• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.427-429
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• 1993

In this paper, GIS (Geographical Information System) for KODAS (Korea Distribution Automation System) will be presented. It has been developed to display the status of distribution power line facilities with background geographical map information (eg. address, street, railways and building) and provides various menu screen that can be handled easily. We will discuss computer system I/F between Host computer and GIS, DB structure for GIS and It's functions.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.30-43
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• 2014

The number of online video content distributors are rapidly increasing in N-screen environment. The purpose of this study is to analyze the business model of these distributors, especially Netflix and Hulu. Basis on STOF model, environmental domain, service domain, organization domain and financial domain of each company are analyzed and compared. This study finds that each company's business model had distinct characters in earlier stage. Netflix offered online and offline service in low cost, while Hulu offered up-to-date TV contents without fees. However, two companies' business models are getting similar. The result of this study shows that highly competitive environment and increasing content budget affect two companies to adopt similar business model to survive.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.509-526
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• 2015

The study investigated the N-Screen strategies of paid digital contents of foreign newspapers belonging to advanced companies: USA, United Kingdom, and Japan. This research employed the time to launch paid digital content business, whether or not to segment market, and 4p marketing mix strategies for analyzing the strategies. The results show that the strategies, starting around the year 2000, had experience chasm, and then revived since the year 2010, when the penetration rate of mobile devices proliferated. Most newspapers still supply contents under the assumption that they paly in a mass market. The items of paid digital contents are mainly composed of e-paper and digital contents. Regarding the price strategy, soft paywall and combination paywall are largely used. Distribution strategy is subject to whether or not to discriminate the path of digital contents. As for promotion strategy, bundling strategy with newspaper is mostly utilized. The difference between western countries and Japan was found in term of the free trial service.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2621-2627
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• 2023

In Experimental Advanced Superconducting Tokamak (EAST) experiments, to achieve long pulse and high-power ICRH system operation, a new kind of ICRH antenna has been designed. One of the most critical factors in limiting the operation of long pulse and high power is the intense heat load in the front face of the ICRH antenna, especially the Faraday Screen (FS). Therefore, the cooling channels of FS need to be designed. According to thermal-hydraulic analysis, the FS tubes are divided into several groups to achieve more excellent water cooling capability. The number of series and parallel tubes in one group is chosen as six. This antenna went into service in the spring of 2021, and it is delightful that the temperature distribution of the FS tube is below 400 ℃ in 14.5 s and 1.8 MW ICRH system operation. However, the active water-cooling design was not carried out on the upper and lower plates of FS, which led to severe ablations on that region under long pulse and high power operation, and the temperature is up to 800. Therefore, the upper and lower side plates of the FS were designed with water cooling based on thermal-hydraulic analysis. During the 2022 winter experiments, the temperature of ICRH antenna FS was lower than 400 in the pulse of 200s and the power of 1 MW operation.

• Journal of the Korea Society of Computer and Information
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• v.12 no.3
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• pp.235-241
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• 2007

The objective of this study plans on adopting the traceability system in domestic livestock production and marketing channels. This study will examine pork traceability system and investigate the problem and factor in domestic livestock production and marketing channels, and also to examine the international standard in traceability system of goods production and distribution and foreign traceability system. In this study, the traceability system of livestock products is defined as an ability to follow and trace the information about livestock product in the stage of production, processing, manufacturing, distribution, and marketing. The system of traceability for Meat products are Developed and managed that reflected situation of raising, marketing, gathering and of information of model farmers. The formation of system consists of surfing screen of consumers, registration of farming data by farmers, information input screen of gathering of meat products and supply of traceability information of production and gathering. The system should continue the system adjustment after checking effects and problems of traceability by surveying result of consumer, farmers and distributors.

• Journal of Sensor Science and Technology
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• v.17 no.6
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• pp.418-424
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• 2008

The PZT based piezoelectric thick films prepared by screen printing method have been mainly used as a functional material for MEMS applications due to their compatibility of MEMS process. However the screen printed thick films generally reveal poor electrical and mechanical properties because of their porous microstructure. To improve microstructure we mixed attrition milled powder with ball milled powder of 0.01Pb$(Mg_{1/2}W_{1/2})O_3$-0.41Pb$(Ni_{1/3}Nb_{2/3})O_3$-$0.35PbTiO_3$-$0.23PbZrO_3$+0.1 wt% ${Y_2}{O_3}$+1.5 wt% ZnO composition. By mixing 25 % of attrition milled powder and 75 % of ball milled powder, the broadest particle size distribution was obtained, leading to a dense thick film with crack-free microstructure and improved dielectric properties. The X-ray diffraction analysis revealed that the film was in wellcrystallized perovskite phase. The remanent polarization was increased from $13.7{\mu}C/cm^2$ to $23.3{\mu}C/cm^2$ at the addition of 25 % attrition milled powder.

