• 제목/요약/키워드: BIG KINDS

검색결과 305건 처리시간 0.031초

임베디드 OS를 적용한 전력용 디지털 장치의 개발 (A Development of Intelligent Electronic Device(IED) for Electric Power System applied embedded OS)

  • 오재훈;권효철;오성민;홍정기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.936-937
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    • 2008
  • As a micro computer or micro processor technology has been advanced, the essential part which consists of electric power system has been changed into intelligent electronic device(IED), that is one kind of embedded system. There are already many parts changed into digital from analog in control and maintenance devices of electric system. These trends make advanced and novel concepts of devices and systems, that we couldn't even imagine in the analog circumstances. Now, the rate's of change is comparatively slower than IT field that is mainly represented by mobile communication, but that is a big change in the history of electric industries. Some people in those field called it Power-IT, and there have been many kinds of researches. Accelerated systems to go digital, users always and continuously demand more convenient, practical, and new functions. So, a lot of electric system manufactures have had tasks realizing many kinds of functions in an electronic device. According to the high-end technologies in semi-conductor and micro-computer field, manufactures can fully satisfy almost all of customer's needs, but there are other kinds of problems, such as large amount of program code, increasing complexity in proportion with program amount, and the hardness of maintenance and revision of the program. So nowadays, the necessity of embedded OS was emerged as a solution, and many researchers and manufactures have concentrated on studies related to embedded OS and its application.

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A Study of Stage Costume of Peking Opera

  • Lee, Young-Suk
    • The International Journal of Costume Culture
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    • 제6권1호
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    • pp.38-51
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    • 2003
  • Peking Opera, one of a representative Chinese dramas, is a synthesis of drama and stage art. Peking Opera's stage costume was set up in Qing dynasty though its style was embellished with mainly Ming dynasty's clothing style. The special patterns in the clothing were very important because they classified social rankings. There are two kinds of roles in Peking Opera. Sheng stands for male roles and Dan stands for female roles though Dan had traditionally been acted by male actors with female attire until the ruling of the People's Republic of China. There are five different kinds Peking Opera's stage costume. First, Mang is a formal dress for kings and generals. It is a very delicate long Po with special patterns. It has several names depending on the color and shape of a dragon. Second, Pee is a casual attire for kings, government officials, and their families. It is also a long Po with front opening and symmetrical neckline. Third, Kao is an armor of warrior which is made not for protection in a real war but for ornament of a formal dress. Kao reflects the wearer's authority when the wearer stays still, but it is a comfortable clothing for big dancing moves once the wearer starts dancing. The wearer puts a banner into the shoulder to alarm tension of a war. Fourth, Cheup is an outfit that one wears the left part adjust to the top. There are different lengths of Cheup and it has a straight neckline. There are twenty-one different kinds of Cheup according to its shape and color. Last, Yi is name for the rest of Peking Opera's stage costume other than Mang, Pee, Kao, and Cheup.

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발전 설비 지속 가능 운영 기술 연구 (A Study of the Sustainable Operation Technologies in the Power Plant Facilities)

  • 이창열;박길주;김태환;구영현;이성일
    • 한국재난정보학회 논문집
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    • 제16권4호
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    • pp.842-848
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    • 2020
  • 연구목적: 노후화된 발전기의 지속 가능한 운영을 위하여 효율적이며, 안전한 운영이 중요하다. 효율적 운영이란 경제적 관점이며, 안전한 운영은 발전 설비의 치명적 사고 발생에 대한 발생 이전의 사전 조치를 말한다. 그러므로 발전기의 지속가능 운영 모니터링을 위하여 관련된 센서 설치와 이를 기반으로 지속 가능에 대한 예측할 수 있는 모델에 대한 연구가 필요하다. 연구방법: 전기와 열에 대한 수요 예측, 엔진의 성능과 이상을 탐지하는 예측, 그리고 재 난 안전에 대한 예측 모델을 제시하였다. 이를 위하여 필요한 센서를 정의하였으며, 이를 기반으로 예측 모델을 각각 개발하여 수행하였다. 연구결과: 수요 예측 모델은 기존의 79%에서 90% 이상으로 예측 정확도를 향상시켰으며, 다른 2개 모델도 시스템의 지속가능한 안정적 운영을 지원하였다. 결론: 노후화된 발전설비의 지속가능 운영을 지원하기 위한 3가지 종류의 예측 모델을 개발하고 이를 제이비주식회사의 발전 설비에 실제 적용하여 운영하고 있다.

Hot Pressing of the Silicon Nitride Based Ceramics and Their Mechanical Behavior

  • Park, D.S.;Lee, S.Y.;Kim, H.D.;Park, W.S.;D.S. Lim;B.D. Han
    • The Korean Journal of Ceramics
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    • 제1권1호
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    • pp.45-54
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    • 1995
  • Four kinds of silicon nitride based ceramic materials have been hot pressed. Effect of the sintering additives on the phase transformation, microstructural development and mechanical properties was investigated. While sintering under the same condition a big difference among the microstructures of the specimens, they appeared alike if sintered to have a similiar $\alpha$-$\beta$ phase ratio. The specimen of the stoichiometric $\alpha$-$\beta$ sialon composition showed very limited amount of the intergranular glassy phase and a significant degree of the residual stress. It exhibited almost no strength degradation up to $1300^{\circ}C$, and the strength of the specimen degraded more as its composition deviated from the stoichiometry.

