• Annual Conference of KIPS
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• 2000.10b
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• pp.1597-1600
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• 2000

현재의 무선 이동통신은 음성통화를 위주로 설계되어 사용되고 있다. 그러나 차츰 인터넷 접속과 같은 데이터 통신 요구가 증대되고 있으며, 특히 이미 가시화된 IMT-2000과 4세대 이동통신망이라 할 수 있는 ALL-IP 망에서는 동영상을 포함한 멀티미디어 서비스에 대한 욕구를 수용하기 위한 연구가 활발히 진행되고 있다. 본 논문에서는 유선 구간에 비해 자원의 제약이 큰 무선 구간에서의 효율적인 자원 할당을 위한 QoS(Qualify of Service) 협상자를 설계하였다. 협상의 전제가 될 수 있는 서비스 등급을 대역폭 할당의 가변 여부에 따라 세 등급으로 분류하였으며, 협상 에이전트는 이 정보들을 기반으로 요구 대역폭과 서비스 종류에 따라 협상을 통해 대역폭 할당량을 정의한다. 이에 따라 QoS 관리자가 적절한 자원을 할당하게 함으로써 전체적인 무선자원의 활용도를 높이도록 하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.613-616
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• 1999

An active-matrix LCD using thin film transistors (TFTs)has been widely recognized as having potential for high-quality color flat-panel displays. Pixel-Design Array Simulation Tool (PDAST) was used to profoundly understand the gate signal distortion and pixel charging capability, which are the most critical limiting factors for high-quality TFT-LCDs. Since PDAST can simulate the gate data and pixel voltages of a certain pixel on TFT array at any time and at any location on an array, the effect of the new set of capacitance models on the pixel operations can be effectively analyzed, The set of models which is adopted from VLSI interconnections calculate more precise capacitance. The information obtained from this study could be utilized to design the larger area and finer image quality panel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.4
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• pp.311-316
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• 2003

Effects of pores on the microwave properties in microwave dielectric ceramics were studied by a computer simulation. Scattering matrix S$\_$21/ obtained from the network analyzer was compared to the S$\_$21/ obtained from the simulation. From electric field distribution, the dominant resonant TE$\_$01$\delta$/ mode could be easily determined. The effects of the porosity and pore size inside the dielectrics on the microwave properties were investigated by the HFSS simulation. When the total pore volume remains constantly, the quality factor decreased as the pore size Increases. As the total pore volume of the dielectrics increased. quality factor decreased.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.250-252
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• 1999

It is certain that the power qualify will be very important at 21 century. Especially instant power shortage or power fault will occur serious problems. Accordingly stable power supplication is very technical problem. There are many way to make stable supplication as auxiliary generator, but this is long time delay complement. To solve this problem the superconducting magnetic energy storage is introduced. High Tc superconductor is more commercial.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2026-2028
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• 2000

As the results of evaluation of its performance for 300 kN Ball and Socket type suspension insulators. There was electrically internal puncture of the solid insulating body of the insulating due to the steep front impulse voltage, which usually occurs puncture before external flash-over of insulators, moreover we have obtained satisfactory results in power arc test of 7.2kA cycle fatigue test with high qualify control index of 4.6, especially we have obtained more satisfactory results than that before improvement of its materials.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.246-249
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• 2003

For quite a long time various researches and developments of superconducting magnetic energy storage(SMES) device for enhancement of power qualify control of sensitive electric load. This paper describes the design, fabrication and experimental results for the 3MJ SMES magnet made by using the design code of a SMES device that we developed. A computer code was developed to find the parameters of the SMES magnet which has minimum amount of superconductor for the same stored energy, and the 3MJ SMES magnet was designed based upon that. And 3MJ SMES magnet made base of several research result which was ramp up to 1㎄ without quench.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.151-153
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• 2003

This paper was studied on using data of the protective relay by Power Quality Monitor. The protective relay will have problem to save data for PQM(Power Qualify Monitoring) analysis because the protective relay memory is limited. So this paper was proposed new data compression of the data was get from the protective relay. The scheme is compared each cycle after DFT(Discrete Fourier Transform). And scheme is verified through simulation of protective relay data was from real distribution system.

• Computers and Concrete
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• v.3 no.2_3
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• pp.145-161
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• 2006

This article involves architecting prototype-fuzzy expert system for designing the nominal cover thickness by means of fuzzy inference for quantitatively representing the environment affecting factor to reinforced concrete in chloride-induced corrosion environment. In this work, nominal cover thickness to reinforcement in concrete was determined by the sum of minimum cover thickness and tolerance to that defined from skill level, constructability and the significance of member. Several variables defining the quality of concrete and environment affecting factor (EAF) including relative humidity, temperature, cyclic wet and dry, and the distance from coast were treated as fuzzy variables. To qualify EAF the environment conditions of cycle degree of wet-dry, relative humidity, distance from coast and temperature were used as input variables. To determine the nominal cover thickness a qualified EAF, concrete grade, and watercement ratio were used. The membership functions of each fuzzy variable were generated from the engineering knowledge and intuition based on some references as well as some international codes of practice.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.6
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• pp.111-117
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• 2002

The high quality and a nearly stoichometric growth of $Cd_{1-y} Zn_y$/Te(y＝0.04) epilayers have been successfully grown on GaAs substrate by hot wall epitaxy (HWE) by optimizing the growth condition including the preheating treatment and Cd reservoir temperature. The relationship between quality and thickness was examined and best value of FWHM from X-ray rocking curve of 121 arcsec are obtained. Also, emission peaks related to the recombination of free excitons such as the ground state and the first excited state were observed in the PL spectrum at 4.2K. The ($A^0$, X) emission related to Cd vacancy and deep level emission was not measured. These results indicated that the grown CZT/GaAs epilayer was high qualify and purity.

• Proceedings of the Safety Management and Science Conference
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• 2007.04a
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• pp.399-415
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• 2007

In spite of the development of the service industry, research on measuring customers' service satisfaction is far insufficient. Therefore, ways to measure the service qualify accurately need to be established due to the ambiguous types of service business. This research classifies the types of service business into service factory, service shop, mass service, professional service by using Schmenner's Service Process Matrix and conducts research on domestic literature that measured service satisfaction with Servqual and ServPerf. This study intends to suggest guidelines to measure customer satisfaction according to types of service business by researching ways to measure service satisfaction according to the types of service business and analysing the actual application methods based on a table that summarizes previous research on Servqual and Servperf.