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201.
引言在对海员的职业培训中 ,有关如何作出符合伦理道德的决定的培训也应当包括其中。当我们在对他们进行传统的如轮机、航海、人员管理以及通讯等培训时 ,不要忘记 ,教给他们有关道德和道德思维的基础知识同样重要。在这个竞争激烈、全球一体的商业世界中 ,我们必须承认这样一句格言 :成功的商人必为有德者。所以 ,对海员的培训 ,既应当教给他们有关伦理道德的历史 ,还应进行具体的案例学习 ,更重要的是 ,应通过有关范例的讨论和学习 ,使他们掌握进行道德决定的模式和方法 ,并指明解决问题的方向。对此 ,位于缅因州的国际道德研究院的Rus… 相似文献
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This paper proposes a nonlinear adaptive sliding mode control that aims to improve vehicle handling through a Steer-By-Wire
system. The designed sliding mode control, which is insensitive to system uncertainties, offers an adaptive sliding gain to
eliminate the precise determination of the bound of uncertainties. The sliding gain value is calculated using a simple adaptation
algorithm that does not require extensive computational load. Achieving the improved handling characteristics requires both
accurate state estimation and well-controlled steering inputs from the Steer-By-Wire system. A second order sliding mode observer
provides accurate estimation of lateral and longitudinal velocities while the driver steering angle and yaw rate are available
from the automotive sensors. A complete stability analysis based on Lyapunov theory has been presented to guarantee closed
loop stability. The simulation results confirmed that the proposed adaptive robust controller not only improves vehicle handling
performance but also reduces the chattering problem in the presence of uncertainties in tire cornering stiffness. 相似文献
205.
This paper focuses on identifying crash risk factors associated with injury severity of teen drivers. Crash data obtained from the Highway Safety and Information System (HSIS) for the entire state of North Carolina, for years 2011 to 2013, was used for analysis and modeling. Among all the crashes during the study period, a total of 62,990 crashes involving teen drivers (15 to 19?years) were analyzed. A partial proportionality odds model was developed to identify factors contributing to injury severity of teen drivers. The results obtained indicate that teen drivers driving sports utility vehicles and pickup trucks are more likely to be severely injured when compared to teen drivers driving passenger cars. Teen drivers are more likely to be severely injured on weekdays, particularly during peak hours. The chances of teen drivers getting involved in severe injury crashes on Tuesdays and Fridays is higher when compared to Sundays. Age, gender, road configuration, terrain, adverse weather condition, and access control are observed to have a significant effect on teen driver's injury severity. 相似文献
206.
Sven-Olov Daunfeldt Niklas Rudholm Ulf Rämme 《Transportation Research Part A: Policy and Practice》2009,43(3):306-309
This paper studies the impact of the Stockholm road pricing trial on retail revenues. The analysis is performed using revenue data from 14 shopping malls, 9 within the tool area and 5 outside the tool area. The data also include revenue data from a sample of retail stores located along the main shopping streets in Stockholm. The results show that the Stockholm road pricing trial did not negatively affect retail revenue, neither in shopping malls nor in the sample of retail stores. 相似文献
207.
This paper discusses current research for development of model-based generic algorithms for design and control of reconfigurable interdependent systems. This work is based on extension of Graph Trace Analysis (GTA), which was originally developed in the 1990s for power distribution system design. Because of GTA's ability to combine and restructure analysis methodologies from a variety of problem domains, it is now being used for integrated power distribution and transmission system design, operations, and control. Over the last few years research has begun to formalize GTA into a multidiscipline approach that uses generic algorithms and a common model-based analysis framework. The paper provides an overview of the concepts used in GTA, and then discusses how GTA and generic algorithms can be used together for design and control of multidiscipline systems. This new approach includes decoupling component and system level equations, using iterators to structure iterative analysis that simplifies coordination of discrete events and also eliminates the need for large matrices, using composition to implement polymorphism and simplify data management, using dependency components to structure analysis across different systems types, and implementation of hot-swappable algorithms. 相似文献
208.
This research examines the potential for short sea shipping services on the east coast of North America, and focuses on the factors that freight shippers use to choose a transport mode. While there is significant literature available on modal choice and carrier selection, very little examines the effect of splitting the business on the choice that shippers specifically make between short sea and trucking options. Contrary to existing literature, we find that shippers' perceptions of short sea are favourable in this market. We also identify a new method of collecting data on how companies split business in these decisions. 相似文献
209.
The key features of the western Galician shelf hydrography and dynamics are analyzed on a solid statistical and experimental basis. The results allowed us to gather together information dispersed in previous oceanographic works of the region. Empirical orthogonal functions analysis and a canonical correlation analysis were applied to a high-resolution dataset collected from 47 surveys done on a weekly frequency from May 2001 to May 2002. The main results of these analyses are summarized bellow. Salinity, temperature and the meridional component of the residual current are correlated with the relevant local forcings (the meridional coastal wind component and the continental run-off) and with a remote forcing (the meridional temperature gradient at latitude 37°N). About 80% of the salinity and temperature total variability over the shelf, and 37% of the residual meridional current total variability are explained by two EOFs for each variable. Up to 22% of the temperature total variability and 14% of the residual meridional current total variability is devoted to the set up of cross-shore gradients of the thermohaline properties caused by the wind-induced Ekman transport. Up to 11% and 10%, respectively, is related to the variability of the meridional temperature gradient at the Western Iberian Winter Front. About 30% of the temperature total variability can be explained by the development and erosion of the seasonal thermocline and by the seasonal variability of the thermohaline properties of the central waters. This thermocline presented unexpected low salinity values due to the trapping during spring and summer of the high continental inputs from the River Miño recorded in 2001. The low salinity plumes can be traced on the Galician shelf during almost all the annual cycle; they tend to be extended throughout the entire water column under downwelling conditions and concentrate in the surface layer when upwelling favourable winds blow. Our evidences point to the meridional temperature gradient acting as an important controlling factor of the central waters thermohaline properties and in the development and decay of the Iberian Poleward Current. 相似文献
210.
Leonardo J. Basso Sergio R. Jara-Díaz 《Transportation Research Part A: Policy and Practice》2012,46(6):890-900
We model and analyze optimal (welfare maximizing) prices and design of transport services in a bimodal context. Car congestion and transit design are simultaneously introduced and consumers choose based on the full price they perceive. The optimization variables are the congestion toll, the transit fare (and hence the level of subsidies) and transit frequency. We obtain six main results: (i) the optimal car-transit split is generally different from the total cost minimizing one; (ii) optimal congestion and transit price are interdependent and have an optimal frequency attached; (iii) the optimal money price difference together with the optimal frequency yield the optimal modal split; (iv) if this modal split is used in traditional stand-alone formulations – where each mode is priced independently–resulting congestion tolls and transit subsidies and fares are consistent with the optimal money price difference; (v) self-financing of the transport sector is feasible; and (vi) investment in car infrastructure induces an increase in generalized cost for all public transport users. 相似文献