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유압 제어계에서 서보밸브 선형화 방정식의 오차 평가 (Error Evaluation of Linearized Equation for a Servovalve in Hydraulic Control Systems)

  • 김태형;이일영
    • 대한기계학회논문집A
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    • 제27권5호
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    • pp.779-788
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    • 2003
  • This study evaluates the approximation errors of the existing linearized equation for a servovalve nonlinear flowrate characteristic. At first, the errors are evaluated on flowrate/pressure characteristics diagrams. Subsequently, they are investigated with time response simulation results for several hydraulic control systems. To enable systematic evaluation of computational error, the authors propose three kinds of equations with restructured forms of the existing linearized equation. As results of the evaluations, it is ascertained that comparatively good computational accuracy can be achieved with the existing linearized equation when both an operating point for the linearized equation and operating range of the hydraulic system stay near the flowrate axis of the flowrate/pressure characteristics diagram. In addition, the results show that comparatively big computational error may occur when operating range of a hydraulic system stay apart from the flowrate axis of the flowrate/pressure characteristics diagram.

지의류 추출염액에 의한 견섬유 염색 (Dyeing of Silk with Lichen Extract)

  • 이전숙;이득영
    • 한국염색가공학회지
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    • 제11권6호
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    • pp.43-50
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    • 1999
  • Lichen had been used as dyestuffs before the discovery of synthetic dyes in Europe and by American Indians. To investigate the dyeability of Korean native lichens, 10 kinds of lichen were collected and colorants were extracted from them by boiling in water and fermenting in ammonia water. Silk fabrics were dyed with lichen extract, then the colour differences of dyed silk fabrics were measured before and after color fastness test. The most part of the lichen extracts(Fc, Hh, Me, Pl, Xm, Pr, Cj, Ld, Ry) dyed silk yellowish or reddish brown. The range of colors were 2.4Y 6.5∼10YR 6/7. Pa extract dyed silk purple(1.25RP 5/6). Color differences of laundered specimen with the silk before laundering were very small, but color of the dyed silks after exposing to light showed big differences with the specimen before exposing to light. The colors of the silks dyed with lichens changed from yellowish or reddish brown to greenish brown by laundering and by exposing to light. But the specimen dyed Pa extract changed from purple to blueish purple by laundering and reddish purple by exposing to light.

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수분조건(水分條件)에 따른 토양(土壤)의 공극분포(孔隙分布) 변화(變化) (Changes of Pore Size Distribution in Soils at Different Water Conditions)

  • 조인상
    • 한국토양비료학회지
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    • 제26권4호
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    • pp.284-288
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    • 1993
  • 토양수분조건에 따른 공극(孔隙) 크기별 분포(分布)의 변화를 구명하기 위하여 Vertisol과 Alfisol을 가지고 수분조건(水分條件)이 각각 0.033MPa, 1.5Mpa 및 건조상태(乾燥狀態)에서 동결건조(凍結乾燥)시켜 수은(水銀) 침투법(浸透法)과 보수력(保水力)으로 공극(孔隙)의 크기별 분포(分布)를 측정(測定)하였다. 수은(水銀) 침투법(浸透法)으로 측정한 공극량은 보수력법(保水力法)보다 대공극량(大孔隙量)이 많았고 냉동건조전(冷凍乾燥前)의 수분조건(水分條件)에 따라서도 공극분포(孔隙分布)는 큰 차이가 있었다.

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Development of Paint-type and Spray-type Electromagnetic Wave Absorbers

  • Song Jae-Man;Kim Dong-Ii;Choi Jeung-Hyun;Jeung Jae-Hyun;Kim Ki-Man
    • Journal of electromagnetic engineering and science
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    • 제5권4호
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    • pp.172-175
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    • 2005
  • Sometimes, it is more convenient to use paint-type and spray-type EM wave absorbers than bulk-type or sheet-type. Thus, in this paper, we prepared paint-type and spry-type EM wave absorbers. The proportion of ferrites to paints, particle size of magnetic material, and kinds of paint should be considered to prepare a superior paint-type EM wave absorber. There is no big gap between spray-type and paint-type in EM wave absorption of EM wave absorbers prepared with same composition.

FINANCIAL MODELS INDUCED FROM AUXILIARY INDICES AND TWITTER DATA

  • Oh, Jae-Pill
    • Korean Journal of Mathematics
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    • 제22권3호
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    • pp.529-552
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    • 2014
  • As we know, some indices and data are strong influence to the price movement of some assets now, but not to another assets and in future. Thus we define some asset models for several time intervals; intraday, weekly, monthly, and yearly asset models. We define these asset models by using Brownian motion with volatility and Poisson process, and several deterministic functions(index function, twitter data function and big-jump simple function etc). In our asset models, these deterministic functions are the positive or negative levels of auxiliary indices, of analyzed data, and for imminent and extreme state(for example, financial shock or the highest popularity in the market). These functions determined by indices, twitter data and shocking news are a kind of one of speciality of our asset models. For reasonableness of our asset models, we introduce several real data, figurers and tables, and simulations. Perhaps from our asset models, for short-term or long-term investment, we can classify and reference many kinds of usual auxiliary indices, information and data.

Analysis of Verification Methodologies Based on a SoC Platform Design

  • Lee, Je-Hoon;Kim, Sang-Choon
    • International Journal of Contents
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    • 제7권1호
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    • pp.23-28
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    • 2011
  • In a SoC (system-on-chip) design, a design complexity is a big bottleneck. In order to overcome the design complexity, platform based design method is widely adopted for designers. Most complex SoCs need a heterogeneous design development environment for hardware and software co-design. In this paper, we discuss about some kinds of verification approaches with platform based design methodology at various abstraction levels of SoC design. We separate the verification process to two steps according to the different levels of verification. We employ a flexible SoC design environment to support simultaneous hardware and software development. We demonstrate the verification strategy of a target SoC design, IEEE 802.11a WLAN SoC.