• 한국컴퓨터정보학회논문지
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• 제27권12호
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• pp.277-284
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• 2022

본 논문은 조선소 소조립 공정의 스키드 컨베이어 환경에서 전체 작업 시간을 최소화하기 위해 스키드 처리 순서를 최적화하는 방법을 제안한다. 소조립 공정은 일련의 정해진 작업들로 구성되며 스키드의 종류에 따라 요구되는 작업 시간이 다르다. 전체 작업 시간을 결정짓는 스키드의 컨베이어 투입 순서는 적절하게 최적화되어야 하며 문제 크기는 스키드 개수에 따라 지수적으로 증가한다. 이러한 점에서 UniDev라 불리우는 새로운 방법을 제안하는데 동시간에 진행되는 작업 소요 시간의 차이에 관한 평균절대편차를 정의하고 이를 점진적으로 개선한다. 다양한 스키드 개수와 공정의 개수에 대한 시뮬레이션 결과 제안된 방법이 Multi-Start 방법과 2-OPT 방법보다 전체 작업 소요 시간을 효과적으로 줄일 수 있음을 확인하였다.

• 한국시뮬레이션학회논문지
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• 제19권1호
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• pp.73-82
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• 2010

전 세계 조선 산업에서 생산성의 향상이 크게 이슈화되면서, 생산 라인의 생산성 향상을 위해 새로운 방법론, 생산 자동화, 향상된 생산계획 및 일정계획 등의 연구가 진행되어 왔다. 본 연구는 조선 생산의 일정계획과 관련하여 소조립 라인의 소일정계획의 최적화를 통한 생산성 향상에 관한 것이다. 소조립 라인의 소일정계획 최적화를 위하여 공정 별 작업자 배치와 운용에 관한 시나리오와 스키드 패턴의 투입 순서를 미정 다항식 문제로 정식화하고 문제 해결하기 위해 메타휴리스틱 방법 중 하나이며 확률변수를 사용하는 시뮬레이티드 어닐링을 적용하여 지역 최소값에 빠지는 것을 막고 전역 최소값을 찾도록 하였다. 실제 조선소의 소조립 라인의 작업 시간 데이터와 스키드 투입 순서 데이터를 사용하여 최적화를 수행하고 최적화 결과의 효과를 검증하였다.

• 한국CDE학회논문집
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• 제10권3호
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• pp.210-216
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• 2005

Digital manufacturing could be very effective in shipbuilding in order to estimate the process time, to improve the operation efficiency, and to prevent bottleneck processes in advance. The subassembly process having done research consists of piece arrangement, tack welding, robot welding, manual welding and so on. The robot welding of them was the focus of the simulation. The analysis and modeling were carried out by using UML (Unified Modeling Language) as well as $IDEF\phi$ (Integration DEFinition). The characteristics of the process resources were analyzed using the shipyard data, and the layout of the subassembly line was designed with the resources. Using the constructed resource and process model, the productivity and efficiency of changed robot welding stage were investigated. It was simulated how much the variations in the resource performance have influence on improvement of productivity. One of the important outputs in this simulation was the cycle time during a certain period's work. The cycle time prediction was also undertaken for the different torch and the different piece arrangement. The proposed model was established three-dimensionally in a digital environment so that interferences among objects and space allocations for the resources could be easily investigated.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 춘계학술발표회요약집
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• pp.136-136
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• 1999

• 에너지공학
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• 제12권4호
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• pp.281-288
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• 2003

The MATRA-LMR code has been developed based on a subchannel analysis method for LMR (Liquid Metal Reactor) core subassembly thermal hydraulic design and analysis. The code was improved to allow a seven assembly calculation and can account for inter-assembly heat transfer based on a lumped parameter model. This paper describes the main modifications and improvements of the code and shows reference calculation results which compared single assembly calculation with seven assembly calculation cased for driver and blanket subassemblies of the KALIMER 150 MWe breakeven conceptual design core. KAL- IMER is a pool-type sodium cooled reactor with a thermal output of 392.0 MWth, which have inherently safe, environmentally friendly, proliferation-resistant and economically viable reactor concepts.

