• Journal of the Korea Institute of Building Construction
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• v.11 no.1
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• pp.1-8
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• 2011

Linear scheduling method limits to present works of work breakdown structure as a form of lines and was often developed manually. In other words, linear schedule could not utilize activity, work breakdown structure, and etc. information of network schedule such as CPM(Critical Path Method) and has been used only for reporting or confirming construction master plan. Therefore, it is necessary to develop system which can automatically generating the linear schedule based on the network schedule having many accumulated and useful construction schedule information. Thus, this research has an effort to establish data process model, data flow diagram, and data model in order to make linear schedule. In addition, this research addresses the system solution structure, user interface class diagram and logic diagram, and data type schema. The results of this paper can be used as a preliminary research for developing linear schedule generating system prototype by utilizing the network schedule information.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.1
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• pp.33-45
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• 1995

This paper as a sequel to Kang et al. (1994) describes the development of a three-dimensional nonlinear Galerkin-FEM model. Nonlinear advective terms have been incorporated in a manner used by Lardner and Song (1992), that is, using velocities at given nodes computed with linear Galerkin FEM model. The Proposed model is computationally more efficient than previous nonlinear Galerkin models developed by Owen (1980) and Davies (1980) because the model uses a linear shape function as a basis and, furthermore, the similarity transform technique developed by Kang (1994). Two experiments have been carried out to examine effects of nonlinear terms. One is an experiment of wind-driven current in a rectangular basin (Heaps' basin) and the other is an experiment concerning eddy generation behind a jetty with specified downstream and upstream open boundary conditions. The computed Pattern was found to be in good agreement qualitatively with previous model experiments by Stelling (1984).

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.170-171
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• 2003

비선형 광학은 새로운 광원 개발, 광신호의 전광 고속 처리 같은 분야에 응용 가능하기 때문에 비선형 광학 특성이 좋은 물질의 개발과 정해진 특성을 극대화시킬 수 있는 여러 가지 위상정합 방법의 개발이 진행되고 있다. 우리는 특성이 클 뿐 아니라 만들기 쉽고 제조가격이 싸다는 장점을 갖는 유기 고분자에 대해 2차 비선형 광학 계수를 측정해 보았는데, 단순히 계수의 크기만을 측정하지 않고 계수의 부호도 직접 관찰하여 고분자를 이용한 준위상정합의 가능성을 확인하였다. (중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.432-438
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• 2017

The primary objective of the current work was to develop a standardized retrofit hull form capable of saving energy based on existing vessels. The bow shape of existing vessels was investigated, giving consideration to design draft and speed. Resistance performances were assessed for existing vessels according to operating conditions. Commercial CFD codes and model test materials were used for assessment of effective power. Three retrofit hull forms with minimum resistance were selected given real operating conditions. These vessels were named after customized ready-made hull forms to enable ship owners to make easier choices. The effective power of each vessel was estimated under real operating conditions. Subjects were operated with the lowest draft, and performance for retrofit No. 3 showed an 11-16% improvement in effective power at low speed ranges of 16-18 knots compared to existing vessels. When operated with a middle draft, performance for retrofit No. 3 showed a 6-11% improvement in effective power at low speed ranges compared to existing vessels. When operated with the highest draft, performance for all vessels showed little difference in effective power.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.6 s.40
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• pp.73-80
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• 2004

A nonlinear time-domain system identification algorithm using measured acceleration data is developed for structural damage assessment. To take account of nonlinear behavior of structural systems, an output error between measured and computed acceleration increments has been defined and a constrained nonlinear optimization problem is solved for optimal structural parameters. The algorithm estimates time-varying properties of stiffness and damping parameters. Nonlinear response of restoring force of a structural system is recovered by using the estimated time-varying structural properties and computed displacement by Newmark-$\beta$ method. In the recovery, no pre-defined model for inelastic behavior has been assumed. In developing the algorithm, noise and incomplete measurement in space and state have been considered. To examine the developed algorithm, numerical simulation and laboratory experimental studies on a three-story shear building have been carried out.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.4
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• pp.347-353
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• 2003

