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431.
一种冗余系统诊断策略优化设计算法   总被引:1,自引:0,他引:1       下载免费PDF全文
在冗余系统中,一个测试往往可以检测多个故障的故障单元组合,即故障与测试之间呈现多对一的关系。针对冗余系统故障和测试之间的特殊关系,在前期工作的基础上,提出了一种适用于冗余系统诊断策略优化设计的算法,形成了一个完整的多故障诊断策略的生成方法框架。将此方法应用于某飞机供电系统,可以有效地完成冗余系统故障诊断。  相似文献   
432.
The least-angle strategy is a common wayfinding method that can be applied in unknown environments if the target direction is known. The strategy is based on the navigator's heuristic to select the street segment at an intersection which is most in line with the target direction. To use this strategy, the navigator needs to know the angles between the target direction and the street segments leading out from the intersection. If the direct view to the target is blocked and the target vector cannot be perceived, the target direction that is needed for the decision process is based on the agent's believed position and orientation (estimated through path integration). The agent's believed position and target direction are distorted by human errors in estimation of distances and directions, mainly affecting the path integration process. In this paper we examine how human estimation errors of distance and rotation influence the decision behavior in the wayfinding process in an unknown street environment. To demonstrate the geometrical consequences for a specific test case, we use a simulated software agent which navigates in a simulated street environment.  相似文献   
433.
当今世界范围的竞争日趋激烈,经济的竞争,科学技术的竞争,归根到底是教育的竞争和人才的竞争。因此,提高劳动者的全面素质,对于一个国家的社会经济发展可以说具有决定性的意义。高等职业教育承担着培养一线劳动者的任务,办好高等职业教育,对于全面提高劳动者素质,发展生产力,提高产品质量,促进经济发展具有巨大的作用。本文详细分析并论述了推动高等职业教育发展的措施。  相似文献   
434.
从跨国公司在华投资的现状、历程出发,具体分析跨国公司对华投资战略的特点,并提出减少其负面影响的应对措施。  相似文献   
435.
论现代企业应用性人才需求特征与培养对策   总被引:1,自引:0,他引:1  
本文从企业的角度论述和分析了现代企业对高级应用性人才的需求特征,并提出了培养高级技术应用性人才的若干对策。  相似文献   
436.
《中国航空学报》2016,(1):184-201
A hierarchic optimization strategy based on the offline path planning process and online trajectory planning process is presented to solve the trajectory optimization problem of multiple quad-rotor unmanned aerial vehicles in the collaborative assembling task. Firstly, the path planning process is solved by a novel parallel intelligent optimization algorithm, the central force optimization-genetic algorithm (CFO-GA), which combines the central force optimization (CFO) algorithm with the genetic algorithm (GA). Because of the immaturity of the CFO, the convergence analysis of the CFO is completed by the stability theory of the linear time-variant discrete-time sys-tems. The results show that the parallel CFO-GA algorithm converges faster than the parallel CFO and the central force optimization-sequential quadratic programming (CFO-SQP) algorithm. Then, the trajectory planning problem is established based on the path planning results. In order to limit the range of the attitude angle and guarantee the flight stability, the optimized object is changed from the ordinary six-degree-of-freedom rigid-body dynamic model to the dynamic model with an inner-loop attitude controller. The results show that the trajectory planning process can be solved by the mature SQP algorithm easily. Finally, the discussion and analysis of the real-time per-formance of the hierarchic optimization strategy are presented around the group number of the waypoints and the equal interval time.  相似文献   
437.
围绕航空装备研制过程,结合航空装备行业特点,针对航空装备研制成本监控中存在的问题,探讨了成本监控应对策略。科学开展成本监控,进一步优化装备采购成本,可提高军费使用效益。  相似文献   
438.
The inter-satellite electromagnetic force presents several significant advantages that help to expand its space applications to the multi-satellite missions gradually. For a satellite swarm, whether the electromagnetic force is applied to enable collective maneuver and how to provide a better performance and broader applications for such swarm highlight an important issue. Considering the trajectory planning problem of satellite swarm using inter-satellite electromagnetic force, a behavior-based collective planning scheme is developed by designing the desired velocity of each satellite as the sum of several different behavioral contributions, which are used to represent the internal and external interactions of the swarm. Therefore, the desired configuration is associated with the equilibrium points of the pre-designed kinematical field. Furthermore, the trajectory planning problem could be translated to a parameter optimization problem considering the swarm dynamics with inter-satellite electromagnetic force. Then based on the analysis of the applicability and advantages triggered by integrating the inter-satellite electromagnetic force into such behavior-based planning scheme, the collective trajectory planning problem with sole electromagnetic force actuation and hybrid actuation with thruster are studied respectively. Numerical simulations are carried out to verify the validity of the proposed algorithm, and the satellite swarm performance enhanced by inter-satellite electromagnetic force is discussed at last.  相似文献   
439.
英语作为世界范围内使用最广泛的语言,在各国的航空活动中得到了普遍应用。民航无线电陆空通话英语(简称陆空通话)是按照国际民航组织(ICAO)《无线电通话手册》和《中国民用航空无线电通话手册》为依据而制定的,它是一门特殊的行业英语,是半人造语言。无线电陆空通话英语的语音具有高度清晰性,词汇具有专业性和单一意旨性,句子具有祈使性和省略性的特点。针对这些特点,提出了相应的教学策略:即语境教学法与听说教学法的融合。  相似文献   
440.
结合有限元法,研究了EBE策略在热传导问题并行计算方面的应用,给出了瞬态热传导问题的隐式EBE并行算法。根据所用CPU个数并行计算单元刚度矩阵,而总刚度矩阵K不需要组装,仅在“单元级”上进行各种计算。就模型实验规模1024阶而言,机器存存储量比传统算法降低了40%左右,在拥有共享内存的并行计算机Challenge上的数值实验表明,问题的规模越大,并行效率越高,所给算法非常有效。  相似文献   
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