• Journal of Korean Society of Environmental Engineers
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• v.39 no.6
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• pp.318-324
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• 2017

We evaluated geosmin and MIB biodegradation and adsorption mechanism of biological activated carbon (BAC) and anthracite biofilter. In steady state of BAC process, the geosmin and MIB were completely removed at the 30 min empty bed contact time (EBCT) even though low water temperature ($9^{\circ}C$) in which the activity of attached bacteria decreased. When the water temperature was $26^{\circ}C$, the microbial biomass and activity were higher at the upper layer of the biofilm than at $9^{\circ}C$, and the microbial biomass and activity decreased as the depth was deeper. This is because when the water temperature is high, the biodegradable organic matter (BOM) removal rate in the upper layer is high and the BOM amount that can't be supplied to the lower layer. The Removal rate of geosmin and MIB by BAC process did not show a significant difference compare to activity-inhibited BAC by treated with azide and the biofilter also removed the geosmin and MIB by biological action. It means geosmin and MIB could be removed by competitive relationship between adsorption and biodegradation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.4
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• pp.149-158
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• 2015

Up-to-date manufacturing companies have faced a market-driven environment of pull production order. There should be a difference in operating manufacturing resources according to the type, quantity, and delivery time of manufactured products, because the process situation in pull production is changed by customer orders. And it should be taken into account from the stage of preparing for production such as process design and the placement and utilization of manufacturing resources. However, the feasibility of production plans is limited because most of small manufacturing businesses make production/supply plan of the parts and products assuming that equipment abilities in scheduling is sufficient without managing process standard information systemically. In this study, a discrete event simulation system based on BOM (bill of material), that is F-OPIS (online productivity innovation system), is introduced and a case study on application of the system leading to improving productivities is presented. F-OPIS deals with a decision-problem on production management and it is specialized for small-and- medium sized manufacturing companies. The target company of this case study is a typical small-and-medium sized manufacturing company in Korea, that produces various machined parts. The target company adopts make-to-stock production management to prevent tardy delivery because of fluctuations in demand. Therefore, it is required to apply an efficient inventory control solution for improving productivities. In this paper, based on the constraints of working capacity of manufacturing resources, the bottleneck process is analyzed as production conditions are changed. Consequently, an improvement plan is proposed, that eventually enhances overall utilization rates of resources in the bottleneck process and reduces overall production lead-time and inventory level.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.1
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• pp.92-100
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• 2008

This paper develops a process monitoring system for real-time process control. The practical case is studied on a small and medium marine equipment company. For business process reengineering of the company, we adopt an approach based on information engineering methodology, which consists of four stages : planning, analysis, design, and implementation. The system is developed for Client/Server environment. We discuss the constructing of hardware system for real-time process control at low cost. The developed system is composed of interrelated modules for item master and BOM management, process control, facility management, SQC and work report.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1870-1873
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• 2004

The objective of this study is to investigate the possibility of chemical process synthesis purely based on mathematical programming when given an objective, feed conditions, product specifications, and model equations for available process units. A method based on a state space approach is proposed, and applied to an example problem with a reactor, a heat exchanger, and a separator. The results indicate that a computer can automatically synthesize an optimal process without any heuristics or expertise in process design provided that global optimization techniques are improved to be suitable for large problems.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.415-424
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• 2020

Recently, the elevator industry in Korea has been divided into the high speed elevator market and medium-low speed elevator market, and SMEs are making rapid progress in the medium-low speed fields. Usually, since the elevator manufacturer receives an order for installation after the construction of the building structure, it is necessary to promptly create a optimal elevator model and layout drawing in an earlier stage of sales activity due to the limited time to elevator installation. This study analyzes the sale and design works of the elevator SMEs, examines the areas that can be efficiently improved, and integrates the preceding our studies from the viewpoint of efficiency improvements at sales and design business process in the elevator industry. After that, we proposed an integrated framework of sales and design process for the elevator SMEs industry, and developed a prototype software system for automating the creation of optimal elevator model, layout drawing of elevator and BOM(Bill Of Material) list.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.3
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• pp.207-214
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• 2011

