• 한국전기전자재료학회논문지
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• 제32권1호
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• pp.13-19
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• 2019

This paper proposes an easy algorithm for finding tapped-delay-line (TDL) filter coefficients in an adaptive filter algorithm using orthogonal input signals. The proposed algorithm can be used to obtain the coefficients and errors of a TDL filter without using an inverse orthogonalization process for the orthogonal input signals. The form of the proposed algorithm in this paper has the advantages of being easy to use and similar to the familiar recursive least-squares (RLS) algorithm. In order to evaluate the proposed algorithm, system identification simulation of the $11^{th}$-order finite-impulse-response (FIR) filter was performed. It is shown that the convergence characteristics of the learning curve and the tracking ability of the coefficient vectors are similar to those of the conventional RLS analysis. Also, the derived equations and computer simulation results ensure that the proposed algorithm can be used in a similar manner to the Levinson-Durbin algorithm.

• Geomechanics and Engineering
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• 제35권5호
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• pp.525-538
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• 2023

The development of a city is closely linked to the construction and operation of its subway system. However, constructing a new subway tunnel under an existing station is an extremely complex task, and the deformation characteristics and mechanical behavior of the new subway tunnel during the excavation process can greatly impact the normal operation of the existing station. Although the previous studies about the case of underpass engineering have been carried out, there is limited research on the condition of a newly-built subway tunnel that closely undercrossing an existing station with zero distance between them. Therefore, this study analyzes the deformation law and mechanical behavior characteristics of the preliminary lining of the underpass tunnel during the excavation process based on the real engineering case of Chengdu Metro Line 8. This study also makes an in-depth comparison of the influence of different excavation methods on this issue. Finally, the accuracy of numerical simulation is verified by comparing it with on-site result. The results indicate that the maximum bending moment mainly occurs at the floor slab of the preliminary lining, while that of the ceiling is small. The stress state at the ceiling position is less affected by the construction process of the pilot tunnel. Compared to the all-in-one excavation method, although the process of partial excavation method is more complicated, the deformation of preliminary lining caused by it is basically less than the upper limit value of the standard, while that of the all-in-one excavation method is beyond standard requirements.

• 한국과학교육학회지
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• 제29권5호
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• pp.552-563
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• 2009

우리나라 최초의 과학영재학교인 한국과학영재학교의 과학교육을 위한 학습 지원 체제 및 학습 환경을 진단하고 그 유용성에 대한 학생들의 인식을 분석하였다. 이 조사를 위하여 자체 개발한 선다형 검사 문항을 사용하였으며 각 학년별로 학습 지원 체계의 효용성에 대한 인식의 차이를 조사하였다. 연구대상은 한국과학영재학교의 재학생 129명을 대상으로 설문 조사하였다. 연구결과로 첫째, 한국과학영재학교의 과학교육을 위한 학습 지원 체제는 대체로 유용한 것으로 나타났으며, 학생들은 교과수업, 인터넷활용, 실험 및 실습실, 독서실, 자연과학도서관, 연구회활동 및 동아리, AA(Academic Advisor)제도 , SAF(Science Academy Fair), 전자교재, 외부연사 초청특강의 순으로 유용성이 높다고 평가하였다. 둘째, 학생들이 추가로 희망하는 학습관련 지원으로는 교과교사의 학습방법 안내, 구두발표 능력 향상 프로그램, 온 오프라인 학습공동체 구축 등이 있었다. 이러한 결과는 과학영재의 잠재적 미성취 현상을 줄이고 학생들의 학교 부적응 상태를 호전시킬 수 있는 하나의 방안이 될 수 있을 것이다. 또한 학교 측면에서의 학습지원 체제를 개선하여 향후 고등학생 수준의 과학영재교육의 방향을 설정하는 데에 시사점을 제공 할 수 있을 것이다.

