• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.54-56
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• 2005

QMS를 이용하여 chlorine based 유도결합 플라즈마 내 이온의 거동에 대한 분석을 하였다. 플라즈마 진단 가스로는 AT 가스에 $BCl_3$을 첨가하였으며 공정 압력을 변화하며 플라즈마 특성 변화를 분석하였다. 가스 혼합비에 따른 이온의 상대적인 밀도 변화에서 소량의 Ar가스의 첨가는 $BCl_3$ 가스의 이온화를 도와 $Cl^+$ 이온이 증가하는 현상을 보이며 Ar과 $BCl_3$의 이온화 에너지의 차이로 인해 $BCl_3$ 가스의 첨가비가 적을 수록, RF Power가 증가하며, 공정 압력이 낮올 수록 이중 피크 구조의 이온 에너지 분포를 확인 할 수 있었으며 이는 이온이 접지 전극에의 도달 시간과 평균 플라즈마 전위의 변화 때문이라고 사료된다.

• Genomics & Informatics
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• 제5권1호
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• pp.24-29
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• 2007

Computational virtual screening has become an essential platform of drug discovery for the efficient identification of active candidates. Moleculardocking, a key technology of receptor-centric virtual screening, is commonly used to predict the binding affinities of chemical compounds on target receptors. Despite the advancement and extensive application of these methods, substantial improvement is still required to increase their accuracy and time-efficiency. Here, we evaluate several advanced structure-based virtual screening approaches for elucidating the rank-order activity of chemical libraries, and the quantitative structureactivity relationship (QSAR). Our results show that the ensemble-average free energy estimation, including implicit solvation energy terms, significantly improves the hit enrichment of the virtual screening. We also demonstrate that the assignment of quantum mechanical-polarized (QM-polarized) partial charges to docked ligands contributes to the reproduction of the crystal pose of ligands in the docking and scoring procedure.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.873-876
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• 1999

Aspergillus sp. CX-l strain grown on microcrystalline cellulose resulted in the accumulation of high levels of cellulase and xylanase activities that were higher by two to four folds than those from the conventional commercial producer, Trichoderma reesei QM9414. Aspergillus sp. CX-1 demonstrated greater thermo stability and better catalytic characteristics of total cellulase activity (FPase) as compared to T. reesei and Aspergillus niger F-2039.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.438-441
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• 2001

In this study,microstructure and piezoelectric characteristics of PNW-PMN-PZT ceramics manufactured using attrition milling method were investigated. Sintering temperature of the ceramics was varied from $1180^{\circ}C$ to $1240^{\circ}C$.With increasing sintering temperature, dielectric constant was increased. In the specimen sintered at $1120^{\circ}C$,electromechanical coupling factor(Kp) and density showed the maxinum values of 0.546 and $7.78(g/cm^{3})$, respectively. In the specimen sintered at $1160^{\circ}C$,mechanical quality factor(Qm) also showed the maxinum value of 1,943.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.13-16
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• 1994

In this paper, xPb(Zn$_{1/3}Nb_{2/3}$)$O_3$-yPbTiO$_3$-zPbZrO$_3$-(0.5wt%)MnO$_2$ ceramics were fabricated by the mixed oxide method sintered at $1250^{\circ}C$ for 2[hr] and then the deielectric, electromechanical coupling factor($K_{p}$ and mechanical coupling factor(Qm) properties were investigated. In 0.1PZN-0.45PT-0.45PZsample, dielectric properties and electromechanical coupling factor were 829 and 29%. In the case of 0.5PZN-0.45PT-0.50PZ sample, that was 101 according to mechanical quality facotr. molphotropic phase boundary(MPB) certained area which $PbTiO_3$addition quatity 40∼50[㏖%].

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1025-1027
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• 1999

Recently, many researches on a diagnosis of stator winding insulation of large generators are reported. They mostly utilize a trend analysis of Partial Discharge (PD). In this paper, a novel on-line monitoring system for an insulation diagnosis is proposed. This system obtains the parameters such as Maximum Partial Discharge Magnitude (QM), Normalized Quantity Number (NQN) and Dynamic Stagnation Voltage (DSV) by continuous on-line monitoring of winding insulation. It is capable of diagnosing the insulation condition by analyzing the trend of PD and utilizing the database built by the system.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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• pp.95-99
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• 2004

장기수명특성 분포를 나타내는 제품의 유효수명 예측은 경험적인 Data와 현장정보만으로는 한계가 있으며, 이러한 한계를 극복하기 위해서는 초가속수명시험을 근거로 하는 유효수명예측이 반드시 필요한 상황이다. 그러나, 현장의 문제점은 이러한 사실을 바탕으로 하더라도 MTTF 혹은 MTBF, 심지어 Br수명분포까지도 제품 유효수명과의 상관관계가 어떻게 분포하는지에 관해 정확한 GUIDE LINE없이 적용하는 문제로 인하여 기업의 COPQ 부담이 증대하고 있다. 따라서 본 연구에서는 기업의 COPQ부담을 경감시키고, 제품의 유효수명예측의 정밀도를 향상하기 위한 대안으로서 HALT와 제품유효수명간의 상관관계를 규명하는데 주력하였다.

• 품질경영학회지
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• 제29권1호
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• pp.140-159
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• 2001

The purpose of this study is to analyse the effectiveness of Quality Leadership on the Business Performance through Quality System for Manufacturing Companies in the North-east China, and research into the model of Quality Leadership is related with the Business Performance. A new questionnaire of QM based on Conti's Quality System thesis, was developed and tested. A statistical analysis of data was collected from Manufacturing Firms in the North-east China. As a result, Quality Leadership is the important drivers of Total Quality Management, and is related with the Quality System. Then, the Quality System is directly related with process, and process is also related with the Product Quality and the Business Performance. Of course, the Product Quality is directly related with the Business Performance in the end.

• 품질경영학회지
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• 제27권2호
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• pp.251-262
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• 1999

In the automated manufacturing systems, the problem regarding how to make production activities flexible is even more important and critical than that regarding how to product large quantities, and the more flexible, if possible, the manufacturing system is, the more competitiveness and profitable factors it gets. This research, therefore, concentrated on establishing the flexibility and evaluating performance on the manufacturing system, operational flexibility is considered because of enabling the manufacturing system to get both the improvement of production rate and the adaptive ability of environment changes. For it, we used the analytical tool, GSPNs, which is a kind of timed Petri-Nets. GSPNs is competent enough to consider practical situations just like operation priorities, machine failure, randomness, concurrency and so on. Through the GSPNs analysis, it is confirmed that in the manufacturing system with operational flexibility is compatible with the traditional performances such as production rate or mean waiting time.

• 한국표면공학회지
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• 제48권4호
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• pp.179-184
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• 2015

Quadrupole Mass Spectrometers (QMS) is a very useful tool in vacuum process diagnosis. Tungsten filament based ion sources are vulnerable to contamination from process gas monitoring. Common symptoms of quadrupole mass spectrometer malfunction is appearance of unwanted contaminant mass peaks or no detection of any ion peaks. We disassembled used quadrupole mass spectrometer and found out black insulating deposits on inside of ion source parts. Five steps of cleaning procedure were applied and almost full restoration of functions were confirmed in two types of closed ion source quadrupole mass spectrometer. By using a numerical modeling (CFD-ACE+) technique, the electric potential profile of ion source with/without insulating deposit was calculated and showed the possibility of quadrupole mass spectrometer malfunction by the deterioration of designed potential profile inside the ion source.