• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.693-702
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• 2002

The aim of this study is to develop a 3-dimensional dynamic analysis model, capable of considering the interaction between vehicles and bridges more accurately. The dynamic analysis model is developed with the high-speed train (KTX) and a 2-span continuous prestressed concrete box girder bridge with a double track. The 20-car model is developed using the moving vehicle model for the regular trainset. Three-dimensional frame elements are used for the bridge model. Using the developed models, a dynamic behavior analysis program is coded. The analytical results are compared with the dynamic field test results and found to be valid to yield quite accurate dynamic responses. Based on the results of this study, the hybrid model, made up of the moving vehicle model for the heaviest power car and the moving force model for the other cars, is quite simple and effective without loosing the accuracy that much. Under the coincidence condition of two trains traveling with resonance velocity in the opposite directions, it is necessary to check not only the dynamic responses of the bridge with one-way traffic but those with two- way coincidence.

• Journal of the military operations research society of Korea
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• v.32 no.2
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• pp.21-39
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• 2006

This paper presents a mixed linear and integer goal programming (GP) model to aid in strategic planning and scheduling of guard soldiers. The proposed model is a general-purpose model, hence can be used to produce an optimal schedule with respect to any user-provided combination of guard post objectives and soldier preferences. We extensively test the usefulness of the model on a real-life dataset from a guard post in the ROK Army with using three objectives set by the guard post and three preferences provided by individual solders. Numerical results and analysis from these experiments show that the proposed guard scheduling model efficiently as well as effectively generates an optimal guard schedule and can also be used for an optimal revision of any existing schedule. In summary, these illustrate that the proposed model can be practically used for optimal planning and scheduling of guard soldiers in guard posts.

• Journal of Korea Society of Industrial Information Systems
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• v.24 no.6
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• pp.55-65
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• 2019

With the advent of the Fourth Industrial Revolution and changes in the educational environment, team-based assignments are increasing in university classes. Effective team formation in team-based class is an important issue that affects students' satisfaction and the effectiveness of education. However, previous studies mostly focused on post analysis on the results of team formation, which makes it difficult to use them in actual classes. In this paper, we present a mathematical model of how to create a balanced team that reflects students' abilities and other characteristics. Characteristic values for assignment may be scores, such as students' proficiency, binary values such as gender, and multi-values, such as grade or department. This problem is a type of equitable partitioning problem, which takes the form of 0-1 integer programming, and the objective function is linear or nonlinear, depending on how balance is achieved. The basic model or the extended model presented can be applied to the situation where teams are balanced in consideration of various factors in actual class.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.742-750
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• 2007

This paper presents a mathematical model for a double-fleet operation in Korean high speed rail (HSR). KORAIL has a plan to launch new HSR units in 2010, which are composed of 10 railcars. The double-fleet operation assigns a single-unit or two-unit fleet to a segment, accommodating demand fluctuation. The proposed model assumes stochastic demand and uses chance-constrained constraints to assure a preset service level. It can be used in the tactical planning stage of the rail management as it includes several real-world conditions, such as the capacities of the infra-structures and operational procedures. In the solution approach, the expected revenue in the objective function is linearized by using expected marginal revenue, and the chance-constrained constraints are linearized by assuming that demands are normally distributed. Subsequently, the model can be solved by a mixed-integer linear programming solver fur small size problems. The test results of the model applied to Friday morning train schedules for one month sample data from KTX operation in 2004 shows that the proposed model could be utilized to determine the effectiveness of double-fleet operation, which could significantly increase the expected profit and seat utilization rates when properly maneuvered.

• The Journal of the Korea Contents Association
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• v.21 no.10
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• pp.309-321
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• 2021

While total sales of broadcasting business have been increasing, terrestrial broadcasters' sales are stagnant and comprehensive programming program providers(PPs)' sales are increasing. The purpose of this study is to derive implications by analyzing the relative efficiency and super-efficiency of domestic broadcasters in such an asymmetric situation. In this study, we use input and output data of three central terrestrial broadcasters and four comprehensive programming PPs from 2012 to 2019. For the analysis, Additive DEA model and Additive super-efficiency DEA model are used with the assumption of VRS condition since the broadcasting industry is characterized by economies of scale. As a result, we find out that the input excess of tangible assets is the most decisive cause of inefficiency that reduces the efficiency of central terrestrial broadcasters. On the other hand, for the comprehensive programming PPs, the input excess of tangible assets and the output shortfall of total sales are important factors of inefficiency.

