• Industrial Engineering and Management Systems
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• v.14 no.4
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• pp.401-412
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• 2015

In this paper, we present a modeling approach to production planning for an actual production line and a heuristic method. We also illustrate the successful implementation of the proposed method on the production line. A heuristic algorithm called the push-back algorithm was designed for a single machine earliness/tardiness production planning with distinct due date. It was developed by combining a minimum slack time rule and shortest processing time rule with a push-back procedure. The results of a numerical experiment on the heuristic's performance are presented in comparison with the results of IBM ILOG CPLEX. The proposed algorithm was applied to an actual case of production planning at Woongjin Chemical, a leading manufacturer of filter products in South Korea. The seven-month execution of our algorithm led to a 24.5% decrease in the company's inventory level, thus demonstrating its practicality and effectiveness.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.4
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• pp.54-71
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• 2005

Purpose : The purpose of this research was to investigate the effects of Saurui Herba Seu Rhizoma(SHSR) on Anti-inflammatory properties in Raw264.7 cell line and murine models of inflammation. Methods : To investigate the effects of Saurui Herba Seu Rhizoma(SHSR) on anti-inflammation, we study cytotoxicity effects of SHSR on Mouse Lung Fibroblast Cells and Peritoneal Macrophages, Inhibitory effects of SHSR on the nitric oxide (NO) release, the ROS production, and the interleukin-6 production. Results : The cytotoxicity of SHSR on mouse lung fibroblast Cells and Raw264.7 cell line was not observed. SHSR in RAW264.7 cell line inhibited $IL-1{\beta}$, IL-6 mRNA gene expression depending upon the concentrations of extract and inhibited IL-18 mRNA gene expression at 100 ${\mu}g/ml$ of extract. SHSR in RAW264.7 cell line inhibit COX-2 mRNA gene expression at 100, 10 ${\mu}g/ml$ of extract. SHSR in RAW264.7 cell line inhibited NOS-II mRNA gene expression depending upon the concentrations of extract. SHSR in RAW264.7 cell line didn't inhibit $TNF-{\alpha}$ mRNA　gene expression. SHSR in RAW264.7 cell line decreased IL-6 production depending　upon the concentrations of extract. SHSR in RAW264.7 cell line decreased $ITNF-{\alpha}$ production according to the concentrations of extract. SHSR in RAW264.7 cell line inhibited NO release specially SHSR 100, 10 ${\mu}g/ml$ concentrations of extract. SHSR inhibit ROS production depending upon the concentrations of extract. Conclusion : These results suggest that SHSR can be used treating a lot of women disease caused by inflammation.

• Industrial Engineering and Management Systems
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• v.8 no.3
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• pp.131-138
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• 2009

The variable sampling inspection scheme with screening for the purpose of assuring the upper limit of maximum expected surplus loss after inspection has been proposed. In this inspection scheme, it has been assumed that a product lot consists of products manufactured through a single production line and lot quality characteristics follow a normal distribution. In the previous literature with respect to inspection schemes, it has been commonly assumed that lot quality characteristics obey a single normal distribution under the condition that all products are manufactured in the same condition. On the other hand, the production line is designed in order that the workload of respective processes becomes uniform from the viewpoint of line balancing. One of the solutions for the bottleneck process is to arrange the workshops in parallel. The lot quality characteristics from such a production line with the process consisting of some parallel workshops might not follow strictly the single normal distribution. Therefore, we expand an applicable scope of the above mentioned variable sampling inspection scheme with screening in this article. Concretely, we consider the variable sampling inspection with screening for the purpose of assuring the upper limit of average outgoing surplus quality loss in the production lots when the lot quality follows the mixed normal distribution.

• Journal of the Korea Society for Simulation
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• v.5 no.2
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• pp.1-12
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• 1996

Utilizing the simulation approaches, the dynamic production scheduling system FOLS(Flexible flowshop On-Line Simulation) is developed under the flexible flowshop environment. When an interruption such as machine failure/recovery is occurred at the shop floor, the FOLS system performs evaluations for job selection rule oriented alternatives, and generates a dynamic production schedule based on the collected current shop floor data. For the case study, the FOLS system is applied to the printed circuit card assembly(PCCA) line and simulation results are reported.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.115-121
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• 1995

The objective of this study is to develope an effectiveness measurement technique for U-shaped JIT production line by computer simulation. A small and medium sized automobile brake master cylinder manufacturing plant is studied for productivity improvement The production line is analysed and improved by applying Low Cost Automation, special jigs and fixtures, and facilities layout changes. An experimental simulation model is built using SIMAN(SIMulation ANalysis) simulation software for the production system analysis.

