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71.
着重讨论了AlNiCo、R-Co、Nd-Fe-B及Sm-Fe-N等金属永磁材料的发展与研究现状,对各种合金的性能与应用前景进行了评价。此外,简单介绍了FeCrCo、FeCoV及MnAlC永磁材料。并展望了磁性材料的未来发展趋势。 相似文献
72.
Task allocation strategies for cooperative task planning of multi-autonomous satellite constellation
Feng Yao Jiting Li Yuning Chen Xiaogeng Chu Bang Zhao 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(2):1073-1084
In recent years, the application of imaging satellites has entered a completely new stage, with the new demands such as rapid response to emergency events, observation of large-scale regional targets and multivariate data fusion, the multi-autonomous satellite constellation has been proposed. This paper first designs the structure of multi-autonomous satellite constellation, and a centralized-distributed structure is proposed. This structure could improve the dynamic response capacity of the whole constellation. Then, this paper adds adapted filtering mechanism to single autonomous satellite online scheduling algorithm to enhance its performance. This article also pays more attention on task allocation strategies of the master satellite in constellation, and ten different task allocation strategies based on five dimensions are analyzed by simulation experiments. At last, this paper extracts several characteristic features of the regular observation targets and designs a selector based on support vector machine (SVM). This selector could select an appropriate strategy according to the features of each experiment scenario. 相似文献
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分布式光纤传感器的现状及发展趋势 总被引:1,自引:0,他引:1
介绍了目前分布式光纤传感器的主要研究方法和技术动向,并展望了其发展趋势。 相似文献
78.
飞机整体壁板广义槽分层识别方法及其实现算法(英文) 总被引:5,自引:0,他引:5
To automatically obtain a machining area in numerical control (NC) programming, a data model of generalized pocket is established by analyzing aircraft integral panel characteristics, and a feature recognition approach is proposed. First, by reference to the practical slice-machining process of an aircraft integral panel, both the part and the blank are sliced in the Z-axis direction; hence a feature profile is created according to the slicing planes and the contours are formed by the intersection of the slicing planes with the part and its blank. Second, the auxiliary features of the generalized pocket are also determined based on the face type and the position, to correct the profile of the pocket. Finally, the generalized pocket feature relationship tree is constructed by matching the vertical relationships among the features. Machining feature information produced by using this method can be directly used to calculate the cutter path. The validity and practicability of the method is verified by NC programming for aircraft panels. 相似文献
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