• 산업공학
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• 제12권4호
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• pp.586-594
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• 1999

This paper introduces a production scheduling system for the block assembly shop in a shipbuilding company. We are to make a schedule for the assembly shop and related subassembly production shop. The objectives of the scheduling system are balancing of the workload of the subassembly shops as well as the assembly shop. There are a number of technological and resource constraints including assembly space restriction which is most important and critical resource in the shop. It is very hard and time consuming to consider the two problems, the workload balancing and the spatial allocation problem, simultaneously, and hence, we analyze the two problems independently. The first problem has already been introduced(고시근, 1996), and the overall appearance of the system and the spatial allocation algorithm are presented in this paper.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.969-971
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• 2000

In this paper, shortening of product life cycle and wide disposal of consumer product have given rise to many environmental problems, it needs to propose module design principle for saving of disassembly cost and reusing of used part and subassembly. To analyze characteristics of module for recycling, materials and function of part and subassembly must be classified. In disassembly process, a unit operation can be grasped for disassembly function, worker, tool and sorting process. As a result of applying module design principle, simpler structure and reduced structural interference can be realized for product structure. For disassembly, simpler disassembly and quicker disassembly can be obtained for recycling.

• International Journal of CAD/CAM
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• 제6권1호
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• pp.19-27
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• 2006

To survive in the current shipbuilding industry it is of vital importance for shipyards to achieve an optimal utilization of resources, make an achievable planning and ensure that this planning is kept. Possible problems should be eliminated before production starts and if unexpected disturbances occur in the actual production the right measures should be taken. Due to the dynamic nature of the production process, the continuous variation in products and the complexity of both, all this can hardly be achieved with conventional static planning and analysis systems. Simulation provides a solution here, since this enables the modelling and evaluation of the dynamic relations between product and production process. After a global introduction to production simulation in general and the application of simulation at the Flensburger shipyard, this paper presents a tool that has been developed to simulate the various complex assembly processes taking place at shipyards. Subsequently the simulation model for the subassembly production at Flensburger, in which this tool is applied, will be discussed.

• 한국경영과학회지
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• 제17권1호
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• pp.55-65
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• 1992

There are takes performed on only one side (right side or left side) of the assembly line, and task groups in which the tasks are more related to one another like a subassembly. In the Assembly Line Balancing (ALB) of the large-sized product such as bus and truck, the side on which tasks are performed and the related task groups should be considered to improve work methods and to appropriately lay out parts and facilities in the line. In this paper, presented are the 0-1 programming formulations for the ALB with the constraints of assigning the same side tasks to the station. The objective of minimizing the number of stations is combined with the objective that the total number of the related task groups handled by all the stations is minimized. Also, proposed are the methods of reducing the number of variables and constraints, and of determining the station to which subassembly tasks are assigned.

• 한국정밀공학회지
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• 제16권5호통권98호
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• pp.29-39
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• 1999

Many industrial products can be assembled in various sequences of assembly operations. To save time and cost in assembly process and to increase the quality of products, it is very important to choose an optimal assembly sequence. In this paper, we propose a methodology that generates an optimal assembly sequence by using the knowledge of experts. First, a product is divided into several sub-assemblies. Next, the disassembly sequences of sub-assembly are generated using disassembly rules and special information can be extracted through the disassembly process. By combining every assembly sequence of sub-assemblies, we can generate all the possible assembly sequences of a product. Finally, the expert system evaluates all the possible assembly sequences and finds an optimal assembly sequence. It can be achieved under consideration of the parameters such as assembly operation, tool change, safety of part. basepart location, setup change, distance, and orientation. The developed system is applied to UBR(Unit Bath Room) example.