 , 𝑋2 ) = (𝑎̅𝑏 ∨ 𝑎𝑏̅)𝑋̅1 𝑋̅2 ∨ (𝑎 ∨ 𝑏̅)𝑋̅1 𝑋2 ∨ (𝑎̅ ∨ 𝑏)𝑋1 𝑋̅2 ∨ (𝑎𝑏̅ ∨ 𝑎̅𝑏)𝑋1 𝑋2

(19)

(17)

where, with a little twist of notation, we are using 𝑝0 , 𝑝1 , 𝑝2 and 𝑝3 to stand for 𝑝𝐴 ∈ 𝐴 = {0,1}2 = {00,01,10,11} or for 𝑝00 , 𝑝01 , 𝑝10 and 𝑝11. The corresponding IPBE is to find the equation 𝑓(𝐗) = 𝑓(𝑋1 , 𝑋2 ) = 0, where 2 𝑓: 𝐵16 → 𝐵16 = FB{𝑎, 𝑏} such that it has a consistency condition {0 = 0} and a set of particular solutions

𝑋2

{(𝑎𝑏̅, 𝑎̅𝑏), (𝑎, 𝑏), (𝑏̅, 𝑎̅), (𝑎 ∨ 𝑏̅, 𝑎̅ ∨ 𝑏)}

Matching the terms in (17) and (19), we can see that the solution in (19) can be obtained as a special case of that in (17) under the conditions (15), namely (𝑎̅𝑏 ∨ 𝑎𝑏̅) ≤ 𝑝0 ,

(𝑎 ∨ 𝑏̅) ≤ 𝑝1 , (𝑎̅ ∨ 𝑏) ≤ 𝑝2 , (𝑎𝑏̅ ∨ 𝑎̅𝑏) ≤ 𝑝3

𝑋1 𝑝0 (𝑎𝑏̅ ∨ 𝑎̅𝑏) 𝑝1 (𝑎̅ ∨ 𝑏 ∨ 𝑎̅𝑏) (𝑎 ∨ 𝑏) (𝑎̅ ∨ 𝑏) (𝑏 ∨ 𝑎̅) (𝑏̅ ∨ 𝑎̅) (𝑎̅𝑏 ∨ 𝑎̅ ∨ 𝑏) (𝑎 ∨ 𝑏̅ ∨ 𝑎̅ ∨ 𝑏) 𝑝2 (𝑎𝑏̅ ∨ 𝑎 ∨ 𝑏̅) 𝑝3 (𝑎̅ ∨ 𝑏 ∨ 𝑎 ∨ 𝑏̅) (𝑎 ∨ 𝑏̅) (𝑎̅ ∨ 𝑏̅) (𝑏 ∨ 𝑎) (𝑏̅ ∨ 𝑎) (𝑎 ∨ 𝑏̅ ∨ 𝑎𝑏̅) (𝑎̅𝑏 ∨ 𝑎𝑏̅) 𝑓BCF (𝐗)

Fig. 1. Initial VKEM representation of the function obtained via the BCF.

𝑋2

𝑋1 ̅ (𝑎 𝑝1 ̅ ∨ 𝑏) 𝑝0 (𝑎̅𝑏 ∨ 𝑎𝑏) 𝑝2 (𝑎 ∨ 𝑏̅) 𝑝3 (𝑎𝑏̅ ∨ 𝑎̅𝑏) 𝑓BCF (𝐗)

Fig. 2. Final VKEM representation of the function obtained via the BCF.

𝑋2

𝑋1 𝑎̅ ∨ 𝑏 𝑎̅𝑏 ∨ 𝑎𝑏̅ 𝑎 ∨ 𝑏̅ 𝑎𝑏̅ ∨ 𝑎̅𝑏 (𝐗) 𝑓IPBE

Fig. 3. VKEM representation of the function obtained via the IPBE.

(20)

On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations

𝑋2

7

𝑋1 𝐶10 𝑎̅𝑏̅ ∨ 𝐶11 𝑎̅𝑏 ∨ 𝐶13 𝑎𝑏 𝐶31 𝑎̅𝑏 ∨ 𝐶32 𝑎𝑏̅

𝐶01 𝑎̅𝑏 ∨ 𝐶02 𝑎𝑏̅ 𝐶20 𝑎̅𝑏̅ ∨ 𝐶22 𝑎𝑏̅ ∨ 𝐶23 𝑎𝑏 𝑓BCF (𝐗)

Fig. 4. VKEM representation with atomic entries of the function obtained via the BCF.

Each of the four parameters 𝑝𝑖 ∈ 𝐵16 = FB(𝑎, 𝑏), 0 ≤ 𝑖 ≤ 3, can be expanded in terms of the four atoms of 𝐵16 as [7] 𝑝𝑖 = 𝐶𝑖0 𝑎̅𝑏̅ ∨ 𝐶𝑖1 𝑎̅𝑏 ∨ 𝐶𝑖2 𝑎𝑏̅ ∨ 𝐶𝑖3 𝑎𝑏, 𝐶𝑖𝑗 ∈ {0,1}, 0 ≤ 𝑖 ≤ 3

(21)

Note that the expansions in (21) involve 4 × 4 = 16 binary coefficients. The entries of the VEKM in Fig. 2 can now be expressed as 𝑝0 (𝑎𝑏̅ ∨ 𝑎̅𝑏) = 𝐶01 𝑎̅𝑏 ∨ 𝐶02 𝑎𝑏̅ 𝑝1 (𝑎̅ ∨ 𝑏) = 𝐶10 𝑎̅𝑏̅ ∨ 𝐶11 𝑎̅𝑏 ∨ 𝐶13 𝑎𝑏 𝑝2 (𝑎 ∨ 𝑏̅) = 𝐶20 𝑎̅𝑏̅ ∨ 𝐶22 𝑎𝑏̅ ∨ 𝐶23 𝑎𝑏 𝑝3 (𝑎𝑏̅ ∨ 𝑎̅𝑏) = 𝐶31 𝑎̅𝑏 ∨ 𝐶32 𝑎𝑏̅

condition in either problem, the two problems yield solutions that differ only via an arbitrary multiplicative parameter needed in the BCF problem. The BCF problem might have conditioned or unconditioned solutions that might be numerous or unique or it might have no solutions at all. By contrast, the IPBE is guaranteed to have a unique solution that happens to be one of those produced by the BCF problem. References

(22)

We now replace the VEKM of Fig. 2 by the one of atomic entries in Fig. 4, in which 10 only of the aforementioned binary coefficients remain. Since each of these coefficients can be assigned two values independently of the others, the number of distinct particular solutions expressed by 𝑓BCF (𝐗) in (17) is 210 = 1024. This is the number of curves passing through the four points in the given Boolean space.

[1]

Stamm, E., Geometrische Theorie logischer Funktionen: Beitrag zur Algebra der Logik (Geometrical theory of logical functions: Contribution to the algebra of logic), Prace MatematycznoFizyczne, 34(1): 119-158 (1925), In German.

[2]

McKinsey, J. C. C., On Boolean functions of many variables, Transactions of the American Mathematical Society, 40(3): 343-362 (1936).

[3]

McKinsey, J. C. C., Boolean functions and points, Duke Mathematical Journal, 2(3): 465-471 (1936).

[4]

Ellis, D., Remarks on Boolean functions, Journal of the Mathematical Society of Japan, 5(3-4): 345-350 (1953).

[5]

Ellis, D. Remarks on Boolean functions II, Journal of the Mathematical Society of Japan, 8(4): 363-368 (1956).

[6]

Scognamiglio, G., Interpolazione per le funzioni algebriche booleane (Interpolation for Boolean algebraic functions), Giorn. Mat. Battaglini, 89: 14-41 (1961), In Italian.

[7]

Rudeanu, S., Boolean Functions and Equations, North-Holland Publishing Company & American Elsevier, Amsterdam, the Netherlands (1974).

[8]

Melter, R. A. and Rudeanu, S., Linear equations and interpolation in Boolean algebra, Linear Algebra and Its Applications, 57: 31-40 (1984).

[9]

Löwenheim, L., Gebietsdeterminanten (Domain determinants), Mathematische Annalen, 79(3): 223236 (1918), In German.

[10]

Rushdi, A. M. and Balamesh, A. S., Boolean Curve

5. Conclusion This paper explores the relation between the problem of Boolean curve fitting (BCF) and the problem of the Inverse Problem (IPBE) of Boolean equations. Despite the great similarity between the two problems, there is a subtle difference between them as the first might require a consistency condition for its solution while the second might use such a condition as input. Without a consistency

8

Ali M. Rushdi and Ahmed S. Balamesh

Fitting with the Aid of the Variable-Entered Karnaugh Map, forthcoming ISA. [11]

[12]

Ahmad, W. and Rushdi, A. M. A., A new cryptographic scheme utilizing the difficulty of big Boolean satisfiability, International Journal of Mathematical, Engineering and Management Sciences (IJMEMS), 3(1): 47-61 (2018). Balamesh, A. S., and Rushdi, A. M., Implementation and cryptanalysis of a novel cryptosystem based on Boolean curve fitting over a big Boolean algebra, forthcoming ISA.

[13]

Rushdi, A. M. A. and Albarakati, H. M., The inverse problem for Boolean equations, Journal of Computer Science, 8(12): 2098-2105 (2012).

[14]

Rushdi, A. M., Improved variable-entered Karnaugh map procedures, Computers and Electrical Engineering, 13(1): 41-52 (1987).

[15]

Rushdi, A. M. and Al-Yahya, H. A., A Boolean minimization procedure using the variable entered

Karnaugh map and the generalized consensus concept, International Journal of Electronics, 87(7): 769-794 (2000). [16]

Rushdi, A. M. and Al-Yahya, H. A., Further improved variable-entered Karnaugh map procedures or obtaining the irredundant forms of an incompletelyspecified switching function, Journal of King Abdulaziz University: Engineering Sciences, 13(1): 111-152 (2001).

[17]

Rushdi, A. M., and Amashah, M. H., Using variable-entered Karnaugh maps to produce compact parametric general solutions of Boolean equations, International Journal of Computer Mathematics, 88(15), 3136-3149 (2011).

‫‪9‬‬

‫‪On the Relation between Boolean Curve Fitting and the Inverse Problem of Boolean Equations‬‬

‫حول العالقة بين مواءمة المنحنيات البوالنية والمسألة العكسية للمعادالت البوالنية‬ ‫علي محمد رشدي و أحمد سعيد بالعمش‬ ‫قسم الهندسة الكهربائية وهندسة الحاسبات‪ ،‬كلية الهندسة‪ ،‬جامعة الملك عبدالعزيز‪ ،‬ص‪.‬ب ‪ ،.80204‬جدة ‪ ،21589‬المملكة‬ ‫العربية السعودية‬

‫‪[email protected]‬‬ ‫المستخلص‪ .‬تستكشف ورقة البحث هذه التشابهات واالختالفات بين مسألتين بارزتين في‬ ‫رياضيات الدوال البوالنية‪ .‬أولى هاتين المسألتين هي مسألة مواءمة المنحنيات البوالنية (و ن‬ ‫ب)‪ ،‬التي تعرف أيضا باسم مسألة االستكمال البوالني‪ ،‬وهي تتعلق برسم المنحنى )𝑿(𝑓 = 𝑧‬

‫بحيث يمر خالل النقاط ) 𝑘 𝐗(𝑓 = 𝑘‪ z‬حيث 𝑚 ‪ .𝑘 = 1,2, … ,‬أما المسألة الثانية فهي‬ ‫المسألة العكسية (س ع) للمعادالت البوالنية التي توجد دالة بوالنية )𝑿(𝑓 معلوم جميع‬ ‫أصفارها‪ .‬وبينما قد تحتاج مسألة مواءمة المنحنيات البوالنية شرطا لالتساق ليتم حلها‪ ،‬فإن‬ ‫المسألة العكسية للمعادالت البوالنية ربما تستخدم شرط اتساق كمدخل لها‪ .‬وفي حالة انعدام‬

‫شرط االتساق تمثل المسألة العكسية للمعادالت البوالنية حالة خاصة من مسألة مواءمة‬ ‫المنحنيات البوالنية‪ ،‬شريطة أن تكون قيم النقاط المحددة 𝑘‪ z‬جميعها ووحدها مساوية للصفر‪ .‬يتم‬ ‫توضيح نتائجنا من خالل مثال تفصيلي نمطي‪.‬‬ ‫كلمات مفتاحية‪ :‬مواءمة المنحنيات البوالنية‪ ،‬المسألة العكسية‪ ،‬المعادالت البوالنية‪ ،‬شرط‬ ‫االتساق‪ ،‬التفرد‪ ،‬الحلول الخاصة‪.‬‬

10

Ali M. Rushdi and Ahmed S. Balamesh

Chemical and Material Engineering

JKAU: Eng. Sci., Vol. 28 No. 2, pp: 13 – 23 (1438 A.H./ 2017 A.D.) Doi: 10.4197/Eng. 28-2.2

Development of Tribological Performance for Epoxy Composites A. M. M. Al Owad and A. M. Samy Faculty of Engineering, Jazan University, Jazan, Saudi Arabia Abstract. The environment of Arab countries suffers from the relatively high concentration of dust in air, due to the lack of rain and the vast area of desert, which reason increase in wear value of sliding parts. To overcome those severe environmental impacts, it is necessary to develop the materials which can resist the abrasion action of sand. Epoxy composites, like polymers, suffer from the relatively low wear resistance. The present research aims to develop epoxy composites to be used as bearing material in different engineering applications. To enable epoxy resin to be used as bearing material, it is proposed to use solid lubricant, such as molybdenum disulfide and Talc powders as filling material. Test specimens in a form of a layer of 50 × 50 mm 2, with 3 mm thickness adhered into a wooden block. The tested materials were epoxy filled by different contents of molybdenum disulfide and Talc powders 1, 2, 3, 4 and 5 %. The Friction experimental was carried out at different values of normal load 2, 4, 6 and 8 N. Test results show that, in presence of 2 N normal loads, the maximum value of friction coefficient was (0.41) observed at pure epoxy specimens. While minimum values of friction coefficient observed at epoxy specimens contain 5 % Mos2 was (0.1). This results related to strong bonding between Mos2 and epoxy resin. The friction coefficient can be decrease for epoxy composite by increasing molybdenum disulfide content. This behavior related to the good lubricant properties of molybdenum disulfide. The wear resistance can be increase for epoxy composite by increasing molybdenum disulfide content up to 5%. The molybdenum disulfide helps specimens to sliding to counter face and decrease bonding between epoxy and steel surface. The talc show significant reduction of friction coefficient in presence of higher load. The effect of talc on wear resistance was insignificant because non-homogeneous of talc with epoxy resin. Keywords: Wear resistance, Friction coefficient, Epoxy, Molybdenum disulfide, Talc and scratch test.

investigate experimentally [3, 4], due to the possible synergism with other influences, so that it’s necessary to development the materials. Lubrication is important for reduce wear and friction for moving parts in mechanical systems [5], that operate for extended time periods. Developing engineering materials and lubricants that can be used in mechanical systems without replenishment- especially, those that are environmentally friendly is very important for increasing wear resistance and the functional useful life of mechanical components.

