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IEEE/PES Transmission and Distribution Conference and Exposition: Latin America

作者： R. T. de Souza E. G. da Costa A. C. de Oliveira W. de V. Sousa T. C. M. de Morais Industry Academic Unit Paraiba Federal Institute Brazil Department of Electrical Engineering Campina Grande Federal University Brazil Post-Graduate Program in Electrical Engineering - PPgEE - COPELE - DEE Campina Grande Federal University Brazil Encrgisa Paraiba Brazil

Static resistance measurement of circuit breakers has been a crucial technique to assess the state of contacts, supporting maintenance procedures. However, in many cases, the obtained results do not provide accurate data for correct diagnosis, since the test examines only the main contact. This article discusses the application of the contact dynamic resistance measurement (DRM) in the evaluation of main and arcing contacts. The DRM is a contact resistance test, and the resistance is determined during the opening of contacts, analyzing the main and arcing contacts. The research objective is to get the DRM parameters that can assist in the contacts diagnosis. The obtained results indicate that DRM has presented more qualitative parameters than the static resistance test in the evaluation of contacts. The resistance tests were performed applying a direct current with 300 A of ***.

关键词： Resistance Circuit breakers electrical resistance measurement Current measurement Voltage measurement Contacts Oscilloscopes

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SAPF with two Dc-links and series converters feeding OEW transformers for 3P4W systems

SAPF with two Dc-links and series converters feeding OEW tra...

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Annual Conference of Industrial Electronics Society

作者： Gregory A. de A. Carlos Cursino B. Jacobina Euzeli C. dos Santos Department of Control and Industrial Process Federal Institute of Alagoas (IFAL) Palmeira dos Índios - 57601-220 - Alagoas - Brazil Post-Graduate Program in Electrical Engineering - PPgEE - Copele Federal University of Campina Grande (UFCG) Campina Grande Paraíba Brazil Department of Electrical and Computer Engineering Purdue School of Engineering and Technology (IUPUI) Indiana USA

This paper presents a shunt active power filter (SAPF) topology, based on the concept of a transformer with open-end winding (OEW), for reactive power and harmonic compensations employed in three-phase four wire (3P4W) systems under balanced and unbalanced conditions. The proposed system uses two independent dc-links and two independent converters series connected through transformers. Complete system control, including PWM technique, is developed and a comparison between the proposed SAPF and conventional one is presented as well. Simulation and experimental results are provided to validate the theoretical approach.

关键词： Topology Pulse width modulation Capacitors Voltage control Optimization Harmonic analysis Power system harmonics

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A study on self-configuration in the differential evolution algorithm

A study on self-configuration in the differential evolution ...

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IEEE Symposium on Differential Evolution (SDE)

作者： Rodrigo C. P. Silva Rodolfo A. Lopes Alan R. R. Freitas Frederico G. Guimaraes Department of Electrical and Computer Engineering McGill University Montreal Canada Graduate Program in Electrical Engineering Federal University of Minas Gerais (UFMG) Brazil Department of Computer Science Federal University-of Ouro Preto (UFOP) Brazil Guimarães Department of Electrical Engineering Federal University of Minas Gerais (UFMG) Brazil

ISBN: (纸本)9781479944606

The great development in the area of evolutionary algorithms in recent decades has increased the range of applications of these tools and improved its performance in different fronts. In particular, the Differential Evolution (DE) algorithm has proven to be a simple and efficient optimizer in several contexts. Despite of its success, its performance is closely related to the choice of variation operators and the parameters which control these operators. To increase the robustness of the method and the ease of use for the average user, the pursuit for methods of self-configuration has been increasing as well. There are several methods in the literature for setting parameters and operators. In order to understand the effects of these approaches on the performance of DE, this paper presents a thorough experimental analysis of the main existing paradigms. The results show that simple approaches are able to bring significant improvements to the performance of DE.

关键词： Sociology Statistics Vectors Equations Indexes Educational institutions Electronic mail

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Open-end multi-level six-phase machine drive system with three three-phase DC-link converters

Open-end multi-level six-phase machine drive system with thr...

