• 한국경영과학회지
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• 제22권1호
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• pp.25-49
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• 1997

Printed circuit board (PCB) assembly line configuration is characterized by very long set-up times and high work in process (WIP) inventory level. The scheduling method can significantly reduce the set-up times and WIP inventory level. Greedy sequence dependent scheduling (GSDS) method is proposed based on the current methods. The proposed method is compared with the current method in terms of three performance measures: line throughput, average WIP inventory level, and implementation complexity.

• 산업경영시스템학회지
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• 제12권19호
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• pp.79-88
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• 1989

This characteristics of process industries are high capital intensity, relatively long and sequence dependent setup times, and extremely limited capacity resources. The lot sizing, sequencing and limited capacity resources factors must he considered for production scheduling in these industries. This paper presents a mixed integer programming model for production scheduling. The economic trade offs between capacitated lot sizing flow shop scheduling and sequence dependent setup times also be compared with SMITH-DANIELS's model. As a results, it is shown that this paper has lower total cost, more efficient throughput than SMITH-DANIELS's model.

• Journal of Information Science Theory and Practice
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• 제1권2호
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• pp.6-15
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• 2013

Dr. Ranganathan's "Principles for Helpful Sequence" among the set of normative principles play an exclusive role in the arrangement of subject isolates. Each subject in the universe of subjects is regulated by a guiding principle of its own which analogously determines the sequence of Arrays in ordering the subject surrogates or isolates. For example, the "Principle of Later-in-Evolution" is applied for sequencing isolates of Animal and Plant Species; this concept can be applied to one of the tools of KOS viz. Taxonomies. The application of Principles for Helpful Sequence is summarily presented and in the process the paper highlights the inherent elements of knowledge organization in each one of these principles in a manner that might map the future course of research in this area with the potentiality to bring about a relation between principles for helpful sequence and KOS.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권4호
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• pp.450-457
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• 2018

The determination of assembly sequence in general mechanical assemblies plays an important role in terms of manufacturing cost, duration and quality. In the production of ships and offshore plants, the consideration of productivity factors and welding deformation is crucial in determining the optimal assembly sequence. In shipbuilding and offshore industries, most assembly sequence planning has been done according to engineers' decisions based on extensive experience. This may result in error-prone planning and sub-optimal sequence, especially when dealing with unfamiliar block assemblies composed of dozens of parts. This paper presents an assembly sequence planning method for block assemblies. The proposed method basically considers geometric characteristics of blocks to determine feasible assembly sequences, as well as assembly process and productivity factors. Then the assembly sequence with minimal welding deformation is selected based on simplified welding distortion analysis. The method is validated using an asymmetric assembly model and the results indicate that it is capable of generating an optimal assembly sequence.

• 한국시뮬레이션학회논문지
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• 제26권1호
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• pp.69-75
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• 2017

MCP(Multi-chip Package)는 두 개 이상의 Chip을 적층하여 하나의 패키지로 합친 제품이다. MCP를 만들기 위해서는 두 개 이상의 Chip이 동일한 Substrate에 적층되기 때문에 다수의 조립 공정이 필요하다. Package 공정에서는 Lot들이 동일한 특성을 가지는 Chip으로 구성되고 MCP를 구성하는 Chip의 특성은 Layer sequence에 의해 결정된다. MCP 생산 공정에서 WIP Balance 뿐만 아니라 Throughput을 달성하기 위해서는 Chip의 Layer sequence가 중요하다. 본 논문에서는 Chip들의 Layer sequence의 제약 조건을 고려한 스케쥴링 방법론을 제안한다.

• 한국정밀공학회지
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• 제5권3호
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• pp.31-42
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• 1988

This paper describes a computer aided process planning system called "Deep-Drawing", "Deep-Drawing" is designed for the drawing sequence of cylindrical and rectangular cups with or without taper and flange. The computer program has written in BASIC language with personal computer. Design Rules for process planning are formulated from process limitation, plasticity theory and experimental results including the know-how of many manufacturing factories. "Deep-Drawing" Capabilities include the analysis of drawing sequence by the determination of optimal drawing ratio, the determination of intermediate shape, dimensions, punch and die radius etc., the calculation of drawing loads and blank holder force to perform each drawing step, and the graphic outputs for the operation sheet.tputs for the operation sheet.

• Management Science and Financial Engineering
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• 제11권2호
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• pp.45-60
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• 2005

This paper investigates the application of the computer method COMSOAL (Computer Method of Sequencing Operations for Assembly Lines) to the process routing (PR) problem with multiple objectives. In any computer aided process planning (CAPP) system, one of the most critical activities for manufacturing a part could be to generate the sequence that optimizes production time, production cost, machine utilization or with multiple these criteria. The COMSOAL has been adopted to find the optimum sequence of operations that optimizes two major conflicting criteria : production cost and production quality. The COMSOAL is here slightly modified to simultaneously generate and evaluate a set of possible solutions (called as population) instead of processing a solution stepwise in each iteration. The significant features of the COMSOAL include : no parameters settings needed, and a guarantee of feasible solutions. Experimental results show that COMSOAL is a simple but powerful method to quickly generate multiple feasible solutions which are as good as the ones obtained from several other well-known process routing algorithms.

• International Journal of Reliability and Applications
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• 제12권1호
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• pp.49-60
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• 2011

The geometric process (GP) has been widely used for modeling failure and repair time sequences of repairable systems. The GP is mathematically tractable but restrictive in reliability applications since it actually assumes that the mean function of inter-failure times sequence asymptotically decreases to zero; and the mean function of successive repair times sequence asymptotically increases to infinity. This is generally unrealistic from an engineering perspective. This paper presents three extended GP models for modeling reliability deterioration and improvement (or growth) process. The extensions maintain the advantage of mathematical tractability of GP model. Their usefulness and appropriateness are illustrated with three real-world examples.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.236-239
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• 2009

Cowl cross bar, a component of automotive cockpit module, has been manufactured by using welding processes of several tube parts with different diameters. However, in order to reduce costs and increase the quality, it is required to develop a new production method to manufacture the cowl cross bar as one-piece In this study, therefore, eliminating the welding process, tube drawing process which is one of metal forming processes was designed by using combined drawing technique. In addition, the selectable range of area reduction ratio was defined as a design guideline and the designed process sequence was verified by finite element analysis.

• 음성과학
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• 제8권4호
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• pp.185-191
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• 2001

This study was designed to determine what components of spoken language have been relatively neglected in the teaching of listening comprehension in Korea and to suggest a model of listening process. Two types of tests were undertaken using spoken and written forms of English with secondary school teachers of English and college students. Findings: Hearing power has been generally neglected in the teaching of listening comprehension. Hearing power which can be thought as an active process is defined as an ability to transfer the sequence of discrete phonetic segments without word boundary into the sequence of words in phonemic representations by using both nonlinguistic factors and linguistic factors including perception rules based on phonetics and phonology. Vocabularies, hearing-speaking power, syntactic structures and idiomatic expressions are to be taught for spoken English. A model of listening process was suggested and discussed.