• International Journal of Automotive Technology
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• 제8권3호
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• pp.351-359
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• 2007

In this study, a hierarchical switching control scheme based on robust control theory is proposed for tracking control of vehicle longitudinal acceleration in the presence of large uncertainties. A model set consisting of four multiplicative-uncertainty models is set up, and its corresponding controller set is designed by the LMI approach, which can ensures the robust performance of the closed loop system under arbitray switching. Based on the model set and the controller set, a switching index function by estimating the system gain of the uncertainties between the plant and the nominal model is designed to determine when and which controller should be switched into the closed loop. After theoretical analyses, experiments have also been carried out to validate the proposed control algorithm. The results show that the control system has good performance of robust stability and tracking ability in the presence of large uncertainties. The response time is smaller than 1.5s and the max tracking error is about $0.05\;m/S^2$ with the step input.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.59-64
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• 2001

The objectives of the thesis are to propose a pattern classification method for remote sensing data using artificial neural network. First, we apply the error back propagation algorithm to classify the remote sensing data. In this case, the classification performance depends on a training data set. Using the training data set and the error back propagation algorithm, a layered neural network is trained such that the training pattern are classified with a specified accuracy. After training the neural network, some pixels are deleted from the original training data set if they are incorrectly classified and a new training data set is built up. Once training is complete, a testing data set is classified by using the trained neural network. The classification results of Landsat TM data show that this approach produces excellent results which are more realistic and noiseless compared with a conventional Bayesian method.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 춘계학술대회 논문집
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• pp.401-405
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• 2004

Column subtraction, originally proposed by Harche and Thompson(]994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation. This paper aims at applying the column subtraction method to solve SSP which can not be solved by LP relaxation. For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch-and-bound algorithm by LINDO.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 춘계학술대회 논문집
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• pp.44-47
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• 2002

In order to make a doubly curved sheet metal effectively, a sheet metal forming process has been developed by adopting the flexibility of the incremental forming process and the principle of bending deformation which causes slight deformation to thickness. The developed process is an unconstrained forcing process with no holder. For this study, the experimental equipment is set up with the roll set which consists of two pairs of support rolls and one center roll. In the experiments using aluminum sheets and FEM simulation, it is found that the curvature of the formed sheet metal is determined by controlling the distance between supporting rolls in pairs and the forming depth of the center roll. The FEM simulation of the forming process using the roll set along the one path shows the distributions of the curvatures in two directions along the path, and gives information about the characteristics of the proposed forming process.

• 한국항해항만학회지
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• 제28권2호
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• pp.129-133
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• 2004

Column subtraction, originally proposed by Harche and Thompson(1994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation This paper aim, at applying the column subtraction method to solve SSP which am not be solved by LP relaxation For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch and-bound algorithm by LINDO.

• 한국정보처리학회논문지
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• 제6권10호
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• pp.2809-2815
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• 1999

Level set, and active contour(snakes) models are extensively used for image segmentation or shape extraction in computer vision. Snakes utilize the energy minimization concepts, and level set is based on the curve evolution in order to extract contours from image data. In general, these two models have their own drawbacks. For instance, snake acts pooly unless it is placed close to the wanted shape boundary, and it has difficult problem when image has multiple objects to be extracted. But, level set method is free of initial curve position problem, and has ability to handle topology of multiple objects. Nevertheless, level set method requires much more calculation time compared to snake model. In this paper, we use good points of two described models and also apply multi resolution algorithm in order to speed up the process without decreasing the performance of the shape extraction.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2006년도 추계학술발표대회 논문집
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• pp.159-162
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• 2006

