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21.
万来志 《重庆科技学院学报(社会科学版)》2010,(21)
抗日战争是中华民族历史上的一次大浩劫,中国人民为此承受了太多的痛苦与磨难,特别是对于肩负着国家与民族振兴使命的青年更是如此.分析战时青年的心理变化及原因,指出政府和社会对青年人的心理没有采取恰当的方法进行有效的疏导,提出要总结和吸取历史的经验教训,为我们今天应对大灾难提供借鉴. 相似文献
22.
Effects of Copper Coating on the Crystalline Structure of Fine Barium Titanate Particles 总被引:1,自引:0,他引:1
Xinghua Liu Wan Y. Shih Wei-Heng Shih 《Journal of the American Ceramic Society》1997,80(11):2781-2788
We have investigated the effect of a metal coating—copper—on the tetragonal structure of fine barium titanate (BaTiO3 ) particles. The BaTiO3 particles were synthesized by a sol-gel method and heat treated at temperatures >900°C for various amounts of time before coating. The copper coating was achieved by an electroless coating technique. The transmission electron microscopy micrographs revealed that the coated powder contained fine BaTiO3 particles that were embedded in copper patches. The X-ray diffractometry patterns showed that the copper coating increased the c/a ratio of the fine BaTiO3 particles. For powders that were heat treated at 900°C for 10 h and were initially cubic, the copper coating changed the c/a ratio, from 1 to 1.0034. For powders that were calcined at 900°C for 20 h and were initially tetragonal, the copper coating further enhanced the c/a ratio, from 1.0028 to 1.0043. When the copper-coated BaTiO3 particles were oxidized, the c/a ratio was reduced to a value that was approximately equal to or below that of the uncoated powders. A conductive coating can eliminate the depolarization energy of an insulating polar particle. The fact that the copper coating promoted the polar tetragonal phase but the nonconductive copper-oxide coating did not was consistent with the interpretation that the presence of the cubic phase (nonpolar) in small BaTiO3 particles was caused by the depolarization effect. 相似文献
23.
本文讨论了焊接结构生产技术改造的有关问题,包括总思路及总目标、自动化的基本框架、按低成本自动化的原则设计生产线和关键技术问题的论述。 相似文献
24.
Shaohui Mei Genliang Guan Zhiyong Wang Shuai Wan Mingyi He David Dagan Feng 《Pattern recognition》2015
The rapid growth of video data demands both effective and efficient video summarization methods so that users are empowered to quickly browse and comprehend a large amount of video content. In this paper, we formulate the video summarization task with a novel minimum sparse reconstruction (MSR) problem. That is, the original video sequence can be best reconstructed with as few selected keyframes as possible. Different from the recently proposed convex relaxation based sparse dictionary selection method, our proposed method utilizes the true sparse constraint L0 norm, instead of the relaxed constraint L2,1 norm, such that keyframes are directly selected as a sparse dictionary that can well reconstruct all the video frames. An on-line version is further developed owing to the real-time efficiency of the proposed MSR principle. In addition, a percentage of reconstruction (POR) criterion is proposed to intuitively guide users in obtaining a summary with an appropriate length. Experimental results on two benchmark datasets with various types of videos demonstrate that the proposed methods outperform the state of the art. 相似文献
25.
Image preview is a convenient way to browse large or multiple images on small displays. However, current signal-level image
resampling algorithms may remove many features of interest in the preview image. In this paper, we propose perceptual image
preview which retains more perceptual features such that users can inspect features of interest by viewing the preview image
only and without zooming in. This technology has two components, structure enhancement and perceptual feature visualization.
Structure enhancement enhances the image structure while suppressing subtle details using a gradient modulation method, thus
making the succedent perceptual features more apparent. For perceptual feature visualization, features of interest detected
in the picture is visualized on the structure enhanced preview image. We demonstrate with two examples of most commonly used image quality features, image blur and noise. The effectiveness of the proposed method is validated
by experimental results. 相似文献
26.
个性化、高性能的树形菜单有着广泛的应用。在分析.NET框架的TreeView控件的基础上,总结了基于.NET平台实现个性化树形菜单的基本方法,给出了优化树形菜单数据处理性能的基本策略。 相似文献
27.
本文采用用分子动力学方法研究了双酚A型聚碳酸酯的快速拉伸过程.采用COMPASS力场和NPT系综研究了应力应/变关系、能量/应变关系等.应力-应变曲线的研究结果显示,前"屈服点"和后"屈服点"分别为0.14和0.17,应变≤0.05为"弹性区域".0.14<ε_(xx)<1.05的区域为"塑性区域",ε_(xx)>1.05属于"硬化"区.能量-应力关系的研究结果显示,在应力-应变呈线性关系的"弹性区域",体系的总势能及各势能分量随应变增大发生不规则的波动.为了从能量的角度解释PBC-PC在外部拉伸条件下的应变情况,本文还研究了体系总能量与各能量分项,与应变的关系,对链结构与能量分项的关系进行了讨论. 相似文献
28.
根据货运列车编组调度的基本要求,建立了配流模型。利用编组场待编组车节信息,结合到达场列车的实时信息,设计了信息反馈模型。根据配流模型和反馈模型,对列车进行解体和组编,考虑了军需物资和灾需物资的车辆信息,通过调整模型参数,使得模型继续适用那些由于铁路中断,需要绕行的货运列车。改变了传统算法只考虑局部车组信息,而忽视全局车组信息的弊端。因此,该模型具有灵活性。研究了基本的编组调度算法,使用贪心算法和动态规划算法相结合来求解,并分析了该算法的可行性。 相似文献
29.
Wan Hang Mao Yingzhu Cai Yanpeng Li Ran Feng Jingjie Yang Huixia 《Engineering with Computers》2022,38(4):3169-3184
Engineering with Computers - Aerated flow characterized by complex mass transfer processes with multiple hydraulic properties is a common enviro-hydraulics phenomenon, which have a variety of... 相似文献
30.
Ma Chao Wan Minjie Xu Yunkai Ren Kan Qian Weixian Chen Qian Gu Guohua 《Applied Intelligence》2022,52(3):2785-2800
Applied Intelligence - Infrared target tracking plays an important role in both civil and military fields. The main challenges in designing a robust and high-precision tracker for infrared... 相似文献