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21.
In this paper, reasonable paths in transit networks are defined as possible paths that satisfy the acceptable time criterion and transfer‐walk criterion. A recursive algorithm for finding all of the reasonable paths in a transit network that does not involve a rapid increase in program run‐time with network size is presented. Realistic transit networks in Hong Kong and Guangzhou were selected as case studies of the different phases of the development of a trip planning system. Transport planning practitioners and potential users were invited to test the system to evaluate its performance. The results of the prototype evaluation were satisfactory, and the viability of the system as a useful tool for supporting decision‐making has been confirmed by the positive feedback that was obtained from survey questionnaires.  相似文献   
22.
Road roughness and surface texture are known to affect tire rolling resistance; however, little emphasis has been placed on the consequent changes in total vehicle energy dissipation due to road roughness. Thus, tire rolling resistance, in isolation from vehicle contributed losses such as dissipation in the suspension, appears to be a weakness in present evaluation procedures as they relate to fuel economy and pollution level testing: Recent work by Funfsinn and Korst has shown that substantial and measurable increases in energy losses occur for vehicles traveling on rough roads. The present investigation uses vehicle axle accelerations as a means of examining various road surfaces. Correlation with computer simulations has allowed the development of a deterministic road roughness model which permits the prediction of energy dissipation in both the tire and suspension as functions of road roughness, tire pressure, and vehicle speed. Comparison to the experiments of Korst and Funfsinn results in good agreement and shows that total rolling loss increases of up to 20 percent compared to ideal smooth roads are possible. The aerodynamic drag coefficient is also found to increase while driving on rough roads.  相似文献   
23.
Authenticated Diffie-Hellman key agreement is quite popular for establishing secure session keys. As resource-limited mobile devices arc becoming more popular and security threats are increasing, it is desirable to reduce computational load for these resource-limited devices while still preserving its strong security and convenience for users. In this paper, we propose a new smart-card-based user authenticated key agreement scheme which allows users to memorize passwords, reduces users' device computational load while still preserves its strong security. The proposed scheme effectively improves the computational load of modular exponentiations by 50%, and the security is formally proved.  相似文献   
24.
Under certain assumptions, values of travel time (VOT) can be divided into two parts: one associated with travel (i.e., the value of reducing travel time disutility) and the other associated with activities (the shadow price of time). The empirical results of combining RP and SP data showed that the VOT of travel was greater than that of activity. The results also showed that SP experiments that did not take or only took part of activities into consideration would underestimate VOT.  相似文献   
25.
This paper discusses negotiations, relative to sea fisheries, in terms of international arrangements—arrangements between the European Economic Community (EEC) and Third Countries; and those between member states of the EEC.  相似文献   
26.
Abstract

In southern Rhode Island, there is growing concern that housing and recreational demands will soon overwhelm the capacity of the coastal salt ponds to absorb wastes, produce seafood, and maintain scenic qualities. As a result, coastal towns have been studying the feasibility of using land controls such as downzoning to protect these coastal amenities. The paper presents an economic analysis of the downzoning program proposed in the town of South Kingstown. Hedonic price and contingent valuation methods are used to value coastal amenities. The estimated net present value of “swimmable” water is shown to be $3.1 million.  相似文献   
27.
This paper starts by reviewing the main components of social marginal costs and environmental costs in the context of transport, and it draws on the experience in Europe concerning the means by which these costs can be valued. That experience is then translated to the situation in Lithuania, where many of the same issues are now being debated. A multicriteria method is proposed to internalize these costs, both from the perspective of the state and of the carriers. Costs need to be raised substantially if the social and environmental factors are to be paid for by the transport users, and such action would bring Lithuania closer to the best practice currently in operation in the European Union.  相似文献   
28.
29.
Based on the multi-spoke, single-plane, steady-state tyre model, a transient multi-spoke, three-plane tyre model is presented. This model involves updating the states of all the spokes under consideration to t+dt from the corresponding states at t. Also, a spoke base, which has lateral and longitudinal flexibilities relative to wheel hub, is included. By adding two extra planes of spokes to the original one, the effect of tyre width is built into the model. The three planes are equally spaced across the width of the tyre. The interaction with the ground of the spokes on these three planes is used to represent that of tyre elements at different locations across the width. Analytical results show good qualitative agreement with published experimental data. This model can be used to illustrate transient tyre behaviour and in simulations in which a generic tyre will suffice.  相似文献   
30.
Santa Clara County, California experienced a sharp growth in demand‐responsive paratransit ridership for individuals with disabilities, as a result of the passage of the 1990 Americans With Disabilities Act (ADA). This paper describes an automated paratransit system for the ADA‐type paratransit operation implemented in Santa Clara County. It automated paratransit reservation, scheduling, and routing functions. The key components of this system were a digital geographic database (DGD) and an automated trip scheduling system (ATSS). Empirical evidence after one year of operation indicates numerous benefits of this automation. There were significant reductions in the paratransit operating costs and an increase in the percent shared rides. The savings in operating costs far exceeded the annualized capital cost of automation. A user survey indicates that these improvements were achieved without degradation to service quality such as vehicle on‐time performance, invehicle travel times, vehicle response to open return, and ride comfort.  相似文献   
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