• IE interfaces
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• v.15 no.1
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• pp.99-106
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• 2002

A recently developed alternative to traditional production planning and control systems such as material requirement planning(MRP) and just-in-time(JIT) is the drum-buffer-rope(DBR). The DBR now being implemented in growing number of manufacturing organizations enables better scheduling and decision making on the shop floor. In implementing the DBR, however, an information system is usually needed to transmit the signal that runs from the constraint to material release. In this paper we propose a different mechanism to transmit the signal in the case that the demand of product is stable, which uses the well-known Kanban system. To improve the reality, this paper shows and example of the Kanban format, its operation, and calculation of the number of Kanbans.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.259-262
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• 1998

DNC(Distributed Numerical controller)는 제품을 생산하기 위해 현장용 컴퓨터를 이용하여 공작기계 및 주변장치를 제어하고 감시한다. 본 논문에서는 SFC/OP(Shop Floor Control/point of Production) 시스템과 연계시키기 위한 DNC 시스템의 구조를 제시한다. 본 시스템은 도면 정보를 유기적으로 연결하여 작업절차서를 조회하고, 작업절차서 및 NC 프로그램/공구 보정 데이타를 인덱스 데이터베이스화하고, 소재·지그·공구를 연계한다. 또한 생산정보를 빠르고 능동적으로 현장 작업자에게 전달하고, 기계의 상태정보를 기계로부터 직접 수집함으로써 실시간 모니터링이 가능하다. 분석 및 설계단계에서는 실시간으로 발생하는 이벤트를 처리하기 위해 상태전이도(State Transition Diagram)를 사용한다. 서버 DBMS(Database Management System)로 관계형 데이터베이스를 채택한 Oracle을 사용하였고, 프로그램 개발도구로는 Developer 2000, Microsoft Visual C++ 5.0을 사용하여 구현한다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.23 no.57
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• pp.21-39
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• 2000

BOM(Bill of Materials) is a listing or description of raw materials, parts, and assemblies that define a product. In manufacturing companies that produce various products with short life cycles, it is very important to manage the BOM of products with various options and versions efficiently. BOM information should be required to share among the departments of engineering, production control, material purchasing, cost management, and shop floor within a manufacturing company. In order to share BOM information efficiently, information system based on WWW(World Wide Web) should be developed. Thus, this paper models and implements Web-based Generic BOM Management System (WGBMS) for management of a number of variant products which are consisted of standard parts under ATO(Assemble To Order) production environment. Also, object-oriented methodology was used to model a generic BOM and phases of navigational design and interface design were introduced to implement the prototype of WGBMS. And Object-Relational Database Management System (ORDBMS) was used to construct the WGBMS database.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.299-299
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• 2000

In this paper, a determination method of number of AGVs fer introducing to the multi-path material handling systems is presented by using genetic algorithm. For serving the raw material to each work stations automatically, there needs to introduce a AGVs for transfer the raw martial. To reduce the overall production cost in the material handling systems, however, a trade off exists between the amount of inventory hold on the shop floor and the number of AGVs needed to provide adequate service. In this paper, firstly a objective function which included the net present fixed costs of each stations and each purchased AGVs, delivering cost. stock inventory cost, and safety stock inventory cost is presented. Secondly by using genetic algorithm, the optimal reorder quantity at each stations is decided, where the number of AGVs is increased step by step. From a simulation with different GA parameters, we can determine a optimal number of AGVs to reduce the overall production cost. Thus, the effectiveness of GA for determining the number of AGVs is verified in automated material handling systems.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.2
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• pp.150-161
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• 1999

This paper deals with the design and development of a real-time integrated communication architecture for heterarchical SFCS(Shop Floor Control System). In autonomous agent-based heterarchical SFCS, each functional unit of parts and resources is equipped with an intelligent controller (agent) that acts as the representative of the entity. The controllers communicate and negotiate with other controllers on a real-time basis through message passing and bidding protocol to achieve mutual agreements for task sharing. ICPL(Integrated Communication Protocol and Language) is proposed for this purpose. ICPL is a language and a protocol for supporting communication among intelligent controllers. Based on the speech act theory, this paper proposes a semantic description for ICPL that associates the description of the cognitive states of controllers with the use of language primitives (message_type). Semantics for the basic set of ICPL messages is described. Eventually, an ICPL-based communication architecture can provide the implementation of the distributed and heterarchical SFCS, and makes the intelligent controller transparent to the negotiation problem.

