• 제목/요약/키워드: value gap

검색결과 1,039건 처리시간 0.024초

고온초전도동기모터의 부하변동에 따른 계자권선의 교류손실 해석에 관한 연구 (A Study on the Analysis for Ac-losses of the Field Winding considering Load Changes of High-Tc Superconducting Synchronous Motor)

  • 윤용수;송명곤;장원갑;장인배;홍계원;이상진;고태국
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제48권4호
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    • pp.167-173
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    • 1999
  • The use of high-Tc superconducting synchronous motor in power machinery has many advantages such as reduced power dissipation, size and weight. This paper presents the ac loss simulation in the rotor having an high-Tc superconducting field winding using Ag sheathed Bi-2223. The analysis was conducted with an equivalent model of the high-Tc superconducting motor with flux damper under transition condition during which the load varies from 0 watt to 250watts and from 250watts to 500watts. The simulation results show that the transient state lasts for about 3 seconds, and the ac losses decreased exponentially from the initial value above 20mW.

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전자빔 증착기로 제조된 $CuInS_2$ 박막의 전기적,구조적 특성 (Electrical and Structural Properties of $CuInS_2$ thin films fabricated by EBE (Electrical Beam Evaporator) Method)

  • 양현훈;김영준;박중윤;정운조;박계춘
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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    • pp.49-51
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    • 2006
  • Ternary chalcopyrite $CuInS_2$ thin film material is very promising for photovoltaic. Power generation because of its excellent optical and semiconductor properties, $CuInS_2$ thin films were performed from S/In/Cu/SLG stacked elemental layer (SEL) method with post annealing treatment. $CuInS_2$ thin films were appeared from 0.84 to 1.27 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated. Analysis of the optical energy band gap of $CuInS_2$ value of l.5eV interior and exterior.

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Si 태양전지(太陽電池)의 표면재결합(表面再結合) 전류(電流)가 포화전류(飽和電流)에 미치는 영향(影響) (The Effect of Surface Recombination Current on the Saturation Current in Si Solar Cell)

  • 신기식;이기선;최병호
    • 태양에너지
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    • 제8권2호
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    • pp.12-18
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    • 1988
  • The effect of surface recombination current density on the saturation current density in Si solar cell has been studied. Theoretical model for surface recombination current was set up from emitter transparent model of M.A. Shibib, and saturation current of Si solar cell made by ion implantation method was also measured by digital electrometer. The theoretical surface recombination current density which is the same as saturation surface recombination current density in Shibib model was $10^{-11}[A/cm^2]$ and the measured value was ranged from $8{\times}10^{-10}$ to $2{\times}10^{-9}[A/cm^2]$. Comparing with the ideal p-n junction of Shockley, transparent emitter model shows improved result by $10^2$ order of saturation current density. But there still exists $10^2$ order of difference of saturation current density between theoretical and actual values, which are assumed to be caused by 1) leakage current through solar cell edge, 2) recombination of carriers in the depletion layer, 3) the series resistance effect and 4) the tunneling of carriers between states in the band gap.

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운동 부하 조절이 가능한 원형 맴돌이전류 부하 제동장치의 성능 분석 (Analysis of Performance for Exercise Load Adjustable Circular Eddy Current Load Brake system)

  • 나기수;이응혁
    • 재활복지공학회논문지
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    • 제9권3호
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    • pp.231-236
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    • 2015
  • 본 연구에서는 재활운동기기에 적합한 운동부하 조절이 가능한 영구자석형 비 접촉식 원형 브라켓 맴돌이 전류 부하 제동장치를 제안하고 성능을 실험적으로 평가하였다. 제안한 원형 부하 제동장치의 토크 값은 고정 부하를 갖는 "ㄷ"형 부하 제동장치에 비해 49%의 제동력으로 평가되었지만 도전율 변화와 공극의 간격 변화로 다양한 부하 조절이 가능함을 확인하였다. 본 연구에서 제안된 부하 제동장치는 사용자의 상태에 따라 부하 조절이 가능하며 운동기기의 소형화 및 원가 절감 등의 장점을 갖는 운동기기 적용이 가능할 것으로 기대된다.

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A temporary evacuation area like open space analysis for disaster prevention town considering probability of street blockade-

  • Hidaka, Yutaro;Mishima, Nobuo;Wakuya, Hiroshi;Hayashida, Yukuo;Okazaki, Yasuhisa;Kitagawa, Keiko;Park, Sun-gyu;Oh, Yong-sun
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2016년도 춘계 종합학술대회 논문집
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    • pp.239-240
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    • 2016
  • Traditional town with wooden houses like Japanese historic local town is vulnerable to disaster. Wooden houses crowed in this study area, there is no gap between buildings and buildings. When disaster occurs, they can not use evacuation routes based on the value of probability of rubble flow. Disaster prevention design of traditional town using spatial information for residents is a modern idea in the field of disaster prevention study. Therefore, it is basically important and effective to create information, especially on the current situation such as dangerousness of the area. Here, we report on a disaster prevention design regarding probability of street blockade and probability of rubble flow at a large earthquake directly under our study area. In this study, we explain about necessity of temporary evacuation areas like open space. As a result, we found some ideas to secure evacuation routes from traditional houses to designated refuge places using temporary evacuation areas.

