• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.3
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• pp.253-262
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• 2007

Although the importance of good conservation of historical sites including ancient royal tombs is well aware, still not much attention has been paid for facilities to realize it. There are numerous ancient royal tombs spread in Korean peninsula which are opened and some of them are selectively on display for public access. However, the conservation measures of these sites have not been seriously investigated. Even the level of understanding of the underground environment of tombs is not satisfactory. In the present study, we focus on the dehumidification loads to maintain appropriate conservation conditions in terms of temperature and humidity. Two experimental tombs different in size were built in KNU (Kongju National University) campus with the dimensions ($L{\times}W{\times}H$) of $1.0m{\times}2.8m{\times}1.0m\;and\;1.3m{\times}3.0m{\time}1.2m$, respectively, HVAC systems are installed to maintain a suitable condition for conservation, i.e., $22{\pm}2^{\circ}C$ in temperature and $55{\pm}5%$ in relative humidity. The condensed water are measured to estimate the dehumidification loads while the temperature and the humidity inside the tombs were maintained within the specified range.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1849-1856
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• 2010

Glass/resin/glass laminate structures are used in the automobile, biological, and display industries. The sandwich structures are used in the micro/nanoimprint process to fabricate a variety of functional components and devices in fields such as display, optics, MEMS, and bioindustry. In the process, micrometer- or nanometer-scale patterns are transferred onto the substrate using UV curing resins. The demodling process has an important impact on productivity. In this study, we investigated the fracture behavior of glass/resin/glass laminates fabricated via UV curing. We performed measurements of the adhesion force and the interfacial energy between the mold and resin materials using the four-point flexural test. The bending-test measurements and the load-displacement curves of the laminates indicate that the fracture behavior is influenced by the interfacial energy between the mold and resin and the resin thickness.

• Journal of the Semiconductor & Display Technology
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• v.4 no.1 s.10
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• pp.43-48
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• 2005

Metaloganic chemical vapor deposition, also known as metalorganic vapor phase epitaxy has become one of the main techniques for growing thin, high purity films for compound semiconductors such as GaAs, InP, and InGaAsP. In this study, the distribution of growth rate and composition of InGaAsP, InGaP, and InGaAs films are studied using computational method. The influences of process parameters such as pressure, temperature and precursors' partial pressure on the growth rate and composition distributions are analyzed. The film growth rate is increased in the upstream part according to the increase of temperature but not in the downstream part. The Ga composition in InGaAsP film shows an asymptotic behavior for temperature variation but As composition varies significantly within the temperature range considered in the present study. The overall film growth rates of InGaP, InGaAs and InGaAsP are decreased with increasing the Ga/In ratios of the source gases. Pressure variation does not seem to be a significant parameter to the film growth. Film growth characteristics of tertiary films such as InGaP and InGaAs show similar trends to the quaternary film, InGaAsP.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.141-149
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• 2013

Recently, the time in which children moves by car become frequent, they stay longer in the car because leisure life including camping and etc. increased. Children whose physical activities are active were subject to restriction because of the limited car boarding visual space and on security. Because of limited space in cars, domestic and foreign automotive companies show the different glass roof applied in cars that exhibited wide clear view in order to remove tedious and stuffy of children while they stay for a long time inside the car. In addition, the potential probability in which the Smart Car that the IT technology is grafted research and research that it utilizes the door window glass as the display is progressed and which the glass roof can be used as the screen can be sufficient. In this study, the in-vehicle display application case and Smart Devices constellation application were benchmarked. The car glass roof application method of the constellation studying content which performed the user survey for the child by the car with the parents whose movement is frequent and considers the child and fundamental interaction way tried to be drawn and we try to propose.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.12
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• pp.23-30
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• 2009

LEDs are increasingly used for many applications including automotive, aviation, display, transportation and special lighting applications. Generally, the RGB multichip LED luminaire applied to signboard, emotional lighting system and display device and the white LED luminaire applied to general lighting system. white LED spectra for general lighting should be designed for high luminous efficacy as well as good color rendering. This paper describes characteristics of LED luminaire white LED and RGB multichip LED. Two type of LED luminaire prototype used experiment physical, electrical and optic test and performance analyzed. RGB multi-chip and phosphor-type white LED luminaire were analyzed by experiment on their color characteristics and luminous efficacy of radiation, distribution curve, and electrical characteristics. Research work is in progress to develop an improved performance for optic and electrical works well for two type of LED luminaires.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.1-5
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• 2024