• 보건교육건강증진학회지
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• 제22권2호
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• pp.97-110
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• 2005

Objectives: Recent studies have shown that tailored messages for cancer screening to the beliefs and stage of cancer screening behavior of individual women increases the take-up probability. Many studies on cancer screening have used the Transtheoretical Model (TTM) to identify variables associated with cancer screening behavior. This study was carried out to identify the cognitive-behavioral factors associated with stomach cancer screening among women aged 40 years and over, and to develop and evaluate a tailored educational program for stomach cancer screening by stages of change. Methods: Building on the TTM constructs, we conducted a quasi-experimental study(N=283) to test the effectiveness of a tailored educational program for endoscopic stomach cancer screening. We carried out pre and post tests in the experimental group(N=162) and the control group(N=121), and the experimental group was subdivided into an on-line group(N=81) and an off-line group(N=81) by educational methodology using e-mail and the postal service. We used the chi-square test, trend test, and paired t-test to test the effectiveness of the program for stomach cancer using a tailored stage-matched messages. Results: To examine the effectiveness of the program for stomach cancer screening by the tailored stage-matched messages, the stage-matched materials were offered to the experimental group(N=162) four times for 4 weeks. The stage-matched materials consisted of the four types for stomach cancer. The tailored message was effective in changing the cognitive-behavioral factors, such as experience process, behavior process, con opinion for stomach cancer, self-efficacy, and the behavioral stages for stomach cancer screening. The stomach cancer screening adherence was higher for the stage-matched materials using postal mail than for those using e-mail. Conclusion: To improve the stomach cancer screening rate, the use of tailored messages for stomach cancer screening will be generated using an expert system. Therefore the implementation of tailored educational program will be supported a partnership between public and private health organizations and increasing awareness of the necessity of community-based interventions.

• 복식문화연구
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• 제22권4호
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• pp.619-631
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• 2014

This study proposes an educational direction to be followed by the clothing departments of Korea's specialized high schools in order to help achieve high levels of job placements and to strengthen their students' competitiveness. A comparison was made of the curricula in Korea's specialized high schools and in several fashion schools in other countries including the United States, Italy, France, Taiwan, and Japan. To this end, publicly available educational records were retrieved from domestic school documentation, vocational high school portals, and domestic/overseas school web sites, and were then reviewed. The archival data extracted from these sources shows that the curricula of the three chosen domestic schools uniformly focus on foundational courses such as general computer skills, general design, accounting principles, design principles, and drawing, as well as practical courses such as the design of western clothing, fashion design, fashion CAD, management of clothing material, design of Korean clothing, and knitting. Unlike these standardized courses, it was found that overseas fashion schools provide a more technically-advanced and design-focused education based on the interests of the individual student. Moreover, their education system nurtures the students' creativity through adequate field experience and history/language education. The findings of this study suggest that Korean specialized high schools should find a way to accommodate their students' interests and to provide them with personalized fashion education by adopting a more flexible curriculum. An educational line that considers the individual student's aptitudes and career path will help foster creativity and novel ideas, which, in turn, will contribute to the development of the fashion industry.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1592-1596
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• 2010

To verify the dominance of microorganisms in wastewater biological treatment, PCR-DGGE (denaturing gradient gel electrophoresis) was performed as a supplementary support method for screening of the dominant microorganisms from activated sludge. Results suggest that the dominant microorganisms in activated sludge are primarily responsible for strengthening its effectiveness as a biological treatment system, followed by the non-main dominant microorganisms, whereas the non-dominant microorganisms showed no effects. The degree of microbial abundance present on the profile of PCR-DGGE was in line with the treatment efficiency of augmented activated sludge with isolated cultures, suggesting that PCR-DGGE can be used as an effective supplementary method for verifying culturable dominant microorganisms in activated sludge of coking wastewater.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.768-776
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• 2021

