• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 추계학술대회 논문집
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• pp.45-49
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• 2001

The length and the breadth or a very large floating airport are determined by airplane types and airport facilities. However, the depth affect not only the structural strength but also the functional requirement such as a possibility of taking off and landing. The optimization problem for determining the depth is to select a design so that the cost is minimized. In this paper, a general arrangement and a method to decide the depth are proposed. Strength, functional requirement, and possibility of occurrence of deck wetness and slamming are considered in order to determine the depth of structure. Hydrodynamic forces of the diffraction and radiatin problems are predicted by applying the source-dipole distribution method, and the structural responses are obtained by the finite element method.

• 한국유체기계학회 논문집
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• 제1권1호
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• pp.17-23
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• 1998

The blade failures are identified as the leading cause of unplanned outages for steam turbine. Most investigations of the failures are limited to material tests, chemical analysis of deposits, and possibly examination of material specimens. But to correct a blading problem requires more than positive identification of the mechanisms involved. An analytic procedure capable of predicting stress and dynamic characteristics of turbine blades is presented to increase steam turbine availability by decreasing blade failures. Finite element method is used to model and predict natural frequencies, steady and dynamic stresses of turbine blades. The procedure is illustrated by the case study. This procedure is used to guide, and support the plant manager's decision to avoid a costly, unplanned outage

• 한국소음진동공학회논문집
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• 제19권5호
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• pp.523-529
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• 2009

Smart sensor is known as intelligent sensor, it is different with other conventional sensors in the case of intelligent system embedded on it. Smart sensor has many benefits e.g. low-cost in usage, self-decision and self-diagnosis abilities. This sensor consists of perception element(sensing element), signal processing and technology of communication. In this work, a bridge and structure of smart sensor has been investigated to be capable to condition monitoring routine. This investigation involves low power consumption, software programming, fast data acquisition ability, and authoritativeness warranty. Moreover, this work also develops smart sensor to be capable to perform high sampling rate, high resolution of ADC, high memory capacity, and good communication for data transfer. The result shows that the developed smart sensor is promising to be applied to various industrial fields.

• 소음진동
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• 제7권4호
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• pp.701-708
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• 1997

Up to now, numerical methods such as Finite Element Method(FEM) or Boundary Element Method(BEM) have been widely used to find the optimized resonator's position during designing a car intake system. However, these methods are not useful at the first stage of car design since it is not easy to change a numerical model consist of a large mesh size. A software has been developed to cover the defects using 4-pole parameter method. The software is running at Windows 95 environment for a user's convenience. To show its usefulness, it is applied to a real automobile intake system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1995년도 추계학술대회논문집
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• pp.30-36
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• 1995

Conventionally design for multi-stage cold forging depends on the designer's experience and decision-making. Due to such non-deterministic nature of the process sequence design, a flexible inference engine is needed for process design expert system. In this study, A* searching algorithm was introduced to arrive at the vetter process sequence design considering the number of forming stages and levels of effective strain, effective stress, and forming load during the porcess. In order to optimize the process sequence in producing the final part, cost function was defined and minimized using the proposed A* searching algorithm. For verification of the designed forming sequences, forming experiments and finite element analyses were carried out in the present investigation. The developed expert system using A* searching algorithm can produce a flexible design system based on changes in the number of forming stages and weights.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.428-433
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• 2000

A disassembility assessment has mostly depend on the subjective decision making from the qualitative element. The work of disassembly is already classified with given disassemble points from the symbolic chart method. It is not useful in the practical assessment because it is not specified. The new method of design for disassembility assessment(DFDA) is practical to introduce the fuzzy number as the conversion of quantitative element from qualitative. It is appled to compare the usefulness of air-cleaner in Korea-Japan passenger-vehicle.

• 융합신호처리학회논문지
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• 제3권1호
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• pp.67-73
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• 2002

본 논문은 2차 평활요소를 사용한 최적 연속계 유한정정 서보시스템의 새로운 설계법을 제시한다. 직렬 적분 보상기와 지역 귀환보상기를 상태귀환 루프에 도입하여 연속유한정정제어기를 만든다. 평활요소의 감쇄비와 고유 각주파 수의 결정법을 서술한다. 입출력 특성이 어떻게 개선되는지를 수치예제를 통하여 보인다. 특히 임의의 시간에 인가되는 외란 및 가변 입력에 대한 CDBC를 설계하는 방법을 제시한다.

• 과학교육연구지
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• 제38권3호
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• pp.599-611
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• 2014

본 연구는 2009 개정 과학과 교육과정을 기반으로 개발된 고등학교 과학 교과서에서 창의 인성 교육을 실현하고, 교육과정의 목표를 달성할 수 있는 창의 인성 활동들이 얼마나 반영되었는지를 분석하고자 하였다. 창의 인성 활동 유형을 분석한 결과, 탐구의 비중이 가장 많았고, 읽기, 글쓰기, 토론 등 다양한 활동을 할 수 있게 구성된 것으로 나타났다. 또한, 창의 인성 활동을 창의적 사고와 인성 요소로 분석한 결과, 창의적 사고와 인성 요소의 구성은 다양하지 않았다. 창의적 사고는 주로 발산적 사고를 하고 수렴적 사고와 연관적 사고 순으로 나타났으며 인성 요소는 배려가 가장 많았고, 정직성, 협동성과 책임감 순으로 나타났다. 따라서 다양하고 수준 높은 창의 인성을 함양할 수 있는 다양한 활동 개발이 필요하다. 의사 결정 요소로 창의 인성활동을 분석한 결과, 가치 준거를 설정하는 활동과 결과를 검토하는 과정이 전혀 나타나지 않았으며, 전체적으로 의사 결정 요소가 거의 없는 것을 볼 수 있다. 따라서 합리적인 의사 결정 능력 함양을 위해서 구체적인 의사 결정 요소들이 제공되어야 한다.

• Journal of Preventive Medicine and Public Health
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• 제39권3호
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• pp.190-194
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• 2006

Epidemiology is the key element of public health and preventive medicine. Reversely, public health and social equity are the basic ground for epidemiologists. Current progress in the various fields of epidemiologic study in Korea calls for the increased participation of the trained epidemiologists. Expanding epidemiologic concepts to the wide spectrum of health and medical programs, active participation to the diversified health service fields and strengthening the role of epidemiology in the social and political decision making should be included in the perspectives of epidemiology in Korea. The future of epidemiology is certainly depend on the efforts of present epidemologists.

• 한국통신학회논문지
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• 제5권1호
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• pp.60-69
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• 1980

크고 複雜한 線形回路方程式을 갖는 큰 계통의 回路를 解析하기 위해서는 매우 많은 記憶容量과 時間이 必要하다. 이러한 記憶容量과 계산 時間을 줄이기 위해서 본 論文에서는 Sparse 行列을 利用하여 增幅回路의 最適 設計를 하였다.