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排序方式: 共有1111条查询结果,搜索用时 805 毫秒
971.
基于时间外推的目标跟踪解析算法及其改进* 总被引:1,自引:0,他引:1
为了解决解析算法在解算过程中存在的多解问题,提出一种解的确定方法,通过预测传感器发现目标的时间,给出一种时间递进的解的确定过程。最后,借助于Repast仿真平台,对算法进行了仿真,表明解析算法与线性拟和算法相比,具有更好的精度。 相似文献
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974.
通过模压工艺制备了酚醛-石英混织纤维增强苯并噁嗪复合材料(P-Q/BZ)试样,考察了其力学性能、烧蚀性能和耐冲刷性能,分析了该试样在高温环境中的主要失效特征,研究其在高温环境中的适用性。结果表明,未经热处理的P-Q/BZ试样平均弯曲强度、弯曲模量和层间剪切强度分别为283 MPa、10.8 GPa和22.6 MPa;经300℃,N_2处理15 min后,试样均匀膨胀,厚度增加22%,弯曲强度、弯曲模量和层间剪切强度分别下降58%、41%和58%;在氧乙炔焰的平均质量烧蚀率和线烧蚀率分别为0.048 4 g/s和-0.081 mm/s,烧蚀后试样宏观不分层,表面炭层微观分层严重,酚醛纤维热解炭、树脂基体热解炭、熔融石英纤维以及碳硅氧化产物相互分离;该试样耐冲刷能力差,在发动机尾焰烧蚀平台模拟的热-力耦合环境中的质量损失率高达59%。P-Q/BZ复合材料需要解决热解膨胀问题,进一步提高抗冲刷性能。 相似文献
975.
《防务技术》2020,16(5):1062-1072
Recent years have seen an explosion in graph data from a variety of scientific, social and technological fields. From these fields, emotion recognition is an interesting research area because it finds many applications in real life such as in effective social robotics to increase the interactivity of the robot with human, driver safety during driving, pain monitoring during surgery etc. A novel facial emotion recognition based on graph mining has been proposed in this paper to make a paradigm shift in the way of representing the face region, where the face region is represented as a graph of nodes and edges and the gSpan frequent sub-graphs mining algorithm is used to find the frequent sub-structures in the graph database of each emotion. To reduce the number of generated sub-graphs, overlap ratio metric is utilized for this purpose. After encoding the final selected sub-graphs, binary classification is then applied to classify the emotion of the queried input facial image using six levels of classification. Binary cat swarm intelligence is applied within each level of classification to select proper sub-graphs that give the highest accuracy in that level. Different experiments have been conducted using Surrey Audio-Visual Expressed Emotion (SAVEE) database and the final system accuracy was 90.00%. The results show significant accuracy improvements (about 2%) by the proposed system in comparison to current published works in SAVEE database. 相似文献
976.
二次型极小化问题的迭代算法 总被引:1,自引:1,他引:0
在新的控制条件下,证明了二次型极小化问题的迭代算法的有效性,所得结果改进了徐洪坤关于二次型优化的最新结果。 相似文献
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978.
一种改进的板块元目标回声计算方法 总被引:3,自引:1,他引:2
板块元法是一种水下目标回声特性的近似计算方法,提高其积分计算的稳定性和快速性是应用中常遇到的问题。将Gordon积分算法引入到板块元方法中,并结合面元声散射特点,对其加以简化。仿真结果表明,所提方法在计算目标回声中不仅有效克服了常规算法中的不稳定问题,也使计算速度得以提高。 相似文献
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980.
Sandor Fabian 《Defense & Security Analysis》2019,35(3):308-325
Following Russia’s annexation of Crimea and its initial actions in eastern Ukraine in 2014, the term hybrid warfare has received much public attention. Many have argued that the Russian actions we saw in Ukraine were part of a completely new strategy while others have suggested that there was nothing new in Russia’s actions. This article takes a critical look at these claims. Through the assessment of the history of the term hybrid warfare and a rigorous analysis of the so-called Gerasimov doctrine, this study finds that the Russian hybrid warfare strategy is rather a western myth than a formal comprehensive Russian strategic concept. Additionally, through the assessment of the Russian use of information operations and the way she has utilised the cyberspace in several recent conflicts, the study finds that against all claims Russia did not make these areas its main battlefield, but rather has been using them in support of its traditional concepts. 相似文献