• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.12
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• pp.1821-1830
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• 2001

The flow around free end of a finite circular cylinder (FC) embedded in an atmospheric boundary layer has been investigated experimentally. The experiments were carried out in a closed-return type subsonic wind tunnel with varying aspect ratio of the finite cylinder mounted vertically on a flat plate. The wakes behind a 2-D cylinder and a finite cylinder located in a uniform flow were measured for comparison. Reynolds number based on the cylinder diameter was about Re=20,000. A hot-wire anemometer was employed to measure the wake velocity and the mean pressure distributions on the cylinder surface were also measured. The flow past the FC free end shows a complicated three-dimensional wake structure and flow phenomenon is quite different from that of 2-D cylinder. The three-dimensional flow structure was attributed to the downwashing counter rotating vortices separated from the FC free end. As the FC aspect ratio decreases, the vortex shedding frequency decreases and the vortex formation length increases compared to that of 2-D cylinder. Due to the descending counter-rotating twin-vortex, near the FC free end, regular vortex shedding from the cylinder is suppressed and the vortex formation region is hardly distinguished. Around the center of the wake, the mean velocity for the FC located in atmospheric boundary layer has large velocity deficit compared to that of uniform flow.

• Journal of the Korea Society of Computer and Information
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• v.12 no.2 s.46
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• pp.299-305
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• 2007

This thesis will show the preparation of politic alternative plan about reaction through studying the domestic and overseas research trend and theories about online games analyzing the related problems. Online games have been already placed as the major culture trend in our society and produced the economic wealth as the major theme of 'Korean trend hot wind', including improvement of our foreign confidence. And the investments in online games and related industry are expected to be great Blue Ocean to us to have relatively deficient endowed resources. But with these beneficial effects, many unexpected reactions have happened and often published by medias, and they will be expected to be serious. So, it is to establish the united solution system of disputes related to online games which are spread in each law. Through this, we must draw prevention effects and use that as the evidence of rational judgements. And we must make the base to give online games the opportunity of upgrading to national strategic industry and try to conduct the research in various fields between academic organizations.

• Atmosphere
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• v.24 no.2
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• pp.245-251
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• 2014

Statistical trajectory analysis has been widely used to identify potential source regions for chemically and radiatively important chemical species in the atmosphere. The most widely used method is a statistical source-receptor model developed by Stohl (1996), of which the underlying principle is that elevated concentrations at an observation site are proportionally related to both the average concentrations on a specific grid cell where the observed air mass has been passing over and the residence time staying over that grid cell. Thus, the method can compute a residence-time-weighted mean concentration for each grid cell by superimposing the back trajectory domain on the grid matrix. The concentration on a grid cell could be used as a proxy for potential source strength of corresponding species. This technical note describes the statistical trajectory approach and introduces its application to estimate potential source regions of $CO_2$ enhancements observed at Korean Global Atmosphere Watch Observatory in Anmyeon-do. Back trajectories are calculated using HYSPLIT 4 model based on wind fields provided by NCEP GDAS. The identified $CO_2$ potential source regions responsible for the pollution events observed at Anmyeon-do in 2010 were mainly Beijing area and the Northern China where Haerbin, Shenyang and Changchun mega cities are located. This is consistent with bottom-up emission information. In spite of inherent uncertainties of this method in estimating sharp spatial gradients within the vicinity of the emission hot spots, this study suggests that the statistical trajectory analysis can be a useful tool for identifying anthropogenic potential source regions for major GHGs.

