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151.
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   
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153.
This paper describes a group of techniques for disaggregating origin–destination tables for travel forecasting that makes explicit use of observed traffic on a network. Five models within the group are presented, each of which uses nonlinear least-squares estimation to obtain row and column factors for splitting trip totals from and to larger geographical areas into smaller ones. The techniques are philosophically similar to Fratar factoring, although the solution method is quite different. The techniques are tested on a full-sized network for Northfield, MN and are found to work effectively.  相似文献   
154.
State agencies responsible for ADA-eligible paratransit services are increasingly under pressure to contain costs and maximize service quality. Many do not operate vehicles themselves; instead, they contract out the provision of services. Contractors are paid for each hour of service. They are responsible for hiring crew, forming routes, dispatching, and operating and maintaining agency-owned vehicles. In the Twin Cities of Minneapolis and Saint Paul, Metro Mobility, the agency responsible for providing paratransit services, requires contractors to use agency-approved software for booking trips dynamically and sets parameters that guide contractors’ practices. Customer trips booked in this fashion may not utilize capacity in the most efficient manner. Therefore, beginning with the daily trip schedules generated by the software, this paper proposes two approaches for improving the efficiency of paratransit operations and estimates the benefit of using these approaches via experiments that utilize Metro Mobility data. The first approach re-optimizes routes developed at the end of each day. The second approach evaluates the benefit to state agencies of selectively using non-dedicated service providers such as taxis. Both approaches are tested on actual data obtained from Metro Mobility. The study shows that a conservative estimate of savings from re-optimization would be approximately 5% of Metro Mobility’s operating costs. Savings from the use of taxis are smaller and in the range of hundreds of dollars per day.  相似文献   
155.
This paper presents the first route choice model for bicyclists estimated from a large sample of GPS observations and overcomes the limitations inherent in the generally employed stated preference approach. It employs an improved mode detection algorithm for GPS post-processing to determine trips made by bicycle, which are map matched to an enriched street network. The alternatives are generated as a random sample from an exhaustive, but constrained search. Accounting for the similarity between the alternatives with the path-size factor the MNL estimates show that the elasticity with regards to trip length is nearly four times larger than that with respect to the share of bike paths. The elasticity with respect to the product of length and maximum gradient of the route is small. No other variable describing the routes had an impact. The heterogeneity of the cyclists is captured through interaction terms formulated on their average behaviour.  相似文献   
156.
This study assesses the effects of aircraft noise on residential satisfaction, an important indicator of subjective well-being. A structural equation model is specified that estimates the relationships between objective variables, noise annoyance variables and residential satisfaction. Secondary data-analysis is used to estimate the model. The survey was conducted in 1996/1997 among the population living within a 25-km radius of Amsterdam Schiphol, the largest airport in the Netherlands. The effect of aircraft noise annoyance is found to be relatively small. In addition, the objective level of aircraft noise exposure is found to be a better predictor of residential satisfaction than its subjective counterpart. The most important determinants of residential satisfaction are found to be road traffic noise annoyance, age and neighbor noise annoyance.  相似文献   
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158.
Hybrid vehicles of different configurations and utilizing different energy storage systems have existed in development for many decades and more recently in limited production. They can be grouped as parallel, series or complex hybrids. Another classification is micro, mild and full hybrids which makes the distinction on the basis of functionality. The common energy storage systems in hybrid vehicles are batteries, supercapacitors and high speed flywheels. This paper aims to review a specific type of hybrid vehicle which involves the internal combustion engine (ICE) as the prime mover and the high speed flywheel as an energy storage device. Such hybrids are now attracting considerable interest given their potential for low cost. It is hence timely to produce a review of research and development in this subject. The flywheel is coupled to the drive line with a continuous variable transmission (CVT). The CVT can be of various types such as electrical, hydraulic or mechanical but usually in this case it is a non-electrical one. Different configurations are possible and the paper provides a timeline of the development of such powertrains with various examples. These types of hybrid vehicles have existed as prototypes for many decades and the authors believe that their development has reached levels where they can be considered serious contenders for production vehicles.  相似文献   
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160.
Finite element modeling of static tire enveloping characteristics   总被引:1,自引:0,他引:1  
To investigate static tire enveloping characteristics, a three dimensional (3-D) finite element model is proposed. The vertical stiffness of the tire is studied on a flat surface with and without cleat. Tire rubber materials and cord layers are represented independently using “rebar” elements available in MSC Marc Mentat. Comparisons of numerical and experimental results are given to show the validity of the proposed model. It is shown that after a certain displacement, the results of the proposed model agree well with experimental results. In addition, the model results show that regardless of the type of the cleat placed under the rim center (hub center), all vertical force curves intersect after a certain displacement, which indicates typical static enveloping characteristics. Moreover, another typical characteristic of the radial tires that is unlike those of bias-ply constructions confirms that the contact patch does not expand laterally after a level vertical load is applied to the tire, which is directly related to fuel consumption and tire tread life.  相似文献   
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