• 대한조선학회지
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• 제10권1호
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• pp.27-32
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• 1973

This paper shows the method for obtaining the body flutter velocity and frequency for flight body which consists of low aspect ratio wing and body combination by assuming slender body of cylinderical shell structure. The stiffness matrix of the cylinderical shell is represented from Donnel eq. by the finite difference method, and also unsteady aerodynamic influence matrix is represented by the Doublet Lattice Method of Albano & Rodden. The flutter matrix can be obtained from those matrices.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2007년도 한국지능정보시스템학회
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• pp.309-320
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• 2007

The data imbalance problem which can be uncounted in data mining classification problems typically means that there are more or less instances in a class than those in other classes. It causes low prediction accuracy of the minority class because classifiers tend to assign instances to major classes and ignore the minor class to reduce overall misclassification rate. In order to solve the data imbalance problem, there has been proposed a number of techniques based on resampling with replacement, adjusting decision thresholds, and adjusting the cost of the different classes. In this paper, we study the feasibility of the combination usage of the techniques previously proposed to deal with the data imbalance problem, and suggest a combination method using genetic algorithm to find the optimal combination ratio of the techniques. To improve the prediction accuracy of a minority class, we determine the combination ratio based on the F-value of the minority class as the fitness function of genetic algorithm. To compare the performance with those of single techniques and the matrix-style combination of random percentage, we performed experiments using four public datasets which has been generally used to compare the performance of methods for the data imbalance problem. From the results of experiments, we can find the usefulness of the proposed method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.69-70
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• 2022

The domestic process planning generally relies on calculations based on the construction-standard-production-rate. This method requires trial and error practice during the construction phase to deduce the optimized equipment combination for time and cost. Trial and error during construction can lead to cost overruns and schedule delays. Accordingly, this paper suggests an advanced method for establishing a productivity database based on combinations of equipment and also considering site conditions in order to reduce the timely effort for deducing the optimized equipment combination. For this purpose DES (Discrete Event Simulation) model was developed based on the information provided in the construction-standard-production-rate.

• 대한기계학회논문집
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• 제16권11호
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• pp.2098-2110
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• 1992

본 연구에서는 중간평면의 비선형 신장을 고려한 원판의 강제진동을 해석하기 위해 Fig.1과 같은 경계조건 즉 꺽쇠로 고정된(clamped) 경우를 생각한다.이 경우 에 고유진동수 사이엔 .omega.$_{1}$＋2.omega.$_{2}$＝.omega.$_{3}$의 관계가 존재하는데 이 관계가 내부공진 조건이 됨이 입증된다. 원판에 작용하는 가진력으로는 조화가진을 가정하 고 가진진동수가 2.omega.$_{1}$＋.omega.$_{2}$에 가까운 경우 즉 조합공진(combination reso- nance)일 때를 고려한다.

• 한국자동차공학회논문집
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• 제25권2호
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• pp.242-249
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• 2017

In this study, the relationship between the shape of a passenger airbag and the possibility of injury is analyzed using the Taguchi method. The optimal shape combination is proposed for a design guideline that can reduce the possibility of injury to the dummy. The airbag FE model for analysis is obtained using a CAD system that can change the shape through several independent variables. The widths of the left / right, top / bottom, and back / forth direction of the airbag shape are set as the design factors, and the effect of the combination injury probability according to the shape is analyzed. The minimum geometric combinations are obtained using the orthogonal array method. The signal to noise ratio is calculated and the optimal shape combination is obtained through sensitivity analysis. The obtained optimal shape combination is compared with the possibility of injury of the initial airbag shape to confirm improved airbag performance.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.858-864
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• 2007

This study investigated the antibacterial activities of sophoraflavanone G from Sophora flavescens in combination with two antimicrobial agents against oral bacteria. The combined effect of sophoraflavanone G and the antimicrobial agents was evaluated using the checkerboard method to obtain a fractional inhibitory concentration(FIC) index. The sophoraflavanone G+ampicillin(AM) combination was found to have a synergistic effect against S. mutans, S. sanguinis, S. sobrinus, S. gordonii, A. actinomycetemcomitans, F nucleatum, P. intermedia, and P. gingivalis, whereas the sophoraflavanone G+gentamicin(GM) combination had a synergistic effect against S. sanguinis, S. criceti, S. anginosus, A. actinomycetemcomitans, F nucleatum, P. intermedia, and P. gingivalis. Neither combination exhibited any antagonistic interactions(FIC index>4). In particular, the MICs/MBCs for all the bacteria were reduced to one-half$\sim$one-sixteenth as a result of the drug combinations. A synergistic interaction was also confirmed by time-kill studies for nine bacteria where the checkerboard suggested synergy. Thus, a strong bactericidal effect was exerted through the drug combinations, plus in vitro data suggested that sophoraflavanone G combined with other antibiotics may be microbiologically beneficial rather than antagonistic.

