• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2000년도 춘계학술대회 논문집
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• pp.57-66
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• 2000

Production-distribution planning is the most important part in supply chain management (SCM). To solve this planning problem, either analytic or simulation approach has been developed. However these two approaches have their own demerits in problem solving. In this paper, we propose a hybrid approach which is a specific problem solving procedure combining analytic and simulation method to solve production-distribution problems in supply chain. The machine capacity and distribution capacity constraints in the analytic model are considered as stochastic factors and adjusted by the proposed specific process according to the results from independently developed simulation model which includes general production-distribution characteristics.

• 대한산업공학회지
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• 제17권1호
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• pp.83-94
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• 1991

This study is concerned with the scheduling problem for mixed-model assembly lines in Just-In-Time(JIT) production systems. The most important goal of the scheduling for the mixed-model assembly line in JIT production systems is to keep a constant rate of usage for every part used by the systems. In this study, we develop two heuristic algorithms able to keep a constant rate of usage for every part used by the systems in the single-level and the multi-level. In the single-level, the new algorithm generates sequence schedule by backward tracking and prevents the destruction of sequence schedule which is the weakest point of Miltenburg's algorithms. The new algorithm gives better results in total variations than the Miltenburg's algorithms. In the multi-level, the new algorithm extends the concept of the single-level algorithm and shows more efficient results in total variations than Miltenburg and Sinnamon's algorithms.

• 한국군사과학기술학회지
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• 제2권2호
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• pp.83-91
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• 1999

Dynamic characteristic of manufacturing stage is understood and the utilization of each machine is maximized by developing on-line dynamic CAPP system to consider the overloads in the aircraft part manufacturing line. In this paper, a scheme of production planning and scheduling system was proposed through inspection about some predeveloped CAPP system. Developed production planning and scheduling system included process planning module. After precise inspection of some FMS line schema at domestic heavy industry, optimized FMS line was applied to aircraft part manufacturing and repairing factory. By virtue of considering overloads of factory and machine through on-line dynamic CAPP system, the utilization of resources is maximized and manufacturing lead time is minimized.

• 산업경영시스템학회지
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• 제19권39호
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• pp.255-264
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• 1996

This Paper presents a heuristic algorithm for machine-part group formation considering part production information (Production volume, roution sequence, unit operation time, facility size) in cellular manufacturing logistics system. In general, factory space is restricted within limited size when cells are located. A twofold heuristic algorithm is developed for considering factory space restrictions of located cells. The first phase is a aggregation procedure to minimize inter cell movement for satisfactoring space restriction. The second phase is a rearrangement procedure to maximize line balancing efficiency between machines within the cell and non assigned machine during first phase. Numerical example is presented to verify the efficiency of proposed algorithm.

• 헤리티지:역사와 과학
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• 제35권
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• pp.138-158
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• 2002

To compare and analyze technical system related to manufacturing of ironware during the period of the Three Kingdoms, an analysis was conducted on the minute system of metalwork, as study objects, of the remains of the Mt. Wolpyeong fortress wall in Daejeon in the period of capital during the era of the Three Kingdoms in the 5th century, the Sanwol-ri remains in the 6th century in Gunsan and the remains of ironware excavated from the great ancient tomb of Hwangnam of the Silla dynasty in the 5th century. The result of analysis shows that in the most of the casting products, the minute system of white cast iron were contained. While the iron part of decarbonization was in the system by casting as white cast iron in the central part, on the surface layer it was turned out that comparatively uniform 100% pearlite system of about 1~2mm degree was existing. The part of pearlite on the surface layer was caused by decarbonization, which appears in all the parts of blade front end and handle. Therefore, it was found that the iron part of decarbonization was manufactured by casting, and then was processed at the high temperature by decarbonization. For the products of forging, after processing the products on the basis of pure iron for materials, they manufactured the ironware that raises the strength by carbonizing that keeps carbon infiltrated on the necessary part, by the method of black smith welding that add pure iron to steel, or by varying the method of heat processing onto the part required of strength. Though limited, we could understand that the technical systems for manufacturing skill of ironware in the areas of Baekje and Silla were different each other. In the technical system for Hwangnam great ancient tomb in the Silla area, it is found that they had raised the strength on the necessary part by applying the steelmaking method of carbonizing in the last stage of production of products, in the meantime in Baekje area, it appears that they had produced steel in advance in the first stage of production of the products, and used the produced steel only to the necessary part.

