• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.11
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• pp.1087-1093
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• 2010

The satellite thermal control H/W composed of two parallel channels working for heat pipe (HP) and phase change material (PCM) is suggested for the high heat dissipating component which works intermittently with short duty. In a limited point of view, the HP-PCM device is a kind of off-the-shelf component that requires no dedicated configuration and thermal designs to PCM. Therefore, it can be used with less impact on the program cost and schedule different from most of the PCM applications. In present study the typical honeycomb structure radiator applying the HP-PCM device is designed and the detail thermal math model is developed for numerical analyses. The result comparison between without and with PCM shows that the HP-PCM device redistributes the peak heat around the whole mission period through the alternate melting and freezing of PCM, and, as a result, the maximum and minimum temperatures are effectively alleviated. The drawback of PCM application due to low thermal conductivity can be successfully resolved by means of parallel arrangement of HP channel.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.3
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• pp.397-404
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• 2011

In this research, wish to suggest method to embody system that can accommodate defect of PLC and find actual propriety. Defect permission control system minimizes production damage because enables repair and checking without discontinuance and improve believability about whole system. Propose duplexing of system to embody this fault tolerant system. Therefore, composed control system that can permit defect or breakdown duplexings of various module proposing this system, and confirms to simulation and actuality kiln of defect permission control system through an application experiment, and compares for mean time between defect by estimate and defect special quality and system configuration of failure(failure) to improve believability of PLC control system together. In proposed system expression method and system mode and relation with operation mode, error discovery mode and switching tube of duplexing mode, and PLC's central processing unit of node study algorithm about master-standby conversion driving and continuous operation of 2 channels method that have 2 that is not one and deduced continuous operation method and result about defect permission in this algorithm and applies this result to actuality kiln control system and confirms continuous operation about PLC defect permission.

• Journal of Power Electronics
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• v.5 no.3
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• pp.233-239
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• 2005

In this paper, a new conceptual circuit configuration of a 3-phase voltage source, soft switching AC-DC-AC converter using an IGBT module, which has one ARCPL circuit and one ARDCL circuit, is presented. In actuality, the ARCPL circuit is applied in the 3-phase voltage source rectifier side, and the ARDCL circuit is in the inverter side. And more, each power semiconductor device has a novel clamp snubber circuit, which can save the power semiconductor device from voltage and current across each power device. The proposed soft switching circuits have only two active power semiconductor devices. These ARCPL and ARDCL circuits consist of fewer parts than the conventional soft switching circuit. Furthermore, the proposed 3-phase voltage source soft switching AC-DC-AC power conversion system needs no additional sensor for complete soft switching as compared with the conventional 3-phase voltage source AC-DC-AC power conversion system. In addition to this, these soft switching circuits operate only once in one sampling term. Therefore, the power conversion efficiency of the proposed AC-DC-AC converter system will get higher than a conventional soft switching converter system because of the reduced ARCPL and ARDCL circuit losses. The operation timing and terms for ARDCL and ARCPL circuits are calculated and controlled by the smoothing DC capacitor voltage and the output AC current. Using this control, the loss of the soft switching circuits are reduced owing to reduced resonant inductor current in ARCPL and ARDCL circuits as compared with the conventional controlled soft switching power conversion system. The operating performances of proposed soft switching AC-DC-AC converter treated here are evaluated on the basis of experimental results in a 50kVA setup in this paper. As a result of experiment on the 50kVA system, it was confirmed that the proposed circuit could reduce conduction noise below 10 MHz and improve the conversion efficiency from 88. 5% to 90.5%, when compared with the hard switching circuit.

• Korean Institute of Interior Design Journal
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• v.25 no.3
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• pp.70-81
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• 2016

Nowadays the preschool children spend much of the day playing indoors. Therefore, it needs the indoor environment that helps a variety of fun activities and physical development, and it requires the space configuration and playable furniture considering the emotional development for mental health. However, the furniture for fast growing preschoolers has not various types because the domestic furniture market for children is mostly baby beds and the furniture for the education of children. Therefore, this study presents the concepts and types of the playable furniture reflecting emotional design for preschool children's healthy emotion and suggests the most appropriate type of playable furniture considering play behavior by age. In this study, we investigated the physical, cognitive, social, emotional and linguistic development characteristics and play behavior of preschoolers, and derived the right type of playground equipment and furniture, and examined the types of playable furniture to help the emotional development. We derived the items to be checked for developing the playable furniture by age for emotional development, and classified preschoolers' playable furniture into the use of learning, relaxation and storage, and suggested its basic type focusing on the cases of various playable furniture developed at home and abroad. As a result, the playable furniture was divided into three types. The first is the self-play type making possible self amusement, the second is module built-up-type that consists of furniture and modules or units and creates various patterns and can be modified through the self-assembly and disassembly, and the third is IT game type grafting IT skills and a variety of electronic games to furniture. We sorted these types into three classes (1-3 years old, 4-5, 6-7) according to age and presented the type of play for each age, the play element and representative image that can be introduced to this furniture. In this study, we provided the basic design types of age-specific emotional playable furniture by analyzing these results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.943-946
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• 2006

