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991.
客车集便器污水处理方案研究和设计应用 总被引:2,自引:0,他引:2
通过对国内客车集便污水处理方案的调研,结合某新建客运专线动车整备所的环境条件,对集便器污水的水质及处理工艺进行了研究;选择了预曝气、SBR法污水处理工艺。 相似文献
992.
杜万英 《铁道标准设计通讯》2005,(12):12-14
天津市区至滨海新区快速轨道交通工程轨道采用无缝线路,先进行场焊,在场内将钢轨焊成125 m的长轨条,然后进行现场焊接,形成无缝线路。本工程根据现场的施工特点,采用移动式气压焊,保证了施工质量与施工进度。 相似文献
993.
LIU Jian-cheng LIU Xue-min XU Yu-ruCollege of Shipbuilding Engineering Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(1):21-25
In this paper, maximum-likelihood (ML) and its relaxation algorithm, which are used to identify the mathematicsmodel of an underwater vehicle(UV), arc discussed. With the trial data of zigzag tests, the hydrodynamic derivatives of theUV were estimated, and the relaxation algorithm is confirmed to have better astringency from the contrast between the twomethods.Then a simulation environment based on these parameters is established to verify the validity and effect of these meth-ods. The result shows the model is credible and the methods are very useful for the research of maneuverability and adaptivecontrol of underwater vehicles. 相似文献
994.
FEA for designing of floating raft shock-resistant system 总被引:2,自引:0,他引:2
ZHAOYing-long HELin HUANGYing-yun WANGYu 《船舶与海洋工程学报》2003,2(1):24-29
Choosing the equipment with good shock-resistant performance and taking shock protection measures while designing the onboard settings, the safety of onboard settings can be assured when warships, especially submarine subjected to non-contact underwater explosion, that is, these means can be used to limit the rattlespace (i. e. , the maximum displacement of the equipment relative to the base) and the peak acceleration experienced by the equipment. Using shock-resistant equipments is one of shock protection means. The shock-resistant performance of the shock-resistant equipments should be verified in the design phase of the equipments. The FEA (finite element analysis) software, for example, MSC. NASTRANw, can be used to verify the shock-resistant performance. MSC. PATRAN and MSC. NASTRAN are used for modeling and analyzing the floating raft vibration isolating equipment. The model of the floating raft and the floating raft vibration isolating system are theoretically analyzed and calculated, and the analysis results are in agreement with the test results. The transient response analysis of the system model follows the modal analysis of the floating raft vibration isolating system. And it is used to verify the shock-resistant performance. The analysis and calculation method used in this paper can be used to analyze the shock-resistant performance of onboard shock-resistant equipments. 相似文献
995.
996.
Hermann J. Klein 《WMU Journal of Maritime Affairs》2007,6(2):167-175
This paper offers an overview about how societal issues and environmental challenges will influence shipbuilding in the near
future. It begins with an evaluation of societal developments and refers to globalization and climate change. The paper then
continues to assess the impact of these developments on ship design and operation, and considers how the adverse effects of
shipping in this context can be reduced. In this respect, topics like emission control and scrapping of ships are considered. 相似文献
997.
本文结合工程实际,对城市道路地下管线设计的综合协调程序、各种管线的特点和排布原则以及管线的间距和交叉等提出建议,以期与广大同仁互相交流设计经验,共同提高管综设计水平。 相似文献
998.
Adopting an elastic-viscoplastic, the asymptotic problem of mode I propagating crack-tip field is investigated. Various asymptotic
solutions resulting from the analysis of crack growing programs are presented. The analysis results show that the quasistatically
growing crack solutions are the special case of the dynamic propagating solutions. Therefore these two asymptotic solutions
can be unified. 相似文献
999.
1000.