• 한국국방경영분석학회지
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• 제29권2호
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• pp.61-80
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• 2003

A fire sequencing problem is considered. Fire sequencing problem is a kind of scheduling problem that seeks to minimize the overall time span under a result of weapon­target allocation problem. The assigned weapons should impact a target simultaneously and a weapon cannot transfer the firing against another target before all planned rounds are consumed. The computational complexity of the fire sequencing problem is strongly NP­complete even if the number of weapons is two, so it is difficult to get the optimal solution in a reasonable time by the mathematical programming approach. Therefore, a genetic algorithm is adopted as a solution method, in which the representation of the solution, crossover and mutation strategies are applied on a specific condition. Computational results using randomly generated data are presented. We compared the solutions given by CPLEX and the genetic algorithm. Above $7(weapon){\times}15(target)$ size problems, CPLEX could not solve the problem even if we take enough time to solve the problem since the required memory size increases dramatically as the number of nodes expands. On the other hand, genetic algorithm approach solves all experimental problems very quickly and gives good solution quality.

• 한국컴퓨터정보학회논문지
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• 제24권9호
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• pp.9-20
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• 2019

In this paper, we study the university timetabling problem, which consists of two subproblems, the university course timetabling problem and the examination timetabling problem. Given a set of classrooms, students, teachers, and lectures, the problem is to assign a number of courses (and examinations) to suitable timeslots and classrooms while satisfying the given set of constraints. We discuss the modeling and solution approaches to construct course and examination timetables for one of the largest Korean university. By using binary integer programming formulations, we describe these two complex real-world problems. Then, we propose a solution method, called NOGOOD, to solve the examination timetabling model. The computation results show that NOGOOD finds the optimal examination schedule for the given instance. Although we consider a specific instance of the university timetabling problem, the methods we use can be applicable to modeling and solving other timetabling problems.

• Educational Technology International
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• 제14권2호
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• pp.137-166
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• 2013

Problem-based learning (PBL) in engineering education has been implemented in various ways. The wide range of PBL methods sometimes creates difficulties in implementing PBL. The purpose of this study was to identify the major variables that a teacher considers in PBL designs for an engineering course and suggest specific PBL methods according to the PBL design variables. This study was conducted using a review research method involving 21 studies from a range of engineering education fields. The results showed that the major variables that engineering professors need to consider when applying PBL are the authenticity of the PBL problem and the method of providing knowledge or information that the learners must know to solve the given problem. Based on the two variables identified, the following four types of PBL methods for engineering education are suggested: 1) lecture-based problem, 2) guided problem-based learning, 3) problem-based learning and 4) co-op problem-based learning.

• 한국콘텐츠학회논문지
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• 제13권11호
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• pp.1046-1057
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• 2013

본 연구의 목적은 일개 대학 간호과 3학년 학생 145명을 대상으로 학습유형별 시뮬레이션 교육 전 후 자기효능감, 문제해결능력, 임상수행능력 차이를 파악하여 학습유형별 시뮬레이션 교육을 제공하기 위한 기초자료를 마련하고자 실시하였다. 본 연구는 시뮬레이션교육 후 학습유형별로 효과를 검증하기 위한 단일군 전후설계 실험연구이다. 본 연구 결과 간호학생의 학습유형은 적응자가 가장 많았으며, 시뮬레이션 교육 후 문제해결능력(F=5.015, p=.02)과 임상수행능력(F=3.288, p=.02)은 유의한 차이를 나타냈으며, 문제해결능력은 융합자와 분사자가 적응자보다, 임상수행능력은 융합자가 적응자보다 유의하게 높게 나타나 학습유형별 시뮬레이션 교육의 효과에 차이가 있음을 확인하였다. 그러나 자기효능감은 통계적으로 유의한 차이를 나타나지 않았다. 이상의 연구결과를 바탕으로 학습유형별로 시뮬레이션교육을 제공할 수 있을 것으로 기대된다.

