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Sensitivity Analysis of the Power System Considering the Load Power Factor While using Direct Load Control (부하 역률을 고려한 직접부하제어 실행시 계통의 민감도 분석)

  • Chae, Myeong-Suk
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.64 no.4
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    • pp.333-336
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    • 2015
  • Recently, the power load is growing larger and because of the environmental limitation of generation, the expansion of generation facilities are becoming more difficult. For that reason the importance of the demand-side resources come to be higher. One method of the demand-side resource, the DLC Program, has executed, and moreover, the loads which are available to be controlled are increasing. It should be considered of some kinds of power system components such as DLCs, because the fact that using the demand resources will be an important part of the power system. This paper considers the power factor of the load-bus which is shedded in the direct load control program. and then analyze the power system using flow sensitivity and voltage sensitivity. In this paper, we assumed two scenarios through the rank of the load power factor at each bus and to compare and evaluate each case, we used Power World for the simulation.

A Robust Watermarking Technique Using Affine Transform and Cross-Reference Points (어파인 변형과 교차참조점을 이용한 강인한 워터마킹 기법)

  • Lee, Hang-Chan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.3
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    • pp.615-622
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    • 2007
  • In general, Harris detector is commonly used for finding salient points in watermarking systems using feature points. Harris detector is a kind of combined comer and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. In this paper, we have used cross reference points which use not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we find cross reference points and take inverse normalization of these points. Next, we construct a group of triangles using tessellation with inversely normalized cross reference points. The watermarks are affine transformed and transformed-watermarks are embedded into not normalized image but original one. Only locations of watermarks are determined on the normalized image. Therefore, we can reduce data loss of watermark which is caused by inverse normalization. As a result, we can detect watermarks with high correlation after several digital attacks.

The Functional Analysis of Blending Brake Control for Stanrard EMU (표준전동차 혼합제동 기능분석 연구)

  • Lee, Woo-Dong
    • Proceedings of the KIEE Conference
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    • 2008.10b
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    • pp.466-467
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    • 2008
  • There are many new technologies for EMU to secure the facilities' safety/validity and maintenance/economical efficiency and technologic competitiveness. For example, now the EMU is using the blending brake technology with electric brake and pneumatic brake and carrying the various performances such as jerk limitation, variable load and blending brake to stop the motor car safely and efficiently. The blending brake takes important parts in braking the cars and It is used in many fields of urban transit. There were many limitations to carry the performances and certificate whether the performances are acceptable in the system or not, because at that time they didn't take the whole prelieminarly inspection. Now we start applying such new methods, taking the whole inspection prior to the installation by analyzing systems requirements and introducing various system engineering design tools. In this paper, we suggest how to reduce the errors by prelieminarly inspection for the brake facilities using the tools and inspect the needs to analyze the brake facilities' performances.

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Art Deco Style in Postmodern furniture Design (포스트모던 가구에 나타난 아르데코의 양식적 특징에 관한 연구)

  • Kim, Seong-Ah
    • Korean Institute of Interior Design Journal
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    • v.16 no.2 s.61
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    • pp.270-277
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    • 2007
  • Postmodern designers freely used historical motifs as symbolic expressions or ornamentations. Historical references often became a key to express their ideal against modern standardization. Among the historical references, Art Deco style was frequently appreciated by postmodern furniture designers from the 1960s throughout postmodern era. This study is Intended to explore the way of incorporating Art Deco in postmodern furniture design. Rational Italian designers in Anti-design Movement began to adapt historical motifs and Pop, and this spread out throughout to other Postmodern designers. The research explored how Art Deco and postmodern design are related and what the examples of Art Deco revival in the postmodern era we. In this sense the research mainly covered from the exhibition catalogs from the 1960s to 1990s. As a result of stylistic, symbolic, methodological analysis, Art Deco revival in postmodern era was an essential method to express anti-modern characteristics of postmodernism. In postmodern design, Art Deco was one of historical styles that surpass the limitation o( modernism, at the same time decorative style that express the postmodern ideal.

Hybrid Type Superconducting Fault Current Limiter Modeling using EMTP (EMTP를 이용한 Hybrid Type Superconducting Fault Current Limiter)

  • Park, Se-Ho;Rhee, Sang-Bong
    • Proceedings of the KIEE Conference
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    • 2008.11a
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    • pp.172-174
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    • 2008
  • A fault current limitation using fault current limiter(FCL) is very important for power system operation. In recent year, a number of research have been performed and still Progressing about the super conducting fault current limiter(SFCL), To protect the power system effectively from the large fault current, several superconducting fault current limiters proposed. However, there are many problem such as cost, recovery and ac loss. To solve these problems, hybrid superconducting fault current limiter(HSFCL) have been proposed. In this paper, HSFCL are modeled using (Electro Magnetic Transient Program - Restructured Version) EMTP-RV.

