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111.
Stated choice studies have been applied regularly to the valuation of time savings and other attributes of travelling as perceived by individuals. In such experiments, respondents often provide reference levels for the attributes and the hypothetical choices presented to them are pivoted around actual behaviour. However, most individuals are not able to provide reference levels for the number of casualties on the road they travel. Thus, if valuation of this important element is attempted, it is the researcher who must provide casualty risk reference levels to the respondents. Some studies have applied route choice experiments including a safety attribute but the majority has been limited to only one particular road section with a common baseline risk for all respondents.  相似文献   
112.
This paper deals with the importance of port choice and container terminal selection for deep-sea container carriers. The paper focuses on the research question: on what basis do deep-sea container operators select container ports (strategy) and container terminals (financial reasons) in the Hamburg–Le Havre range over others? In answering this research question, three dimensions are addressed in detail: the buying decision characteristics; port choice strategy; and terminal selection. The results show that strategic considerations at company level are important. For port choice the most important criteria from a carrier's perspective are: availability of hinterland connections; reasonable tariffs; and immediacy of consumers (large hinterland). In addition to these criteria, shipping lines attach great value to often neglected factors, such as feeder connectivity, environmental issues and the total portfolio of the port. The study reveals that port selection and terminal selection are not the same with terminal selection criteria mainly depending on: handling speed; handling costs; reliability; and hinterland connections. The analysis also brought forward that the decision making is different per container carrier, per trade and per port type, implying that a one size fits all approach is not relevant.  相似文献   
113.
This paper, using data envelopment analysis, assesses the efficiency of 122 iron ore and coal ports in 2005. Estimates for 54 loading and 68 unloading ports show that the main source of inefficiency in bulk terminals is related to the scale. Results aggregated at a country level demonstrate that the national efficiency can be achieved either through a limited number of large ports or by combining smaller ports with complementary characteristics—national network effect.  相似文献   
114.
Abstract

Cost–benefit analysis (CBA) plays a major role in the ex ante evaluation of rail projects in many western countries. At first sight carrying out a CBA for rail projects seems straightforward, since cost estimates are almost always available, and the most dominant benefits are generally known, being the travel time saved and the increase in consumer surplus due to induced demand. However, the practice is much more complex: the quality of current estimates for costs and benefits is often poor and several benefits-related aspects are ignored. This article gives an overview of the challenges in improving the quality of CBAs for rail projects.  相似文献   
115.
Abstract

The growing popularity of electric devices and the increasing number of hybrid and electric cars have recently raised concerns about the use of auditory signals by vulnerable road users. This paper consolidates current knowledge about the two trends in relation to cycling safety. Both a literature review and a crash data analysis were carried out. Based on a proposed conceptual model, knowledge gaps are identified that need to be addressed for a better understanding of the relation between limitations on auditory information while cycling. Results suggest that the concerns regarding the use of electronic devices while cycling and the advent of hybrid and electric vehicles are justified. Listening to music and conversing on the phone negatively influence cyclists’ auditory perception, self-reported crash risk and cycling performance. With regard to electric cars, a recurring problem is their quietness at low speeds. Implications of these findings in terms of cycling safety are discussed.  相似文献   
116.
沥青混合料烟雾与材料力学性能之间的关系   总被引:1,自引:0,他引:1  
着重于研究热拌沥青混合料生产过程中产生的烟雾与沥青力学性能之间的关系,涉及的影响因素有温度、沥青种类以及一些动力学参数。研究者在试验室拌和机上安装了气体取样设备,能够在正常拌和的同时对热拌沥青混合料烟雾中的多环芳香烃(PAH)以及有机化合物(TOC)进行取样分析。通过对沥青材料进行室内性能指标的测试,发现在所有指标中回收沥青的复合模量与沥青烟雾排放量的相关性最好,因为它的结果同时反映了材料的物理性能以及沥青氧化和老化的程度。同时还建立了热拌沥青混合料烟雾排放与拌和参数以及混合料力学性能之间的关系。  相似文献   
117.
In this paper the multi‐actor multi‐criteria analysis (MAMCA) method to evaluate transport projects is presented. This evaluation method specifically focuses on the inclusion of qualitative as well as quantitative criteria with their relative importance, defined by the multiple stakeholders, into one comprehensive evaluation process in order to facilitate the decision making process by the different stakeholders. The MAMCA methodology is introduced by an overview of other evaluation methods for transport projects in the past and is illustrated by means of two practical cases. The introduction will lead us to the theoretical conception of the MAMCA method where we draw the attention to the proven usefulness of the MAMCA for the evaluation of transport projects and the inclusion of different kinds of stakeholders, individuals as well as groups, into the evaluation process.  相似文献   
118.
宜巴高速公路界岭隧道横洞进正洞挑顶施工方案比选   总被引:1,自引:0,他引:1  
宜巴高速公路界岭隧道施工中,由于复杂的地质状况和处理坍塌历时过长,整个隧道工程严重滞后建设项目工期。因此,决定增设横洞,从横洞向正洞掘进,增加主洞工作面,以满足项目建设进度要求。文章详细介绍了增设横洞两种方案的施工工艺,在技术可行、经济合理基础上,针对界岭隧道横洞垂直贯穿进入正洞和曲线渐变过渡施工转入正洞的施工方案进行了分析对比。  相似文献   
119.
Ad hoc shared ride trip planning (SRTP) utilizes mobile devices, geo-sensors and wireless networks to match on-the-fly individual travel demand with transport supply. It represents one of many alternatives to single occupancy vehicle use. This paper outlines a SRTP approach via a two-phase algorithm based on user preferences in a time-dependent routing. Whereas current algorithms use minimization of travel time as the only optimization criterion in trip planning, in the framework presented here, the user can specify multiple trip preferences including travel time, walking time, number of transfers between cars and trip length. Various scenarios are simulated in the city of Tehran (Iran) to demonstrate how preference settings affect the routes of ad hoc shared journeys.  相似文献   
120.
West and Central Africa ports have historically not paid much attention to environmental issues. In the past decade, however, environmental concerns are beginning to emerge with pockets of innovative responses to environmental risks as the ports undergo institutional and infrastructural reform – most notably, with concessions to multinational terminal operators. In this article, environmental management processes in the ports of Abidjan (Ivory Coast), Douala (Cameroon), Lagos (Nigeria) and Tema (Ghana) are compared. Three aspects of ecological modernization theory: changing role of the state, growing involvement of economic actors and economic incentives, and shifting roles for civil society organizations are focused on to analyse the dynamics of their environmental reform. Findings suggest that globalization processes are a common major trigger in enhancing a gradual but still fragmented and limited process of environmental reform in West and Central Africa ports, but paces and pathways of the reform are influenced by national politico-administrative arrangements rooted in colonial legacies. Consequently, understanding and advancing environmental reform processes of West and Central Africa ports requires following trends and significant developments but also taking into account national historical trajectories.  相似文献   
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