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Local Similarity based Document Layout Analysis using Improved ARLSA

  • Kim, Gwangbok;Kim, SooHyung;Na, InSeop
    • International Journal of Contents
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    • 제11권2호
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    • pp.15-19
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    • 2015
  • In this paper, we propose an efficient document layout analysis algorithm that includes table detection. Typical methods of document layout analysis use the height and gap between words or columns. To correspond to the various styles and sizes of documents, we propose an algorithm that uses the mean value of the distance transform representing thickness and compare with components in the local area. With this algorithm, we combine a table detection algorithm using the same feature as that of the text classifier. Table candidates, separators, and big components are isolated from the image using Connected Component Analysis (CCA) and distance transform. The key idea of text classification is that the characteristics of the text parallel components that have a similar thickness and height. In order to estimate local similarity, we detect a text region using an adaptive searching window size. An improved adaptive run-length smoothing algorithm (ARLSA) was proposed to create the proper boundary of a text zone and non-text zone. Results from experiments on the ICDAR2009 page segmentation competition test set and our dataset demonstrate the superiority of our dataset through f-measure comparison with other algorithms.

Preliminary evaluation of some aspects of the ecology (growth pattern, condition factor and reproductive biology) of African pike, Hepsetus odoe (Bloch 1794), in Lake Eleiyele, Ibadan, Nigeria

  • Ogunola, Oluniyi Solomon;Onada, Olawale Ahmed;Falaye, Augustine Eyiwunmi
    • Fisheries and Aquatic Sciences
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    • 제21권3호
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    • pp.12.1-12.15
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    • 2018
  • A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year.

RF 마그네트론 스퍼터링 법으로 제작한 ITZO 박막의 구조 및 광학적 특성 (Structural and Optical Properties of ITZO Deposited by RF Magnetron Sputtering)

  • 김동렬;배지환;황동현;손영국
    • 한국표면공학회지
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    • 제48권6호
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    • pp.292-296
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    • 2015
  • Indium tin zinc oxide (ITZO) thin films were deposited on glass and quartz substrates by RF magnetron sputtering. The substrate temperature varied from $100^{\circ}C$ to $400^{\circ}C$. The structural and optical properties of thin films were investigated by X-ray diffraction (XRD), Field Emission Scanning electron microscopy (FESEM) and UV-Visible transmission spectra. It has been found from X-ray diffraction patterns that increasing the substrate temperature, the amorphous structure changes into polycrystalline structure. The FESEM results showed that all ITZO thin films have a smooth surface. The average optical transmittance (400 - 800 nm) was 82% and 80% at all films deposited at $200^{\circ}C$. The band gap energy ranges 3.41 to 3.57eV and 2.81 to 3.44eV with a maximum value at $200^{\circ}C$ all substrates temperature.

자막정보를 이용한 새로운 스마트TV 사업 모형설계 (The Design of Smart TV Business Model Using subtitle Information)

  • 나인섭;김수형;나형율
    • 스마트미디어저널
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    • 제1권4호
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    • pp.35-43
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    • 2012
  • 이 논문에서는 스마트TV 현황을 살펴보고, 바뀐 스마트 생태계에서 자막정보를 이용한 새로운 스마트 TV 사업 모형을 제시하였다. 현재 우리사회는 스마트 TV에 대한 긍정적인 견해와 유보적 견해가 있음에도 불구하고 스마트 TV로의 큰 변화는 우리 시대에 거부 할 수 없는 큰 물결이며, 점진적으로 스마트 TV를 중심으로 모든 사회가 바뀌어나갈 수밖에 없다. 따라서 이 논문에서는 양방향, 능동적, 소비자 중심의 스마트TV환경에서 자막정보를 이용한 새로운 스마트 TV 사업 모형을 설계하였다. 끝으로, 제안된 자막정보를 이용한 스마트 TV 사업모형은 한류 시대에 국가 간 정보의 격차를 줄이고 한류를 확산하는 데 일익 할 것이 기대된다.

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인간-제품 인터페이스의 사용성 평가 (An Evaluation of Human-Product Interface Usability)

  • 최재하;박영택
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1997년도 추계학술대회논문집
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    • pp.249-259
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    • 1997
  • As the gap between competing products narrows in terms of performance and quality, the product usability is rapidly becoming a new dimension of product design as the key to offering distinctive value to the customer. Because the user interface is important, not only for the user but also for the efficiency of te whole organiation, system designers require increasingly precise evaluation methods to determine how effective and usable human-product interface is. In this study a new methodology named usability analysis diagram(UAD), for evaluating usability of human-product interface systematically, was developed. UAD is a top-down flow diaagram of a human-product interaction, in ehichfour basic elements - perception, understanding, intellectual decision and action - were classified and then represented by a particular symbol for each. The usability of the product is assessed by the frequency of each symbol in a diagram which represents a sequence of cognitive and physical activities of users during the use of the product, and by the level of difficulty that is classif- ied in three levels in terms of easiness of perception, understanding and action. In order to test validity of the proposed UAD in a real situation, a case study was performed on two different cameras, automatic and manual, and their usability was successfully evaluated and compared.

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