• 제목/요약/키워드: Number of screens

검색결과 102건 처리시간 0.018초

대기 난류와 열적 블루밍을 겪는 고출력 레이저 빔의 대기 전파 시뮬레이션에 필요한 위상판 개수 분석 (Number of Phase Screens Required for Simulation of a High-energy Laser Beam's Propagation Experiencing Atmospheric Turbulence and Thermal Blooming)

  • 윤석영;문우현;김훈
    • 한국광학회지
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    • 제35권2호
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    • pp.49-60
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    • 2024
  • 본 연구에서는 킬로와트 급 고출력 레이저의 대기 전파 시뮬레이션에 필요한 위상판의 개수를 분석하였다. 킬로와트 급 레이저가 대기 중에 전파될 때, 주로 대기 난류와 열적 블루밍 효과에 영향을 받는다. 이에 따라 split step 방법을 사용하여 대기의 흡수 및 산란에 의한 손실, 그리고 난류와 열적 블루밍으로 인한 빔의 왜곡 현상을 구현할 때, 위상판의 개수는 시뮬레이션의 정확성 및 소요 시간을 결정짓는 중요한 요소이다. 본 연구에서는 광범위한 대기 난류 조건에서 많은 수의 위상판(예: 150개)을 사용하여 시뮬레이션을 진행하고, 레이저 출력 밀도 2.5×106 W/m2 (50 cm 직경 레이저 빔의 경우 500 kW 출력) 미만의 고출력 레이저 빔 전파 시뮬레이션에 필요한 위상판 개수에 대한 새로운 가이드 라인을 제시한다.

스털링기관 재생기내의 작동유체 유속 및 마찰저항 특성(II) - 작동유체 유동마찰저항 특성 - (Velocity and Flow Friction Characteristic of Working Fluid in Stirling Engine Regenerator (II) - Flow Friction Characteristic of Working Fluid in Stirling Engine Regenerator -)

  • 김태한;조창래
    • Journal of Biosystems Engineering
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    • 제33권1호
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    • pp.1-6
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    • 2008
  • The output of the Stirling engine is influenced by the regenerator effectiveness. The regenerator effectiveness is influenced by heat transfer and flow friction loss of the regenerator matrix. In this paper, in order to provide basic data for the design of regenerator matrix, characteristics of flow friction loss were investigated by a packed method of matrix in the oscillating flow as the same condition of operation in a Stirling engine. As matrices, two different wire screens were used. The results are summarized as follows; 1. With the wire screen of No. 50 as regenerator matrices, pressure drop of working fluid of the oscillating flow is shown as 3 times higher than that of one directional flow, not too much influenced by the number of packed meshes. 2. With the wire screen of No. 100 as regenerator matrices, pressure drop of working fluid of the oscillating flow is shown as 2.5 times on the average higher than that of one directional flow, not too much influenced by the number of packed meshes. 3. Under one directional flow which used regenerator matrices with both 200, 240, and 280 wire screens of No. 50 and 320, 370, and 420 wire screens of No. 100, the relationship between the friction factor and Reynold No. is shown as the following formula. $$f=\frac{0.00326639}{Re\iota}-1.29106{\times}10^{-4}$$ 4. Under oscillating flow which used regenerator matrices with both 200, 240, and 280 wire screens of No. 50 and 320, 370, and 420 wire screens of No. 100, the relationship between the friction factor and Reynold No. is shown as the following formula. $$f_r=\frac{0.000918567}{Re\iota}+1.86101{\times}10^{-5}$$ 5. The pressure drop is shown as high in proportion as the number of meshes has been higher, and the number of packed wire screens as matrices increases.

창호용 방충망의 성능기준 개선 방안 (Study on the improvement of the performance criteria for the Window Insect Screens)

  • 여인환;옥치열;안재홍;인기호;민병렬
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2009년도 춘계 학술논문 발표대회 산업계
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    • pp.61-64
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    • 2009
  • The number of apartment houses has accounted for more than 50% of all domestic residential types in Korea since 1980s. However, the apartment house has environmentally disadvantageous conditions such as highly residential-density and potential falls by children aged seven years and under through windows. In this study, we aim to suggest some ideas to improve domestic performance assessment methods and criteria of window Insect screens for protection on security and fall prevention by analyzing domestic standard with several overseas codes related to the screens for windows.

