• 제목/요약/키워드: Electrical and electronic systems

검색결과 2,494건 처리시간 0.029초

Review of Variable-flux Permanent Magnet Machines

  • Owen, R.L.;Zhu, Z.Q.;Wang, J.B.;Stone, D.A.;Urquhart, I.
    • Journal of international Conference on Electrical Machines and Systems
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    • 제1권1호
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    • pp.23-31
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    • 2012
  • Variable-flux permanent-magnet machines (VFPM) are of great interest and many different machine topologies have been documented. This paper categorizes VFPM machine topologies with regard to the method of flux variation and further, in the case of hybrid excited machines with field coils, with regard to the location of the excitation sources. The different VFPM machines are reviewed and compared in terms of their torque density, complexity and their ability to vary the flux.

The Coexistence of OFDM-Based Systems Beyond 3G with Fixed Service Microwave Systems

  • Jo Han-Shin;Yoon Hyun-Goo;Lim Jae-Woo;Chung Woo-Ghee;Yook Jong-Gwan;Park Han-Kyu
    • Journal of Communications and Networks
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    • 제8권2호
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    • pp.187-193
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    • 2006
  • In this paper, we study the coexistence of orthogonal frequency division multiplexing (OFDM)-based systems beyond 3G (B3G) and point-to-point (P-P) fixed service (FS) microwave systems. The advanced general analytical model derived via a power spectral density (PSD) analysis proposed in this paper has two advantages in comparison with the conventional minimum coupling loss (MCL) method. First, the interfering signal power that appears in the band of a victim system can be easily assessed without a spectrum emission mask. Second, when transmit power is not allocated to some subcarriers overlapping the band of the victim system in order to mitigate B3G OFDM-based systems interference with other systems, the general analytical model can successfully assess the interference from the B3G systems into FS systems, whereas the MCL method incorporating the spectrum emission mask cannot be applied in the presence of the same interference condition. The proposed model can be derived in a closed form and is simply implemented with the help of simulation, and thus the solution can be obtained in significantly reduced time. Through application of the proposed model, coexistence results are analyzed in a co-channel and adjacent channel with respect to guard band and minimum separation distance.

자동차 전자파 시험규격 변천사 (A Study on Electromagnetic Standards Changes of Vehicles)

  • 우현구
    • 자동차안전학회지
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    • 제13권2호
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    • pp.7-14
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    • 2021
  • Recently, the amount of electrical and electronic systems is increasing rapidly with the development of advanced vehicles such as ADAS, smart cars, connected cars, automated driving systems. It is necessary to examine the electromagnetic compatibility of vehicles equipped with those systems. The standards and regulations for examination of electromagnetic compatibility have been established and revised according to newly introduced electrical and electronic systems. They are administered in some different international standard associations such as ISO, CISPR, UN/ECE and are somewhat complex and bulky. In the study, the improvements and changes in them are tracked and analyzed chronologically. Research of the history of them will be helpful for understanding progress and forecasting the direction of development.

Document Structure Understanding on Subjects Registration Table

  • Ito, Yuichi;Ohno, Masanaga;Tsuruoka, Shinji;Yoshikawa, Tomohiro;Tsuyoshi, Shinogi
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.571-574
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    • 2003
  • This research is aimed to automate the generating process of the database from paper based table forms like this work. The registration table has so complicate table structures, ana in this research we used the registration tables as an example of general table structure understanding. We propose a table structure understanding system for some table types, and it has some steps. The first step is that the document images on paper are read from the image scanner. The second step is that a document image segments into some tables. In the third step, the character strings is extracted using image processing technology and the property of the character strings is determined. And the structured database is generated automatically. The proposed system consists of two systems. "Master document generation system" is used for the table form definition, and it doesn′t include the handwritten characters. "Structure analysis system for complete d table" is used for the written form, and it analyzes the table form filled in the handwritten character. We implemented the system using MS Visual C++ on Windows, and it can get the correct extraction rate 98% among 51 registration tables written by the different students.