• Journal of Sasang Constitutional Medicine
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• v.13 no.2
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• pp.124-137
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• 2001

The purpose of this research was to investigate the inhibitory function among foods and herb drugs. I have gone over literatures of mainly ${\ll}$Eum-Sun-Jung-Yo(飮膳正要)${\gg}$ on the basis of ${\ll}$Dong-Eui-Bo-Gam (東醫寶鑑)${\gg}$ about the properties and flavors of foods and herb drugs. And then I came to get some conclusion as follows. 1. The foods mentioned above are meats, birds, fishes, spices and vegetables. 2. If the foods mentioned above were eaten for a long time, and then it can cause stirring Wind or Qi or Fire inside the body. 3. What it means in the context of the chapter ${\ulcorner}$Sik-Mul-Sang-Ban : Inhibitory Function Among Foods and Herb Drugs(食物相反)${\lrcorner}$ that 'Do not eat the paired foods or herb drugs at a same time' and 'Do not eat the paired foods or herb drugs together for a long time.' 4. The Cold natured foods were not eaten at a same time. 5. The Hot or Warm natured foods were not eaten at a same time. 6. The contrary natured foods were not eaten at a same time. Because they were eaten at a same time, it raise a Occurrence of Cold and Heat syndromes and a Qi disorder.

• Journal of Korean Association for Spatial Structures
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• v.17 no.2
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• pp.21-32
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• 2017

The objective of this study is to analysis the mechanical characteristics on the geometric nonlinear behavior of radial cable roof systems for long span retractable cable roof structures. The retractable roof is designed as a full control system to overcome extreme outdoor environments such as extreme hot or cold weather, strong wind or sunlight, and the cable roof greatly can reduce roof weight compared to other rigid structural system. A retractable cable roof system is a type of structures in which the part of entire roof can be opened and closed. The radial cable roof is an effective structural system for large span retractable roofs, the outer perimeter of the roof is a fixed membrane roof and the middle part is a roof that can be opened and closed. The double arrangement cables of a radial cable truss roof system with reverse curvature works more effectively as a load bearing cables, the cable system can carry vertical load in up and downward direction. In this paper, to analyze the mechanical characteristics of a radial cable roof system with central posts, the authors will investigate the tensile forces of bearing cables, stabilized cables, ring cables, and the deflection of roof according to the height of the post or hub that affects the sag ratio of cable truss. The tensile forces of the cables and the deflection of the roof are compared for the cases when the retractable roof is closed and opened.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.99.2-99.2
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• 2012

We updated the far-ultraviolet (FUV) spectral images of the entire Vela supernova remnant (SNR) using newly processed FIMS/SPEAR data. In the present study, we compare the newly produced FUV images with the X-ray and $H{\alpha}$ images, and examine how the Vela SNR evolves and interacts with the ambient medium on a global scale. The comparison with X-ray images has revealed a FUV filamentary feature corresponding with the boundary of the northeast-southwest asymmetry of the X-ray shell. The relatively low O IV] ${\lambda}1404$ to O III] ${\lambda}{\lambda}1661$, 1666 ratio estimated on the FUV filament is compatible with the previous proposal that the observed asymmetry of the Vela SNR could be due to the ${\gamma}2$ Velorum stellar wind bubble (SWB). The southwest FUV features surrounding a faint extended X-ray region are characterized as the region where the Vela SNR is interacting slightly stronger with ambient mediums within the dim X-ray southwest section. From a comparison with the $H{\alpha}$ image, we identify a ring-like $H{\alpha}$ feature overlapped with an extended hot X-ray feature of similar size and two local peaks of C IV ${\lambda}{\lambda}1548$, 1551 emission. Their morphologies are consistent with the expected shape when the $H{\alpha}$ ring is in direct contact with the near or far side of the Vela SNR. We suggest that the B3V-type star HD 76161 found at the center of the $H{\alpha}$ ring would be the exciting source of the H II region.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.6
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• pp.75-80
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• 2013

