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991.
Various alternative frameworks are available for modelling urban land‐use–transport interaction. This paper provides a detailed review of six of these frameworks that have been or are currently being used to develop operational models. The intention is to indicate what is the general nature of the current state of practice and what is now available for practical modelling work in the area. The intention is also to compare the current state of practice with what might be the ideal in various respects. The six frameworks reviewed (ITLUP, MEPLAN, TRANUS, MUSSA, NYMTC‐LUM and UrbanSim) are considered in terms of their representations of physical systems, decision‐makers and processes, along with various more general modelling and implementation issues. None matches the ideal as envisaged here in all respects. However, a wide range of policy considerations can be handled explicitly with what is available, and more recent developments show an encouraging trend towards expansion in the scope of what can be considered. Further strengthening of the behavioural basis and relaxation of some of the more restrictive assumptions would appear to be both appropriate and likely in the future. 相似文献
992.
Lisa-Ann Gershwin Monica De Nardi Kenneth D. Winkel Peter J. Fenner 《Coastal management》2013,41(1):22-41
Dangerous marine stingers (jellyfish) are an emotive issue in tropical Australia, where they are widely regarded as the number one marine health threat. However, numerous severe and fatal stings have been reported throughout the tropical and temperate seas of the world, indicating that marine stingers are a global health problem. Further, life-threatening jellyfish stings are more frequently reported globally now compared to earlier decades, possibly as a result of improved recognition and reporting, or increased spatial and/or temporal distribution or densities. As stinging incidents may also have significant financial implications (lost tourism revenues and liability settlements), and the treatment of envenomed patients comes at high cost to the taxpayer, this issue is also a management challenge. This article outlines suggested approaches, based largely on Australian experience, for dealing with this under-recognized global coastal management issue. 相似文献
993.
Transit service contracting has responded to fiscal and financial woes of public transit agencies as the most uniquely attractive cost‐saving strategy at present. Most transit service contracting, however, has been in the traditional provision of entire fixed route bus service or commuter express bus service, and exclusive demand responsive service for the general public or for special disadvantaged population groups such as the elderly and/or the handicapped. This paper presents a new module in transit service contracting whereby the public and private operators jointly provide the peak service on the same route and at the same time. While the public agency provides the base demand of the service, the private provider provides the excess demand, both following the same schedules and similar service arrangements. In this paper, proposed service arrangements, costing and contracting procedures are discussed. It is also reported that substantial cost savings ranging from 32 to 57% with an average savings of 48% can be achieved if the excess peak hour bus transit service on highly peaked routes in public transit agencies is contracted to competing private operator(s). 相似文献
994.
Raimund K. Herz 《运输规划与技术》2013,36(4):311-328
The rediscovery of the bicycle by the public, by politicians and by professional urban transportation planners as a mode of transport which is perfectly in harmony with the goals of environmental protection, energy saving and personal fitness has stimulated this empirical study on the actual use of the bicycle by various population groups for obligatory and discretionary trip purposes. The influence on bicycle usage of such factors as age, education, car availability, residential density and town size, topography and time of year is analysed in this paper for selected population groups. For housewives from motorized households logit‐models were designed and calibrated to model their modal choice for shopping trips with special references to the bicycle. From the empirical results, the groups with the largest potentials for cycling are identified and the extent to which the potentials could be activated by specific policies is discussed. The research is based on a large sample held to be representative for the Federal Republic of Germany in 1976 and is supplemented by more recent surveys in selected German cities conducted by SOCIALDATA Munich. 相似文献
995.
THE SEVENTH AUSTRALIAN TRANSPORT RESEARCH FORUM, by K. W. Ogden. AIRLINE PLANNING: CORPORATE, FINANCIAL AND MARKETING by Nawal K. Taneja. Lexington, Mass., Lexington Books, 1982. 207 pp. (£19.50) SOLVING LOCAL GOVERNMENT PROBLEMS: PRACTICAL APPLICATIONS OF OPERATIONS RESEARCH IN CITIES AND REGIONS, by Charles E. Pinkus and Anne Dixson. George Allen and Unwin, London, 1981. (Hardback £20.00; paperback £8.95) SCIENTIFIC MANAGEMENT OF TRANSPORT SYSTEMS, edited by N. K. Jaismal. Published by North‐Holland Publishing Company (U.S. $58.50) TRANSPORTATION AND TRAFFIC ENGINEERING HANDBOOK (Second Edition), edited by W. S. Homburger, Englewood Cliffs, N.J., 1982. Prentice Hall, pp. 883. ECONOMICS OF PUBLIC TRANSPORT, by C. A. Nash. Longman, London, pp. 194. (£6.95). 相似文献
996.
