• Proceedings of the Korea Society for Simulation Conference
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• 1994.10a
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• pp.1-2
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• 1994

With the prevalence of computers in modern organizations, simulation is receiving more atention as an effectvie decision -making tool. Simualtion is a computer-based numerical technique which uses mathmatical and logical models to approximate the behaviror of a real-world system. However, iptimization of synamic stochastic systems often defy analytical and algorithmic soluions. Although a simulation approach is often free fo the liminting assumption s of mathematical modeling, cost and time consiceration s make simulation the henayst's last resort. Therefore, whenever possible, analytical and algorithmica solutions are favored over simulation. This paper discussed the issues and procedrues for using simulation as a tool for optimization of stochastic complex systems that are dmodeled by computer simulation . Its emphasis is mostly on issues that are speicific to simulation optimization instead of consentrating on the general optimizationand mathematical programming techniques . A simulation optimization problem is an optimization problem where the objective function. constraints, or both are response that can only be evauated by computer simulation. As such, these functions are only implicit functions of decision parameters of the system, and often stochastic in nature as well. Most of optimization techniqes can be classified as single or multiple-resoneses techniques . The optimization of single response functins has been researched extensively and consists of many techniques. In the single response category, these strategies are gradient based search techniques, stochastic approximate techniques, response surface techniques, and heuristic search techniques. In the multiple response categroy, there are basically five distinct strategies for treating the responses and finding the optimum solution. These strategies are graphica techniqes, direct search techniques, constrained optimization techniques, unconstrained optimization techniques, and goal programming techniques. The choice of theprocedreu to employ in simulation optimization depends on the analyst and the problem to be solved. For many practival and industrial optimization problems where some or all of the system components are stochastic, the objective functions cannot be represented analytically. Therefore, modeling by computersimulation is one of the most effective means of studying such complex systems. In this paper, after discussion of simulation optmization techniques, the applications of above techniques will be presented in the modeling process of many flexible manufacturing systems.

• Journal of Fisheries and Marine Sciences Education
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• v.13 no.1
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• pp.99-116
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• 2001

Testing is a procedure used to measure a sample of behaviour in order to discover how well a seafarer performs, usually in comparison with others, or compared with identified performance criteria. In this context It is important that the test, in whatever form it is being used, yields consistent results by being valid, reliable and practical. Whilst we can only take a sample of a person's knowledge or comprehension about topic in this way, testing methods do provide a more reliable estimate of performance than most other observational techniques; unsystematic or irregular observation being too unreliable. The method of examination has been specified in the provisions of Regulation 12 of the Decree of the ship officers act as followings. Other necessary matters for conducting oral and written examinations have been set out by the Minister. But written examination is too shortage of period and small number of question to cover the qualification of each level and oral test is just simple and namely Traditionally, written examinations have been provided as the only means for determining the acquisition of knowledge by the mariner. Typically, the examination formats have taken the format of either an essay or multiple choice examinations. Essay items, used in the vast majority of subject examination(not in Korea), consisted of three basic types: situational, descriptive and computational. The level of certificate being examined determined the number and mix of the type of essay questions selected. Oral question has again been used by assessors of seafarer in a wide variety of contexts. Also, oral questioning is often used when observation of performance is undertaken to ask why a certain action has been taken, or to be broaden the scope of what has been observed. At end, Each techniques have their own advantage and disadvantage, so we have to choose some or all of the following techniques, depending upon the certificate, qualification or job for which the trainee is aiming. But in high lank, we have to use both of essay type and multiple choice and with enough time of oral test at least 30 minutes. Who would be the assessor? According to the STCW Code Section A-I/6, instructors, supervisor and assessors are appropriately qualified for particular types and levels of training or assessment of competence of seafarers either on board or ashore, as required under the Convention, in accordance with the provisions of this section.

