• 한국경영과학회지
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• 제21권2호
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• pp.17-33
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• 1996

Automatic transfer defined as an integrated system with a number of workstations, interstation storage buffers, automatic device and a control system, play a major role in ass production systems. Due to high capital investment needed for an automatic transferline, greater care should be taken in its design so as to maximize the system performance. One may to control the system performance is to control buffer storage. To control the interstation work-in-process inventory, we propose dual limit switches which control the buffer storage with two parameters, R and r. Under the policy, proceding station is forced down when the inventory level in the buffer reaches R until the level falls to r. For the model developed, we analyze the system characteristics and find the optimal control parameters with a serach procedure.

• 한국경영과학회지
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• 제21권2호
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• pp.95-109
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• 1996

In automobile industry, the depot (distribution center) system is utilized to adjust the inventory and to supply the demands to the firm timely. In case of the small lot demands of short delivery cycle and the long distance from the parts manufacturing to the firm, the depot system is very important. In this paper, a model to minimize the sum of costs of holding, inventory and transportation, is proposed to determine the optimal quantities of production and transportation in JTT system. Finally, computational results that verify the effectiveness of the proposed model are demonstrated.

• 산업경영시스템학회지
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• 제35권4호
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• pp.126-132
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• 2012

This paper deals with a centralized warehouse problem with multi-item and capacity constraint. The objective of this paper is to decide the number and location of centralized warehouses and determineorder quantity (Q), reorder point (r) of each centralized warehouse to minimize holding, setup, penalty, and transportation costs. Each centralized warehouse uses continuous review inventory policy and its budget is limited. A SA (Simulated Annealing) approach is developed and its performance is tested by using some computational experiments.

• Management Science and Financial Engineering
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• 제21권1호
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• pp.19-24
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• 2015

As decision makers do not make optimal decisions in practice despite the existence of optimal solutions in many models, there has been a rising interest in behavioral operations management recently. In this study, we aim for a comparative study to analyze the inventory decisions in Korea, America, and China, by conducting the same newsvendor experiment in Korea and compare the results with those of previous studies. From the comparative analysis, some national characteristics in decision-making processes have been observed but there is lowly significant difference in order quantities among the three groups. Korean students show lower level of understanding in demand distributions and tendencies of anchoring on the mean demand and being risk-averse. The finding that individuals make their own decisions differently based on their different behaviors suggests that we need to consider individual approach in analyzing human decision-making processes rather than adapting aggregate approach.

• 제어로봇시스템학회논문지
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• 제22권12호
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• pp.1040-1045
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• 2016

An inventory control system was developed for multiproduct batch plants with an arbitrary number of batch processes and storage units. Customer orders are received by the plant at intervals and in quantities that are subject to random fluctuations. The objective of the plant operation is to minimize the total cost while maintaining inventory levels within the storage or warehouse capacity by adjusting the startup times, the quantities of raw material orders, and production batch sizes. An adaptive model-based control algorithm was developed that uses a periodic square wave model to represent the flows of material between the processes and the storage units. The effectiveness of this approach was demonstrated by performing simulations.

• 수산해양교육연구
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• 제22권2호
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• pp.205-217
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• 2010

This study attempted to investigate the influence of psychological separation and parental attachment of school resilience of middle school students. Although six hundred forty two middle school students participated in this study, final subjects of this study were 492(male, 243; female, 249) ones. Participants completed Psychological Separation Inventory, Parental Attachment Inventory and School Resilience Scale. Collected data were statistically analyzed using t-test, product moment correlation coefficient and multiple regression. The results of analyses revealed psychological separation statistically significantly predicted school resilience of middle school students and parental attachment statistically significantly predicted school resilience of middle school students. Based upon above results, it is concluded that psychological separation and parental attachment can be useful protective factors for school resilience. The implications of these results were discussed and future research questions were suggested with several comments on limitations of this study.

• 대한가정학회지
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• 제29권1호
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• pp.189-201
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• 1991

The purpose of this study was to validate the KMBI(Korean Maternal Behavior Inventory). Subjects were 1179 mothers of 4th-6th graders in the elementary schools from 5 small and medium cities and 5 urban cities in Korea. Pearson's γ, Cronbach's α, Cramer'sν, one-way ANOVA were conducted for the statistical analyses. The major findings were as follows. 1. The reliability coefficient of the scale (α) were ranged 0.62-0.79 and 0.70-0.82. 2. The discriminant coefficients(ν)of the item were ranged 0.40-0.83. 3. By the analysis of multitrait-multimethod matrix, convergent validity coefficients(γ) were ranged 0.28-0.66: and discriminant validity coefficients(γ) were ranged 0.28-0.66. 4. Significant sex differences were found in the scores of Affection, Overprotection, Achievement, and Achieve Involvement: significant SES differences were found in the scores of Reasoning Guidance, Affection, Overprotection, Achievement, & Active Involvement: and significant region differences were found in the scores of Authoritarian Control and Achievement.

• 농업생명과학연구
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• 제53권2호
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• pp.65-75
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• 2019

Stem and root of elm trees have used as traditional medical materials, but there is little information on the distribution and resources of habitats. Korean native growing Ulmus spp. (U. davidiana var. Japonica, U. parvifolia, U. davidiana, and U. macrocarpa) genetic resources studied through The National Forest Inventory of Korea data and field survey. The distributions of U. davidiana var. japonica according to elevation distributed evenly. Both U. parvifolia and U. davidiana were inhabited mostly at less than 200 m of altitude. Each Ulmaceae species widely were distributed nationwide, but a dominant species was different depending on locals. It observed that Ulmaceae inhabits mainly in steep slopes of 31-45 degrees. Most of the habitats regenerated by natural seeding and the most abundant species were a codominant tree. Distribution of trees in U davidiana var. japonica was 7 m-13 m, and in young U. parvifolia and U. macrocarpa, more than 25% of young trees less than 7 m observed. The distribution of the diameter of breast height of the U. davidiana var. japonica was 46.4% for 11-20 cm, 52.6% for 11-20 cm in U. parvifolia. The average T/R ratio was 0.83, and the mean weight ratio of root bark was 62%. As the results of this study, the domestic Ulmaceae biomassare very small. It is difficult to harvest in that the habitat on the slope. Thus, it is too hard to develop functional materials using biomass at present. Therefore, it is necessary to develop technology for the selection and propagation of elite trees of Ulmaceae.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.323-324
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• 2017

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2019년도 하계 학술발표초록집
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• pp.236-237
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• 2019