지역 스키마 통합에 의한 효율적 데이터 웨어하우스 설계

이현창,김경창,지원철 한국전문가시스템학회 1997 학술대회 Vol.2 No.1

Enterprises, inspite of mainaining large volume of data, do not possess needed data but instead include unrelated, independent and individual data which are disparate data. Disparate data is ambiguous and it does not support current integrated information needed by the enterprise. In response to the above problems, data warehouse may provide a solution. Building a data warehouse needs a systematic design because of its complexity. The systematic design for end user requirement is very important in implementing an efficient data warehouse. This paper describes an efficient design methodology for data warehouse with case-based reasoning to cope with the requirements of end users.

효율적인 데이터 웨어하우스 설계를 위한 통합 방법론

金庚昶,李炫昌 弘益大學校 科學技術硏究所 1997 科學技術硏究論文集 Vol.8 No.-

Enterprises holding a lot of data do not prossess needed data but instead include unrelated, independant and individual data. As a result, it only contains disparate data. Disparate data is ambiguous and it does not support current integrated information. In response to the above problems, data warehouse may provide a solution. Building a data warehouse needs a systematic design because of its complexity. The systematic design for end user requirement is important in implementing an efficient data warehouse. This paper describes an efficient design methodology for data warehouse to cope with the requirements of end users.

건축기획업무의 체계화를 위한 기획모델 설정

이현창,장성준 대한건축학회 1998 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.18 No.2

대금산조 연구사의 분석적 검토와 문제점 고찰

이현창 민족음악학회 2004 음악과 민족 Vol.28 No.-

Critical review on previous research on Taeg m sanjo Lee, Hyun Chang The Instrument solo music, sanjo was influenced by pansori and sinawi has been communicated from the latter half of 19C. Sanjo is one of the most frequently played music and studied music. The number of the article on sanjo are about 300. The results of critical review on 28 Taeg m sanjo articles are classified four sort. Those are Research of the key and the melidy, Comparison of the melody among sects, Research of the grace note(sigimsae) and Analysis of rhythm. The problems of those research are as follows: 1. There are scarcely any critical review on previous research. 2. The method of research are attached and the contents are overlaped. 3. The view of research are fragmentary. the research was fragmentary toward systematic musicology than historical musicology. 4. The problem of notationing. the loss of the impromptu amusement was incurring when notation. Sanjo is not the past music. Because it started at the latter half of 19C and coming into existence a new school. And sanjo is loved very much nowadays. So I anticipate multiful research of sanjo and extension of it's functions.

대금산조 연구사의 분석적 검토와 문제점 고찰

이현창 민족음악학회 2004 음악과 민족 Vol.27 No.-

The instrument solo music, sanjo was influenced by pansori and sinawi has been communicated from the latter half of 1%. Sanjo is one of the most frequently played music and studied music. The number of the article on sanjo are about 300. The results of critical review on 28 Taeguˇm sanjo articles are classified four sort. Those are Research of the key and the melidy, Comparison of the melody among sects, Research of the grace note(sigimsae) and Analysis of rhythm. The problems of those research are as follows: 1. There are scarcely any critical review on previous research. 2. The method of research are attached and the contents are overlaped 3. The view of research are fragmentary. the research was fragmentary toward systematic musicology than historical musicology. 4. The problem of notationing. the loss of the impromptu amusement was incurring when notation. Sanjo is not the past music. Because it started at the latter half of 1% and coming into existence a new school. And sanjo is loved very much nowadays. So I anticipate multiful research of sanjo and extension of it s functions.

