• 산업경영시스템학회지
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• 제24권63호
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• pp.65-77
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• 2001

A more technical perspective is needed in estimating the effect of the Manufacturing Process for improving the Productivity, there are many statistical evaluation methods, convenience sampling, frequencies, histogram, QC seven tools, control chart etc. It is more important for the companies to use six sigma to reduce defective and improve the process control than the technical definition as a disciplined quantitative approach for improvement of process control and a new way of quality innovation. Process network analysis is a technique which has the potentiality for a wide use to improve the manufacturing process which other techniques can't be used to analyze effectively. It has some problems to analyze the process with feedback loops. The branch probabilities during quality inspections depend upon the number of times the product has been rejected. This paper presents how to improve the manufacturing process by statistical process control using branch probabilities, Moment Generating Function(MGF) and Sensitivity Equation.

• 품질경영학회지
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• 제35권2호
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• pp.1-26
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• 2007

The purpose of this research is to suggest the promotive directions of Quality Circle activity. Since 1975, variety of organizations in Korea have widely the implemented Quality Circle activities for their management systems. Today, Companies are facing the harsh realities of a competitive environment. This is no time for revolutionary change. Instead, Companies are instituting revolutionary change meant to have impact within a very short time frame. The Worker's Quality Circle activity is, essentially, a trouble shooting oriented voluntary small group within their working place to improve the surroundings creatively. The industries have enthusiastically used Quality Circle activities and were influenced from them. The Quality Circle activities can be regarded as a kind of Knowledge Management where new knowledge is created and knowledge is shared in the economy. However, the academics were less interested in this subject, as a result, there were no systematic guidances for Quality Circle activities. Also, the government was less interested in these activities, as a result, there were no systematic policy making for Quality Circle activities. Thus, in this research, the promotive directions for Quality Circle activities were suggested which were based on the results of survey Questionnaires presented to promoters of the domestic companies. As a results of this research, to maximize the effect of TQM(Total Quality Management) in the nationwide, Quality Circle activity as a bottom-up management should be more expanded and revitalized.

• 품질경영학회지
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• 제45권3호
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• pp.561-582
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• 2017

Purpose: The purpose of this study is to share the right conception of win-win partnership innovative activity. This study suggests the desirable methodology to Win-win Partnership. Also, through the in-depth analyzing of the existing problems, we intend to exclude such a formal and erroneous direction of the research. Methods: This study systematically analyzes the best cases of the win-win partnership focusing on the proceedings of the companies participating in the field of win-win Partnership at the national quality-circle contest. Results: This study reveals the underlying problems of win-win partnership innovative activity and draws the conclusion in the way of improvement about the win-win partnership innovative activity. This study also suggests the efficient method of the function and improvement of a system for activating win-win partnership innovative activity. Conclusion: Promoting the effective way of boosting win-win partnership innovative activity, we seek to improve the quality of the product among the companies, and let the a rising curve of the mutual growth continue among the companies by strengthening the competitiveness.

• Radiation Oncology Journal
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• 제18권4호
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• pp.337-344
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• 2000