1. Introduction In dusty environment, abrasive particles such as sand entering in the machines cause serious wear of the moving parts in machines, [1, 2]. Abrasive wear of engineering materials is a complicated surface failure, useful life and damage process, affected by a number of factors, such as lubrication and tribological properties of the material and the abrasive, environmental impact, … etc. Microstructure is one of the important factors; however, its effect on the wear mechanism is difficult to

13

14

A. M. M. Al Owad and A. M. Samy

The increasing demand of using epoxy composites in engineering applications requires extensive researches to develop their thermal, tribological and mechanical properties. One of the common and widely used methods to improve the tribological properties is to incorporate solid lubricants and metallic filling materials into epoxy matrix [6 10] . Epoxy coatings of tillage tools were reinforced by metallic mesh as well as wool, polyamide, cotton and acrylonitrile textiles [11]. Abrasive wear of moving surfaces generated by sand particles represents a major problem, and there is an increasing demand to develop materials of high wear resistance to save power and reduce wear losses in different system and engineering applications. The aim of abrasive wear of polymer matrix composites has received attention over the past four decades. The increased interest in this area aims to use polymeric composites in different application, such as aerospace, transportation and process industries, in which they can be subjected to multiple solid or liquid particle impact [12 - 15] where durability is a prime consideration. Typical examples of dusty environments, where polymer composites are applied are belt conveyors and pipelines carrying sand, slurries in petroleum refining, mechanical machines, high speed vehicles and turbines, and aircraft engine blades. Differences in the wear behavior of various types of polymeric matrix composites are caused by the content, type and properties of the reinforcement on the one hand and by the type and properties of the matrix and its adhesion to the fibers or fillers on the other. In desert areas, abrasive particles, such as sand entering the machines, cause increase in wear of the sliding components. To improve the wear resistance of the moving parts, the aluminum oxide, and carbon nano-particle strengthened nickel-based brush plating composite coatings were prepared by co-

deposition of particles with Nickel metal– matrix [16]. The main wear behavior of the composite material under abrasive contaminant lubrication is plastic deformation, failure and scuffing wear. The superior wear resistance of the composite materials is related to its fine compact microstructures and high micro-hardness. It is well known that the failure of engines is mainly caused by wear of machine elements. The classification of the operating conditions and the useful life of tribo-components without stopping a system can improve the safety and reliability of the engine. The classification is carried out by the physical inspection and the chemical examination of wear debris to monitor the lubricating condition and to foretell failure [17 – 19]. A classification technique that can observed quantitatively wear value under lubricated condition was developed using on-line particle counter [20]. The wear amounts acquired by the quantitative estimation were fairly similar to the measured values of mass loss of the specimen. The present work aims to develop epoxy composites to be used as bearing material in different engineering applications. To enable epoxy resin to be used as bearing material, it is proposed to use solid lubricant, such as molybdenum disulfide and talc powders as filling material. 2. Experimental Work Scratch tester shown in Fig. 1 was used in the experiments. It consists of a rigid stylus mount, a diamond stylus of apex angle 90° and hemispherical tip. The stylus was mounted to the tool holder through three jaw chuck. A dead weight was used to balance the loading lever before test. Normal load was applied by weights of 2, 4, 6 and 8 N. Scratch resistance force was measured using load cell mounted to the loading lever and connected to display digital monitor. The test specimen was held in

15

Development of Tribological Performance for Epoxy Composites

the vice mounted in a horizontal base with a manual driving mechanism to move specimen in a straight direction. The test specimens were scratched by an indenter. The scratch force was measured during the test, and then friction coefficient was calculated. Test specimens in a form of a layer of 50 × 50 mm2 molded on wooden block. The tested materials were epoxy filled by different contents of molybdenum disulfide and talc 1, 2, 3, 4 and 5 %. The Friction test was carried out at different values of normal load 2, 4, 6 and 8 N. Wear resistance can be obtained by measure wear scar width. The friction force measure from load cell and the normal load measure by dead weight . The test specimens are shown in Fig. 2. Where the epoxy resin mixed with hardener by

Balance Wight

Load cell

percentage 1:1, then mixed epoxy by different content from molybdenum disulfide and talc. This mixture was pouring on wooden block by thickness 3 mm. Figure 3 shows the arrangement of scratch tool and test specimens, where the scratch tool fixed in tool holder and test specimens in the vice. For carried the test applied on tool holder by dead load the move the test specimens in the direction of tool cased wear scar. The details of scratch tool and specimen are shown in Fig. 4. Wear scar width measured by Auto CAD program. And friction coefficient calculated by dividing friction force on normal load. The scar width is the guide for indicate the value of wear resistance for test specimens.

Normal Load

Tool Holder

Digital Screen

Fig. 1. Arrangement of friction tester.

16

A. M. M. Al Owad and A. M. Samy

Fig. 2. Epoxy test specimens.

Fig. 3. Arrangement of scratch tool and specimens.

Fig. 4. Details of scratch tool and specimens.

3. Results and Discussion 3. 1. Results of Friction Test for Epoxy Composite Figure 5 shows the relation between friction coefficient and solid lubricant content,

for epoxy composite at 2 N normal load. It can be noticed that the friction coefficient decrease with increasing molybdenum disulfide (Mos2) content up to 5 % Mos2 content. In presences of Talc the friction coefficient increase with

Development of Tribological Performance for Epoxy Composites

17

increasing talc content up to 2% then decrease with increasing talc. This behavior related to more homogeneous between epoxy and talc. The minimum friction coefficient was 0.09 observed at 5 % Mos2 content.

and talc for 4 and 5% show increase in wear, this behavior may be related to weakness of bonding between solid lubricant and epoxy. The lower value of wear scar width observed at specimens contain 3 % Mos2.

Friction coefficient of epoxy composite filling by solid lubricant at 4 N normal loads is shown in Fig. 6. Friction coefficient increases with increasing talc content up to 3 %, then decrease for 4 and 5 % when adding talc to epoxy. The Mos2 has more significant in reduction friction coefficient for epoxy composites. Friction coefficient decreased with increasing Mos2 contents. Minimum values of friction coefficient were observed for 5 % Mos2 content.

Figure 10 shows the relation between wear scar width and solid lubricant content, for epoxy test specimens filled by Mos2 and talc. It can be noticed that increase wear resistance for epoxy specimens contains 4 % Mos2. Adding talc to epoxy shows insignificant effect on wear resistance. The minimum value of wear scar width observed at 4 % Mos2.

Friction coefficient of epoxy test specimens filled by Mos2 and talc is shown in Fig. 7. Friction coefficient decreased with increasing Mos2 and talc content up to 4 %. This behavior confirms that the bonding between epoxy and Mos2 and talc particles is very strong. Minimum values of friction coefficient were observed for contain 4 % talc. Increasing Mos2 and Talc up to 5 % was insignificant effect. Figure 8 shows the relation between friction coefficient and solid lubricant content, for epoxy test specimens at 8 N normal loads. It can be noticed that the friction coefficient decrease with increasing Mos2 content up to 2%. Then friction coefficient increase with increasing Mos2 and content. Adding talc to epoxy showed the same behavior for Mos2. The minimum value of friction coefficient displayed by epoxy composite containing 2 % Mos2. 3- 2. Results of Friction Test for Epoxy Composite Wear of epoxy test specimens versus solid lubricant content is shown in Fig. 9. Increase Mos2 and talc content up to 3% show significant decreasing in wear values. This behavior may be related to the scratch tool is slid on surface of specimens. Increase Mos2

Figure 11 shows the relation between wear scar width and solid lubricant content, for epoxy test specimens filled by Mos2 and talc. It can be noticed that the wear resistance increases with increasing Mos2 content. This behavior may be related to more homogenous between epoxy and Mos2. The homogeny decreased in presence of talc with increasing content more than 3 %. The minimum wear observed at specimens of epoxy contains 5 % Mos2. Figure 12 shows the relation between wear scar width and solid lubricant content, for epoxy test specimens filled by Mos2 and talc. It can be noticed that the same behavior for Fig. 11. This behavior closed on the fact of Mos2 is more homogeneous with epoxy compared to talc. The minimum value of wear scar width was 0.21 mm observed at specimens contain 5% Mos2. 5. Conclusions 1. In presence of 2 N normal loads, the maximum value of friction coefficient was (0.41) observed at pure epoxy specimens. While minimum values of friction coefficient observed at epoxy specimens contain 5 % Mos2 was (0.1). These results related to strong bonding between Mos2 and epoxy resin. 2. The friction coefficient can be decrease for epoxy composite by increasing

18

A. M. M. Al Owad and A. M. Samy

molybdenum disulfide content. This behavior related to the good lubricant properties of molybdenum disulfide. 3. The wear resistance can be increase for epoxy composite by increasing molybdenum disulfide content up to 5%. The molybdenum disulfide helps specimens to

sliding to counter face and decrease bonding between epoxy and steel surface. 4. The talc show significant reduction of friction coefficient in presence of higher load. The effect of talc on wear resistance was insignificant because non-homogeneous of talc with epoxy resin.

Fig. 5. Friction coefficient of epoxy test specimens filled by Mos2 and talc powder at normal load, 2 N.

Fig. 6. Friction coefficient of epoxy test specimenst filled by Mos2 and talc powder at normal load, 4 N.

Development of Tribological Performance for Epoxy Composites

Fig. 7. Friction coefficient of epoxy test specimenst filled by Mos2 and talc powder at normal load, 6 N.

Fig. 8. Friction coefficient of epoxy test specimenst filled by Mos2 and talc powder at normal load, 8 N.

19

20

A. M. M. Al Owad and A. M. Samy

Fig. 9. Wear of epoxy test specimens filled by Mos2 and talc powder at normal load, 2 N.

Fig. 10. Wear of epoxy test specimenst filled by Mos2 and talc powder at normal load, 4 N.

Development of Tribological Performance for Epoxy Composites

Fig. 11. Wear of epoxy test specimens filled by Mos2 and talc powder at normal load, 6 N.

Fig. 12. Wear of epoxy test specimens filled by Mos2 and talc powder at normal load, 8 N.

21

22

A. M. M. Al Owad and A. M. Samy

References

Science and Engineering A, 360(1 – 2) 15 November: 46 – 57 (2003).

[1] Lingzhong, D., Binshi, X., Shiyun, D., Hua, Y. and Weiyi, T., "Study of tribological characteristics and wear mechanism of nano-particle strengthened nickelbased composite coatings under abrasive contaminant lubrication", Wear, 257: 1058 – 1063 (2004).

[11] Ali, W. Y., “Friction and Wear of Epoxy Filled by Oil and Reinforced by Woven Polyethylene, Polyester and Glass Fibre Sheets”, Journal of the Egyptian Society of Tribology, 2(3) October: 48 – 57 (2004).

[2] Harsha, A. P., Tewari, U. S. and Venkatraman, B., "Three-body abrasive wear behaviour of polyaryletherketone composites", Wear, 254: 680-692 (2003).

[12] Patnaik, A., Satapathy, A., Chand, N., Barkoula, N. M. and Biswas, S., "Solid particle erosion wear characteristics of fiber and particulate filled polymer composites: A review", Wear, 268: 249 – 263 (2010).

[3]

[13] Ivosevic, M., Knight, R., Kalidindi, S. R., Palmese, G. R. and Sutter, J. K., “Solid particle erosion resistance of thermally sprayed functionally graded coatings for polymer matrix composites”, Surface and Coating Technology, 200: 5145 – 5151 (2006).

Hu, J., Li D.Y. and Llewellyn, R., "Computational investigation of microstructural effects on abrasive wear of composite materials ", Wear, 259: 6-17 (2005).

[4] Yousif, B. F. and El-Tayeb, N.S.M., " Wear characteristics of thermoset composite under high stress three-body abrasive", Tribology International, 43: 23562371 (2010). [5] Pushkarraj, D., Michael, L., Sawyer, G. and Mobley, A., "On the friction and wear performance of boric acid lubricant combinations in extended duration operations", Wear, 260: 1295-1304 (2006). [6]

Khattab, A. A., Mahmoud, M. M. and Ali, W. Y., “Tribological Behaviour of Epoxy Composites Filled by Solid Lubricants and Oil”, 8th International Conference on Tribology, June 2004, Veszprém, Hungary (2004).

[7] Mansour, H., Ezzat, F. H. and Ali, W., “Effect of Molybdenum Disulphide as Solid Lubricant on Friction and Wear of Epoxy Based Tin Composites”, Proceedings of the 6th International Conference of Tribology, EGTRIB6, December 28 - 29, 2002, Faculty of Engineering, Cairo University, pp: 303 – 314 (2002). [8] Mansour, H., Ezzat, F. H. and Ali, W., “Effect of Graphite as Solid Lubricant on Friction and Wear of Epoxy Based Tin Composites”, Proceedings of the 6th International Conference of Tribology, EGTRIB 6, December 28 - 29, 2002, Faculty of Engineering, Cairo University, pp: 293 – 302 (2002). [9] Xua, J., Zhu, M. H., Zhou, Z. R., Kapsa, Ph. and Vincent, L., “An Investigation on Fretting Wear Life of Bonded MoS2 Solid Lubricant Coatings in Complex Conditions”, Wear, 255 (1 – 6), August - September: 253 – 258, 14th International Conference on Wear of Materials (2003). [10] Bloom, P. D., Baikerikar, K. G., Anderegg, J. W. and Valerie, V., “Fabrication And Wear Resistance of Al Cu Fe Quasicrystal-Epoxy Composite Materials”, Materials

[14] Sutter, J. K., Miyoshi, K., Bowman, C. Naik,, S. K., Ma, K., Sinatra, R., Cupp, R. Horan, R. and Leissler, G, “Erosion coatings for polymer matrix composites in propulsion Applications”, High Performance Polymers, 15 (4): 421 – 440 (2003). [15] Dalili, N., Edrisy, A. and Carriveau, R. “A review of surface engineering issues critical to wind turbine performance”, Renewable and Sustainable Energy Reviews 13 (2):428 – 438 (2009). [16] Du, L., Xu, B., Dong, S., Yang, H. and Tu, W., “Study of tribological characteristics and wear mechanism of nano-particle strengthened nickel-based composite coatings under abrasive contaminant lubrication”, Wear 257:1058 – 1063, (2004). [17] Lee, G. Y., Dharan, C. K. H. and Ritchie, R. O., "A Physically-Based Abrasive Wear Model for Composite Materials , Wear, 252: 322 – 331 (2002). [18] Raadnui, S., “Wear particle analysis - Utilization of Quantitative Computer Image Analysis: A Review”, Tribology International, 38: 871 – 878 (2005). [19] Stachowiak, G. W. and Podsiadlo, P., “Towards the Development of an Automated Wear Particle Classification System”, Tribology International, 39: 1615 – 1623 (2006). [20] Iwai, Y., Honda, T., Miyajima, T., Yoshinaga S., Higashi M. and Fuwa Y., “Quantitative estimation of wear amounts by real time measurement of wear debris in lubricating oil”, Tribology International, 43: 388 394 (2010).