• 대한토목학회논문집
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• 제29권5A호
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• pp.467-475
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• 2009

기존의 연구들은 댐퍼만에 의한 부가감쇠비의 Universal Curve만을 제공하였기 때문에 실무에서는 케이블의 구조감쇠 및 공기역학적감쇠와 같은 자체감쇠를 독립적으로 고려하곤 한다. 즉, 케이블에 발생하는 자체감쇠비와 댐퍼에 의해 부여되는 Universal Curve로부터 얻은 부가감쇠비를 산술적으로 합하여 케이블-댐퍼 시스템의 전체감쇠비를 결정해 왔다. 하지만 이러한 선형조합 접근법은 이론적인 근거가 미약하며 관련된 연구도 찾아볼 수 없는 실정이므로 이에 관한 유효성을 검증해 볼 필요가 있다. 이것을 위해 본 연구에서는 자체감쇠를 고려한 전체감쇠비 해석법을 개발하여 정해를 제시하고 이것을 기존의 선형조합 접근법에 의해 얻어진 전체감쇠비와 비교하여 선형조합 접근법의 유효성 여부를 검증하였다. 본 연구의 결과에 의하면, 강성은 작고 최적감쇠계수와 비슷한 감쇠계수를 갖는 댐퍼가 지점에서 가깝게 설치되어 있으며, 케이블의 진동이 저차 모드 위주로 발생하고 케이블의 자체감쇠가 크지 않은 일반적인 풍환경에서는 기존의 연구그룹에서 제시하는 연구결과나 선형조합 접근법을 적용하는 것에 무리가 따르지 않는다. 하지만 외부댐퍼나 예기치 못한 고차 진동모드의 발생, 강성이 큰 댐퍼가 사용되는 경우에는 본 연구를 적용하는 것이 바람직한 것으로 나타났다. 본 연구는 케이블의 자체감쇠를 고려한 전체감쇠비의 정해를 제시하고 이것을 토대로 선형조합 접근법에 대한 적용근거를 제시하였다는 점에서 의미를 찾을 수 있다. 차후 본 연구를 발전시켜 공기역학적감쇠에 대응하는 최적감쇠계수를 실시간으로 제시할 수 있게 된다면 MR(Magneto-rheological) 댐퍼와 같은 준능동 댐퍼의 케이블-댐퍼 시스템 제어의 중요한 알고리즘이 될 것으로 기대된다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제15권5호
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• pp.375-379
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• 2009

도메인은 단백질의 진화와 삼차구조 및 분자 기능의 기본 단위체이다. 단백질은 한 개 이상의 도메인들로 구정 되며, 단백질의 기능 또한 각 도메인이 가진 기능의 집합으로 구현된다. 단백질은 특정 기능을 담당하기 위해 진화되어 왔으므로, 도메인 또한 단백질 내에서 기능을 위한 특정 조합 패턴, 즉 보존도메인 조합을 가진다. 본 논문은 각 도메인 조합의 진화상 보존 정도를 측정할 수 있는 연관성 규칙 기반 계산 기법을 제안한다. 제안된 기법은 기존 기법에서 주로 고려되었던 도메인 조합의 빈도뿐 아니라, 조합 내 소속 도메인간의 상호 의존도를 측정하여 주어진 조합의 보존 정도를 산출한다. 이를 기반으로 S.cerevisiae의 단백질을 대상으로 보존 도메인 조합을 추출하였으며, Gene Ontology를 이용하여 그 생물학적 의미를 분석하였다. 그 결과 제안된 기법으로 추출된 보존 도메인 조합은 기존의 것에 비해 조합 내 기능의 유사도가 높았으며, 따라서 제안된 기법이 생물학적 기능의 협업 위해 보존된 도메인 조합의 추출에 우수하다 할 것이다. 또한 S.cerevisiae 단백질체에는 서로 의존도가 높고 자주 나타나는 보존 도메인 조합이 존재하며, 그러한 조합들은 molecular function의 협업과 관련 있음을 밝혀냈다.

• 한국의류학회지
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• 제26권5호
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• pp.715-726
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• 2002

The purpose of this study was to investigate the visual sensibility of color combination for clothing. The color combination for clothing were divided into three types according to the color coordination. In each type, the stimulus was applied three combination method according to the chromatic color/chromatic color, the chromatic color/achromatic color, the achromatic color/achromatic color. As a result, 42 color combination for clothing were obtained. The survey has been done for the 42 color combination for clothing with 27 semantic differential hi-polar scales. The major findings of this research were as follows. 1. To explain the hierarchy of visual sensibility, two sensibility groups were classified, the first group being cute and bold sensibility and the second group being comfortable and soft sensibility. 2. As result of the factor analysis, 4 factors(attractiveness, cuteness, boldness, softness) were found to be constructing factors for visual sensibility of color combination for clothing. 3. To explain the hierarchy of visual sensibility, two sensibility groups were classified, the first group being cute and bold sensibility and the second group being comfortable and sort sensibility.

• 한국의류학회지
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• 제37권2호
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• pp.213-223
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• 2013

This study presents the process of fashion item development with velvet through creative thinking methods. Creativity is one of the most important requirements for a successful job career and education enhancing creative thinking is needed in the area of fabrication, product design, and marketing strategy development. Velvet was selected as a research stimulus because it is a luxurious fabric with various differential properties such as a soft touch, unique luster, excellent drapability, and fine physical properties. The research methodology included creative thinking methods review, the selection of the tools, idea sourcing and listing, sequential idea evaluation and sample product making. After review of the various creative thinking methods, a combination method and forced connection method were employed as research tools to confirm the usefulness of creative thinking training because of their independence of use and application simplicity. A total of 12 university students participated as subjects in this research. After some training, each student derived ten ideas for velvet products that utilized a combination method and forced connection method. A total of 120 ideas were evaluated for novelty, technical possibility, practicality, and marketability; subsequently, 24 ideas were adopted and developed as sample products. The effectiveness of creativity education in fabrication and product design classes was verified through the whole process of product planning.