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디지털케이블TV에서 영화의 선행창구 성과, 장르, 홀드백 기간이 영화 VOD 구매에 미치는 영향 (The Effect of Number of Running Screens and Viewers in the Theaters, Genres, Holdback Period on the Number of Purchases of Movie VOD in the Digital Cable TV Subscribers)

  • 박선규;최성진
    • 방송공학회논문지
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    • 제20권6호
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    • pp.950-962
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    • 2015
  • 본 논문은 디지털케이블TV에서 2013년 3분기동안 편성한 169편의 유료영화 VOD를 대상으로, 영화의 선행창구성과인 누적관객수, 스크린 수, 그리고 장르와 홀드백 기간이 영화 VOD 구매에 미치는 영향을 분석하였다. 분석 결과, 편당 VOD 평균 구매건수는 2,540건으로 나타났고, 회귀분석 결과 선행창구성과인 스크린 수와 홀드백 기간이 영화 VOD 구매에 통계적으로 유의미한 영향을 미치는 것으로 분석되었고, 누적관객 수는 유의미한 영향을 주지 못했다. 장르별로 보면 SF/판타지 8,401건>드라마 4,011건>코미디 2,011건>액션 1,798건>애니메이션 1,138건>애정/멜로 1,119건>공포/스릴러 770건>에로 636건의 순으로 나타났다.

효율적인 화면요소 배치에 관한 연구 (A Study on the Efficient Layout Method of the Screen Components)

  • 김태우;박선이;여정모
    • 한국멀티미디어학회논문지
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    • 제23권2호
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    • pp.274-281
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    • 2020
  • The use of information systems improves a company's service quality and provides efficient information management. The establishment of an information system has become an essential element. In designing and developing a large number of screens when building an information system, As the number of screens increases, so does the cost and time. In addition, modifications can increase the cost of maintenance and exceed the cost of development. In order to solve these problems, there have been studies to design the screen simply and easily, but there is a shortage in reducing the maintenance cost. In this paper, we have studied the layout algorithm for managing the attributes of the screen components as data structures based on the designed screen and arranging the components on the screen. And we compared the proposed method and the methods that have been studied in the related studies. Screen component layout methods can automatically deploy screen components to consistently develop a large number of screens and reduce cost and manpower by reducing the time it takes to deploy screens.

증감지감도(增減紙感度)의 실태(實態)에 대한 조사(調査) (Research on the Actual Condition of Intensifying Screens)

  • 허준;김창균;강홍석;김성훈;윤한식;김정민
    • 대한방사선기술학회지:방사선기술과학
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    • 제5권1호
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    • pp.45-47
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    • 1982
  • Authors carried out the research on the actual condition of intensifying screens in a certain hospital and obtained the results as follows: 1. High speed intensifying screens were 63.9% and medium typed screen had 36.1%. 2. Half the number of using screens(51.5%) were not clear in a period of used time. 3. 47.4% of same typed screens showed a remarkable difference(two times) in sensitivity.

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Research on the Movie Reviews Regarded as Unsuccessful in Box Office Outcomes in Korea: Based on Big Data Posted on Naver Movie Portal

