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51.
带平衡约束的矩形布局问题源于卫星舱设备布局设计,属于组合优化问题。深度强化学习利用奖赏机制,通过数据训练实现高性能决策优化。针对布局优化问题,提出一种基于深度强化学习的新算法DAR及其扩展算法IDAR。DAR用指针网络输出定位顺序,再利用定位机制给出布局结果,算法的时间复杂度是O(n3);IDAR算法在DAR的基础上引入迭代机制,算法时间复杂度是O(n4),但能给出更好的结果。测试表明DAR算法具有较好的学习能力,用小型布局问题进行求解训练所获得的模型,能有效应用在大型问题上。在两个大规模典型算例的对照实验中,提出算法分别超出和接近目前最优解,具有时间和质量上的优势。 相似文献
52.
A shaft-loaded blister test has been developed to measure the interfacial energy W of a thin flexible polymeric film adhered to a rigid substrate. A theoretical analysis is given of an axisymmetric debond (blister) in terms of an external applied load P, tensile stretching modulus E and thickness h of the adhering layer. The fracture mechanics model presented considers both elastic and elastoplastic deformations in the thin film. The intrinsic stable interface debonding process provides an attractive alternative to the conventional adhesion measurement techniques. 相似文献
53.
Wen-Bin Chiou Peng-Hui Wan Chin-Sheng Wan 《International journal of human-computer studies》2012,70(2):107-115
Soft lifting refers to the process whereby a legally licensed software program is installed or copied in violation of its licensing agreement. Previous research on this pervasive kind of unethical computer use has mainly focused on the determinants of this unethical act, which are rooted in personal, economic, technological, cultural, socio-political, or legal domains. However, little is known about the symbolic power that soft lifting has on the sense of self. Based on recent advances in behavioral priming, we hypothesized that soft lifting can influence the signals one sends to oneself; more specifically, soft lifting may prime individuals to experience an inauthentic sense of self, which, in turn, prompts further unethical behavior. In Study 1, we showed that participants, primed with the memory of a recent soft lifting experience, cheated more than participants recalling a recent experience of purchasing authentic software or than control participants. Moreover, feelings of inauthenticity mediated the priming effect of soft lifting on dishonest behavior. In Study 2, participants primed with soft lifting showed a greater willingness to purchase a wide range of counterfeit products over authentic products. Besides those antecedents or correlates of soft lifting already identified in the literature, educators should pay more attention to the negative impact of soft lifting on the self-images of users, which may go beyond computer-related behaviors. Priming may provide a new direction for HCI researchers to examine the impact of computer-use-related factors on users' perceptions, motivations, and behaviors. 相似文献
54.
Realistic talking heads have important use in interactive multimedia applications. This paper presents a novel framework to
synthesize realistic facial animations driven by motion capture data using Laplacian deformation. We first capture the facial
expression from a performer, then decompose the motion data into two components: the rigid movement of the head and the change
of the facial expression. By making use of the local-detail preserving property of the Laplacian coordinate, we clone the
captured facial expression onto a neutral 3D facial model using Laplacian deformation. We choose some expression “independent
points” in the facial model as the fixed points when solving the Laplacian deformation equations. Experimental results show
that our approach can synthesize realistic facial expressions in real time while preserving the facial details. We compare
our method with the state-of-the-art facial expression synthesis methods to verify the advantages of our method. Our approach
can be applied in real-time multimedia systems. 相似文献
55.
56.
本文采取问卷调查和文献查阅相结合的方式,对黄冈市卫生专业技术人员队伍现状进行了调查和分析,剖析了黄冈市农村卫生人才培养的方法和经验,提出了切实可行的农村卫生人才培养的对策与建议。 相似文献
57.
万振杰 《计算机光盘软件与应用》2012,(2):163+168
SAR图像处理主要包括相干斑抑制、特征提取等,如果在使用Photoshop插件SAR图像处理图片,将主要精力集中于算法的设计和优化方面,可以尽量减少在用户界面、内存管理和基本的图像操作方面的编程,既可以实现多种图像处理,又容易实现功能的充分扩大与填充,从而在最短的时间内做做多的事。 相似文献
58.
The effect of nitrogen and nickel on the austenite stability and the structural changes as a result of cold work of an Fe-12Cr-23Mn alloy steel has been examined by transmission electron microscopy and X-ray analysis. Prestrain was performed either at room temperature or at 200° C. Final strain was carried out at liquid nitrogen temperature. The volume fraction of strain-induced martensite decreased by 40% and 12% due to the addition of 2.43% Ni and 0.11% N, respectively, despite whether prestrain was performed or not. The mechanisms are discussed in terms of the phase, stacking faults, dislocation cells and dislocation tangles induced by prestrain and final strain. 相似文献
59.
The effect of pre-strain on the strain-induced martensitic transformation of an Fe-12Cr-23Mn austenitic steel has been investigated through transmission electron microscopy and X-ray analysis. Pre-strain was performed either at room temperature or at 200° C. Final strain was carried out at liquid-nitrogen temperature. The phase was shown to form on {1 1 1} planes of the austenite matrix predominantly by overlapping of stacking faults. The martensite transformation sequence was . Nucleation of the phase mainly occurred at intersections of bands. Austenite stability was shown to increase by pre-strain at 25° C or 200° C. Pre-strain at 200° C has a greater effect on austenite stability than does pre-strain at 25° C. The mechanism was discussed in terms of martensite transformation rate and various substructures introduced during straining. Work hardening was shown to depend on the degree of pre-strain and final strain. The correlation between work hardening and substructures introduced during straining was examined. 相似文献
60.
高温钎料PdCu-Ti在氧化铝陶瓷上的润湿性及界面反应 总被引:7,自引:0,他引:7
本文采用座滴法试验研究了合金系统PdCu-Ti在Al2O3上润湿性的变化规律,探讨了界面冶金及结合等行为,运用热力学理论对结果进行了分析,随Ti含量的增加及Pd含量的减少润湿角逐渐降低,Ti的加入使界面发生了一个双重变化;液相侧富氧,钛吸收层的生成及随后的固相侧氧化钛的生成,只有界面上生成一氧化钛,才能有较好的润湿行为和较强的结合力。 相似文献