The purpose of this study is to set up systematically housing adaptation items for the aged family. Housing adaptation items are classified by universal design principles. Also, this paper suggest to basic data for setting up various ranges according to each elderly people's conditions, adapting for elderly housing. Recently, in relation to the growing awareness of the ageing population, the necessity of policies for "aging in place" was emphasized by government. This paper is focused on the policy of elderly housings' adaptation for making housing for a lifetime. This new adaptation items for the elderly housing lead to the revitalization of policy ensuring housing in stock at the local authority level. In this paper, adaptation items were created after analyzing indices highlighted by previous studies related to evaluation items, design-guidelines for safety plans, designing elderly housing. The scope of adaptation items was limited to the indoor spaces of apartment due to the considerable increase of in-house accidents. To sum up, this study is aimed to set up adaptation items and then, to present the basic scheme for several users offering various ranges

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.209-211
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• 2007

2차원 상호작용하는 페르미온 계에 대한 혼돈 대각화 계산의 컴퓨터 계산 시간이, 대칭성 연산과 같은 여러 가지 방법을 이용함으로써 감소되었다. 첫째로, 각각의 격자를 업스핀(${\uparrow}$) 격자와 다운스핀(${\downarrow}$) 격자로 나누어서 2부분 격자가 가능케 했다. 이에 따라, 유효한 바탕 상태는 업스핀 배열에 다운스핀 배열을 겹침으로써 얻어진다. 결과적으로, 시험 바탕 상태를 저장하는데 사용되는 메모리 공간이 현저하게 감소되었다. 두 번째로, 바탕 상태 집합을 구성할 때, 해밀토니안 행렬의 원소들을 순람표에 기록하였다. 그럼으로써, 혼돈 대각화 과정에서 해밀토니안 행렬의 원소들을 반복적으로 계산하는 것을 피했다. 세 번째로, 바탕 상태 집합에 대칭성 연산을 적용함으로써 원 바탕 상태 집합이 대칭성 연산의 고유벡터들로 구성된 새로운 바탕 상태 집합으로 변환되었다. 기저 상태 파동함수는 대칭적인 바탕상태 (결합상태) 집합으로부터 구성되었다. 결과로서, 대칭성 연산을 이용함으로써, 혼돈 대각화 계산에 쓰이는 바탕상태의 총 개수가 50%까지 감소되었다.

• 한국산학기술학회논문지
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• 제15권5호
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• pp.3169-3175
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• 2014

본 연구에서는 상용 BIM툴에서 기본적으로 제공하는 물량산출 기능을 활용해 탄소배출량을 산정하는 BIM 라이브러리 구축과정을 정립하고 이를 철골조 건물에 적용함으로써 그 타당성을 검증하였다. BIM 라이브러리는 요구되는 부재별 탄소배출계수를 설정한 후 매개변수를 추출하고 Revit Architecture 2013을 활용해 프로젝트 단위 설정, 매개변수 설정, 탄소 배출량 산정식 설정의 절차를 거쳐 구축하였다. 이를 통해 철골부재의 단면종류별 탄소배출계수와 단면크기별 단위무게를 입력해주는 것만으로 별도의 수작업 없이 투입자재량에 따른 탄소배출량을 산정해 낼 수 있음을 확인하였다. 본 연구에서 제시한 BIM 라이브러리 구축과정을 통해 부재별 탄소배출량 산정 라이브러리를 구축함으로써 시공단계의 투입자재량에 따른 탄소배출량을 손쉽게 산정할 수 있으며, 프로젝트 초기 설계단계에서 탄소배출량을 최소화 할 수 있는 설계대안의 선택에 일조함으로써 친환경적 건설사업 수행 및 BIM의 실무적 활용성 향상에 도움을 줄 수 있을 것으로 기대된다.

• 대한수학회보
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• 제57권2호
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• pp.281-294
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• 2020

The initial-boundary value problem for a class of semilinear Klein-Gordon equation with logarithmic nonlinearity in bounded domain is studied. The existence of global solution for this problem is proved by using potential well method, and obtain the exponential decay of global solution through introducing an appropriate Lyapunov function. Meanwhile, the blow-up of solution in the unstable set is also obtained.