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介绍了络合物催化剂分子系综设计和构造的理论,二阶非线性光学和量子化学的贡献,及其相关领域的发展概貌,预示了优化光学性质的新结构,有效地指导了络合物催化剂的合成。得到了一些新启示。 相似文献
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介绍了络合物催化剂分子系综设计和构造的理论,二阶非线性光学和量子化学的贡献,及其相关新领域的发展概貌,预示了优化光学性质的新结构,有效地指导了络合物催化剂的合成.得到了一些新启示. 相似文献
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用差分和Monte Carlo求解相结合的方法计算有化学反应的活塞流 总被引:1,自引:0,他引:1
用差分和Monte Carlo求解相结合的方法对有化学反应的标量几率密度函数方程进行了求解,讨论了随机颗粒数和时间步长对计算结果的影响。计算结果表明,当化学反应速率是标量的线性函数时,结果与精确解很吻合;当反应速率满足Arrhenius定律时,结果也是合理的。 相似文献
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根据微正则系综、正则系综、巨正则系综、等温等压系综的概率分布函数推导出各个系综的熵,并且推导出这几种系综的熵可用统一的熵的定义式来表示。 相似文献
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先以熵的定义式推导出微正则系综、正则系综、巨正则系综的概率分布函数,然后由这三种系综的概半分布函数导出系综的熵满足熵的定义式,最后分别探讨这三种系综的热力学性质. 相似文献
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Support vector machines (SVMs) have been introduced as effective methods for solving classification problems. However, due to some limitations in practical applications, their generalization performance is sometimes far from the expected level. Therefore, it is meaningful to study SVM ensemble learning. In this paper, a novel genetic algorithm based ensemble learning method, namely Direct Genetic Ensemble (DGE), is proposed. DGE adopts the predictive accuracy of ensemble as the fitness function and searches a good ensemble from the ensemble space. In essence, DGE is also a selective ensemble learning method because the base classifiers of the ensemble are selected according to the solution of genetic algorithm. In comparison with other ensemble learning methods, DGE works on a higher level and is more direct. Different strategies of constructing diverse base classifiers can be utilized in DGE. Experimental results show that SVM ensembles constructed by DGE can achieve better performance than single SVMs, hagged and boosted SVM ensembles. In addition, some valuable conclusions are obtained. 相似文献
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《科技导报(北京)》2014,(35)
正新型原子滤光器滤波带宽接近原子自然线宽超窄带光学滤光可以有效抑制背景光,同时读取微弱的信号光。激光雷达、大气遥感、激光和量子通信等领域的实践表明,利用吸收、发射及内部能量转换等物理特性的原子滤光是实现超窄带光学滤光的理想方法之一。原子滤光器能够有效地进行频谱滤波,提高光学信号的探测灵敏度。为了探索超窄带光学滤光在基于原子系综的量子存储器、窄带单光子源等领域的新应用, 相似文献