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971.
Johan Schubert 《International Journal of Approximate Reasoning》2012,53(2):176-189
We construct alternative frames of discernment from input belief functions. We assume that the core of each belief function is a subset of a so far unconstructed frame of discernment. The alternative frames are constructed as different cross products of unions of different cores. With the frames constructed the belief functions are combined for each alternative frame. The appropriateness of each frame is evaluated in two ways: (i) we measure the aggregated uncertainty (an entropy measure) of the combined belief functions for that frame to find if the belief functions are interacting in interesting ways, (ii) we measure the conflict in Dempster’s rule when combining the belief functions to make sure they do not exhibit too much internal conflict. A small frame typically yields a small aggregated uncertainty but a large conflict, and vice versa. The most appropriate frame of discernment is that which minimizes a probabilistic sum of the conflict and a normalized aggregated uncertainty of all combined belief functions for that frame of discernment. 相似文献
972.
电梯群控调度是一类开放、动态、复杂系统的多目标优化问题.目前应用于群控电梯调度的算法主要有分区算法、基于搜索的算法、基于规则的算法和其他一些自适应的学习算法.但已有方法在顾客平均等待时间等目标上并不能够达到较好的优化性能.本文采用强化学习技术应用到电梯群控调度系统中,使用CMAC神经网络函数估计模块逼近强化学习的值函数,通过Q-学习算法来优化值函数,从而获得优化的电梯群控调度策略.通过仿真实验表明在下行高峰模式下,本文所提出的基于CMAC网络强化学习的群控电梯调度算法,能够有效地减少平均等待时间,提高电梯运行效率. 相似文献
973.
974.
975.
讨论了卫星导航中BOC调制解调的原理和实现方法,并着重研究了接收机的码跟踪技术。首先阐述了BOC信号体制出现的国际背景及信号特点,并介绍了BOC(10,5)信号形式和频谱特性,然后简要介绍了信号调制的方法,最后重点讨论信号解调方法。针对BOC信号多峰结构的自相关特性,分别研究并比较了两种解调方案,最后综合两者特点提出了组合式解调恢复方法。 相似文献
976.
977.
Metalloproteins are a family of proteins characterized by metal ion binding, whereby the presence of these ions confers key catalytic and ligand-binding properties. Due to their ubiquity among biological systems, researchers have made immense efforts to predict the structural and functional roles of metalloproteins. Ultimately, having a comprehensive understanding of metalloproteins will lead to tangible applications, such as designing potent inhibitors in drug discovery. Recently, there has been an acceleration in the number of studies applying machine learning to predict metalloprotein properties, primarily driven by the advent of more sophisticated machine learning algorithms. This review covers how machine learning tools have consolidated and expanded our comprehension of various aspects of metalloproteins (structure, function, stability, ligand-binding interactions, and inhibitors). Future avenues of exploration are also discussed. 相似文献
978.
979.
We formulate binary fragmentation as a discrete stochastic process in which an integer mass k splits into two integer fragments j, , with rate proportional to the fragmentation kernel . We construct the ensemble of all distributions that can form in fixed number of steps from initial mass M and obtain their probabilities in terms of the fragmentation kernel. We obtain its partition function, the mean distribution and its evolution in time, and determine its stability using standard thermodynamic tools. We show that shattering is a phase transition that takes place when the stability conditions of the partition function are violated. We further discuss the close analogy between shattering and gelation, and between fragmentation and aggregation in general. 相似文献
980.