‫‪23‬‬

‫‪Development of Tribological Performance for Epoxy Composites‬‬

‫تطوير األداء الترايبولوجي لمؤلفات اإليبوكسي‬ ‫علي محمد مداوي آل عوض و عبدالحليم محمود سامي‬ ‫كلية الهندسة – جامعة جازان ‪ ،‬المملكة العربية السعودية‬ ‫المستخلص‪ .‬تعاني الدول العربية من اتساع المناطق الصحراوية‪ ،‬مما يؤدي إلي زيادة نسبة‬ ‫الغبار والرمال العالقة بالهواء‪ .‬وتؤدي الرمال إلي زيادة معدالت التآكل لألسطح الدورانية في‬ ‫المعدات الميكانيكية‪ .‬وللتغلب علي هذا األثر البيئي كان من الضروري تطوير المواد لزيادة‬

‫مقاومتها للتآكل الحادث من الرمال‪ ،‬وحيث إن مادة اإليبوكسي الشائعة االستخدام في تطبيقات‬ ‫كراسي المحاور االنزالقية تعاني من انخفاض مقامتها للتآكل‪ .‬يهدف هذا البحث إلي تطوير‬ ‫مركبات اإليبوكسي إلمكانية استخدامها في مختلف التطبيقات‪ .‬وإلمكانية استخدام مادة‬ ‫اإليبوكسي كمواد لكراسي المحاور االنزالقية‪ ،‬تم استخدام المزلقات الصلبة مثل كبريتيد‬ ‫الموليبيدين والتلك كمواد مالئة لإليبوكسي بغرض خفض االحتكاك لتقليل الطاقة وتقليل التآكل‬

‫لزيادة عمر المعدة‪ .‬تم إجراء االختبارات علي جهاز اختبار الخدش‪ ،‬حيث أجريت االختبارات‬ ‫علي طبقات من مادة اإليبوكسي ذات أبعاد ‪ 50 × 50‬مم وسمك ‪ 3‬مم‪ .‬تمت إضافة كبريتيد‬ ‫الموليبيدين والتلك إلي اإليبوكسي بنسب تركيز ‪ 4 ،3 ،2 ،1‬و ‪ .٪ 5‬تم إجراء اختبار االحتكاك‬ ‫عند أحمال عمودية مختلفة ‪ 6 ،4 ،2‬و ‪ 8‬نيوتن‪ .‬أوضحت نتائج االختبارات أن اإليبوكسي‬ ‫الخالي من المزلقات الصلبة يعطي معامل احتكاك مرتفع يصل إلى ‪ ،0.41‬بينما في حالة‬

‫إضافة كبريتيد الموليبيدين إلى اإليبوكسي بنسبة تركيز ‪ ٪ 5‬ينخفض معامل االحتكاك إلي ‪.0.1‬‬ ‫كذلك مقاومة التآكل لإليبوكسي تزداد بزيادة نسبة كبريتيد الموليبيدين إلى ‪ .٪ 5‬إضافة التلك إلي‬ ‫اإليبوكسي يخفض االحتكاك في حالة األحمال المرتفعة‪ .‬تأثير إضافة التلك على مقاومة التآكل‬

‫ضئيل نظ اًر النخفاض التجانس بين مادة اإليبوكسي والتلك‪.‬‬ ‫يكون‬ ‫ً‬

‫كلمات مفتاحية‪ :‬مواءمة المنحنيات البوالنية‪ ،‬المسألة العكسية‪ ،‬المعادالت البوالنية‪ ،‬شرط‬ ‫االتساق‪ ،‬التفرد‪ ،‬الحلول الخاصة‪.‬‬

24

A. M. M. Al Owad and A. M. Samy

Industrial Engineering

JKAU: Eng. Sci., Vol. 28 No. 2, pp: 27 – 37 (1438 A.H./ 2017 A.D.) Doi: 10.4197/Eng. 28-2.3

The Importance of Social Media in Education and Prioritizing Process Alaa Kutbi1 and Madani Alomar2 1

Faculty of Education, University of Windsor, Windsor, Canada and 2Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia [email protected] Abstract. Social media plays a significant role because most schools take advantage of modern technologies. However, the real challenge facing instructors is the selection of the right tool to improve the effectiveness and efficiency of educational outputs. Many factors affect the selection of social media in education. Some of them are related to the ability of instructors and students to deal with different kinds of social media. The authors of this study intend to reduce the challenges that face instructors regarding the selection of the correct social media tools for educational purposes. The authors explore the judgments of a university instructor about choosing the right tool for a particular class by introducing a model that helps increase outputs. A model was constructed using multi-criteria decision analysis (MCDA) following a systematic approach to decomposing and comparing alternatives. The judgments of that instructor resulted in the selection of YouTube, Google Plus, and Twitter. Keywords: Social media, E-learning, Multi-criteria decision making and analysis, Improving educational outputs.

between internet users and maximizes the user’s part in the enrichment of digital content on the internet and the cooperation between the various users of the internet to build visual communities [3]. Paul Grabowicz believes that “Web 2.0 means moving away from using the internet to draw a passive audience to a static publishing platform, and instead embracing the broader network, where communication, collaboration, interaction and user-created content are paramount” [4]. Again, the rise of Web 2.0, or social media, has facilitated the communication and interaction between internet users and transformed the users from passive receivers to active learners.

1. Introduction Scholars believe that the emersion of Web 2.0 facilitates communication between individuals in the structure of a virtual community [1]. Dr. Mohammed Khalf-Allah, an assistant professor in educational technology, defines social media as technological applications based on Web 2.0 [2]. The goal of these applications is to achieve communication and interaction between different individuals who live around the world. As a result of this interaction and cooperation, the members of these groups can receive the maximum number of benefits from this visual community [2]. Taking this further, Web 2.0 is a tool that provides second-generation internet services. This technology supports communication

This paper discusses the advantages of social media when it is used as a teaching tool.

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Alaa Kutbi1 and Madani Alomar

The paper begins with previous studies on elearning and the usage of social media in teaching. The paper also presents a methodology and a model that helps instructors in selecting the right tool. Finally, the paper discusses the results, limitations and future works. 2. e-learning Some people argue that using social media as a form of e-learning can help improve the outcomes of the education system. Wegerif finds that “individual success or failure on the course depended upon the extent to which students were able to cross a threshold from feeling like outsiders to feeling like insiders.” [5]. In his study, Wegerif gives an example of a student who found the elearning method to be more difficult than the face-to-face meetings because she could not cross this threshold and found the e-learning experience cold and unfriendly [5]. However, most of the students in Wegerif’s study enjoyed using social media in their education. At the end of the course, students were asked: “What did you like most about the course?” Students responses included statements that e-learning was “particularly good at supporting collaborative learning” [5]. Moreover, Väljataga and Fiedler agree with Wagerif’s study. They believe that e-learning is an “essential aspect of today’s postmodern, technologically rich society which is to develop the ability to take control and responsibility for our own education, learning, and change” [6]. 2.1 Self-Directed Learning Hayes claims that, to control our lives, people need to take control of their education [7] . In other words, “the self-directing intentional learning that can be achieved through social media is necessary for acquiring knowledge and remembering it” [3]. In their study about supporting students to self-direct

intentional learning projects with social media, Väljataga and Fiedler state that all their participating students declared that “they had a positive experience regarding the acquisition of useful theoretical knowledge and practical skills in respect to the use of social media tools and services and self-directing their own learning projects within formal educational settings and beyond” [6]. They say that the students’ reports show that they gained considerable knowledge and skills regarding the use of social media to support a range of activities. Väljataga and Fiedler conclude that students acquired some expertise regarding the meaningful combination and the selection of a diverse set of social media for their own purposes [6]. Therefore, it can be said that, by using social media as a learning technique, students will have the feeling that they have earned their knowledge, and that will make them never forget the knowledge they have acquired [3]. In addition to all the excitement and selfacquisition features that can be found in social media as a learning tool, e-learning is considered to be a student-friendly [3] environment . Following this further, social media, or e-learning in general, is a very convenient tool. It allows students to think and take their time before posting and participating. Moreover, social media is an educational tool that provides students with the opportunity to participate whenever it is convenient for them. As a matter of fact, in a study of Saudi students’ perceptions of the use of social media as a learning tool, some students stated that e-learning is better than traditional faceto-face classes [3]. They said that, in a face-to-face class, there is pressure to think fast and share answers or comments with their peers. With e-

The Importance of Social Media in Education and Prioritizing Process

learning, on the contrary, students can take as much time as they need before responding and sharing without worrying about waiting for their turn or being interrupted by others because this technology supports an egalitarian style of communication in which everyone can easily participate [3]. 2.2 Instructors and e-Learning In its various platforms, social media takes into account students’ individual differences. Different platforms offer multiple ways to participate that suit most students. Moreover, the fact that teachers ask their students to use multiple mediums (like Twitter, Facebook, and YouTube) in their learning could have a positive impact on the students’ learning processes. According to Edward Spooner, “multimedia learning seeks to give instructors the ability to stimulate both the visual and auditory channels of the learner, resulting in better progress” [8]. Taking this further, according to the dual encoding theory, Ruth Clark believes that the combination of text and graphics in educational content can affect student’s long-term memory and, thus, the learning process in general [9]. Many studies show that the integration of social media tools has a positive impact on teaching and learning by allowing teachers to involve learners by creating knowledge, sharing actively, and collaborating in the learning process [10]. Moran, Seaman, and Tinti-Kane investigate how today’s higher education faculty use social media for teaching, learning, and sharing. According to them, social media sites can be valuable tools for collaborative learning. Their results show that online videos from sites like YouTube are valuable tools for teaching [11]. Moreover, Ishtaiwa and Dukmak investigate pre-service teachers’ perceptions toward using blog and wiki applications to

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enhance their learning. They also examine preservice teachers’ perceptions toward the application that is most effective in their learning. Qualitative data collected from 15 pre-service teachers using semi-structured interviews reveals that web applications, such as blogs and wikis, are useful tools with which to facilitate collaborative learning instead of the competitive learning that dominates traditional classes. The participants regarded web applications as effective tools with which to enhance interaction, facilitate the creation, sharing, and dissemination of knowledge, as well as develop reflective and critical thinking skills [12]. Yakin and Gencel explore the utilization of social media tools for informal learning activities. They find that Facebook is an important social media tool with which to fulfill their learning activities that is preferred most students. They indicate that networking, mentoring, learning from experts, information distribution, and self-analysis activities are managed through Facebook [13]. The world of the internet or the worldwide web (www) involves many websites that provide different kinds of social media. Table 1 shows the most used social media platforms within different contexts and for various purposes [14]. However, selecting the best tool can be a real challenge for both instructors and students. The selection of the right tool depends on multiple factors that relate to subject and content, student and instructor abilities, and the overall preparations and capabilities. Therefore, the authors of this study construct a systematic model that allows instructors (sometimes with the help of students) to choose the best tool or tools with which to improve educational outputs and increase the efficiency and effectiveness of classes and educational institutions. In the next section, the

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Alaa Kutbi1 and Madani Alomar

authors propose a methodology and a model that can be used to overcome this selection problem. Table 1: Types of social media.

Social networking

Facebook LinkedIn Google Plus WordPress

Blogging

Video Sharing

Blogger Live Journal YouTube Vimeo Periscope

Live Streaming Blab Microblogging

Twitter Tumblr Digg

Social News

Reddit

3. Methodlogy The necessity of conducting multidimensional decision analysis implies the need to solve a multi-criteria decision-making (MCDM) and Multi-criteria decision analysis (MCDA) problems. MCDM or MCDA helps with the organization and simplification of multi-criteria decision problems into a systematic structure, which allows decisionmakers to visualize problems in an understandable structure. An MCDA is a subdiscipline of operations research that considers multiple levels, clusters, and criteria in decision-making situations. 3.1 The Analytical Hierarchy Process (AHP) Several MCDA techniques are available, such as value engineering (VE), the analytical hierarchy process (AHP), multi-attribute utility theory (MAUT), and the Analytical Network Process (ANP). Such techniques provide effective approaches that allow for the quantification of decisions and prioritization of factors and elements that are crucial to the

analysis, control, and improvement of performance. According to Saaty, the AHP approach assists in the following: 1. Structuring a problem as a hierarchy or system 2. Eliciting judgments that reflect subjective decisions 3. Representing those judgments with meaningful numbers 4. Using these numbers to calculate the priorities of the elements of the system or hierarchy 5. Synthesizing these results to determine overall outcomes 6. Analyzing the sensitivity to changes in judgment Saaty introduced the AHP in 1971. It has become one of the most broadly used methods of MCDM [15]. It is a decision approach that was designed to aid in the solution of complex multiple criteria problems in a number of application areas. AHP is a problem-solving framework and flexible, systematic method that is employed to represent the elements of a complex problem hierarchically [16]. It is known as an essential tool that is used to conduct research about making business decisions and examining management theories by both practicing managers and academic researchers [17]. One of the major strengths of the AHP is the use of pairwise comparisons to derive accurate ratio-scale priorities, as opposed to using the traditional approach of assigning weights, which can be difficult to justify. The procedure of solving a complex problem using the AHP involves the steps in Fig. 1. 3.2 Problem Decomposition Decomposing the complexity of a problem into levels or components and synthesizing the relations among the components are the underlying concepts of the

The Importance of Social Media in Education and Prioritizing Process

AHP. Level One involves the goal cluster and the selection of the right social media platform. The second level includes the six categories of social media: Blogging, video sharing, live streaming, microblogging, social news, and social networking. The third level includes nodes for each cluster (i.e., blogging with WordPress, Blogger, and Live Journal). Figure 2 shows the construction of the model with all clusters and nodes. 3.3 Pairwise Comparison Pairwise comparison aims to determine the relative importance of the elements at each level of the hierarchy. It starts from the second level and ends at the bottom level.

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A set of comparison matrices of all elements in a level of the hierarchy, with respect to an element at the immediately higher level, are constructed to prioritize and convert individual comparative judgments into ratio-scale measurements. The preferences are quantified using a nine-point scale. The meaning of each scale measurement is explained in Table 2. The decision-maker needs to express a preference between each pair of elements regarding how much more important one element is than another element. This means that, for each and every level in the hierarchy, a pairwise comparison matrix is required to expresses individual and subjective judgments and preferences about all elements in the level with respect to the upper-level criteria.

Fig. 1. Analytical Hierarchy Process and steps.

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Alaa Kutbi1 and Madani Alomar

Fig. 2. Clusters and nodes structure. Table 2. Pairwise ranking and scale[15]. Intensity of importance 1

Definition

Explanation

Equal Importance

The two activities/factors contribute equally to the objective. Experience and judgment slightly favor one over the other. Experience and judgment strongly favor one over the other. Experience and judgment very strongly favor one over the other. Its importance is demonstrated in practice. The evidence favouring one over the other is of the highest possible validity. When compromise is needed When activity i has one of the above numbers assigned to it with activity j, j has the reciprocal value when compared to i.

3

Somewhat More Important

5

Strong Importance

7

Very Strong Importance

9

Absolutely More/Extremely Important

2, 4, 6, 8 Reciprocal

Intermediate Values Opposite Value

According to Saaty, the relative ratio scale derived from a pairwise comparison’s reciprocal matrix of judgments is derived by solving the following equation:

,

is equal to

the trace of the matrix which consists of unit entries or the average of computed values .where aji = 1/aij or aij aji = 1 (the reciprocal property), aij >0 Thus, a is known as a positive matrix whose solution, which is known as the principal right eigenvector, is normalized using the following equation: . However, a relative ratio scale does not require a unit of measurement. When aij ajk = aik, Matrix A is said to be consistent, and its principal eigenvalue is equal to n. The general eigenvalue formulation given above is obtained by perturbation of the following consistent formulation [15]:

(1)

After the hierarchy of the problem is constructed, the matrices of pair-wise comparisons are obtained using the nine-point comparison scale in Table 2, see equation 1. In this matrix, the element aij=1/aij and thus, when i=j, aij=1. The value of wi may vary from 1 to 9, and 1/1 indicates equal importance while 9/1 indicates extreme or absolute importance. In this regard, the decision-maker has to decide on the importance of each

33

The Importance of Social Media in Education and Prioritizing Process

element over the others. For instance, with respect to the overall, which item (N1orN2) is more important/likely/preferable than the other (see Table 3). Each cell in the table refers to the personal judgment (i.e. N2 is extremely more important than N1). Table 3. Pairwise comparison within N number of elements. N1 1 … … … …

N1 N2 N3 N4 NI

N2 … 1 … … …

N3 … … 1 … …

N4 … … … 1 …

NI … … … 1

After the pairwise comparison matrix is developed, a vector of priorities (i.e. eigenvector) in the matrix is calculated and is then normalized to sum to 1.0, or 100 percent. This is done by dividing the elements of each column of the matrix by the sum of that column (i.e. normalizing the column). Then, the eigenvector is obtained by adding the elements in each resulting row to obtain a row sum and dividing this sum by the number of elements in the row to obtain a relative weight. Additionally, a consistency ratio (CR) is used to measure the consistency in the pairwise comparison. The purpose is to ensure that the judgments of decision-makers are consistent. Inconsistency may arise when max deviates from n due to inconsistent responses in pair-wise comparisons. Therefore, the matrix A should be tested for consistency using index “CI” where CI = (λ max-n). To obtain consistency ratio of matrix A, CR= CI/RI, where RI is the consistency index of a randomly generated pairwise comparison matrix. The value of RI depends on the number of items being compared as in Table 4. Table 4: Values of RI and n number of compared items [18].

n RI

3 0.58

4 0.90

5 1.12

6 1.24

7 1.32

3.4 Analysis and Results The Super Decisions software is decision-making software based on the AHP and the ANP [18]. In this study, the Super Decisions software is used for multiple reasons. The software provides the users with a platform that has the capabilities of constructing a model, making pairwise comparisons, calculating values, checking inconsistency, and obtaining final results. After constructing the model, the user or the practitioner must make judgments using pairwise comparisons between clusters and nodes. Super Decisions software is used to insert judgments and pairwise comparisons for all clusters and nodes and obtain final priorities. The pairwise comparison process starts with the goal cluster. The judgment process begins with a comparison process between blogging and live streaming clusters in regard to the overall goal. For example, the user inputs a value of 5 for microblogging over blogging. The user here prefers to use microblogging over blogging as a teaching tool. Similarly, the user inputs judgment values to compare all clusters. Table 5 and Fig. 3 show the values and pairwise comparisons among clusters. They show that the user prefers video sharing, social networking, and microblogging. Table 5. Pairwise comparison process.

