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Implementation of Auto-reclosing Relay Algorithm based on Multi-Agent System using EMTP-MODELS (EMTP-MODELS를 이용한 Multi-Agent System 기반의 자동 재폐로 계전 알고리즘 구현)

  • Lee, Byung-Hyun;Yeo, Sang-Min;Lee, You-Jin;Kim, Chul-Hwan;Sung, No-Kyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.1
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    • pp.8-13
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    • 2008
  • This paper presents auto-reclosing algorithms with reference to power system stability based on MAS(Multi-Agent System). And this paper shows auto-reclosing algorithms considering power system stability. It includes the variable dead time, optimal reclosing, sequential reclosing, emergency extended equal-area criterion(EEEAC) algorithm, and modified EEEAC algorithm. This paper divides Auto-reclosing algorithms into respectively agents according to their tasks. A separated agent is merely a software entity that is situated in some environment and is able to autonomously react to changes in the environment. And all the simulations in this parer were tested by EMTP MODELS.

A Study for Effects of Automatic Transmission Fluid on Fuel Economy (자동변속기유가 연비에 미치는 영향에 대한 연구)

  • Cha SangYeob;Yang SiWon
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2004.11a
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    • pp.117-122
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    • 2004
  • In order to improve the fuel economy by design change of automatic transmission, various technologies such as increased shift stages, slip control of lock-up clutch and compact and low-weight design have been developed. And also many OEMs have developed their own ATFs as a part of these automatic transmissions. In this study. to investigate the effects of ATF characteristics on fuel economy, we got the worldwide OEM ATFs and made some reference fluids. And physical properties, frictional characteristics and fuel economy using dynamometer test for these fluids were evaluated. From the investigation, it was found that viscosities of ATFs are correlated with fuel economy in dynamometer test and reducing the viscosities made it possible to obtain fuel economy.

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A No-Reference Quality Measurement for H.264/AVC Video considering Human Visual System. (시각적 인지 특성을 고려한 H.264/AVC기반 영상의 무기준법 품질측정방법)

  • Kim, Yo-Han;Kim, Hyun-Tai;Park, Jin-Hyun;Shin, Ji-Tae
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.11a
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    • pp.115-118
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    • 2009
  • 영상기술의 발전으로 영상의 품질측정에 관한 연구가 많이 진행되어왔다. 이를 통해 새로운 영상처리, 영상통신등에 사람의 시각적 인지 특성을 고려한 품질측정이 가능해졌다. 무기준법 영상측정방법은 전달된 영상의 정보만을 이용해 품질을 측정하기 때문에, 방송이나 실시간 전송에 주로 이용되어왔다. 이 논문에서 우리는 세가지 비트스트림 정보를 이용한 새로운 무기준법 영상 품질평가 방법을 제안한다. 화면갱신비율, 움직임지수, 양자화계수의 관계를 정립하고, 회기분석을 통해 각각 요소의 가중치를 계산하여냈다. 제안하는 기법을 평가하기 위해, ITU-T P.910에 따라 250개의 영상에 대한 주관적인 영상품질을 측정하였다. 실험결과, 제안하는 화질평가 기법이 기존의 다른 방법들에 비해 주관적인 화질평가와 상관관계가 높게 나타났다.

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Export Performance and Firm Characteristics: Special Reference to Innovation Factors (수출성과와 기업특성: 기술혁신요인을 중심으로)

  • Seong, Tae-Gyeong;Lee, Jong-Min
    • Journal of Korea Technology Innovation Society
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    • v.8 no.1
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    • pp.116-134
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    • 2005
  • This paper investigates the relationships between export and firm characteristics, focusing on technology factors. It is based on a longitudinal data covering listed firms in the Korean manufacturing industry. A regression model for the determinant of export/sales ratio including dynamic adjustment process is tested on a cross-section sample of the year 2001. Empirical findings suggest that there is no significant relationship between export/sales ratio and firm's technological level. The hypotheses concerning human capital intensity and physical capital intensity are also rejected. But we found a positive and inversely U-shaped relationship between firm size and export/sales for basic material and capital good industry. As a dynamic aspect, we found that the pattern of export/sales ratio changed unstably over the last decade. Finally, some policy implications are presented.

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Specific and Sensitive Detection of the Pear Scab Fungus Venturia nashicola by SYBR Green Real-Time PCR

  • Yun, Yeo Hong;Yoon, Seong Kwon;Jung, Jae Sung;Kim, Seong Hwan
    • Journal of Microbiology and Biotechnology
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    • v.25 no.11
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    • pp.1782-1786
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    • 2015
  • A new improved PCR method has been developed for the rapid, reliable, and sensitive detection of Venturia nashicola, a destructive pathogen of scab disease in Japanese pear. The translation elongation factor-1 alpha gene-derived PCR primers specifically amplified a 257-bp-sized DNA band of the target gene from the genomic DNA of V. nashicola. No amplicon was produced from the genomic DNA of other Venturia spp. and reference fungal species tested. With the high detection limit of 10 fg DNA content, our real-time method could be used for the quarantine inspection and field monitoring of V. nashicola.

