• Journal of Electrical Engineering and Technology
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• 제9권4호
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• pp.1385-1393
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• 2014

Gas insulated switchgear (GIS) is widely used in the power systems, however, the contacts overheating of the inside circuit breaker or disconnector may be a potential cause of developing accidents. As the temperature of the contacts cannot be directly acquired due to existence of the metallic shield, an infrared sensor is adopted to directly measure the temperature of the shield and then the contacts temperature can be indirectly obtained by data fitting, based on which the on-line temperature monitoring technology specifically for GIS contacts based on infrared sensing is proposed in this paper. A real GIS test platform is constructed and experimental studies are carried out to account for the influential factors that affect the accuracy of the infrared temperature measurement. A heat transfer model of the GIS module is also developed, together with experimental studies, the nonlinear temperature relationship among the contacts, the metallic shield and the environment based on a neural network algorithm is established. Finally, an integrated on-line temperature monitoring system for the GIS contacts is developed for on-site applications.

• 정보보호학회논문지
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• 제27권3호
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• pp.617-636
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• 2017

많은 기업에서 핵심 정보자산의 보호를 위해 보안관리 체계 강화 목적으로 ISO27001, 또는 K-ISMS 등 표준 보안 관리 체계를 도입하여 일정부분 성과를 얻고 있으나 최근 IT 기술의 발전과 침해수법의 진화 등으로 위협요인이 기하급수적으로 증가하고 있어 기업은 보안관리 측면에서 보다 더 신속하고, 정확한 대응조치가 필요하게 되었다. 이를 위해 보안관리 프로세스의 효율화, 핵심적 보안영역을 집중관리 할 수 있는 보안지표의 설정, 침해위험 영역을 사전 인지할 수 있는 위험지수의 산출 등을 바탕으로 한 '기업형 상시 보안관리 체계'를 연구하고, 전문가 집단의 의견을 조사하여 AHP(Analytic Hierarchy Process)방법론으로 적절성을 분석하였다. 본 연구를 통해 기업의 보안담당자들은 보안 관리 체계의 운영에 있어서 선제대응, 신속조치 등의 효율성을 향상시킬 수 있다.

• 한국산학기술학회논문지
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• 제8권6호
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• pp.1604-1612
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• 2007

최근 10년간 기업은 ERP시스템을 적극적으로 도입하였다. 이에 대한 평가도 많았지만 종합적인 평가 결과만 있을 뿐 구체적인 성과 창출에 대해서는 연구가 많지 않았다. 특히 ERP시스템의 도입의 성과가 한 가지로 나타날 수 없을 뿐만 아니라 성과 창출 단계도 상이하다. 따라서 본 연구에서는 확산된 국내 ERP시스템 사용 기업을 대상으로 ERP시스템의 경영성과 창출시점이 언제 나타나는지를 연구함으로써 ERP도입 업체의 경영성과를 예측하고, 이를 통한 ERP운영 방법론을 수정할 수 있는 기회를 부여하고자한다. ERP성과를 측정하기 위한 지표는 균형성과표를 활용하였다. 또한 ERP시스템 활성화 요인과 경영성과의 상관관계를 확인하기 위하여 상관관계 분석을 실시하였고, 빈도분석을 통하여 ERP시스템 단계에 따른 경영성과 창출단계를 연구하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.176-180
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• 2001

There are several factors causing re-work in CMP process such as improper polish time calculation by operator, removal rate decline of the polisher, unstable in-suit pad conditioning, slurry supply module problem and wafer carrier rotation inconsistency. And conclusively those fundimental reason for the re-work rate increasement is mainly from the cycle time delay between wafer polish and post measurement. Therefore, Wafer thickness measurement in wet condition could be able to remove those improper process conditions which may happen during the process in comparison with the conventional dried wafer measurement system and it can be able to reduce the CMP process cycle time. CMP scrap reduction by overpolish, re-work rate reduction, thickness control efficiency also can be easily achieved. CMP Equipment manufacturer also trying to develop integrated system which has multi-head & platen, cleaner, pre & post thickness measure and even control the polish time from the calculated removal rate of each polishing head by software. CMP re-work problem such as over & under polish by target thickness may result in the cycle time delay. By reducing those inefficient factors during the process and establish of the automatic process control, CLC system need to be adopted to maximize the process performance. Wafer to Wafer Polish Time Feed Back Control by measuring the wafer right after the polish shorten the polish time calculation for the next wafer and it lead to the perfect Post CMP target thickness control capability. By Monitoring all of the processed the wafer, CMP process will also be stabilize itself.

