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81.
郑福传 《计算机光盘软件与应用》2011,(4)
自从计算机被应用于交通运输业以来,计算机技术在交通运输规划与管理中就得到了越来越广泛的应用.本文分析了计算机技术在交通运输规划与管理中的应用领域,详细讨论了计算机技术在智能运输系统和道路交通系统仿真中的应用. 相似文献
82.
刘征 《电脑编程技巧与维护》2011,(4):3-4
对软件开发框架模型提出了一种新的构化的分析方法,同时介绍了常用的结构化分析的工具及其更实用情况。 相似文献
83.
浅谈网络安全风险的评估方法 总被引:1,自引:0,他引:1
本文通过分析网络系统风险的概念及评价体系建设原则,针对风险评估的流程进行探讨,并就应注意的几个问题提出几点建议。以期通过本文的阐述为网络管理人员更好地制定安全策略提供有效的技术支持。 相似文献
84.
Bo Li Author Vitae Chun-Hou Zheng Author Vitae Author Vitae 《Pattern recognition》2008,41(12):3813-3821
In this paper an efficient feature extraction method named as locally linear discriminant embedding (LLDE) is proposed for face recognition. It is well known that a point can be linearly reconstructed by its neighbors and the reconstruction weights are under the sum-to-one constraint in the classical locally linear embedding (LLE). So the constrained weights obey an important symmetry: for any particular data point, they are invariant to rotations, rescalings and translations. The latter two are introduced to the proposed method to strengthen the classification ability of the original LLE. The data with different class labels are translated by the corresponding vectors and those belonging to the same class are translated by the same vector. In order to cluster the data with the same label closer, they are also rescaled to some extent. So after translation and rescaling, the discriminability of the data will be improved significantly. The proposed method is compared with some related feature extraction methods such as maximum margin criterion (MMC), as well as other supervised manifold learning-based approaches, for example ensemble unified LLE and linear discriminant analysis (En-ULLELDA), locally linear discriminant analysis (LLDA). Experimental results on Yale and CMU PIE face databases convince us that the proposed method provides a better representation of the class information and obtains much higher recognition accuracies. 相似文献
85.
A residual-based moving block bootstrap procedure for testing the null hypothesis of linear cointegration versus cointegration with threshold effects is proposed. When the regressors and errors of the models are serially and contemporaneously correlated, our test compares favourably with the Sup LM test proposed by Gonzalo and Pitarakis. Indeed, shortcomings of the former motivated the development of our test. The small sample performance of the bootstrap test is investigated by Monte Carlo simulations, and the results show that the test performs better than the Sup LM test. 相似文献
86.
Three fifth grade highly aggressive students participated in a study examining effects of an aggression intervention game. Using single-subject multiple baseline research design, the effect of the game was measured across three domains: attribution of peer intent (cognitive), emotional response (affective) and behavior response (behavioral). The results indicate that, while there were observable individual differences, the game had an immediate impact on attribution of peer behavior across all participants, had a less predictable impact on reported behavioral reactions, and had no discernable impact on reported emotional response. Theoretical and practical implications of the study are discussed. 相似文献
87.
88.
郑思孝 《核技术(英文版)》1994,(2)
ACOMPLEX-TYPEFOCUSSEDMAGNETRONFORSPUTTERING¥ZhengSixiao(郑思孝)(InstituteofNuclearScienceandTechnology,SichuanUniversity,Chengdu... 相似文献
89.
郑跃伟 《上海冶金高等专科学校学报》1995,(2)
由于水的选择性吸收特性,辐射换热中水份波长匹配一直是一个有分歧的问题。文章通过理论与计算论证了这个问题,得出的结论否定了波长匹配的重要性。 相似文献
90.
Zhongzhe Li Yufang Chen Xiaoru Yun Peng Gao Chunman Zheng Peitao Xiao 《Advanced functional materials》2023,33(32):2300502
Lithium metal batteries (LMBs), due to their ultra-high energy density, are attracting tremendous attentions. However, their commercial application is severely impeded by poor safety and unsatisfactory cycling stability, which are induced by lithium dendrites, side reactions, and inferior anodic stability. Electrolytes, as the indispensable and necessary components in lithium metal batteries, play a crucial role in regulating the electrochemical performance of LMBs. Recently, the fluorinated electrolytes are widely investigated in high-performance LMBs. Thus, the design strategies of fluorinated electrolytes are thoroughly summarized, including fluorinated salts, fluorinated solvents, and fluorinated additives in LMBs, and insights of the fluorinated components in suppressing lithium dendrites, improving anodic stability and cycling stability. Finally, an outlook with several design strategies and challenges will be proposed for novel fluorinated electrolytes. 相似文献