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排序方式: 共有2084条查询结果,搜索用时 31 毫秒
61.
船体三维网格的自动生成算法及其图形用户界面的设计 总被引:2,自引:1,他引:1
本文介绍的三维湿表面网格的自动生成算法,不但可完成型值表各站型线的等弧长插值拟合,而且能够在沿船长方向的任意位置上进行站的加密和插值,从而自动生成三维湿表面网格。该算法的实现依赖于一套完整的图、形用户界面。此界面用Unix平台的Motif、C和GL编制,友好灵活,方便易用。 相似文献
62.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):331-350
This paper presents an integrated structure for a passive and active fault tolerant control (FTC) design approach in the framework of a robust nonlinear control technique called Dynamic Surface Control (DSC). As motivated by the automated vehicle application, we consider two categories of possible faults: pre-specified (a priori) and non-specified faults. It is first shown that DSC can be considered as a passive FTC approach in the sense that it gives simultaneous robust stability to a set of nonlinear systems even in the presence of model uncertainties and the pre-specified faults. Then, the non-specified fault is classified depending on the fault’s impact on the closed-loop system and isolatability from a fault detection and diagnosis (FDD) system. If a fault is both intolerable and isolatable, an active FTC approach is taken which includes FDD and controller reconfiguration. More specifically, trajectory reconfiguration is considered to accommodate the actuator fault, i.e., to compensate for the performance loss due to the fault within the framework of a switched hierarchical structure. Finally, the integrated structure for the longitudinal control of an automated transit bus is designed through the proposed method. Simulation results of the fault tolerant controller are shown for both single and multiple multiplicative faults. This controller was implemented on the California PATH transit buses in a demonstration of automated public transportation technology in San Diego, California in August of 2003. 相似文献
63.
通过对河北省高速公路路面屡次出现裂缝的现象进行调查分析,并结合秦皇岛市京沈高速公路大修工程的实践,综合分析了路面产生裂缝的主要原因,并提出有效防治裂缝产生的措施和建议. 相似文献
64.
65.
沥青混凝土热铺层厚度测量仪设计 总被引:1,自引:0,他引:1
胡忠录 《筑路机械与施工机械化》2012,29(7):65-67
针对在公路养护与沥青混凝土路面摊铺过程中,沥青混凝土的厚度控制对施工成本、路面平整度、路面质量及验收结果的影响,设计了一种能够精确测量沥青混凝土热铺层厚度的实用新型厚度测量仪,克服了目前公路工程施工中沥青混凝土热铺层厚度测量技术中的缺点与不足 相似文献
66.
Shin Hyung Rhee Boris P. Makarov H. Krishinan Vladimir Ivanov 《Journal of Marine Science and Technology》2005,10(4):173-180
This study was concerned with the free-surface wave flow around a surface-piercing foil. The volume of fluid method implemented
in a Navier–Stokes computational fluid dynamics code was employed. Three widely used discretization schemes for the volume
of fluid method were assessed for a test case that involved general ship waves, spilling breaking waves in front of the leading
edge, and bubbly free surfaces in separated regions. A single computational approach was selected for the comparison, and
a grid-dependence study was carried out. The computational results were validated against existing experimental data, showing
good agreement. The validation results suggest that all three discretization schemes perform well, but the best and most efficient
results were obtained using the high-resolution interface capturing scheme. 相似文献
67.
Based on a shield-driven running tunnel project of Hangzhou Metro Line 2, this paper carries out field measuring of the ground surface deformation caused by two different shield machines in double-tube tunnelling in soft soil areas, obtains the laws of the surface deformation caused by shield-driven double-tube tunnelling and verifies the applicability of the modified Peck formula to double-tube tunnelling. The results show that in soft soil areas the impacts on ground surface deformation caused by different shield construction parameters in the previously and subsequently excavated tunnels are different, while the surface deformation changes sharply before and after the shield machine passing through the cutting face, and a rebound phenomenon occurs when the shield tail passes through the cutting face due to the influence of the grouting; The cutterhead torque of the shield machine in soft soil areas can be composed of five calculation factors, and the calculation results are in good agreement with the measured values. The larger the opening rate of the shield cutterhead is, the larger the average torque value will be, the higher the percentage of large ground loss rate will be, and the larger the maximum ground surface settlement will be; The ratio of cutterhead torque T to mucking volume per ring Q is used as the control parameter for analyzing the ground surface settlement, and a certain positive correlation between the ratio and the surface settlement value is determined, the smaller the cutterhead opening rate is, the more accurate the fitting results will be. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
68.
良好的表面防腐涂装对保证岸边起重机金属结构长期安全有效工作十分重要。以氟碳面漆取代聚氨酯面漆,可显著提高漆面的耐久性、耐候性、耐腐蚀性,并具有优异的自清洁性和耐冲刷性。要保证氟碳面漆的优异性能,必须选用合适的树脂原料、颜料、溶剂和助剂,并在涂料的生产和涂装施工过程中严格执行工艺要求。 相似文献
69.
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