• 전력전자학회논문지
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• 제13권1호
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• pp.46-54
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• 2008

본 논문에서는 연료전지나 배터리 및 슈퍼커패시터 등의 전기화학적 전력기기의 임피던스 모델링에 적합한 저가의 임피던스 분광 시스템을 설계하고 구현하였다. 제안된 시스템은 간단한 센서회로 및 상용 DAQ(Data Acquisition) Board와 강력한 HMI(Human-Machine Interface)를 지원하는 그래픽 언어인 LabVIEW 소프트웨어를 이용하여 구성되었고 고가의 EIS(Electrochemical Impedance Spectroscopy) 장비를 대체하여 널리 사용될 수 있을 것으로 기대된다. 또한, 제안된 시스템에서는 Lock-in Amplifier를 이용함으로써 노이즈(Noise)가 많은 환경에서도 측정 주파수 성분의 정확한 측정이 가능하게 하였다. 제안된 시스템을 이용하여 Ballard Nexa 1.2kW PEM 연료전지 스택의 주파수별 임피던스를 측정하였고, 이를 바탕으로 한 등가 임피던스 모델도 제안된다. 제시된 모델과 개발된 장비의 유용함은 리플전류에 의한 연료전지 스택의 교류 손실 측정을 통해 증명된다.

• 대한지역사회영양학회지
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• 제2권5호
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• pp.721-727
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• 1997

This study investigated whether dietary factors are more influential factor than other health behavior such as drinking, smoking and exercise on abnormal serum cholesterol level inspite of Korean dietary pattern differences compared to Europeans and Americans. A double case control study model has been used for the study design. One model consisted of high blood cholesterol cases and control. the other model consisted of low blood cholesterol cased and controls. 5.398 sedentary male workers who had taken medical examinations at a university hospital were used as the study subjects. Out of the study subjects, 36individuals with high blood cholesterol cases and 30 individuals with low blood cholesterol cases were selected. For the 66 individual control selection, the individual control selection, the individuals matching method was adopted. The food frequency method was used to collect the data for assessment of the dietary factors. A standardized questionnaire was used to investigate other health behavior. logistic regression analysis was employed to measure the relative importance between the factors considered. There were no statistically significant differences observed in nutrients consumption or other health behavior among the low, normal and high blood cholesterol groups, An overmatching effect had been suspected as the cause of those findings. However, the results of logistic regression analysis to identify the factors influencing high serum cholesterol showed that odd ratios of dietary factors such as tocopherol(3.0) and saturated fatty acid(1.6) were higher than I. I of smoking and 1.2 of drinking. Similar results were also observed incases of low serum cholesterol. The above findings imply that although the dietary pattern is quite different from that of Europeans and America, the dietary factor is still a significant factor for abnormal blood cholesterol in Koreans. Therefore, the dietary risk factor identified in high fat consumption populations are still relevant for the relatively healthy Korean as guideline for preventive health practices. (Korean J Community Nutrition 2(5) : 721∼727, 1997)

• Environmental Analysis Health and Toxicology
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• 제26권
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• pp.9.1-9.9
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• 2011

Objectives: In order to evaluate which temperature index is the best predictor for the health impact assessment of heat stress in Korea, several indexes were compared. Methods: We adopted temperature, perceived temperature (PT), and apparent temperature (AT), as a heat stress index, and changes in the risk of death for Seoul and Daegu were estimated with $^1{\circ}C$ increases in those temperature indexes using generalized additive model (GAM) adjusted for the non-temperature related factors: time trends, seasonality, and air pollution. The estimated excess mortality and Akaike's Information Criterion (AIC) due to the increased temperature indexes for the $75^{th}$ percentile in the summers from 2001 to 2008 were compared and analyzed to define the best predictor. Results: For Seoul, all-cause mortality presented the highest percent increase (2.99% [95% CI, 2.43 to 3.54%]) in maximum temperature while AIC showed the lowest value when the all-cause daily death counts were fitted with the maximum PT for the $75^{th}$ percentile of summer. For Daegu, all-cause mortality presented the greatest percent increase (3.52% [95% CI, 2.23 to 4.80%]) in minimum temperature and AIC showed the lowest value in maximum temperature. No lag effect was found in the association between temperature and mortality for Seoul, whereas for Daegu one-day lag effect was noted. Conclusions: There was no one temperature measure that was superior to the others in summer. To adopt an appropriate temperature index, regional meteorological characteristics and the disease status of population should be considered.