• 한국해양학회지
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• 제29권2호
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• pp.145-151
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• 1994

황해 중동부해역에서 "황해의 해양자원 개발연구"의 일환으로써 1991년 8월과 10 월에 박테리아의 분포에 대해 조사가 시행되었다. 본 연구는 손 등 (1989)에 의해 같 은 해역에서 보고 된 박테리아의 자료를 함께 이용하여, 황해 중동부해역에서 박테리 아의 시.공간적 분포의 특성을 규명하고자 하였다. 전 기간을 통해 황해 중동부해역 에서 나타난 박테리아의 개체수는 0.5.1.9$\times$10/SUP 8/1/SUP -1/ 이었다. 1991년 10월 을 제외하면 황해 중동부해역의 각 정점에서 두 조사기간 및 봄, 여름, 가을의 계절 변화에 따른 박테리아의 개체수 변화는 크지 않음(3.5배 이내)을 나타냈다. 주목할 만 한 결과로는 1991년 10월을 제외한 나머지 기간 동안에 관찰된 박테리아의 개체수는 해양에서 일반적으로 알려진 엽록소, 박테리아 개체수 관계가 제시하는 분포보다 모두 낮게 나아난 것이 었다. 1991년 10월에 관찰된 박테리아의 분포를 조절하는 주요 원인 은 조사기간의 나머지 경우들과는 다른 것으로 생각된다. 1991년 8월에 박테리아 생산 력은 (0.1~2.9 ug C 1/SUP -1/d/SUP -1/)단위 명적당 일차생산량의 18$\pm$11%를 차지하 였다. 제한된 자료이지만 전반적으로 황해 중동부해역은 엽록소 농도에 비해 낮은 박 테리아 개체수와 박테리아 생산력 대 일차생산력의 비율이 낮은 현상을 나타내고 있으 며, 이의 원인 규명이 황해 중동부해역의 박테리아 생태를 이해하는 관건으로 보인다. 관건으로 보인다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.448-451
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• 1986

An automatic welding system is designed for a part of fork lift. The system is composed of articulated type welding robot, welding positioners, shuttle for robot, system controller and welding equipment. From the application of the system, stable weld quality and production cost saving are achieved. In this paper, the hardware features and control structure of the system are presented.

• Journal of Nutrition and Health
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• 제29권10호
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• pp.1105-1111
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• 1996

Breast milk production and factors related to milk production were examined by test-weighting method in the part of Kangwon Province longitudinally from 0.5 to 5 months of postpartum. Milk production of total mothers averaged 639, 789, 871, 843, 848 and 851g/day at 0.5, 1, 2, 3, 4 and 5 months of postpartum respectively. Mean Milk production of multiparae appeared significantly higher than those of primiparac. The number of feed per day showed decreasing trend from 9.6 to 8.4 during the lactation. Mature milk production had a correlation with transitional milk production and no correlation with infants weight at birth, gestational period and weight gain during pregnancy of mothers. The energy, protein and lipid consumption of total mothers had a positive correlation with breast milk production.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.277-286
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• 2000

A total of 21,441 milking records of biweekly test-days were collected from six dairy farms of Almarai company, Saudi Arabia to determine the effect of days open on lactation curve and milk production during the period of 1991 to 1996. These records included cows calved in two seasons: winter, for cows calved from October to March and summer, for cows calved from April to September. Season of calving did not have a significant effect on the last biweekly points of the curve, and this is due to the effect of the evaporative cooling system. Days open had a marked effect on milk production. The difference in milk yield between cows with days open <60 days and days open >150 days was 1,021 liter. Moreover, the difference in milk yield at early lactation decreased from 1,021 to 829 liter as the days open increased from 75 to 125, due to the decrease in the effect of conception on milk production with advancing lactation. These data also showed that the middle part of the curve (105-255) was the least affected part by the variation in days open because the pregnancy effect become more obvious after five months of conception. These data showed that the dairy cattle produce more than 70% of the milk yield during the first 250 days of the lactation curve.

• Asian-Australasian Journal of Animal Sciences
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• 제20권4호
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• pp.511-516
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• 2007

This experiment was conducted to evaluate the effects of differently maturing corn hybrids on silage production and milk production per unit area in the northern part of Japan, where grain development occurs under decreasing ambient temperature. Both hybrids were harvested at the same time. The stages of maturity for the early-maturing hybrids (EH; 80 d relative maturity) and the mid-maturing hybrids (MH; 93 d relative day) were early dent and late dough stage, respectively. The plant yields for MH were higher than those for EH. The dry matter (DM) content of MH was lower than that for EH, and the effluent loss for MH silage was greater than that for EH silage. Therefore, the DM yields of prepared silage per area were similar for both treatments. Twelve multiparous mid-lactation Holstein cows ($58{\pm}13$ days in milk) were fed diets based on EH or MH silage in a crossover design with two 3-week periods. Cows were fed 3 kg of hay crop silage (DM basis) and either EH or MH silage ad libitum, and concentrates were supplied to meet NRC requirement for dairy cows. Silage DM intake for EH was found to be higher (p<0.05) than that for MH (10.0 vs. 9.1 kg/day). Milk production and milk composition for EH were similar to those for MH. Feed efficiency per total feed intake was similar in both treatments, although the feed efficiency per concentrate intake tended to be higher for the EH than that for the MH diet. These results indicate that differences in maturation in corn hybrids affect the effluent production of silage and the silage intake of dairy cows. It may be advantageous to plant early hybrid corn with a reduction in effluent production of silage as well as a reduction in purchased feed costs for dairy cows under the climatic conditions of the northern part of Japan.