• Structural Engineering and Mechanics
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• 제20권3호
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• pp.363-380
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• 2005

The cable tension plays an important role in the construction, assessment and long-term health monitoring of cable structures. The cable vibration equation is nonlinear if cable sag and bending stiffness are included. The engineering implementation of a vibration-based cable tension evaluation is mostly carried out by the simple taut string theory. However, the simple theory may cause unacceptable errors in many applications since the cable sag and bending stiffness are ignored. From the practical point of view, it is necessary to have empirical formulas if they are simple and yet accurate. Based on the solutions by means of energy method and fitting the exact solutions of cable vibration equations where the cable sag and bending stiffness are respectively taken into account, the empirical formulas are proposed in the paper to estimate cable tension based on the cable fundamental frequency only. The applicability of the proposed formulas is verified by comparing the results with those reported in the literatures and with the experimental results carried out on the stay cables in the laboratory. The proposed formulas are straightforward and they are convenient for practical engineers to fast estimate the cable tension by the cable fundamental frequency.

• 한국산학기술학회논문지
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• 제6권1호
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• pp.37-47
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• 2005

본 논문은 외란 제거 제어기의 실제적인 설계와 구현방법을 제안한다. 2 DOF 구조에서는 외란 제거의 성능은 순 방향 루프 제어기의 고 이득 없이 개선될 수 있다. 그러나, 2 DOF의 설계 방법이 2 DOF 수학적인 이론에 근거하기 때문에 다양한 응용 분야의 사용이 쉽지 않았다. 외란 관측기(Disturbance Observer, DOB)는 간단하지만, 매우 효과적인 2 DOF 제어기이다. 이 논문에서 기본적인 DOB 특성부터 설계와 구현의 기술적인 방법까지 실제적인 문제를 다룬다. 또한 실질적인 방법에 의하여 모델링하는 방법과 그 예를 설명하였다. 제안한 방법은 두 가지의 선형 모터 시스템으로 유용함을 증명하였다.

• Communications for Statistical Applications and Methods
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• 제18권2호
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• pp.171-177
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• 2011

실생활에서 얻어지는 자료에서 근사함수를 구성하기 위하여 모델링을 하기 전에 측정된 원자료로부터 이상치를 제거하는 것이 필요하다. 기존의 이상치 진단의 방법들은 시각화나 최대 잔차들을 이용해왔다. 그러나 종종 다차원의 입력자료를 가지는 비선형함수에 대한 이상치 진단은 좋지 않은 결과를 얻었다. 다차원 입력자료를 갖는 비선형함수에 대한 전형적인서포트 벡터 회귀에 기초한 이상치 진단방법들은 좋은 수행능력을 얻어지지만, 계산비용이나 모수들의 보정 등의 실질적인 문제점들을 가지고 있다. 본 논문에서 계산비용을 감소하고 이상치의 문턱을 적절히 정의하는 서포트 벡터회귀를 이용한 이상치 진단의 실질적인방법을 제안한다. 제안한 방법을 실제자료들에 적용하여 타당성을 보일 것이다.

• 한국의류학회지
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• 제22권5호
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• pp.607-616
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• 1998

The purpose of this study was to develope a practical color range for the fashion industry in Korea. 3623 color sample used by 109 brands from'93 spring/summer to'96 spring/summer were collected. Also, the application frequency and consumer responses of each collected colorwere analyzed in this study. To clarify the characterstics of color range used in the fashion industry, density of color was etermined by color clustering based on A: and consumer responses. The resultsof this study were as follow; 1. The result analyzed based on the Munsell System revealed that the distributions of hue were concentrated in R, YR, Y, and PB. The chroma was concenturated mostly in the low range and the value, on the contrary, showed relatively even distribution. 2. 458 representative colors were selected by color clustering based on the toEless than 1. 0. In addition, the frequency of color applications and consumer responses were also considered when selecting the colors frequently used in the fashion industry and finals, 1163 colors wereobtained. The color range of the representative colors showed similar color characteristics with the 3623 colors supplied by the fashion industry. As a results, this approach was proven to appropriate to develope a color range for a practical use. 3. In conclusion, around 1200 colors were suggested to organize the color range to reflect the characteristics of the fashion industry with an acceptable color differance for color planning and management.

• 대한조선학회논문집
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• 제37권4호
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• pp.1-10
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• 2000

일반 상선의 비선형 조파문제를 해석하기 위해 상방향 패널법에 기반을 둔 패널법을 개발하였다. 먼저 현재의 비선형 방법의 검증을 위해 많은 실험값이 존재하는 Series 60 선형에 개발된 방법을 적용하였다. 실제적인 응용의 경우로 KRISO 3600TEU 컨테이너선과 KRISO 300K 유조선에 개발된 방법을 적용하였다. 특히 두 상선이 유기하는 파계의 비선형성에 중점을 두고 계산된 파계를 KRISO의 실험값과 비교, 검증하였다. 현재의 비선형 방법은 Dawson의 방법이나 Neumann-Kelvin해와 같은 선형 방법에 비해 월등히 그 결과가 좋음이 확인되었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권7호
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• pp.3733-3755
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• 2019

