• Membrane and Water Treatment
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• v.3 no.1
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• pp.63-76
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• 2012

Mother liquid discharged from a salt-manufacturing plant was electrodialyzed at 25 and $40^{\circ}C$ in a continuous process integrated with $SO_4{^{2-}}$ ion low-permeable anion-exchange membranes to remove $Na_2SO_4$ and recover NaCl in the mother liquid. Performance of electrodialysis was evaluated by measuring ion concentration in a concentrated solution, permselectivity coefficient of $SO_4{^{2-}}$ ions against $Cl^-$ ions, current efficiency, cell voltage, energy consumption to obtain one ton of NaCl and membrane pair characteristics. The permselectivity coefficient of $SO_4{^{2-}}$ ions against $Cl^-$ ions was low enough particularly at $40^{\circ}C$ and $SO_4{^{2-}}$ transport across anion-exchange membranes was prevented successfully. Applying the overall mass transport equation, $Cl^-$ ion and $SO_4{^{2-}}$ ion transport across anion-exchange membranes is evaluated. $SO_4{^{2-}}$ ion transport number is decreased due to the decrease of electro-migration of $SO_4{^{2-}}$ ions across the anion-exchange membranes. $SO_4{^{2-}}$ ion concentration in desalting cells becomes higher than that in concentration cells and $SO_4{^{2-}}$ ion diffusion is accelerated across the anion-exchange membranes from desalting cells toward concentrating cells.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.636-639
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• 2002

In the paper, a Visual factory model for a optical-components manufacturing process is built. The optical-components manufacturing process is composed of 3 operation processes; optical sub assembly process, package assembly process, and fiber assembly process. Each process is managed not a batch mode, which is one of most popular manufacturing styles to produce a great deal of industrial output, but though a modular cell. In the processes, a modular cell has to be processed independently of the other cells. Optimization for the composition of assembly cell in the optical-components system is made by the Visual factory model.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.04b
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• pp.380-385
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• 1993

The demand for automatic manufacturing systems is incerasing. Computer Integrated Manufacturing(CIM) technology is believed to be a solution for the problem to enhance productivities and flexibilities. Although researches on CIM have been conducted treendously, application of the technology is not widely accepted yet. The CIM research on the shop floor starts with the Flexible Manufacturing System(FMS). One of the crucial obstacles to the FMS is the lack of excellent strategies for efficient operations. The aim of this research is constructing an automation scheme in the low level of factories where various machinaries are involved. An operating strategy is established for an automation unit named as a cell which resides between the upper level computers and manufacturing shop floor. The cell is defined to fit into the total manufacturing system. The defined cell has more functions than conventional cells. A scheduling scheme is adopted for the shop floor operations. A set of software has been developed and tested through simulations and shop floor experiments.

• Korean Management Science Review
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• v.12 no.1
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• pp.51-60
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• 1995

This paper presents a workload based model and cell design support system (CDSS) in manufacturing cell design. The proposed model consider manufacturing factor such as machine capacity, production volume, process time, and cell size. Based on those information, workload is calculated and according to the workload, the relationship between machine and part is represented by the workload matrix. To form the manufacturing cell, correlation similarity coefficient (CSC) among machines are calculated and a pair of machines that has the highest value of CSC is assigned to a machine cell. Repeat the above steps until the desired manufacturing cells are obtained. Finally, a cell design support system that could increase the efficiency in the application of a proposed model is developed. The proposed model and CDSS are illustrated by a numerical example.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.4
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• pp.386-394
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• 2012

Recent trends in the flexible manufacturing systems are morphing cell control for the shop-wide production operation system and providing the integrated operation and execution system together with vendor-specific FMC/FMS platform. In these requirements, the shop-floor level operation system plays a role of coordinating the control activity of each cell, and has to provide flexibility for the complexity of mixed operations of various cells. This paper suggests a system architecture for the mixed environments of multi-cells and job shop, its corresponding enabling technologies based on comparative studies with other related studies and commercialized systems. This approach includes a process definition model considering the integration with upper BOM-BOP and external service modules, and reconfigurable device-level interface which provides dynamic interconnections with machine tools and cell controllers. The function modules and their implementation results are also described to provide the feasibility of the proposed approaches as the flexible shop-floor operation system for the multi-cell environments.

• Journal of Surface Science and Engineering
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• v.51 no.1
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• pp.40-46
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• 2018

The light-weight of the research and development materials is actively carried out by overseas automobile companies and technology development continues in Korea. For the sake of fuel efficiency, the development of lightweight technology by improving the manufacturing method has been very effective. Recently, to maximize the effects of light weight, automotive interior parts have been applied by the micro-cellular injection molding using supercritical fluids and we call the Mucell manufacturing. This technique causes a problem in the quality of the surface of the products, because the shooting cells are revealed as the surface layer of the products by forming micro cells at the center of the products during injection molding. To overcome these phenomenon, we increased the temperature of injection molding using joule heating until critical value. In this study, we have predicted the problem of Mucell injection molding through the finite element analysis as changed the temperature by joule heating. From the result of finite element analysis, we have determined the optimized process and made the injection mold included electric current heating system with Mucell manufacturing analyzed the surface characteristics of the injection product according to changing mold temperature.

