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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1753-1764页

作者： taher niknam Electronic and Electrical Department Shiraz University of TechnologyShirazIran

We present a new approach based on honey-bee mating optimization to estimate the state variables in distribution networks including distributed generators. The proposed method considers practical models of electrical equipments such as static var compensators, voltage regulators, and under-load tap changer transformers, which have usually nonlinear and discrete characteristics. The feasibility of the proposed approach is demonstrated by comparison with the methods based on neural networks, ant colony optimization, and genetic algorithms for two test systems, a network with 34-bus radial test feeders and a realistic 80-bus 20 kV network.

关键词： Distributed generators (DGs) State estimation Honey-bee mating optimization (HBMO)

A hybrid evolutionary algorithm for distribution feeder reconfiguration

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Science China(Technological Sciences) 2010年第4期53卷 950-959页

作者： taher niknam Ehsan AZAD FARSANI Electronic and Electrical Department Shiraz University of Technology

This paper presents a new method to reduce the distribution system loss by feeder *** new method combines self-adaptive particle swarm optimization(SAPSO) with shuffled frog-leaping algorithm(SFLA) in an attempt to find the global optimal solutions for the distribution feeder reconfiguration(DFR).In PSO algorithm,appropriate adjustment of the parameters is cumbersome and usually requires a lot of time and ***,a self-adaptive framework is proposed to improve the robustness of *** SAPSO the learning factors of PSO coevolve with the *** is combined with the SAPSO algorithm to improve its *** proposed algorithm is tested on two distribution test *** results of simulation show that the proposed algorithm is very powerful and guarantees to obtain the global optimization in minimum time.

关键词： self-adaptive particle swarm optimization(SAPSO) discrete particle swarm optimization(DPSO) binary particle swarm optimization(BPSO) shuffled frog-leaping algorithm(SFLA) evolutionary algorithms(EA) distribution feeder reconfiguration(DFR)

An efficient hybrid evolutionary optimization algorithm based on PSO and SA for clustering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 512-519页

作者： taher niknam Babak AMIRI Javad OLAMAEI Ali AREFI Electronic and Electrical Engineering Department Shiraz University of TechnologyShirazIran Information Technology Department Islamic Azad University-Fars Science and Research BranchShiraz Iran Technical Engineering Department Islamic Azad University-South Tehran BranchTehran Iran Power Engineering Group Department of Electrical and Computer Engineering Tarbiat Modares UniversityTehran Iran

The K-means algorithm is one of the most popular techniques in clustering. Nevertheless, the performance of the Kmeans algorithm depends highly on initial cluster centers and converges to local minima. This paper proposes a hybrid evolutionary programming based clustering algorithm, called PSO-SA, by combining particle swarm optimization (PSO) and simulated annealing (SA). The basic idea is to search around the global solution by SA and to increase the information exchange among particles using a mutation operator to escape local optima. Three datasets, Iris, Wisconsin Breast Cancer, and Ripley's Glass, have been considered to show the effectiveness of the proposed clustering algorithm in providing optimal clusters. The simulation results show that the PSO-SA clustering algorithm not only has a better response but also converges more quickly than the K-means, PSO, and SA algorithms.

关键词： Simulated annealing (SA) Data clustering Hybrid evolutionary optimization algorithm K-means clustering Parti-cle swarm optimization (PSO)

Stochastic framework for reliability enhancement using optimal feeder reconfiguration

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Journal of Systems Engineering and Electronics 2014年第5期25卷 901-910页

作者： Abdollah Kavousi-Fard taher niknam Mohammad-Reza Akbari-Zadeh Bahram Dehghan Nourabad Mamasani Branch Islamic Azad University Electronic and Electrical Department Shiraz University of Technology

Optimal distribution feeder reconfiguration （DFR） is a valuable and costless approach to increase the load balance, reduce the amount of power losses, and improve the voltage of the buses. In this way, this paper aims to investigate the optimal DFR strategy as a proper tool to improve the reliability of the radial distribution networks. The idea of failure rate reduction is employed to see the effect of feeder current reduction on the reliability of the system more accurately. The objects to be investigated are system average interruption frequency index （SAIFI）, system average interruption duration index （SAIDI）, average energy not supplied （AENS） and total active power losses. The problem is then formulated in a stochastic framework based on the point estimate method （PEM） to handle the uncertainty effects. The feasibility and satisfying performance of the proposed method is examined on a standard IEEE test system.