• Journal of Korean Elementary Science Education
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• v.27 no.3
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• pp.273-286
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• 2008

The purpose of this study was to develop an instrument for assessing the attitude and the knowledge level of elementary school in-service and pre-service teachers' on the modem environmental issues, and to implement it. The results of this study could be summarized as following. First, the instrument for attitude was developed as a Likert-type scale, it was constituted of 30 items through the item-chosen processes to improve the validity and reliability. The Cronbach's Alpha coefficient of the attitude instrument was .899. Second, The instrument for knowledge was developed as a multiple-choice form with 와 distracts, and the final version was constituted of 35 items. The average discrimination, difficulty, and Cronbach's Alpha coefficient of the items were .367, .629, .899, respectively. Third, in-service elementary teachers have been thinking about the modern environmental problems more seriously than pre-service teachers. However, in-service teachers 'knowledge level was lower than pre-service teachers'. Fourth, women have been thinking about the modern environmental problems more seriously than men. However, there was no difference significantly between men and women on knowledge level. Fifth, This process of developing the instrument could be provided as a model for future research which will try to develop instruments for assessing attitude or knowledge of any new areas with constructs.

• Journal of The Korean Association For Science Education
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• v.21 no.2
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• pp.289-298
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• 2001

The effect of the instructional approach that asked students to check their problem-solving processes through a paired think-aloud problem solving after presenting molecular-level pictures and a four stage-problem solving strategy was investigated. Four high school classes (N = 191) were randomly assigned to St group (using Strategy individually), SL group (Solver Listener), St-SL group (using Strategy-Solver Listener), and control group. Although the test scores of the St-SL group on strategy performing ability were significantly higher than those of the control group, there was not significant difference for the scores in the multiple-choice algorithmic problems. Regarding the subcategories of strategy performing ability test, students' ability of understanding given of problems and deriving the proper physical quantity was improved, but their ability of setting up subgoals and reviewing their solving process was very low. The preference to the strategy of the St-SL group was more positive than that of the St group.

• Korean Parent-Child Health Journal
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• v.5 no.1
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• pp.38-49
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• 2002

The purpose of this study was to investigate the needs of a mother when getting the information from the child care web sites. The subjects of this study were collected through on-line and off-line and constituted of 157 mothers who had neonates and infancy. All the mothers could use the internet. On-line subjects were 135 mothers who were the members of "Child Rearing" circle of internet portal site, Daum (www.daum.net) and off-line subjects were 22 mothers who visited the pediatric outpatient department. The instrument had 15 items about needs for information of the child care web sites. 12 items were multiple choice-questions and 3 items were open questions. In data analysis, SPSSWIN 10.0 program was utilized for descriptive statistics. The results were as follows. 1. The most useful web content that mothers represented was food and nutrition(24.4%) and the other rated as following order; growth and development(21.1%), supports among parents(16.8%). 2. The most great web problem that mothers represented was depth of content(43 people) and the other rated as following order; objectivity, specialty and reliability of content(29 people), no problems (23 people), too much advertisements(17 people), obligation on member(4 people). 3. Mothers represented the highest information needs about play and education(65 people) and the other rated as following order; nutrition(44 people), managements of common health problems(39 people), experiences of other parents(10 people), child caring methods (38 people), exchanges of things(7 people). 4. Mothers represented the highest consultation needs about common health problem (62 people) and the other rated as following order; growth and activity(60 people), play and education(30 people), nutrition(22 people), child caring methods(9 people).

• Journal of Korean language education
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• v.25 no.1
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• pp.169-201
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• 2014

The purpose of this research is to analyze the problems of the way of the 32th TOPIK(advanced)'s management for the disabled examinee and to prescribe the management of the TOPIK for them. Since the TOPIK started in 1997, the number of examinee who take it as a qualifying exam for the university entrance have gradually increased. The first disabled examinee who wants to use the result of the TOPIK for entrance into the post graduated university took the 32th TOPIK(advanced level). However, there was no examination regulations and detailed management method for the disabled. The biggest problem was the examinee could not have braille test and answer. The exam supervisor read all that is printed on the test sheet. It caused two big problems. 1) The essay question in writing test became an oral test. 2) The strategies of answering to multiple choice questions could not be used in vocabulary/grammar, writing, listening, and specially reading section. The first problem is occurred because writing and speaking have different cognitive process. The second one can be strongly related to the result in reading section. Above all, these disrupt accurate assessment of the examinee's writing and reading achievement. Therefore, this research insists the TOPIK needs to have the regulation and prescribe the management for the disabled. This research suggests 5 regulations for the blind examinee which covers the test time, supervisor, place and request of the examinee. These refer to the regulation for the disable in the other tests, such as the college scholarship ability test, TOEFL, TEPS, and a civil service exam.

