• 서비스연구
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• 제11권1호
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• pp.45-58
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• 2021

요구공학은 대형화 및 분산화 되고 있는 정보시스템의 개발환경 속에서 시간적·공간적 제약 없이 정확하고 명확한 요구사항을 추출, 분석, 명세, 관리, 실증검증 등의 다양한 프로세스와 활동들로 진행한다고 볼 수 있다. 따라서, 프로젝트의 성공을 위해 이해관계자들 간의 협력과 체계적인 요구공학이 무엇보다 중요하다. 요구사항을 잘 개발하고 지속적인 평가 및 관리를 하는 것이 프로젝트관리에 있어서 성공하는 지름길이라 할 수 있으며, 정보시스템 감리 수행에서도 요구사항과 관련하여 매우 중요한 사항으로 인식되고 있다. 정보시스템 감리 수행과 감리 대상이 되는 사업 수행시 요구공학 측면의 개선이 필요하다. 이에 본 연구는 현행 감리 수행시 감리점검해설서와 감리점검가이드를 참조하여 대상 사업에 적합한 점검항목을 도출하고 감리 점검사항인 점검항목의 도출 근거가 되는 사업유형별 점검가이드 내용 중 요구공학적 측면에서 관련 점검항목들에 해당하는 프로젝트관리 및 품질보증 사업유형에 대한 감리시점/감리영역별로 점검항목들을 도출하였다. 도출된 점거항목에 대해 전문가의 설문 조사를 통해 적합성을 검증하였다.

• Management Science and Financial Engineering
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• 제16권1호
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• pp.119-135
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• 2010

In this paper, we readdress the optimization problem for minimizing the inspection cost in a back-light unit inspection system, which forms a network including a K-stage inspection system, a source inspection shop, and a re-inspection shop. In order to formulate our objective function when the system is in a steady state, assuming that the number of nonconforming items in a lot follows a binomial distribution when a lot is formed for inspection, we make a steady-state network flow analysis between shops, and derive the steady-state amount of flows between nodes and the steady-state fraction defectives by solving a nonlinear balance equation. Finally we provide some fundamental properties and an enumeration method for determining an optimal value of K which minimizes our objective function. In addition, we compare our results numerically with previous ones.

• 품질경영학회지
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• 제35권4호
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• pp.147-158
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• 2007

Owing to the rapid growth in automated manufacturing systems, screening inspection becomes an attractive practice for removing nonconforming items, and it has been suggested that inspection will essentially become an inherent part of modem manufacturing processes. In this paper, we propose rectifying screening inspections which allow quality practitioners to use performance and surrogate variables interchangeably in real-time applications. Two screening inspections are considered; a statistically-based screening inspection to reduce the current proportion of nonconforming items to a specified AOQ(average outgoing quality) after screening, and an economically-based screening inspection where the tolerance limit is determined so that the expected total cost is minimized. It is assumed that the performance variable and the surrogate variable are jointly normally distributed. For two screening inspections, methods of finding the optimal solutions are presented and numerical examples are also given.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.287-289
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• 2012

The building construction industry of Korea was going through difficulties in improving productivity and competitiveness in international market. Therefore we expected to see the improvement in productivity by applying six-sigma based approach to general reinforced concrete construction work. As a result of applying DMAIC method, one of 6 sigma tools, we found that the most effective inspection items are 'Gap of forms' and 'status of clean'. We could see from this case study that the percentage of additional work days has decreased to 37.7% as a result of applying six-sigma based approach to reinforced concrete construction.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2007년도 추계학술대회 및 정기총회
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• pp.418-421
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• 2007

For Shock obsorber piston led is launched to the market through luring, milling, grooving, rolling, inspection and finally packing processes, To this time around 11 items, that is, out diameter and length etc..for the piston lod are inspected strictly as a total inspection. Piston Lod is being produced 30,000 a day and its excessively repeating inspection is getting induce repetition strain injury and reduce production rate as fatigue accumulation of worker increase inspection errors. Therefore, for the inspection process is severely needed a progressive improvement through the automation. In this study, we consider automation method of piston led inspection process and suggest an efficient automation strategy as improving the various problems in present manual inspection way.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1642-1649
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• 2010