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Annual Conference of Industrial Electronics Society

作者： A. C. N. Maia C. B. Jacobina N. B. Freitas Post-Graduate Program in Electrical Engineering – PPgEE Federal University of Campina Grande (UFCG) Campina Grande PB Brazil Federal Institute of Alagoas (IFAL) Palmeira dos Indios AL Brazil

A novel multi-level AC six-phase motor drive is developed in this paper. The scheme is based on three conventional 2-level three-phase voltage source inverters (VSIs) supplying the open-end windings of a dual three-phase motor (six-phase induction machine). The proposed inverter is capable of supply the machine with multi-level voltage waveforms. The developed system is compared with the conventional solution and it is demonstrated that the drive system permits to reduce the harmonic distortion of the machine currents, to reduce the total semiconductor losses and to decrease the power processed by converter switches. The system model and the Pulse-Width Modulation (PWM) strategy are presented. The experimental verification was obtained by using IGBTs with dedicated drives and a digital signal processor (DSP) with plug-in boards and sensors.

关键词： Topology Inverters Pulse width modulation Harmonic distortion Switching loss Motor drives Switching frequency

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Gene expression imputation across multiple brain regions provides insights into schizophrenia risk (vol 51, pg 659, 2019)

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NATURE GENETICS 2019年第6期51卷 1068-1068页

作者： Huckins, Laura M. Dobbyn, Amanda Ruderfer, Douglas M. Hoffman, Gabriel Wang, Weiqing Pardinas, Antonio F. Rajagopal, Veera M. Als, Thomas D. Nguyen, Hoang T. Girdhar, Kiran Boocock, James Roussos, Panos Fromer, Menachem Kramer, Robin Domenici, Enrico Gamazon, Eric R. Purcell, Shaun Demontis, Ditte Borglum, Anders D. Walters, James T. R. O'Donovan, Michael C. Sullivan, Patrick Owen, Michael J. Devlin, Bernie Sieberts, Solveig K. Cox, Nancy J. Im, Hae Kyung Sklar, Pamela Stahl, Eli A. Pamela Sklar Division of Psychiatric Genomics Icahn School of Medicine at Mount Sinai New York NY USA Department of Genetics and Genomics Icahn School of Medicine at Mount Sinai New York NY USA Department of Psychiatry Icahn School of Medicine at Mount Sinai New York NY USA Icahn Institute for Genomics and Multiscale Biology Icahn School of Medicine at Mount Sinai New York NY USA Vanderbilt University Medical Center Nashville TN USA MRC Centre for Neuropsychiatric Genetics and Genomics Cardiff University Cardiff UK Department of Biomedicine Aarhus University Aarhus Denmark The Lundbeck Foundation Initiative for Integrative Psychiatric Research iPSYCH Denmark Center for Integrative Sequencing Aarhus University Aarhus Denmark Department of Human Genetics David Geffen School of Medicine University of California Los Angeles Los Angeles CA USA Human Brain Collection Core National Institute of Mental Health Bethesda MD USA Laboratory of Neurogenomic Biomarkers Centre for Integrative Biology (CIBIO) University of Trento Trento Italy Clare Hall University of Cambridge Cambridge UK University of North Carolina at Chapel Hill Chapel Hill NC USA Karolinska Institutet Stockholm Sweden Department of Psychiatry University of Pittsburgh Pittsburgh PA USA Systems Biology Sage Bionetworks Seattle WA USA Section of Genetic Medicine Department of Medicine University of Chicago Chicago IL USA Integrated Technology Research Laboratories Pharmaceutical Research Division Takeda Pharmaceutical Company Limited Fujisawa Japan Neuropsychiatry Section Department of Psychiatry Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Neuropsychiatric Signaling Program Department of Psychiatry Perelman School of Medicine University of Pennsylvania Philadelphia PA USA Psychiatry JJ Peters Virginia Medical Center Bronx NY USA Department of Neuroscience Icahn School of Medicine at Mount Sinai New York New York NY USA Friedman Brain Institute

