• 한국정보과학회논문지:데이타베이스
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• 제32권5호
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• pp.473-486
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• 2005

최근에 Agrawal 등이 제안한 히포크라테스 데이타베이스는 관계형 데이타베이스에 프라이버시 보호 기능을 추가한 데이타베이스 모델이다. 본 논문의 저자들은 히포크라테스 데이타베이스 모델을 XML 데이타베이스에 적용할 수 있도록 확장한 히포크라테스 XML 데이타베이스 모델[4]을 제안하였다. 본 논문에서는 동적 프레디킷(dynamic predicate)이라는 새로운 개념을 제안하고, 히포크라테스 XML 데이타베이스 모델에서의 액세스 통제에 이 개념을 적용한다. 동적 프레디킷은 권한에 의해 액세스가 허용되는지를 결정하는데 적용될 수 있는 질의 처리 도중에 동적으로 생성되는 조건을 나타낸다. 동적 프레디킷은 권한 검사를 질의 계획에 효과적으로 통합하여 액세스가 허용되지 않은 엘리먼트들이 질의 처리 과정에서 일찍 제외될 수 있게 해준다. 합성 데이타와 실제 데이타를 사용하여 기존의 액세스 통제 방법과 질의 처리 시간을 비교하는 다양한 실험을 수행한 결과, 본 논문에서 제안한 액세스 통제 방법은 하향식 액세스 통제 방법에 비하여 최대 219배, 상향식 액세스 통제 방법에 비하여 최대 499배 성능을 향상시킴을 보였다. 본 논문의 주요 공헌은 히포크라테스 XML 데이타베이스 모델 상에서 동적 프레디킷을 사용하여 액세스 통제 방법을 질의 계획에 효과적으로 통합할 수 있도록 한 것이다.

• 한국컴퓨터산업학회논문지
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• 제3권9호
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• pp.1207-1214
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• 2002

본 연구에서는 ICT(Information ＆ Communication Technology)활용 교수ㆍ학습 지도안을 Web상에서 작성 및 활용이 가능하도록 Web기반 전자지도안 시스템을 개발하여 첫째, 본 시스템만의 ICT 활용 교수ㆍ학습 과정안 형태를 구안하였으며 둘째, 한국형 교육과정과 ICT활용 교수ㆍ학습 과정안의 형태에 맞는 전자 지도안 시스템의 데이터베이스를 설계 및 구축하였으며, 셋째, 손쉽게 전자 지도안을 작성하고 지도안과 ICT 자료들이 효과적으로 연동하도록 시스템을 구현하였다. 마지막으로 구축한 전자 지도안 시스템을 실제 초등학교 현장에 적용하여 지도안 시스템의 효과와 개선점을 분석하였다. 본 전자 지도안 시스템은 수업 현장에서 가장 필요로 하는 ICT자료를 DB화하여 체계적인 지도안을 관리할 수 있다. 또한 지도안과 자료실을 유기적으로 연동시켜 정적인 DB가 동적인 컨텐츠 저장소로 활용할 수 있다. 이 시스템 구축으로 교수학습 지도안의 공유, 활용, 저장성의 극대화를 이룩하였으며 교육 현장에 일반화되어 학교 정보화에 이바지할 것이다.

• 경영정보학연구
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• 제14권2호
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• pp.47-63
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• 2012

데이터 웨어하우징(Data Warehousing, DW) 개념이 탄생한 1970년대는 미국 유통 대기업 월마트가 폭증한 데이터베이스를 좀 더 효율적으로 보고자 했던 시기와 맞닿아 있다. 그러나 지금까지 월마트의 데이터 관리에 관한 논의는 대부분 생산관리, 재고관리 등 운영 측면이 강조되어 왔고 데이터 자체에 대한 관심은 상대적으로 적었다고 할 수 있다. 본 연구는 데이터베이스에 관한 기술적인 개념을 먼저 아우른 뒤 월마트의 데이터 웨어하우징 프로젝트 사례를 구축 전(준비)-구축(실행)-구축 후(평가) 단계로 나누어 분석하였다. 본 연구는 월마트가 데이터 웨어하우징을 진행하면서 조직에서 지속적으로 발생하는 문제를 어떻게 해결하였는지, 그리고 데이터 관리를 통해 어떻게 전사적인 공헌을 이룩하였는지에 초점이 맞추어져 있다. 산업을 막론하고 전 세계적으로 가장 큰 데이터베이스를 가지고 있는 월마트의 사례를 현재의 관점에서 다시 살펴봄으로써 최근 재조명되고 있는 (빅)데이터 이슈와도 연결점을 찾을 수 있을 것이라 기대한다.

• 한국대기환경학회지
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• 제28권3호
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• pp.325-347
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• 2012

Long-term air and weather data monitored during the period of 2000 to 2009 were analyzed to quantitatively estimate the precipitation scavenging and wind dispersion contributions of ambient $PM_{10}$ and $NO_2$ in Korea. Both air pollutants and meteorological data had been respectively collected from 120 stations by the Ministry of Environment and from 20 weather stations by the Korea Meteorological Administrations in all parts of Korea. To stochastically identify the relation between a meteorological factor and an air pollutant, we initially defined the SR (scavenging ratio) and the DR (dispersion ratio) to separately calculate the precipitation and wind speed effects on the removal of a specific air pollutant. We could then estimate the OSC (overall scavenging contribution) and the ODC (overall dispersion contribution) with considering sectoral precipitation and wind speed probability density distributions independently. In this study, the SRs for both $PM_{10}$ and $NO_2$ were generally increased with increasing the amounts of precipitation and then the OSCs for $PM_{10}$ and $NO_2$ were estimated by 22.3% and 15.7% on an average in Korea, respectively. However, the trend of the DR was quite different from that of SR. The DR for $PM_{10}$ was increased with increasing wind speed up to 2.5 m/s and further the DR for $NO_2$ showed a minimum in the range of $1<WS{\leq}1.5$. The ODCs for $PM_{10}$ and $NO_2$ were estimated by 14.9% and 1.0% in Korea, respectively. Finally, we have also provided an interesting case study observed in Seoul.

