• 산업공학
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• 제16권3호
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• pp.352-361
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• 2003

Vehicle manufacturing plant is a typical mixed-model production system. Generally it consists of three main shops including body shop, painting shop and assembly shop in addition to engine shop. Each shop contains diverse manufacturing processes, all of which are integrated in a form of flow line. Due to the high pressure from the market requesting small-volume large variety production, production planning becomes very critical for the competitiveness of automotive industry. In order to save costs and production time, production planning system is requested to meet some designated requirements for each shop: to balance the work load in body and assembly shops, and to minimize the number of color changes in painting shop. In this context, we developed a sequencing module for a vehicle production planning system using the ILOG Solver Library. It is designed to take into account all the manufacturing constraints at a time with meeting hard constraints in body shop, minimizing the number of soft constraints violated in assembly shop, and minimizing the number of color changes in painting shop.

• 산업공학
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• 제18권2호
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• pp.136-147
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• 2005

This paper introduces a simulation study regarding the operation of the Painted Body Storage (PBS) in an automobile factory. In the paint shop of the factory, same colored bodies are grouped together in order to increase the effectiveness of process, for example decrease the loss of cleaning the painting-gun when the color of body changes from one to another. However the production of automobiles in the assembly shop is a typical example of the mixed model assembly production. Therefore PBS locates between the paint shop and the assembly shop for control the input sequence of bodies to the assembly shop, and it enables to meet the smoothing requirement of assembly sequence. There are highly restricted constraints on the assembly sequence in a assembly shop. Those are spacing restriction and smoothing restriction. If such restrictions are violated, conveyor-stop or utility work will be necessary. Thus the major objective of PBS is to control the assembly sequence in a way to meet the two restrictions. In this paper a case study of PBS in an automotive factory is introduced. The storage/retrieval algorithms are suggested and the proposed system is verified using simulation models. Sensitivity analysis for operating factors is also conducted.

• 한국자동차공학회논문집
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• 제11권6호
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• pp.118-126
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• 2003

Digital Manufacturing is a technology facilitating effective developments and agile productions of the product via digital computer models representing physical and logical schema and the behavior of the real manufacturing systems including manufacturing resources, environments and products. For the successful application of this technology, a digital factory as a well-designed and an integrated environment is essential. In this paper, we constructed the sophisticated digital factory of a Korean automotive company's body shop, and conducted precise simulations of unit cell, lines and the whole factory for the collision check, the production flow analysis and the off-line programming. We expect that this digital factory of the body shop helps us achieve great savings in time and cost for many manufacturing preparation activities of the new car development.

• Patent21
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• 통권73호
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• pp.18-24
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• 2007

• 산학경영연구
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• 제13권
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• pp.263-273
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• 2000

벤츠(현 다임-클라이슬러)자동차회사는 새로운 공장을 미국 앨라배마 주 Vance 지역에 건설하고 이곳 공장으로부터 스포츠-레저용의 4륜 구동 M-class 자동차를 생산하고 있다. 이 벤츠공장의 생산라인은 차체형성공정, 도장공정, 그리고 엔진조립 공정으로 나누어져 있고 이들 생산라인사이에는 한 라인에서의 고장(down)이 다른 라인에 파급되지 않도록 완충라인(Buffer)이 설치되어 있다. 본 연구의 목적은 일정한 비율의 고장률을 각 생산라인에 적용시켰을 때 주어진 생산목표(270대)를 달성할 수 있는지, 만약 달성할 수 없다면 가장 문제가 되는 생산라인은 어디인지, 또 생산라인 사이에 존재하는 완충라인이 어느 정도의 완충역할을 하는지, 최적의 생산능력을 유지하기 위한 완충라인의 크기는 어느 정도인지 등, 각종 생산라인의 운영지침(operation policy)들을 시뮬레이션 기법을 이용하여 탐색한 후 병목생산시설(bottleneck)을 찾아내는 것이다. 본 연구를 위한 시뮬레이션 도구로는 ARENA를 이용했고 20일 간의 시뮬레이션 결과를 종합하여 분석하였다. 또 신뢰구간 95% 범위에서 각 생산라인의 최대 생산능력도 측정하여 실제 생산대수와의 차이를 규명할 수 있는 근거를 제공하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1166-1172
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• 2003

The extremely strong competition among the world automobile industries has introduced the concept of PLM in the total production activities, one of whose major components is VM(Virtual Manufacturing). If the production lines are equipped with robots, the application of OLP in the virtual space is fully mature. However, in the point of the investment's and the maintenance's view, there are always some activities, which can not be automated: for example, typically the manual welding for prefixing in the automobile body shop and the material loading. Process planning for these activities, therefore, are decided mainly by experiences, which caused many repeated rework of the processes and the inconvenience of the workers, and resulted consequently in the reduction of the productivity and the safety of the workers. In this paper, the optimal dimension of the welding gun and its handle position and the optimal working path is simulated and decided by use of DELIMN/IGRIP and DELMIA/Ergo and the working area modelized in the virtual workcell of DELMIA.

