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821.
The term ‘Piracy’ tends to be used in a loose, popular sense to refer to various acts of violence or lawlessness at sea which are not, strictly speaking, acts of piracy in law. In this article, the author examines the concept of piracy under international law and related notions such as hijacking and mutiny. In this context, he shows that the ‘malpractices’ of robber bands in such places as the inshore waters of Nigeria and The Philippines are not acts of piracy jure gentium.  相似文献   
822.
823.
Rising sea level potentially poses a threat to many coastal areas, thereby possibly affecting coastal environments, including human assets. Taking into account the precau--tionary principle demanded at the Framework Convention for Climate Change in Rio de Janeiro in 1992, coastal managers and planners are required to evaluate the possibility of both physical and economic impacts of sea-level rise. However, long-term and cost-intensive data capture is often not affordable for a first estimation of general trends. To determine physical and economic impacts on a spatial scale of less than 10 km, a rapid and low-cost method is required. A Geographic Information System (GIS), in combination with readily available data and two coastal behaviour models (the Bruun-GIS Model and the Aggradation Model) was applied to simulate shoreline recession caused by a rise in sea level. In addition, the potential impacts of a 50-year design storm were considered in conjunction with sea-level rise. The monetary vulnerability was assessed and combined with the simulated recession rates. This procedure provides a first estimate on the potential risk a locality (here Collaroy/Narrabeen Beach) may face due to the impacts of sea-level rise and/or coastal storms. Overall, the modelling outcome suggests that long-term erosion problems associated with rising sea level are less significant in comparison with those impacts associated with short-term coastal storm events for Collaroy/Narrabeen Beach.  相似文献   
824.
Abstract

The recently adopted Law of the Sea (LOS) Convention contains a provision allowing coastal nations to adopt 12‐mile territorial seas. Already 104 nations (of a total of 137 coastal nations) have claimed territorial seas of 12 miles or wider. The paper discusses the factors which, in the opinion of the authors, could cause the United States to broaden its territorial sea from the present 3 miles to 12 miles within the next half‐dozen years or so. The state‐federal ocean use and resource management issues that will be raised by such a move are reviewed and options for dealing with the jurisdictional issues are developed. Given the political and economic volatility of these issues and their complexity, the use of a broadly representative and well‐staffed study commission to formulate a course of action is suggested.  相似文献   
825.
将分布式监控系统引入到机务段油库油罐监控系统,通过分布式系统管理和控制喷淋降温、火警灭火、液位监测、输油等子系统的方法,实现了油库油罐监控的自动控制和数据管理。  相似文献   
826.
在舰机协同反潜的作战过程中,由于引导及攻击占位的因素而影响直升机引导水面舰艇鱼雷攻击效果的主要误差源包括引导直升机位置误差、探测距离误差、探测方向误差、攻击水面舰艇位置误差、占位航向误差和占位速度误差.本文在对上述的各种误差源的误差传递过程进行分析的基础上,采用了蒙特卡罗法进行了计算,得出了各种误差源对攻击效果的影响.通过对计算结果的分析,得出提高引导、攻击兵力平台的导航及定位精度对鱼雷引导攻击的效果具有很大的作用的结论.  相似文献   
827.
This study examines the cold performance of biodiesel blends in a passenger car and a light duty truck at −16 °C and −20 °C. Six different types of biodiesels derived from soybean oil, waste cooking oil, rapeseed oil, cottonseed oil, palm oil and jatropha oil were blended with different volume ratios (B5 (5 vol. % biodiesel — 95 vol. % diesel), B10 and B20). The cold filter plugging point (CFPP) and the cloud point had an effect on the startability and driveability of both the passenger car and the light duty truck. The startability and driveability of the passenger car with all biodiesel blends (B5) were generally good at −20 °C. In the light duty truck, biodiesel blends (B10 and B20) of soybean, waste cooking, rapeseed and jatropha tended to be good at −20 °C in the startability and driveability tests than the biodiesel blends (B10 and B20) of cottonseed and palm. In particular, the palm biodiesel blend (B10) failed at −20 °C, and the palm biodiesel blend (B20) also failed at −16 °C in the startability test. The cold flow properties of biodiesel dictate that the length of the hydrocarbon chains and the presence of unsaturated structures significantly affect the low temperature properties of biodiesel.  相似文献   
828.
