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171.
通过收费缓解交通拥堵的政治可行性取决于谁获得通行费收入。指出如果收益被分配给城市,特别是高速公路经过的城市,拥挤收费取得政治成功的可能性最大。与已有的很多建议不同,指出城市是比个体驾驶人和区域政府更有力的收益申索人。基于行为经济学和政治科学理论并结合几个大都市区的数据,对提议进行解析和阐述。在洛杉矶,潜在的拥挤收费收入估计每年接近50亿美元,将这些收入分配至高速公路经过的城市对拥挤收费的实施是有政治影响力和促进作用的。  相似文献   
172.
ABSTRACT

During the 1990s, Nigerian seaports were considered inefficient, unsafe due to massive cargo theft (wharf rat phenomenon) and one of the most expensive port systems in the world. This resulted in long turnaround times for ships and increased container dwell times. As a result, port operations were transferred to the private sector through concession contracts. This paper employs a Malmquist productivity index (MPI) technique to benchmark pre-and post-reform total factor productivity growth of the six major Nigeria seaports (Apapa, Calabar, Onne, Port Harcourt, TinCan Island and Warri) for the period 2000–2011 which represents six years before (2000–2005) and six years after (2006–2011) the reform. The results indicate progress in technical efficiency of the ports after reform but deterioration in technological progress. Overall productivity growth was higher in the pre-concession period compared to the post-concession period. The source of pre-concession period productivity growth was technological progress while the change in productivity of the post-concession period is generated by an increase in scale efficiency. This suggests that concessionaires have not brought in the much anticipated investment in modern technology to drive port efficiency. The ports of Calabar and Apapa experienced the highest productivity growth while lowest result was Onne.  相似文献   
173.
Travel time variability (i.e., random variations in travel time) leads to a travel time distribution for a repeated trip from a fixed origin to destination (e.g., from home to work). To represent travel time variability, a series of possible travel times per alternative (departure time, route or mode) are often used in stated choice experiments. In the traditional models, the probabilities associated with different travel scenarios (e.g., arriving early, on time and late) shown in the experiments are directly used as weights. However, evidence from psychology suggests that the shown probabilities may be transformed (underweighted or overweighted) by respondents. To account for this transformation of probabilities, this study incorporates perceptual conditioning through a non-linear probability weighting function into a utility maximisation framework, within which the empirical estimate of the value of expected travel time savings is estimated. The key advantage of this framework is that the estimated willingness to pay value can be directly linked to the source of utility (i.e., the probability distribution of travel time), while taking into account the perceptual transformation of probabilities.  相似文献   
174.
ABSTRACT

As outsourcing and offshoring continue to expand, the ocean container industry serves a critical and still increasing role in supporting global trade. Yet, perceived commoditization and intense price competition among ocean container carriers limit opportunities for competitive advantage and formation of long-term shipper–carrier relationships. This environment ultimately yields an unhealthy industry that threatens the stability of global supply chains. Extant literature provides limited insight into how carriers can build strong relationships with shippers to overcome the short-term, transactional-orientation of the industry. Examining a case study of a major ocean container carrier, we apply structural equation modeling to shipper survey data to explore how carrier operational, service, and pricing capabilities influence the strength of the long-term shipper–carrier relationship. Furthermore, we identify unique clusters of shipper needs, helping the carrier understand when and how to promote a particular portfolio of capabilities to customers.  相似文献   
175.
Abstract

The implementation history of the Coastal Zone Management Act offers insights into the process of long‐term intergovernmental policy implementation. This five‐stage history is explained as a coproduction process, in which coastal state, environmental, and development advocacy coalitions interacted with congressional committees and the federal coastal office to shape coastal policy and manage coastal development. The coproduction approach proved invaluable during the Reagan assault on the coastal program, when the states and Congress assumed responsibility for keeping the program alive. Acknowledging underlying stakeholder dynamics as the basis for coastal program evaluation could strengthen future coastal management implementation.  相似文献   
176.
During the last 20 years, the reefer shipping sector has been characterised by a gradual changing process, leading from specialised vessels to reefer containers. In fact, the reefer bulk fleet has experienced an irreversible decline, while the reefer container fleet has shown a continuous growth. This article investigates the current major factors shaping the reefer shipping industry, in order to understand the economic drivers inducing competition between bulk and containers. Therefore, a twofold analysis has been performed. First, an overview of the reefer market, including the cold chain, the demand for refrigerated products and the supply of reefer capacity given both by containership fleet and by conventional reefer fleet. Second, a specific case of the banana trade has been carried out for evaluating the revenues of each player involved in the banana cold chain followed by a cost analysis. The results reveal the market tendencies, focusing on the main sources of competition for bulk versus container.  相似文献   
177.
Abstract

Motorcycle activity in Asian economies is a significant contributor to carbon dioxide (CO2) emissions, both when moving and when idling at traffic lights. This paper investigates Taiwanese motorcyclists’ behavior of turning off the idling engine while stopping at traffic lights based on the theory of planned behavior (TPB), which recognizes that the achievement of voluntary change behavior can be identified by knowing an individual's attitudes (or behavioral intentions [BIs]) in the context of social norms (SN). A structural equation model system is used to identify candidate causal links between attitudes, SN, BI and behavior related to the idling stop behavior of motorcyclists. A partial least squares (PLS) model is built to correct the covariance matrix, given the relatively small sample size. Results suggest that attitudes, SN and perceived behavioral control, are significant determinants of idling stop BI at red lights.  相似文献   
178.
Abstract

The Commonwealth Constitution establishes the parameters for transport policy and administration in Australia. The first part of this paper outlines this Constitutional structure. Section 2 reviews current issues in Australian transport, illustrating the significance of the Constitutional constraints and the administrative framework. This framework and its associated responsibilities is set out in detail in Sections 3 and 4, first with respect to the Commonwealth's transport interests and then with respect to the States. South Australia is used as an example in the latter context but significant differences between States are noted. The final section summarizes inter‐governmental transport research organizations and discusses the potential of the Inter‐State Commission provided for in the Constitution.  相似文献   
179.
Abstract

This paper models trip generation for a cross-section of residential developments around the UK. Consistent with recent literature, the empirical model tests whether trip making patterns for residential developments are independent of car ownership and finds that trip generation is dependent upon car ownership socio-economic factors and site-specific characteristics, in particular land-zone type (e.g. town centre, out of town, etc.). However, public transport services are not found to have a significant relationship with trip generation; consequently, a policy implication of the results is that increasing bus services to residential developments is not associated with a reduction in generated trips.  相似文献   
180.
钢轨振动由沿钢轨传递的各类导波构成,是铁路滚动噪声的主要贡献者. 为了研究铁路轨道的动力特性,分别基于铁木辛柯梁理论和波导有限元法建立了两种分析模型,推导自由波响应和受迫响应的求解过程,以波数、群速度、速度导纳和衰减率为指标,分析了两种模型条件下钢轨的波导特性. 研究结果表明:波导有限元模型包含了钢轨横截面所有的变形特征,可表征6 kHz内钢轨中的8种导波及其特性,反映导波波型交换、群速度互换的现象,以及高阶导波激发引起的导纳峰值;铁木辛柯梁模型可识别包括弯曲波、扭转波和纵波在内的5种钢轨导波,无法揭示截止频率在1.5 kHz以上与钢轨截面变形相关的导波;铁木辛柯梁模型可给出2 kHz内合理的钢轨垂向原点速度导纳计算结果.   相似文献   
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