• Journal of Welding and Joining
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• 제34권1호
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• pp.21-25
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• 2016

The automotive vehicle is made through the following processes such as press shop, welding shop, paint shop, and general assembly. Among them, the most important process to determine the quality of the car body is the welding process. Generally, more than 400 pressed panels are welded to make BIW (Body In White) by using the RSW (Resistance Spot Welding) and GMAW (Gas Metal Arc Welding). Recently, as the needs of light-weight material due to the $CO_2$ emission issue and fuel efficiency, new joining technologies for aluminum, CFRP (Carbon Fiber Reinforced Plastic) and etc. are needed. Aluminum parts are assembled by the spot welding, clinching, and SPR (Self Piercing Rivet) and friction stir welding process. Structural adhesive boning is another main joining method for light-weight materials. For example, one piece aluminum shock absorber housing part is made by die casting process and is assembled with conventional steel part by SPR and adhesive bond. Another way to reduce the amount of the car body weight is to use AHSS (Advanced High Strength Steel) panel including hot stamping boron alloyed steel. As the new materials are introduced to car body joining, productivity and quality have become more critical. Productivity improvement technology and adaptive welding control are essential technology for the future manufacturing environment.

• 한국멀티미디어학회논문지
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• 제15권7호
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• pp.941-950
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• 2012

본 연구에서는 PC상에서 인체 3차원 데이터에 상하의 의류를 중첩 착의하는 가상 착의 시스템을 소개한다. 이를 위하여, 레이저 스캔 방식으로 얻은 인체 3차원 데이터와 의류 앞뒷면의 모습을 촬영하여 얻은 의류 디지털 데이터를 이용한다. 2차원의 앞뒷면 의류 디지털 데이터에는 의류 소재 내 질점 간의 장력이 반영되었고, 인체 데이터에의 착의 과정에는 마찰력과 중력을 적용해 주었다. 하의 착용 시에는 마찰력과 중력에 추가적으로 혁대 개념을 도입하여 흘러내리는 의류를 고정하였고, 하의를 착의한 인체데이터위에 상의를 착의하는 중첩 착의 방법을 제시하였다. 본 시스템이 지닌 장점은 복잡한 패턴을 이용하여 착의하는 다른 연구와 달리, 의류의 앞뒷면만을 이용하여 착의하면서도 현실감은 뒤지지 않는다는 것에 있다. 현재 의류전자상거래 시 의류의 앞뒷면만을 전시하여 판매하는 방법과 유사한 방식으로 온라인 판매가 이루어지나, 착의 모습을 제공할 수 없는 기존 방식과 달리 3차원의 착의 모습까지 제공하게 되어, 의류 판매의 방식을 바꾸게 할 것으로 기대한다.

• 대한산업공학회지
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• 제41권5호
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• pp.470-480
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• 2015

There are many challenges in manufacturing system for new factory construction. Although factories produce same product, the layout of each factory may be different. The body shop in an automotive factory is a typical flow line with assembly, but the layout concept of the line varies among factories. In this paper, two types of layouts in the body shops of automotive factories, one for layered build and the other for modular build, are compared using simulation study. The simulation experiments indicate that the modular build layout is better than the layered build layout with respect to production rate. The effects of various failure distributions on the throughputs are also investigated, and some insights are suggested regarding the layout concept.

• 산업공학
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• 제14권2호
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• pp.127-133
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• 2001

Virtual Manufacturing is a technology facilitating effective development and agile production of products via computer models representing physical and logical schema and the behavior of the real manufacturing systems. For the successful application of this technology, a virtual plant as a well-designed and integrated environment is essential. We propose a series of systematic approaches and effective methods for construction and operation of a virtual plant in this paper, such as a 3-D CAD modeling, cell and line simulations and databases. We developed key technologies for measuring and 3-D CAD modeling of many equipments, facilities and structures of the buildings. In order to study the benefit of virtual manufacturing, we constructed a sophisticated virtual plant model of a Korean automotive company's body shop, and conducted precise simulations of unit cell, lines and the whole plant. We could obtain the benefit of savings in time and cost in many manufacturing preparation activities in the new car development processes.