Blogg ing Live stream ing Micro bloggi ng Social netwo rk Social news Video sharin g

Blo ggi ng 1

Live strea m 1

Micro bloggi ng 1/5

Social netwo rking 1/7

Soci al news 1/4

Video sharin g1/8

1

1

1/5

1/8

1/6

1/9

5

5

1

1/2

1/2

1

7

8

2

1

5

1/4

4

6

2

1/5

1

1/3

8

9

1

4

3

1

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Alaa Kutbi1 and Madani Alomar

Fig. 3. Pairwise comparisons of clusters.

With similar comparison process as above, users also conduct node comparisons allocated in cluster. For instance, practitioners make judgments about Facebook, Google Plus, and LinkedIn regarding which kind of social networking tool or media has the highest priority, is most important, or most effective and efficient to use. Figure 4 shows the results of the node comparisons within the social networking cluster. The instructor likes to share important learning materials using Google Plus and Facebook. Likewise, judgments must be done for all nodes in each cluster to complete all pairwise comparison processes and to complete the circle. The overall ranking is shown in Table 6, with an overall inconsistency or consistency ratio of (CR=0.957). The presence of inconsistency among multiple pairwise comparisons does not necessarily mean wrong judgments unless it exceeds 0.10. Thus, if the consistency ratio is 0.10 or less, the consistency of the pairwise comparisons is considered reasonable.

Fig. 4. Pairwise comparison process within social networking.

The user prefers to use Google Plus and Facebook as social networking tools/media. He also indicates a preference for WordPress as a blogging tool and YouTube as a video sharing tool. However, because the user started the comparison by comparing clusters to identify the importance of each kind, the final nodes’ comparison results and weights can be affected by the weight of its parent/cluster. In other words, the limiting values, the cluster or parent weight multiplied by the node weight, reveal the importance and ranking of several types of social media to the user. For instance, the limiting result, which incorporates the weight of each cluster and node, shows that YouTube, Google Plus, and Twitter are the best tools in each category and among other nodes.

The Importance of Social Media in Education and Prioritizing Process

Table 6. Overall comparison results of nodes and clusters. Cluster Social networking

Facebook

Normalized by cluster 0.36135

LinkedIn

.06504

.018206

Google Plus

.57361

.160570

Node

Limiting .101153

WordPress

.60000

.019248

Blogging

Blogger

.20000

.006416

Video sharing

Live Journal YouTube Vimeo

.20000 .88889 .11111

.006416 .325822 .040728

Live streaming

Periscope

.87500

.025235

Blab

.12500

.003605

Microbloggi ng

Twitter

.88889

.139289

Tumblr

.11111

.017411

Digg

.12500

.016988

Reddit

.87500

.118913

Social news

4. Conclusion, Limitation and Future Work The use of social media in the classroom and in education is no longer a hot topic in many countries because most schools already take advantage of modern technologies. However, the real challenges facing instructors and students are which social media tools are the best to improve the effectiveness and efficiency of educational processes and outputs. According to Ertmer and OttenbreitLeftwich, “teaching is not effective without the appropriate use of information and communication technologies (ICT) resources to facilitate student learning” [19]. However, many factors affect the selection of social media in education. Some of them are related to the ability of instructors and students to deal with different kinds of social media. Previous studies revealed that “teachers need to be able to select the most appropriate ICT resources to enable their students to meet the required learning goals” [19] . Consequently, this study intended to reduce the number of challenges that face instructors when selecting the correct and best social media tools and platforms for

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educational purpose when they use social media in education. It also explored the judgments of a university instructor regarding choosing the right tools for a particular class by introducing a model that helps in increasing the outputs of the education process. A model was constructed using MCDA that follows a systematic and scientific approach to decompose and compare alternatives. Different kinds of platforms and social media were plugged into the model and tested by a university level instructor as shown in the previous sections. The final pair-wise comparisons indicated that You Tube, Google Plus and Twitter are the most important and supportive social media for this particular class. The results of this study are supporting the previous studies that revealed the importance of social media in improving the educational outputs. However, it is hard to generalize these findings because classrooms’ resources, instructors’ and students’ capabilities, accessibilities and availabilities of technology are varying. Moreover, the social media and platforms are the other types of variables that change overtime. Nevertheless, the model was designed to be flexible enough to accommodate different judgments by several instructors and users in different circumstances. It allows users to insert new important nodes/items and eliminate any needless items/nodes when necessary. The proposed model in this study can be improved by implementing the same idea in different circumstances or within different educational institutions. The model can also be used in the future to compare judgments of different educational levels in several countries, which will help in providing a clear picture of the implementation of different kinds of social media in education worldwide.

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Alaa Kutbi1 and Madani Alomar

Finally, the illustrated case in this paper can be improved by conducting a study based on opinions and judgments of more than one instructor.

[10] Boulos, M., Maramba, I. and Wheeler, S., Wikis, Blogs and Podcasts: A New Generation of Web-Based Tools for Virtual Collaborative Clinical Practice and Education (2006). Retrieved 31 October 2014 from: http://www.biomedcentral.com/content/pdf/1472-69206-41.pdf.

References

[11] Moran, M., Seaman, J. and Tinti-Kane, H., Teaching, Learning, and Sharing: How Today’s Higher Education Faculty Use Social Media. Babson Survey Research Group, and New Marketing Labs (2011). Retrieved 12 October 2014 from: http://www.pearsonlearningsolutions.com/educators/ pearson-social-media-survey-2011-bw.pdf.

[1] Smith, S. D., Improving Student Employee Training: A Study of Web 2.0 Social Media Tools as a Delivery Model (Order No. 3518060)(2012). Available from ProQuest Dissertations & Theses Global: Social Sciences. (1033213453). Retrieved from http://search.proquest.com/ docview/1033213453?accountid=14789 [2] Khalaf-Allah, M., “Social Networking Sites”. Official Website of Dr. Mohammed Jaber KhalafAllah (2013). Retrieved March 4, 2014, from http://kenanaonline.com/ users/azhar-gaper/posts/512902 [3] Kutbi, A., How undergraduate female students in the Kingdom of Saudi Arabia perceive social media as a learning tool: An exploratory study (Master’s Thesis). University of Windsor (2015). [4] Grabowicz, P., Web 2.0 and the Rise of Social Media: The Transition to DigitalJournalism ( 2014). Retrieved 7 July 2014, from http://multimedia.journalism.berkeley.edu/ tutorials/digital-transform/

[12] Ishtaiwa, F. and Dukmak, S., “Do Web 2.0 Applications Enhance Learning in Teacher Education in the UAE? An Exploratory Study”. International Journal for Research in Education, 33:1-27 (2013). [13] Yakin, J. and Gencel, E., “The Utilization of Social Media Tools for Informal Learning Activities: A Survey Study”. Mevlana International Journal of Education 3(4): 108-117 (2013). [14] Lin, Y.Y., The 6 types of social media, (2016, May 04), Retrieved Feb.02, 2017 from https://seopressor.com/ social-media-marketing/types-of-social-media/

[5] Wegerif, R., “The Social Dimension of Asynchronous Learning Networks”. Journal of Asynchronous Learning Networks 2(1): 34-49 (1998).

[15] Saaty, T. L., “The Analytic Hierarchy and Analytic Network Measurement Processes: Application to Decisions Under Risk”. European Journal of Pure and Applied Mathematics, 1(1): 122-196 (2008).


[6] Väljataga, T. and Fiedler, S., “Supporting Students to Self-Direct Intentional Learning Projects with Social Media”. Educational Technology & Society, 12(3):5869 (2009).

[16] Chan, F. T. S., Chan, H. K. Lau, H. C. W. and Ip, R. W. L., “An AHP Approach in Benchmarking Logistics Performance of the Postal Industry”. Benchmarking: An International Journal, 13(6): 636-661 (2006).

[7] Hayes, C., Beyond the American Dream: Lifelong Learning and the Search for Meaning in a Postmodern World. Wasilla: Autodidactic Press (1998).

[17] Cheng, E. W. L., Li, H. and Ho, D. C. K., “Analytic Hierarchy Process: A Defective Tool When Used Improperly”. Measuring Business Excellence, 6(4): 3337 (2002).

[8] Spooner, E., Interactive Student Centered Learning: A Cooperative Approach to Learning. Lanham, MD: Rowman & littlefield (2015). [9] Clark, R., “Six Principles of Effective E-Learning: What Works and Why” Learning Solution Magazine, (2002). Retrieved from http://www.elearningguild.com/pdf/2/ 091002DES-H.pdf

[18] Saaty, T. L., "The Analytic Hierarchy Process". McGraw-Hill: New York (1980). Retrieved 24 February 2018, from http:// https://en.wikipedia.org/wiki/ Super_Decisions. [19] Ertmer, P. A. and Ottenbreit-Leftwich, A. T., Teacher Technology Change: How Knowledge, Confidence, Beliefs, and Culture Intersect. Journal Of Research On Technology In Education, 42(3): 255-284 (2010).

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‫‪The Importance of Social Media in Education and Prioritizing Process‬‬

‫أهمية وسائط التواصل االجتماعي في التعليم وتحديد األولويات‬ ‫‪2‬‬

‫آالء كتبي‪ 1‬و مدني آل عمر‬

‫‪ 1‬كلية التربية‪ ،‬جامعة وندسور‪ ،‬وندسور‪ ،‬كندا‪ ،‬و ‪ 2‬كلية الهندسة‪ ،‬جامعة الملك عبد العزيز‪ ،‬جدة‪ ،‬المملكة العربية السعودية‬ ‫‪[email protected]‬‬ ‫دور مهما في التعليم‪ ،‬حيث إن معظم المدارس‬ ‫المستخلص‪ .‬تلعب وسائط التواصل االجتماعية ا‬

‫والجامعات تتوا فر لديها التقنيات الحديثة‪ .‬ومع ذلك‪ ،‬فإن التحدي الحقيقي الذي يواجه أعضاء‬ ‫هيئات التدريس ومن في حكمهم هو اختيار األداة المناسبة لتحسين فعالية وكفاءة العملية‬ ‫التعليمية ومخرجاتها‪ .‬هناك عوامل كثيرة تؤثر على اختيار وسائط التواصل االجتماعي في‬ ‫التعليم‪ ،‬وبعضها يرتبط بقدرة أعضاء هيئات التدريس ومن في حكمهم والطالب على التعامل مع‬ ‫أنواع مختلفة من وسائط التواصل االجتماعية‪ .‬يهدف الباحثون في هذه الدراسة إلى الحد من‬

‫التحديات التي تواجه أعضاء هيئات التدريس ومن في حكمهم فيما يتعلق باختيار وسائط‬ ‫التواصل االجتماعية الصحيحة والمناسبة لألغراض التعليمية‪ .‬يقدم الباحثون في هذه الدراسة‬

‫نموذجا يساعد على زيادة المخرجات التعليمية ألحد المقر ارت الجامعية عن طريق مقارنة البدائل‬ ‫واالختيار‪ .‬تم إنشاء هذا النموذج باستخدام تحليل متعدد المعايير للق اررات‪ ،‬وذلك باتباع نهج‬ ‫منتظم لتحليل ومقارنة البدائل‪ .‬تمت تجربة النموذج المقترح عن طريق عضو هيئة تدريس لمقرر‬

‫جامعي‪ ،‬وقد أدت تجربة النموذج المقترح في هذه الد ارسة إلى اختيار يوتوب وغوغل بلوس‬ ‫وتويتر‪.‬‬ ‫كلمات مفتاحية‪ :‬وسائط التواصل االجتماعي‪ ،‬التعلم اإللكتروني‪ ،‬صنع القرار متعدد المعايير‬ ‫والتحليل‪ ،‬تحسين المخرجات التعليمية‪.‬‬

38

Alaa Kutbi1 and Madani Alomar

JKAU: Eng. Sci., Vol. 28 No. 2, pp: 39 – 50 (1438 A.H./ 2017 A.D.) Doi: 10.4197/Eng. 28-2.4

Entrepreneurship and Saudi Engineering Students: Intentions and Competencies Hemaid Alsulami Industrial Engineering Department, Faculty of Engineering, King Abdulaziz University, Jeddah 21589, Saudi Arabia [email protected] Abstract. In recent years, entrepreneurship has opened many doors and opportunities for individuals and societies alike. In the case of Saudi Arabia, it could reduce the reliance on oil and contribute to the economy diversification. This research paper aims to investigating students’ entrepreneurial intentions such as their level of interest, the time preference of starting their venture and preferences regarding a partnership. Further, it assesses the students' attainment level of skills that are deemed necessary for an entrepreneur to be successful. The research is also evaluating whether a university has any role in providing the students with the necessary skills and in which ways it does that. A survey was used to find answers to the research questions and was distributed to students in different regions of Saudi Arabia. The study found that about 80% of engineering students are interested in having an entrepreneurial career and the primary motivator behind this decision is to make more money than what is provide by a traditional job. Additionally, the majority of students prefer working for a few years before venturing on their own. The results show that skills and competencies such as decision making, effective communication, strategic and analytical thinking, flexibility and leadership were acquired at a better level than skills and competencies such as business acumen, risk taking, financial expertise and time management. Moreover, only 47% of participants believe that higher education schools have a role in equipping the students with the required skills, and the majority of those believe the university has helped them in attaining skills, such as project management skills through business administration courses. Keywords: Entrepreneurship, Engineering Students, Intentions, Competencies, Saudi Arabia.

to tackling the challenges that face their businesses. In the engineering campus of Stanford, there is a strong interest in the field of technology entrepreneurship, and they have a large student body interested in creating practical things that have a positive impact in the world. The fact that Silicon Valley leads excited people to work in the tech industry and support them with required skills to work in their companies in the future is what makes Stanford University stands out in the

1. Introduction Entrepreneurship involves designing, developing, launching and organizing new ventures. Entrepreneurship is characterized by innovation and risk-taking and is an essential part of a society ability to succeed in an ever changing and highly competitive global marketplace. Entrepreneurs are people with ambition who have a vision and determination to achieve their goals. They are equipped with a broad skillset and use innovative approaches

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Hemaid Alsulami

entrepreneurship fields among other universities. Numerous booming businesses around the globe were started by young entrepreneurs and those businesses played a crucial role in job creation and are considered to be a key factor in developing the economy. Startup companies make up 25% in the Kingdom[1], while in 2014, there was a growth in jobs for both Saudi and Non-Saudi. The unemployment rate for nationals remains considerably high and stands at 11.7%[2]. Entrepreneurship could be the answer to decreasing the issue of unemployment especially for females since their unemployment rate is higher than their male counterparts. Further, entrepreneurship can lead to economic growth that is diversified and not heavily reliant on oil. Therefore, the youth should be motivated to become entrepreneurs, and they should acquire the skills to be successful in their endeavor. The aim of this research is to measure the interest level of engineering students and determine what motivate them to pursue entrepreneurship. Furthermore, it aims at evaluating their readiness to start their ventures and create job opportunities for themselves and others by measuring their entrepreneurial skills since there are claims that Saudi graduates do not have the necessary skills to enter the labor force nor start a business venture[3]. Also, the research proposes ways to equip the students with the vital skills they lack to close the skills gap to be prepared to become the next generation of potential entrepreneurs. There is a lack of interest in pursuing an entrepreneurial career that seeks to solve the issue of unemployment and the economic growth in Saudi Arabia. There is also insufficient emphasis given to the importance of training and rehabilitation of students to be qualified and as such create companies and new jobs in Saudi Arabia.