E-cash has its merits comparing with other payment modes. However, there are two problems, which are how to achieve practical/complete tracing and how to achieve it in compact E-cash. First, the bank and the TTP (i.e., trusted third party) have different duties and powers in the reality. Therefore, double-spending tracing is bank's task, while unconditional tracing is TTP's task. In addition, it is desirable to provide lost-coin tracing before they are spent by anyone else. Second, compact E-cash is an efficient scheme, but tracing the coins from double-spender without TTP results in poor efficiency. To solve the problems, we present a compact E-cash scheme. For this purpose, we design an embedded structure of knowledge proof based on a new pseudorandom function and improve the computation complexity from O(k) to O(1). Double-spending tracing needs leaking dishonest users' secret knowledge, but preserving the anonymity of honest users needs zero-knowledge property, and our special knowledge proof achieves it with complete proofs. Moreover, the design is also useful for other applications, where both keeping zero-knowledge and leaking information are necessary.

• 정보보호학회논문지
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• 제20권3호
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• pp.105-111
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• 2010

본 논문은 다자간 환경에서 프라이버시를 보호하는 효율적인 DBSCAN 군집화 기법을 제안한다. 기존 DBSCAN 군집화 기법에 가짜 데이터 삽입을 통한 프라이버시 보호 기법을 적용해 다자간 환경에서 프라이버시를 보호하는 기법으로 확장했다. 기존의 프라이버시를 보호하는 다자간 환경의 군집화 기법들은 비효율적이어서 실제 환경에 적용하기 힘들지만 제안한 기법은 이러한 문제를 해결한 매우 효율적인 기법이다. 본 기법은 다자간 환경뿐만 아니라 비 다자간 환경에도 적용 가능한 효율적인 기법이다.

• Advances in Computational Design
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• 제7권1호
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• pp.1-17
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• 2022

In this study, a new strategy is presented to transmit the fundamental elastic beam problem into the modern optimization platform and solve it by using artificial intelligence (AI) tools. As a practical example, deflection of Euler-Bernoulli beam is mathematically formulated by 2nd-order ordinary differential equations (ODEs) in accordance to the classical beam theory. This fundamental engineer problem is then transmitted from classic formulation to its artificial-intelligence presentation where the behavior of the beam is simulated by using neural networks (NNs). The supervised training strategy is employed in the developed NNs implemented in the heuristic optimization algorithms as the fitness function. Different evolutionary optimization tools such as genetic algorithm (GA) and particle swarm optimization (PSO) are used to solve this non-linear optimization problem. The step-by-step procedure of the proposed method is presented in the form of a practical flowchart. The results indicate that the proposed method of using AI toolsin solving beam ODEs can efficiently lead to accurate solutions with low computational costs, and should prove useful to solve more complex practical applications.

• 유통과학연구
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• 제22권8호
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• pp.77-86
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• 2024

Purpose: This study investigates the psychological mechanisms of comparison within the design context of retail stores, products, and advertising. The research aims to expand the understanding of comparison psychology, encompassing social, cognitive, perceptual, and self-comparisons and their application in design practices. Research Design, Data, and Methodology: The study employs a comprehensive review of psychological theories related to comparison psychology. They were selected through extensive research on literature pertaining to design psychology and consumer behavior. The research integrates insights from psychology, marketing, consumer behavior, and design theory, supported by various design examples of retail stores, products, and advertising, to demonstrate the practical applications. Results: The findings reveal that comparison psychology significantly impacts consumer preferences and user experiences. For instance, the assimilation effect and prospect theory highlight how comparisons shape value judgments and design perceptions. Practical examples are used to illustrate the profound influence of comparative judgments in design. Conclusion: The study advocates for a "psychologically-informed approach" to design, promoting designs that are not only aesthetically pleasing and functionally sound but also psychologically aligned. By bridging the gap between psychological theories and practical design implementations, the research provides valuable insights for designers, marketers, and psychologists, enhancing the psychological efficacy of design.

• 한국정보과학회논문지:소프트웨어및응용
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• 제32권4호
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• pp.327-334
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• 2005

최근에 정보통신기술(ICT)이 교육과정에서 다양한 내용을 지도하는데 중요한 도구로 등장하였다. 본 논문에서는 자기조절 학습전략 수준에 따른 ICT 활용수업 모형이 정보활용 실천력에 미치는 영향을 검증하였다. 실험집단을 3개로 구성하고 ICT 활용수업 모형인 문제해결학습, 토의학습, 정보탐색학습 수업을 적용하였다. 실험 도구로는 자기조절 학습전략과 정보활용 실천력 설문지를 사용하였으며, 자기조절 학습전략 설문지로 사전검사를 실시하고 정보활용 실천력 설문지로 사전 및 사후 검사를 실시하였다. 실험에서 자기조절 학습전략 수준이 높은 집단이 낮은 집단보다 정보활용 실천력이 높게 나타났으며, 이외에도 다른 훙미로운 결과들이 나타났다.