Ship design requirements described in the building specification should be reflected in the design process. This paper identifies the configuration of requirements mentioned in the building specification using Ontology Representation Language (OWL). Ontology-based semantic search system specifies the requirement items. Through this extraction, building specifications mentioned for each entry are configured to the tree. Tracking requirements for ship design and a set of procedures to instruct is also used for the V model of systems engineering. The semantic search engine of robot agent and ontology can search the requirements specification document and extract the design information. Thereafter, design requirements for the tracking model that proposes the relationship between the associated BOM(bill of material) and product structure.

• Journal of the Semiconductor & Display Technology
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• v.17 no.3
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• pp.10-16
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• 2018

In silicon crystalline PV (Photo Voltaic) industry, PV module or panel electric power is directly related to the companies' profit. Thus, many PV companies have invested and focused on R&D activities to get the higher module power. The main BOM (Bills of Material) on the module consists of PV solar cell, ribbon, EVA (Ethylene-Vinyl Acetate copolymer), glass and back sheet. Based on consistent research efforts on enhancing module power using BOM, there have been increase of around 5 watt per module every year as results. However, there are lack of studies related to enhancing accuracy of measurement. In this study, the enhancing on the metrology is investigated and the improvement shows actually contribution to company's profit. Especially, the measurement issues related to heat and to quasi state of bandgap diagram by EL(Electro Luminescence) are described in this study.

• Korean Management Science Review
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• v.18 no.2
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• pp.1-10
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• 2001

Due to environmental change in market, delivery satisfaction to customer end redaction of LeadTime are critical In the Make-to-Order manufacturing system. This paper focuses on Order Feasibility Decision System Based on SNS System. We suggest BOP (Bill of Process) in which aggregated information is used When the load p1anning problem is solved while more detailed information is used when the scheduling problem is solved.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.170.5-170
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• 2001

As close competitions are being fought out among enterprises, they should accomplish their objectives such as reduction of cost, improvement of quality and condensation of due date, etc. For this objects, it becomes very important to manage the workflow harmoniously and to share the information efficiently between geographically dispersed users. We developed the collaborative design system, which manages various design process and enables to share design information. In this paper, Internal-based collaboration system for press die design process in the automobile manufacturer is developed with CORBA, Java and relational database system. After modeling real press die design process with UML language, workflow routing path is created by modeling data. Cost and time for ...

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.2
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• pp.72-78
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• 2020

Demand for cosmetics with functionality and eco-friendliness has increased dramatically due to recent aging, well-being trends, and increased interest in beauty. Cosmetics production in 2014 was 8,970.4 billion won, an increase of about 50% compared to 6,014.6 billion won in 2010. In the midst of this, similar companies in intense competition are pursuing differentiated strategies and innovation activities to solve quality, price and delivery problems. In particular, cosmetics packaging work is getting more difficult due to the increasing bill of materials (BOM) and difficult assembly methods. Therefore, in this study, the following problems were identified and suggestions for the improvement of the packaging Many research laboratories such as biotechnology, chemistry, and pharmaceuticals, which are undergoing various studies, are equipped with ready-made laboratory safety equipments such as bio-safety workbenches, aseptic bases, and exhaust workbenches. However, most researchers are disadvantaged in using existing safety equipment. This is because existing safety equipment can not take into account all of the unique characteristics of the research. For this reason, researchers are demanding the development of customized safety equipment that is well suited to their research needs. process of Company C, which is facing difficult situation to respond to the customer 's delivery due to the 52 - hour work week. First, we used the stopwatch to find the difficulty process in the packaging process and show ways to improve it. Second, to improve the efficiency of line balancing in the packaging process, we integrate processes, improve work methods, and perform simple automation. As a result, the prepare loss for replacement was reduced by 1 minute from 5 minutes, resulting in a 23% increase in productivity from 112 ea./hour to 137ea./ hour per person. At this time, the LOB of the packaging process was improved from 70% to 82% by operating one more production line through one person per line, total 9 people saving.