检索结果-内蒙古大学图书馆

Theory and characteristics of novel variable reluctance 1X resolver

ELECTRICAL engineering IN JAPAN 1996年第5期116卷 128-137页

作者： Ishizaki, A Takasaki, K Shimomura, S Masaki, K Kitazawa, K Tokyo Denki University The Polytechnic University Tamagawa Seiki Co. Ltd. [?]Graduated in 1948 from the Department of Electrical Engineering Tokyo Institute of Technology and received his Dr. of Eng. degree from the same university. He joined Meidensha Corporation in April 1948. He has engaged in research development and design of rotating machines. He became a General Manager of the First Division at Research Laboratory in 1965 a Plant Manager of Ohsaki Works in 1974 and a Director in 1977. He became a Professor in the Department of Electrical Engineering Nagaoka University of Technology in 1981. He has been a Professor on the Faculty of Engineering Tokyo Denki University since 1990. He is engaged mainly in the analysis of rotating machines using finite element method as well as research on the optimization of the rotating machines and their control as a system. He is a member of IEEE.

Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos theta, where theta represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the afore-mentioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy.

关键词： resolver VR type rotating position detection optimal rotor shape electrical error

来源：评论

学校读者我要写书评

暂无评论

A Hierarchical Clustering Based on Mutual Information Maximization

A Hierarchical Clustering Based on Mutual Information Maximi...

引用

IEEE International Conference on Image Processing

作者： M. Aghagolzadeh H. Soltanian-Zadeh B. Araabi A. Aghagolzadeh Control and Intelligent Processing Center of Excellence Department of Electrical and Computer Engineering University of Tehran Tehran Iran Radiology Image Analysis Laboratory Henry Ford Health System Detroit MI USA Faculty of Electrical and Computer Engineering University of Tabriz Tabriz Iran

Mutual information has been used in many clustering algorithms for measuring general dependencies between random data variables, but its difficulties in computing for small size datasets has limited its efficiency for clustering in many applications. A novel clustering method is proposed which estimates mutual information based on information potential computed pair-wise between data points and without any prior assumptions about cluster density function. The proposed algorithm increases the mutual information in each step in an agglomerative hierarchy scheme. We have shown experimentally that maximizing mutual information between data points and their class labels will lead to an efficient clustering. Experiments done on a variety of artificial and real datasets show the superiority of this algorithm, besides its low computational complexity, in comparison to other information based clustering methods and also some ordinary clustering algorithms.

关键词： Mutual information Clustering algorithms Clustering methods Data mining Data structures Density functional theory Computational complexity Entropy Higher order statistics Probability density function

来源：评论

学校读者我要写书评

暂无评论

Optimal DTC control strategy of DFIG using variable gain PI and hysteresis controllers adjusted by PSO algorithm

Periodica polytechnica Electrical engineering and computer s...

引用

Periodica polytechnica Electrical engineering and computer science 2020年第1期64卷 74-86页

作者： Amer, Mokhtar Miloudi, Abdallah Lakdja, Fatiha Geometry Analysis Control and Applications Laboratory Department of Electrical Engineering Faculty of Technology Dr Tahar Moulay University of Saida P. O. B 138 Ennasr Saida20000 Algeria Intelligent Control and Electrical Power System Laboratory Department of Electrical Engineering Faculty of Technology Dr Tahar Moulay University of Saida P. O. B 138 Ennasr Saida20000 Algeria

This paper presents an optimal Direct Torque control (DTC) strategy for Doubly Fed Induction Generator based wind turbine. The proposed strategy is considered based on Particle Swarm Optimization (PSO) Algorithm. The PSO is found to be robust and fast in solving nonlinear problems. Motivation for application of PSO approach is to overcome the limitation of the conventional controllers design, which cannot guarantee satisfactory control performance when designed by trial and error. In this work PSO algorithm was used to adjust the hysteresis torque and flux comparators bandwidths and to tune the parameters of Variable Gain PI (VGPI) controller designed for Maximum Power Point Tracking (MPPT) speed control of wind turbine to ensure high performance torque control. The optimal control strategy is considered in detail and it is shown that the use of the optimized controllers reduces rotor flux and electromagnetic torque ripples and improves the system dynamic performances. The effectiveness of the proposed direct torque control based on PSO algorithm (optimal DTC) method is illustrated through simulations on 1.5 MW DFIG based wind turbine. Simulation results illustrate the improved performances of optimal DTC compared with the conventional DTC. © 2020 Budapest University of Technology and Economics. All rights reserved.

