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51.
Hot weather events, ventilation assets, changing passenger demand and service expectations have all caused increased attention on thermal comfort on London’s Tube. This study provides estimates of the future number of days when passengers travelling on sections of the Tube could be subjected to thermal discomfort under future scenarios of climate change, and the potential number of passengers dissatisfied. A risk based methodology is presented, integrating a spatial weather generator modified for urban areas and a thermal comfort model. The study provides an initial assessment of adaptation options by considering the implications of lowering train temperatures by 2 °C and 4 °C to represent saloon cooling. Median results under a 2050 high scenario indicate that all Tube lines assessed could experience near-complete passenger dissatisfaction with the thermal environment in trains in the unlikely event that nothing else were to change. Adaptation aimed at lowering train temperatures has the potential to provide tangible improvements in thermal comfort. However, this was not projected to be sufficient to maintain comfortable thermal conditions for many of the lines in the 2050s under high emission scenarios, requiring a combination of other infrastructure cooling measures to be implemented in parallel. 相似文献
52.
张慧慧 《辽宁省交通高等专科学校学报》2013,(6):20-22
目前,大型石质文物亟需一种新型无损检测技术来现场检测其病害情况。本文通过物理模拟方法,应用红外热成像无损检测技术对太阳照射下不同湿度岩石的热像变化特征作了实验研究,验证了应用红外热成像技术检测石质文物渗水病害的可行性。 相似文献
53.
摩托车风冷式发动机难以解决高性能带来的热负荷问题,也不可能随着性能的提高再增加单位散热面积。为此,水冷方式的摩托车发动机所具有的冷却效果愈来愈受到人们的青睐,已成为先进发动机冷却系统的首选。 相似文献
54.
Gang Fan Yihong Guan Jiatao Zhang Honggang Wang Kunming University of Science Technology Kunming China 《上海交通大学学报(英文版)》2000,(1)
IntroductionLaserphasetransformationhardeningisanewtechnologyduringwhichlaserheatresourceactsdirectlyonsurfaceofmaterialandcompositionscharacteristicofmaterialischanged.Thetechnologyproce8sesacharacterofrapidheatvelocity,highheattempelatureandquickcoolingspeed(l0'col0'aC/s).Thecompositionandcharacteristicofmaterialvariedwithvariousinnertemperaturewillleadtothermalresidualstress.Itiswellknownthattheresidualstressaffectssignificantlyoncharacteristicofmaterial,suchasimProvingstrengthoffatigUere… 相似文献
55.
随着新能源汽车热管理行业的迅猛发展,整体竞争格局形成了两大阵营。一类是以综合性热管理方案为主的国际巨头,另一类是以专一性热管理产品为代表的国内主流热管理零部件企业。并且随着电气化升级,热管理领域新生零部件迎来了增量市场,在新能源汽车新增的电池冷却、热泵系统以及其他电气化升级带动下,热管理方案中运用的部分零部件种类随之发生变化。本文主要通过对新能源热管理领域竞争格局以及核心部件的技术发展分析,对电池热管理、整车空调系统、电驱动及电子元器件等关键技术部件进行了详细综述与分析,并对新能源汽车热管理行业技术发展趋势进行了综合预判。 相似文献
56.
本文主要介绍新能源汽车热管理远程云控制的应用和设计思路,利用手机APP、后台中央计算机、车载通信终端、汽车CAN局网络等技术实现新能源汽车热管理的远程控制,使用户更加便捷地了解和控制车辆的当前冷热状态,可以有效提高新能源车辆的使用安全性和舒适性。 相似文献
57.
Chang Doo Jang Tae Hoon Kim Dae Eun Ko Thomas Lamb Yun Sok Ha 《Journal of Marine Science and Technology》2005,10(4):211-216
In a shipyard, line heating and triangle heating are two major processes carried out by skilled workers to form curved plates
in various shapes under various heating conditions. There have been many studies on line heating, but triangle heating has
rarely been studied owing to its complicated heating process with irregular multiheating paths and highly concentrated heat
input. Triangle heating is the most labor-intensive job. Hence, it is essential for most shipyards to study the automation,
as well as the improvement, of the triangle heating process in order to increase hull-forming productivity. In this study,
a pioneering attempt to simulate triangle heating was made. A circular disk-spring model is proposed as an analysis model
for the elastoplastic procedure of triangle heating, and the inherent strain method is also used to analyze the deformation
of plates. The results of the simulation were compared with those of experiments and showed good agreement. It is shown that
the present approach and the model used in this study are effective and efficient for simulating triangle heating for the
steel plate forming process in shipbuilding. 相似文献
58.
Hydrography and biogeochemistry of the north western Bay of Bengal and the north eastern Arabian Sea during winter monsoon 总被引:1,自引:0,他引:1
K.K. Balachandran C.M. Laluraj R. Jyothibabu N.V. Madhu K.R. Muraleedharan J.G. Vijay P.A. Maheswaran T.T.M. Ashraff K.K.C. Nair C.T. Achuthankutty 《Journal of Marine Systems》2008,73(1-2):76-86
The north eastern Arabian Sea and the north western Bay of Bengal within the Indian exclusive economic zone were explored for their environmental characteristics during the winter monsoons of 2000 and 2001 respectively. The two regions were found to respond paradoxically to comparable intensities of the atmospheric forcing. There is an asymmetry in the net heat exchange of these two basins with atmosphere because of the varying thickness of barrier layer. During winter, the convective mixing in the Arabian Sea is driven by net heat loss from the ocean, whereas the Bay of Bengal does not contribute to such large heat loss to the atmosphere. It appears that the subduction of high saline Arabian Sea water mass is the mechanism behind the formation of a barrier layer in the northeast Arabian Sea; whereas that in the Bay of Bengal and the southeast Arabian Sea are already established as due to low saline water mass. The weak barrier layer in the Arabian Sea yields to the predominance of convective mixing to bring in nitrate-rich waters from the deeper layers to the surface, thereby supporting enhanced biological production. On the other hand, the river discharge into the Bay of Bengal during this period results in the formation of a thick and stable barrier layer, which insulates vertical mixing and provide oligotrophic condition in the Bay. 相似文献
59.
《铁道标准设计通讯》2017,(5):105-108
为研究地下水对冻土地区桩基础的影响,针对现有冻土桩基试验设备的不足,对加载系统、位移采集系统等加以改进,并利用可调发热电阻作为热源,研制一套能够模拟地下水热效应的室内桩基模型试验装置,通过标定试验,确定装置模拟地下水热效应时的各项参数。利用该装置,开展不同地下水位置、有无地下水工况下的桩基承载力试验,对地下水热效应对单桩极限承载力的影响进行分析,其试验结果能够与理论模型计算较好的吻合,装置能够良好模拟地下水热效应。 相似文献
60.