• IE interfaces
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• v.13 no.2
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• pp.246-252
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• 2000

As moulds and dies are manufactured through complex processes under the make-to-order production environment, it is very difficult that the manufacturing activities as like observance of the due date, trace of the progress, etc are controlled with a real time. In this paper, a schedule-planning system using the commercial software Microsoft Project 98 is developed to control the procedures of mould and die manufacturing with real time. Once an initial schedule is planned from the BOM information in the intranet, it is rescheduled by data collected from machines on the shop floor. The system is suitable to medium- or small-sized manufacturing companies as well as large-sized ones, because it can be installed with a low cost.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.456-463
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• 1997

Atrium buildings are commonly found in Hong Kong since 1980. Those spaces are usually crowded with people and so fire protection systems have to be installed for providing a safe environment. Smoke control system was identified to be important but no clear design guidelines are available because the smoke filling process was not well-understood. In this paper., Computational Fluid Dynamics(CFD) or fire field model is applied to study the smoke filling pattern in atrium. Two common cases on smoke spreading out from a shop adjacent to the atrium; and with a fire located at the atrium floor itself were considered. Simulations with a modified form of the CFD package TEAM were performed. Application of the predicted results Is illustrated.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.4
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• pp.1-8
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• 2012

The purpose of research is to reveal the basic factors which innovation behaviors is motivated in the small-and-medium sized company for strengthening the competitiveness. This study empirically investigates and I was able to obtain participations of 114 questionnaire, and derived statistics by means of SPSS/PC version 18.0. In this study I found that strategic approach of organization and educational supports are significant to effective shop-floor process control. Also, results of process control are significant to customer satisfaction and business performance.

• The Research Journal of the Costume Culture
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• v.15 no.1 s.66
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• pp.1-12
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• 2007

The purpose of this study is to identify the SPA(Specialty store retailer of Private label Apparel) characteristics and product supply process of Korean casual apparel brands. The research was conducted by questionnaire surveys to 63 casual apparel brands. SPA characteristics of each brand were measured with four SPA characteristic indices: short product supply cycle, spacious retail floor, single brand retail store, and low product price compared to the quality of the product. The 63 apparel brands were grouped by SPA index score. The brands belonged to group H had high index score and brands in group L had low index score. The results of this study showed that the most of the casual apparel brands' products were sold at department stores, especially the brands belonged to group L greatly depended on department stores. Few apparel brands have spacious retail floor. The retail product price of the brands belonged to group H was low price while the product price of the brands belonged to group L was in the medium-high price. The supply time of the new products was short in general. The most brands supplied new styles to the retail floor within 1 to 3 weeks. The information technology was heavily used. The brands belonged to group H highly used information technology including bar codes system, pas data analysis, and inventory control system. The current style trends were analyzed with street fashion and feedback from the shop managers.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.275-286
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• 2015

In this paper, we propose a practical method for setting up a daily production plan which can operate semiconductor fabrication factories more stably and linearly by determining work in process (WIP) targets and movement targets. We first adjust cycle times of the operations to satisfy the monthly production plan. Second, work in process (WIP) targets are determined to control the production progress of operations: earliness and tardiness. Third, movement targets are determined to reduce cumulated differences between WIP targets and actual WIPs. Finally, the determined movement targets are modified through a simulation model which considers capacities of the equipments and allocations of the WIPs in the fab. The proposed daily production planning method can be easily adapted to the memory semiconductor fabs because the method is very simple and has straightforward logics. Although the proposed method is simple and straightforward, the power of the method is very strong. Results from the shop floor in past few periods showed that the proposed methodology gives a good performance with respect to the productivity, workload balance, and machine utilization. We can expect that the proposed daily production planning method will be used as a useful tool for operating semiconductor fabrication factories more efficiently and effectively.