In the electronics industry, a lot of research and development is being conducted on electronic component supply, component alignment and insertion, and automation of soldering on the back side of the PCB for automatic PCB assembly. Additionally, as the use of electronic components increases in the automotive component field, there is a growing need to automate the alignment and insertion of components with leads such as transistors, coils, and fuses on PCB. In response to these demands, the types of PCB and parts used have been more various, and as this industrial trend, the quantity and placement of automation equipment that supplies, aligns, inserts, and solders components has become important in PCB manufacturing plants. It is also necessary to reduce the pre-setting time before using each automation equipment. In this study, we propose a method in which a vision system recognizes the type of component and simultaneously corrects alignment errors during the process of aligning and inserting various types of electronic components. The proposed method is effective in manufacturing various types of PCBs by minimizing the amount of automatic equipment inserted after alignment with the component supply device and omitting the preset process depending on the type of component supplied. Also the advantage of the proposed method is that the structure of the existing automatic insertion machine can be easily modified and utilized without major changes.

• The Journal of Information Systems
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• v.26 no.2
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• pp.105-121
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• 2017

Purpose It is a major goal to improve the product yields during production operations in the manufacturing industry. Therefore, factory is trying to keep the good quality materials and proper production resources, also find the proper condition of facilities and manufacturing environment for yields improvement. Design/methodology/approach We propose the hybrid framework to analyze to dataset extracted from MES. Those data is about the alarm information generated from equipment, both measurement and equipment process value from production and cycle/pitch time measured from production data these covered products during production. We adapt a data warehousing techniques for organizing dataset, a logistic regression for finding out the significant factors, and a association analysis for drawing the rules which affect the product yields. And then we validate the framework by applying the real data generated from the discrete process in secondary cell battery manufacturing. Findings This paper deals with challenges to apply the full potential of modeling and simulation within CPPS(Cyber-Physical Production System) and Smart Factory implementation. The framework is being applied in one of the most advanced and complex industrial sectors like semiconductor, display, and automotive industry.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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• pp.37-44
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• 2013

Friction stir welding (FSW) is a solid state joining technique that has expanded rapidly since its development in 1991 and has numerous applications in a wide variety of industries. This paper introduces the basic principles of friction stir welding (FSW) and presents a survey of the latest technologies and applications in the field. The basic principles that are discussed include the terminology, tool/workpiece processes, FSW merits and process variants. In particular, the process variants including the rotation speed and traveling speed are discussed, which include the defect-free zone in an oxygen free copper and Al alloy, respectively. Multiple aspects of the FSW machine are developed, including a horizontal 2D FSW machine and a hybrid complex FSW machine. The latest applications are introduced, with an emphasis on the recent advances in the aerospace, automotive, and IT display industries. Finally, the direction for future research and potential applications are examined.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.778-784
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• 2012

In comparison with some other light sources, LED has merits such as increased life expectancy, fast response, pollution free, and high energy efficiency. Lately, due to development of LED with high brightness and capacity, LED has widely used in many industrial fields such as automotive, aviation, display, transportation and special lighting applications. Since the high heat generation of LED chips can cause a reduction in lifetime, degradation of luminous efficiency, and variation of color temperature, studies have been carried out on the optimization of LED packaging and heat sinks. In this study, experiments on measuring the heat generation rate of LED and the cooling performance of a heat sink were carried for analyzing the thermal characteristics of LED lighting system in free convection. From the results, dimensionless correlation on the cooling performance of heat sink in natural convection was proposed with Nusselt number and Rayleigh number as a guideline for designing cooling device of LED lightings.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.105-115
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• 2022

The platform for displaying cars has been changing with the times. From the popularity of paper media to the rise of computer graphics, the improvement of technology has brought more space and possibilities to the automotive industry. Yiming Zhong proposed the workflow of car configurator through Unreal Engine 4 to implement the basic functions of configuration in 2021, according to Yiming Zhong's final presentation, there is still room to improve the realism of graphics and functionality of the car configurator. Therefore, in this paper we propose to upgrade the car shaders and lighting environments according to the real-world physics and add multi-scenes switching function to car configurator. However the multi-scenes switching function also brings a large amount of data, which leads to the problem of display lag. At the end of the paper, we use the level of details(LOD) process to reduce the amount of data for real-time computing in Unreal Engine 4 and the increase of frames per second(FPS) values verifies the feasibility of our optimization solution.