LVDC 배전계통에서 DC전원의 공급을 위한 컨버터나 DC차단기의 보호동작은 AC 보호기기 보다 훨씬 빠르기 때문에, 기존의 T-C곡선의 반 한시특성에 의한 보호기기간의 보호협조 운용이 어려운 문제점을 가지고 있다. 따라서, 본 논문에서는 LVDC 배전계통에서 사고지점에 따라 다양하게 나타날 수 있는 사고전류의 경사각 개념에 대하여 정의하고, 이를 바탕으로 컨버터와 보호기기간의 협조동작을 신속 정확하게 수행하고, 정전구간의 범위를 최소화할 수 있는 LVDC 배전계통의 사고구간분리 보호협조 알고리즘을 제안한다. 즉, LVDC 배전계통에서의 사고전류가 선로정수에 의해 사고지점에 따라 비례적으로 변하는 경사각의 특성을 이용하여 메인 컨버터가 탈락되기 전에 사고구간을 선택적으로 분리하도록 한다. 또한, 본 논문에서는 배전계통 상용해석 프로그램인 PSCAD/EMTDC를 이용하여 배전용 변전소, LVDC용 컨버터 그리고 LVDC 배전선로로 구성된 1.5kV급 LVDC 배전계통 모델링을 수행한다. 이를 바탕으로 사고지점에 따른 경사각 특성 및 보호협조 운용알고리즘을 분석한 결과, 메인 컨버터가 탈락하기 전 사고구간만을 2ms 이내에 분리하고 건전구간의 수용가에 미치는 영향을 최소화 할 수 있어, 본 논문에서 제안한 사고구간분리 보호협조 운용 알고리즘이 유용함을 확인하였다.

• Structural Engineering and Mechanics
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• 제67권6호
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• pp.671-682
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• 2018

The effect of earthquake induced torsion, due to mass eccentricities, is investigated with the objective of providing practical design guidelines for minimizing the torsional response of building structures. Current code provisions recommend performing three dimensional static or dynamic analyses, which involve shifting the centers of the floor masses from their nominal positions to what is called an accidental eccentricity. This procedure however may significantly increase the design cost of multistory buildings, due to the numerous possible spatial combinations of mass eccentricities and it is doubtful whether such a cost would be justifiable. This paper addresses this issue on a theoretical basis and investigates the torsional response of asymmetric multistory buildings in relation to their behavior when all floor masses lie on the same vertical line. This approach provides an insight on the overall seismic response of buildings and reveals how the torsional response of a structure is influenced by an arbitrary spatial combination of mass eccentricities. It also provides practical guidelines of how a structural configuration may be designed to sustain minor torsion, which is the main objective of any practicing engineer. A parametric study is presented on 9-story common building types having a mixed-type lateral load resisting system (frames, walls, coupled wall bents) and representative heightwise variations of accidental eccentricities.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2000년도 추계공동학술대회논문집
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• pp.647-655
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• 2000

이 연구는 학교 교사가 직접 System을 운영할 수 있도록 함으로써 학교교육과 방과후 교육을 연계시키고 현장 교육 중심의 사이버교육이 되도록 함을 목적으로 했다. 현재 많은 가정에 고속의 전용선이 설치됨으로써 각 가정에서도 ON-Line 교육에 쉽게 접근할 수 있게 되었다. 가상학교, 가상수업에 관한 기존 연구들은 주로 시스템의 설계에 치중하여, 이러한 시스템을 도입하려는 일선 학교에 구체적인 도움을 주지 못하고 있다. 따라서 본 연구에서는 기존 연구들이 제시하는 가상수업의 구성요소 중 공통적인 것을 선택하고 학교 현장에서 수학 교육을 담당하고 있는 교사가 직접 이 사이트를 실험적으로 운영하게 함으로써 실제교육 현장에서 사용 할 수 있도록 하였다. 또한 수업과 관련된 주제로 토론을 하거나, 학습자료 파일을 업로드 및 다운로드 할 수 있게 하고, 다른 지역의 개인이나 학급과 편리하게 의사소통을 할 수 있게 하고 개인 상담을 할 수 있는 메일기능을 활용하여 교수-학습을 용이하도록 하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.77-79
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• 1996

This paper presents an integrated stability analysis by the direct energy function method based on Equivalent Mechanical Model(EMM) which reflects the system behavior related to both angle and voltage stabilities. Actually, angle and voltage stability are intimately related in power system, so complete decoupling of these stability analysis is not possible in general, particularly in stressed power systems. In this paper, it is shown that a identical energy function can be used for angle and voltage stability analysis. The proposed energy function reflects the line resistances and reactive powers under the constraints of the same R/X ratio. The energy margin between UEP and SEP presents a good collapse proximity index in both types of stability analysis.