• Journal of Korean Institute of Industrial Engineers
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• v.38 no.2
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• pp.116-124
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• 2012

This paper concerns a joint replenishment problem for a single buyer who sells multiple types of items to end-customers. The buyer periodically replenishes the inventory of each item to a preset order-up-to-level to satisfy the end customers' demands, which may be non-stationary. A joint replenishment policy characterized by variable order-up-to-levels is proposed for the buyer who wishes to minimize the expected cost of operating the retail system. The proposed policy starts each period by calculating the expected cost of ordering and not ordering action based on the information of the current inventory position and forecasted demand for the upcoming period. It then takes advantage of an integer programming model to get a cost effective joint replenishment plan. Computer experiment was performed to test efficiency of the proposed policy. When compared with the most efficient policy currently available, our policy showed a considerable cost savings especially for the problems having non-stationary demands.

• Journal of Korean Institute of Industrial Engineers
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• v.13 no.2
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• pp.65-77
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• 1987

Congestion occurs whenever users interfere with each other, while competing for scarce resources. In a congested market, such as a telecommunication service market, users of telecommunication services incur costs in using the service in addition to the price. The user's own time costs involved in learning to use the service, waiting for the service, and making use of the service are typically greater than the price of telecommunication services. A market equilibrium analysis is performed in which a method for user demand aggregation is developed. The effects of price changes on user demands and market demands for congested services are examined. It is found that total market demands may increase as the price for less-congested services increase under certain demand conditions. This suggests that a nonuniform pricing scheme for a congested service may improve the utilization of the congested system. The sign of price cross-elasticity for congested services is show to vary with demand conditions. A possible complementary property of congested services is found and the implication of such a property is discussed. It is argued that such a complementary property may lead to a cross subsidy in a market with congestion. Finally, comparisons between uniform pricing and nonuniform pricing policies are made. A specific numerical example is given to show that a nonuniform pricing policy may be Pareto superior to a uniform pricing policy.

• Journal of Practical Engineering Education
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• v.9 no.1
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• pp.1-5
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• 2017

It is necessary to make efforts to resolve complaints such as the mismatch of the labor market and the re-education costs for the new employees by acting as the higher vocational education center of the university. This course introduces the case of developing a practical curriculum based on the competency units presented in the curriculum of the application system that meets the demands of the human resources development and the industrial field demands of the machinery area corresponding to the demand of the industrial society. By analyzing the job duties of industry, it is necessary to develop the new curriculum after grasping the level of demand according to the area, and the importance of the ability to equip as a professional technical manpower and to create high performance is increased. It will help to improve the employment rate of students through the development of field-oriented curriculum.

• Journal of the Korean Society of Clothing and Textiles
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• v.48 no.6
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• pp.1132-1147
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• 2024

This research aimed to identify key dynamic postures required by various industries for future population-based 3D anthropometric projects such as Size Korea. Therefore, we first compiled a list of relevant industry sectors with a demand for dynamic measurement data and listed representative firms in each industry sector. We then conducted one-on-one interviews to identify the precise postures and measurement points required for dynamic anthropometric assessment, concentrating on posture requirements specific to each industry. Furthermore, we convened a consultative session with anthropometric specialists to confirm high-demand postures and necessary measurement points. The research outcomes identified four principal postures: daily working posture, maximum bending posture, seated work posture, and stair-climbing posture, which represent a range of daily movements. Further, the shoulder, elbow, and neck joint flexion were identified as critical measurement points. These findings are anticipated to substantiate the application of human measurement data in motion, satisfying a wide variety of industrial demands in product design and development practices.

• Proceedings of the KIEE Conference
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• 1994.07a
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• pp.573-575
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• 1994

Resent research activities and technical trends for UPS(UNINTERRUPTIBLE POWER SUPPLY) are reviewed. There are increasing demands for UPS to get mote useful performance. This needs are high-efficiency, high-confidency, high-quality, low-cost. self-diagnosis. maintenance-free, and a wide variety of options. These can be satisfied with high-technology and optimal system coordination. In this paper. according to these demands. a newly developed UPS and a wide variety of options are introduced. Also. the data related are presented.