关键词： Asynchronous generators

来源：评论

学校读者我要写书评

暂无评论

AUTOMATIC BRAIN TUMOR SEGMENTATION USING TISSUE DIFFISIVITY CHARACTERISTICS

AUTOMATIC BRAIN TUMOR SEGMENTATION USING TISSUE DIFFISIVITY ...

引用

IEEE International Symposium on Biomedical Imaging

作者： Azadeh Yazdan-Shahmorad Hesamoddin Jahanian Suresh Patel Hamid Soltanian-Zadeh Radiology Department Henry Ford Health System Medical Image Analysis Laboratory Detroit MI USA Electrical and Computer Engineering Department Wayne State University Detroit MI USA Biomedical Engineering Department University of Michigan Ann Arbor MI USA Control and Intelligent Processing Center of Excellence Electrical and Computer Engineering Department Faculty of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781424406715;1424406714

Water diffusion measurements have been shown to be sensitive to tissue cellular size, extra cellular volume, and membrane permeability. Therefore, diffusion tensor imaging (DTI) by MRI can be used to characterize highly cellular regions of tumors versus acellular regions, distinguishing cystic regions from solid regions. An automatic segmentation method is proposed in this paper based on a multi-phase clustering algorithm to segment the brain tumors in a feature space extracted from DTI images. The algorithm is applied on images of a total of 20 patients with 4 different types of tumors. The tumor region segmentation was 92% accurate based on the segmentation results using anatomical images and 100% accurate based on biopsy results. In general, the segmentation results obtained by the proposed method revealed a strong agreement with the biopsy results and anatomical images, providing support for the accuracy and robustness of the proposed feature space and the segmentation procedure.

关键词： Neoplasms Image segmentation Diffusion tensor imaging Clustering algorithms Biopsy Permeability measurement Volume measurement Size measurement Biomembranes Magnetic resonance imaging

来源：评论

学校读者我要写书评

暂无评论

Medical Data Mining using Particle Swarm Optimization for Temporal Lobe Epilepsy

Medical Data Mining using Particle Swarm Optimization for Te...

引用

Congress on Evolutionary Computation

作者： M. Ghannad-Rezaie H. Soltanain-Zadeh M.-R. Siadat K.V. Elisevich Henry Ford Health System and Wayne State University Detroit MI USA Radiology Image Analysis Laboratory Henry Ford Health System Detroit MI USA Control and Intelligent Processing Center of Excellence School of Electrical and Computer Engineering University of Tehran Tehran Iran Neurosurgery Department Henry Ford Health System Detroit MI USA

In clinical problems, numerous factors are usually involved in a medical syndrome. New advances in medicine provide a broad range of diagnosis methods to cover all aspects of a disease. However, huge amounts of raw information may confuse clinicians and decrease decision accuracy. Computerized knowledge extraction is an active area of research in medical informatics. This paper suggests a new medical data mining approach using an advanced swarm intelligence data mining algorithm. Considering medical knowledge discovery difficulties, this approach addresses common issues such as missing value management and interactive rule extraction. Here, surgery candidate selection in temporal lobe epilepsy is the main target application. However, the general idea can be applied to other medical knowledge discovery problems. Experimental results show noticeable performance improvement in the final rule-set quality while the method is flexible and fast.

关键词： Data mining Particle swarm optimization Temporal lobe Epilepsy Medical diagnostic imaging Biomedical imaging Coronary arteriosclerosis Diseases Surgery Medical services

来源：评论

学校读者我要写书评

暂无评论

Mathematical Methods for Detecting and Localizing Failures in Complex Hardware/Software systems

Mathematical Methods for Detecting and Localizing Failures i...

