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111.
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   
112.
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   
113.
Asia-Pacific countries with divergent economic and political backgrounds developed a regime of bilateral free trade agreements in response to globalization. Challenged by the 1997 and 2008 financial crises, this Asian trade regime has remained intact, although the most powerful stakeholders have changed positions, as indicated by the strong emergence of China in the past decade. Efforts of key trading partners to tackle non-tariff barriers (e.g., rule of origin and customs formalities) in the region have yielded little progress thus far. Instead of aiming at a regional consensus on non-tariff barriers by all member states, a global supply chain (GSC) approach is recommended. Mature hub ports at strategic locations with advanced institutional measures could set up international trade facilitation centers co-locating multinational customs formalities. This GSC approach may also be adopted to construct a GSC hub development model that explains the transformation of hub ports.  相似文献   
114.
Port authorities increasingly need to communicate with a variety of external stakeholders in order to maintain and strengthen the societal acceptance of seaport activities. The availability of socio-economic impact studies on port authority and regional development agency websites has often made this information accessible to the public at large. However, the differences in methodologies adopted, in terms of selecting, defining and measuring various types of socio-economic impacts, sometimes lead to misconceptions as well as misleading comparisons across ports within and between regions. In this paper, we suggest guidelines for the design and application of a potential best practice from an interregional perspective (UK, France and Belgium), based on research in the framework of a European Commission co-funded project, ‘IMPACTE’. The paper also aims to develop guidelines for comparing the socio-economic impacts of ports across regional and national borders and discusses the development of a European port economic impact measurement toolkit. We analyse a sample of 33 recent socio-economic impact assessment reports in terms of methodologies adopted and types of impacts measured. The review shows a great diversity among these studies, leading to important differences between the impacts of port activity communicated to stakeholders.  相似文献   
115.
This paper seeks to determine the effects of uncertainty in out-of-vehicle times on route choice. Data were collected at two key interchanges in Auckland, New Zealand. Previous work modelled the data using a manual approach to fuzzy logic. This study extends that work by automating the process through defining a black-box function to match the survey data, then employing a genetic algorithm to fine-tune the fuzzy logic model. Results show that automation and the genetic algorithm improve the model’s capability to more accurately predict ridership. The tuning of the membership functions is conducted twice, first using initial fuzzy rules and again after the fuzzy rules have been adjusted to reduce disparity between the output and survey data. The calibrated membership functions provided for operational (transfer waiting and walking time and delay) and physical attributes (safety and seat availability) can be used by practitioners to determine an estimated ridership.  相似文献   
116.
Most transportation research in the United States uses cross-sectional, “snapshot” data to understand levels of car access. Might this cross-sectional approach mask considerable variation over time and within households? We use a panel dataset, the Panel Study of Income Dynamics (PSID), for the years 1999–2011 to test this question. We find that for most families, being “carless” is a temporary condition. While 13 % of families in the US are carless in any given year, only 5 % of families are carless for all seven waves of data we examine in the PSID. We also find that poor families, immigrants, and people of color (particularly, blacks) are considerably more likely to transition into and out car ownership frequently and are less likely to have a car in any survey year than are non-poor families, the US-born, and whites.  相似文献   
117.
Unmet travel needs can be defined as trips and activities that people need or would like to do more, but for a variety of reasons they are prevented from doing so. This paper provides a critical evaluation of the literature focused on unmet travel needs, with the aim of assessing the scope of existing studies on this topic and better understanding the full context of older people’s mobility. This narrative review identifies how travel needs in later life have been assessed, and the barriers that affect the ability of older people to fulfil these needs. Due to the heterogeneity of older people and differences in research approaches, the analysis of the literature is not conclusive in terms of identifying the real impact of the analysed variables and measures on unrealised mobility. Nevertheless, of the studies analysed, on average at least one-third of older people report unmet travel needs. This situation was found to worsen with age, and women were reported to be more affected than men. The pursuit of leisure, and in particular visiting friends and family, was found to be the activity most associated with unmet travel needs.  相似文献   
118.