This paper is intends to find answers for the following questions: 1. What are the entrepreneurial intentions among engineering students and the key motivators behind the decision? 2. What is the percentage of students who are equipped with the sufficient entrepreneurial skills and competencies? 3. What is the role of the university in providing the students with the necessary skills? Literature Review The two terms of entrepreneurs and small business owner are used interchangeably but Cuervo et al. [4] indicate that there is a distinction between them and they claim that risk bearing is one of the distinguishing factors as the former tend to be more inclined to take risks while the latter does not. There is also another indication that innovation in addition to the employment of strategic management to grow the business are considered to be the main characteristic that distinguish between the two terms. Entrepreneurial Competencies According to Mitchelmore & Rowley[5], competencies of entrepreneurship are essential to have a growing and a successful business. The core competencies that entrepreneurs possess empower them to succeed and have a fruitful business. Kaur and Bains[6] stated that these competencies take many forms such as follows: • Strategy Competency: The ability to develop a clear vision, plan effectively for the future and set short and long-term goals. • Commitment Competency: Having the drive and dedication to growing a fruitful business.

Entrepreneurship and Saudi Engineering Students: Intentions and Competencies

• Conceptual Competency: Possessing analytical skills and decision-making ability to analyse complexities that may arise and reason the decision by weighing the opportunities and risks. • Opportunity Competency: The ability to recognize and take advantage of the prospective opportunities in addition to understanding the changing needs to be competitive. • Relationship Competency: The ability to communicate clearly and become entrepreneurs to convey the underlying message. This competency also includes the ability to persuade and influence others. • Ethical Competency: Being aware of ethics and ethical dilemmas. • Learning competency: The ability to employ the skills that allow one to adapt to the dynamic nature of the entrepreneur roles. • Technical competency: The ability to utilize the tools and techniques that aresuitable to the business needs. • Personal Competency: The personal characteristics that enhance the effectiveness of the individual in managing challenging tasks. This competency also allows them to identify strengths and match them with opportunities and utilize them in overcoming threats. Moreover, it enables them to identify weaknesses that might hinders the utilization of possible opportunities or worsen the threats. Sorensen and Chang[7] stated that some characteristics and factors which contribute to the business success and these include factors related to psychology such as the aspiration for achievement and personal qualities and also factors related to education and experience which suggests that there is a correlation between the level of education and the performance.

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Nemours studies have investigated the motivation and interest of students in entrepreneurship. Wang and Wong[8] stated that entrepreneurship education and knowledge are the main factors that shape the potential to possess an entrepreneurial attitude. They also state that there are some factors that affect the entrepreneurial propensity, such as gender as males mostly aspire more than females to become entrepreneurs. It was also noted that family business background influences the interest of their children in entrepreneurship. They assert the individuals with self-employed parents are more likely to follow in their footsteps. Baycan and Nijkamp[9] assessed the level of interest in entrepreneurship and its key factors among students in which it was mentioned that many studies suggest that the background is a factor influencing entrepreneurial motivation. This study has found that there is a difference in motivation between genders as female students look for more job alternatives and seek a higher position whereas males showed greater interest in becoming entrepreneurs as well as the high status in society. The study had also found that students from different backgrounds are more interested in becoming self-employed than natives, so this suggests that ethnicity could have an effect on the overall interest. Samuel et al. [10] had investigated the key motivators for students to become entrepreneurs which included utilizing talent, creating job opportunities, earning a living, pursuing their dreams and having job security. This study had also found that there are some obstacles that discourage students from wanting to become entrepreneurs such as lack of savings, lack of experience in business and the difficulty of finding the partners. Moreover, Ahmad et al. [11] found that the majority of students associate innovation, risk taking and capital with the term entrepreneur and stated that the majority of student believes that entrepreneurs are made rather than born.

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The study found that upon graduation, the majority of students prefer working in a company before creating their own business, while some prefer working full time while running their own simultaneously. Innovation is required to solve problems and to maintain competitiveness of Saudi Arabia globally, and engineering is the foundation of innovation. Engineers are prepared to enter the workforce and they thrive in the changes in global economy. Engineers can collaborate effectively as leaders. In addition to their systematic thinking, technical and analytical background, they have the ability to realize and seize opportunities under any economic and social conditions[9]. All of these innovative and entrepreneurial skills should be educated as part of engineering education and it is the responsibility of engineering colleges and educators to gain these qualities in students. In this research, the role of engineering education in habilitating the students for entrepreneurship was investigated, by analysis the efficiency of student skills and engineering faculty programs in entrepreneurship field. Then we offer our perspective on the future landscape for innovation and entrepreneurship in engineering education. Engineers need to be qualified to understand and contribute to the market and business field. The engineers who have entrepreneurial skills and start their business after graduation have high level of experience in product design and development, prototyping, technology trends, and market analysis[12]. These skills support them to success in their business and engineers, who join companies are better prepared to become competent managers and team members. Entrepreneurship education teaches engineering students in all disciplines the knowledge, tools, and attitudes that are

required to identify opportunities. Students who take part in entrepreneurship programs as undergraduates gain perspicacity not available from traditional engineering education, such as working in and managing interdisciplinary teams, communicating effectively, understanding business basics, thinking critically and solving open-ended problems[13]. 1.1 Methodology The study uses survey as a method to collect the required data. A pilot study was conducted on sample of engineering colleges students in King Abdulaziz university to test the clearance of the survey questions. A group of 20 students were requested to fill the questionnaire and based on their submission and feedback the survey was revised. In addition, the survey was sent to three experts to validate it in order to improve it. Then, the survey was distributed in an online form to engineering students in different regions of Saudi Arabia such as western, middle, and eastern regions. To reach out students in different universities Emails and messages feature in social media applications (such as WhatsApp, Twitter, Instagram, Facebook) were sent to representatives of these universities and they were asked to circulate it between students in engineering colleges. After filling the survey, students just click submission button and survey will be submitted and saved in an online data base. It takes three months to collect the required data from different regions. The survey identified the intentions of students regarding entrepreneurship such as their interest level in becoming entrepreneurs and the key motivators behind that decision. Further, it investigated the entrepreneurial competencies and skills that the students possess. 1.2 Findings and Discussion After data collection was completed, the Microsoft Excel was used to analyze the data.

Entrepreneurship and Saudi Engineering Students: Intentions and Competencies

More than 3000 responses were collected 40 % from western region, 30 middle region and 30 percent from the eastern region. From this sample 90% were male students while 10 % female students which is reasonable, since most of engineering colleges in Saudi Arabia teaching only male students except few universities such as King Abdulaziz University. Around 120 responses were excluded based on the validation processes. The Likert Scale was used to evaluate participates level of agreement. A scale of 1 – 5 used as 1 means least applicable and 5 means most applicable. The following sections represent the responses of each item in the survey. 2. Entrepreneurial Intentions 2.1 Interest Level To answer the research question regarding entrepreneurial intention, the results show that 80% of the engineering students have interest in pursuing entrepreneurial career. From the sample, only 2% of participants show that they are not very interested to be entrepreneurs, 31% are somewhat interested, 37% are interested and 30% are very interested. The result indicates that students have shown some level of interest that is variable since some students have strong interest, as shown in Fig. 1. This results the high percentage of Saudi students in engineering colleges to become entrepreneurs comparing to previous studies that showed Saudi were interested in looking for a job instead of starting their own businesses. 2.2 Working Preferences Figure 2 shows that 25% of the interested students in entrepreneurship prefer starting their own business individually, while 75% prefer working with partners. This preference could be because that many courses in engineering schools have projects that are

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team based and students feel that their performance is better when working with a group. This result is an indicator of the possibility that the proportion of partnership business and private companies in the future will increase in Saudi Arabia. 1.3 Time of Pursuing Entrepreneur Career Figure 3 shows that of those who are interested in becoming entrepreneurs, 10% want to start their own business directly after graduation, 20% while studying, 20% prefer working after graduation and start their own business as a part time simultaneously while 50% of the students prefer working after graduation for a period then start their own business. This finding implies that students want to get job experience before venturing on their on to learn some skills and increase their entrepreneurial success rates. The results show that most of students in the big cities such as Riyadh and Jeddah prefer to get experience in big companies to help them start their business in a better way. The other reason because the availability of job opportunities in these cities. 3. Entrepreneurship Motivators Figure 4 shows that of those who are interested in becoming entrepreneurs, 54% reported their interest because they want to be their own boss, 64% to make more money, 43% to create job opportunities in the community, 46% to utilize their talent, 12% to follow in their parent’s footsteps, 37% to give back to the community while 62% reported their interest because they want to see their idea come to reality. In this question, the participants were allowed to choose their reason why did they are interested in entrepreneurship in order to find out the most three factors that affect their interest. The results show that following reasons are most three reasons why Saudi students in Engineering colleges keen to establish their own businesses:

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1. To make more money. 2. To see my idea for new products, service or improve products selling in the market. 3. To be my own boss. 4. Obstacles of Pursuing Entrepreneurship The obstacles reported by students that might hinder them from pursuing entrepreneurship are lack mentorship as reported by 33%, lacking financial support as reported and lacking knowledge and skills and finding business partners as reported by 51% and 18% of the respondents respectively as

seen in Fig. 5. This finding was expected, since the main factor that hinders some people from pursuing entrepreneurship is due to finances. The results show also those students who replie of lacking of knowledge and skills are students who answered they are not interested in pursuing entrepreneurship, and students who were interested but they are juniors in the engineering college. Students who shows they are lack of mentorship most likely answered they are very interested or interested in entrepreneurship but they need mentors to help them to set up their business.

Fig. 1. Interest level of students in entrepreneurship.

Fig. 2. Working preferences.

Entrepreneurship and Saudi Engineering Students: Intentions and Competencies

Fig. 3. Time of starting the business.

Fig. 4. Motivators for the interest in becoming an entrepreneur.

Fig. 5. Potential obstacles.

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5. Entrepreneurial Skills In Table 1, students were asked to evaluate their attainment of the skills by selecting a number from 1 -which implies that the skills are not attained by the students at allto 5 -which implies that the skills are attained by the students at a good level. Of the skills that are identified to be necessary for a successful entrepreneurial career, the table shows that most of students have rated themselves lower than 4 approximately 54% as shown in Table 1, which is almost consistent of the percentage of students who selected lacking of knowledge and skills. Business acumen is the least possessed skill with 4% of the student having an advanced level, while leadership skills are the highest acquired at an advance level with 23% of the students. This finding could be due to the fact the students do not have business related hands-on experience since many have their first experience with real life business during their internships which is during the last few semesters of college. The percentage of students possessing skills at an intermediate level or higher is greater for students interested in pursuing an entrepreneurial career than their counterparts as shown in Table 2. Thus, it can be concluded that students with good level of skills are more likely to pursue entrepreneurship particularly business acumen and risk taking because all other skills are required for any other type of work life 6. University Education Role To answer the research question regarding the role of universities in equipping the students with the necessary skills, it was found that about 43% of the engineering students agree that universities have a role in equipping their students with the necessary

skills, since many offers electives in management subject as shown in Fig. 6. Therefore, it can be concluded that universities have impact on the qualification of entrepreneurs as well as the interest of engineering students. Of those who think universities have a role in equipping their students with the necessary skills, 24% think the skills are acquired from extracurricular activities, while the majority thinks the skills are acquired through business management courses as shown in Fig. 7. This is because many students acquire skills from formal ways rather than informal ways such as extracurricular activities. From the survey, it was found that 51%, 78%, 36%, 56% and 56% of them think universities helped them in acquiring financial, project management, market research, designing and marketing skills, respectively as shown in Fig. 8. The percentage of student with project management skills is the highest, which could be due to the fact the many engineering schools offer courses covering these skills. On the other hand, the percentage of students who think universities taught them market research skill is the lowest. This finding was not expected since engineers have to understand the requirements of the customer to meet their expectation. 6. Conclusion In conclusion, this study explores intentions of engineering students regarding entrepreneurship. The study shows that a staggering number of students intends on becoming entrepreneurs at some point in their life whether during university, after graduation directly or after some time or balancing between a job and an entrepreneurial project simultaneously. The study found that about 80% of engineering students are interested in having an entrepreneurial career and the

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Entrepreneurship and Saudi Engineering Students: Intentions and Competencies

primary motivator behind this decision is to make extra income than what is earned by a traditional job. The majority of students prefer working for a few years before venturing on their own. The results show that skills and competencies, such as decision making, effective communication, strategic and analytical thinking, flexibility and leadership were acquired at a better level than skills and competencies such as business acumen, risk taking, financial expertise and time management. Moreover, only 47% of participants think that higher education schools have a role in equipping the students with the required skills, and the majority of those believe the university has helped them in attaining skills, such as project management skills through business administration courses. Therefore, it is recommended that universities introduce entrepreneurship course to enhance student skills to start their businesses as 51% of students selected lacking of knowledge and skills as one of the obstacles that are facing when they are willing to start their businesses. It is also recommended that university provides new degree programs in entrepreneurship for those who intent to purse their bachelor or master degrees in this field.

Moreover, the university may offer training courses in entrepreneurship which includes accounting for non-accountants, marketing for non-marketers, project management, feasibility studies and any related courses. Based on the results, it is recommended to establish business accelerators within university to encourage students build their business ideas. In addition, the university may establish business incubators to host won ideas from the accelerators for at least two years until it becomes mature venture. Accordingly, university with private sector partnership can reserve seed funds for those projects and work with local government agencies to facilitate their paper works. Also, University may collaborate with chamber of commerce to motivate private sectors to buy from those entrepreneurs. To further enhance the outcomes of this study, it is recommended that student from other non-engineering disciplines be included in a future study. Further study the impact of the Saudi culture and government regulations on entrepreneurship as a factor affecting the interest and motivation of university students in Saudi Arabia is required.

Table 1. Students agreement level on skills acquired at good level. Skills

1(Least acquired)

2 (Least 3 4 (mostly acquired) (Neutral) acquired)

5 (Fully acquired)

Decision making

14%

11%

22%

36%

16%

Effective Communication

13%

14%

23%

29%

21%

Business Acumen

16%

22%

29%

30%

4%

Risk Taking Strategic and Analytical Thinking

20%

20%

24%

25%

11%

12%

11%

26%

34%

16%

Adaptedness and Flexibility

14%

9%

28%

30%

20%

Financial Skills

19%

21%

21%

27%

12%

Time Management

14%

17%

25%

26%

18%

Leadership

15%

11%

16%

34%

23%

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Hemaid Alsulami

Table 2. Students agreement level on skills acquired at an intermediate level or higher

Skills

1(Least acquired)

2 (Least acquired)

3 (Neutral)

4 (mostly acquired)

5 (Fully acquired)

Decision making

12%

11%

19%

38%

20%

Effective Communication

10%

15%

24%

29%

23%

Business Acumen

8%

24%

31%

32%

5%

Risk Taking

18%

17%

24%

29%

13%

Strategic and Analytical Thinking

10%

11%

29%

35%

17%

Adaptedness and Flexibility

10%

11%

24%

35%

21%

Financial Skills

14%

19%

23%

31%

13%

Time Management

10%

20%

23%

29%

19%

Leadership

12%

13%

12%

36%

27%

Fig. 6. University education role.