Lately, Digital Photogrammetry has been increasingly applied to various hightech industries and becomes one of more interesting focuses of study than ever. Thus, this study aims to develop a Road Horizontal Alignment Information System by means of digital photogrammetry. Data acquired from digital photographic techniques were processed using Delphi, an object oriented programming language to develop a computer aided program, that allows us to build the information on Road Horizontal Alignment(Beginning Point of Curve, Ending Point of Curve, Radius, Intersection Point). The developed program could maximize visualization for better analysis compared with traditional programs because it utilizes many image data. Comparing with data from traditional horizontal alignment extraction programs based on the principle of least square method, the data acquired by Horizontal Alignment Information and kinematic GPS showed out of the developed road information systems the improved accuracy of IP value up to about 2m in the direction of X, Y axes, where the accuracy of curve radius(R) becomes enhanced up to about 2.5 m.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.674-674
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• 2013

$600{\times}1200$ mm 기판에 대면적 CIGS 광흡수층 증착을 위한 선형증발원 개발을 위해 다른 크기의 노즐(nozzle)과 일정한 노즐 간격을 가지는 선형증발원의 플럭스 밀도(flux density)를 전산 모사하여 플럭스 균일도 ${\pm}5%$의 조건을 구하였다. 이를 바탕으로 제작된 선형증발원을 이용하여 Cu, In의 단일막 두께균일도를 확인하였고, CIGS 광흡수층을 동시증발법으로 증착하여 박막의 두께 균일도 및 증착 조성의 균일도로 선형 증발원을 평가하였다. EDS 조성 분석을 통해 구한 조성불균일도는 600 mm 폭에서 Cu $${\leq_-}6%$$, In $${\leq_-}3%$$ Ga $${\leq_-}1%$$ Se $${\leq_-}2%$$으로 균일한 조성비로 성막된 것을 확인하였고 SEM 분석을 통해 표면 결정립의 형상을 확인하였다. 또한 XRD측정을 통해 선형증발원 방향의 대면적 CIGS 광흡수층이 칼코피라이트(Chalcopyrite) 구조임을 확인하였다. 이를 통해서 개발된 선형증발원이 CIGS 광흡수층 증착에 적합함을 확인하였다.

• Korean Management Science Review
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• v.11 no.3
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• pp.27-34
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• 1994

본 연구에서는 우리나라의 경영과학 입문자들이 선형계획 모형 개발 및 해석을 용이하게 할 수 있도록, 사용하기 편리하고 안정된 선형계획법 소프트웨어를 만들었다. 이 소프트웨어는 풀 수 있는 문제의 크기는 50 * 50으로 제한한 반면 한글로 모두 처리되도록 하였으며, 풀다운 메뉴방식으로 user friendly하며, 입문자들이 쉽게 이해할 수 있는 LINDO식 입력방식을 취하였으며, 패키지 내부에 완벽한 Editing 기능을 갖고 있어서 모형의 수정 보완이 매우 편리하게 되어 있다. 본 논문에서는 이 소프트웨어의 특성과 구조를 살펴본다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.04a
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• pp.129-136
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• 1995

본 연구에서는 핵연료봉의 여러가지 모양형태에 대한 충격실험과 해석을 통해 비선형해석 code의 해석모델에 대한 검증을 수행하였다. 이 두 결과의 비교를 통해 개발된 모델은 다중 span을 갖는 보나 봉의 비선형충격해석에 충분히 사용될 수 있음을 확인하였다. 이러한 모델을 통한 비선형충격해석시 주의해야 할 점은 자유진동해석시의 고유진동수를 찾기 위한 경계조건을 정확히 하는 것이 중요하며, 또한 충격해석시의 정확한 충격등가스프링비를 결정하는 것이 중요하다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.03a
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• pp.131-134
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• 1998

컴퓨터 시뮬레이션을 수행하는 대부분의 시스팀들이 모든 현상을 선형(Linear System)으로 인지하고 그 특성을 분석하여 모형화(Modeling)하고 있으나 실제의 사물현상은 비선형(Non-Linear)적인 특성을 갖고 있다. 이 논문에서는 비선형적인 현상을 설명하기 위한 해결책으로 제시되고 있는 Chaos의 개요와 그 특성을 정리하고, 카오스의 여러 특성을 관찰하기 위하여 몇 개의 카오스현상을 통합한 시스템의 개발에 대하여 기술하였다.