Transcriptomic imputation approaches combine eQTL reference panels with large-scale genotype data in order to test associations between disease and gene expression. These genic associations could elucidate signals in complex genome-wide association study (GWAS) loci and may disentangle the role of different tissues in disease development. We used the largest eQTL reference panel for the dorso-lateral prefrontal cortex (DLPFC) to create a set of gene expression predictors and demonstrate their utility. We applied DLPFC and 12 GTEx-brain predictors to 40,299 schizophrenia cases and 65,264 matched controls for a large transcriptomic imputation study of schizophrenia. We identified 413 genic associations across 13 brain regions. Stepwise conditioning identified 67 non-MHC genes, of which 14 did not fall within previous GWAS loci. We identified 36 significantly enriched pathways, including hexosaminidase-A deficiency, and multiple porphyric disorder pathways. We investigated developmental expression patterns among the 67 non-MHC genes and identified specific groups of pre- and postnatal expression.

关键词： Gene expression Genome-wide association studies Schizophrenia Transcriptomics

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One and Two Dc-Links Universal Active Power Filter Without Series Isolation Transformer

One and Two Dc-Links Universal Active Power Filter Without S...

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IEEE Energy Conversion Congress and Exposition

作者： P. L. S. Rodrigues C. B. Jacobina G. A. de A. Carlos M. B. R. Correa M. A. Vitorino Post-Graduate Program in Electrical Engineering - PPgEE - Copele Federal University of Campina Grande (UFCG) Campina Grande - 58429-900 - Paraiba - Brazil Department of Electrical Engineering Federal University of Campina Grande (UFCG) Campina Grande - 58429-900 - Paraiba - Brazil

ISBN: (纸本)9781479957774

This paper presents two universal active power filter (UAPF) configurations for reactive power and harmonic compensation without series isolation transformer. The proposed systems combine both series and shunt compensation, by using converters with one (configuration I) or two (configuration II) dc-links. They are suitable for applications in which size, weight and cost associated with transformers becomes a critical issue. The PWM techniques and complete control of the systems are developed. Simulation and experimental results are shown for validation purposes.

关键词： isolation transformer active power filter power filters shunt compensation harmonic compensation series (mathematics) Reactive power Transformer Converters Universal

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Hybrid Open-End and NPC AC Six-Phase Machine Drive Systems

Hybrid Open-End and NPC AC Six-Phase Machine Drive Systems

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IEEE Energy Conversion Congress and Exposition

作者： Victor F. M. B. Melo Cursino B. Jacobina Nady Rocha Post-Graduate Program in Electrical Engineering - PPgEE - COPELE - UFCG Campina Grande Paraiba Brazil Electrical Engineering Department - Federal University of Campina Grande - UFCG Campina Grande Paraiba Brazil Federal University of Paraiba - UFPB Joao Pessoa Paraiba Brazil

ISBN: (纸本)9781479957774

This paper presents two machine drive system based on a six-phase machine (SPM) and three-leg converters. The machine is composed of two three-phase groups. For the first configuration, one of the groups is connected to a three-leg converter and the other is connected to other two three-leg converters in an open-end winding configuration (see Fig. 4). For the second configuration, one of the groups is connected to a three-leg converter (similar to first one) and the other group is connected to a three-level NPC converter (see Fig. 5). Since the machine two groups are fed differently, the system topology is considered to be hybrid. The purpose of these topologies is to be an alternative configuration, being midway between the conventional six-leg inverter system (see Fig. 1) and the NPC six-leg inverter system (see Fig. 2) and Conventional twelve-leg Open-end inverter system (see Fig. 3). Compared with the conventional six-leg system, the proposed systems permits reducing the power processed by the semiconductor switches and their ratings, the dc-link voltage and the harmonic distortion. On the other hand, the proposed systems constitute less complex alternatives, compared with the open-end and NPC counterparts (see Fig. 3). PWM and control strategies are discussed. Simulation and experimental results are also presented.

关键词： drive train Figs Thyristors Converters machine six-phase Midway Inventors Harmonic distortion

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AC-DC-AC nine-phase machine drive system based on H-bridges and three-leg converters

AC-DC-AC nine-phase machine drive system based on H-bridges ...