Integrated land use and transportation forecasting models are used to assist decision-makers in the policy analysis and infrastructure capital improvement selection process. These models are typically given precise, point-estimate inputs that are mathematically linked, through a series of submodels, to forecasted model outputs. These point-estimate inputs represent an unrealistic level of precision and a growing body of research is focusing on statistical techniques to model uncertainty in model inputs and parameters and tracking the effects of this uncertainty through the various submodels to the model outputs. This paper presents an uncertainty analysis of the Large Zone Economic Module (LZEM) of the Simple, Efficient, Elegant, and Effective Model (SE3M) of land use and transportation. Three case-study implementations of the model are used to obtain a reasonably sound approximation of how uncertainty affects LZEM outputs: Guam, Puerto Rico, and Oahu, Hawaii. These case studies were the subject of an early transferability study with SE3M and were selected based on both their insularity and diverse physical, economic, and demographic geographies. The findings of this research demonstrate that LZEM has a robust framework, with the potential to estimate error both in the positive and negative direction under uncertain input/parameter conditions.  相似文献   
119.
The biogeochemistry of the sulfur cycle in a ca. 5-m-long sediment core from the eastern slope (221 m water depth) of the Landsort Deep in the west-central Baltic Sea was investigated by analyzing the solid phase records of sulfur isotopes and pyrite textures, besides selected main and minor elements. The sediments were deposited during post-glacial history of the Baltic Sea when the basin experienced alteration of brackish (Yoldia Sea, Littorina Sea) and freshwater (Baltic Ice Lake, Ancylus Lake) conditions. The stable isotopic composition of total sulfur was analyzed as a function of depth. In selected samples pyrite (FeS2), greigite (Fe3S4), and barite (BaSO4) fractions were separated for isotope analyses. Pyrite textures were analyzed by SEM and optical microscopy.Microbial reactions associated with the oxidation of organic matter resulted in assemblages of authigenic sulfide minerals which for the post-Ancylus Lake brackish water environment are dominated by pyrite and for freshwater environments by Fe-monosulfides. The sulfur isotopic composition of the brackish water Littorina Sea sediments (δ34S between −40 and −27‰ vs. V-CDT) is believed to be determined by cellular sulfate reduction rates and reactions involving intermediate sulfur species. The availability of reactive iron and decomposable organic matter as well as sedimentation rate and the chemocline position are important variables upon the δ34S values of sulfides in brackish water environment. The syn-depositional abundance of sulfur and organic matter, and transport of dissolved sulfur species vs. rates of microbial reactions determine δ34S in the freshwater sediments. The upper part of the Ancylus Lake sediments is sulfidized by downward diffusing H2S and/or sulfate from overlying brackish water sediments. Minor concretionary barite formation in the freshwater sediments is most likely due to the reaction of pore water sulfate diffusing downward from brackish water sediments with barium desorbed from freshwater sediments. The size distribution of pyrite framboids in the brackish sediments indicates that the formation mainly occurred from anoxic pore waters, although some pyrite formation in an anoxic water column cannot be excluded.  相似文献   
120.

A methodology for comparing phased implementation plans for a new fixed guideway transit system in an urban area is presented. Four assumptions are made: (1) the guideway system replaces existing or planned bus service, (2) superior service on the new system results in increased ridership when compared to buses; (3) presence of the guideway facility redirects outward urban growth resulting in additional ridership, and (4) conversely, the absence of any action on the new guideway facility reinforces a diffuse urban growth pattern that creates an irreversible loss of transit ridership. The economic comparision of alternative plans includes total as well as “relative” inflation of principal cost components. A key feature of the proposed methodology is including in the comparisons the costs of private automobile mileage that could have been replaced by transit. These costs are expressed as “fuel” and “all other” automobile costs; favorable transit system implementation schedules can then be identified as a function of parametrically assumed values for these two unit costs. A hypothetical example demonstrates the proposed method.  相似文献   
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