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891.
The study in molecular morphology is given with a highresolution Atomic Force Microscope AFM.IPC-208B.By taking TiN thim film prepared by magnerton sputtering method and polymide(PI) fibre for examples,the preferenthal growing plme of TiN thin film,the atomic arranges of TiN thin film on the preferential growing plme and the surficial micro-structure can be ascertained form the three-dimensional images obtamed by AFM.IPC-208B.These experiments not only identify small structures of the materials,but also affirm that AFM.IPC-208B holds the precision of atomic level and potential application in micro-structure field,at the same time it establishs the groundwork for the application in micro-process kingdom.  相似文献   
892.
EEG spot-recording for clinical patients in the bed is always advocated due to easing patients and making them comfortable. But EEG signals recorded in the ward exposed to various noisesand interference is less effective in the EEG analysis. Atemporal-spatial filter is designed for noise removing of clinical EEG signals, the first filtering is temporal filtering using band-pass filter, and the second filtering is spatial filtering with ICA-based spatial filter. Experimental results indicate that various noises and interferences, such as power interference, blinking, eyes movements, muscle moments, ECG artifacts, etc., are removed effectively, individually or simultaneously.  相似文献   
893.
汽车是人机协同控制的复杂系统,基于NI PXIe8108实时控制器、PXI7842R数据采集卡、模拟驾驶输入设备及相关软硬件搭建了驾驶模拟仿真系统;用LabVIEW编程语言建立了车辆动力学模型;用虚拟引擎Unity3D软件开发了视景系统;并通过数据库技术使仿真过程与视景系统相结合,实现仿真过程与三维动画实时视景系统的数据交互。结果表明:通过人在环路模拟驾驶仿真实验,使仿真过程中引入了驾驶模拟操纵,实现了人在环路的人机交互式仿真,得到汽车相关性能仿真结果,为驾驶过程中人和汽车协同控制仿真和极端工况下的仿真,提供了一种安全、可靠的人车协同控制仿真环境。  相似文献   
894.
The important character of non-magnetic high manganese ZG25 Mn18Cr4 alloy is rapid work-hardening under external stress. With X-ray diffraction and TEM analysis, it is proved that the microstructures of both undeformed and deformed matrixes are austenite and carbide with some striation structure in the matrixes, the amount of stripes in the deformed matrix is obviously more than that in the undeformed matrix. Electronic diffraction analysis confirmed that the stripes in coarse austenite grains are high density lamination fault sheets. A great deal of lamination fault sheets produced by plastic deformation divides up austenite matrix, shortens the free distance of dislocation movement and results in the rapid work-hardening of ZG25Mn18Cr4 alloy.  相似文献   
895.
896.
The monitoring and assessment scheme of the Caiyuanba Yangtze Bridge is present by sensitivity analysis. The mechanics character of the six ties is studied by numerical simulation, and then the sensor location and selection are discussed considering the technique of sensor and construction situation. The trend of the displacement at the sensor location is analyzed according to different damage level of ties, the pattern associating with several displacements which are sensitive to damage at ties is bring forward to improve assessment reliability. The result can assist implement of structural health monitoring system to the same type as this bridge.  相似文献   
897.
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899.
The green is as a symbol of no pollution,no public harm and environmental protection. The green automobile is the inevitable results that the automobile technique continuously developes. A new style vehicle--the green automobile is the urgent solicit of environmental protection is developed. The automobile industry can develop continuously. This article mainly discusses the importance of the green auto_mobile's research and development,the development status in quo and prospect of the green auto_mobile technique in the world,and states the relationship between the green automobile technique and environmental protection from green technical system theoretically clarify the study of green automobile,including its design and the system,the manufacture and its technology,the energy,the rebuild engineering and a series of subjects. How to evaluate the cycle and the evaluable mark of the green automobile,the prospect of green automobile are pointed out.  相似文献   
900.
In TT&C system,unified spread spectrum framework and adaptive antenna digital beamforming technologies are used to track, telemetry and command objects. Constant modulus array (CMA) and adaptive signal canceller estimate the direction of arrival (DOA) of every signal and use the optimum weighted vector to form the beams. The phase weighted vectors estimated from DOA improve the processing gain as well as being utilized in the transmitting of tele command signal to form the beam of specified object. Its processing performance is researched and simulated in this paper.  相似文献   
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