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801.
Earthquakes and tsunamis pose significant threats to Pacific Northwest coastal port and harbor communities. Developing holistic mitigation and preparedness strategies to reduce the potential for loss of life and property damage requires community-wide vulnerability assessments that transcend traditional site-specific analyses. The ability of a geographic information system (GIS) to integrate natural, socioeconomic, and hazards information makes it an ideal assessment tool to support community hazard planning efforts. This article summarizes how GIS was used to assess the vulnerability of an Oregon port and harbor community to earthquake and tsunami hazards, as part of a larger risk-reduction planning initiative. The primary purposes of the GIS were to highlight community vulnerability issues and to identify areas that both are susceptible to hazards and contain valued port and harbor community resources. Results of the GIS analyses can help decision makers with limited mitigation resources set priorities for increasing community resiliency to natural hazards.  相似文献   
802.
This paper elaborates on the definitions of inter and multi-modal transport, as well as their differences in terms of performance. A survey of the barriers, both internal and external, to an efficient intermodal transport is included followed by an analysis of the advantages and disadvantages of combining rail transport with the other transport modes. Transhipment technologies for efficient freight service and some examples of freight rail corridors between sea and inland terminals are presented. The integration between air and rail transport is discussed and the potential synergies between air and high-speed rail services are emphasised. The paper concludes with a discussion on energy use for sustainable rail performance.  相似文献   
803.
This paper presents a calculation method for the pressure fluctuation induced by a cavitating propeller. This method consists of two steps: the first step is the calculation of propeller sheet cavitation, and the second step is the calculation of pressure fluctuation on the ship stern. It is for practicality that we divide the method into two steps but do not calculate these steps simultaneously. This method is based on a simple surface panel method “SQCM” which satisfies the Kutta condition easily. The SQCM consists of Hess and Smith type source panels on the propeller or cavity surface and discrete vortices on the camber surface according to Lan’s QCM (quasi-continuous vortex lattice method). In the first step, the cavity shape is solved by the boundary condition based on the free streamline theory. In order to get the accurate cavity shape near the tip of the propeller blade, the cross flow component is taken into consideration on the boundary condition. In the second step, we calculate the cavitating propeller and the hull surface flow simultaneously so as to calculate the pressure fluctuation including the interaction between the propeller and the hull. At that time, the cavity shape is changed at each time step using the calculated cavity shape gotten by the first step. Qualitative agreements are obtained between the calculated results and the experimental data regarding cavity shape, cavity volume and low order frequency components of the pressure fluctuation induced by the cavitating propeller.  相似文献   
804.
In this article we describe the development of a tool that allows planners to efficiently and effectively plan space within valuable areas of a shipyard. Traditionally, space is considered as resource; however, it is difficult to accurately account for and plan its consumption with the currently available planning software’s. The spatial scheduling tool described in this article can be used by planners to manually or automatically reserve space within the shipyard for construction of large blocks over the entire erection period of the ship. The software is coupled with a heuristic optimization solver inspired by an algorithm used for "3D bin-packing problems." The result is the ability to efficiently generate and compare multiple space allocation alternatives in a reduced time with the ultimate goal of maintaining the critical ship erection schedule. A better solution than manual or semi-automatic allocation of blocks can be obtained through the optimization module.  相似文献   
805.
Abstract

It was pointed out in a recent article on shorelines management in France that no overall coastal management legislation in that country exists.1 Nevertheless, certain existing legislation has been adapted to take account of the peculiarities of the shoreline and coastal zone, and new institutions such as the “Shorelines Trust”; have been created.2 As is the case with most countries in the Western world, the processes of urbanization, industrialization, and recreational development place tremendous pressure on shoreline use. Resulting conflicts are sometimes difficult to solve unless adequate institutional frameworks exist. Some form of institutional change is thus inevitable.  相似文献   
806.
The simulations performed show that demand for quality tankers has to increase by 30% for a two-tier tanker market to emerge. The two-tier freight structure will only last for 3–5 years due to contracting induced by higher freight rates. This means that OPA does not by itself result in higher freight rates for tankers that comply with the requirements. If Western Europe also closes their trades to substandard tankers, a two-tier market emerges and quality tankers obtain a premium. The paper presents a simulation model for international tanker markets. The non-linear complementary equilibrium model solves for a sequence of static equilibria in segmented tanker freight markets, shipbuilding and scrapping markets. Freight markets are segmented according to quality requirements for tankers. The model specifies three tanker classes and one—quality tankers—can operate both market segments.  相似文献   
807.
In this paper, a tramp ship routing model of fleet deployment in a hub-and-spoke network is presented. This model simultaneously determines the selection of hubs, the assignment of spokes to hubs, the deployment of feeder-containerships as well as containership routing between spokes and spokes, hubs and spokes, and hubs and hubs. Even though some parts have been studied, this complex combination of shipping problems has never been addressed. Because the problem is NP-hard, a genetic algorithm (GA) with local search is proposed. In the algorithm, a cut-off procedure is applied to fleet deployment in a sub-route strategy. A number of randomly generated problem instances are solved by both a mathematical program and the GA with local search. A simple but realistic heuristic algorithm is also developed. Both the GA with local search and the heuristic algorithm are used to solve a number of real case instances. A comparison of the results shows the efficiency of the GA with local search. The developed model can be used as a route-decision support tool for shipping companies that provide long-haul shipping services in a hub-and-spoke network.  相似文献   
808.
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   
809.
This paper presents a comment on some of the key issues relating to piracy, terrorism, regulatory approaches and economic issues stemming from maritime security measures. It takes a wide ranging view of these issues and argues that security measures must be managed effectively so as not to be perceived as burdensome. Furthermore, any measures adopted must cover the whole of the international logistics supply chain and not just the shipping component of such distribution channels.  相似文献   
810.
This paper presents a design of boundary controllers implemented at the top end for global stabilization of a marine riser in a three dimensional space under environmental loadings. Based on the energy approach, nonlinear partial differential equations of motion, including bending-bending and longitudinal-bending couplings for the risers are derived. The couplings cause mutual effects between the three independent directions in the riser’s motions, and make it difficult to minimize its vibrations. The Lyapunov direct method is employed to design the boundary controller. It is shown that the proposed boundary controllers can effectively reduce the riser’s vibration. Stability analysis of the closed-loop system is performed using the Lyapunov direct method. Numerical simulations illustrate the results.  相似文献   
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