• BMB Reports
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• v.57 no.2
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• pp.86-91
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• 2024

The fatty acids content of castor (Ricinus communis L.) seed oil is 80-90% ricinoleic acid, which is a hydroxy fatty acid (HFA). The structures and functional groups of HFAs are different from those of common fatty acids and are useful for various industrial applications. However, castor seeds contain the toxin ricin and an allergenic protein, which limit their cultivation. Accordingly, many researchers are conducting studies to enhance the production of HFAs in Arabidopsis thaliana, a model plant for oil crops. Oleate 12-hydroxylase from castor (RcFAH12), which synthesizes HFA (18:1-OH), was transformed into an Arabidopsis fae1 mutant, resulting in the CL37 line producing a maximum of 17% HFA content. In addition, castor phospholipid:diacylglycerol acyltransferase 1-2 (RcPDAT1-2), which catalyzes the production of triacylglycerol by transferring HFA from phosphatidylcholine to diacylglycerol, was transformed into the CL37 line to develop a P327 line that produces 25% HFA. In this study, we investigated changes in HFA content when endogenous Arabidopsis PDAT1 (AtPDAT1) of the P327 line was edited using the CRISPR/Cas9 technique. The successful mutation resulted in three independent lines with different mutation patterns, which were transmitted until the T4 generation. Fatty acid analysis of the seeds showed that HFA content decreased in all three mutant lines. These findings indicate that AtPDAT1 as well as RcPDAT1-2 in the P327 line are involved in transferring and increasing HFAs to triacylglycerol.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.1
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• pp.105-113
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• 1998

This paper deals with a production line which consists of two production stages that are separated by a finite storage buffer. The inventory level in the storage buffer controls the production rate of the preceding stage. That is, the production rate becomes high (low) when the buffer inventory is low (high). We analyze the system characteristics utilizing the Markov process theory and then find an optimal control policy which maximizes a given system profit function. Also, a sensitivity analysis is made to examine the effects of various system parameters on the system performances.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.103-114
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• 2001

In Korean clothing industry, most of the womens wear is manufactured by subcontractors. Because womens fashion is getting more rapidly changing, subcontractors production run of each orders is getting shorter too. Also the volume of each order is quite small compare to mens or childrens. So subcontractors are always in a hurry to adjust their production capacity to new order. Therefore they cannot afford to plan production line and allocate works efficiently enough to manufacture competitive products in terms of cost, lead time, as well as quality. The purpose of this study is to suggest a production planning model for womens apparel manufacture, which are relevant to the situation of Korean clothing industry.

• Journal of the Korea Society for Simulation
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• v.22 no.2
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• pp.93-100
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• 2013

Mixed model production system means that various products are manufactured alternately in a line, and it has become a popular system in the era of multi-product small-quantity production. However, in the mixed model production system using flow line, the unbalance among stations is not inevitable because the workloads of stations cannot be the same. Thus, flow line system has been replaced to cellular manufacturing system for reducing the loss of waiting due to the unbalance of stations. In this paper, we introduce the simulation case study of an automated welding line which produces the parts of excavator. The factory has considered replacing the mixed model flow line to the cellular manufacturing system based on FMC concept. The increase of production quantity is estimated about 26.7%, and the lead time is reduced more than 55%. Furthermore sensitivity analyses are conducted considering the changes of product-mix.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.162-165
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• 2007

TFT-LCD process has two advantages as compared with the semiconductor-process. It is that cycle time is short and number of the final products are small. But it needs complicated inspection / assembly line to be treated manually and much higher labor costs in the TFT-LCD process. Also, It is necessary to build PICS(Production Information and Control System) which is automated and intelligent. In this paper, an automated process of LCD module assembly line that can increase productivity and reduce the cost of production to strengthen the competitiveness corresponding with global market is planned in comparison with its manual/semi-auto. It is noted that The automated line for COG$\sim$FOG process replacing with the existing facilities had the following effects; the productivity is increased to about 1.5 times and labor cost reduced 85%. In addition, whole assembly line can be short and simple.