• The Journal of the Korea Contents Association
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• v.17 no.6
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• pp.250-260
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• 2017

This study analyzed the impacts of programming characteristics perceived by the consumers of entertainment programs on general programming channels on watching intention and the data of a survey with 360 adult viewers in the capital area. Research questions were verified as follows: First, as a result of multiple regression to analyze the impacts of the factors of programming characteristics perceived by the consumers on their watching intention, setting personal characteristics as a control variable, programming characteristics as an independent variable and watching intention as a dependent variable, the regression model was significant. Thus, the more positive the perceived factors of programming characteristics, the more significant their watching intention improved. Second, the factors of programming characteristics significantly affecting watching intention had greater positive(+) impacts in the following order: Adjacency > substantiality > weight of genre > social evidence > relative advantage > ease of access.

• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.117-133
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• 2002

열차운영계획은 수송수요 산정, 운행노선계획, 열차시간표 작성 기관차 및 인원의 할당 등 광범위한 내용을 포괄하고 있으나, 본 논문에서는 계획의 초기단계에서 결정 가능한 운행노선계획을 대상으로 범위를 설정하였다. 운영목표에 따른 전략은 사용자, 운영자, 사회전체의 입장에서 고려될 수 있는데, 이러한 전략에 의해 운행 될 수 있는 열차운행패턴을 운영비용의 최소화, 통행시간의 최소화. 운영자 수익의 최대화 모형으로 해결하고자 하였다. 2004년 이후에 운행이 예상되는 고속철도/기존철도는 운영계획의 변경이 예상되는 바, 상기의 목표에 따라 열차운영패턴을 작성하여 개발된 효과척도의 적용을 통해 정책적인 적용가능성을 평가하였으며 기존 계획된 철도청의 운영계획과도 아울러 비교, 최적대안을 선정하였다. 본 고에서는 수리계획모형인 비선형정수계획모형(MINLP)으로서 국내 철도망에 부합하는 운영계획을 작성하였으며, 이에 따른 열차-km는 수익최대화 모형, 인-km는 철도청의 열차운영계획이 가장 많은 것으로 나타났다. 인-hour는 수익 최대화 모형과 통행시간 최소화 모형이 가장 적은 것으로 나타났는데, 이는 장거리 노선의 편성이 증가된 것으로 사료된다. 이러한 결과를 산출함에 있어. 어려운 점은 각 구간의 기하급수적 증가, 결정변수의 초기값 선정 등이 있으나, 그동안 연구된 각종 경험적 기법의 적용과 실제 편성 가능한 변수의 적용을 통해 이를 해결하였다. 추후 설정된 모형의 비교에 적합한 효과척도의 개발과 전국적으로 사례구간의 확장 및 모형의 최적대안 선택 시 효과척도의 가중치에 대한 연구가 필요할 것으로 사료된다.

• Korean Journal of Comparative Education
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• v.28 no.4
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• pp.221-248
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• 2018

The purpose of this study was to analyze the performance of the Daegu Happiness Competency Education Program. It was confirmed that students, parents, teachers, and education professions are aware of the middle and higher level of education for happiness in Daegu in terms of the formation and operation of the curriculum. There is no significant difference between students and parents in terms of average value, and teachers' perception level is relatively high, which is understandable in that teachers are the subjects of the curriculum organization and operation. In addition, there was no statistically significant difference between the parents and the school level, but there were significant differences between students and teachers. In particular, students' and teachers' perceptions were lowered as the number of schools increased, unlike the predictions. They showed the lowest results in the special schools, autonomous schools and special schools. The reason for this is that Daegu Happiness Competency Education was implemented in 2014, and it was because there was little room to recognize and accept the new curriculum due to the burden of college entrance examination or employment. In the future, it will naturally improve as the education process is settled, but here we can find suggestions for the establishment of Daegu Happiness Competency Education.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.546-555
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• 2019

This study aims to suggest a development process for the interior design major course at K University's school of design to educate specialists who can answer the needs of the industrial field. The study procedure first analyzed the internal and external environment to establish queries and development direction. A job model for the interior design industry was constructed while course modules were deducted based on job characteristics and was used to form a curriculum based on a 4 year course. Required personnel includes 'Interior Design Business and Marketing Specialists', 'Interior Design Space Planning Specialists' and 'Interior Design Construction Management Specialists'. 40 modules were drawn following the detailed job model structure. 1st year students are to follow a common curriculum, 2nd years the major foundation, 3rd years major intensive, and the 4th years major application. The practical importance of the research is to suggest a development process of major modules based on the standard job model and the organization structure of the interior design industry.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.149-152
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• 2004

기업들의 고객중심 마케팅 기법중 하나인 고객관계관리(CRM ： Customer Relationship Management)가 인터넷의 발전으로 온라인화 되고 있으며 다양하게 발전되어 왔다. 가장 대두되고 있는 문제는 고객 분류를 객관적인 방법으로 어떻게 자동화할 수 있는가 이다. 본 논문은 최적화 모형을 이용하여 고객 분류를 더욱 세밀하게 할 수 있음을 제안하였고 고객 집단 편성 최적화를 반영함으로써 고객을 최적으로 분류할 수 있는 시스템을 설계 및 구축하였다.