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81.
本文介绍了602所应用CAE技术的现状,并介绍了应用有限元法进行结构分析的经验,和应用先进的CAE技术的体会,指出了工程应用中的不足,展望了CAE技术的应用前景。  相似文献   
82.
Vibrations represent one of the most important topics of the engineering design relevant to flexible structures. The importance of this problem increases when a very flexible system is considered, and this is often the case of space structures. In order to identify the modal characteristics, in terms of natural frequencies and relevant modal parameters, ground tests are performed. However, these parameters could vary due to the operative conditions of the system. In order to continuously monitor the modal characteristics during the satellite lifetime, an operational modal analysis is mandatory. This kind of analysis is usually performed by using classical accelerometers or strain gauges and by properly analyzing the acquired output. In this paper a different approach for the vibrations data acquisition will be performed via image-based technique. In order to simulate a flexible satellite, a free flying platform is used; the problem is furthermore complicated by the fact that the overall system, constituted by a highly rigid bus and very flexible panels, must necessarily be modeled as a multibody system. In the experimental campaign, the camera, placed on the bus, will be used to identify the eigenfrequencies of the vibrating structure; in this case aluminum thin plates simulate very flexible solar panels. The structure is excited by a hammer or studied during a fast attitude maneuver. The results of the experimental activity will be investigated and compared with respect to the numerical simulation obtained via a FEM-multibody software and the relevant results will be proposed and discussed.  相似文献   
83.
声光相关技术在检测宽带微弱信号中有很大的潜力,提出在射频上用声光相关器对扩频信号做相关运算的方案,给出扩频信号的快速捕获、精密跟踪和信息解调的方法,并设计了实验系统,结果得到了验证。  相似文献   
84.
阐述了“先进制造技术与管理”课题的研究背景、研究内容、研究目标及保障措施。拟定的主要研究内容有CAD技术、先进测量技术、先进制造管理技术、新产品开发技术、先进制造经济学。  相似文献   
85.
以乌鲁瓦提水电厂2号发电机组定子绕组为研究对象,对其出现整体下沉的现象进行原因分析、危害分析,确定了定子绕组下沉的处理方法,给出了所需具体的工具、材料,对比了处理前后的试验数据。实践证明,提出的处理方法对其他的定子绕组整体下沉问题的判断和处理具有一定的实践指导意义。  相似文献   
86.
本文通过计划评审技术(PERT)在高机动靶机研制中的成功应用,探讨了如何结合实际情况运用现代工程管理中的一些基本原理,从而达到降谯成本,提高效率的目的.文中对网络计划的时参计算,完工概率分析,静/动态评审提出了见解总结了经验,可供大型科研项目的科学管理作参考。  相似文献   
87.
《中国航空学报》2023,36(4):366-386
In this work, the primary focus is to identify potential technical risks of Artificial Intelligence (AI)-driven operations for the safety monitoring of the air traffic from the perspective of speech communication by studying the representative case and evaluating user experience. The case study is performed to evaluate the AI-driven techniques and applications using objective metrics, in which several risks and technical facts are obtained to direct future research. Considering the safety–critical specificities of the air traffic control system, a comprehensive subjective evaluation is conducted to collect user experience by a well-designed anonymous questionnaire and a face-to-face interview. In this procedure, the potential risks obtained from the case study are confirmed, and the impacts on human working are considered. Both the case study and the evaluation of user experience provide compatible results and conclusions: (A) the proposed solution is promising to improve the traffic safety and reduce the workload by detecting potential risks in advance; (B) the AI-driven techniques and whole diagram are suggested to be enhanced to eliminate the possible distraction to the attention of air traffic controllers. Finally, a variety of strategies and approaches are discussed to explore their capability to advance the proposed solution to industrial practices.  相似文献   
88.
针对运载器电气系统的数字化,给出研制过程中层次的划分、研制的关键环节及相互关系,并对运载器电气系统的数字样机技术和产品全生命周期管理技术进行扼要的分析,最后给出完整的应用系统框架结构。为运载器的数字化研制作了重要的补充。  相似文献   
89.
近年来,美、欧、亚等技术发达国家的政府和工业界正携手研究推广一项叫做CALS(ContinuousAccuisitionandLife-cycleSupport)的工业发展战略措施。CALS主要含义是指:在产品的全寿命过程中,各环节和有关单位综合利用网络、数据库、多媒体等先进信息技术,各种业务和技术信息数字化,并采用统一交换和共享标准,通过网络或其他计算机信息介质,对需要传递共享的技术数据,实现业务和技术数据一次生成,多次传递使用,以此减少重复工作,提高效率。  相似文献   
90.
Due to the long lead time and great expense of traditional sample return mission plans to Mars or other astronomical bodies, there is a need for a new and innovative way to return materials, potentially at a lower cost. The Rapid Impactor Sample Return (RISR) mission is one such proposal. The general mission scenario involves a single pass of Mars, a Martian moon or an asteroid at high speeds (7 km/s), with the sample return vehicle skimming just 1 or 2 m above a high point (such as a top ridge on Olympus Mons on Mars) and releasing an impactor. The impactor strikes the ground, throwing up debris. The debris with roughly the same forward velocity will be captured by the sample return vehicle and returned to Earth. There is no delay or orbit in the vicinity of Mars or the asteroid: RISR is a one-pass mission. This paper discusses some of the details of the proposal. Calculations are presented that address the question of how much material can be recovered with this technique. There are concerns about the effect of Mars tenuous atmosphere. However, it will be noted that such issues do not occur for RISR style missions to Phobos, Deimos, or asteroids and Near Earth Objects (NEOs). Recent test results in the missile defense community (IFTs 6–8 in 2001, 2002) have scored direct hits at better than 1 m accuracy with closing velocities of 7.6 km/s, giving the belief that accuracy and sensing issues are developed to a point that the RISR mission scenario is feasible.  相似文献   
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