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Movement Characteristic Analysis for Unconstrained Sleep Efficiency Analysis Based on the Smartphone (무구속 수면효율 분석을 위한 스마트폰 기반 움직임패턴 특성분석)

  • Kim, Do Yoon;Shin, Hangsik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.7
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    • pp.940-944
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    • 2014
  • In this research, we designed representative motion patterns that possibly occurred in sleep situation and evaluated the feasibility of the smartphone based movement recording technique. For this, we designed 7 motions such as posture change, head movement, arm movement (vertical, horizontal), leg movement and hand movement (flipping, folding). Movement was recorded by using the smartphone and the actimetry device simultaneously for comparing the feasibility of smartphone based recording. As a result of experiment, we found that the smartphone based movement recording well reflects the body movement, however, it shows the limitation in recording the small local movement such as hand motion compared with the reference actimetry device, Actiwatch.

A Combined CPG and GA Based Adaptive Humanoid Walking for Rolling Terrains (굴곡진 지형에 대한 CPG 및 GA 결합 기반 적응적인 휴머노이드 보행 기법)

  • Kyeong, Deokhwan;Seo, Kisung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.5
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    • pp.663-668
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    • 2018
  • A combined CPG (Central Pattern Generator) based foot trajectory and GA (Genetic Algorithm) based joint compensation method is presented for adaptive humanoid walking. In order to increase an adaptability of humanoid walking for rough terrains, the experiment for rolling terrains are introduced. The CPG based foot trajectory method has been successfully applied to basic slops and variable slops, but has a limitation for the rolling terrains. The experiments are conducted in an ODE based Webots simulation environment using humanoid robot Nao to verify a stability of walking for various rolling terrains. The proposed method is compared to the previous CPG foot trajectory technique and shows better performance especially for the cascade rolling terrains.

Music Generation Algorithm based on the Color-Emotional Effect of a Painting (그림의 색채 감정 효과를 기반으로 한 음악 생성 알고리즘)

  • Choi, Hee Ju;Hwang, Jung-Hun;Ryu, Shinhye;Kim, Sangwook
    • Journal of Korea Multimedia Society
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    • v.23 no.6
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    • pp.765-771
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    • 2020
  • To enable AI(artificial intelligence) to realize visual emotions, it attempts to create music centered on color, an element that causes emotions in paintings. Traditional image-based music production studies have a limitation in playing notes that are unrelated to the picture because of the absence of musical elements. In this paper, we propose a new algorithm to set the group of music through the average color of the picture, and to produce music after adding diatonic code progression and deleting sound using median value. And the results obtained through the proposed algorithm were analyzed.

A STUDY ON QUADRATIC CURVES AND GENERALIZED ECCENTRICITY IN POLAR TAXICAB GEOMETRY

  • Kim, Kyung Rok;Park, Hyun Gyu;Ko, Il Seog;Kim, Byung Hak
    • Korean Journal of Mathematics
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    • v.22 no.3
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    • pp.567-581
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    • 2014
  • Over the years, there has been much research conducted on quadratic curves and the set of points with the generalized notion of eccentricity in a plane with metrics such as taxicab distance or Chinese-checker distance. On the other hand, polar taxicab distance has been newly proposed on the polar coordinate system, a type of curvilinear coordinate system, to overcome the limitation of pre-existing metrics in terms of describing curved routes. Previous study has looked into the fundamental properties of this metric. From this point of view, we study the quadratic curves and the set of points with the generalized notion of eccentricity in a plane with polar taxicab distance.

A Study on Library Exemption Relating to Digital Reproduction and Transmission (디지털 복제 및 전송에 관한 도서관 면책 연구)

  • 홍재현
    • Journal of Korean Library and Information Science Society
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    • v.33 no.3
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    • pp.327-358
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    • 2002
  • The study has Proceeded through examining and analyzing related laws and articles on library exemption relating to reproduction and transmission in digital environment. First of all, the study investigates and analyzes in detail the changes and characteristics of the regulation of library exemption in WCT, EU, U.S., Japan, and Australia. After analyzing of the article 28 in current Copyright Act and amended proposal for Copyright Act in Korea, it found the regulation to be inadequate. As a result of the legal analysis, this paper is proposing a revised plan of the article 28 in the Copyright Act of Korea.

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