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.665-674
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• 2020

Objectives: This study investigated the perception and educational needs of the health care professionals in wake of the fourth industrial revolution. Methods: This study was conducted among 115 students from the Department of Dental Hygiene and 122 dental hygienists from Gwangju and Jeonnam, from June 25 to September 20, 2020. The questionnaire consisted of one question on the perception of the concept of the fourth industrial revolution and two questions on the influence of the fourth industrial revolution. It contained a total of eight questions on the desired education hours and education expenditure. Results: The degree of perception of the concept and influence of the fourth industrial revolution was 3.20 for both dental hygiene students and dental hygienists; the average of the two groups was the same. Regarding the educational experience, 'no experience' was the most marked response among both dental hygiene students and dental hygienists and no statistically significant difference was observed (p>0.05). Conclusions: As demanded by the changing times, it is necessary to identify the differences in educational demands of the two groups, develop educational programs according to the fourth industrial revolution, as demanded by the changing times, and apply educational programs that fit the educational needs of each group.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.2
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• pp.23-32
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• 1993

This paper describes the background and the development of a hydrologic network flow model. The model was development to simulate daily water demand and supply for selected stream reaches within a watershed, and used as a tool for evaluating, simulating, and planning a water resources system. The proposed network flow model considers daily runoff from subareas, various water demands, and diversion structures within each subarea. Daily streamflow at a reach is simulated after balancing the water demands from subareas. The lateral inflow from subareas is simulated using a modified tank model. Total water demands consist of the daily demands for agricultural, domestic, industrial, livestock, fishery, and environmental uses within a rural district. The return flow, diversions from sources and storage components such as reservoirs were also incorporated into the mode l . The developed model is a generalized version that may be applied to different combinations of river reaches for a given system. This may help potential users identify areas where water supply does not suffice the demands for different time horizons.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2793-2800
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• 2010

In this paper, we propose a quadratic (nonlinear) regression model that forecasts daily demands of electric power in summer. For cost-effective production (and/or procurement) of electric power, forecasting demands of electric power with accuracy is important, especially in summer when temperature is high. In the literature, temperature and daily demands of preceding days are typically employed to construct forecasting models. While, we consider another factor, day of the week, together with temperature and daily demands of preceding days. For validating the proposed model, we demonstrate the forecasting accuracy in terms of MAPE(Mean Absolute Percentage Error) and MPE(Maximum Percentage Error) using field data from KEPCO(Korea Electric Power Corporation) in comparison with two forecasting models in the literature. When compared with the two benchmarks, the proposed forecasting model performs far better providing MAPE and MPE not exceeding 3.08% and 8.99%, respectively, in summer from 2005 to 2009.

• Journal of Korean Institute of Industrial Engineers
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• v.14 no.1
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• pp.119-131
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• 1988

Vehicle Scheduling Problem (VSP) is a generic name given to a whole class of problems involving the visiting of "stations" by "vehicles," where a time is associated with each activity. The studies performed to date have the common feature of a single objective while satisfying a set of restrictions and known customer supplies or demands. However, VSPs may involve relevant multiple objectives and probabilistic supplies or demands at stations, creating multicriteria stochastic VSPs. This paper proposes a heuristic algorithm based on goal programming approach to schedule the most satisfactory vehicle routes of a bicriteria VSP with probabilistic supplies at stations. The two relevant objectives are the minimization of the expected travel distance of vehicles and the minimization of the due time violation for collection service at stations by vehicles. The algorithm developed consists of three major stages. In the first stage, an artificial capacity of vehicle is determined, on the basis of decision maker's subjective estimates. The second one clusters a set of stations into subsets by applying an efficient cluster method developed. In the third one, the stations in each subset are scheduled by applying an iterative goal programming heuristic procedure to each cluster.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.191-194
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• 2005

Over the past decade, changes in product development processes and increased consumer demands have dramatically influenced engineering working practices and targets. The information technology revolution has made its appearance concurrent to this relentless escalation in product engineering requirement. It has offered hopes for improved productivity despite these increasing demands. The wide availability of personal computing power, virtually inexhaustible sources of information and an abundance of computerized engineering tools have created great expectations. Knowledge information modeling system and database were developed using ASP and Microsoft SQL 2000 Server to share the DB that can be utilized to process on the web.