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121.
Qt/Embedded串口类的设计及应用 总被引:2,自引:0,他引:2
针对Qt/Embedded类中没有提供串口基础类的现状,研究了Qt/Embedded与串口信息交互的方法,并给出了Qt/Embedded串口类的实现及Qt/Embedded串口类在工业控制中的应用实例。 相似文献
122.
Mohammad Biglarbegian Jean W. Zu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2006,44(11):871-885
This article presents a model for solving solid-fluid interactions in vehicles carrying liquids. A tractor-semitrailer model is developed by incorporating suspension systems and tire dynamics. Owing to the solid-fluid interaction, equations of motion for the vehicle system are coupled. To simplify the complicated solution procedure, the coupled equations are solved separately using two different codes. Each code is analyzed separately; but as the parameters of the two codes depend on each other, the codes must be connected at the end of each time step. To determine the dynamic behavior of the system, different braking moments are applied. As the braking moments increase, braking time decreases. However, it turns out that increasing the braking moment to more than a certain level produces no significant results. It is also shown that vehicles carrying fluids need a greater amount of braking moments in comparison to vehicles carrying solids during braking. In addition, as the level of the fluid inside the tanker increases, from one-third to two-third of the tanker's volume, the sloshing forces applied to the tanker's walls increase. It was also concluded that the strategy used in this article to solve for the solid-fluid interaction by incorporating vehicle dynamic effects represents an effective method for determining the dynamic behavior of vehicles carrying fluids in other critical maneuvers. 相似文献
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SONG Zhi-ming KANG Feng-ju TANG Kai and CHU Yan-jun Marine College Northuxstern Polytechnical University Xi'''' an China 《船舶与海洋工程学报》2003,2(2):40-45
Realistic simulation of underwater scene is always difficult because of the special and complex vision effects in underwater space. Seabed is an important part of underwater environment. This paper describes the methods for seabed scene simulation based on OpenGL. It includes construction of fluetuant terrain based on the random sinusoidal algorithm, simulation of seabed flicker effect by means of circular texture mapping and generation of turbidity effect by using fog techniques. For the application based on the leading high level 3D development environment-Vega, underwater scene simulation is still a difficulty since there is no module for it. Based on the analysis of Vega software and the research on seabed scene simulation methods, a Vega extending module named “Underwater Space” was created through developing module class and extending lynx interface. The module class was designed through developing DLL written in C . The Lynx was extended through developing keyword configure file, GUI configure file and lynx plug-in DLL. The problem that Vega can‘t simulate underwater space, is elementarily resolved. The results show that this module is efficient, easy using, and the seabed scene images am vivid. 相似文献
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通过考虑桩土相互作用以及材料和几何非线形,对钢管支架在水平荷栽作用下的极限承载力及其影响因素进行了分析,从而对钢管支架的安全度作出合理的评价。 相似文献
129.
暗挖双连拱隧道穿越浅基础高层楼群区施工技术 总被引:2,自引:1,他引:1
北京城市铁路东直门区间采用双连拱隧道结构形式 ,在富水松散地层中从两栋浅基础高层居民楼中间采用浅埋暗挖法通过 ,施工难度极大。本文主要阐述针对该段复杂的施工边界及约束条件 ,在处理地层与结构、隧道施工与既有建筑物相互作用 ,所采用的技术方法和特殊条件下的高层建筑防护技术 ,以及监测在施工中的应用 ,以期为今后类似工程的施工提供参考和借鉴。 相似文献
130.
考虑流体-桩-土相互作用的独桩平台波浪响应的TMD 控制研究 总被引:2,自引:0,他引:2
采用调谐质量阻尼器对独桩平台的波浪响应进行控制,在对受控结构的波浪响应进行随机振动分析时,考虑了流体-桩土桩互作用的影响,通过一算例具体讨论了TMD的参数对控制效果的影响,计算经表明,适当选择TMD的参数可有效地控制独桩平台的波浪响应,因此TMD在简易平台的振动控制领域有着良好的应用前景。 相似文献