• Journal of the Optical Society of Korea
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• v.4 no.1
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• pp.58-61
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• 2000

Viewing zone shape and size perform a key role in creating viewing comfort for the viewer. The horizontal and vertical sizes of viewing zones, formed by a full color transmission type holographic screen with a stereoscopic image projection are investigated. The screens have been recorded as holograms of a narrow stripe shaped object with different width; to extend the vertical size of the viewing zone the holograms were exposed two times with the hologram shifting between exposures. The viewing zone parameters were measured as a function of the stripe width of the object and of the exit pupil size of projection optics for several holographic screens having the size of the 30 $\times$ 40 $\textrm{cm}^2$.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.6
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• pp.145-154
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• 2013

Recently, damage occurrence by wind erosion has been increasing in society. In times past, such problems only took place in desert area ; however, in recent years, the wind erosion problem is spreading out to agricultural land. Wind erosion in agricultural land can cause loss of loam soils, the disturbance of the photosynthesis of the crop fields and serious economic losses. To overcome the mentioned problems, installation of windbreak fence can be recommended which function as disturbing strong wind and wind erosion. However, there is still no proper guideline to install the windbreak fence and the installation used to rely on the intuition of the workers due to the lack of related studies. Therefore, this study measured the aerodynamic resistance of screens of the windbreak fence using the apparatus for testing screens. The apparatus for testing screens was designed to measure pressure loss around the screen. Measured pressure loss by wall friction compensated for pressure loss to calculate the aerodynamic resistance of screens. The result of pressure loss by regression analysis derived the aerodynamic coefficient of Darcy-Forchheimer equation and power law equation. The aerodynamic resistance was constant regardless of the overlapped shape when the screen was overlapped into several layers. Increasing the number of layers of the screen, internal resistance increased significantly more, and pressure loss caused by the screen also increased linearly when the wind speed was certain conditions, but permeability had no tendency. In the future, the results of this study will be applied to the computational fluid dynamics simulation. The simulation models will be also validated in advance by wind tunnel experiments. It will provide standard of a design for constructing windbreak fence.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3C
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• pp.264-270
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• 2010

Non-planar screens such as cylinder and sphere shaped screens are widely used for high-resolution immersive visualization environments. An existing method employs quadric matrix that maps an image onto a curved screen. However if the shape of the screen changes or moves, the quadric matrix will not be valid. In this paper, we assume that the screen is a quadric shape and the screen movement or change are relatively small. Then we propose to use a piecewise planar approximations for the screen to compensate for the geometric distortion on a non-planar screen. We demonstrate the effectiveness and efficiency of the proposed method through experiments.

• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.100-121
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• 2023

This paper examines the interior settings of a chamber and of a temporary place of enshrinement at Yeonghuijeon (永禧殿, Hall of Eternal Happiness), the representative official portrait hall in which portraits of early and late Joseon kings were enshrined. Also, it discusses the features of the Five Peak screens used therein. The physical environment of a chamber at Yeonghuijeon mainly consisted of a four-panel folding screen with a painting of Five Peaks and a large wooden platform, which was adorned with dragon and lion patterns and attached to lotus-leaf column balustrades. The Five Peak screen was installed on a large platform in the shape of ⊓, spreading across the second and third panels on the back and folding out on the first and fourth panels on the right and left sides. When a portrait was enshrined in a temporary place, a simpler and smaller platform with railings was used. A four-panel folding screen of the Five Peak painting was installed in the same way as in a chamber, but was unfolded around a smaller platform behind it. A royal portrait was displayed in each chamber, whereas a case in which a portrait was rolled up was put on the smaller platform in a temporary place. The Five Peak screens for a chamber and a temporary place were all large four-panel folding screens with two wide panels in the middle and two narrow panels on each side, and only strips of silk were mounted on the four edges of the screens without additional wide lower-side mountings. While screens for the chamber used patterned silk for mounting and white paper for backing on screen frames, screens for the temporary place used plain silk and recycled failed test papers for mounting and backing, respectively. By examining records in the literature on the Five Peak screens for Yeonghuijeon, this paper highlights two Five Peak screens, both of which lost their provenance from the hall. The structures of the two screens reflected the way they were to be installed at the hall. Furthermore, this paper assumes that a Five Peak screen, which had been unfolded on the throne in the main hall of Changdeokgung Palace after the 1960s, was produced in 1858 for the purpose of temporarily enshrining King Sunjo's portrait due to the fact that failed test papers of the 1840s were laid taut over the frame.

• Korean Journal of Heritage: History & Science
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• v.55 no.1
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• pp.243-263
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• 2022

