• Title/Summary/Keyword: Type & screen

Search Result 611, Processing Time 0.031 seconds

Large viewing angle walk through type display using smoke screen

  • Sato, Koki;Takano, Kunihiko;Ohki, Makoto
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2009.01a
    • /
    • pp.790-793
    • /
    • 2009
  • In the case of projection type display, it needs to use the screen in order to project the image clearly and wide viewing angle. We have been developing the step in type display system using the smoke screen. However, the image with smoke screen was flickered by gravity and air flow. Then we considered to reduce the flicker of the image and we found that flicker can be reduced and viewing angle becomes more large. This time we report the large viewing angle step in type display system using screen made up with very small particle size smoke and flow controlled nozzle. Hence, at first we considered the most suitable particle for the screen and then the shape of screen and then we constructed the array of flow controlled smoke screen. By the results of experiment we could get considerably high contrast flicker-less image and get the viewing angle more than $60^{\circ}$ by this flow controlled nozzle attached new type smoke screen and make clear the efficiency of this method.

  • PDF

Reduction of Exposure dose in Cheat Roentgenography (흉부X선검사(胸部X線檢査)에 있어서 피폭선량(被曝線量)의 경감(輕減)에 대한 검토(檢討))

  • Huh, Joon;Kim, Chang-Kyun;Kang, Hong-Seok
    • Journal of radiological science and technology
    • /
    • v.2 no.1
    • /
    • pp.15-22
    • /
    • 1979
  • Author made a experiment on the exposure dose with various intensifying screens in taking chest roentgenogram and obtained the results as follows; 1. Special speed type was the most sensitive intensifying screen, the r(gamma) value of this screen was distributed from 2.6 to 2.9. 2. The resolution activity of intensifying screen was inversely proportional to its sensitivity. If, the sensitivity and detail of the fine detail speed type intensifying screen at 100 KV were 100, those of the special speed type were 549 and 54.44 respectively. 3. If the exposure dose of the fine detail type intensifying screen was 1.0 at 60 KV, that of the special speed type intensifying screen was 0.1 at 80KV, and the skin dose of patient was as follows; it was 64.8 mRad at 60KV in mid speed type, 8.1 mRad at 80KV in super high speed type, and 7.2 mRad at 80KV in special speed type intensifying screen respectively.

  • PDF

Reflection-type Three-dimensional Screen using Retroreflector

  • Song, Byoungsub;Choi, Sungwon;Sung, Hyunsik;Min, Sung-Wook
    • Journal of the Optical Society of Korea
    • /
    • v.18 no.3
    • /
    • pp.225-229
    • /
    • 2014
  • A reflection-type three-dimensional (3D) screen using retroreflector is proposed to improve the visibility of a projected 3D image while keeping its perspective. For the projection-type 2D display, the diffuser is used to represent the 2D scene, overcoming the limitation of the aperture of the projection lens set. If the diffuser is adopted for the projected 3D image, only 2D images sectioned and blurred should be displayed on the screen. The proposed screen can make the 3D image with the aperture limitation visible to be applied to the 3D image projection systems. The feasibility of the proposed screen is verified by experiments.

Measurements and Analysis of Electromagnetic Shielding Effectiveness of PDP TV Screen Filters (PDP TV Screen Filter의 Shielding Effectiveness 측정 및 분석)

  • Park, Gyu-Bok;Kim, Yoon-Jung;Kim, Young-Soo
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
    • /
    • 2003.11a
    • /
    • pp.47-53
    • /
    • 2003
  • Screen filter of PDP TV plays an important role in satisfying the EMI/EMC specifications. Two types of filters, the mesh type and the sputter type, are used in PDP TVs, and this paper presents measurement results of the shielding effectiveness (SE) in the frequency range from 50MHz to 1GHz. Two methods were used for the measurement, one using network analyzer (NA) in an open area test site(OATS), and the other using the screen room. The overall conclusion is that the shielding effectiveness of the screen filter is related to the surface resistance of the screen filter. The mesh type screen filters are superior to the sputter types in the shielding effectiveness, which is varying with the frequency.

  • PDF

Use of Multifractor in the Paper Mills for Recycled Fibers (II) - Hole screen cases - (고지섬유의 효율적 이용을 위한 Multifractor의 활용분석 (II) - Hole screen을 사용하는 경우 -)

  • Seo, Yung-Bum;Yoon, Hye-Jung;Lee, Young-Joon;Joo, Yong-Hoon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.42 no.1
    • /
    • pp.20-25
    • /
    • 2010
  • Fractionation effects of the slot-type and the hole-type screens of mutifractors were studied using a pilot multifractor. We used a slot screen of 0.15 mm, and two hole screens of 1.0 and 2.0 mm, respectively, in the study. We found hole-type screens were more effective for fractionation of fiber furnishes according to their fiber lengths. Slot-type screen was more effective to remove the shives from the accepted fiber furnishes. There existed a high regression coefficient between the fiber length differences and the freeness differences of the accepted and the rejected fiber furnishes.

