EMPA Activities 2002 Information, Simulation Technologies, Reliability
Lorenz Hilty, Frank Hartmann, Thomas Ruddy, in collaboration with Sigfried Behrendt, IZT (D)
Impacts of new information and communication technologies to the environment The main part of the impact that the spreading of Information and Communication Technology (ICT) has on the environment is due to the life cycle of its hardware and its potential to influence traffic. Two projects in the framework of the “Sustainability in the Information Society” (SIS) program at Empa have assessed the environmental impacts of ICT for scenarios covering these two fields with a focus on “Pervasive Computing” and “Dynamic Vehicle Routing”, respectively. As a third activity, the SIS program has initiated a Network of Excellence for “Environmental Informatics” within the 6th Framework Program of the EU.
ment. It was found that potential environmental problems of pervasive computing are connected to energy demand and electronics waste. The amount of ewaste is expected to be increased by the fact that the largest part of electronic components on the market is so light and small that they fall below the threshold at which separate treatment is efficient. On the other hand, there are developments in the ICT sector that affect material flows in ecologically favorable ways. As Fig. 1 shows, it is to be expected that the mass flow caused by purchases of monitors in Switzerland will decrease because LCD monitors are much lighter than CRT monitors. Besides that, they contain less toxic substances than CRT monitors, and thus cause fewer disposal problems.
The technological and market trends are leading to a new type of ICT, pervasive computing, made possible by the ongoing miniaturization of digital electronics. Pervasive computing is understood as the provision of data processing, storage and wireless communication capacity in a variety of stationary or mobile objects, as well as on or in the human body. Manufacturers expect in their pervasive computing scenarios that around 1000 electronic components will be used per person. On contract from the Swiss Center for Technology Assessment (TA Swiss), Empa assessed the advantages and risks of pervasive computing for health and the environ-
Positive environmental impacts of ICT can be achieved in the transport sector. Telecommunications has increasing importance in fleet management. Mobile data communications in combination with a GPS (Global Positioning System) or cheaper location determination technologies based on a mobile telephone network such as TDOA (Time Difference of Arrival) or E-OTD (Enhanced Observed Time Difference) make it possible to exactly determine the location of a company vehicle at any time. Thus, all information is available that is necessary to react optimally to short notice perturbations, such as additional orders or traffic disturbances. In cooperation
4 500 total mass CRT monitors LCD monitors (desktop) LCD monitors (notebook)
4 000 3 500
Mass flow in tons
3 000 2 500 2 000 1 500 1 000 50 0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Years
Fig. 1: Forecast of mass flow caused by sale of computer monitors in Switzerland.
70
EMPA Activities 2002 Information, Simulation Technologies, Reliability
6000 5800 Strategy 1
5600
Strategy 2
5400 Distance [km]
with Circon AG and three universities of applied sciences (Solothurn, Basel, Luzern), Empa developed and validated a stochastic simulation model in the domain of dynamic vehicle routing. Given the fact that it is necessary to go from a static to a dynamic method of vehicle route planning in order to make use of the available information, a company must ask how to deal with orders coming in on short notice and what consequences different strategies to handle these orders have on the length of distances driven and the utilization of trucks. Two basic strategies are:
5200 5000 4800 4600 4400 4200 4000 0
• Strategy 1: Short-notice orders are integrated into running routes optimally as regards time and costs, as they come in. Orders that have already been planned are not changed. • Strategy 2: This strategy combines into a new route each short-notice order with those that have not yet been taken care of, although they have been already planned with the aid of the “Cheapest Insertion” algorithm. Thus, routes that were planned and optimized are destroyed. Our simulation model is able to assess the performance of such strategies using a sample of the data from the trucking company under study. All constraints relevant in practice are represented as parameters such as the weight and volume capacity limits of vehicles, drivers’ working times, distribution of order attributes etc. Another parameter makes it possible to vary hypothetically (0 –100%) the percentage of orders considered “dynamic”, i.e. the ones that have to be integrated into truck routes that are already proceeding. In this way, the relative performance of different strategies to solve a variation of the Dynamic Vehicle Routing Problem (DVRP) can be simulated under the assumption of different dynamic shares. Important output variables include the sum of distances driven, the associated costs for the company and the environmental impact. Our model was validated using a Swiss trucking company as an example. Fig. 2 shows how the performance of optimization strategies, indicated in this example by the total distance covered, can be compared on different levels of the dynamic share. The model uses the detailed geographic distribution of the customers and other specific data of the
10
20
30
40
50
60
70
80
90
100
Dynamic share [%]
Fig. 2: Comparison of total distance driven for two optimization strategies and different dynamic shares.
trucking company for which it is applied. The insights gained in simulation experiments can lead to considerable savings in traffic load and energy use. Applications of ICT to monitor, analyse and reduce environmental load like the one described above are treated systematically in the discipline of Environmental Informatics. Empa has now initiated a Network of Excellence on Environmental Informatics within the 6th Framework Program of Research and Technological Development of the European Commission. Among the partners are the European Environment Agency (EEA) and the United Nations Environment Program (UNEP). The aim of the network is to stimulate convergence of activities towards: (i) standards for environmental data in space and time, (ii) user-friendly and multilingual tools and services, (iii) deriving knowledge from heterogeneous sources in a reproducible way, (iv) bridging the gap between environmental data and decisions to be taken in: natural resource management, risk prevention, crisis management, and resource-use efficiency.
Support: BBT-KTI 4980.1, Circon AG, TA Swiss Links: www.empa.ch/sit
Contact:
[email protected] References: F. Hartmann, et al., Computers & Industrial Engineering, submitted (2002)
71
