• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.52-61
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• 2020

The natural change of winter night temperature from 00:00 to 04:30 O'clock with the different height of thermal screen in a venlo type glasshouse (W59×L68×H5.9 m) was studied using computational fluid dynamics (CFD). At the early stage of CFD analysis, the room temperature decrease of glasshouse with the 5.9 m height of thermal screen were faster than it with the 4.1m height of thermal screen, but at 2 hr after analysis it was slower than in it with the 4,1m, the temperature difference was 0.6℃ after 4 hr. If we consider that turn on the heater when the temperature were decrease below 13℃ at 1hr after CFD analysis, it is good for energy saving in the glasshouse with the 4.1 m height of thermal screen rather than in it with the 5.9 m height, because of the temperature decrease were slow during 2 hrs after analysis. The airflow at the height of 2 m which were grown tomato were fast and wide in the glasshouse with the 5.9 m height thermal screen rather than in it with the 4.1 m, the speed difference was 0.034m·s^-1 at 1hr after CFD analysis. The effect of temperature decrease in summer season were compared with the different height of shading screen from 12:00 to 14:30 O'clock. The height of shading screen were 5.7, 3.9 m, the gap of it were 30%. The air-inflow quantity by the fan with duct at lower part of venlo glasshouse was 0.67 ㎥·s^-1 until 1hr and to increase 3 times of it from 1hr after analysis. The roof window were open 100%. Until 1hr of CFD analysis, the temperature in the 30% open of shading screen was 0.9℃ higher than in the none shading screen. From 13:00 O'clock when the air-inlet quantity to increase 3 times, the temperature in case 30% gap of shading screen were decreased compare with the none shading screen, the temperature difference was 0.5℃ at 14:30 O'clock. The temperature on the floor surface in case 30% gap of shading screen were lower with it's height increase, the temperature difference was 8℃ compare with none shading screen. The relative humidity difference were insignificant by the height and gap of shading screen.

• 프린팅코리아
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• s.23
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• pp.98-110
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• 2004

인쇄의 품질을 높이는 방법은 여러 가지가 있다. 그 중에서 어떤 스크리닝 기술을 선택하느냐에 따라서도 인쇄의 품질이 달라질 수 있다. 그래서 프리프레스 솔루션 공급업체들은 고품위 인쇄를 위해 300선 이상의 고정세 인쇄, 미세 도트 밀도에 의해 화상의 농담을 표현하는 FM 스크린 그리고 AM과 FM 스크린의 장점을 이용해 사용하고 있는 혼합 망점 등을 활용할 수 있는 기술들을 소개하고 있다. 이것은 인쇄업계에서 일반적으로 사용하고 있는 175선의 AM 스크린이 모아레(얼룩무늬)가 생긴다는 단점이 있었기 때문에 이를 보완하기 위해 나온 기술들이다.

• Journal of Power System Engineering
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• v.15 no.3
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• pp.31-37
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• 2011

직조 금속 스크린 리브(rib) 이 바닥에 설치된 사각 덕트에서 열전달과 유체유동의 압력강하를 측정하기 위해 실험적 연구를 수행하였다. 시험부의 치수는 200 mm(W) ${\times}$ 40 mm(H) ${\times}$ 712 mm(L)이고 수력직경은 66.6 mm이다. 입구영역에는 1.72m 길이의 가열되지 않은 동일한 치수의 채널을 설치하였다. 메쉬가 다른 4가지의 직조금속 스크린 리브에 대해 측정하였다. 그리고 비교를 위해 일체형 리브에 대해서도 측정하였다. 국부 열전달 계수의 측정에는 스테인레스 강제 포일(foil) 히터와 T형 열전대률 이용하였다. 레이놀즈 수는 23,000에서 58,000의 범위이다. 덕트의 수력직경($D_h$)에 대한 직조 금속 리브의 높이(e)의 비($e/D_h$)는 0.075 이고 리브 간격(p)과 높이의 비(p/e)는 10이다. 실험 결과 메쉬가 없는 일체형 리입에서 가장 누셀트 수와 마찰계수가 컷다.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.1502-1505
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• 2013