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作者： Melo, Victor F.M.B. Jacobina, Cursino B. Braga-Filho, Edgar R. Cavalcanti, Rodolpho M. De Freitas, Isaac S. Macena, Roberto S. Carlos, Gregory A. De A. Post-Graduate Program in Electrical Engineering - PPgEE COPELE UFCG Brazil Federal University of Campina Grande - UFCG Campiña Grande Paraíba Brazil Federal University of Paraiba - UFPB Joao Pessoa Paraíba Brazil Federal Institute of Technology of Sergipe - IFSE Estancia Sergipe Brazil Federal Institute of Technology of Alagoas - IFAL Palmeira Dos Indios Alagoas Brazil

ISBN: (纸本)9781479940325

This paper presents an ac-dc-ac reversible nine-phase machine drive system. The grid side converter is composed of Y-connected single-phase bridges. As the machine is composed of three three-phase groups, a three-leg converters are connected separately to each group. The topology does not make use of input isolation transformers and reduces the power processed by converter switches when compared to that of conventional two-level converter. Moreover, harmonic distortion in voltages generated by the grid side converter is reduced when compared to conventional two-level converter. The model and the control strategy have been developed. Simulation and experimental results are also presented. © 2014 IEEE.

关键词： Electric inverters

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Investigation on Dynamic Voltage Restorers With Two DC-Links and Series Converters for Three-Phase Four-Wire Systems

Investigation on Dynamic Voltage Restorers With Two DC-Links...

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IEEE Energy Conversion Congress and Exposition

作者： Gregory A. A. Carlos Cursino B. Jacobina Euzeli C. dos Santos Department of Control and Industrial Process Federal Institute of Alagoas (IFAL) Palmeira dos Indios - 57601-220 - Alagoas - Brazil Post-Graduate Program in Electrical Engineering - PPgEE - Copele Department of Electrical Engineering Federal University of Campina Grande (UFCG) Campina Grande - 58429-900 - Paraiba - Brazil Department of Electrical and Computer Engineering Purdue School of Engineering and Technology (IUPI) Indianapolis - 46202-5160 - Indiana - USA

ISBN: (纸本)9781479957774

This paper proposes three dynamic voltage restorer (DVR) topologies. Such configurations are able to compensate voltage sags/swells in three-phase four-wire (3P4W) systems under balanced and unbalanced conditions. The proposed systems in this work use two independent dc-links. The complete control system, including the PWM technique, is developed and comparisons between the proposed configurations and a conventional one are performed. Simulation and experimental results are provided to validate the theoretical approach.

关键词： Vectors Topology Pulse width modulation Switches Inverters Capacitors Insulated gate bipolar transistors

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Automatic stress-relieving music recommendation system based on photoplethysmography-derived heart rate variability analysis

Automatic stress-relieving music recommendation system based...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society

作者： Il-hyung Shin Jaepyeong Cha Gyeong Woo Cheon Choonghee Lee Seung Yup Lee Hyung-Jin Yoon Hee Chan Kim Interdisciplinary Program Biomedical Engineering Major Graduate School Seoul National University Department of Electrical and Computer Engineering Johns Hopkins University Interdisciplinary Program Bioengineering Major Graduate School Seoul National University Department of Biomedical Engineering University of Michigan Department of Biomedical Engineering College of Medicine Seoul National University

ISBN: (纸本)9781424479276

This paper presents an automatic stress-relieving music recommendation system (ASMRS) for individual music listeners. The ASMRS uses a portable, wireless photoplethysmography module with a finger-type sensor, and a program that translates heartbeat signals from the sensor to the stress index. The sympathovagal balance index (SVI) was calculated from heart rate variability to assess the user's stress levels while listening to music. Twenty-two healthy volunteers participated in the experiment. The results have shown that the participants' SVI values are highly correlated with their prespecified music preferences. The sensitivity and specificity of the favorable music classification also improved as the number of music repetitions increased to 20 times. Based on the SVI values, the system automatically recommends favorable music lists to relieve stress for individuals.

关键词： Heart rate variability Stress Recommender systems Indexes Multiple signal classification Educational institutions Music

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