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Van-Tan Tran Tsai-Hsiang Chen 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(11):1612-1619
This study analyzes the wind energy resources on Phuquoc Island, Vietnam. Daily wind data are collected from 2005 to 2011 in this study. The annual mean speed and power density are 6 m/s and 355 W/m2, respectively. Results show that more than 35% of the wind energy comes from the northwest. In this study, a 75 MW wind farm with 25 wind turbines is simulated by using the WAsP 10 program. The wind farm can produce over 189.636 GWh annually. In addition, the effects of wind disturbance and three-phase short circuit of the grid are analyzed using the ETAP 7.0 program. 相似文献
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介绍ET6-VT10型10kV一体化ETA/ETV的原理和特点,及其在110kV沙坪数字化变电站中的应用情况,同时针对其在调试、运行过程中出现的问题,提出了改进措施. 相似文献
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Machine fault prognosis techniques have been profoundly considered in the recent time due to their substantial profit for
reducing unexpected faults or unscheduled maintenance. With those techniques, the working conditions of components, the trending
of fault propagation, and the time-to-failure are precisely forecasted before they reach the failure thresholds. In this work,
we propose the least square regression tree (LSRT) approach, which is an extension of the classification and regression tree
(CART), in association with one-step-ahead prediction of time-series forecasting techniques to predict the future machine
condition. In this technique, the number of available observations is first determined by using Cao’s method and LSRT is employed
as a prediction model in the next step. The proposed approach is evaluated by real data of a low methane compressor. Furthermore,
a comparative study of the predicted results obtained from CART and LSRT are carried out to prove the accuracy. The predicted
results show that LSRT offers the potential for machine condition prognosis.
This paper was recommended for publication in revised form by Associate Editor Eung-Soo Shin
Van Tung Tran is a lecturer at the Hochiminh City University of Technology in Vietnam. He received his B.S. and M.S. degrees in mechanical
engineering from Hochiminh City University of Technology, Vietnam, in 1997 and 2003, respectively, and Ph.D. from Pukyong
National University, South Korea in 2009. His research interests include machine fault diagnosis and condition prognosis.
Bo-Suk Yang is a professor at the Puyong National University in Korea. He received his Ph.D. degree in mechanical engineering from Kobe
University, Japan in 1985. His main research fields cover machine dynamics and vibration engineering, intelligent optimum
design, and condition monitoring and diagnostics in rotating machinery. He has published well over 190 research papers in
the research areas of vibration analysis, intelligent optimum design and diagnosis of rotating machinery. He is listed in
Who’s Who in the World, Who’s Who in Science and Engineering, among others. 相似文献
907.
Yi Zhang Wei‐Hua Zhang Hu Chen Meng‐Long Yang Tai‐Yong Li Ji‐Liu Zhou 《International journal of imaging systems and technology》2013,23(3):249-255
This work presents a novel computed tomography reconstruction method for few‐view problem based on a compound method. To overcome the disadvantages of total variation (TV) minimization method, we use a high‐order norm coupled within TV and the numerical scheme for our method is given. We use the root mean square error as a referee. The numerical experiments demonstrate that our method achieves better performance than existing reconstruction methods, including filtered back projection, expectation maximization, and TV with projection on convex sets. © 2013 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 23, 249–255, 2013 相似文献
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Abstract We consider a planar structure consisting of a linear film and adjacent substrate and cladding having unequal refractive indices and nonlinear coefficients. We show that a new class of waves exists in this structure. We analyse it and present its characteristics. In a symmetric waveguide, some branches reduce to well-known dispersion curves, but there are also unusual degenerate states which can have various applications. 相似文献
910.
Abstract An investigation was carried out to determine the precipitation behavior and strengthening effect in various thermomechanical treatments of Al‐Zn‐Mg alloys containing high Zn and low Mg contents. The results show that the precipitation behavior is largely influenced by a plastic deformation in the thermomechanical treatment, and the final precipitate and dislocation structures are greatly related to the influenced precipitation behavior; hence the strengthening effect is determined. Different alloy contents also cause different influences. A super‐strengthening occurs in the T‐AHA (80°C) treatment attributed to the optimum combination of dislocation and precipitate structure. 相似文献