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991.
楼峰 《网络安全技术与应用》2013,(7):105-106
随着时代的不断进步,计算机网络技术在远程医学、多所医院通过网络相互进行交流和医疗技术上的相互探讨研究上发挥着重要作用。因此,医院对计算机网络技术的要求越来越高。本文重点阐述计算机网络技术如何适应现代医学领域的广泛发展。 相似文献
992.
In new advocated “smart grid” development, an electric load forecaster should possess high-level intelligence in order to handle higher uncertainty, indefiniteness, and variability on electric load demand. The intelligence is referred to as self-learning, self-adaptability, and the highest capability of handling various uncertainties, which the forecaster should possess. In this study, a novel methodology, self-developing and self-adaptive fuzzy neural networks using type-2 fuzzy Bayesian Ying-Yang learning algorithm (SDSA-FNN-T2BYYL) is proposed. Its novelty is that (1) the Bayesian Ying-Yang learning algorithm (BYYL) is used to construct a compact system structure automatically. (2) Further, a novel T2 fuzzy BYYL is presented, which integrates type-2 (T2) fuzzy theory and BYYL in order to achieve two objectives simultaneously: compact system structure and better handling of data uncertainty. (3) Because a training dataset cannot include all possible operation conditions, the system should be able to restructure continuously for good generalization. Consequently, a T2 fuzzy BYY split-and-merge algorithm is proposed. The proposed method is validated using a real operational dataset collected from a Macao electric utility. Simulation and test results reveal that SDSA-FNN-T2BYYL has superior accuracy for load forecasting over other existing relevant techniques. 相似文献
993.
Location information is useful for mobile phones. There exists a dilemma between the relatively high price of GPS devices and the dependence of location information acquisition on GPS for most phones in current stage. To tackle this problem, in this paper, we investigate the position inference of phones without GPS according to Bluetooth connectivity and positions of beacon phones. With the position of GPS-equipped phones as beacons and with the Bluetooth connections between neighbor phones as constraints, we formulate the problem as an optimization problem defined on the Bluetooth network. The solution to this optimization problem is not unique. Heuristic information is employed to improve the performance of the result in the feasible set. Recurrent neural networks are developed to solve the problem distributively in real time. The convergence of the neural network and the solution feasibility to the defined problem are both theoretically proven. The hardware implementation of the proposed neural network is also explored in this paper. Simulations and comparisons with different application backgrounds are considered. The results demonstrate the effectiveness of the proposed method. 相似文献
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Shuai Li Hongzhu Cui Yangming Li Bo Liu Yuesheng Lou 《Neural computing & applications》2013,23(3-4):1051-1060
This paper studies the decentralized control of multiple redundant manipulators for the cooperative task execution problem. Different from existing work with assumptions that all manipulators are accessible to the command signal, we propose in this paper a novel strategy capable of solving the problem even though there exists some manipulators unable to access the command signal directly. The cooperative task execution problem can be formulated as a constrained quadratic programming problem. We start analysis by re-designing the control law proposed in (Li et al. Neurocomputing, 2012), which solves the optimization problem recursively. By replacing the command signal with estimations with neighbor information, the control law becomes to work in the partial command coverage situation. However, the stability and optimality of the new system are not necessarily the same as the original system. We then prove in theory that the system indeed also globally stabilizes to the optimal solution of the constrained quadratic optimization problem. Simulations demonstrate the effectiveness of the proposed method. 相似文献
995.
评估软件安全性常用的方法有风险评估和基于可靠性模型的评估。基于上述二种方法提出了残留风险分级评估方法。该方法用失效强度和失效严重度来刻画软件的风险,较好地解决了由于测试数据按失效严重度分类后数据少而难以应用可靠性模型的问题,并用实例说明了新方法的可行性。 相似文献
996.
为解决(1+λ)进化策略运行时搜索范围优化与优良基因积累之间的矛盾,分析了个体在不同变异率下变异操作后适应度变化情况,提出了一种根据当前最佳个体适应度及种群历史信息动态调整变异率的方法,构造了一个变异率调整函数。在MAT-LAB软件平台上进行了外部进化实验,结果表明,相对于传统的固定变异率方法,该方法不仅减少了所需的演化代数,而且在一定程度上提高了算法的稳定性。 相似文献
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文章介绍了日立Z-5000型原子吸收分光光度计火焰系统和石墨炉系统在日常分析中出现的故障现象和解决方法。 相似文献
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