• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.1-12
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• 1992

Parallel Genetic Algorithms (GAs) are developed to solve a single machine n-job scheduling problem which is to minimize the sum of absolute deviations of completion times from a common due date. (0, 1) binary scheme is employed to represent the n-job schedule. Two selection methods, best individual selection and simple selection are examined. The effect of crossover operator, due date adjustment mutation and due date adjustment reordering are discussed. The performance of the parallel genetic algorithm is illustrated with some example problems.

• Journal of Korean Society for Quality Management
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• v.19 no.2
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• pp.125-132
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• 1991

This paper is concerned with the flow shop scheduling problems considering different weighted penalty costs for earliness and lateness, and a common due date. The objective of the paper is to develop an efficient heuristic scheduling algorithm for minimizing total penalty costs and for determining the optimal common due date. The positional weight index and, the product sum method are used. A numerical example is given for illustrating the proposed algorithm.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.2
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• pp.7-12
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• 2006

This study considers the problem of scheduling jobs on uniform parallel machines with a common due date. The objective is to minimize the total absolute deviation of job completion times about the common due date. This problem is motivated by the fact that a certain phase of printed circuit board manufacturing is bottleneck and the processing speeds of parallel machines in this phase are uniformly different for all jobs. Optimal properties are proved and a simple polynomial time optimal algorithm is developed.

• Journal of the Korea Furniture Society
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• v.19 no.2
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• pp.130-136
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• 2008

The objective of this study was to date coffin woods of a grave of husband and wife, using the tree rings, which were excavated from Hoamdong, Chungju city in the central area of South Korea. The species of coffin woods was Japanese Red Pine (Pinus densiflora S. et Z.), one of the major conifers growing in Korea. The husband coffin was dated as A.D. 1628. Due to the absence of bark in the wife's coffin, the number of sapwood rings was estimated to obtain the cutting date. The cutting date of wife's one was estimated to be A.D. 1651${\pm}$10. The Jeogori Jacket for women, which was found in the husband coffin, indicates that the husband died earlier than the wife, as the tree-ring dates suggested.

• Journal of Korean Institute of Industrial Engineers
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• v.12 no.1
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• pp.1-11
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• 1986

This research is concerned with n jobs, m parallel identical machines scheduling problem in which all jobs have a common due date. The objective of the research is to develop an optimum scheduling algorithm for determining an optimal job sequence, the optimal value of the common due date and the minimum makespan to minimize total cost. The total cost is based on the common due date cost, the earliness cost, the tardiness cost and the flow time cost of each job in the selected sequence. The optimum scheduling algorithm is developed. A numerical example is given to illustrate the scheduling algorithm.

• Proceedings of the Korea Society for Simulation Conference
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• 2001.10a
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• pp.435-439
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• 2001

In many make-to-order production systems customers ask due date confirmed and kept. Unexpected urgent orders from valuable customers often requires short lead times, which causes existing orders in the production schedule to be delayed so that their confirmed due dates cannot be met. This Imposes significant uncertainty on the production schedule in a supply chain. In this paper, we propose a new concept of capacity reservation as a viable tool for due date promising and suggest its operational alternatives. Simulation results show that the reserved capacity scheme appears to outperform simple FCFS scheduling policy in terms of the number of valuable urgent orders accepted and total profit attained.

• IE interfaces
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• v.14 no.4
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• pp.341-347
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• 2001

This paper describes a real-time manufacturing scheduling system on Internet using DBR(Drum-Buffer-Rope) scheduling method. We intend to change company-oriented manufacturing scheduling, which has been used at most manufacturing companies, to customer-oriented manufacturing scheduling. Customers can not only choose product kinds, quantities and order due dates, but also evaluate optimum order due date by themselves in real-time through internet and then the results will be converted into practical manufacturing scheduling. If the company cannot meet the customer order due date, it will offer reliable and accurate information to the customers by suggesting the earliest order due date. To evaluate the customer order due date in real time, companies should be able to estimate their accurate production capacity. This research uses Goldratt's DBR scheduling method to realize that function. The DBR scheduling does not recognize the production capacity of the whole company, but only of the constraint resources which have a great effect on the company throughput. Thus, it can improve the customer service level as well as the profit by performing more dynamic and reliable scheduling through Internet.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.165-167
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• 2002

Date palm (Phoenix dactylifera) is an important fruit and cash crop in Sultanate of Oman, occupying nearly 60% of the total cultivated area. However, leaf spots caused by Mycosphaerella tassiana, Alternaria spp., and Dreshcleri sp. have become a threat to date palm's cultivation in recent years. In this study, a field experiment was conducted to find out a suitable chemical spray program to control the disease. A prophylactic spray schedule with mancozeb (Dithane M45), copper oxychloride (Champion), and mancozeb+copper (Trimiltox) effectively controlled the disease when applied at a time when the disease severity index (DSI) was low, ranging from 0 to 1.68. Meanwhile, the disease did not decrease, but instead increased gradually, when the fungicide combination was applied when DSI was high, ranging from 1.78 to 5.37. It was concluded that fungicides should be applied at the early stage or before disease initiation in order to control the disease effectively.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.142-145
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• 1998

The experiment was conducted to elucidate the optimum planting data and fertilization level of Aruncus dioicus var. kamtscacus HARA. Plant height was increased as the seeding date was delayed. There was no transparent difference on plant height indifferent fertilization level. Nuber of stems was remarkably increased in the fertilization 14-14-12kg. Fresh leaf yield in the fertilization of 24-18-15kg was incresed about 31% comparing in the fertilization of 14-14-12kg. As a result, the optimum planing date and fertilization level was Jan. 15 and 24-18-15kg per 10a, respectively.

• Journal of Families and Better Life
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• v.23 no.3 s.75
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• pp.137-151
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• 2005

This study was designed to analyze the cyber counseling cases on the university students' date in order to identify the problems they encounter in dating and seek for a direction for education and consulting program to help them solve the problems. A total of 253 cases in cyber counseling about date were analyzed. The findings demonstrated that the university students were short of interpersonal relationship still needed for expressing Intimacy and maintaining the relationship, and poorly coping with the negative emotions such as conflict, anxiety, and boredom. Thus, a variety of human relations training programs needs to be established in the universities to help the students stay in good terms with the counterpart. Plus, cyber counseling and e-mail counseling needs to be activated so as to allow the university students to easily access when they come to face a problem in dating.