首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   475篇
  免费   12篇
公路运输   61篇
综合类   12篇
水路运输   132篇
铁路运输   8篇
综合运输   274篇
  2022年   3篇
  2021年   7篇
  2020年   7篇
  2019年   5篇
  2018年   19篇
  2017年   13篇
  2016年   14篇
  2014年   16篇
  2013年   104篇
  2012年   20篇
  2011年   24篇
  2010年   24篇
  2009年   27篇
  2008年   21篇
  2007年   16篇
  2006年   19篇
  2005年   8篇
  2003年   12篇
  2002年   2篇
  2001年   6篇
  2000年   3篇
  1999年   4篇
  1998年   8篇
  1997年   5篇
  1996年   5篇
  1995年   4篇
  1994年   4篇
  1993年   3篇
  1992年   3篇
  1991年   4篇
  1990年   4篇
  1989年   5篇
  1988年   1篇
  1987年   7篇
  1986年   1篇
  1985年   7篇
  1984年   5篇
  1983年   4篇
  1982年   5篇
  1981年   5篇
  1980年   6篇
  1979年   5篇
  1978年   4篇
  1977年   6篇
  1975年   6篇
  1974年   3篇
  1973年   1篇
  1972年   2篇
排序方式: 共有487条查询结果,搜索用时 195 毫秒
191.
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   
192.
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   
193.
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   
194.
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   
195.
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   
196.
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   
197.
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   
198.
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   
199.
There is a growing interest in traveller behaviour research to explore alternative information processing strategies (often referred to as heuristics or rules) adopted by individuals when assessing packages of attributes describing alternatives in a choice set, and making a choice. One popular attribute processing rule relates to attributes not being considered (i.e., being ignored), for all manner of reasons, referred to in the small but growing literature as attribute non-attendance or non-preservation. Researchers have used a mixture of methods to study the role of attribute non-attendance, including supplementary questions on whether each attribute is ignored or not, and methods in which the functional form of the utility expressions defining an alternative can recognise the possibility, up to a probability, of an attribute being ignored. Although supplementary questions are worthy of further consideration, despite the controversy as to the reliability of the response, recent interest has focused on ways to establish the incidence of attribute non-attendance without recourse to such evidence. In this paper we use an existing data set of choice amongst four attributes describing alternative car non-commuting trips, to illustrate the proposed method, and to compare values of travel time savings under each possible combination of non-attendance attributes relative to a model in which all attributes are assumed to be fully attended to. The paper reveals a major concern with the way that attribute levels and ranges are selected in the design of choice experiments, which can induce non-attendance situations where willingness to pay estimates cannot be obtained.  相似文献   
200.
Agent-based microsimulation models of transportation, land use or other socioeconomic processes require an initial synthetic population derived from census data, conventionally created using the iterative proportional fitting (IPF) procedure. This paper introduces a novel computational method that allows the synthesis of many more attributes and finer attribute categories than previous approaches, both of which are long-standing limitations discussed in the literature. Additionally, a new approach is used to fit household and person zonal attribute distributions simultaneously. This technique was first adopted to address limitations specific to Canadian census data, but could also be useful in U.S. and other applications. The results of each new method are evaluated empirically in terms of goodness-of-fit.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号