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101.
<正>英国石油公司(BP)非常关注船舶质量,希望通过审查,降低风险,降低事故率。为此,BP在世界上建立了很多检查网点,如新加坡、上海、墨尔本、伦敦,鹿特丹、休斯顿以及芝加哥等,都设有专门机构。同时,BP还有一支由70名经过认证的检查员组成的检查队伍,他们在全世界范围内进行检查,然后提交相关报告。  相似文献   
102.
Patrick.C 《游艇业》2009,(6):78-79
夏季是乘风破浪的最佳季节,热爱冒险刺激的你渴望出海扬帆,注重生活品质的你又需要保护好皮肤——航海防晒,就成为了航行之前,你不可不做的”功课”。只需要一点点时间和心思,将以下7点身体力行,你就可以尽享在碧波蓝天下,驯服烈日的快乐。  相似文献   
103.
104.
The free trade agreement (FTA) implemented in 1988 by the United States and Canada will complete the integration of the economics of the world's two largest trading partners. While the vast bulk of US-Canadian trade is transported overland, the FTA will also affect the volume, commodity composition, and spatial distribution of maritime trade. The spatial structure of US-Canadian water-borne trade is examined followed by an investigation of the short-run (non-investment related) impacts of the FTA on the US port system. Commodity-specific analyses of tariffs and non-tariff barriers and elasticities of demand are employed to estimate the sectoral and spatial changes in water-borne trade volumes since 1988 that are attributable to the FTA.  相似文献   
105.
Over the last decade, a large number of high capital cost transportation projects have been proposed for the New York City Region. Many have resulted from addressing evolving capacity needs, changes in regional demographics and economics, meeting the improvements necessitated by operating century old subway systems and recognizing the impact of moving freight in a dense region. But the catalyst for bringing all of these projects to the attention of the public and all regional agencies was the tragedy of September 11, 2001. While these projects entail massive investments ($50–$60 billion), little analytical work has been carried out to measure the transportation and economic costs and benefits they entail and to categorize them accordingly. Competition among agencies to secure adequate resources to implement any of the desired projects makes such analysis necessary; yet there still remain political, vested economic interests and agency rivalry barriers to achieving this important planning objective. This paper reports the methodological approach taken by these authors for consistent and transparent project evaluation and then presents results from the ranking and prioritizing methodology. The policy underpinnings and implications of the analysis are discussed in a subsequent paper and thus only briefly touched upon here in the concluding section.  相似文献   
106.
This paper presents an analysis of telecommunications and travel costs for typical business meetings. It is contribution to the debate on the substitutability of telecommunications for travel. An underlying assumption which supports the substitution hypothesis is that the cost of traversing distance through the use of telecommunication is lower than the cost of travelling.This paper addresses the relative cost of telecommunications and travel in conducting interactions. Three factors are assumed to determine these costs: distance, duration of interaction and number of participants. The analysis assumes that cost alone affects choice, and ignores other communication qualities.The relationship between telecommunication and travel costs was tested quantitatively through a case study of typical business meetings in the U.S., based on data from 1988. The results show that travel costs are lower than telecommunication costs for shorter distances, and that the relationship between telecommunications and travel costs differs substantially as a function of number of participants and meeting duration. Because of ongoing rapid changes in the costs of both of these interaction modes, the complex competition between them will continue. The implications of the findings for location decisions and policy-making are discussed.  相似文献   
107.
This article presents the economic rationale for road pricing and provides some scale on the magnitude of peak period tolls that might be justified. It discusses the impacts of such tolls on congestion, air quality and economic development and suggests a long term strategy towards areawide implementation of peak period pricing. It discusses current trends which are increasing the likelihood for implementation of congestion pricing and toll roads in the future. In particular, it discusses some aspects of the 1991 Intermodal Surface Transportation Efficiency Act (ISTEA) which will eliminate some of the current restraints on congestion pricing and toll highways.Abbreviations ETC Electronic toll collection - FHWA Federal Highway Administration - HOV High occupancy vehicle - ISTEA Intermodal Surface Transportation Efficiency Act - LOS Level of service - TCM Transportation control measure - V/C Volume-to-capacity ratio - VMT Vehicle mile(s) of travel - vphpl Vehicles per hour per lane  相似文献   
108.
