• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2011년도 춘계학술대회
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• pp.731-746
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• 2011

The successful and sustainable growth of SMEs depends on their ability of strengthen their competitiveness in quality and cost and service more than anything else as a fundamental of operation. Among these key competitive factors of SMEs, quality is the most critical factor in manufacturing business fields. Because quality strongly influence cost and service performance on this manufacturing business field. There are many different ways to improve the quality performance but it needs proper management decision to choose the best way what can maximize outputs with minimum inputs. And it needs effective measurement methods and some indicators to analysis the quality performance properly. The quality cost is one of the simplest key indicators to measure the quality performance and the effectiveness of quality related management decisions. The major purpose of this study is to diagnose the categorized current level of actual quality cost of local SMEs to maximize their quality management effectiveness through comparing their level with others what's expressed in early studies. In this study, through survey on local SMEs, we found that their average annual quality cost ratio versus turnover - Total amount of annual quality cost divided by annual turnover - is around 3.69% excluded some SME's performances what have different quality control measures with others. And we found some results what corresponded with the early studies on the correlations between those categorized quality costs factors and some discrepancies between some of the literature model and the early case study results as follows. There were negative correlations between the Prevention costs and the External failure costs, and the Appraisal costs and the External failure costs, and there was positive correlation between the Appraisal costs and Internal failure costs same as early studies. But, we couldn't found any strong negative correlations between the Cost of control - Preventive costs & Appraisal costs - and the Cost of Failure of control - Internal & External failure costs -. It reveals not only the lack of effectiveness on their preventive or appraisal activities but also it can reveal there were so many effective ways to prevent the failure costs properly such as some innovative investment on Factory automation includes Error Proofing and more preventive actions to improve the effectiveness of the typical management methods likes CE (Concurrent Engineering), APQP (Advanced Product Quality Planning), FMEA (Failure Mode & Effect Analysis) etc.

• 품질경영학회지
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• 제15권1호
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• pp.2-12
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• 1987

Warranty cost usually involves complex factors paticularly when the product concerned consists of a great deal of parts. In spite of that it can be assessed by means of rather simple mathematical expression, it is possible to realistically appraise the sensitivity to any type of quality policy. This paper thus presents the mathematical concept related to the warranty cost and the general relationship showing that quality policy can be established in connection with the economic quality level.

• 품질경영학회지
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• 제4권1호
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• pp.13-19
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• 1976

In the quality planning phase, the techniques for measuring cost-quality trade-offs are used for the selection of the optimal design specifications when design flexibility permits significant trade-offs to be made. But the product quality is not only depends on the developing cost, but also the time for developing that product. Therefor it is important to seek a methodology for estimating time-cost-quality trade-offs associated with the quality planning projects. This paper is aimed to find a methodology of time-cost-quality trade-offs and to develop a proper algorithm.

• Journal of Construction Engineering and Project Management
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• 제4권3호
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• pp.53-59
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• 2014

Project managers are responsible to conduct project on time with least amount of costs and the most possible quality with respect to shortage of resources and environmental certainties. They have to make the best decision to reach such conflicting objects. In this study the project scheduling with multi goals-multi modes was planned in fuzzy conditions under resource constraints and expanded by fuzzy goal programing (FGP). The project cost was calculated by the price of renewable resources and the quality criteria were evaluated by the quality function deployment method (QFD). Finally the model was verified by a construction case study with 22 activities along with solving by GAMS. The results showed that this model could provide a systematic framework to facilitate the decision making process and made the project managers to be able to schedule the project closer to reality.

• Industrial Engineering and Management Systems
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• 제6권2호
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• pp.136-145
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• 2007

The selection of suppliers and the determination of order quantities to be placed with those suppliers are important decisions in a supply chain. In this research, a non-linear mixed integer programming model is presented to select suppliers and determine the order quantities. The model considers the purchasing cost which takes into account quantity discount, the cost of transportation, the fixed cost for establishing suppliers, the cost for holding inventory, and the cost of receiving poor quality parts. The capacity constraints for suppliers, quality and lead-time requirements for the parts are also taken into account in the model. Since the purchasing cost, which is a decreasing step function of order quantities, introduces discontinuities to the non-linear objective function, it is not easy to employ traditional optimization methods. Thus, a heuristic algorithm, called particle swarm optimization (PSO), is used to find the (near) optimal solution. However, PSO usually generates initial solutions randomly. To improve the PSO solution quality, a heuristic procedure is proposed to find an initial solution based on the average unit cost including transportation, purchasing, inventory, and poor quality part cost. The results show that PSO with the proposed initial solution heuristic provides better solutions than those with PSO algorithm only.