In this study, a forced ignition method with a plasma jet torch is studied in Mach 2 laboratory scaled wind-tunnel. The hyper-mixer is used as a mixer. For two normal injection cases, the one is collided against a wedge plate of the hyper-mixer and the other is directly injected into the cold main flow. For the first case, the hyper-mixer disperses the injected fuel, leading to the mixing enhancement. Furthermore, the fuel-air mixture is provided into the plasma hot gas, which enhances the combustion performance. However, the direct injection into the main flow method spends amount of fuel without ignition in the cold supersonic flow. In the end, for the forced combustion, it is important to supply the fuel-air mixture into the heat source.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.14 no.2
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• pp.207-223
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• 2001

The Wonyenaejang is equivalent to the (senile)cataract in western medicine. The word cataract is used to describe the natural lens that has turned cloudy. As the natural lens of the eye becomes cloudy, it does not allow light to pass through it. Cataracts usually start as a slight cloudiness that progressively grows more opaque. As the cataract becomes more mature(increasingly opaque and dense), the retina receives less and less light. The light that does reach the retina becomes increasingly blurred and distorted. This causes gradual impairment of vision. If left untreated, cataracts can cause needless blindness. Although there are many kinds of cataracts, a senile cataract is the most common one. We chose the oriental medicine textbooks and the oriental medicine journals that were dealing with the symptoms, etiology, and internal/external treatments. The results were as follows : 1. The main causes of this disease are weak liver and kidney, burning up of the wind and heat in the liver and gall, weak spleen and stomach. 2. As the internal treatment of the Cataract, Geegukjihwangtang is mostly prescribed. 3. As the external treatment of the Cataract, (l) In the field of medicine for external application is commonly prescribed (2) In the field of drug action, frequently used treatments are as follows. emission of the evil, alleviation of fever, removal of lump of blood, and the medicine for external applications. (3) In the field of four Qi, cold medicine is commonly prescribed. (4) In the field of five tastes, bitter/hot/sweet mdicine are commonly prescribed. (5) In the field of toxicity, non-togic medicine is commonly prescribed. (6) In the field of channel distribution, most of the medicine belong to liver channel.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.121-129
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• 2021

In addition to yellow dust occurring in China, fine dust has become a hot topic in Korea through news and media. Although there is fine dust generated from the outside, the purchase rate of air purifier products is increasing as external fine dust flows into the inside. The air purifier uses a filter internally, and the sensor notifies the user through the LED alarm whether the filter is replaced. However, there is currently no product measuring how much the filter rate is reduced and determining the pressure of the blower to operate. Therefore, in this paper, data are generated directly using Arduino, fine dust sensor, and differential pressure sensor. In addition, a program was developed using Python programming to calculate how old the filter is and to analyze the wind power of the blower according to the filter rate by calculating the measured dust and pressure values.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.8
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• pp.23-34
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• 2019

The façade, a fundamental function as a skin that protects human life from external environment such as cold and hot weather, snow, rain, and wind, etc, has served as a media for communication between indoor space of the building and outside space. From the media for communication point of view, the approach to envelope design, in which environmental elements are transmitted internally through the filtering of external environments, has been evolving in various ways from the past to the present. Today, modern architecture technologies including curtain wall systems and user-friendly computer programming and environmental analysis programs demonstrate a differentiated approach to envelope design related to the indoor environment. For this reason, it is worth noting that the envelope design factors and trends that appear variously in the UNStudio's projects before and after the 2000s. The factors reflected in the envelop design in conjunction with the indoor environment obtained through the case study of the UNStudio's office projects were daylight environment, thermal environment, ventilation, noise, privacy and view, and consideration for daylight environment and thermal environment was reflected in many cases through the case study. Looking at the changes in the diagrams in order of year, it can be seen that the envelope design using the environmental analysis tool has been performed since 2006. This is a clue to show the envelop design changes from the conceptual method to the data-based one. The diagrams and analysis results related to the envelop design showed that the thermal environment related to solar radiation was the most, and no diagrams and analysis related to the indoor illumination were found. Since 2010, PV panel installation has been shown in the envelope design, which can be found in the increased efficiency of PV panels due to the technological advances and the decrease in production cost.