Fig. 7. Ways of universities to equip students with the skills.

Entrepreneurship and Saudi Engineering Students: Intentions and Competencies

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Fig. 8. Skills that universities equip its students with. References [1] EY G20 Saudi-Arabia Report (2013). Retrieved from http://www.ey.com/Publication/vwLUAssets/EY-G20country-report-2013-Saudi-Arabia/$FILE/EY-G20country-report-2013-Saudi-Arabia.pdf [2] International Monetary Fund Saudi Arabia Report (2015, September). Retrieved from: https://www.imf.org/ external/pubs/ft/scr/2015/cr15251.pdf [3] How will the GCC close the skills gap? (2015). Retrieved from http://www.ey.com/Publication/vwLUAssets/EYgcc-education-report-how-will-the-gcc-close-the-skillsgap/$FILE/GCC%20Education%20report%20FINAL%20 AU3093.pdf [4] Cuervo, Á., Ribeiro, D. and Roig, S. (Eds.). Entrepreneurship: Concepts, Theory and Perspective. Springer Science & Business Media (2007). [5] Mitchelmore, S. and Rowley, J., Entrepreneurial competencies: a literature review and development agenda. International Journal of Entrepreneurial Behavior & Research, 16(2): 92-111(2010). [6] Kaur, H. and Bains, A., Understanding the concept of Entrepreneur Competency. J. Bus. Manag. Soc. Sci. Res., 2: 31-33 (2013). [7] Sorensen, J. and Chang, P., Determinants of successful entrepreneurship: A review of the recent literature. Available at SSRN 1244663 (2006).

[8]

Wang, C. K. and Wong, P. K., Entrepreneurial interest of university students in Singapore. Technovation, 24(2): 163-172. (2004).

[9]

Baycan, T. and Nijkamp, P., Students’ interest in an entrepreneurial career in a multicultural society. Research Memorandum, 34 (2011).

[10] Samuel, Y. A., Ernest, K. and Awuah, J. B., An assessment of entrepreneurship intention among Sunyani Polytechnic Marketing students. International Review of Management and Marketing, 3(1): 37 (2013). [11] Ahmad, F. S., Baharun, R. and Rahman, S. H. A.. Interest in entrepreneurship: An exploratory study on engineering and technical students in entrepreneurship education and choosing entrepreneurship as a career. Project Report, Faculty of Management and Human Resource Development, Skudai, Joho (2004). [12] Gorman, G., Hanlon, D. and King, W., Some research perspectives on entrepreneurship education, enterprise education and education for small business management: a ten-year literature review. International Small Business Journal, 15(3): 56-77 (1997). [13] Byers, T., Seelig, T., Sheppard, S. and Weilerstein, P. Summer Issue of the Bridge on Undergraduate Engineering Education.‫ ‏‬National Academy Of Engineering, Washington, DC, Vol. 43, No. 2.

‫‪Hemaid Alsulami‬‬

‫ريادة األعمال وطالب الهندسة السعوديين‪ :‬الرغبة والكفاءات‬ ‫حميد السلمي‬ ‫قسم الهندسة الصناعية‪ ،‬كلية الهندسة‪ ،‬جامعة الملك عبد العزيز‪ ،‬جدة ‪ ،21589‬المملكة العربية السعودية‬ ‫‪[email protected]‬‬ ‫المستخلص‪ .‬في السنوات األخيرة‪ ،‬فتحت ريادة األعمال العديد من األبواب والفرص لألفراد‬

‫والمجتمعات على حد سواء‪ .‬هنا في المملكة العربية السعودية‪ ،‬يمكن أن تقلل ريادة األعمال‬

‫االعتماد على النفط وتسهم في تنويع االقتصاد‪ .‬تهدف هذه الورقة البحثية إلى التحقق من رغبات‬

‫الطالب الريادية‪ ،‬مثل مستوى اهتمامهم‪ ،‬وتفضيل الوقت لبدء مشروعهم وتفضيالتهم فيما يتعلق‬ ‫بالشراكة‪ .‬وعالوة على ذلك‪ ،‬فإنه يقيم مستوى تحصيل الطالب من المهارات التي تعتبر ضرورية‬ ‫لنجاح رواد األعمال‪ .‬كما يقوم البحث بتقييم ما إذا كانت الجامعة لها أي دور في تزويد الطالب‬ ‫بالمهارات الالزمة لبدء األعمال‪ .‬في هذه الدراسة تم استخدام االستبانة لجمع البيانات ألسئلة‬ ‫البحث‪ ،‬وتم توزيعها على الطالب في مناطق مختلفة من المملكة العربية السعودية‪ .‬بينت نتائج‬ ‫الدراسة أن حوالي ‪ ٪80‬من طالب الهندسة يهتمون بامتالك شركاتهم الخاصة‪ ،‬والحافز الرئيسي‬ ‫وراء هذا القرار هو كسب المزيد من المال أكثر مما يوفره العمل التقليدي‪ .‬باإلضافة إلى ذلك‪،‬‬ ‫فإن غالبية الطالب يفضلون العمل لبضع سنوات قبل المغامرة بالبدء في أعمالهم الخاصة‪.‬‬ ‫وتظهر النتائج أن المهارات والكفاءات‪ ،‬مثل‪ :‬صنع القرار‪ ،‬والتواصل الفعال‪ ،‬والتفكير والتحليل‬ ‫االستراتيجي‪ ،‬والمرونة والقيادة‪ ،‬قد تم الحصول عليها بمستوى أفضل من المهارات والكفاءات‬

‫مثل الفطنة‪ ،‬والمخاطرة‪ ،‬والخبرة المالية وادارة الوقت‪ .‬عالوة على ذلك‪ ،‬يعتقد ‪ ٪47‬فقط من‬ ‫المشاركين أن الجامعات لها دور في تزويد الطالب بالمهارات المطلوبة‪ ،‬ويعتقد معظمهم أن‬ ‫الجامعة قد ساعدتهم في الحصول على بعض المهارات‪ ،‬مثل إدارة المشاريع‪ ،‬وذلك من خالل‬

‫مواد اإلدارة التي درسوها‪.‬‬

‫الكلمات المفتاحية‪ :‬ريادة األعمال‪ ،‬طالب الهندسة‪ ،‬الرغبة‪ ،‬الكفاءات‪ ،‬المملكة العربية السعودية‪.‬‬

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JKAU: Eng. Sci., Vol. 28 No. 2, pp: 51 – 73 (1438 A.H./ 2017 A.D.) Doi: 10.4197/Eng. 28-2.5

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study Ahmed M. Badeeb, Reda M.S. Abdulaal and Abdullah O. Bafail Industrial Engineering Department, Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia [email protected] Abstract. As a result of the recession in Saudi Arabia, the manufacturing companies start thinking to reduce the operational cost and increasing the productivity through lean manufacturing principles. This paper is focused on increasing the productivity of a paint manufacturing company through implementing some of the lean manufacturing techniques. First, Value stream mapping analysis carried on throughout the manufacturing process and the areas of improvements in the company has been identified using fishbone diagram. Second, Work Place Organization (5S), Single Minute Exchange of Dies (SMED), Work Standardization and Kanban are the lean manufacturing techniques selected to solve different problems facing the company in these areas of improvements. A systematic approach of each technique implemented to measure its effect on the company productivity. It is observed that, applying (5S) and (SMED) techniques in the filling process decreased the changeover time by 59% and increased the daily productivity. Pareto chart recommended using work standardization in the charging process led to reduce the defects batches by 57%. Kanban system eliminated the shortages of semi-finish product and increased the output of the pre-weighing batches by 57%. In addition, overtime hours reduced by 77% and waste handling reduced by 85% and 53% for the non-hazardous and hazardous waste respectively. Keywords: Paint manufacturing, Lean manufacturing techniques, Single minute exchange of dies, Work place organization (5S) technique, Value stream mapping.

in the year 2016 due to various reasons. This decrease affected the global economy, especially the countries that highly depend on oil production. As a result of which, the industrial sector was affected negatively including the paint manufacturing companies. Management teams started thinking of increasing the production and decreasing the waste in order to overcome this tough period and continue its growth. Lean manufacturing techniques are suitable for such a period where there is no much need to invest in new

1. Introduction Paints manufacturing companies in Saudi Arabia grew rapidly in the last few decades because of a boost in the national economy due to high prices of oil, which led to flourishing projects in both government and private sectors. Companies, during this period reached to their highest level of performance in all aspects, like products, sales, revenues and profit. Unfortunately, when the oil prices decreased globally in the last two years (20162017) so rapidly that it reached its lowest level

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Ahmed M. Badeeb et al.

technology or human’s resources. Identifying the bottlenecks around the manufacturing process will help a lot to reduce the waste and the unnecessary tasks performed by the workers. Selecting the suitable lean manufacturing techniques and applying it in the highly affected area could reduce waste and increase the production [1]. The next sections, of this paper, will illustrate the main principles of lean manufacturing and its application in one of the leading Saudi paint manufacturing companies followed by the results and conclusions from real case study. 2. LIterature Review The concept of lean starts when Toyota first introduced and implemented the Toyota Production System which is identified as the “origin” of lean [2]. Lean thinking considers things that the customer does not pay for a waste, while Lean manufacturing is an operational system that eliminates wastes and saves time for the manufacturing company. According to Wang [3], many companies are trying to apply lean principles due to economic issues in the current world. Earlier, people lacked the knowledge to embrace lean manufacturing in their companies but now people have come to realize that lean manufacturing plays a critical role in reducing waste when combined with other resources of production [4]. Lean is aimed to bring overall change in a manufacturing plant rather than changing some few aspects within the organization [5]. Many lean tools and techniques applied in paint manufacturing companies such as Work Place Organization (5S), Single Minute Exchange of Dies (SMED), Work Standardization, and Kanban. 2.1 Workplace Place Organization (5S) A good workplace organization is paramount to ensure there is an easy operation within the workstation [6]. The workplace place organization (5S) method serves very

important functions in an organization that wants to cut unwanted production cost and improve the company's production. This method ensures every activity in the right order within the working environment. The technique supports other techniques like Just in Time (JIT) and Total Quality Management (TQM). The 5S notation comes from implementing five processes successively in the work place titled: Sort, Set in order, Shine, Standardize, and Sustain [7]. A clean environment ensures that the whole process of production is carried out smoothly and that is shine [8, 9]. 2.2 Single Minute (SMED)

Exchange

of

Dies

SMED is one of the various techniques used in the process of industrial manufacturing. It usually looks to reduce the time taken to accomplish changeover in equipment. Changeover time usually hides waste in the form of motion, transportation, waiting, defects and overproduction. SMED is best implemented when the teams that are involved in changeovers individually responsible for a specific machine [10]. It is powerful technique to reduce the waste in processing activities and to make improvements within the immediate time possible [11]. The details of the changeover process are marked and external activities separated from each other [12, 13]. 2.3 Work Standardization These are guidelines in lean management whereby procedures to be followed during production process are drawn [14]. The aim of work standardization is to make sure all the employees/workers can perform a specific task or carry on a long process from (a) to (z) correctly and as per the required quality. Standard form of work standardization firstly creates and then applies to all tasks. The form should be as simple as possible.

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

2.4 Kanban System Kanban basically as a lean manufacturing system that controls inventory and the supply chain purposely to improve efficiency. The implementation process of Kanban is a bit discouraging. However, Kanban is incremental and improve as time goes by. Changes are made when it happens and the initial steps are the most important one. Building a Kanban board is usually the second step in Kanban implementation [15]. The main principles that should be followed during the implementation of Kanban include visualization of workflow, limiting the issues being worked on, and optimizing the cycle time [16]. 3. Stages of Paint Manufacturing One of the biggest Saudi companies, as a leader in paints manufacturing industries, wants to tackle the bottlenecks in the manufacturing process and increase the productivity. Lean manufacturing principles adopted to achieve the company's goals. A study team is formed to identify the bottlenecks in the manufacturing process, evaluate the problem and then suggest suitable lean techniques to implement. The study team divided the manufacturing process into four stages, which are: (1) Pre-weighing stage, (2) Charging stage, (3) Laboratory stage, and (4) Filling stage. The team has decided to ignore the laboratory stage and focus their efforts and studies on the other three stages as it has more potential for improvement. A process flow chart was conducted on each stage in order to illustrate the current process flow sequence followed by value stream mapping for the complete manufacturing process excluding Laboratory stage. 3.1. Pre-weighing Process The pre-weighing process is simply where the raw materials are pre-weighed in order to start

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the manufacturing process. The Raw Material (RM) is divided into two categories:  Fast and common raw material: These raw materials are always available in the shop floor and the operators will do the preweighing themselves as instructed in the charging recipe.  Slow moving raw materials: These raw materials are pre-weighed in the raw material store just to ensure the exact quantity are given as per the recipe and it will be kept on a pallet waiting for the call from the shop floor operator.  The daily capacity of the production department is to make an average of 24 batches. Once a filling process is completed, the charging operator will ask the forklift operator to bring the pre-weighted material from the raw material store for the next batch (Fig. 1). 3.2 Charging Process The charging process is a core of the manufacturing process where the raw material is being charged to the dissolver in order to make the assigned product. It is called as charging process because the operators will start charging the raw material one by one to the dissolver or the mixer. As mentioned in pre-weighing step, once the filling process complete the charging operator will give a signal to the forklift operator to deliver the next pre-weighing batch to the shop floor. Once it reaches, the charging process will start. The first step of the charging process is to inspect the tank condition, according to the next desired product to be manufactured, the operator will decide whether the tank needs to be cleaned or not. If the tank is ready for charging, the first RMs to be added is the water and the binder from the Programmable Logic Controller (PLC) room. The addition of these RMs will occurred automatically through

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pipes, which are connected directly to the dissolver. The extenders will be added one by one using the help of stacker and fixed crane (fixed crane is available in each dissolver) where the stacker will be used to transfer the extenders which come in a bag of 1000 kg, and the crane will lift the bag and put it closer to the manhole. Once the addition of the extenders is completed, the operators will preweigh the next additives, which are placed in cubic plastic tanks with a valve and a weighing scale. The additive will be mixed with water before adding it to the dissolver.

After the mixing time is completed, it will be added through big pots into the dissolver. Upon the completion of the mixing process, a sample of the paint will be taken in order to test the grinding stage on a paper panel. A 200 Micron will be applied on the panel and then will be kept inside an oven for an average of 20 minutes. If the grinding test passed, then another sample will be submitted to the lab in order to inspect the other specifications, such as the viscosity, PH-value, hiding power and the application structure (Fig. 2).

Yes No

Fig. 1. The implementation steps of pre-weighing process.

3.3. Filling Process Filling process is the last main process in the manufacturing whole process. The filling process comes exactly after the approval of the item under charging. Laboratory will give green signal to the production operators to start filling process (i.e. once the submitted sample meets the corporate specification

range). Filling process is containing the following small tasks:  Define the net weight and gross weight for the batch to be filled (operator not lab).  Arrangement of packing materials. (KANBAN)  Arrangement of empty pallets.

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

 Labelling of packing materials. (One piece flow)  Feeding packing materials into the filling line.

55

 Start filling  Placing the drums into pallet  Moving the full pallets into the temporary storage area.