XML is the most widely used document format by advantage that self-contained for platform. So, currently the most used among other document format. but XML appeared new problem that memory and transmission. And that be used in environment a request restriction memory and fast transmission as like mobile field. Although discussion of XML binarization is going on progress. And fast Infoset configuration using XML Information Set is receiving attention that a way to lower file size of hold down a existing usage. In this paper, we designed of module using fast Infoset and PER among ASN.1 Encoding Rule for XML binarization. And we implementation of encoder constructed interlace by stage of translation from XML into binary XML.

• The KIPS Transactions:PartC
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• v.15C no.4
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• pp.311-320
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• 2008

In general, routing algorithms that were applied to ad-hoc networks are not suitable for the environment with many nodes over several thousands. To solve this problem, hierarchical management to these nodes and clustering-based protocols for the stable maintenance of topology are used. In this paper, we propose the clustering-based modified LEACH protocol that can applied to an environment which moves around metal containers within communication nodes. In proposed protocol, we implemented a module for detecting the movement of nodes on the clustering-based LEACH protocol and improved the defect of LEACH in an environment with movable nodes. And we showed the possibility of the effective communication by adjusting the configuration method of multi-hop. We also compared the proposed protocol with LEACH in four points of view, which are a gradual network composition time, a reconfiguration time of a topology, a success ratio of communication on an containers environment, and routing overheads. And to conclude, we verified that the proposed protocol is better than original LEACH protocol in the metal containers environment within communication of nodes.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.81-88
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• 2019

Since the AESA radar scans and tracks a distant targets or ground, it requires a test field which meets far-field condition before flight test. In order to test beam foaming, targeting, and availability from cluttering and jamming, it is general to build a outdoor roof-lab test site at tens of meters high. However, the site is affected by surrounding terrain, weather, and noise wave and is also requires time, space, and a lot of costs. In order to solve this problem, theoretical near-field beam foaming method has proposed. However, it requires modification of associated hardware in order to construct near-field test configuration. In this paper, we propose near-field beam foaming method which use single LUT in order to calibrate the variation of TRM(transmit-receive module) which consists AESA radar without modification of associated hardware and software. It requires less costs than far-field test and multiple LUT based near-field test, nevertheless it can derives similar experimental results.

• Journal of the Korea Computer Graphics Society
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• v.25 no.3
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• pp.65-73
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• 2019

Recently commercial mixed-reality devices have be launched and a variety of mixed-reality content has produced, but narrow field of view, which appear to be hardware technical limitations, are mentioned as an important issue for hindering immersion and limiting the scope of use. We propose a new innovative system that cooperate multiple beam projectors and a number of mixed reality devices. Using this technology, users can maximize immersion and minimize frustration of narrow viewing angles through 3D object rendering on background of large 2D screens. This system, named BtS (Beyond the Sight), is implemented on a client-server basis and includes the ability to calibrate between devices, share spatial coordinate systems, and synchronize real-time renderings as core modules. In this paper, each configuration module is described in detail and the possibility of its performance and application is shown through the introduction of mixed reality content case created using BtS system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.639-642
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• 2014

If the power of the general is not supplied, Visual aids utilize solar power system. The power supply system of these, the role of the power regulator to manage the charging and discharging is very important. In recent years, by introducing the IT technology for the effective management of visual aids, it was supposed to add a device that uses the power consumption. Thus, the importance of power regulator has increased. Currently, the power regulator is installed inside the AtoN, if the accessibility is not ensured, there is a difficulty that can not be checked. In order to solve these problems, in this paper, you have installed the Blue-tooth module to the power regulator. Also, by using the Blue-tooth communication function of a smart phone, a radio check has implemented a possible monitoring system. Advantage of the system implemented is a simple configuration and low installation cost. Also, it is possible to check the state information of the real-time power supply regulator. In addition, it has the effect of preventing accidents and reducing costs of inspection.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.942-943
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• 2016

Stereo gamma ray detection system generates a two-dimensional image of the gamma ray by using the position values and the gamma ray signal. And the device will overlap with the visible light image shows the actual distribution of the gamma-ray space. The gamma ray detection device is a stereo configuration to a motion controller for controlling the signal measurement unit and the position detection portion for detecting the detection portion and the gamma-ray signal comprising a gamma-ray detection sensor. In this paper, we developed a system operation management algorithm for each module individually configured efficiently. We confirmed the imaged and distribution information output for the gamma rays from gamma-ray irradiation test site by using these results.