• 품질경영학회지
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• 제25권4호
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• pp.57-70
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• 1997

Consider a production system where all manufactured products are screened through automatic inspection equipment. The products for which the measured value of quality characteristic is larger than the lower screening specification limit (SL) and smaller than the u, pp.r screeing specification limit(SU) are accepted. Those smaller than SL are reworked and those larger than SU are excluded from the process. Assuming that the quality characteristic is normally distributed with known variance, this paper suggests cost models which involve inspection cost, production cost, rework cost, exclusion cost and quality cost, and presents the methods of finding the optimal values of the screening specification limits and the process target. Numerical example is given to demonstrate the a, pp.icability of the cost models suggested in this paper.

• Journal of Construction Engineering and Project Management
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• 제8권1호
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• pp.1-9
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• 2018

US transportation agencies are dealing with shrinking budgets, limited work forces, and deteriorating infrastructure. In order to cope with funding uncertainty, state highway agencies are now looking into their own organizations and identifying programs, practices, and processes that have potential for cost saving. A quality assurance (QA) program is an integral part of highway construction and ensures a project's contracted level of quality. The cost of quality (conforming and nonconforming) can constitute a sizable part of total construction cost. As the quality assurance programs evolved, various practices and processes were developed over time and later adopted by state highway agencies. These practices and processes include different QA standards and specifications, varying testing methods, central testing lab vs. on site testing, performance based vs. prescribed quality assurance practices, implementation of innovative quality assurance practices, etc. Therefore, there is an opportunity to assess different QA strategies and recommend those practices that are effective and cost efficient. A national survey was conducted by the authors, which provided a detailed mapping of various QA practices and processes used as part of QA programs and identified areas where agencies can focus on for cost savings. The survey found that QA sampling and testing plans, optimization of sampling plans, optimization of QA standards and specifications, and implementation of innovative test methods and processes are the main areas the agencies should focus to lean the current QA programs.

• 품질경영학회지
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• 제21권2호
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• pp.35-47
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• 1993

This study was performed to obtain the internal failure cost in the failure and rework using cost table. The manufacturing cost is different according to each production process. Thierefore, it is difficult to calculate of the manufacturing cost. Using the cost table internal failure cost can be calculated easily in each process.

• 대한안전경영과학회지
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• 제17권1호
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• pp.321-335
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• 2015

This study introduces the methods to apply and develop the integrated Cost of Quality (COQ) and Time-Driven Activity-Based Costing (TDABC) model for seeking not only quality improvement but also reduction of overhead cost. Inefficient and uneconomical COQ activities can be identified by using time driver which also maximizes the quality improvement for Prevention-Appraisal- Failure (PAF) quality costs. In contrast, reduction of the indirect cost of unused capacity resource using Quality Cost Capacity Ratio (QCCR) of TDABC minimizes overhead cost for COQ activities. In addition, linkage between Overall Equipment Effective (OEE) and Time Driver develops the integrated system of Total Productive Maintenance (TPM) and TDABC model. Lean OEE maximizes when an Unused Time (UT) of TDABC that are TPM losses and lean wastes reduces whereas the TPM Cost Capacity Ratio (TCCR) of TDABC minimizes indirect cost for non-value added TPM activities. Numerical examples are derived to better understand the proposed COQ/TDABC model and TPM/TDABC model from this paper. From the proposed model, process mapping and time driver of TDABC are known to lessen indirect cost from general ledger of comprehensive income statement with a better quality innovation and improvement of equipment.

• 품질경영학회지
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• 제26권1호
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• pp.172-191
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• 1998

In this paper, dimension tolerance design for components is studied. Three cost factors are considered: machining cost, rework cost, and loss related to product quality which is affected by the tolerances of components. We propose a procedure to determine the optimal tolerances of components and a, pp.y the procedure to design the tolerances of fine motion stage in semicoduct machine. We compare the proposed procedure with the existing model for determining tolerance economically.