Subjective well-being related to satisfaction with daily travel   总被引:1,自引:0,他引:1  
Previous research demonstrates an impact on subjective well-being (SWB) of affect associated with routine performance of out-of-home activities. A primary aim of the present study is to investigate whether satisfaction with daily travel has a positive impact on SWB, either directly or indirectly through facilitating the performance of out-of-home activities. A secondary aim is to determine whether emotional-symbolic or instrumental reasons for car use results in higher satisfaction with daily travel than other travel modes. A survey of a population-based sample of 1,330 Swedish citizens included measures of car access and use, satisfaction with daily travel, satisfaction with performance of out-of-home routine activities, and affective and cognitive SWB. The results confirmed that the effect on affective and cognitive SWB of satisfaction with daily travel is both direct and indirect via satisfaction with performance of activities. Percent weekly car use had a small effect on satisfaction with daily travel and on affective SWB, although fully mediating the effect of satisfaction with performance of the activities. This suggests that car use plays a minor role for satisfaction with daily travel and its effect on SWB. This role may be larger if investigated after a forced reduced car use.  相似文献   
829.
Uncertainty is inherent in major infrastructure projects, but public decision-making for such projects ignores it. We investigate the uncertainty about the future effects of tearing down the Alaskan Way Viaduct in downtown Seattle, using an integrated model of housing, jobs, land use and transportation, on outcomes including average commute times. Our methodology combines the urban simulation model UrbanSim with the regional transportation model. We assess uncertainty using Bayesian melding, yielding a full predictive distribution of average commute times on 22 different routes in 2020. Of these routes, 14 do not include the viaduct and eight do. For the 14 base routes that do not include the viaduct, the predictive distributions overlap substantially, and so there is no indication that removing the viaduct would increase commute times for these routes. For each of the eight routes that do include the viaduct, the 95% predictive interval for the difference in average travel times between the two scenarios includes zero, so there is not strong statistical support for the conclusion that removing the viaduct would lead to any increase in travel times. However, the median predicted increase is positive for each of these routes, with an average of 6 min, suggesting that there may be some measurable increase in travel time for drivers that use the viaduct as a core component of their commute.  相似文献   
830.
Turbocharging port-injected Natural Gas (NG) engines allows them to recover gaseous-fuel related power gap with respect to gasoline engines. However, turbolag reduction is necessary to achieve high performance during engine transient operations and to improve vehicle fun-to-drive characteristics. Significant support for the study of turbocharged Compressed Natural Gas (CNG) engines and guidelines for the turbo-matching process can be provided by 1-D numerical simulation tools. However, 1-D models are predictive only when a careful tuning procedure is set-up and carried out on the basis of the experimental data. In this paper, a 1-D model of a Heavy-Duty (HD) turbocharged CNG engine was set up in the GT-POWER (Gamma Technologies Inc., Westmont, IL, US) environment to simulate transient operations and to evaluate the turbolag. An extensive experimental activity was carried out to provide experimental data for model tuning. The model buildup and tuning processes are described in detail with specific reference to the turbocharger model, whose correct calibration is a key factor in accounting for the effects of turbine flow pulsations. The second part of the paper focuses on the evaluation of different strategies for turbolag reduction, namely, exhaust valve variable actuation and spark timing control. Such strategies were aimed at increasing the engine exhaust-gas power transferred to the turbine, thus reducing the time required to accelerate the turbocharger group. The effects of these strategies were examined for tip-in maneuvers at a fixed engine speed. Depending on the engine speed and the applied turbolag reduction strategy, turbolag reductions from 70% to 10% were achieved.  相似文献   
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