• 한국경영과학회지
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• 제34권3호
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• pp.71-84
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• 2009

This paper considers a remanufacturing and purchasing planning problem, in which either used products(or wastes) are remanufactured or remanufactured products(or final products) are purchased to satisfy dynamic demands of remanufactured products over a discrete and finite time horizon. Also, as remanufactured products are purchased more than or equal to a special quantity Q, a discount price policy is applied. The problem assumes that the related cost(remanufacturing and inventory holding costs of used products, and the purchasing and inventory holding costs of remanufactured products) functions are concave and backlogging is not allowed. The objective of this paper is to determine the optimal remanufacturing and purchasing policy that minimizes the total cost to satisfy dynamic demands of remanufactured products. This paper characterizes the properties of the optimal policy and then, based on these properties, presents a dynamic programming algorithm to find the optimal policy. Also, a network-based procedure is proposed for the case of a large quantity of low cost used products. A numerical example is then presented to demonstrate the procedure of the proposed algorithm.

• 한국경영과학회지
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• 제6권1호
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• pp.57-64
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• 1981

The continuous increase of crude oil consumption has struck great impact into the world economy, When we consider disadvantageous articles in contract for oil import, it would be desirable to import in batch the total quantity of crude oil contracted, but which is not available under the present situation which has many constraints This paper treats of the ways to deliver the crude oil in a given period so as to maximize the profit derived from the sales of oil products, To do this we should consider the prices of crude oil and oil products, inventory cost, transportation cost, oil refinement cost, and fluctuations of these parameters in a given period. The case of Korea Oil Corporation is treated in this paper to generalize the problem of crude oil transportation from Middle East and formulated in a mathematical programming. This programming is transformed into Dynamic Programming through specifing states, stages, payoffs, and recursive function. To clarify these procedure and methods, the case of Korea Oil Corporation is dealt with again and demonstrated in detail.

• 한국의학물리학회지:의학물리
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• 제28권3호
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• pp.122-128
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• 2017

Eclipse Scripting Application Programming Interface (ESAPI) was devised to enhance the efficiency in such treatment related workflows as contouring, treatment planning, plan quality measure, and data-mining by communicating with the treatment planning system (TPS). It is provided in the form of C# programming based toolbox, which could be modified to fit into the clinical applications. The Scripting program, however, does not offer all potential functionalities that the users intend to develop. The shortcomings can be overcome by combining the Scripting programming with user-executable program on Windows or Linux. The executed program has greater freedom in implementation, which could strengthen the ability and availability of the Scripting on the clinical applications. This work shows the use of the Scripting programming throughout the simple modification of the given toolbox. Besides, it presents the implementation of combining both Scripting and user-executed programming based on MATLAB, applied to automated dynamic MLC wedge and FIF treatment planning procedure for promoting the planning efficiency.

• 한국농공학회지
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• 제39권2호
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• pp.74-85
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• 1997

This study aims at the development of a mathematical approach for the optimal water allocation in the river basin where available water is not in sufficient. Its optimal allocation model is determined from the comparison and analysis of mathematical programming techniques such as transportation programming and dynamic programming models at its optimal allocation models. The water allocation system used in this study is designed to be the optimal water allocation which can satisfy the water deficit in each district through inter-basin water transfer between Kumho river basin which is a tributary catchment of Nakdong river basin, and the adjacent Hyungsan river basin, Milyang river basin and Nakdong upstream river basin. A general rule of water allocation is obtained for each district in the basins as the result of analysis of the optimal water allocation in the water allocation system. Also a comparison of the developed models proves that there is no big difference between the models Therefore transportation programming model indicates most adequate to the complex water allocation system in terms of its characteristics It can be seen, however, that dynamic programming model shows water allocation effect which produces greater net benefit more or less.

• 한국컴퓨터정보학회논문지
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• 제14권4호
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• pp.1-8
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• 2009

이 논문에서는 철근 절단 작업의 계획 문제를 동적 계획법으로 해결하여 근사 최적의 절단 계획을 생성하도록 하는 소프트웨어의 구현을 다룬다. 일반적으로 실제 절단 작업에 요구되는 제약사항을 반영하여 최적의 자재 절단문제의 해를 얻는 알고리듬의 설계가 필요하다. 하지만, 이것은 다중 규격의 1차원 자재 절단 문제를 풀어야 하는 것으로, 최적의 해를 얻는 선형계획법은 폭발적인 계산량과 기억용량의 한계로 적용하기 어렵다. 이러한 한계를 해결하기 위하여, 동적계획법에 근거하며 자재 절단 문제를 재구성하고, 휴리스틱을 적용하여 유한 범위의 조합 열에서도 근사 최적의 해를 찾을 수 있는 탐색 기법을 사용한 자재 절단 계획 알고리듬을 제시하였다. 그리고, 자동화된 철근 가공 산업용 소프트웨어는 작업 환경에 맞게 사용이 편리한 그래픽 화면과 사용자 인터페이스가 요구되는데, 공개 소프트웨어를 활용한 GUI 라이브러리 툴킷인 GTK+를 활용하여 이를 구현하였다. 개발된 소프트웨어는 철근 가공의 현장 지식을 바탕으로 휴리스틱 지식을 획득하여 동적계획법에 적용시킨 것으로, 지역 전통 산업과 첨단 IT 산업이 접목된 융합 IT를 시도한 사례 연구이다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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• pp.72-72
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• 1995