引用

International Conference on Advanced Computer Information Technologies (ACIT)

作者： Olena Syrotkina Oleksandr Aziukovskyi Iryna Udovyk Oleksii Aleksieiev Serhii Prykhodchenko Leonid Ilyin Department of Software Engineering Dnipro University of Technology Dnipro Ukraine Department of Electric Drive Dnipro University of Technology Dnipro Ukraine Department of System Analysis and Control Dnipro University of Technology Dnipro Ukraine Department of Tourism and Hospitality Lesya Ukrainka Eastern European National University Lutsk Ukraine

ISBN: (数字)9781728167602

ISBN: (纸本)9781728167619

This article addresses the problem of creating and applying methods of automatic failure self-diagnostics in complex hardware/software systems (SCADA systems included). We conducted a review of modern methodologies used for solving problems of this class. A structural-logical model was proposed to describe the system's architecture. We developed a mathematical method for diagnosing failures based on analysing changes in the state of system information flows. This included failure diagnostic criteria for the method we developed. As a result, it allowed us to obtain the analytical functional dependencies for the detection and localization of failures in the system's structural modules. Graphs are presented to illustrate the probability of the system's non-failure versus time-of-failure detection and localization. We obtained logical conclusions about improving the quality of system functions using the methods we developed for automatic failure self-diagnostics.

关键词： Servers SCADA systems Real-time systems Data communication Data models Fault diagnosis

来源：评论

学校读者我要写书评

暂无评论

Hippocampal shape analysis in the Laplace Beltrami feature space for temporal lobe epilepsy diagnosis and lateralization

Hippocampal shape analysis in the Laplace Beltrami feature s...

引用

IEEE International Symposium on Biomedical Imaging

作者： Rosita Shishegar Ziba Gandomkar Hamid Soltaman-Zadeh Seyed Reza Moghadasi Control and Intelligent Processing Centre of Excellence (CIPCE) School of Electrical and Computer Engineering College of Engineering University of Tehran Tehran Iran Radiology Image Analysis Laboratory Henry Ford Health System Detroit MI USA Department of Mathematics Sharif University of Technology Tehran Iran

Shape analysis plays an important role in many medical imaging studies. One of the recent shape analysis methods uses the Laplace Beltrami operator which is also used in this paper for hippocampal shape comparison. We proposed a feature vector which consists of size measures and shape descriptors based on Laplace Beltrami eigenvalues and eigenfunctions. The aforementioned feature space is utilised for automatic differentiating normal subjects from epileptic patients as well as distinguishing epileptic patients with left temporal lobe epilepsy (LTLE) from patients with right temporal lobe epilepsy (RTLE). Achieved results are diagnostic accuracy of 93% with 95% sensitivity and lateralization accuracy of 86%. The results are comparable to spherical harmonic based shape analysis results and notably improved in comparison to volumetric analysis results.

关键词： Shape Temporal lobe Epilepsy Abstracts Indexes Eigenvalues and eigenfunctions Feature extraction

来源：评论

学校读者我要写书评

暂无评论

PID parameters optimization research for hydro turbine governor by an improved fuzzy particle swarm optimization algorithm

引用

Open Electrical and Electronic engineering Journal 2016年 10卷 101-117页

作者： Chen, Gonggui Yangwei, Du Yanyan, Guo Shanwai, Huang Lilan, Liu Key Laboratory of Industrial Wireless Network and Networked Control of Ministry of Education Chongqing University of Posts and Telecommunications Chongqing400065 China Research Center on Complex Power System Analysis and Control Chongqing University of Posts and Telecommunications Chongqing400065 China The Department of Locomotive and Vehicle Engineering Wuhan Railway Vocational College of Technology Wuhan430205 China

