• Management Science and Financial Engineering
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• 제1권1호
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• pp.67-90
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• 1995

In planning an assembly system, choosing the proper assembly sequence is one of the most important decisions because it significantly affects the costs associated with the assembly process. This paper deals with the selection of assembly sequences in flexible assembly systems. The selection criterion is the minimization of makespan to complete all assembly products. This problem is formulated as a "modified FAS scheduling problem" (MFASSP) and its scheduling procedure is described. The experimental results show that the procedure is very efficient for both quality of solution and computation time.

• Management Science and Financial Engineering
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• 제13권1호
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• pp.25-34
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• 2007

This paper is concerned with proving a conjecture that the two stage assembly system is reversible in deterministic makespan scheduling context. The reversibility means that a job sequence in the assembly system has the same makespan as that of its reverse sequence in the disassembly system which is the reversal of the assembly system. The proposed conjecture shows that the reversibility of serial flowshops can be extended to non-serial and synchronized shops.

• Genomics & Informatics
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• 제7권1호
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• pp.46-48
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• 2009

Finishing is the most time-consuming step in sequencing, and many genome projects are left unfinished due to complex repeat regions. Here, we have developed BACContigEditor, a prototype shotgun sequence finishing tool. It is essentially an editor that visualizes assemblies of shotgun sequence fragment reads as gapped multiple alignments. The program offers some flexibility that is needed to rapidly resolve complex regions within a working session. The sole purpose of the release is to promote collaborative creation of extensible software for fragment assembly editors, foster collaborative development, and reduce barriers to initial tool development effort. We describe our software architecture and identify current challenges. The program is available under an Open Source license.

• 전자공학회논문지SC
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• 제47권1호
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• pp.35-41
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• 2010

제품완성업체에서 생산성과 양품률을 향상시키기 위해서는 조립라인에서 필요로 하는 부품이 순서에 맞게 적시에 공급되어져야 하며, 이종부품의 공급으로 인한 조립라인을 멈추는 시간이 없어야 한다. 본 논문에서는 기존 바코드 기반 부품공급 시스템에서 이종부품 확인 및 서열 작업시 발생하는 수작업에 의한 불필요하게 소모되는 시간과 재사용이 불가능한 바코드 라벨 및 서열지로 인한 소모성 비용을 제거하고, RFID 기반의 부품공급 시스템이 가진 태그의 거리에 따른 인식률 저하로 인한 전송거리제한으로 발생하는 실시간 이종부품 확인 및 부품서열 관리의 어려움을 극복하는 방법으로 RFID와 USN이 융합된 형태인 스마트 파렛트기반의 직서열 부품공급 시스템을 제안하고, 간단한 구현을 통해 실현성을 입증하고자 한다.

• 경영과학
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• 제13권1호
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• pp.13-27
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• 1996

This paper considers the sequencing problem in mixed model assembly lines with hybrid workstation types and sequence-dependent setup times. Computation time is often a critical factor in choosing a method of determining the sequence. We develop a mathematical formulation of the problem to minimize the overall length of a line, and present a tabu search technique which can provide a near optimal solution in real time. The proposed technique is compared with a genetic algorithm and a branch-and-bound method. Experimental results are reported to demonstrate the efficiency of the technique.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.175-178
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• 2000

BOM has been widely used to manufacturing, product design and scheduling. There are several bug differences between Manufacturing BOM and Engineering BOM, which cause a lot of problems. A study to integrate both manufacturing BOM and Engineering BOM is researching to solve those problems. This thesis presents a extended Engineering BOM concepts considering assembly sequence model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2450-2452
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• 2003

We present a method to increase the productivity of multihead-gantry chip mounters for PCB assembly lines. To minimize the assembly time, we generate the mount sequence using the genetic algorithm. The chromosome, fitness function, and operators are newly defined to apply the algorithm. Simulation results are presented to verified the usefulness of the method.

• 한국공작기계학회논문집
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• 제15권1호
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• pp.70-75
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• 2006

This paper represents a study on disassembly sequence generation system for automobile parts. This system is practically very useful because proper disassembly sequence of end-of-life product becomes crucial as take-back obligations are imposed for environmental reasons. Therefore a disassembly sequence generation system is suggested to automatically derive all the feasible disassembly sequences from the assembly modeling files. As a result, in consideration of the all parts and subassemblies the optimum disassembly sequence is generated. And the optimum disassembly sequence for a certain part or subassembly can be also suggested.

• 제어로봇시스템학회논문지
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• 제6권6호
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• pp.506-513
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• 2000

This paper proposes a path planning algorithm for dispensers to increase the productivity in printed circuit board assembly lines. We analyze the assembly sequence of the dispenser, and formulate it as an integer programming problem. The mathematical formulation can accomodate multiple heads and different types of heads through extended cost matrix. The TSP algorithms are then applied to the formulated problem to find the near-optimal solution. Simulation results are presented to verify the usefulness of the proposed scheme.

• International Journal of Control, Automation, and Systems
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• 제5권2호
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• pp.192-199
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• 2007

This paper proposes a new printed circuit board (PCB) assembly planning method for multi-head surface mounters. We present an integer programming formulation for the optimization problem, and propose a heuristic method to solve the large NP-complete problem within a reasonable time. A dynamic programming technique is then applied to the feeder arrangement optimization and placement sequence optimization to reduce the overall assembly time. Comparative simulation results are finally presented to verify the usefulness of the proposed method.