关键词： reliability enhancement uncertainty distribution systems optimal reconfiguration.

Treatment of moderate to severe keratoconus with 6-mm Intacs SK

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 513-516页

作者： Sasan niknam Mehrdad Shamshiri Seyed Sahabaldin Shahrzad Abbas Alipour Mohammad Bagher Rajabi Mohammad taher Rajabi Cornea Unit Dr Khodadoust Eye HospitalShiraz Iran Department of Ophthalmology Dr. Khodadoust Eye HospitalShiraz Iran Department of Ophthalmology Khalili HospitalShiraz Iran Department of Epidemiology and Statistics Faculty of Nutrition and HealthShiraz Iran Department of Ophthalmology Eye Research Center Farabi Eye Hospital Tehran University of Medical SciencesTehran Iran

·AIM:To evaluate the effect of Intacs SK corneal ring segment implant for treatment of patients with moderate to severe keratoconus, who have clear central cornea and cannot tolerate contact lens. ·METHODS:In this prospective, non-comparative, intervent- ional case series study performed in Dena Hospital, Shiraz, Iran, thirty-seven eyes of thirty-six patients with moderate to severe keratoconus, clear central cornea, and contact lens intolerance were enrolled and underwent Intacs SK corneal ring segment implantation. Preoperatively, uncorrected distance visual acuity (UCDVA), best-corrected distance visual acuity (BCDVA), central corneal thickness(CCT) and average keratometry (Av-K) were measured and compared with post-operative results at one week, one month, three months, and six months. ·RESULTS:Mean preoperative UCDVA and BCDVA were (1.32±0.31) logMAR and (1.07±0.27) logMAR, respectively. Av-K was (52.13±0.39)D, and the CCT was (432±39.5)μm. Post-operative examinations showed a clinically significant improvement in both UCDVA and BCDVA (P <0.001). There was also a significant effect based on the time of assessment on both UCDVA and BCDVA and both parameters had a continuous improvement during the follow-up period. Three months after operation there was a statistical significant reduction of Av-K (P =0.0001), but there were no significant changes in CCT (P =0.149). ·CONCLUSION:Intacs SK corneal ring segment implants seem to be a safe and effective treatment option for patients who have keratoconus, clear central cornea, and contact lens intolerance.

关键词： keratoconus Intacs myopia

移动气泡征在深板层角膜移植术中的应用(英文)

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国际眼科杂志 2011年第3期11卷 388-389页

作者： Sasan niknam Mohammad taher Rajabi V. Vinood Mootha Seyed Sahaboddin Shahrzad Mohammad Bagher Rajabi Dr Kho1atoust眼科医院伊朗设拉子德黑兰医科大学Farabi医院眼科眼科研究中心伊朗德黑兰西南医学院眼科美国德克萨斯州达拉斯市设拉子医科大学眼科伊朗设拉子

我们报道了移动气泡征在深板层角膜移植术(deep anterior lamellar keratoplasty,DALK)中的应用。这一体征见于99%以上的患者。有晶状体的圆锥角膜是DALK最主要的适应证,这一体征对这类患者非常有用。我们认为对手术方法的小改进将帮助... 详细信息

我们报道了移动气泡征在深板层角膜移植术(deep anterior lamellar keratoplasty,DALK)中的应用。这一体征见于99%以上的患者。有晶状体的圆锥角膜是DALK最主要的适应证,这一体征对这类患者非常有用。我们认为对手术方法的小改进将帮助医师缩短此类手术的学习过程,避免前房穿透在手术最后阶段的发生。

关键词：移动气泡征深板层角膜移值术应用