• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.869-872
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• 2005

This research studied robust design of column part for LCD transfer system. $1^{st}$ DOE(Design of Experiment)was conducted to find out main effect factors. 36 experiments were performed and their results were shows that the geometric parameters(Low-length, Side-length, Upper-thickness, Middle-thickness)are more important than other factors. The main effect plots shows that the maximum deflection of column is minimized with increasing Low-length, Side-length, under-thickness and Middle-thickness. $2^{nd}$ DOE was conducted to obtain RMS(Response Surface Method)equation 25 experiments were conducted. The CCD(Central Composite Design)technique with four factors were used. The coefficient of determination $(R^2)$ for the calculated RSM equation was 0.986. Optimum design was conducted using the RSM equation Multi-island genetic algorithm was used to optimum design. Optimum value for Low-length. Side-length, Upper-thickness and Middle-thickness were 299.8mm, 180.3mm, 21.7mm, 21.9mm respectively. An approximate value of 5.054mm in deflection was expected to be a maximum under the optimum conditions. Six sigma robust design was conducted to find out guideline for control range of design parameter. To acquire six sigma level reliability, the standard deviation of design parameter should be controlled within 2% of average design value.

• Mass Spectrometry Letters
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• 제4권3호
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• pp.47-50
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• 2013

An ultra-fast generic LC-MS/MS method was developed for high-throughput quantification of discovery pharmacokinetic (PK) samples and its reliability was verified. The method involves a simple protein precipitation for sample preparation and the analysis by ultra-fast generic LC-MS/MS with the ballistic gradient program and selected reaction monitoring (SRM) mode. Approximately 290 new chemical entities (NCEs) (over 10,000 samples) from 5 therapeutic programs were analyzed. The calibration curves showed good linearity in the concentration range of 1, 2 or 5 to 2000 ng/mL. No significant ion suppression was observed in the elution region of all the NCEs. When approximately 300 plasma samples were continuously analyzed, the peak area of internal standard was constant and reproducible. In the repeated analysis of samples, the plasma concentrations and the area under the curve (AUC) were consistent with the results from the first analysis. These results showed that the present ultra-fast generic LC-MS/MS method is reliable in terms of selectivity, sensitivity, and reproducibility and could be useful for high-throughput quantification and other bioanalysis in drug discovery.

• Journal of Nutrition and Health
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• 제46권5호
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• pp.470-481
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• 2013

This study provides standardized scientific criteria for education materials on nutrition and diet that could be used in schools, workplaces, and health and medical facilities. The study was conducted from April 2011 to October 2011. Literature reviews, institutional visits, and telephone interviews were conducted for the first draft of the accreditation criteria. Expert meeting and advisory councils were conducted in order to obtain feedback after development of the first draft of accreditation criteria. In order to verify the validity and reliability of the first draft on certification criteria, a survey was sent out to 143 professionals, including professors, researchers, health and medical experts, teachers, nutrition teachers, dietitians, and clinical nutritionists. After several modifications, the final accreditation criteria were established for 1) printed materials (authority, credibility, objectivity, organization, editing, real-life usability, activities and participation, and public interest), 2) web-sites (authority, credibility, objectivity, design, real-life usability, accessibility, currency, and public interest) and 3) materials with activities (credibility, organization, design, convenience of utilizing, safety, and public interest). Out of several criteria, contents (authority, credibility. and objectivity) and publicity (public interest) areas are mandatory requirements. For the accreditation, books for learning and materials with activities are required to meet more than six evaluation components, and the other materials are required to meet more than five evaluation components, including the required area. Accreditation criteria developed in this study could be used as a standard for development or selection of good education materials for nutrition and dietary life.