• Journal of Sasang Constitutional Medicine
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• v.15 no.3
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• pp.100-117
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• 2003

Background In Sasang Constitutional Medicine (SCM), human beings are classified into four constitutions: Taeyangin, Taewnin, Soyangin, and Soeumin. SCM presents various lifestyles and treatments for each constitution. The problem of SCM is that its diagnosis is so subjective that the result of the diagnosis depends on the doctor. In order to solve this problem, multiple approaches have been objectively researched. To use a questionnaire is the most common method among the different approaches. Since there are a few problems in the Questionnaire for the Sasang Constitution Classification II (QSCC II), which in recent days has been used frequently, the necessity of a new questionnaire has arisen. Objective The purpose of this study is to develop a new questionnaire for the objectivity of the Sasang Constitution Classification by complementing the existing questionnaire. Methods In order to search for the existing questionnaire's problems, I first compare the ratio of the amount of questions regarding external appearance to that of questions of mental characteristics and physiologic & pathologic symptoms in QSCCII and QSCCII +. We created the new questionnaires by reinterpreting ${\ulcorner}Dongyi$ Soose $Bowon{\lrcorner}$ through SCM professors' and medical residents' discussion and by adding some items related to the diagnosis about the constitution from other SCM books and clinical experience. Results 1. The new questionnaire for the Sasang Constitution Classification is self-reported questionnaire based on a multiple choice system of 4 questions. 2. The new questionnaire for the Sasang Constitution Classification consists of 28 questions, which include 7 questions about external appearance, 4 questions about mental characteristics, and 17 questions about physiologic & pathologic symptoms. 3. The new questionnaire for the Sasang Constitution Classification consists of 24 questions of Taeyangin, 28 of Taeumin, 28 of Soyongin, 28 of Soeumin. 4. We will have to verify validity and reliability of new questionnaire for rhe Sasang Constitution Classification.

• Journal of Korean Society of Transportation
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• v.28 no.3
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• pp.75-84
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• 2010

South Korea is seeking for a solution to the problems of traffic congestion and environment: the increase of bicycle use. However many people feel that using a bicycle is inconvenient. Therefore, we developed bicycle level of service model from the user's perspective so that the existing bicycle roads can be evaluated and improved. The purpose of this paper is to develop a bicycle level of service (LOS) model by considering user's satisfaction and multiple factors that affect bicycle LOS. Bicycle LOS criteria is estimated by applying an ordered probit model, which is suitable for research relating to choice. In addition, we determine the bicycle LOS using three-level(A-C) LOS structure from the user position considering the satisfaction level that people can distinguish clearly. The results show that the bicycle LOS is largely determined by the bicycle road width. Other factors are involved as well, including bicycle road type, the number of access and egress point on the bicycle road corridor, pedestrian volume, and frequency of meetings.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.119-125
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• 2010

The most important part in the decision making is to decide the weight of attributes which indicate the relative importance of the properties to be estimated with different criteria respectively. In this study, the new MCDM method which consider typical preexisting methods all together is proposed. For doing those, Weighted Utopian Approach is newly suggested by combining typical 7 weighting methods and distance-based Utopian Approach which is one of the MCDM methods. The suggested method has the advantage of accomplishing representativeness and universality of the MCDM methods because it incorporates multiple weighting methods of diverse characteristics. It also yields not only the one final result but also the results calculated from each weighting method, broadening the options of the choice to the alternatives. The application of the new model to virtual engineering problems show that we can perform the decision making and the assessment of priority order more objectively with it and that it has high applicability to the practice, giving us simple calculation process.

• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.696-705
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• 2002

The main purpose of this study is to investigate whether the correlational reasoning activities could improve middle school students' correlational reasoning abilities. The subjects were 8th grade students, and the correlational reasoning activities of the CASE(cognitive acceleration through science education) program was intervened to the experimental group(n=111) during science class while usual science instruction was given to the control group(n=55). The correlational reasoning test was administered before and after the intervention. The pre-test results showed that most of subjects performed poorly in correlation problems and no significant differences were found between the two groups. In the post-test, the experimental group showed enhanced performance while the control group did not. Therefore it can be concluded that CASE program activities help the students to improve correlational reasoning ability. However, the proportions of students gave correct response were not so high: 27% for the multiple-choice item and about 6% for the essay-type items.