No Yes

Fig. 2. The implementation steps of charging process.

The lab team will decide the net weight and gross weight according to the approved batch’s specific gravity and density. All the tasks described above carried out manually except the filling of paint into the pails. The arrangement of packing materials, empty pallets and moving the pallets into the temporary storage area carried out using stackers for transferring. Placing the pails into the pallets is semi-auto task where an operator will use air lifter machine that sucks the pail’s top and then placing it into the pallets, where a worker operates the air lifter machine. The number of the filling operators varies according to the production line capability and the packing size to be filled (i.e. small, medium and large packs). Labelling process is fully a manual task where the filling operators will past

the label on each pail manually. According to several process observations for the three stages of the manufacturing process, the filling process is the longest process in most of the products. Figure 3 illustrates the filling process. 4. The Proposed Methodology The formed study team recommended using some of lean manufacturing techniques to increase the company’s productivity. The team starts with data collection followed by data analysis and ends with implementing four lean manufacturing techniques. 4.1. Data Collection Value Stream Mapping (VSM) technique is used to collect the data for the

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completely manufacturing process to identify the waste sources and the area of improvement. The total water base production lines are 13 and thus, the focus was on the fast moving production line. As the overall process of manufacturing paints is similar in term of activities required to carry out the whole manufacturing process. Figure 4, explain the value stream mapping which the team has conducted for one production line that is consider as the most utilized production line. The team conducted observation for the manufacturing process several times and the findings below are the average result.

Pre-weighing Process:  Pre-weighing Cycle time per batch: 25 min  Number of batches pre-weighed per shift: 19 batches  Total waiting time (non-value added): 8 min  Total Movement time (non-value added): 6 min  Total non-value added time: 14 min  Total value added time: 11 min  Pre-weighing process Takt time (based on 32 batches): 15 min/batch Charging and Filling Process:

The total manufacturing time is equal 300 minutes ≈ 5 hours where the value-added process time is 219 minutes while the nonvalue added time is equal to 88 minutes. The goal is to reduce the non-value added time and thus reducing the total manufacturing process time. The outcomes of the VSM can be summarized in the following points:

 Charging process cycle time: 125 min  Filling Process Cycle time: 150 min  Total Waiting time (non-value added): 30 min  Total Movement time (non-value added): 25 min  Total non-value added time: 55 min  Total value added time: 220 min

No

Yes

Fig. 3. The implementation steps of filling process.

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An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

Fig. 4. Steps of Value Stream Mapping.

4.2. Data Analysis

 Changeover time

Identifying Bottlenecks, is a process or operation that is less than average pace of the other process/operations in the same sequence. The following points were taken, as the most area, which needs for improvement (based on brainstorm session):

 Waiting for shop orders to start preweighing

 Number of batches pre-weighed per shift

 Time consumed charging process

by

movement

in

 Waiting for packing material during filling

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 Operators skills and knowledge of certain process/task  Stoppage of production due to shortage of semi-finish RM Fishbone diagram created to clarify and present the main root causes that affect the productivity and the waste management. In general, Fishbone diagram is a tool used to

identify the causes and contributors to a specific problem. The team members came up with many causes for each category. The breakdown of production filling line is one of the causes that lie under the machine category. The productivity is also affected by the skills of the operators who are running the machine. Operator’s skills lie under the category of people and so on (Fig. 5).

Manufacturing process Location: Water base factory Problem: Productivity efficiency

Machine

Management Pre-weighing not ready

changeover time

Poor Planning

Shortage

brakedowns

Distribution

Defect

Capacity

Storage capacity

Man-power allocation

Capability

Harmfull

Temperature

Workload

Cycle time

Space/Area

Physical capability

Waste Handling Waste generation Environment

Material

High mix of SKUs

Operators skills Absentesiem

People

Cleaning Movement

Process

Fig. 5. Fishbone for the case under study.

Two brainstorming sessions have conducted. The first one is to find out what is the area of improvement for each of the three stages of the manufacturing process (i.e. increase the number of pre-weighed batches per shift). The second session performed to find out what are the best possible solutions that can affect achieving the defined improvements. The overall goal is to increase the productivity, reduce workload and better management of waste. Below listed are suggestive improvements:

 Increase the number of pre-weighed batches per shift  Reduce the movement for pre-weighing and charging process  Reduce the waste generation during filling process  Reduce the cycle time for the preweighing and charging process  Reduce the non-value added tasks  Eliminate the production stoppage due to RM shortage

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

 Reduce the changeover time for the filling process  Reduce the human mistakes due to lack of skills or knowledge  Reduce the workload on operators 4.3. Lean Implementation Four lean manufacturing techniques selected as the most appropriate in order to achieve the company’s goals and to increase the productivity:    

Work place Organization, 5s Single minute exchange of dies, SMED Work Standardization Kanban 5. Results and Discussions

5.1 The Results Obtained Using Workplace Organization Technique (5S) The impact of implementing 5S technique in the raw material store and the pre-weighing area was significant. The team has changed the location of several raw materials and defined a location for all the tools and equipment’s. The unwanted or expired raw material was removed from the place, which was making noise and delaying the movement of the workers in the area. Unnecessary tools such as cleaning tools, unused weighing scales and defected trolleys were sent to scrap after the approval of area owner. Paper handling was further improved where a shelf of multiple racks were fixed on the wall, and marked for each work center. All the shop orders for a certain W/C placed in its designated rack according to the sequence and priority (need date). The waste was eliminated. The following paragraphs show the area improved by applying 5S technique and its impact on the production productivity. Trolleys and stackers become easy to accessible and to find (Fig. 6). Designated place made to keep all the trolleys and

59

stackers. This step organizes the place and let workers perform their tasks much way easier and faster than before. The huge impact of defining a designated place for the stackers and trolleys in the pre-weighing area occurred as the travel distance by the pre-weighing operators reduced. Pre-weighing operators become able to perform their task efficiently and consistent. Each product in the production floor has its own filling size and correspondingly has its own layout for filling. So, having one filling line for different products a complex process and leads to time-consuming for the preparation of the layout especially when the area is congested. Operators usually take long time for moving the filling line to the desired layout so they can start filling. The team has sort the area and the filling line according to the size of packing to be filled. After several meetings and GEMBA (A Japanese word that literally means "the real place", used in business process improvement contexts to refer to the place where value is added, such as a manufacturing area or a workshop) on site they have decided a standard layout for each filling size of the packing material. They came up with 3 standard layouts for small, medium, and large packs. After finalizing the standard layouts, the layout for each size of packs marked using yellow tape as illustrated in Fig. 7. In Fig. 8, the filled finish goods are placed on pallets waiting to be transferred to the conveyor by stackers. For each filling line, the area of placing the pallets has been marked. This step of making designated area for the filled pallets help the filling team to better organize the filling floor and it gives better reading for the supervisors. In addition, it worked like a Kanban for the pallets as the stacker operator can see that the designated area for a specific filling line is full of pallets and thus he has to drive the stacker and move the pallets to the conveyor. In fact, even safety

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has been considered by marking the specific area for the pallets, where there will be no misplacement of pallets on the emergency lines or green path allowing the operators to move smoothly to the fire assembly point when fire alarm starts. During preventive maintenance or any breakdown, maintenance team or senior operators have to bring their own tools and equipment to fix the problem that is consuming time of movement. Several meetings held with the maintenance team and they have concluded that only specific tools are necessary to fix 80% of any breakdown of machine or to complete the preventive maintenance job. Tools has been provided to each machine whether its filling line or dissolver or any other machinery that operated by workers. Tools have been kept in toolbox nearby each machine and the keys kept with the team leader (Fig. 9). Figure 10 shows the different raw materials in the raw material store and the preweighing area. The area has fully reorganized and the raw materials have been placed in a way that reduces the movement of workers. In addition, designated line made for each raw material to ease the process of reading the area and easily caught any shortages or near to shortage of raw material. Future plan is to set re-order point for each line to better read the area and control the stock of the raw material. Waste generation and treatment are costing the company a lot of money. The generated waste is divided into two categories that are hazardous waste and non-hazardous waste. Hazardous waste includes any waste that have contaminated by paint or any chemicals, while the non-hazardous waste is mostly the paper bags, plastics, uncontaminated packing material, nylons, etc. All stages of manufacturing generated waste

that needs to be collected and sent to the designated area. Previous practice shows that types of non-hazardous waste were collected in big cartons. After that, they placed on pallets in order to send to the non-hazardous huge waste trash. Whenever the trash bin reaches to certain limit, the HSE (Healthy, Safety, and Environment) team will call the non-hazardous agent to visit the factory and remove all the non-hazardous waste. The company has to pay the agency per kilograms. HSE team has made several visits to different agency dealing with the non-hazardous waste and agreed with one agency to take the non-hazardous waste with no cost if segregated properly. The agency and the company agreed to divide the waste into three main categories that are: 

Plastic waste (Nylons, paper cups, etc.)



Packing material



Jumbo and paper bags

The team has created new trash bins nearby workstations (Fig. 11), and ask the operators and cleaners to segregate the waste once it generated immediately so no need to accumulate all the waste and then segregated on the site as expected to take long time. Figure 11 shows the types of waste bins crated by the team where the blue bins made for the nylons bags and the green bins for the paper bags. Segregating the waste according to the new three categories described above, the waste handling become easier and the cost of handling the hazardous and non-hazardous waste decreased due to the changes in the disposing methodology where before the nonhazardous waste being collected by a supplier, the company has to pay the supplier for taking the non-hazardous waste. However, the team members were able to find a contractor who has willingness to buy the waste if properly

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

segregated (i.e. cartons, plastic, nylons etc.). So, the company has to stop paying the contractor for removing the waste and the opposite scenario occurred where the contractor pay the company for the waste he takes. In addition to the non-hazardous waste, the amount of the hazardous waste reduced due to the implementation and the close monitoring of the hazardous waste collected. The team has reinforced the differences between the hazardous waste and nonhazardous waste and the cost of treating each kind, the 5s teams stopped the wrong behavior of putting a non-hazardous waste into the hazardous waste area and causing the contractor to ask for more money, which is of

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waste money company is paying. Table 1 and Fig. 12 illustrate the waste disposal progress. Table 1. Monthly waste disposal in 2017. Month

Hazardous waste (KG)

Non Hazardous waste(KG)

January February March April May June July August September October November December

6542 5990 6503 14151 7002 3207 5988 6221 5240 5650 6833 3122

24090 22368 21951 21824 21782 15549 23960 21780 21220 23100 24772 3200

Fig. 6. Designated place for all trolleys and stackers in the pre-weighing area.

Fig. 7. Floor marked as per the filling size packing.

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Fig. 8. Area marked for filled pallets.

Fig. 9. Tool box fixed nearby work centers.

Fig. 10. Raw material reorganized in the store.

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

63

Fig. 11. Different types of trash bins (from left to right: Packing material, plastic waste, and jumbo and paper bags).

Fig. 12. Monthly waste disposal in 2017.

5.2. The Results Obtained Using Single Minute Exchange of Dies (SMED) Filling of small Stock Keeping Units (SKUs) consider as a big challenge for many reasons. Lacking of fully automatic filling line, high mix of SKUs, number of workers required, ergonomics, etc. are top reasons that affect the production plan adherence and the production of small SKUs efficiency. The plan to implement the SMED concept was decided to take place on a filling line that is designed to fill three packing

sizes, which are 16.2 (large), 3.6 (medium) and 0.9 (small) liters respectively. The first step to apply SMED is to sort out the internal process and external processes. The internal process is a process or task that it can be performed only when the machine is off, while external tasks can be performed even when the machine or process is running. The idea is to convert the internal process into external process. The main area of improvement was to fabricate and design the

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parts and adjustment in a way that more efficient and with less cycle of time, the maintenance team has suggested some points of improvement as follows:  Lid closer unit was standardized as some modification done to the holder in a way that only one holder can fit all types of lid closer.  Marking for the level of weight was defined to adjust easily from SKU to another (Drums to gallons or small packs to drum).  The conveyor was adjusted in a way that it can hold all the three sizes of packs with only small adjustment of the safety guard. Tables 2 and 3, describe the changeover cycle time between all packing sizes before and after the implementation of SMED. Table 2. Changeover cycle time before implementing SMED.

Before Time (Min.) Packing size Large Medium Small Large 0 20 30 Medium 30 0 15 Small 22 17 0 Table 3. Changeover cycle time after implementing SMED.

After Time (Min.) Packing size Large Medium Small Large 0 7 Medium 6 0 Small 5 4

9 4 0

The overall time for performing the changeover task from the large size to the small packing before the improvement was 22 minutes while it was reduced after the improvement took place to reach only to 5 minutes. However, the workers could not sustain changeover time of 5 minutes, after seven weeks they have successfully sustained at 9 minutes’ changeover. Figure 13, shows the changeover cycle time between different

packing sizes when implementing SMED process over seven weeks. 5.3. The Results Obtained Using Work Standardization One of the reasons of low productivity is the high number of defected output. So, Pareto analysis implemented in the charging process to understand the causes for rejecting the batches by laboratory. Root cause analysis data for the full month gathered and analyzed for better understanding. The team stated below points as the main factors that cause the batch rejection during charging process:  Operators skills/mistakes  Wrong pre-weighing  Programmable logic controller (PLC) error  Wrong raw material label  Others Operators’ skills/mistakes reflect any task performed by them but in a wrong manner or not as per the given instructions (e.g. mixing time, wrong addition, dissolver speed, etc.). Wrong pre-weighing means that the pre-weighing operators give wrong raw material batch or there is deviation in the raw materials given (i.e. wrong weighing of row material or not accurate weight). System's error is a reason that causes the rejection of the batch through wrong addition of raw materials, which are added through PLC system i.e. automatic addition of bulk raw materials through system and pipelines. Wrong raw material labels mean that the raw material store have pasted wrong label for a specific raw material. Others reflect any other reason that causes the defect of the batch under process such as dissolver breakdown during mixing process or any complex process. Out of 330 batches produced in a month there were 20 batches rejected by laboratory due to different reasons (see Table 4). Pareto chart, given in Fig. 14, indicates that more than 70% of defected batches were because of the operator’s skills during the charging process.

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An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

Table 4. Status of defected batches before applying work standardization technique. Before applying work standardization Defects Charging process (in batches)

Defects (%)

Operator mistake

14

70%

Wrong pre-weighing

2

10%

PLC/System error

1

5%

Wrong label for RM

1

5%

Others

2

10%

20

100%

A month after the training session was finished, it showed that the number of defected batches caused due to operator’s skills/mistakes

reduced to reach only six batches out of 322 batches. (Table 5 and Fig. 15). Table 5. Status of defected batches after applying work standardization technique. After applying work standardization Defects Charging process (in batches)

Defects (%)

Operator mistake

6

43%

Wrong pre-weighing

2

14%

PLC/System error

1

7%

Wrong label for RM

2

14%

Others

3

21%

14

100%

Fig. 13. Cycle time for changeover between different packing sizes.

Fig. 14. current Pareto chart for the charging process defects.

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Fig. 15. Pareto chart for the charging process defects after work standardization.