• 디지털융복합연구
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• 제7권3호
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• pp.113-122
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• 2009

The majority of programming education in the learning place attaches importance more to grammar, memorization of the imperative sentence and explanation of the program language itself than the specific way to use the target language. In addition, it is mainly used to teach theoretical knowledge based on the text. Consequently, current programming education has not interested learners in the programming learning and has not improved their ability in programming problems of the real world. We therefore developed a learning tool of C-language, which is based on the Console Wrapper. The purpose of proposing the learning tool was to make the programming education break from the typical theoretical learning and to let learners be interested in the programming education. By using the dynamic screen instead of the static console screen, the learners could enjoy learning the program. As a result of this study, we could know that the programming education using our learning tool is more effective than the typical C language programming education.

• 한국지리정보학회지
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• 제7권2호
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• pp.16-28
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• 2004

영상 모자이크 작업에서 두 영상 간의 경계선이 보이지 않는 최적의 seam-line을 구하기 위해 화소값 차이 변환과 동적계획법 이용 알고리즘을 제안하였다. 영상 간의 경계선은 두 영상의 화소값 차이가 적은 화소를 따라 형성되는 것이 시각적 부담이 적다. 이 화소들을 연결하는 것은 최적 경로를 찾는 알고리즘을 이용할 수 있다. 최적 경로 결정에 효과적인 동적계획법을 seam-line 결정에 직접 적용하변 화소값의 차이뿐만 아니라, seam-line의 길이에 따라 영향을 받는 거리영향문제가 발생한다. 이 논문에서는 적응적 변환함수를 사용하여 비용 변환을 수행하고, 변환된 비용공간 상에서 동적계획법을 적용하여 거리영향이 억제된 최적 seam-line을 구할 수 있는 알고리즘을 개발하였다. 또한 결정된 seam-line을 평가하기 위해 일정한 개수의 상위 화소값의 차이를 누적한 값(SFBPD)을 척도로 제시하였다. 제안한 seam-line 결정방법을 다양한 종류의 영상에 대해 적용 실험하였으며, 시각적 및 SBPD 값에 의한 수치적 결과를 제시하였다.

• 한국컴퓨터정보학회논문지
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• 제14권9호
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• pp.1-10
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• 2009

웹 서비스 조합 분야는 단일 서비스를 재사용하여 가치 있는 서비스를 생성하기 위해 등장했으며, 최근에는 차세대 웹 서비스인 시멘틱 웹을 구현하기 위해 IOPE를 기반으로 단순 검색 및 조합 대신에 규칙이나 AI를 통한 검색 및 조합 방법이 제안되고 있다. 또한 보다 효율적인 모듈화를 위해 기존의 객체지향 프로그래밍 방식보다는 관점지향 프로그래밍 방식이 도입되고 있다. 본 논문에서는 시멘틱 웹을 위해 관점지향 프로그래밍(Aspect-Oriented Programming, AOP) 및 리플렉션(Reflection)을 적용한 동적 웹 서비스 조합 및 실행 기법을 설계한다. 제안하는 기법은 웹 서비스의 메타 데이터를 동적으로 획득하기 위해 리플렉션 기법을 사용하고 아울러 동적으로 웹 서비스를 조합하기 위해 AOP 기반 접근방식을 통해 바이트 코드를 생성한다. 또한 리플렉션을 이용한 동적 프록시 객체를 통해 조합된 웹 서비스를 실행하는 방식을 제안한다. 제안하는 기법의 성능 평가를 위해 비즈니스 로직 계층과 사용자 뷰 계층 측면에서 조합된 웹 서비스를 검색하는 것에 대한 실험을 수행한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2617-2622
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• 2003

The pH neutralization process has long been taken as a representative benchmark problem of nonlinear chemical process control due to its nonlinearity and time-varying nature. For general nonlinear processes, it is difficult to control with a linear model-based control method so nonlinear controls must be considered. Among the numerous approaches suggested, the most rigorous approach is the dynamic optimization. However, as the size of the problem grows, the dynamic programming approach is suffered from the curse of dimensionality. In order to avoid this problem, the Neuro-Dynamic Programming (NDP) approach was proposed by Bertsekas and Tsitsiklis (1996). The NDP approach is to utilize all the data collected to generate an approximation of optimal cost-to-go function which was used to find the optimal input movement in real time control. The approximation could be any type of function such as polynomials, neural networks and etc. In this study, an algorithm using NDP approach was applied to a pH neutralization process to investigate the feasibility of the NDP algorithm and to deepen the understanding of the basic characteristics of this algorithm. As the global approximator, the neural network which requires training and k-nearest neighbor method which requires querying instead of training are investigated. The global approximator requires optimal control strategy. If the optimal control strategy is not available, suboptimal control strategy can be used even though the laborious Bellman iterations are necessary. For pH neutralization process it is rather easy to devise an optimal control strategy. Thus, we used an optimal control strategy and did not perform the Bellman iteration. Also, the effects of constraints on control moves are studied. From the simulations, the NDP method outperforms the conventional PID control.