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701.
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   
702.
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   
703.

A numerical method for solving 3D unsteady potential flow problem of ship advancing in waves is put forward. The flow field is divided into an inner and an outer domain by introducing an artificial matching surface. The inner domain is surrounded by ship wetted surface and matching surface as well as part of the free surface. The free surface condition for the inner domain is formulated by perturbation about the double-body flow or uniform incoming flow assumption. The outer domain is surrounded by matching surface and the rest free surface as well as infinite far-field radiation boundary. The free surface condition for the outer domain is formulated by perturbation about uniform incoming flow. The simple Green function and transient free surface Green function are used to form the boundary integral equation (BIE) for the inner and outer domains, respectively. Taylor Expansion Boundary Element Method (TEBEM) is utilized to solve the double-body flow and inner domain and outer domain unsteady flow BIE. Matching conditions for the inner domain flow and outer domain flow are enforced by the continuity of velocity potential and normal velocity on the matching surface. Direct pressure integration on ship wetted surface is used to obtain the first-order and second-order wave forces (moments). The numerical predictions on the displacement, added resistance, sway mean drift force and yaw mean drift moment of the modified KVLCC2 ship at different forward speeds are investigated by the proposed TEBEM method. It is also compared with the other numerical results. The physical tank experiment results are also developed to validate the accuracy of numerical tank results. Compared with the experiment solutions, a good agreement can be obtained by TEBEM method.

  相似文献   
704.
As a signatory to the Convention on Biological Diversity, Canada has committed to establishing a network of marine protected areas (MPAs) that effectively conserves at least 10% of coastal and marine areas by 2020. Research shows that the most effective MPAs are large, well enforced, no-take, and designed as part of a network. Canada's Pacific MPAs, designated site-by-site, cover approximately 3% of Canadian Pacific waters. We investigated how these MPAs could effectively contribute to Canada's national network by analyzing the implementation of management intent through the application of fisheries closures and conducting a preliminary assessment of their size and spacing relative to scientific guidelines. Fisheries closures outside of MPAs were similarly assessed. Results showed that 90% of existing MPAs were intended to exclude commercial fishing, yet only 2.5% fully or partially met this goal, therefore management intent was not achieved. Further, existing MPAs were small, 75% less than 10 km2 in size, but were reasonably spaced, from one to 50 km apart. While a suite of fisheries closures may be better suited to effectively contribute to a network than MPAs without fisheries closures, they would require permanent designations and management plans to meet network inclusion criteria.  相似文献   
705.
SUPPRESSIONOFGROWTHOFAHUMANLIVER-DERIVEDCELLLINEBYENDOGENOUSLYPRODUCEDPARATHYROIDHORMONE-RELATED PEPTIDELIHusong;P.K.Seitz,P....  相似文献   
706.
Due to environmental concerns and safety regulations in the automotive industry, the development of strong and lightweight cars has been a hot issue in the last decade. One solution for this purpose would be to use high-strength steel (HSS) and advanced high-strength steel (AHSS). These materials can make the car lighter while maintaining the crash resistance of the vehicle. HSS and AHSS have more resistance force in the die structure compared with conventional steel due to their higher yield and tensile strength and thus, these materials have a greater effect on die deformation during the sheet metal forming process. As a result, die deformation can affect the blank sheet’s drawn pattern, strain, and stress as well as springback. This study presents a sheet metal forming simulation that considers die deformation. The simulation process was compared with conventional simulation methods. Our results indicate that the sheet metal forming simulation with die deformation consideration provides useful information on the die structure as well as formability and springback.  相似文献   
707.
Emissions of CO2, as the main component of greenhouse gases, and high fuel consumption rates are worldwide problems. To solve them, most car manufacturers have concentrated on developing various techniques to improve the efficiencies of engines and transmissions and ECO-ROUTEs to meet environmental regulations. In this study, an algorithm for determining routes that cause the least fuel consumption was developed. The core of this algorithm is a specific EEC (energy efficiency constant) map containing logic that is able to predict fuel consumption. The accuracy of the algorithm was confirmed by vehicle tests for various driving patterns. Parameters affecting vehicle fuel economy were studied and verified. Improvement in the accuracy of this algorithm was confirmed by applying these parameters to ECO-ROUTE logic.  相似文献   
708.
709.
Numerical analysis is used to optimize the gate shape of the mold part in the molding process. The objective of this research was to develop a procedure that will optimize the gate shape of the mold part by using Design of Experiments approach. The computer-aided engineering software Moldflow was used to simulate the plastic injection molding process and the Minitab software was used to analyze the computational results from Moldflow. The Bulk Molding Compounds (BMC) UNI-203S thermoset material was chosen as the molding material. Four different types of gate shapes were analyzed to find the gate shape to be used in the optimization. The Type 3 gate shape was selected as basis for the gate optimization because this shape yielded the minimum shear rate around the gate among all. The thickness, width, length and angle of the gate were selected as the design variables. Erosion around a gate due to repetitive shear flow during molding process was considered as an important issue to extend the service life of the expensive mold. It is normally very difficult to prevent erosion due to high injection pressure and repetitive use of the mold, especially in certain molding parts as BMC reflector in automotive parts, so it has become the subject of researches. The effectiveness of design variables was evaluated by observing shear rate around the gate. The objective of the optimization was to minimize the average shear rate around the gate. Response Surface Method was applied to identify the optimum values of the design variables. The computed optimum values were validated numerically. The optimized gate shape showed the reduced shear rate by about 11%.  相似文献   
710.
By high particulate matter(PM) reduction performance, diesel particulate filter(DPF) is applied to almost all of modern HSDI diesel engine. PM emitted from diesel engine is consist of carbon based and non-carbon based material. Representative carbon based PM is soot. Non-carbon based PM is produced by wear of engine and exhaust component, combustion of lubrication oil and sulphur in fuel. Accumulation of non-carbon based PM affects pressure difference of DPF and thus accuracy of soot mass estimation in DPF can be lowered during normal and regeneration condition when the pressure difference caused by non-carbon based PM is not recognized correctly. Also unevenly accumulated PM inside of DPF can produce locally different exhaust gas temperature and thus it can lower accuracy of soot mass estimation during regeneration. This study focuses on estimation of soot oxidation rate not by conventional pressure difference but by exhaust gas analysis at up and downstream of DPF. Results, strong correlations between CO2 -fuel mass ratio and soot oxidation was observed.  相似文献   
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