The objectives of this review-based paper were twofold. Firstly, we aimed to explore the need and possibilities for broadening the scope of highway planning by taking account of the residential context, including residential satisfaction. Satisfaction appears to be an interesting, and in our opinion, valuable mediating planning concept between road infrastructure planning and the accompanying external effects on the one hand and household coping strategies on the other. Households living near highway infrastructure are influenced by both positive (i.e. accessibility gains) and negative road-related factors (e.g. noise nuisance and air pollution). Changes in these factors may trigger people to accept the new situation, adjust preferences, try to influence plans and/or even relocate. The second aim was to gain a greater understanding of the influence of both accessibility characteristics and negative externalities on the residential context of households. With respect to context, we make a distinction between residential satisfaction, housing prices and residential relocation. We see changes in residential satisfaction as a potential early predictor of opposition to plans, not only from active opposers but also from the more ‘silent majority’, and as a predictor of housing price changes and residential migration. Insights into residential satisfaction around highways may help transportation planners to relieve locational stress and may also prevent protests and relocations. Our literature review indicated that households prefer to live close to highways to benefit from high regional accessibility, but do not want to contend with the nuisances. This is also reflected in property values. However, the literature appears to put more emphasis on studying the impact of (regional) accessibility and externalities on location behaviour than on residential satisfaction. Because of the added value that the concept of residential satisfaction may provide in road planning, and the limited scientific insights, it is important to gain greater insight into how residential satisfaction is influenced by negative and positive externalities and into how residential satisfaction changes over time—from the stage when new road projects are discussed through to concrete planning, realization and the period after completion. Moreover, it would be worthwhile to gain a deeper understanding of the extent to which house prices, location behaviour and residential satisfaction near highways interrelate.  相似文献   
109.
Climate change poses known and unknown risks for coastal communities and also challenges for university faculty and local government staff who communicate about cli- mate sciences. Conceived as a way to move beyond traditional models of science communication, this project involved public and private decision makers in specific at-risk communities in Oregon (U.S. Pacific coast) and Maine (Atlantic coast). Both state projects sought to move behavior toward decisive action that results in coastal communities that are more resilient to climate variability at all scales. To promote engagement between project staffs and publics, a dialogic model of communication was advanced, beginning with interviews and focus groups that in turn shaped further engagement through workshops and targeted video products. This means of communication led to a deeper understanding of participants’ knowledge, beliefs, perceptions, values, and barriers to action related to climate change and its effects. Coinciding with this, project participant evaluations in both Oregon and Maine indicate that the workshops and videos were successful at informing them on this complex issue; and in both states, project participation led to action outcomes. We believe that applied elsewhere our multifaceted and adaptive approach will garner similar results, provided sufficient dedicated staffing and attention to methods.  相似文献   
110.
Electric vehicles with individually controlled drivetrains allow torque-vectoring, which improves vehicle safety and drivability. This paper investigates a new approach to the concurrent control of yaw rate and sideslip angle. The proposed controller is a simple single input single output (SISO) yaw rate controller, in which the reference yaw rate depends on the vehicle handling requirements, and the actual sideslip angle. The sideslip contribution enhances safety, as it provides a corrective action in critical situations, e.g., in case of oversteer during extreme cornering on a low friction surface. The proposed controller is experimentally assessed on an electric vehicle demonstrator along two maneuvers on surfaces with significantly varying tire-road friction coefficient. Different longitudinal locations of the sideslip angle used as control variable are compared during the experiments. Results show that: i) the proposed SISO approach provides significant improvements with respect to the vehicle without torque-vectoring, and the controlled vehicle with a reference yaw rate solely based on the handling requirements for high-friction maneuvering; and ii) the control of the rear axle sideslip angle provides better performance than the control of the sideslip angle at the center of gravity.  相似文献   
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