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741.
Abstract

Public perceptions of the risks and benefits of offshore oil development off the New England coast are examined. The influence of these perceptions on state policies toward federal actions is analyzed. A distinct trend of issue identification, critical analysis, consensus building, and state or regional action is observed. Throughout this interactive process between the region and the federal government, even though divergent state positions have evolved, there is a growing regional acceptance of coastal zone management concepts.  相似文献   
742.
The purpose of this paper is to investigate the net incidence of government subsidies to a transit system (i.e., the net impact of who pays and who benefits from transit subsidies). Rather than considering the U.S. transit subsidy program in the aggregate, the net incidence of subsidies to a particular transit system — Tidewater Regional Transit (TRT) — is analyzed. The paper concludes that the net incidence of the TRT subsidy program is progressive. Furthermore, the paper provides a methodology that can be used for investigating the net incidence of government subsidies to other transit systems.  相似文献   
743.
Coastal lands provide popular outdoor recreation opportunities including beach recreation, fishing, boating, and wildlife viewing. Published studies measuring the demand for access to coastal lands generally have focused on the recreational value of intensively used beaches, which comprise only a portion of the New England coastline. This article examines the recreational demand for coastal access to a local, free‐access site in southern New England. The study uses data obtained from on‐site interviews conducted during the summer of 1995 at Gooseberry Island, Massachusetts. The estimated average value of a visitor‐day during the summer season is $3.06 for weekdays and $4.18 for weekends and holidays. While these values are at the low end of the range of values published in existing literature addressing beach recreation, the aggregate value of recreation benefits derived from public access to undeveloped coastal areas likely are significant.  相似文献   
744.
The optimal trajectory from Calcutta port to Mumbai port is charted for a tanker transshipping from the East coast to the West coast of India during rough weather. Rough weather is simulated over Indian seas using the state-of-the-art WAM numerical wave model (WAMDI Group in J Phys Oceanogr 18:1775–1810, 1988), assimilating satellite (IRS-P4) wind fields. These simulated wave fields and two-dimensional (2D) directional wave spectrum are an absolute representation of the irregular seaway. Hence, the same for the monsoon month of August 2000 formed the input basis for this study. Loss of ship speed due to the wave field (i.e., nonlinear motion of the tanker in waves) and associated sea-keeping characteristics in the seaway are estimated (Bhattacharya in Dynamics of marine vehicles, Wiley, New York, 1978). The approach adopted in this paper is unique in that it takes into account both voluntary and involuntary speed reductions of the ship. It helps in ship tracking by the optimum route using inverse velocity as the weight function for the path in an efficient way. Dijkstra’s algorithm [Numer Math 1(3):269–271, 1959] is applied in an iterative manner for determining the optimum track. The optimum track information has broad scope for use in modern shipping industry for obtaining safe and least-time routing by avoiding schedule delays with economic fuel consumption.  相似文献   
745.
This paper provides an overview of the urban freight process, in the context of the supply and demand aspects of freight. A framework for analysis is developed, and within that framework, particular aspects of the urban freight process are described. Issues of concern from a public policy viewpoint are highlighted.

Seven main instruments related to public policy are introduced and their application described — taxes and subsidies, regulations, investment, operational instruments, planning, public ownership and research.

It is concluded that the importance of urban freight to the community and its relevance to urban transport justifies a higher level of attention in transport planning and policy formulation, and that there are a wide range of policy instruments available to enable this to be done. The objective of such planning and policy making needs to be specified in each specific context.  相似文献   
746.
Many industries are keeping pace with changing technology in an effort to improve operating efficiency and attract consumers with innovations. The transit industry is no exception, one example being the installation and operation of automatic fare‐collection (AFC) systems. There are many issues to consider in implementing an AFC system, including the type of equipment required and the expected quality of system performance.

This article presents a synthesis of several sources of information pertaining to AFC operations. It includes a discussion of system requirements, and the advantages and disadvantages of system operation. Performance measures of reliability and maintainability are also defined, and AFC systems are evaluated using these measures. Several conclusions are reached concerning current AFC practice.  相似文献   
747.
The impact of small compression ignition (CI) engine operation conditions and fuel properties on diesel and biodiesel particulate matters (PMs) quantity using opacity smoke meter is investigated. The biodiesel engine’s PMs are around a half of diesel engine PMs under the same engine operation conditions. Morphology of both engine’s PMs are also studied using a Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and image processing method. The average primary nanoparticle sizes of diesel and biodiesel engine’s PMs are approximately 34 nm and 32 nm, respectively. The result shows that engine operation condition and fuel property are strongly impact on the quantity and size distribution of primary nanoparticles emission. PM oxidation kinetics on conventional cordierite Diesel Particulate Filters (DPFs) powders by Thermo-gravimetric analysis (TGA) is also successfully studied. The calculated apparent activation energies of biodiesel engine’s PM oxidation on conventional cordierite DPFs powders are lower than that of diesel engine’s PM and carbon black because of unburned oxygenated molecule. The calculated apparent activation energy of biodiesel engine’s PM and diesel engine’s PM oxidize on conventional cordierite DPFs powders with pure air are in the range of 109 ~ 131 kJ/mole and 117 ~ 130 kJ/mole, respectively. It might be expected that smaller primary nanoparticle size of biodiesel engine’s PMs and bio-oxygenate unburned hydrocarbon can promote more PM oxidation rate during vehicle’s DPF regeneration process.  相似文献   
748.
The European Union project Eureka Logchain Footprint is an ongoing project to identify road and rail vehicles by means of their environmental footprint as characterised by dynamic load, noise, ground borne vibrations and gaseous emissions induced by the vehicle. Part of the project involves the installation of road and rail footprint monitoring stations throughout Europe. This paper presents results of the road stations in Switzerland and the UK. Individual vehicle data from weigh-in-motion and noise are compared. The results indicate that a significant number of vehicles surpass the limits set in both countries. It was shown that the UK sites are generating higher noise levels than their Swiss counterparts; in part due to the much coarser aggregate embedded in the running course of the pavement employed in the UK. Such data can be used to create an incentive for vehicle types with a low footprint and a penalty for vehicles with a large footprint.  相似文献   
749.
This study reveals areas where IMO regulations of safety of life at sea can be improved upon. After examination of 5389 mortality and 3559 accident cases of UK seamen and 6878 fatalities of worldwide seamen, it finds fatalities due to personal accidents on board ship constitute ~90% of all mortality cases. Therefore, prevention of personal accidents should be given a higher priority. It reveals also that accidents involving coastal (domestic) ferries were another concern in the safety of life in shipping, e.g. in 1996 alone more than 2562 fatalities occurred in this sector. As a case study, the nationalities of 364 deceased seamen in bulk carrier disasters (1990?1998) are identified. Fatalities to British and worldwide seamen are based on the data obtained from various sources. However, fatalities to seamen working on board open registry ships are the best estimation, based on the information available to the authors.  相似文献   
750.
珲春市是"一带一路"东起点,也是吉林省借港出海唯一通道。滨海2号路线为长春—吉林—珲春—扎鲁比诺港,将吉林省与俄滨海边疆区海港连接起来,实现东北货物南运出境不出国。由于珲春—扎鲁比诺港路线尚处起步阶段,集疏运条件需要培育、磨合的过程,相较形成规模的渤海湾港口通道存在劣势。首先对标营口港路线运费标准,确定珲春节点具有经济性的腹地范围,再根据腹地企业确定相关货种,在保证完成浙吉两省合作任务的同时,确保项目的经济合理性。  相似文献   
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