At present, KORAIL is in the middle of renovating. All steps exert great effort at cost reduction and a profit improvement. Especially to improve maintenance method and inspection period at the rolling-stock division lots of research is under progress. Daily inspection of rolling stocks is to operate the rolling stock normally. Daily inspection items are driving control device, coupling device, brake system, water system and air conditioning system, electrical system etc. Half of the maintenance manpower are inputted at daily inspection. Strengthens the quality and optimize the proportion of daily inspection are urgent problem. Daily inspection period extension aim is as follows. KTX from 3,500km to 5,000km, passenger car from 1st to 3,500km, new style electric locomotive from 2nd to 5,000km, the diesel locomotive is 2,800km from 1,200km. In this paper, the optimal daily inspection period and methods are considered including expected problem and counter measures.

• 한국건설관리학회논문집
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• 제20권2호
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• pp.13-27
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• 2019

가설공사는 임시시설물이지만 공사기간동안 사용빈도가 높으며 공사비의 10% 내외를 차지하고 있어 체계적인 관리가 필요하다. 하지만 가설공사의 시공검측정보들은 설계도서 및 시방사항에 특별한 명시가 없는 경우가 많으며 제기준에 대한 사항도 방대하다. 이로 인해 가설공사에 대하여 품질점검을 실시할 경우 관련 점검업무들을 비효율적으로 수행하며, 인간적인 오류가 발생할 확률이 높다. 따라서 본 연구에서는 가설공사에 대하여 품질점검 업무수행을 지원하고 관련 정보를 제공할 수 있는 전자작업지원시스템을 적용하고자 한다. 이를 위해 IDEF0를 활용하여 업무 단위프로세스별 정보흐름을 규명하고 EPSS기반 품질점검 업무체계를 정리하여 프로토타입을 개발한다. 이후 현장적용을 통한 검증방법으로 가설공사 품질점검 업무의 효율과 정보접근성을 향상하고자 한다.

• 대한산업공학회지
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• 제19권3호
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• pp.25-35
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• 1993

Economic screening procedures using a correlated variable are proposed to assure that the proportion of conforming items is above a desired level after screening. It is assumed that the performance variable and the screening variable are jointly normally distributed. Two screening procedures are considered. In the first screening procedure, all of the items are inspected on the screening variable. If an item fails to meet the screening specifications, it is rejected and excluded from shipment without inspection of the performance variable. In the second screening procedure, the item which fails to meet the screening specifications is inspected on the performance variable. If the value of the performance variable is within specifications the item is accepted, and the item is rejected otherwise. Cost models are constructed which involve cast from an accepted nonconforming item, cost from a rejected item, and quality inspection cost. Methods of finding optimal cutoff value on a screening variable are presented and numerical examples are given.

• 품질경영학회지
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• 제23권3호
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• pp.20-32
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• 1995

This paper is concerned with the economic selection of both the lower limit and the process mean for a continuous production process. Consider a production process where items are produced continuously. All of the items are subject to acceptance inspection. The items for which the measured values of the quality characteristic are larger than the lower limit are accepted, and those smaller than the lower limit are rejected and excluded from shipment. The process mean may be set higher to reduce the costs incurred by imperfect quality. Using a higher process mean, however, results in a higher production cost when production cost is an increasing function of the quality characteristic. Assuming that the quality characteristic is normally distributed with known variability, cost models are constructed which involve production cost, cost incurred by imperfect quality, rejection cost, and inspection cost. Methods of finding optimal values of the lower limit and the process mean are presented and numerical examples are given.

• Management Science and Financial Engineering
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• 제13권2호
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• pp.141-157
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• 2007

In this paper, we address a design problem and a case study of a K-stage back-light-unit(BLU) inspection system, which is composed of K stages, each of which includes an inspection process and a rework process. Assuming the type I, II errors and the inspection-free policy for items classified as good, we determine the smallest integer of K which can achieve a given target defective rate. If K does not exist, holding the current values of the type I, II errors, we search reversely the defective rate of an assembly line and the defective rate of a rework process, to meet the target defective rate. Our formulae and methodology based on a K-stage inspection system could be applied and extended to similar situations with slight modification.