Analysis on the Train-wind Pressure applied to Screen Door in Island-type Platform of Subway (지하철의 섬식 정거장에 설치된 스크린도어에 가해지는 열차풍압 해석)

  • Kim, Jung-Yup
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.138-141
    • /
    • 2008
  • The screen doors installed in the station of subway are subject to the train-wind pressure caused by the operation of trains. The train-wind pressure has to be correctly estimated for the design of safe structure of screen doors. As three-dimensional numerical flow analysis technology has been significantly developed, the analysis on the train-wind pressure with diverse variables such as train specifications, train speed, tunnel and station configurations, and blockage ratio can be effectively carried out with three-dimensional numerical method. In this study, computational analysis of train-induced wind in a subway tunnel employing the screen doors are carried out by using the three-dimensional numerical method with the model of the moving boundary for the run of trains. While the numerical analysis of train-wind pressure was applied on the one island-type station in the Seoul Subway Line 2, maximum pressure of 494 Pa was estimated on the screen door when two trains pass each other at the speed of 80km/h in the platform.

  • PDF

A study on the $ALU^+$ crystalline solar cell characteristics affected by counts of rear side screen printings ($ALU^+$를 이용한 결정질 태양전지 후면 전극 Screen Printing 횟수에 따른 특성)

  • Choi, Jaewoo;Kim, Hyunyup;Yi, Junsin
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2011.05a
    • /
    • pp.123.1-123.1
    • /
    • 2011
  • 기존의 p-type 태양전지 공정과 유사한 공정으로 제작되는 n-type $ALU^+$태양전지는 후면에 Al을 screen printing하여 emitter층을 형성한 구조이다. screen printing은 공정의 단순화와 제조 단가의 저비용으로 인해, metalization 공정에서 많이 쓰이고 있다. 본 연구에서는 양산 가능한 n-type $ALU^+$태양전지 제작을 위해, 후면 Al emitter 층을 single, dobule, triple로 변경하며 Al의 양을 가변하였고, 그에 따른 특성의 변화를 연구하였다. screen printing 횟수가 변경된 후면 Al emitter 층의 특성은 DIV와 LIV 측정을 통해 분석하였다. 실험 결과 Al을 single printing 하였을 때보다, double, triple printing을 통하여 Al의 양을 증가하였을 때, DIV 데이터에서 직렬저항(Rs)가 $24.44{\Omega}/cm^2$에서 $0.31{\Omega}/cm^2$으로 감소하였고, 단락전류(Jsc)는 1.26mA/$cm^2$에서 37.7mA/$cm^2$으로 약 300% 증가한 것을 확인할 수 있었다. 프린팅 횟수에 따른 LIV 데이터의 Fill Factor를 분석하게 되면, double printing이 64.35%로 54.75%의 triple printing보다 약 1.17배 더 향상된 것으로 확인하였다. 이러한 결과를 바탕으로 후면 Al emitter 형성시에 Al의 양이 적절하지 못한 이유로, Al emitter가 제대로 형성되지 못하거나 과하게 형성되면, 태양전지 내부에 누설 저항의 변화와 누설 전류의 증가로 인해, 단락전류(Jsc)와 Fill Factor 감소의 주요 원인이 된다는 것을 확인할 수 있었다.

  • PDF

Comparison of the 3D Tab Page Type for the Small Screen Device (작은 스크린 환경에서 3D 페이지 전환 방식의 비교)

  • Lee, Jeonghyun;Park, Jaekyu;Choe, Jaeho;Park, Sungjoon;Jung, Eui S.
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.41 no.2
    • /
    • pp.137-143
    • /
    • 2015
  • This thesis focuses on the 3D interface tab page type and mode of screen that affect the usability of the small screen devices such as smartphone. The experiments examined eight 3D UI designs, combinations of two modes (Portrait, Landscape) of screen, and four types (Vertical data mountain, Horizontal data mountain, Vertical carousel, Horizontal carousel). Twenty-six participants participated in the experiment. The completion time, preference and fun score were measured. The results showed that the vertical data mountain type provide the best performance in terms of the all conditions. The results of this study suggest a practical approach for the 3D UI tab page design for the small screen devices.

Fluid Flow Resistance in a Channel with Wire-screen Baffles (와이어 스크린 배플이 설치된 채널에서의 유체유동 저항)

  • Oh, S.K.;Ary, B.K.;Ahn, S.W.
    • Journal of Power System Engineering
    • /
    • v.13 no.2
    • /
    • pp.36-41
    • /
    • 2009
  • An experimental investigation was conducted to examine the fluid flow resistance in the rectangular channel with two inclined wire screen baffles. Two different types of wire screens; dutch weave and plain weave, were used as baffle devices in this experiment. Three kinds of baffles with different mesh specifications were made up of dutch type and four different kinds of baffles were made up of plain weave type. The stainless steel wire screen baffles were mounted on the bottom wall with varied angle inclination. Reynolds numbers were varied from 23,000 to 57,000. Results show that the mesh number of baffles plays an important role on friction factor behaviour. It is found that the baffle with the most number of meshes (type SA) has the highest fluid flow resistance.

  • PDF