5.4 The Results Obtained using KANBAN Technique In paint manufacturing, there are fast moving and slow moving liquid paint products. In the paint company under study, the liquid paint product, say product (A) is defined as fast moving product, which is contributed by 55% of the total production annually. This type of products uses several raw materials for manufacturing. The raw materials used to manufacture the product (A) can be categorized as raw material that is coming from supplier directly and can be used as it is or as raw material that is produced in the factory as a semi-finish product to be used for the manufacturing this product (A). The semi-finish product is stored in Intermediate Bulk Containers (IBCs), a big PVC tank having a capacity of 1000 Liter. The production efficiency is monitored by the production engineers and coordinators. However, the reports show that raw material shortages are a bottleneck in the production department therefore, the team has investigated

the reasons behind the shortages and it was found that migration of raw material and fluctuation of the lead-time from suppliers is the most causes of the shortages of the raw material. In fact, the engineers have found that shortages of semi-finish product have a big contribution in the total shortages occurred during the year. Further investigation concludes that the shortages of the semi-finish raw material is not because of the unpredicted increase of the lead time, neither the delay from the custom nor from the inspections but it was because of lack of controlling of the stock of the semi-finish product. The raw material staff are busy with the raw material follow up and has no clue with the semi-finish raw material. The production team is not familiar of controlling of stock of raw material and thus leading to shortages of such semi-finish raw material. A brain storming session conducted with the production operators, supervisors, raw material storekeeper and engineers to find best possible solution that can eliminate the sudden shortages of the semi-finish raw material. Applying production Kanban will have the

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

potentials to better control the stock of the semi-finished raw material, the team concluded. To do this, production engineers calculated the number of Kanban that ensures no shortage would occur. The idea is to make it visible and easily understand by the shop floor operators. Two lean techniques were used to help in this matter, Production Kanban and work standardization. Here, production Kanban will be handled. The team used the equation shown below to determine the number of Kanban required to insure there will be no stoppage of production due to yellow oxide shortage.

Where demand during lead time = consumption per day multiply by lead time to replenish an order. Due to the high uncertainty for this item, the safety stock decided to be 20% of the demand during the lead-time. One IBC (container) can take up to 500 Liter of yellow oxide. The daily average consumption of Yellow oxide is 370 Liters and the lead-time to produce an order of yellow oxide is 6 working days. The calculations show that 5.77≃6 containers/Kanban (500*6 = 3000 Liters batch) will be the ideal number of Kanban’s/Containers. Since the production, process of yellow oxide is complex and it takes one full day of production. Yellow oxide is produced on the same dissolver that used to manufacture many different products that required by customers (Finish goods products). The engineers decide to make a signal Kanban systems that can store up to 6 containers (i.e. pallets). The Kanban area is consisting of 6 pallets. One container will be placed in the manufacturing floor, where it pre-weighted by the manufacturing operators to produce another

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product. Once the container is fully consumed, the manufacturing operator will inform the forklift operator to bring a new container from the Kanban area. The forklift operator will go to the Kanban area and will take one container and place it in the manufacturing floor. This process will be repeated until there remains only one container in the Kanban. Once the forklift goes to bring the 5th container, he will see a signal in the Kanban area (painted in red) that will indicate to the production planner to place an order for the yellow oxide. Six days is the time required to refill the Kanban area with full 6 containers with a batch size of 3000 liters and it’s the average consumption rate for the remaining container, i.e. the last container that remains for use will be sufficient to run the production for 6 days, which is the lead time to manufacture the yellow oxide and re fill the Kanban fully. As mentioned earlier, one of the bottlenecks in the pre-weighing process is the number of the pre-weighed batches, which will affect the charging process if the next pre-weighed batch is not ready. Product (A) which is 55% of total Jeddah factory output is being produced in 5 different production lines which are dedicated for this product. Any delay in the pre-weighing process will affect the charging efficiency and thus can delay the manufacturing process and accordingly the customer demand. The root cause behind the delay of the pre-weighing process is the sudden order of the next pre-weighed batch from the charging operator where the shop order is still not yet submitted to the pre-weighing operator or because there is an urgent order from a customer and the shop order is still not yet handled to the pre-weighing store. There are three standard batch sizes for five different production lines. Table 6, illustrates each production line batch size.

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Table 6. The different batch sizes according to the production line.

As described in the table above, there is only 3 different sizes of pre-weighing batches. Production lines 1 and 2 have the same batch size and thus the pre-weighing materials are the same for both tanks (i.e. the weight of the raw material for both production lines is the same and it can be used also for production line two as the product is one and the size is the same). The same concept is for production line four and five. The team has decided to make a super market Kanban for this product aligned for the 5 production lines. Racks has been installed and divided into three columns, where each column allocated to standard batch size, which are 4400, 6650 and 8022 liters. The idea is to let the pre-weighing operators fill the Kanban with no shop orders attached. This super market Kanban will make sure that the pre-weighed batches are always available to start the charging process. The shop order papers will be with the charging operators instead of being handed to the pre-weighing operators (Fig. 16). Currently the number of pre-weighed batches for is equal to 19 batches per shift and after the implementation of the super market Kanban the pre-weighing operator were able to pre-weigh total of 30 batches where the waiting time has been reduced to reach only 2 minutes. Production stoppage due to pre-weighing process was reduced to reach only 3 times for a full month and the process mapping for the preweighing stage further improved to be as described in Fig. 17. 6. Discusstion Applying lean principles and tools in manufacturing facilities is a quick win strategy especially if it is newly applied (i.e. first time for application in a certain company). As a conclusion, the suggested four Lean

Manufacturing (LM) tools applied throughout the manufacturing process made significant difference. These four tools named: 5S, SMED, work standardization and Kanban achieved the study objectives. The study dealt with the three main processes in paint manufacturing which are pre-weighing process, charging process and filling process. The four LM techniques implemented in all the three processes simultaneously.

Fig. 16. Super market Kanban.

Pre-Weighing Process Since the pre-weighing process is the first step in the real painting manufacturing process and thus, any improvement in this stage will directly improve the next processes that are charging and the filling process. Supermarket Kanban and 5S techniques have significantly improved the pre-weighing process. Organizing the workplace (5S) through creating dedicated (marked) areas for the weighing scales, trolleys, stackers, RM, etc. reduced the average pre-weighing time of a single batch by 36% (i.e., from 25 minutes to 16 minutes). The supermarket Kanban played a massive rule in increasing the productivity. The pre-weighing process daily output increased by 57% and reached to 30 batches instead of 19 batches daily. Below points illustrate the improvement clearly:  Pre-weighing Cycle time per batch: 16 min

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

 Number of batches pre-weighed per shift: 30 batches  Total waiting time (non-value added): 2 min  Total Movement time (non-value added): 3 min  Total non-value added time: 5 min  Total value added time: 11 min

Charging Process The 5S or workplace organization technique improved the process efficiency and reduced the time of the tasks involved in the production process. The main contribution in the charging process attained by the implementation of work standardization and the Pareto chart where the number of the defected batches due to operators’ mistake has been reduced from 14 to 6 that means reduction by 57%. Starting the pre-weighing process with supermarket Kanban for the fastest moving products increased the productivity of the charging process as the operators will not wait for the pre-weighing next batch due to delay from the planner or the workload. The average charging time for the fastest moving products was 150 minutes and after the implementation of 5s and the Kanban system, it has been reduced to 122 minutes (i.e., saving time by 19%).

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Filling Process Applying 5S Technique in the filling area decreased the movement of the operators to remove the pallets and thus, it reduced the average filling time. In fact, the cleaning of the machines and filling lines including the conveyors during the preventive maintenance are improved and the down time is reduced significantly. In addition, SMED technique has increased the adherence to the daily production plan. Adherence to the daily production plan is calculated by activity (i.e. the planners will assign for each work centers a target that is based on the product and the time associated for manufacturing so if the production team completes the target for all the work centers they can get 100% adherence to the plan). Figure 18 shows the adherence to the daily production plan for Nov. 2017 after implementing SMED and 5S techniques. Waste Management Using 5s technique to control the waste handling and treatment reduced the cost more than expected. In fact, the non-hazardous waste and the hazardous waste have been reduced by 85% and 53% respectively (Fig. 19).

Fig. 17. Improved process mapping for the pre-weighing process.

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Fig. 18. Production plan adherence.

Fig. 19. Waste disposal before and after the 5s technique.

The implementation occurred only in Dec.2017 to test the impact and it proves that the impact was significant. The overtime associated for each month has been reduced as a result of implementing the LM techniques (Fig. 20). 7. Conclusion Understanding the manufacturing process deeply is a vital to track the bottlenecks and then the area of improvements. Lean manufacturing principles proofs its ability to increase the productivity without the need to spend much

money as its more of administrative tools and solutions. Being able to control and minimize the waste using a technique like 5s, which not required big budget to implement, is a key solution during recession. The benefit of techniques like fishbone analysis, SMED, value stream mapping, etc. not only in increasing the productivity and identifying the area of weakness, in fact, theses techniques will enhance the team work and will increase the engagement level of the people which itself will motivate them and give them a space to innovate.

An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study

Meeting the customer expectations during recession is important and will insure more market share, where many rivals will suffer in meeting the customers' demands if not responding quickly and effectively and lean manufacturing principles have all the abilities to do so. 8. Future Work This study has proven that applying the Lean Manufacturing (LM) principles is a key success factor in achieving high productivity rates and overcomes the productions bottlenecks. However, there are some recommendations and suggestions that if

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applied will further enhance the productivity and identify more bottlenecks. Applying 7s, which is the developed technique of 5s, will enhance further the impact of the technique. Including the laboratory stage will further increase the productivity and reduce the lead time. Future status of VSM will could better point out the improved area. As human, the tendency to resist any new change is natural and therefore it should be tracked properly prior implementing any new technique or procedure by introducing the change to the people and letting them understand the change before acting it.

Fig. 20. Overtime trend while implementing LM tools. References

[5]

[1] Tortorella, G. and Fogliatto, F., Implementation of lean manufacturing and situational leadership styles: An empirical study, Leadership & Organization Development Journal, 38 (7): 946-968 (2017).

Puvanasvaran, A. P., Managing waste elimination database in Lean manufacturing: Improve problem solving capability, American Journal of Engineering and Applied Sciences, 7 (2): 271-281 (2014).

[6]

Wilson, L., How to Implement Lean Manufacturing, McGraw-Hill Education, 1st edition, US, NY, PP 73128 (2015).

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Ab Rahman, M. N., Khamis, N. K., Zain, R. M., Deros, B. M. and Mahmood, W. H. W., Implementation of 5S practices in the manufacturing companies: A case study. American Journal of Applied Sciences, 7(8): 1182-1189 (2010).

[8]

Ghodrati, A. and Zulkifli, N., The Impact of 5S

[2]

Krafcik, J. F., Triumph of the lean production system. Sloan Management Review, 30(1): 41–52 (1988).

[3]

Wang, J. X., Lean Manufacturing: Business bottomline based. Boca Raton, CRC Press, 1st edition, Florida, Boca Raton (2011).

[4]

Bhasin, S., Lean management beyond manufacturing: A holistic approach. Springer-Cham (Switzerland), pp: 149-160 (2015).

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Implementation on Industrial Organizations’ Performance. International Journal of Business and Management Invention, 2(3), 43-49 (2013). [9]

Sajan M.P., Shalij P.R., Ramesh A. and Biju Augustine P., Lean manufacturing practices in Indian manufacturing SMEs and their effect on sustainability performance, Journal of Manufacturing Technology Management, 28 (6) : 772-793 (2017).

[10] Sabadka, D,. Molnar, V. and Fedorko, G., The use of lean manufacturing techniques - SMED analysis - to optimization of the production process, Advances in Science and Technology Research Journal, 11 (3): 187– 195 (2017). [11] Madhav, R., Marnewick, A., Nel, H. and Pretorius, J. H., Managing Changeover Waste in Manufacturing Plants when Using Single Minute Exchange of Dies, IEOM Society International, Morocco April (2016). [12] Bajpai, J. D., SMED (single-minute exchange of die) methodology in garment manufacturing industry: Case study in reducing style change over time. In

Proceedings of the 5th International & 26th All India Manufacturing Technology, Design and Research Conference (AIMTDR 2014), Guwahati, India, pp: 1214) (2014). [13] Lucherini, F. and Rapaccini, M., Exploring the Impact of Lean Manufacturing on Flexibility in SMEs, Journal of Industrial Engineering and Management, 10(5): 919945 (2017). [14] Dennis, P., Lean Production simplified: A Plainlanguage Guide to the World's Most Powerful Production System, Productivity Press, 3rd Edition, pp:102-110 (2015). [15] Corona, E. and Pani, F. E., A review of lean-kanban approaches in the software development. WSEAS Transactions on Information Science and Applications, 10(1): 1-13 (2013). [16] Reddy, A. (2015). The Scrumban [r] evolution: Getting the Most Out of Agile, Scrum, and Lean Kanban. Pearson Education, US, Indiana (2015).

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‫‪An Application of Lean Manufacturing Techniques in Paint Manufacturing Company: A Case Study‬‬

‫نيع الخالي من الهدر فى شركة لتصنيع الدهان‪ :‬حالة دراسية‬ ‫أحمد باديب‪ ،‬و رضا عبد العال‪ ،‬و عبد اهلل بافيل‬ ‫قسم الهندسة الصناعية‪ ،‬كلية الهندسة‪ ،‬جامعة الملك عبد العزيز‪ ،‬جدة‪ ،‬المملكة العربية السعودية‬ ‫المستخلص‪ .‬نتيجة لالنكماش االقتصادي الحاصل في المملكة العربية السعودية‪ ،‬بدأت شركات التصنيع بالتفكير في تقليل التكلفة‬ ‫التشغيلية وزيادة اإلنتاجية‪ ،‬وذلك باستخدام نظريات التصنيع الخالي من الهدر‪ .‬وعليه‪ ،‬فإن هذه الورقة تهدف إلى دراسة عملية‬ ‫التصنيع في قطاع إنتاج الدهانات‪ ،‬ومن ثم تحديد المناطق التي تؤثر بشكل سلبي على العملية التصنيعية‪ ،‬وذلك باستخدام طرق‬

‫تحليليه تساعد على اكتشاف تلك المناطق‪ .‬وبناء على تلك الدراسة‪ ،‬تم اختيار بعض أساليب التصنيع الخالي من الهدر التي من‬ ‫شأنها تقليل الهدر في العملية التصنيعية وزيادة اإلنتاجية‪ .‬تمت دراسة عملية تصنيع الدهانات بشكل تفصيلي ساهم في تحديد‬

‫مناطق الهدر‪ ،‬وعليه فقد تم اختيار طريقة "تنظيم منطقة العمل" و" تحسين وقت تغيير إعدادات اآللة" حيث ساهمت الطريقتان في‬ ‫زيادة اإلنتاجية اليومية‪ ،‬وتم تقليل وقت التغيير بنسبة وصلت إلى ‪ .٪ 59‬إضافة إلى ذلك تم تطبيق طريقة "توحيد طرق التشغيل"‬ ‫كإحدى أساليب التصنيع الخالى من الهدر‪ ،‬وقد ساهم ذلك في تقليل نسبة الدفعات التشغيلية المرفوضة بنسبة ‪ .٪ 57‬كما ساهمت‬ ‫الطرق الحديثة في التحكم ومراقبة المخزون واإلنتاج في الحد من التوقف المفاجئ للعملية التصنيعية بسبب نفاد المواد الخام بشكل‬

‫كبير‪ ،‬مما ساهم في زيادة إنتاجية المصنع‪ ،‬وتحقيق أهداف الورقة العلمية‪ .‬إضافة إلى ذلك‪ ،‬فقد تم تقليل تكلفة معالجة المخلفات‬ ‫الصناعية الخطرة وغير الخطرة‪ ،‬والناتجة من عمليات التصنيع‪ ،‬بنسبة بلغت ‪ ٪ 53‬و ‪ ٪ 85‬تواليا‪ ،‬وذلك عن طريق تطبيق‬ ‫أسلوب "تنظيم منطقة العمل"‪.‬‬ ‫كلمات مفتاحية‪ :‬تصنيع الطالء‪ ،‬التصنيع الخالي من الهدر‪ ،‬دقيقة واحدة لتبادل القوالب‪ ،‬تقنية تنظيم مكان العمل‪ ،‬تحسين وقت‬ ‫تغيير إعدادات اآللة‪.‬‬

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