• 한국대기환경학회지
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• 제29권3호
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• pp.297-306
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• 2013

This study used long-term air and weather data from 2000 to 2009 as raw data sets to develop regression models in order to estimate precipitation scavenging contributions of ambient $PM_{10}$ and $NO_2$ in Korea. The data were initially analyzed to calculate scavenging ratio (SR), defined as the removal efficiency for $PM_{10}$ and $NO_2$ by actual precipitation. Next, the effective scavenging contributions (ESC) with considering precipitation probability density were calculated for each sector of precipitation range. Finally, the empirical regression equations for the two air pollutants were separately developed, and then the equations were applied to test the model validity with the raw data sets of 2010 and 2011, which were not involved in the modeling process. The results showed that the predicted $PM_{10}$ ESC by the model was 23.8% and the observed $PM_{10}$ ESCs were 23.6% in 2010 and 24.0% in 2011, respectively. As for $NO_2$, the predicted ESC by the model was 16.3% and the observed ESCs were 16.4% in 2010 and 16.6% in 2011, respectively. Thus the developed regression models fitted quite well the actual scavenging contribution for both ambient $PM_{10}$ and $NO_2$. The models can then be used as a good tool to quantitatively apportion the natural and anthropogenic sink contribution in Korea. However, to apply the models for far future, the precipitation probability density function (PPDF) as a weather variable in the model equations must be renewed periodically to increase prediction accuracy and reliability. Further, in order to apply the models in a specific local area, it is recommended that the long-term oriented local PPDF should be inserted in the models.

• Structural Engineering and Mechanics
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• 제18권4호
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• pp.493-516
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• 2004

This paper addresses the behavior and strength of structural walls with a concrete compressive strength exceeding 69 MPa. This information also enhances the current database for improvement of design recommendations. The objectives of this investigation are to study the effect of axial-load ratio on seismic behavior of high-strength concrete flexural walls. An analysis has been carried out in order to assess the contribution of deformation components, i.e., flexural, diagonal shear, and sliding shear on total displacement. The results from the analysis are then utilized to evaluate the prevailing inelastic deformation mode in each of wall. Moment-curvature characteristics, ductility and damage index are quantified and discussed in relation with axial stress levels. Experimental results show that axial-load ratio have a significant effect on the flexural strength, failure mode, deformation characteristics and ductility of high-strength concrete structural walls.

• Journal of Information Processing Systems
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• 제14권2호
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• pp.435-447
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• 2018

Fingerprint-based biometric identification is one of the most interesting automatic systems for identifying individuals. Owing to the poor sensing environment and poor quality of skin, biometrics remains a challenging problem. The main contribution of this paper is to propose a new approach to recognizing a person's fingerprint using the fingerprint's local characteristics. The proposed approach introduces the barycenter notion applied to triangles formed by the Delaunay triangulation once the extraction of minutiae is achieved. This ensures the exact location of similar triangles generated by the Delaunay triangulation in the recognition process. The results of an experiment conducted on a challenging public database (i.e., FVC2004) show significant improvement with regard to fingerprint identification compared to simple Delaunay triangulation, and the obtained results are very encouraging.

• Toxicological Research
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• 제17권2호
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• pp.83-90
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• 2001

The background control data were compiled from rat developmental toxicity studies con-ducted at Toxicology Research Center, KRICT during the 1993-1999 period. These data were assembled in order to provide background in formation for the maternal and fetal data collected in 13 developmental toxicity studies using Sprague-Dawley rats. A total of 325 mated females were used in these studies during the seven-year period and overall pregnancy rate of these females was 93.8%. The present background control data included body weights, food consumption, hematological values, and organ weights of pregnant females, caesarean section data, and fetal examination data. These data can be used not only as a historical database for the meaningful interpretation of data from reproductive and developmental toxicity studies, but also as a contribution to biological characterization oj Sprague-Dawley rats.

• International Journal of Contents
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• 제13권2호
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• pp.14-20
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• 2017

The purpose of this study was to investigate the association of obesity with medical care use and costs according to overall diseases, cerebrovascular diseases (CVD), ischemic heart disease (IHD), hypertension (HTN) and diabetes mellitus (DM). The final sample was a group of persons who were free of diseases mentioned above and were not underweight. Their baseline screening program data and health insurance contribution data were connected with a 7-year medical claim database. The participants were classified according to their baseline BMI into normal, overweight, obese, and severely obese groups. Given the disease type, the total costs of DM showed the largest difference in each obesity group in both males and females. Also, the pharmacy costs for DM were more relevant than any other type of service to the obesity level. Considering the high prevalence of obesity and the relevantly increased medical care use and costs, there is a need for reduction in medical costs through obesity prevention efforts.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 B
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• pp.703-705
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• 1999

The Power supplies used commonly in the Nuclear, Thermal and Hydraulic Power Plant are required to test the function and reliabilities. For the better contribution of reliable operation and speedy maintenance of Power Plant, it is necessary to gather and analyze the datum, to print out the result of testing using PC and proper controllers. Various kinds of power supply shall be tested and examined automatically. By storing the test results in the Database it is possible to find out the changing of characteristics of power supplies. So it is very useful to prevent any problems that may occur in the power supplies.