  • Jeon, Ho-Seong
    • 아태비즈니스연구
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    • 제12권3호
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    • pp.51-69
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    • 2021
  • Purpose - Based on literature studies of movie reviews and movie ratings, this study raised two research questions on the contents of online word of mouth and the number of movie screens as mediator variables. Research question 1 wanted to figure out which topics of word groups had a positive or negative impact on movie ratings. Research question 2 tried to identify the role of the number of movie screens between movie ratings and box office outcomes. Design/methodology/approach - Through R program, this study collected about 82,000 movie reviews and movie ratings posted on Naver's movie website to examine the role of online word of mouths and movie screen counts in 10 movies that were considered commercially unsuccessful with fewer than 2 million viewers despite securing about 1,000 movie screens. To confirm research question 1, topic modeling, a text mining technique, was conducted on movie reviews. In addition, this study linked the movie ratings posted on Naver with information of KOBIS by date, to identify the research question 2. Findings - Through topic modeling, 5 topics were identified. Topics found in this study were largely organized into two groups, the content of the movie (topic 1, 2, 3) and the evaluation of the movie (topics 4, 5). When analyzing the relationship between movie reviews and movie ratings with 5 mediators identified in topic modeling to probe research question 1, the topic word groups related to topic 2, 3 and 5 appeared having a negative effect on the netizen's movie ratings. In addition, by connecting two secondary data by date, analysis for research question 2 was implemented. The outcomes showed that the causal relationship between movie ratings and audience numbers was mediated by the number of movie screens. Research implications or Originality - The results suggested that the information presented in text format was harder to quantify than the information provided in scores, but if content information could be digitalized through text mining techniques, it could become variable and be analyzed to identify causality with other variables. The outcomes in research question 2 showed that movie ratings had a direct impact on the number of viewers, but also had indirect effects through changes in the number of movie screens. An interesting point is that the direct effect of movie ratings on the number of viewers is found in most American films released in Korea.

애니메이션 영화의 흥행결정 요인에 관한 연구 : 2003-2008년 개봉작품을 중심으로 (Predicting Box Office Performance for Animation Movies' Evidence from Movies Released in Korea, 2003-2008)

  • 정완규
    • 만화애니메이션 연구
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    • 통권16호
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    • pp.21-32
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    • 2009
  • 본 연구는 2003년부터 2008년까지 한국에서 개봉된 애니메이션 영화들을 분석대상으로 하여 해당 영화의 흥행성과에 영향을 미치는 요인들을 고찰하고자 한다. 종속변수는 전국 총관객수이다. 총관객수에 영향을 미치는 요인이 무엇인지 고찰하기 위해 독립변인은 배급사 파워, 개봉스크린 규모, 개봉시점, 속편형태, 수상실적, 영화의 국적 및 등급, 그리고 전문가 평점과 네티즌의 온라인평점으로 설정되었다. 회귀분석 결과에서 전국 관객수에 유의미한 영향력을 미치는 변수는 개봉스크린 규모, 할리우드직배사의 배급, 여름시즌 개봉, 그리고 네티즌 평점이다. 본 연구는 한국 영화시장에서 애니메이션 흥행성과에 대한 분석을 시도했다는 점에서 의의를 찾을 수 있을 것이다.

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와이어 망을 이용한 충돌 수분류의 열전달 증진 (Heat Transfer Augmenttaion by use of Wire Mesh-Screens in Impinging Water Jet)

  • 윤상호;이종수;최국광
    • 태양에너지
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    • 제19권3호
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    • pp.43-51
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    • 1999
  • Axisymmetric circular water jet impinges against rectangular heated surface with uniform hear flux and wire-mesh screens are set up in the nozzle-to-heater space to augment heat transfer. In the free jet region to be used them, pressure drop and intensive turbulence flow was brought up. When water jet system is not used wire-mesh screens, maximum heat transfer appears in the stagnation point and the secondary maximum appears X/D=4 but it disappears when they are is used. In the low velocity(Vo<6.0m/s), coarse mesh-screen enhanced heat transfer but fine mesh-screens inpeded heat transfer. In the high velocity(Vo>6m/s), all of them enhanced heat transfer. Average Nusselt number of experimental system to be used wire-mesh screens was promoted $4{\sim}6$times than that of simple water jet system. The stagnation heat transfer of experimental system to be used wire-mesh screens was augmented 6times that of simple water jet system.

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VDT작업공간의 적정휘도분포 추출에 관한 연구 (A Study on the Extraction of the Preferable Luminance Distribution in VDT Workspaces)

  • 정진현;이진숙
    • 한국조명전기설비학회지:조명전기설비
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    • 제9권3호
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    • pp.59-66
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    • 1995
  • In this study through a series of the experiments, 1) the preferable luminance values of the CRT screens, 2) the preferable luminance ratios between the CRT screens and its surrounding surfaces are determined. The results are evaluated by the level of satisfaction, and re-examined by the work performance (number of types, rate of errors) and the level of eye fatique (number of blinks, near point distance)

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