• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.50.3-50
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• 2001

Nonlinear feedback control scheme for reactive distillation column has been proposed. The proposed control scheme is derived in the framework of Nonlinear Internal Model Control. The product compositions and liquid and vapor flow rates in sections of the reactive distillation column are estimated from selected tray temperature measurements by an observer. The control scheme is applied to example reactive distillation column in which two products are produced in a single column and the reversible reaction A + B = C + D occurs. The relative volatilities are favorable for reactive distillation so that the reactants are intermediated boilers between the light product C and the heavy product D. Ideal physical properties, kinetics and ...

• Journal of the Korean Society of Food Culture
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• v.10 no.3
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• pp.167-174
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• 1995

A hazard analysis which included watching operations, measuring temperatures of foods throughout preparation and display, and sampling and testing for microorganisms of total plate counts and coliform bacteria was conducted in various phases of product flow of Naeng-myeun (Cold noodles) and Pi-bim bab (mixed rice) prepared at Korean restaurants. Large numbers of total plate counts were counted from the cooked foods after handling and holding. Ingestion of these foods must be considered high risk. Critical control points identified were, pre-preparation, food handling after cooking, and holding on display in product flow of Nang-Meon and pre-preparation, preparation, and holding on display in product flow of Pi-bim bab. It need for effective quality control of Nang-Meon and Pi-bim bab that training program consist of surveillance, education of the staff, standard operation procedures, forbidding dangerous processes and control of critical points.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.05a
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• pp.79-82
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• 1999

This paper presents a study of cold combined forward-backward extrusion product. The case of product with thin wall in piercing process occur defects of deformation and breakdown during piercing process and the center web of product with thin thickness cause flow defect. Such defect is made by the difference of material flow. Methods of the material flow control in the two directions and forming process to remove this flow defect is proposed. The effectiveness of the proposed methods is examined by comparison experiment and finite element simulation.

• Journal of the Korean Society of Food Culture
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• v.11 no.1
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• pp.107-121
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• 1996

This study was carried out to develop the computer-assisted Hazard Analysis and Critical Control Point (HACCP) program for a systematic approach to the identification, assessment and control of hazards for foodservice manager to assure the microbiological quality of food in hospital foodservice operations. Sanitation practices were surveyed and analyzed in the dietetic department of 4 hospitals. Among them, one 762-bed general hospital was selected as standard model to develop computer-assisted HACCP program. All data base files and processing programs were created by using Foxpro package for easy access of HACCP concept. HACCP program was developed based on the methods suggested by NACMCF, IAMFES and Bryan. This program consisted of two parts: the pre-stage for HACCP study and the implementation stage of the HACCP system. 1. Pre-stage for HACCP study includes the selection of menu item, the development of the HACCP recipe, the construction of a product flow diagram, and printing the HACCP recipe and a product flow diagram. A menu item for HACCP study can be selected from the menu item lists classified by cooking methods. HACCP recipe includes ingredients, their amount and cooking procedure. A flow diagram is constructed based on the HACCP recipe. The HACCP recipe and a product flow diagram are printed out. 2. Implementation of HACCP study includes the identification of microbiological hazards, the determination of critical control points, the establishment of control methods of each hazard, and the complementation of data base file. Potentially hazardous ingredients are determined and microbiological hazards are identified in each phase of the product flow. Critical control points (CCPs) are identified by applying CCP decision trees for ingredients and each process stage. After hazards and CCPs are identified, criteria, monitoring system, corrective action plan, record-keeping system and verification methods are established. When the HACCP study is complemented, HACCP study result forms are printed out. HACCP data base file can be either added, corrected or deleted.