The royal court of Joseon had a tradition of mounting the Irworobongdo, a painting of the sun, the moon and the five sacred peaks, symbols of the king's immortal presence and authority, on a folding screen and placing it in special spaces within the palace that were reserved for the king. While the Irworobongdo is generally accepted as the important ceremonial object of the royal palaces of Joseon, there have been few studies on the various folding screens used in the royal palaces, largely because the official records about such screens do not match the remaining original relics. In this study, the main discussion is focused on the diversity of the shapes and mounting materials of the Irworobongdoused for various ceremonies held in the royal palaces of Joseon based on the Uigwe, the official records of the royal protocols of the Joseon dynasty. The discussion also extends to the theme rarely studied so far, namely the original form of the Irworobongdo and its evolution in the following period. The ceremonial "five peak" folding screens (Obongbyeong) used at a number of important palace buildings, including the crown hall (Jeongjeon), royal funerary hall (Binjeon), spirit hall (Honjeon) and portrait shrine (Jinjeon), differed in shape and size from the folding screens used in royal celebratory events such as banquets, although the paintings themselves and the style of mounting them were essentially the same. The paintings were mounted on screens bordered with green silk and ornamented with floral gilt designs. The folding screens used in royal ceremonies were produced according to strict guidelines that required the ceremonies and mounting materials to be graded on the basis of the status of each screen. It was not until the 1960s that these ceremonial folding screens of the Joseon dynasty, which had been neglected during the period of Japanese colonial rule of Korea, began to undergo conservation treatment provided as part of a heritage preservation program. Unfortunately, many of the screens repaired in this period lost some of their original features - largely due to the use of non-traditional mounting techniques. Considering, however, that significant achievements have since been made in the heritage preservation field based on the use of historical evidence, it is now necessary to systematically use the repair history of the information about the remaining royal ceremonial folding screens to ensure that they are preserved and managed more effectively in the future.

• Journal of radiological science and technology
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• v.16 no.1
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• pp.41-55
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• 1993

Recently, various screen film system have been introduced in diagnostic radiology. There are two kinds of screen film system : blue emitting $CaWO_4$ screen has been largely used in these days. However, it tends to be changed to use green emitting $Gd_2O_2S$ : Tb screen. In this study, photographic characteristics of $CaWO_4$ and $Gd_2O_2S$ : Tb screen were investigated with luminescence, spectroscopy. The morphology of $CaWO_4$ and $Gd_2O_2S$ : Tb were also observed by using scanning electron microscope. The result obtained were as follows : 1. There was small difference in the thickness of phosphor layers for the front and back screen of blue emitting system, but little difference in those of green emitting system. 2. There was no difference in the size of phosphor particles between the front and back screen for each screen. However, the particle size was different for the various kinds of screens. 3. The shape of phosphor particle was round with many faces for all the screens. 4. In the exposure of X-ray with the same intensity, luminescent intensity of a green emitting system was $6{\sim}7$ times larger than that of a blue emitting system. 5. The thickness of phosphor layers does not affect on the sensitivity of the screens exposed by X-ray.

• Korean System Dynamics Review
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• v.10 no.2
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• pp.5-27
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• 2009

Multiplex is a representative culture facility of citizens. Therefore, a lot of researches and investment on multiplex are carried out to improve benefits of service suppliers and users. Especially, focused on main services of a theatre such as ticket booking and issuing within multiplex, examination of tickets, admission information of movie screens and screening information inquiry, improvement activities are carried out. However, it is not enough to evaluate on what efficiency the above efforts have in the viewpoint of customer benefits and business. Therefore, this study analyzed value and limit of the newest service of multiplex applying the existing ubiquitous concept(u-multiplex service), and proposed a model and a plan for improving the existing services. The study interviewed with specialists in the related field and applied workshop-shape group interview to 110 university students and simulated service models. The contribution of the study is to analyze the value and limit of the existing multiplex service objectively, and to propose a new service model and plan to improve its limitation. In the future, the study plans to research on service models by extending space and functional roles of multiplex to the whole subsidiary facilities including movie screens.

• Fire Science and Engineering
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• v.18 no.2
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• pp.73-78
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• 2004

This study investigated about smoke/heat interception screen that can protect underneath of fire door and floor when occur fire, and keep out leakage or diffusion of smoke/heat. In this study, to considered differential pressure form smoke control area and mechanical force by fluid buoyancy of smoke when occur fire and stream of heat, are analyzed to used $ANSYS^{\circledR}$ of finite element analysis code. It presented direction of optimal design of smoke/heat interception screens that can minimize loading condition from study results, and helped that construct basic engineering data of smoke/heat interception systems as that utilize its shape design of smoke/heat interception screens.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.274-284
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• 1991

Mean flows and Reynolds stresses through circular and elliptic wire-mesh screens in the wind tunnel are measured by using the hot-wire system, and flow structures are investigated. Flow in the core of the wake are nearly uniform and the shear layer is developed along the edge of the screen The turbulent kinetic energy in the core decreases at the fast rate. However turbulence components are not in local equilibrium in the shear layer. The shear layer of the circular screen develops outward according to the radial mean motion. On the other hand, 3-dimensional transverse mean motion was turned to the main mechanism for the elliptic shape of the wake to be circular at the downstream.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.177-185
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• 2018

There is a need to study dust separator screens with good drainage efficiency while effectively filtering suspended solids and other contaminants entering the intake pumping station, the drainage pumping station and the mediation pumping station, the cooling water inlet of the power plant, and the like. In this paper, Numerical studies were conducted for the optimal design of the dust separator screen using the Coanda effect. The shape of the dust separator screen is important, such as the right curvature radius $R_1$ at the top of the dust separator screen and the left curvature radius $R_2$ at the top, h is the height difference and shape between the screen and the accelerating plate, and ${\theta}$ is the inclination angle of the screen. A total of 4 shape factors were set and the effects of Coanda and drainage performance of each element were compared and analyzed, the optimum length and size of each shape element were derived by classifying the shape elements into direct and indirect influences. Finally, it was possible to effectively filter foreign matter by narrowing the screen spacing, and the drainage performance was analyzed and optimized through numerical studies of dust separator screen.