마이크로컨트롤러 포트의 3개 상태를 이용한 레졸버 기준신호의 생성 방법에 관한 연구

이현창 한국소프트웨어감정평가학회 2022 한국소프트웨어감정평가학회 논문지 Vol.18 No.2

In this paper, when generating a reference signal for a PMSM resolver, a hardware and software configuration method that can simplify the complexity of filter circuits and insensitive to changes in filter circuit characteristics is presented by composing triple signals using the port characteristics of the MCU. Accordingly, we analyzed the characteristics of the existing resolver reference signal and the filter circuit required for it, presented hardware that forms a three-level voltage output using the triple state characteristics of the MCU, and presented a software algorithm for constructing a sine wave using this. In order to prove the performance of the proposed method, the experimental circuit was constructed and the experiment was conducted. As a result, it was confirmed that the filter circuit was simplified to the 2nd order, but the circuit elements did not require high precision, although using the same number of MCU ports..

ER유체의 사용조건이 ER댐퍼의 댐핑력에 미치는 영향

이현창,이형식 三陟大學校 2004 論文集 Vol.37 No.-

The electro-rheological fluids for semi-active suspension system are a class of colloidal dispersion which e h b i t large reversible changes in their rheological behavior when they are subjected to external electrical fields. This paper presents Bingham properties of ER fluids subjected to temperature variations. In addition. an appropriate size of the ER damper for a passenger car is proposed to investigate the effects of Bingham characteristics on the damping performance. The filed-dependent damping forces are evaluated according to the temperature variation and sedimentation ratio.

마이크로컨트롤러 포트의 3개 상태를 이용한 DAC 해상도 향상에 관한 연구

이현창 한국소프트웨어감정평가학회 2023 한국소프트웨어감정평가학회 논문지 Vol.19 No.3

본 논문에서는 마이크로컨트롤러 포트의 3개 상태 특성을 이용해 최소의 포트 수로 디지털-아날로그 변환결과의 해상도를 향상시키는 방법을 제시하였다. 제시한 방법의 타당성 검증을 위해 현재 사용되고 있는 2개상태 디지털로 이루어진 디지털-아날로그 변환회로를 분석하고, 제시한 3개 상태 방법과 비교 분석하였다. 제시한 방법의 효과를 입증하기 위해 실험회로를 구성하고 실험을 진행하였으며, 그 결과 기존의 2개 상태방법에 비해 2-비트 사용 시 해상도가 4단계에서 9단계로 225%, 3-비트 사용 시 8단계에서 27단계로 338% 크게 증가함을 확인하였다. In this paper, a method for improving the resolution of digital-to-analog conversion with the minimum number of ports using the three-state characteristics of micro-controller ports is presented. To verify the validity of the proposed method, a digital-to-analog conversion circuit consisting of two-state digital that is currently being used was analyzed and compared with the proposed three-state method. In order to prove the effectiveness of the proposed method, an experimental circuit was constructed and an experiment was conducted. As a result of the experiment, it was confirmed that the resolution increased by 225% from step 4 to step 9 when using 2 bits compared to the existing two-state method, and increased by 338% from step 8 to step 27 when using 3 bits.

서평(書評) : 『조선시대 서울도시사』(고동환 지음)

이현창 경제사학회 2008 經濟史學 Vol.45 No.-

CNN 알고리즘을 이용한 의료 영상 데이터 크기에 따른 정확성 분석

이현창 한국엔터프라이즈아키텍처학회 2022 정보기술아키텍처연구 Vol.19 No.4

최근 인공지능에 대한 관심과 활용이 증가하면서 의료 산업의 패러다임도 치료나 병원중심의 이용에서 예방과 이용자 중심으로 변화되고 있다. 이와 관련된 기술발전은 의료 빅데이터 구축과 활용을 통한 서비스 향상 및 발전으로 이어지는 사례들로 많이 구축 활용되고 있다. 이에 본 연구에서는9천여 장의 의료 영상 데이터를 기반으로 입력 영상 크기 및 훈련 회수에 따라 정확성 값을 비교하여높은 결과 값을 갖는 입력 영상 데이터 조건을 찾는다. 이렇게 함으로써 소규모 의료 영상 데이터를이용하여 높은 정확성을 확보함으로써 적은 비용으로도 질병 유무 판단에 활용할 수 있을 것이다. 이를 위해 2차원 영상 데이터 학습과 정확성 분석에 효과적인 CNN 알고리즘을 사용하여 진행한다.