• 한국초등과학교육학회지:초등과학교육
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• 제17권1호
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• pp.75-87
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• 1998

The problem solving processes of elementary school children who are talented in science have been seldom studied. Researchers often resort to thinking aloud method to collect data of problem solving processes. The major purpose of the study is investigating high ability elementary school students' problem solving processes through the analysis of written responses to science problems in everyday context. 67 elementary students were participated Chungcheongbuk-do Elementary Science Contest held on October, 1997. The written responses of the contest participants to science problems in everyday context were analyzed in terms of problem solving processes. The findings of the research are as follows. (1) High ability elementary students use various concepts about air and water in the process of problem solving. (2) High ability elementary students use content specific problem solving strategies. (3) The problem solving processes of the high ability elementary students consist of problem representation, problem solution, and answer stages. Problem representation stage is further divided into translation and integration phases. Problem solving stage is composed of deciding relevant knowledge, strategy, and info..ins phases. (4) High ability elementary students' problem solving processes could be categorized into 11 qualitatively different groups. (5) Students failures in problem solving are explained by many phases of problem solving processes. Deciding relevant knowledge and inferring phases play major roles in problem solving. (6) The analysis of students' written responses, although has some limitations, could provide plenty of information about high ability elementary students' problem solving precesses.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.281-283
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• 2006

In this paper, we consider the problem of batch processing of orders, where either a single order or a pair of orders which satisfies specific conditions may be grouped in the same batch. The objective of the problem is to minimize the number of batches formed to accommodate all orders. We prose an approach based on a Known algorithm proven to be optimal for special class of problems with tree structure and show the approach to have the worst case ratio of $2-{\frac{2}{n}}$

• 한국경영과학회지
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• 제18권2호
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• pp.147-156
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• 1993

Recently a new concept of shadow prices, called average shadow price, has been developed. This paper provides a dual problem and the corresponding duality theorems justifying this new shadow price. The general duality framework is used. As an important secondary result, a new reduced class of price function, the pp. h.-class, has been developed for the general duality theory. This should be distinguished from other known reductions achieved in some specific areas of mathematical programming, in that it sustains the strong duality property in all the mathematical programs. The new general dual problem suggested with this pp. h.-class provides, as an optimal solution, the average shadow prices.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.128-134
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• 2002

This paper is to investigate adoptability of the genetic algorithm to the railway traffic conflict resolution problem. We categorize the problem in two cases, one is the specific-boundary case and the other is not. GA is may be used in the first case, but not for second case. For a sample problem, an GA is designed, and the GA is being compared with Ho's.

• 한국지능시스템학회논문지
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• 제14권1호
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• pp.69-74
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• 2004

A sequencing problem is to find an ordered sequence of some entities which maximizes (or minimize) the domain specific objective function. As some typical examples of sequencing problems, there are traveling salesman problem, job shop scheduling, flow shop scheduling, and so on. This paper introduces a new type of sequencing problems, named a sequencing problem with fuzzy preference relation, where a fuzzy preference relation is provided for the evaluation of the quality of sequences. It presents how such a problem can be formulated in terms of objective function. It also proposes a genetic algorithm applicable to such a sequencing problem.

• 대한가정학회지
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• 제39권5호
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• pp.15-26
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• 2001

The purpose of this study is to examine specific consumer problems in internet commerce and analyze them in the age of information. The way of sorting consumer problems in internet commerce from this study. For this empirical analysis, the data was collected 319 consumers by internet on-line survey from Feb. 13 to Feb. 20, 2000. The methods for study was frequency, percentage, mean, correlation, multiple regression using SAS PC program. The major findings of this study were as follows: 1. The level of consumer problem experiences in internet commerce was examined. The problems of privacy was the most problem and the problem of price was the second. Then delivery, advertisement, information was next, and the problem of quality, and A/S, change, cancel was the next consumer problem. 2. Among factors influence on experience consumer problem in internet commerce, the amount of usable money, information search were significant.