• 정보보호학회논문지
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• 제28권1호
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• pp.41-51
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• 2018

형태보존 암호는 평문의 형태를 그대로 보존하여 암호화를 수행한다. 따라서 암호화 전 후에 대한 데이터베이스의 구조 변경을 최소화 시킬 수 있다. 예를 들어 신용카드, 주민등록번호와 같은 데이터에 대한 암호화를 수행할 경우 형태보존 암호는 평문과 동일한 형태의 암호문을 출력하기 때문에 형태가 갖춰진 기존의 데이터베이스 구조를 그대로 유지할 수 있다. 현재 미국표준기술연구소(NIST)는 형태보존 암호의 표준으로써 FF1과 FF3를 권장하고 있다. 최근 국내의 경우 매우 효율적인 형태보존 암호 알고리즘인 FEA를 형태보존 암호의 표준으로 채택하였다. 본 논문에서는 대한민국 형태보존 암호의 표준 알고리즘인 FEA를 분석하고 다양한 환경에서 최적 구현하여 FEA의 성능을 측정한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.1027-1031
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• 2006

이동차량이나 선박 등 육, 해상에서 응급환자를 모니터링 할 때 이동이 가능한 혈액상태를 즉각 알 수 있는 이동이 가능한 소형 분석시스템이 요구되고 있다. 기존의 방식은 환자의 혈액을 채취하여 수 시간 경과 후 에야 그 결과를 알 수 있기에 촉각을 다투는 환자에게는 매우 위험한 상황까지 올 수가 있다. 본 연구에서는 수 시간 걸리는 분석시간을 $1\sim5$분 이내로 단축하여 빠른 응급조치를 할 수 있도록 하였으며 수집된 정보를 블루투스기반을 통하여 근거리의 PC로 모니터링이 가능하도록 구현하였다. 기존제품의 워밍업시간이 25분 정도 소요되는 것을 약 7분 정도로 개선되어 보다 빠른 초기측정이 가능하였으며 DUAL 히팅 방식을 채택하여 주변의 미세한 온도까지도 오차 없이 시스템이 가동될 수 있도록 하였으며, 수집된 정보를 자체시스템에서도 볼 수 있으며 근거리에 있는 PC와 무선통신이 가능하도록 하여 실시간 또는 필요시에 데이터를 전송하여 기존정보와 비교 분석하여 보다 빠른치료를 할 수 있도록 하여 병원의 환자 관리 전산화에 크게 기여 할 것으로 사료된다.

• 보건의료산업학회지
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• 제5권2호
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• pp.77-89
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• 2011

This study conducted a secondary analysis by using original data of performed by Korea Institute for Health and Social Affairs to know factors affecting determinants of health using Lalonde model for the adults aged over 19 years living in Korea. The survey was conducted in 2009 and it evaluated finally 5,867 cases by excluding cases with no answer or a wrong answer. This study model adopted two categories of instrument measure health were objective (Average remaining lifetime) and subjective(EQ-5D) health status. The health determinants included in this study could be divided in to four categories, which were human biology, environment, lifestyle, and health care organization. The results were as follows. In the factors affecting average remaining lifetime, human biology were sex, ages, BMI, showed statistically significant difference, environment category were merry status, education showed statistically significant difference, lifestyle category were exercise, drunks showed statistically significant difference and health care organization category were vaccination, health screening showed statistically significant difference. In the factors affecting EQ-5D, human biology category and health care organization category showed with same average remaining lifetime, environment category were merry status, education, income showed statistically significant difference and lifestyle category were exercise, drunks, stress showed statistically significant difference. The results demonstrated that the best powerful factor was life style category and environment category, the least factor was health care organization category. So lifestyle style and environment category should be considered for the future health plan, budget allocation and the priority in the health care.