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981.
In this paper, we develop a general random utility framework for analyzing data on individuals’ rank-orderings. Specifically, we show that in the case with three alternatives one can express the probability of a particular rank-ordering as a simple function of first choice probabilities. This framework is applied to specify and estimate models of household demand for conventional gasoline cars and alternative fuel vehicles in Shanghai based on rank-ordered data obtained from a stated preference survey. Subsequently, the framework is extended to allow for random effects in the utility specification to allow for intrapersonal correlation in tastes across stated preference questions. The preferred model is then used to calculate demand probabilities and elasticities and the distribution of willingness-to-pay for alternative fuel vehicles.  相似文献   
982.
Success in the shipping industry depends to large extent on the quality of the main asset: the ship. The owner or operator will ask herself: do I have the right ship for a certain job, and what performance can I achieve with a given ship. The relationship between the specifications of the ship, which are fixed in the design stage, and the economic performance of the ship has received some attention, but most of the previous work lacks in the extent to which economic performance is measured or expressed.

This paper describes an attempt to operationalize the concept of design for service in the maritime industry. The paper presents a lengthy review of previous work, which shows that some attention was devoted in the past to the relationship between economic and technical aspects of shipping. However, the 'economics' usually turned out to be simple cost calculations, instead of clear insight in costs and benefits of certain design decisions. The main variable for the shipowner to buy a ship, or to operate a ship on a certain route is earnings potential. The relation between technical specifications and earnings potential is fairly direct: desired earnings potential influences the design specifications, and the specification of the finished ship determine the earnings potential. The analysis in this paper shows that shipowners also consider cargo carrying capacity, speed and versatility, but no other, more detailed, design factors.

Subsequently, we present the design for service framework for the shipping industry. This framework points the attention to a thorough service requirements analysis that drives the design stage. Finally, some preliminary work is presented on empirical studies that are currently developed in the Netherlands.  相似文献   
983.
The paper is to explore the relation between national economic development and the formulation of maritime policy. It collects and examines data from 30 maritime nations, and shows that maritime policy is determined by economic circumstance rather than the result of rational decision of policy makers. A general solution is produced for an optimum maritime policy under a given economic condition. The general solution can serve as a benchmark for future maritime policy making and research in general.  相似文献   
984.
This paper explores critical success conditions of collaborative planning projects in the area of urban transport, evaluating the impact of new collaborative methods, instruments and processes on project performance. Hypothesis building is based on a comparative, empirical research design, rather than on deductive theory construction. Potential critical success conditions are derived from literature. Based on five urban transport planning projects in Gothenburg (Sweden), London (United Kingdom), Milwaukee (United States), Tokyo (Japan) and Mexico City (Mexico), a rough set analysis of the five cases reveals validated success conditions, which can be used for formulating hypotheses for further research or for policy and process improvement. The results suggest that a dedicated management of the multi-actor network, a high diversity of actors, as well as an extensive use of knowledge integration methods in combination with a high network density are critical success conditions of these planning processes. Surprisingly, the extensive use of unilateral methods also showed to be an important success condition. The traditional role of the planner will have to be complemented with the expertise of network and methodology management. The authors conclude that rough set analysis can be a valuable addition to narrative, single-case analysis of collaborative urban transport planning processes.  相似文献   
985.
The paper presents a study on the incorporated probability that a tanker fleet meets a given permissible value of hull girder strength loss. The analysis was based on a database of hull girder section modulus (HGSM) for as-gauged girth belts of tankers. It was found that its mean value is below 5% over the entire life span of the analyzed tanker fleet. The Weibull probabilistic distribution was found to best represent the time-varying HGSM loss. A method was developed for calculating the incorporated safety of a fleet. As an example, the IMO requirement for a maximum HGSM reduction of 10% relative to its required value was analyzed, accounting for time-variant HGSM loss and including a probabilistic model for coating longevity. The views expressed in the paper are those of the authors and not necessary those of ABS.  相似文献   
986.
Intelligent Transport Systems (ITS) have a wide range of applications. They range from the more traditional signal coordination system to concepts such as smart cars and smart roads. This paper describes transit‐based ITS measures in Singapore. The island‐state has plans to double the current 90 km rail network over the next ten years and has also implemented or committed to implement many ITS initiatives that impact upon the public transport systems. The aim of these investments is to achieve a high transit modal share using a comprehensive transit network. ITS measures that can promote this aim include: automatic vehicle location systems for buses and taxis, integrated transit fare systems using contactless smart cards, rail information systems, multi‐modal travel guides on Internet and electronic road pricing. The potential impacts of these measures are delay reduction, more comfort, productivity gain and better network accessibility. ITS measures do not necessarily add physical capacity to a public transport system but are excellent supporting measures to encourage the modal shift to transit, particularly if a quality transit system is already in place.  相似文献   
987.
The critical component of all emission models is a driving cycle representing the traffic behaviour. Although Indian driving cycles were developed to test the compliance of Indian vehicles to the relevant emission standards, they neglects higher speed and acceleration and assume all vehicle activities to be similar irrespective of heterogeneity in the traffic mix. Therefore, this study is an attempt to develop an urban driving cycle for estimating vehicular emissions and fuel consumption. The proposed methodology develops the driving cycle using micro-trips extracted from real-world data. The uniqueness of this methodology is that the driving cycle is constructed considering five important parameters of the time–space profile namely, the percentage acceleration, deceleration, idle, cruise, and the average speed. Therefore, this approach is expected to be a better representation of heterogeneous traffic behaviour. The driving cycle for the city of Pune in India is constructed using the proposed methodology and is compared with existing driving cycles.  相似文献   
988.
989.
990.
This study aims to identify the determinants of certified helmet use among postal delivery riders (PDRs) in rural areas of Peninsular Malaysia. A cross-sectional study was done among 269 PDRs from 50 postal distribution centres (DC) nationwide. Data collection was achieved through observation of the helmets and a questionnaire. The quality of the motorcycle helmets was determined by the presence of the certification label issued by the Standards and Industrial Research Institute of Malaysia (SIRIM). The response rate was 99.3%. The odds of full-shell helmets having the SIRIM label were 37.1 times more than that of the half-shell helmets. The odds of non-purchased helmets having the SIRIM label were 14.9 times more than that of the purchased helmets. The odds of expensive helmets having the SIRIM label were 4.4 times more than that for cheaper motorcycle helmets. The odds of helmets owned by riders without a previous crash history having the SIRIM label were 1.9 times more than helmets owned by riders with a crash history. Full-shell helmets with SIRIM standard certification, non-purchased helmets, helmet price of US$11.00 or more, and motorcycle riders without any previous crash history were determinants that contributed towards the use of a certified motorcycle helmet. Multiple logistic regression indicated that two variables significantly predicted the use of a certified motorcycle helmet among PDRs – helmet type and cost. An employer that provides the employees with full-shell motorcycle helmets with SIRIM standard certification label that costs at least US$11.00 and hiring motorcycle riders without any previous crash history gives a higher chance of compliance with standard certified motorcycle helmet usage.  相似文献   
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