• 한국지반환경공학회 논문집
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• 제16권6호
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• pp.5-11
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• 2015

최근 구조물 기초 분야에 대한 한계상태설계법이 국제적인 기술표준으로 요구됨에 따라 연구기반이 미약한 얕은기초에 대한 하중저항계수설계법 개발의 필요성이 대두되었다. 본 연구에서는 얕은기초 설계 시 풍화토 지반에 위치한 얕은기초에 대한 하중저항계수설계법의 적용 방안에 대하여 연구를 수행하고 그에 따른 저항계수를 제안하였다. 얕은기초 국내 설계 및 시공자료를 수집하여 확률통계학적 기법에 의한 분석을 수행함으로써 풍화토지반 얕은기초의 불확실성과 저항편향계수를 정량적으로 분석하고, 신뢰성 해석 LEVEL II를 이용하여 목표신뢰도 지수를 평가하였으며, 산정된 신뢰도지수를 기존 문헌 값과 비교 분석하여 풍화토 지반 얕은기초에 대한 목표신뢰도 지수를 선정하였다. 국내 풍화토지반 얕은기초에 대한 하중계수를 적용하여 저항계수를 보정하였으며, AASHTO의 하중계수를 적용한 저항계수와 비교 분석하였다.

• 산업경영시스템학회지
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• 제38권4호
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• pp.1-10
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• 2015

ISO 9001, quality management system, is widely known as advancing internal efficiency and productivity in various industry. As a result, the number of companies that have adopted ISO 9001's certification have been increasing continuously year by year since ISO 9000' family standard was published in 1987s. This fact shows that a lot of businesses are trying to get the accreditation for improving the competitiveness of quality. The purpose of this study is to present that ISO 9001's certification motives affect to the requirement's implementation and show that the execution of requirements influences on management performance in the small manufacturer. In order to carry out this research, we obtained 96 survey sheets and inspected twenty assumptions based on the reliability, validity of the questionnaires. The results of regression analysis are summarized as follows; First, the factors of certification motive influence on the requirement's implementation except resources management. Second, the two elements of ISO 9001 requirement, resources management and product realization, have an important effect on the operational performance and financial performance considerably in the companies that choose the internal motive. Finally, the two requisites of ISO 9001 requirement, resources management and measurement, analysis and improvement, affect to the operational performance and financial performance significantly in the businesses that select the external motive. Based on the results, the companies that choose the internal motive have a good performance to execute the ISO 9001 requirements. Also, to implement the requirements of ISO 9001 is helpful for the companies to produce the operational and financial performance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.380-386
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• 2008

The development of a new railway vehicle is under progress through the Next Generation High-Speed Rail Development Project in Korea. Its aim is to develope fundamental technology of the vehicle that can run over 400km/h. The new distributed traction bogie system, 'HEMU'(High-speed Electric Multiple Unit), will be used and is different from that of previously developed high speed railway vehicles. Previous vehicles adopted push-pull type system, which means one traction-car drives rest all of the vehicle. Due to the difference, investigation on dynamic behavior and its safety evaluation are necessary, as a part of verification of the design specification. In the paper, current progresses of researches are presented. And the High-Speed Railway vehicle system is evaluated for a dynamic characteristic simulation. Proper dynamic models including air-suspension system, wheel-rail, bogie and car-body is developed according to the vehicle simulation scenario. The basic platform for the development of dynamic solver is prepared using nodal, modal coordinate system and wheel-rail contact module. Operating scenario is prepared using commercial dynamic analysis program and used for development of dynamic model, which contains many parts such as carbodies, bogies and suspension systems. Furthermore, international safety standard is applied for final verification of the system. Finally, the reliability of the dynamic model will be verified with test results in the further researches. This research will propose a better solution when test results shows a problem in the parts and elements. Finally, the vehicle that has excellent performance will be developed, promoting academic achievement and technical development.

• 한국컴퓨터정보학회논문지
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• 제7권3호
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• pp.60-67
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• 2002

정보화 시대의 역기능으로서 존재하는 정보시스템에 대한 보안 위협은 날로 증가하고 있으며 이에 대한 체계적인 보안관리가 중요시되고 있다. 보안관리에 있어서 가장 중요한 것은 위협의 근원을 파악하여 대책을 수립하기 위한 위험분석이다. 따라서 제안모델은 보안성향상을 위하여 보안정책수립을 조언하도록 하고 경제적인 보안대응책 수립을 위하여 위험산출단계에 대하여 신뢰성을 향상 시켰다. 특히 대응책 단계에서 자산에 대하여 보안등급을 부여하여 자산간의 상호의존도를 검사하게 하고, 제시된 대응책의 구현은 표준모델과 다르게 제안모델에서는 자산별 제약사항을 식별하도록 하여 불필요한 대응책을 구현하지 않도록 하여 경제적인 대응책의 구현이 이루어질 수 있도록 모델을 개선하였다.