• Korean journal of food and cookery science
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• v.20 no.3
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• pp.292-298
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• 2004

This study researched the microbial change of quality according to various phases of product flow of Dongtae-Jeon (a pan-fried dish) and rolled egg in packaged meals. In order to carry out the study, the time required, temperature, water activity and microbial quality were measured at various phases of production flow of Dongtae-Jeon and rolled egg in packaged meals, and the effects of these factors on microbial multiplication was analyzed. According to the phases in product flow of Dongtae-Jeon, it was shown that the time required is 12.5hrs and water activity is distributed 0.932-0.980. These conditions were suitable for microbial multiplication. According to the phases in product flow of rolled egg, it was shown that the time required is 3.3hrs. In addition, qualitative analysis of pathogenic microorganisms (Salmonella spp., Vibrio parahaemolyticus, Staphylococcus aureus) detected no such microorganisms in any of the samples.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.142-149
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• 2002

In this paper, the metal forming process is caused of rise of the unit cost of production in increase of the lead-time and cost because of manufacturing final product through a few the number of processes. Flow control complex forming is proposed to put into formulation in order to apply cold forging from conventional approximate similarity theory, and the forming loads of the real material(AISI 1008) can be calculated by put at the new similarity formula the load by plasticine model material experiment through hub clutch. In order to reduce lead-time and cost the technology is used to manufacture with lower die of this product. By the application synthetic resin as the raw material, it is have the merit such short lead-time, low cost, good surface finish etc., as compared with the machine work.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.3
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• pp.240-246
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• 2022

This study was conducted to develop a domestic product for a flow control valve for a hydrogen refueling station, and a domestic prototype was manufactured and the durability performance evaluation was conducted through comparison with an imported products. The stress generated by the internal pressure was checked and safety was confirmed using a commercial structural analysis program, ABAQUS, in accordance with the withstand pressure test standards. In addition, after identifying the weak areas the fatigue life was predicted through a commercial software, fe-safe. This fatigue analysis showed that the hydrogen gas repeated test criteria were satisfied.

• Transactions of The Korea Fluid Power Systems Society
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• v.7 no.4
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• pp.39-43
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• 2010

The flow regulators we widely use have some disadvantages. They have a constant flow within each regulator and an inaccuracy with extruding capillary. In this study, we have developed a new type of regulator which was made up of two different capillary tubes overlapped each other. The developed regulator can vary and control the amount of flow. The design parameters of the developed regulator are obtained by using the analytical software. We have proved that the developed regulator can control flow properly through making a trial product and experiment.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.6
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• pp.86-95
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• 2002

This paper suggests the new technology to control metal flow in order to reduce the number of preforming and the machining for the cold forged product with complex geometry. This technology is the combined forming that consists of bulk and sheet forming with double action dies. To analyze the process, finite element simulation has been performed. The proposed technology is applied to hub model that is part of air conditioner clutch. The purpose of this study is to investigate the material now of hub through the relative-velocity control of punch and mandrel using the flow control forming technique.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1272-1281
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• 2006

RFID 기술을 이용함으로써 얻을 수 있는 많은 장점으로 인하여, 공급망에서 발생하는 실시간 제품 정보를 수집하고 관리하기 위하여 RFID 기술이 도입되고 있다. 기존의 RFID 기반의 공급망 관리 시스템은 제품의 위치에 따른 가시성은 확보할 수 있지만, 제품의 모든 상태에 따른 가시성은 확보하지 못한다는 단점이 있다. 이러한 단점을 해결하기 위해, 본 논문에서는 공급망 상의 제품 이동을 계획하고, 제품이 계획에 따라 이동할 때 발생하는 정보를 실시간으로 모니터링하고 통제할 수 있는 제품 상태 기반의 물류 통제 시스템을 설계하고 개발하였다. 이를 위해 본 연구에서는 첫째, 공급망에서 발생하는 제품 상태의 정의와 상태 변화의 흐름을 state chart로 표현하고, 둘째, 공급망에서의 폐쇄형관리 패러다임을 통한 제품 통제(감시 및 예외처리)를 정의하였으며, 셋째, Temporal data modeling을 통해 RFID 데이터 기반의 Database를 설계하고, 마지막으로, Publish/Subscribe 모델을 통해 효율적인 제품 상태 기반의 물류 통제 시스템 아키텍처를 설계하였다.