• Journal of Mechanical Science and Technology
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• v.14 no.1
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• pp.121-129
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• 2000

The thermal performance of a flat evaporator for capillary pumped loop (CPL) applications was investigated. Two to four layers of coarse wire screen wicks were placed onto the heated surface to provide irregular passages for vapor flow. The evaporator and condenser were separated by a distance of 1.2 m and connected by individual liquid and vapor lines. The wall material was copper and the working fluid was ethanol. The experimental facility utilized a combination of capillary and gravitational forces for liquid return, and distribution over the evaporator surface. The tubing used for vapor and liquid lines was 9.35 mm or less in diameter and heat was removed from the condenser by convection of air. A heat flux of up to $4.9{\times}10^4$ $W/m^2$ was applied to a flat evaporator having dimensions of 100 mm by 200 mm, 20 mm thick. The thermal resistance of the system as well as the temperature characteristics of the system was investigated as the evaporator heat flux and the condenser cooling capacity varied. The performance of the evaporator and effect of condenser cooling capacity were analyzed and discussed.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.6
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• pp.31-35
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• 2013

This study was carried out to present the pressure drop for various wind speeds through nine types of screens used in horticultural facilities. The screens have been widely used to prevent harmful insects from being entered into agricultural facilities, to reduce strong wind and to shade a light as well. Whatever the usage of the screens was, it was necessary to have good knowledge of how much the screen caused a pressure drop for wind speeds when analyzing both the inner thermal-flow distribution in the facility and the effect of reducing wind speed by using CFD. Furthermore, as for wind screens, the pressure drop for wind speeds was needed as a design load in evaluating the structural stability of the structures supporting the screens. Therefore, the pressure drop through the screens for wind speeds of 5~30 $m{\cdot}s^{-1}$ at about 5 $m{\cdot}s^{-1}$ interval and inflow angles of $0{\sim}45^{\circ}$ at an interval of $15^{\circ}$ was respectively measured in a subsonic wind tunnel. The relation of the pressure drop for various screens was well fitted as a secondorder polynomial expression.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.12
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• pp.789-794
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• 2008

Recently, much attention has been paid in the field of defrosting because clear windshield in vehicle without effecting the thermal comfort is realized essentially. Then in winter, defrosting performance is one of the important factors in vehicle design to make certain driver's view. In this study, the velocity profile, temperature distribution and frost melting pattern on the windshield screen have been predicted in three dimensional geometry of an automobile interior. Numerical analyses predict a detailed description of fluid flow and temperature patterns on the inside windshield screen, utilizing the flow through defroster nozzle. Numerical prediction established a good defrosting performance with the standard distance ratio and the defroster nozzle angle ranging from $30^{\circ}$ to $40^{\circ}$, which satisfy the condition of National Highway Traffic Safety Administration (NHTSA) completely.

• Journal of Broadcast Engineering
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• v.9 no.2
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• pp.119-130
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• 2004

We have developed a prototype super-high-definition (SHD) digital cinema distribution system that can store, transmit, and display eight-million-pixel motion pictures that have the image quality of a 35-mm film movie. The system contains a movie server, a real-time decoder, and an SHB projector. Using a Gigabit Ethernet link and TCP/IP, the server transmits JPEG2000 compressed motion picture data streams to the decoder at transmission speeds as high as 300 Mbps. The received data streams are decompressed by the decoder, and then projected onto a screen via the projector. By using an enlarged TCP window, multiple TCP streams, and a shaping function to control the data transmission quantity, we achieved real-time streaming of SHD movie data at about 300 Mbps between Chicago and Los Angeles, a distance of more than 3000 km. We also improved the decoder performance to show movies with Image qualities of 450 Mbps or higher. Since UDP is more suitable than TCP for fast long-distance streaming, we have developed an SHD digital cinema UDP relay system, in which UDP is used for transmission over a fast long-distance network. By using four pairs of server-side-proxy and decoder-side-proxy, 450-Mbps movie data streams could be transmitted.