• 한국방재학회 논문집
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• 제11권2호
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• pp.59-66
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• 2011

본 연구에서는 콘크리트 사장교를 대상으로 차량주행속도와 교면아스팔트의 포장 상태, 차량중량 등을 실험변수로 하여 차량이 교량을 주행할 때 교면(보도)진동이 보행자에게 미치는 진동사용성 평가 방법에 대해 연구하고 그 결과로부터 진동사용성 여부를 평가하였다. 특히, 실험변수 가운데 교면포장 상태를 BMS기준에 의해 A와 C등급으로 구분하였다. 여기에는 진동을 발생시키는 에너지원을 "환산중량"으로 정의하고 차량주행 속도와 차량중량의 자승근을 곱한 형태로 사용하였다. 환산중량 228.0~1161.9 km/h kN 범위 내의 동일한 실험 조건에서 얻어진 교면포장 상태 A등급의 경우에 대한 C등급 경우의 진동가속도 응답 비율은 1.23~1.43으로 분석되어 교면포장 상태가 진동가속도 응답을 결정짓는데 큰 영향을 미치고 있음을 확인 할 수 있었다. 연구대상 교량의 교면 진동가속도 응답을 추정할 수 있는 진동추정식을 신뢰도 50%, 90%, 95%로 구분하여 제시하였으며, 실험 교량에서 교면 포장 A등급과 C등급의 경우 각각 전체응답의 30%, 40%가 레벨 C(강하게 감지)범위, 70%, 60%가 레벨 D(명확하게 감지) 범위에 있는 것으로 나타났다.

• 디지털융복합연구
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• 제19권9호
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• pp.209-215
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• 2021

데이터 품질 관리는 최근 중요한 이슈로 자리잡았다. 데이터베이스의 메타데이터 표준화는 데이터 품질관리 방안 중 하나이다. 본 연구에서는 일관된 메타데이터 관리를 위하여 표준단어사전 관리를 지원하는 알고리즘을 제시한다. 해당 알고리즘은 웹 사전 크롤링을 통해 데이터베이스 메타데이터의 동의어 관리 자동화를 지원한다. 또한 웹 사전 크롤링 과정에서 생길 수 있는 동음이의어 판별 이슈를 해결하여 데이터의 정확도를 향상시킨다. 본 연구에서 제안하는 알고리즘은 기존의 수동적 관리에 비해 메타데이터 데이터 품질의 신뢰도를 높인다. 또한 이음동의어 데이터 등록 및 관리에 소비되는 시간을 단축시킬 수 있다. 새로운 데이터 표준화 부분 자동화 모델에 대한 추가 연구는 향후 데이터 표준화 프로세스에서 자동화 가능한 작업을 파악하여 진행되어야 한다.

• 전력전자학회논문지
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• 제26권5호
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• pp.325-333
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• 2021

A 3 kW grid-tied PV inverter with Gallium nitride high-electron mobility transistor (GaN HEMT) for domestic commercialization was developed using boost converter and full-bridge inverter with LCL filter topology. Recently, many GaN HEMTs are manufactured as surface mount packages because of their lower parasitic inductance characteristic than standard TO (transistor outline) packages. A surface mount packaged GaN HEMT releases heat through either top or bottom cooling method. IGOT60R070D1 is selected as a key power semiconductor because it has a top cooling method and fairly low thermal resistances from junction to ambient. Its characteristics allow the design of a 3 kW inverter without forced convection, thereby providing great advantages in terms of easy maintenance and high reliability. 1EDF5673K is selected as a gate driver because its driving current and negative voltage output characteristics are highly optimized for IGOT60R070D1. An LCL filter with passive damping resistor is applied to attenuate the switching frequency harmonics to the grid-tied operation. The designed LCL filter parameters are validated with PSIM simulation. A prototype of 3 kW PV inverter with GaN HEMT is constructed to verify the performance of the power conversion system. It achieved high power density of 614 W/L and peak power efficiency of 99% for the boost converter and inverter.