Parameter optimization of water turbine regulating system (WTRS) is decisive in providing support for the power quality and stability analysis of power system. In this paper, an improved fuzzy particle swarm optimization (IFPSO) algorithm is proposed and used to solve the optimization problem for WTRS under frequency and load disturbances conditions. The novel algorithm which is based on the standard particle swarm optimization (PSO) algorithm can speed up the convergence speed and improve convergence precision with combination of the fuzzy control thought and the crossover thought in genetic algorithm (GA). The fuzzy control is employed to get better dynamics of balance between global and local search capabilities, and the crossover operator is introduced to enhance the diversity of particles. Two different types of WTRS systems are built and analyzed in the simulation experiments. Furthermore, the sum of regulating time and another number that is the integral of sum for absolute value of system error and the squared governor output signal is considered as the fitness function of this algorithm. The simulation experiments for parameter optimization problem of WTRS system are carried out to confirm the validity and superiority of the proposed IFPSO, as compared to standard PSO, Ziegler Nichols (ZN) algorithm and fuzzy PID algorithm in terms of parameter optimization accuracy and convergence speed. The simulation results reveal that IFPSO significantly improves the dynamic performance of system under all of the running conditions. © Gonggui et al.

关键词： Fuzzy control

来源：评论

学校读者我要写书评

暂无评论

Scalable Designs for Reinforcement Learning-Based Wide-Area Damping control

Scalable Designs for Reinforcement Learning-Based Wide-Area ...

引用

IEEE General Meeting Power& Energy Society

作者： Sayak Mukherjee Aranya Chakrabortty He Bai Atena Darvishi Bruce Fardanesh Optimization and Control Pacific Northwest National Laboratory Department of Electrical and Computer Engineering North Carolina State University School of Mechanical and Aerospace Engineering Oklahoma State University Research &Development New York Power Authority System Planning &Analysis New York Power Authority

ISBN: (数字)9781665408233

ISBN: (纸本)9781665408240

This article discusses how techniques from reinforcement learning (RL) can be exploited to transition to a model-free and scalable wide-area oscillation damping control of power grids. We present two control architectures with distinct features. Performing full-dimensional RL control designs for any practical grid would require an unacceptably long learning time and result in a dense communication architecture. Our designs avoid the curse of dimensionality by employing ideas from model reduction. The first design exploits time-scale separation in the generator electro-mechanical dynamics arising from coherent clustering, and learns a controller using both electro-mechanical and non-electro-mechanical states while compensating for the error in incorporating the latter through the RL loop. The second design presents an output-feedback approach enabled by a neuro-adaptive observer using measurements of only the generator frequencies. The controller exhibits an adaptive behavior that updates the control gains whenever there is a notable change in the loads. Theoretical guarantees for closed-loop stability and performance are provided for both designs. Numerical simulations are shown for the IEEE 68-bus power system model.

关键词： Damping Power system dynamics Reinforcement learning Power system stability Generators Stability analysis Reduced order systems

来源：评论

学校读者我要写书评

暂无评论

Plant-wide performance optimisation - The refrigeration system case

Plant-wide performance optimisation - The refrigeration syst...

引用

IEEE Conference on control Technology and Applications (CCTA)

作者： Torben Green Roozbeh Razavi-Far Roozbeh Izadi-Zamanabadi Henrik Niemann Torben Green and Roozbeh Izadi-Zamanabadi are working at Danfoss A/S Refrigeration and A/C controls Nordborg Denmark postdoc at Department of Control Engineering and System Analysis at Universite Libre De Bruxelles Bruxelles Belgium Department of Electrical Enigeering at Technical University of Denmark Lyngby Denmark

This paper investigates the problem of plant-wide performance optimisation seen from an industrial perspective. The refrigeration system is used as a case study, because it has a distributed control architecture and operates in steady state conditions, which is common for many industrial applications in the process industry. The paper addresses the fact that dynamic performance of the system is important, to ensure optimal changes between different operation conditions. To enable optimisation of the dynamic controller behaviour a method for designing the required excitation signal is presented. Furthermore, invasive weed optimisation is used to find the optimal parameters for local controllers based on the plant wide performance measure.

关键词： Optimization Compressors control systems Steady-state Standards Temperature measurement Delay effects

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：