Currently, the Hong Kong government imposes fare control on buses and taxi while the rail services are immune to such a control. This study examined four scenarios of fare deregulation on transit services by considering three related parties of a transit system – service providers, travelers, and society in general, with their respective objectives represented as – revenue, travel utility, and congestion. Analyzing the resultant impacts on these three parties, we found that a different regulatory environment would favor or hurt a different set of parties. There is no clear win‐win situation for all parties. Deciding a socially acceptable regulatory environment is likely to involve difficult tradeoffs among these parties. 相似文献
997.
重力式挡土墙是道路工程中使用最为广泛的支挡结构,其设计质量的好坏直接关系到工程的安全性和经济性。通过分析重力式挡土墙设计中容易混淆或容易忽略的常规问题,并对有些问题提出了一些建议。 相似文献
998.
P F Stratton D Ho Saxena . BOC Gases European Development Centre Rother Valley Way Holbrook Sheffield S RP UK. . The HOC Group Technical Centre Mountain Avenue Murray Hill New Jersey - USA 《上海交通大学学报(英文版)》2000,(1)
1ntroductionGaswimpfobe,usuallynitrOgen,mandheiumatposuresOfuPtO60barhasbousedinvacmbosfOrSendywtanditScharWshcsforbds-ofCOInNarewe1knOWUIl].More~theuseofgasq-aPPliedtOs~orsinglelayereOfCOmwtthawereheandindsvacuumorCOnwtalatmOSPherbohasboPrOpond(2l.TOathaatetheedtOCOOtheboacestruCtUrasweIIastheCOIntwIkeSechquesOboinvolvethetrareferOftheNttobeqMtoa~allydeaignedcoklchfortsl.6as~of~peinndsngmaybosoaS~the-ofbo'bds-Oha'pesstwfOr'juSb~'manwt.Unlikliquldbased~antS,gaswiiscleannO… 相似文献
999.
J. E. Dzielski J. K. Hedrick 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1984,13(6):315-337
The effects of track irregularities and wheel profile on the amount of energy dissipated in railroad freight vehicles is examined. A nonlinear computational model is used to determine the average dissipation in the vehicle suspension and the wheel/rail contact patches. This dissipation is a component of the total resistance force acting on the vehicle. Parametric results are presented showing the effects of track geometry, wheel profile, suspension design, and hunting on train resistance. Track geometry studies consider the effects of track quality and curving. The AAR 1:20 wheel profile and the Heumann wheel profile are compared under various operating conditions. Compared with the Heumann profile, the AAR 1:20 profile is shown to have lower average resistance on good quality tangent track, but higher average resistance in steady curves. A trade-off exists between the two profiles when dynamic curve entry is considered. 相似文献
1000.
This paper investigates the allocation of household individuals to out-of-home maintenance activities using the rich activity-travel diary data from the San Francisco Bay Area. Two inter-related decisions are considered in this context: (i) whether the given activity episode is performed individually (solo) or jointly, and (ii) the person who participates in the activity, if it is a solo activity. To account for the conditional nature of the solo activity person selection, a nested mixed logit modeling framework is proposed and implemented to jointly analyze person allocation for all maintenance activities performed by a household on a given day. The model is used to investigate within-household effects and between-household differences. The proposed model relaxes some important restrictions in person allocation models by accounting for various sources of correlations and relaxing the assumption of constant variance across households. The proposed model is used to analyze the differences in person allocation between different types of households. The results indicate that life-cycle and household role, income, gender, employment status, and several types of constraints (activities including cost, time-availability, vehicle-availability, coordination constraints, and child-care obligations) affect person allocation decisions in the context of maintenance activities. The empirical results indicate the presence of various sources of correlations across persons, over activities, and within-household that are significant. In addition, the data also provides evidence that the unobserved variances in person selection utilities are not constant across households. A better understanding of these within-household interactions and between-household differences may be used in activity-based simulation models and to develop more effective and focused demand management measures. 相似文献