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151.
Electrically conductive fiber/yarn/fabric is one of the promising materials as flexible conductive sensors because of their sensitivity to strain, temperature and humidity. Aiming at developing of effective flexible sensors, this study investigates experimentally the strain sensing behavior of PPy (polypyrrole)-coated Lycra fibers, showing that the electrically resistance of the conductive fibers changes with the deformation of fibers. The variation in electrically resistance is mainly related to the micro-cracks appearing on the fiber surface during deformation. Then, the effects of the characteristic parameters of the micro-cracks are studied statistically by means of image processing functions in MATLAB, and the governing parameters are determined. Based on the results, a model is built to describe the variation of electrical resistance by the parameters of the micro-cracks. The analytical results are compared with the experimental results, showing an acceptable agreement. 相似文献
152.
Nowadays multi-core processors can be found everywhere. It is well known that one way of improving performance is by parallelization. In this paper we propose a parallelization strategy for Java using algebraic laws. We perform an experiment with two benchmarks and show that our strategy produces a gain similar to a specialized parallel version provided by the Java Grande Benchmark (JGB). 相似文献
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154.
《Particulate Science and Technology》2012,30(8):927-931
ABSTRACTMaterials based on bismuth(III) oxide are candidate to be used in optical and electronic devices because of their properties such as a variable band gap, photoconductivity, photoluminescence, high refractive index, and dielectric permittivity. These properties are dependent of several factors, e.g., present phases and crystal morphology. The microwave-assisted hydrothermal method (MAH) is a fast and efficient approach of synthesis to obtain semiconductor powders. However, the synthesis of monoclinic bismuth oxide (α-Bi2O3) with acicular morphology by MAH was not found in literature. In this paper, microcrystals of acicular α-Bi2O3 (monophasic) were successfully obtained by MAH using a synthesis temperature of 80°C for 0.5?h. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron, and transmission electron microscopies showed the formation of a monoclinic structure (space group P21/c) with acicular morphology that grew along the [001] direction. The temperature and time necessary to synthetize acicular microcrystals were significantly lower than those found for acicular microcrystals obtained by conventional hydrothermal method. 相似文献
155.
The continuous top-t most influential place (CTtMIP)query is defined formally and solved efficiently in this paper.A CTtMIP query continuously monitors the t places with the maximum influence from the ... 相似文献
156.
157.
针对茂名热电厂6号机组检修后燃料量异常波动现象,进行故障分析、故障点现场检查和排除,提出了提高EH油品质的多项措施。 相似文献
158.
Jong-Yul Kim Kyeong-Jun MunHyung-Su Kim June Ho Park 《International Journal of Electrical Power & Energy Systems》2011,33(8):1457-1461
In recent studies, PSO algorithm is applied to solve OPF problem. However, population based optimization method requires higher computing time to find optimal point. This shortcoming is overcome by a straightforward parallelization of PSO algorithm. The developed parallel PSO algorithm is implemented on a PC-cluster system with 8 Intel Pentium IV 2 GHz processors. The proposed approach has been tested on the test systems. The results showed that computing time of parallelized PSO algorithm can be reduced by parallel processing without losing the quality of solution. 相似文献
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