프레젠테이션을 위한 기존 방비들은 기능이 제한적이거나 또는 고비용이라는 문제점을 가지고 있다. 본 논문에서는 깊이 카메라를 이용한 손의 터치와 터치위치와 프레젠테이션 내용을 조합하여 프레젠테이션의 자유도를 높이는 방법을 제안한다. 제안 방법은 깊이 카메라로부터 스크린 영역의 깊이 값을 배경으로 설정하고, 배경과 차이나는 객체가 들어오면, 객체의 깊이 값과 배경의 깊이 값을 비교하면서 포인터를 추출한다. 모의실험 결과로부터 스크린의 상하좌우 중에 한곳에 카메라를 설치하고 프레젠테이션 페이지마다 서로 다른 위치에서 터치가 인식되고, 다양한 프레젠테이션 이벤트가 실행됨을 확인하였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.155-159
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• 2014

In this paper, we describe algorithm and digital circuit implementation of touch screen controller that has the faster response time. We enhance the response time by adaptive search method instead of linear search method of step level in the pulse width decision. The faster response time might bring effects of feeling better in the touch keyboard. The performance of the proposed algorithm and function is verified by using logic simulation and FPGA test board. It is expected to use in the mobile touch screen.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.2
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• pp.196-203
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• 2011

Experiments to determine heat transfer coefficients and friction factors are conducted on a stationary transverse parallel wire-screen rib roughened rectangular channel. The test section consists of 198 mm (W) x 40 mm (H) x 712 mm (L). The channel has the aspect ratio of 4.95 and hydraulic diameter of $D_h$=6.66 cm. Four wire screen ribs and a solid rib are used. 0.1 mm-thick-stainless steel foil heaters and thermocouples (T type) are used to measure the heat transfer coefficients. Reynolds numbers studied range from 20,000 to 60,000. The wire-screen rib height (e) to hydraulic diameter ($D_h$) ratio ($e/D_h$) is 0.075; spacing (p) to height ratio (p/e) is 10. Results indicate that the solid rib produces the greatest Nusselt number and friction factor.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.4
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• pp.663-670
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• 2019

The modified Canny edge detection algorithm that can detect the boundary between screen door and platform in the subway is proposed in this paper. Generally, in the subway, the boundary line between the platform and the screen door is darker than the surrounding area. Therefore, an edge image is using the modified bottom-hat transform by considering its characteristics. Double thresholded images with strong edge and weak edge through double thresholding are obtained. An algorithm that detects the boundary invasion between the platform and the screen door is proposed by calculating the length by applying the Hough transform to the double thresholded image and comparing the boundary line length between when there is an object such as a person and when there is no object. In this paper, the results of the proposed modified Canny edge detection algorithm using two different input images according to camera height position are shown by computer simulation.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.41.2-41.2
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• 2005

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.43-46
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• 2013

Active use of images in the same place as the religion according to the height of the screen is determined by the height of the main speakers. This causes the 'sound image mismatch' and 'bass boost' sound like a failure occurs. Front seats are good seats in visual acoustics is a bad place. To minimize these obstacles acoustical speakers to actively apply the front fill needed. Higher sound pressure difference between the main speaker and the distance must be determined in accordance with the appropriate capacity. Actively using the front speakers to the sound image field by implementing the agreement to increase the concentration of sound. The relatively high inflow enhance alto lacking the front seat can be implemented evenly in the frequency response. Column in front of the main seat of the main speakers to supplement the deficiencies can be implemented more comfortable acoustic environment. Front fill speaker needs to be actively introduced, thereby presenting a detailed estimate, is needed.

• Journal of Broadcast Engineering
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• v.18 no.3
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• pp.409-415
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• 2013

Recently, various equipments have been developed for convenience of presentations. Presentation equipments added the keyboard and mouse functions to laser pointer and devices have become main method. However these devices have demerits of limited action and a few events. In this paper, we propose a method which increases the degrees of freedom of presentation as the control of the hand by using a depth camera. The proposed method recognizes the horizontal and vertical positions of hand pointer and the distance between hand and camera from both depth and RGB cameras, then performs a presentation event as the location and pattern that the hand touches a screen. The simulation results show that a camera is fixed on left side of the screen, and nine presentation events is correctly performed.