Comparison of Attitude Estimation Methods for DVL Navigation of a UUV (UUV의 DVL 항법을 위한 자세 추정 방법 비교)

  • Jeong, Seokki;Ko, Nak Yong;Choi, Hyun-Taek
    • The Journal of Korea Robotics Society
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    • v.9 no.4
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    • pp.216-224
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    • 2014
  • This paper compares methods for attitude estimation of a UUV(Unmanned Underwater Vehicle). Attitude estimation plays a key role in underwater navigation using DVL(Doppler Velocity Log). The paper proposes attitude estimation methods using EKF(Extended Kalman Filter), UKF(Unscented Kalman Filter), and CF(Complementary Filter). It derives methods using the measurements from MEMS-AHRS(Microelectromechanical Systems-Attitude Heading Reference System) and DVL. The methods are used for navigation in a test pool and their navigation performance is compared. The results suggest that even if there is no measurement relative to some absolute landmarks, DVL-only navigation can be useful for navigation in a limited time and range.

Parameter Study of Exhaust Pressure in Catalytic Converter (촉매를 고려한 배압 계산에서의 인자 결정 연구)

  • 이원근;임효재
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.5
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    • pp.77-82
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    • 2003
  • A parametric study was conducted on pressure drop in a catalytic converter for automobile. In this work, we proposed a new pressure drop relation which contains the various parameters needed to calculate and got a few results. In a monolith of catalyst, the flow originally turbulent flow changes to laminar flow and thus the pressure drop through the monolith is linearly proportional to the velocity. The exhaust pressure is doubly affected by the increase of mean velocity and length when we decrease the diameter of monolith while the volume keeps constant. Theoretical parameters such as $\alpha$ and $\beta$ are suggested to use as a reference value when there is no a experimental data. Especially in the part load test, these values should be modified to consider the property change of exhaust gas.

Semi-automatic Field Morphing : Polygon-based Vertex Selection and Adaptive Control Line Mapping

  • Kwak, No-Yoon
    • International Journal of Contents
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    • v.3 no.4
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    • pp.15-21
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    • 2007
  • Image morphing deals with the metamorphosis of one image into another. The field morphing depends on the manual work for most of the process, where a user has to designate the control lines. It takes time and requires skills to have fine quality results. It is an object of this paper to propose a method capable of realizing the semi-automation of field morphing using adaptive vertex correspondence based on image segmentation. The adaptive vertex correspondence process efficiently generates a pair of control lines by adaptively selecting reference partial contours based on the number of vertices that are included in the partial contour of the source morphing object and in the partial contour of the destination morphing object, in the pair of the partial contour designated by external control points through user input. The proposed method generates visually fluid morphs and warps with an easy-to-use interface. According to the proposed method, a user can shorten the time to set control lines and even an unskilled user can obtain natural morphing results as he or she designates a small number of external control points.

A Characteristics of Directional Orientation of the Houses in Hangae, Omi, Daksil, Jusil Traditional Villages of Geomantic South-west (형국(形局)이 남서향(南西向)을 향하는 전통마을에서 주택의 방위(方位)적 특성 -한개, 오미, 닭실, 주실마을을 중심으로-)

  • Lee, Hyun-Byung;Kim, Sung-Woo
    • Journal of the Korean Institute of Rural Architecture
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    • v.11 no.3
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    • pp.45-52
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    • 2009
  • This study is about the co-relationship between the directional orientation of the houses and the geometric direction in the Korean traditional villages. The major mountain in the back of the village and the front mountain ranges give the most important influence for the direction of the houses. This paper, therefore, tries to identify how the houses of villages facing South-west direct the orientation. The village, where the natural environment face the South-west village, solves the problem by facing major direction rather than one all direction. All houses observe and respect the circumstance of geomantic surrounding to the extant that almost no houses revise its direction without any geomantic reference. This kind of research let us know the relationship between the natural direction, the direction of geomantic surrounding, and the direction of houses in traditional Korean villages.

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Study on Museum Digital Exhibition Mode and Industrialization of Intangible Cultural Heritage

  • Bai, Jian-Song;Boo, Jong-Chul
    • Journal of information and communication convergence engineering
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    • v.9 no.2
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    • pp.129-134
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    • 2011
  • Nowadays, most of exhibits are material antiquities while the exhibit of intangible cultural heritage is deficient and the form is less advanced which cannot meet the exhibition needs of digital times. This has resulted in insufficient display of intangible heritage's value which may not facilitate inherit and protection of intangible heritage, no other than protection mechanism of forming healthy industrialization. This article has established digital exhibition mode in museum about intangible cultural heritage by analysis on current museum and using mobile communication and augmented reality techniques. Discuss the mode in the layer integrating creative industry and mobile industry and provide practicable reference project of forming the healthy industrialization mechanism for protecting intangible heritage.