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A Thermal Model for Electrothermal Simulation of Power Modules

  • Meng, Jinlei;Wen, Xuhui;Zhong, Yulin;Qiu, Zhijie
    • Journal of international Conference on Electrical Machines and Systems
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    • 제2권4호
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    • pp.441-446
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    • 2013
  • A thermal model of power modules based on the physical dimension and thermal properties is proposed in this paper. The heat path in the power module is considered as a one-dimensional heat transfer in the model. The method of the parameters extraction for the model is given in the paper. With high speed and accuracy, the thermal model is suit for electrothermal simulation. The proposed model is verified by experimental results.

Mapping of Fine Grayscale Data into the sRGB Color Space

  • Kikuchi, Hisakazu;Sto, Hiroto;Hasebe, Satoshi;Mizutani, Naoki;Muramatsu, Shogo;Sasaki, Shigenobe;Zhou, Zie;Sekine, Seishi;Abe, Yoshito;Nakashizuka, Makoto
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.987-990
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    • 2002
  • Fine grayscale data exceeding 8 bits per pixel is mapped into the sRGB color space so as to be displayed on a 24-bit sRGB CRT monitor. The characteristics of the pseudo gray generated by mapping are investigated in terms of the CIELAB color difference and chromaticities.

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Delta-Operator-Based Digital Redesign of Linear Time-Invariant Systems

  • Lee, Ho-Jae;Park, Jin-Bae;Lee, Yeun-Woo;Joo, Young-Hoon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.942-944
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    • 2004
  • This paper proposes a delta-operator-based digital redesign (DR) technique. An asymptotic property of the delta-operator-based DR is analyzed. The performance recovery is proved as a sampling time approaches zero.

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태양광 시스템의 전 범위 전력점 추종을 위한 CPG 알고리즘에 관한 연구 (A Study on Constant Power Generation Algorithms for a Whole Range Power Point Tracking in Photovoltaic Systems)

  • 양형규;방태호;배선호;박정욱
    • 전력전자학회논문지
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    • 제24권2호
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    • pp.111-119
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    • 2019
  • In this study, constant power generation (CPG) algorithms are introduced for whole range power point tracking in photovoltaic systems. Currently, maximum power point tracking (MPPT) algorithm is widely used for high-power photovoltaic systems. However, MPPT algorithm cannot flexibly control such systems according to changing grid conditions. Maintaining grid stability has become important as the capacity of grid-connected photovoltaic systems is increased. CPG algorithms are required to generate the desired power depending on grid conditions. A grid-connected photovoltaic system is configured, and CPG algorithms are implemented. The performances of the implemented algorithms are compared and analyzed by experimental results.

Method of Controlling Four Sets of Permanent Magnet Synchronous Motor by One Inverter on a Railway Vehicle

  • Ito, Takuma;Inaba, Hiromi;Kishine, Keiji;Nakai, Mitsuki;Ishikura, Keisuke
    • Journal of international Conference on Electrical Machines and Systems
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    • 제3권4호
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    • pp.403-408
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    • 2014
  • If it were possible to control four sets of PMSMs in place of induction motors by using one inverter, we could attain efficient driving trains. In this paper, a method for controlling three sets of PMSMs with one inverter is shown. Additionally, this shows the method to control four sets of PMSMs with one inverter and the results of a simulation with the proposed method.

The Model with the Changing Internal Emotion

  • Ha, Sang-Hyoung;Kim, Seong-Hyun;Kim, Byeong-Kwoan;Kim, Seong-Joo;Jeon, Hong-Tae
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.276-279
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    • 2003
  • Generally, it is known that human beings have both emotion and rationality. Especially, emotion is so subjective that human beings might act in different way for the same environment according to their own emotion. Emotion also plays very important role in communication with someone else. For an agent, even though it is designed to act delicately, when it is designed without internal emotion, it can not interact dynamically just like human beings. In this paper, we suggest an agent which action is effected by not only rationality but also emotion to make it interact with human beings dynamically. It is composed of supervised learning, SOM (Self-Organizing Map) and fuzzy decision.

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