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Optimal capacitor placement in distribution systems solved by the hybrid method of CODEQ (called HCODEQ method) is proposed in this work. The concepts of chaotic search, opposition-based learning, and quantum mechanics are used in the CODEQ method to overcome the drawback of parameters selection in the differential evolution (DE). However, a larger population size must be used in the CODEQ method. That is a drawback for all evolutionary algorithms (EAs). To overcome this drawback, acceleration operation and migrating operation are embedded into the CODEQ method, i.e. HCODEQ method. The use of these two operations can increase the convergence speed without decreasing the diversity among individuals. One benchmark function and various-scale capacitor placement systems are used to compare the performance of the proposed method, CODEQ method, DE, simulated annealing (SA), and ant system (AS). Numerical results show that the performance of the HCODEQ method is better than the other methods. 相似文献
3.
The falling down problem has become one of the very important issues of global public health in an aging society. The specific equipment was adopted as the detection device of falling-down in the early studies, but it is inconvenient for the elderly and difficult for future application. The smart phone more commonly used than the specific fall detection equipment is selected as a mobile device for human fall detection, and a fall detection algorithm is developed for this purpose. What the user has to do is to put the smart phone in his/her thigh pocket for falling down detection. The signals detected by the tri-axial G-sensor are converted into signal vector magnitudes as the basis of detecting a human body in a stalling condition. The Z-axis data sets are captured for identification of human body inclination and the occurrence frequencies at the peak of the area of use are used as the input parameters. A high-level fuzzy Petri net is used for the analysis and the development of identifying human actions, including normal action, exercising, and falling down. The results of this study can be used in the relevant equipments or in the field of home nursing. 相似文献
4.
《Sensors and actuators. B, Chemical》2006,113(1):249-258
Phosphorescence-based optical sensors are typically based on intensity or triplet-lifetime measurements. Lifetime determinations may be performed in the frequency-domain by exciting the luminophor with a sinusoidal modulated light source and measuring the phase shift between the excitation light and the phosphorescence emission. Modulated scattered light at the same frequency of the modulating signal must be removed in order to perform accurate measurements.A new and simple method based on phase-modulation measurements is presented to measure the triplet-lifetime of a long-lifetime phosphorescent luminophor, even if high levels of background short-lived fluorescence or scattered light are present. The method is based on the measurement of the phase shift between excitation and emission light at two different frequencies and it turned to provide reliable lifetime measurements if the background light lifetime is significantly shorter than that of the phosphorescent emission to be measured.Theoretical aspects of the proposed methodology, the design and construction of a fiber-optical measuring system and the selection of the optimal frequencies to perform the accurate lifetime measurements are discussed. Finally, the performance of the proposed measurement method has been assessed in the determination of the triplet-lifetime values of the metal chelate Al-ferron immobilized in an inorganic sol–gel support (an oxygen indicator which displays a strong fluorescence emission overlapping significantly with the measured phosphorescence emission). 相似文献
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Chun Lin Ma Qing Feng Wang Rufen Zhang Jikun Li 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(2):229-235
Six triorganotin(IV) complexes of the type {(R3Sn)2[C3S3(COO)2]}n (R = C6H5 1; n-Bu 2; PhCH2 4; p-F-PhCH2 5; o-F-PhCH2 6) and {(R3Sn)2[C3S3(COO)2]}n·[EtOH] (R = Me 3) have been synthesized by the reaction of bis(carboxymethyl)trithiocarbonate with triorganotin(IV) chloride
in the presence of sodium ethoxide. All complexes were characterized by elemental analysis IR, 1H, 13C and 119Sn NMR spectroscopy. Except for 4–6, all complexes were also characterized by X-ray crystallography. The X-ray date revealed
that complexes 1–3 show two-dimensional network polymeric structure in which the geometries of tin atoms are trigonal bipyramid
with the axial positions occupied by carboxylic oxygen atoms. 相似文献
7.
Iterative computation is pervasive in many applications such as data mining, web ranking, graph analysis, online social network
analysis, and so on. These iterative applications typically involve massive data sets containing millions or billions of data
records. This poses demand of distributed computing frameworks for processing massive data sets on a cluster of machines.
MapReduce is an example of such a framework. However, MapReduce lacks built-in support for iterative process that requires
to parse data sets iteratively. Besides specifying MapReduce jobs, users have to write a driver program that submits a series
of jobs and performs convergence testing at the client. This paper presents iMapReduce, a distributed framework that supports
iterative processing. iMapReduce allows users to specify the iterative computation with the separated map and reduce functions,
and provides the support of automatic iterative processing within a single job. More importantly, iMapReduce significantly
improves the performance of iterative implementations by (1) reducing the overhead of creating new MapReduce jobs repeatedly,
(2) eliminating the shuffling of static data, and (3) allowing asynchronous execution of map tasks. We implement an iMapReduce
prototype based on Apache Hadoop, and show that iMapReduce can achieve up to 5 times speedup over Hadoop for implementing
iterative algorithms. 相似文献
8.
从样本的类空间分布和随机测试样本对每个类别的隶属度两方面考虑,对现有的分离测度进行了改进,并给出了一种基于隶属度分离测度的SVM决策树多类分类算法.实验表明,对于随机测试样本属于每个类别的概率均不相同的多类分类问题,基于隶属度分离测度的SVM决策树在与传统的SVM决策树有着基本相同的分类精度情况下,具有更快的分类速度. 相似文献
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采用真人试穿和主观评价的方法,对9件不同腰位的牛仔裤进行着装实验评价并进行压力舒适性评价.发现所有牛仔裤在穿着的过程中都能满足人体舒适性的要求,其中腰上口位于髋骨上2cm,前中下降1.5cm是最舒适的腰位设计,为合体舒适牛仔裤设计提供技术基础. 相似文献