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101.
ZHENG Ke-wei BIAN Xin-qian SHI Xiao-cheng 《船舶与海洋工程学报》2007,6(1):15-20
It is an important control process to operate motion of an submergence rescue vehicle(SRV). Seeing that the motion of the submergence rescue vehicle is special, it is necessary to employ non-linear predictive control system. For this reason, continuous dynamic performance of the system, the logical components and the operative restraints are expressed as the non-linear equations of state with the inequality restraints, and the model principle of hybrid system is introduced. The conclusion shows that it comes true to exactly control position and attitude of the SRV by means of non-linear model predictive control. The test in a model basin has also proved that the above methods are efficient. 相似文献
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Clinicalresearchshowsthattheanalysisofpul monaryvesselshelpidentifyingearlyfeaturesofre piratorypathologicchanges.Pulmonaryvesselex ractionplaysanimportantroleinmedicalimage processingandanalysis.Moreover,theresultsof vesselsegmentationprovideatoolforunde… 相似文献
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强夯地基加固效果的评价主要是通过夯后的检测或夯前夯后的对比来表达,本文通过比较简要介绍了强夯加固效果检测方法及评价指标,以供参考。 相似文献
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This paper researches on a kind of control architecture for autonomous undelwater vehicle (AUV). After describing the hybrid property of the AUV control system, we present the hierarchical AUV control architecture. The architecture is organized in three layers: mission layer, task layer and execution layer. State supervisor and task coordinator are two key modules handling discrete events, so we describe these two modules in detail. Finally, we carried out a series of tests to verify this architecture The test results show that the AUV can perform autonomous missions effectively and safely. We can conclude the control architecture is valid and practical. 相似文献
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本文通过分析航运企业的产量、成本和盈利三者的关系,运用非线性盈亏平衡分析揭示航运企业固定成本、变动成本、单价、收入总额、利润等变量之间的内在联系规律,为航运企业的会计预测、决策和规划提供重要依据。 相似文献
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针对高层民用建筑加压送风防烟的特点,在分析建筑物内人员疏散方式的基础上,着重探讨了发生火灾时,层门的开启层数,选择加压送风口的型式,加压送风防烟系统的阻力计算. 相似文献
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3D Track-keeping Method for Autonomous Underwater Vehicle 总被引:1,自引:0,他引:1
WANG Wei Bian Xin-Qian Chang Zong-HuCollege of Power Nuclear Engineering Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(2):18-22
In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and strong coupled, an approach is used to divide it into two subsystems. One is to control the heading and the track error on the horizontal plane. The other is to control the pitch and the track error on the vertical plane. The results of computer simulation show that the autopilot works properly, it can capture the current waypoint and turns to track the next path automatically. 相似文献