• IE interfaces
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• v.12 no.1
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• pp.10-18
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• 1999

Job shop manufacturing environments are using the concept of cellular manufacturing systems(CMS) which has several advantages in reducing production lead times, setup times, work-in-process, etc. Utilizing the similarities between cell-machine, part-machine, and the shape/size of parts, CMS can group machines and parts resulting in improved efficiency of this system. However, when grouping machines and parts in machine cells, there inevitably occurs exceptional elements(EEs), which can not operate in the same machine cell. Minimizing these EEs in CMS is a critical point that improving production efficiency. Constraints in machine duplication cost, machining process technology, machining capability, and factory space limitations are main problems that prevent achiving the goal of maintaining an ideal CMS environment. This paper presents an algorithm that minimizes EEs under the constraints of machine duplication cost and factory space limitation. Developing exceptional operation similarity(EOS) by cell-machine incidence matrix and part-machine incidence matrix, it brings the machine cells that operate the parts or not. A mathematical model to minimize machine duplication is developed by EOS, followed by a heuristic algorithm in order to reflect dynamic situation resulting from minimizing exceptional elements process and the mathematical model. A numerical example is provided to illustrate the algorithm.

• The Korea Journal of Herbology
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• v.24 no.3
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• pp.51-58
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• 2009

Objectives : This study was conducted to evaluate the antioxidative and anticancer activity of the water and ethanol extracts from pickled soybean products by manufacturing stage. Methods : Yakkong (YK) was pickled for 15 days to prepare Chokong (CK) and Chokong pills (CKP) were mixed Chokong (CK) powder with vinegar. Herbal Chokong pills (HCKP) were made by addition five kinds of medicinal herbs to Chokong. Pickled soybean products by each manufacturing process were extracted with distilled water and 70% ethanol, and the extracts were tested for their antioxidative and anticancer activities. Results : The highest electron donating abilities (EDA) of the water and ethanol extracts were from HCKP among pickled soybean products and those were 81.2% and 91.5% at 1,000 $\mu$g/mL, respectively. The ethanol extracts of pickled soybean products had higher activities of EDA and superoxide dismutase (SOD) than water extracts. The highest anticancer activity was the water extracts of HCKP against both of MDA and A549 cells. Conclusions : These results suggest that herbal Chokong pills (HCKP) can be used as natural antioxidant to prevent oxidative damage in normal cells probably because of their antioxidative characteristics.

• Biomaterials and Biomechanics in Bioengineering
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• v.1 no.2
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• pp.81-93
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• 2014

An in vitro cell study evaluating cell adhesion to hydroxyapatite (HA) coated prosthetic Ti-6Al-4V alloy via laser treatment is presented in comparison with uncoated alloy. Based on our previous in vitro biocompatibility study, which demonstrated higher cell attachment and proliferation with MC3T3-E1 preosteoblast cells, the present investigation aims to reveal the effect of laser coating Ti alloy with HA on the adhesion strength of bone-forming cells against centrifugal forces. Remaining cells on different substrates after centrifugation were visualized using fluorescent staining. Semi-quantifications on the numbers of cells were conducted based on fluorescent images, which demonstrated higher numbers of cells retained on HA laser treated substrates post centrifugation. The results indicate potential increase in the normalized maximum force required to displace cells from HA coated surfaces versus uncoated control surface. The possible mechanisms that govern the enhancing effect were discussed, including surface roughness, chemistry, wettability, and protein adsorption. The improvement in cell adhesion through laser treatment with a biomimetic coating could be useful in reducing tissue damage at the prosthetic to bone junction and minimizing the loosening of prosthetics over time.

• Journal of the Korean Society of Food Culture
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• v.32 no.5
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• pp.453-464
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• 2017

Vegetable soup has been reported to have anti-inflammatory, anti-oxidative and anti-cancer effects. In this study, five kinds of vegetable soup were developed using a new manufacturing process and compositional changes in raw material, and anti-cancer and immuno-stimulatory activities were evaluated. Cytotoxicity tests based on MTT assay revealed that all vegetable soups had strong inhibitory effects against CT26 mouse colon cancer cells, with soups including Solomon's seal being most effective based on comparison of $IC_{50}$ values. Apoptosis in response to vegetable soup was occurred by 3-5 fold on cancer cells compared to normal cells. Mouse splenocytes increased by 266-541% in response to addition of vegetable soup in an in vitro proliferation experiment. In co-culture with splenocytes and CT26 cancer cells, splenocytes increased by more than 280% in every vegetable soup treatment, while cancer cells decreased by about 60% and cytokines such as $IFN- {\gamma}$ and IL-12 were secreted from splenocytes in high levels only in response to vegetable soup including Solomon's seal. In conclusion, all vegetable soups developed in this study had anti-cancer effects, and vegetable soup including Solomon's seal showed the strongest anti-cancer and immuno-stimulatory effects. These results suggest that functionality of vegetable soup could be increased by changes in manufacturing processes and raw materials composition.