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81.
Fuel consumption is calculated using a modelling procedure for automobiles travelling on three alternative street patterns designed for a subdivision in Kingston Township, Ontario. The modelling procedure is described. The results indicate that grid and solar superblock street patterns, compared to the existing street pattern, offer small fuel savings to a tripmaker in the portion of the work trip travelled in the subdivision. 相似文献
82.
David I. A. Steel 《Maritime Policy and Management》2013,40(6):425-430
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
83.
84.
Newell Garfield Mathew E. Maltrud Curtis A. Collins Thomas A. Rago Robert G. Paquette 《Journal of Marine Systems》2001,29(1-4)
During the period 1992–1998, 38 isobaric RAFOS floats were deployed to sample the subsurface flow of the California Undercurrent. The deployments, released over the California continental slope west of San Francisco, have sampled robust year-round poleward subsurface flow associated with the Undercurrent most seasons and the combined inshore current and Undercurrent in winter. Two other types of flow have been seen: a region of weak flow with little net displacement just west of the California Undercurrent, and an active westward propagating eddy field. This eddy field appears to be the primary mechanism for moving floats from the Undercurrent into the ocean interior. The observations and statistics from the RAFOS floats are compared with Lagrangian estimates of particles tracked in a global high resolution ocean simulation in order to evaluate the fidelity of the model along an eastern boundary. The results show that the model reproduces the general character of the flow reasonably well, but underestimates both the mean and eddy energies by a substantial amount. 相似文献
85.
Diwakar Gupta Hao-Wei Chen Lisa A. Miller Fajarrani Surya 《Transportation Research Part A: Policy and Practice》2010,44(4):201-217
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
86.
Maarten Kroesen Eric J.E. Molin Henk M.E. Miedema Henk Vos Sabine A. Janssen Bert van Wee 《Transportation Research Part D: Transport and Environment》2010,15(3):144-153
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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88.
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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