• 한국유기농업학회지
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• 제10권1호
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• pp.19-34
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• 2002

This study is to analyze the demand for organic farming products . The demand for organic farming products is increasing rapidly but the study to analyze the demand system by the methods of econometrics is not tried at all because there is no any formal statistical data about the demand. Therefore, this study tries to estimate the raw statistical data to expect the demand trends of organic farming products in the future. To analyze the demand functions of organic farming products such as rice, bean, apple, grape, beef, and park, this study uses AIDS model by using several assumptions and estimates the price and income elasticities of the demands. The results demonstrate that the demands of organic farming products will be increased in the future and the prices of organic farming products will be the key factor in the demand, In 2004, the quantity demanded of the organic grape will account for 3% of total grape market. As a result, consumer's concerns about organic farming products will be high and the demand for organic farming products will be increased. Thus, the reasonable price system has a significant influence on the market of organic farming products.

• 인터넷정보학회논문지
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• 제6권4호
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• pp.1-7
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• 2005

웹 기반 학습시스템은 CGI를 기반으로 하는 절차지향에 따라 구현되었다. 그러나 이러한 방법은 시스템 개발의 경우 프로그램 코드의 중복에 의한 비효율성을 가질 수 있으며, 개발이후에도 운영 및 관리에 어려움을 준다. 따라서 웹 기반 학습시스템에서도 컴포넌트 기반 개발방법의 도입이 필요하다. 본 연구에서는 컴포넌트 합성에 의한 웹 기반 성적처리 시스템을 구현하였다. 적용된 컴포넌트는 Java Beans로 구현하였으며, 합성 방법은 Chiron-2 아키텍처를 이용하였다. 이러한 방법에 의하여 본 연구는 구조적인 장점들뿐만 아니라 유지보수를 측정하는 사이크로매틱 복잡도에서도 낮은 수치를 나타냄으로서 보다 좋은 효율성을 가짐을 알 수 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.49-52
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• 1988

This paper deal with the robust high gain controller design technique by inner-loop feedback, output feedback, feedforward compensation, and presented the algorithm to be required the determination of gain matrix. Using this control scheme, simulation results have bean tested for the linearized model of the aircraft.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.218-221
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• 1999

Magnetization measurements have been carried out on grain aligned Hg-1223 with the applied field parallel to the c-axis. The temperature dependence of the lower critical field H$_{cl}$(T) was determined by considering the effect of the surface barrier on the magnetization. H$_{cl}$(T) have been determined .from magnetic hysteresis loops within the framework of the modified Kim-Anderson critical-state model, where the surface barrier and the lower critical field are explicitly considered. At high temperature, H$_{cl}$(T) is identified as H$_p$(T). This results are agreed with the theory of Bean-Livinston surface barriers.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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• pp.12-12
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• 2010

The hall probe measurement system was used to measure the critical current distribution of superconducting coated conductor. The system consists of reel to reel moving apparatus, 7 array hall probe, a rotary encoder and permanent magnet. The magnetic field profile across the width of superconducting coated conductor using Bean's critical state model was calculated. The effect of various parameters of the formulas on the magnetic field distribution and the effect of shape and size of artificial defects, which were formed on the surface of SmBa2Cu3O7-d(SmBCO) coated conductor using laser marking system, on the hall probe magnetic field signal of the hall probe measurement system was investigated.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.103-106
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• 2000

We have studied the magnetic properties in Bi$_2$Sr$_2$CaCu$_2$O$_8$ single crystal with columnar defects using micro Hall-probe array. We found that fold profiles inside sample were similar to the Bean's critical state model from the magnetic hysteresis measurement. In the magnetic relaxation measurement, the normalized relaxation rates were maximum near the center and decreased toward the edge of the sample expect zero gauss. The relaxation rates as a function of the temperature were maximum near the 40K and rapidly decreased both sides of the peak.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(3)
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• pp.157-160
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• 2002

최근에 인터넷 및 웹의 급속한 발전과 더불어 S/W 개발의 새로운 방법으로 컴포넌트가 대두되고 있다. 이는 빠른 시간 안에 원하는 소프트웨어 제품을 적은 비용과 최소한의 노력으로 생산할 수 있어 효율적인 시스템 개발 및 소프트웨어 재사용에 많은 이점을 가질 수 있다 그러나 현재 사용되고 있는 COM, CORBA등은 프로그램 작성뿐만 아니라, 분산 시스템 하의 서로 다른 플랫폼에서 운영상의 문제점들이 발생하게 되었다. 본 논문에서 제시한 EJB 방식의 아키텍쳐 시스템은 서로 다른 네트워크 환경과 이기종의 시스템에 존재하는 프로그램 객체들을 동일 시스템에서 사용하는 것처럼 통합을 가능하게 해주고 있다. 그리고 사례연구를 통하여 웹 컴포넌트의 모델분석과 설계를 하여 빈(Bean)을 생성하였으며, 결론으로 COM., CORBA Component(CCM), EJB기반 컴포넌트를 비교하였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권1호
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• pp.29-33
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• 1999

Superconducting tape is being developed for electrical equipment such as superconducting transformers and generators etc. AC loss reduction is primary concerned in the development of such high-efficiency equipment. AC losses in Bi-2223 silver-sheathed tapes, both single and multi-filamentary, were investigated by means of AC magnetization techniques when longitudinal fields are applied. The experiment resultswere compared with the hysteresis loss equation based on Bean model and the eddy current loss equation. The AC loss of the mono-filamentary tape was dominated by the hysteresis. On the contrary, the AC loss of the multi-filamentary tape was substantially dominated by the eddy current loss in the silver matrix.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.367-370
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• 1998

In this paper, based on the research of high temperature YBCO superconductor, using the Yb instead of Y, with the YbBCO superconductor powder which was combined by means of conventional solid reaction, textured directional crystal was prepared by MCP method and the character was analyzed. Mixing the starting elements and calcining at 890$^{\circ}C$, 900$^{\circ}C$, 910$^{\circ}C$, single phase YbBCO, Yb$_2$BaCuO$\sub$5/ and BaCuO$\sub$2/ were certified. And from the powder which was calcined at 900$^{\circ}C$ the, sample which became texture-growth by MCP method was well oriented. The result of DTA measurement, the fusing point of YbBCO superconductor and it\`s critical current was measured to be 979$^{\circ}C$, 87K respectively. The critical current density was obtained at the value of 700A/$\textrm{cm}^2$(77K. 0H) calculated by Bean's Model using the measured hysteresis curve of VSM.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.452-455
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• 2000

Superconducting power cable is one of the most promising energy application of high-T$_{c}$ superconductors (HTS). A prototype HTS cable have been constructed multi-layer cable using Bi-2223 tape and tested. The AC transport losses under self field were investigated at 77K on the 19 filamentary tape and multi-layer HTS cables. And we carried out numerical analysis using bean model. The result shows that the total transport current of HTS cable in L$N_2$ was 475[A], and transport current passed through almost the outer layer (2-layer). Also, AC transport losses in outer layer of HTS cable was proportion to I$^2$ and higher than losses of inner layer. In case of Ip=Ic, calculated numerical loss density was concentrated on the edge of tape and most of loss density in cable was distributed outer layer more than inner layer. As magnetic distribution was concentrated on outer layer.r.