목적 : 가상 시뮬레이션 기능을 갖는 CT 시뮬레이터의 기하학적인 성능평가를 위한 팬톰을 고안하여 제작하고, 그 팬톰의 성능을 보고하고자 한다. 대상 및 방법: .팬톰은 PMMA 재질로 직경 20 cm, 길이 24 cm인 원통과 25$\times25\times$31 cm$^{3}$인 직육면체가 합쳐진 모양으로 고안하였다. 원통의 겉표면에는 영상결손이 극소화되면서 CT 상에서 잘 구별이 되는 직경이 0.8 mm인 선을 4개의 나선모양으로 부착하였다. 직육면체는 4개의 24$\times24\times$0.5 cm3인 정사각형의 판으로 구성되어 있으며, 각판 위에는 24$\times$24 cm$^{2}$, 12$\times$12 cm$^{2}$, 6$\times$6 cm$^{2}$의 사각형 모양을 갖도록 선을 붙였다. 각각의 정사각형은 원통방향에 대해 0$^{\circ}$ , 15$^{\circ}$ , 30$^{\circ}$가 되도록 배치하였다. 직육면체의 부분에서는 조사면 및 치료 테이블의 각도, 콜리메이터 각도, 동중심점의 이동, SSD를 측정을 할 수 있으며, 원통형 부분에서는 갠트리 각도의 정확성을 평가하도록 고안하였다. 가상 시뮬레이션 소프트웨어를 통해 다양한 조건의 가상적인 시뮬레이션을 수행하였으며 가상 시뮬레이션의 결과를 이용하여 CT 시뮬레이터의 기하학적인 QC/QA를 수행하였다 결과 : 팬톰의 한 부분인 직육면체 스캔을 통해 얻은 DRR에서 구현된 각 24 cm 조사면의 크기에서 1 mm 이내의차이, 동중심점 이동에서는 0.5$\~$1 mm 차이가 있었음을 알 수 있었다. 콜리메이터 회전과 치료대 회전에서는 각각 0.5$\~$l$^{\circ}$ 의 차이가 있었고, 갠트리 회전에 있어서는 0.5$\~$1$^{\circ}$ 오차가 있었다. 슬라이스 간격이 10 mm 조건이 2$\~$5 mm 조건보다 영상구분의 어려운 점은 있었으나 결과는 유의할만한 차이가 없었다. 결론 : 자체 제작한 팬톰을 가지고 가상적인 모의 시뮬레이션을 했을 때 최대 2 mm와 1$^{\circ}$ 이내의 오차가 있었고 또한 스캔의 조건에 따라 오차가 변할 수 있다는 것을 알 수 있었다. 시뮬레이터에서 DRR을 구현했을 때 각각의 치료 조건들에 대해 오차가 임상적용 범위 안에 있어서 이 팬톰을 이용하여 주기적인 QC/QA에 사용할 수 있음을 보였다.

• 대한방사선치료학회지
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• 제11권1호
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• pp.16-21
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• 1999

Purpose : The aim of this study is to conform the possibility of the liquid type EPID as a QC tools to clinical indication and of replacement of the film dosimetry. Aditional aim is to describe a procedure for the use of a EPID as a physics calibration tool in the measurements of radiation beam parameters which are typically carried out with film. Method & Materials : In this study we used the Clinac 2100c/d with EPID. This system contains 65536 liquid-filled ion chambers arranged in a $256{\times}256$ matrix and the imaging area is $32.5{\times}32.5cm$ with liquid layer thickness of 1mm. The EPID was tested for different field sizes under typical clinical conditions and pixel values were calibrated against dose by producing images using various thickness of lead attenuators(lead step wedge) using 6 & 10MV x-ray. We placed various thickness of lead on the table of linear accelerator and set the portal vision an SDD of 100cm. To acquire portal image we change the field size and energy, and we recorded the average pixel value in a $3{\times}3$ pixel region of interest(ROI) at field center was recorded. The pixel values were also measured for different field sizes in order to evaluate the dependence of pixel value on x-ray energy spectrum and various scatter components. Result : The EPID, as a whole, was useful as a QA tool and dosimetry device. In mechanical check, cross-hair centering was well matched and the error was less than ?2mm and light/radiation field coincidence was less than 1mm also. In portal dosimetry the wider the field size the the higher the pixel value and as the lead thickness increase, the pixel value was exponentially decreased. Conclusions : The EPID was very suitable for QA tools and it can be used to measure exit dose during patients treatment with reasonable accuracy. But when indicate the EPID to clincal study deep consideration required

• 대한디지털의료영상학회논문지
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• 제10권1호
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• pp.21-28
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• 2008

Diagnostic display monitor QA according to AAPM TG18 is usually performed by PACS administrator, product manager and reading doctor, and for acceptance testing and periodic quality control evaluation, a combination of visual and quantitative tests can be used, as outlined in sections 5 and 6 of 'assessment of display performance for medical imaging systems'. Although many display tests can be performed visually, a more objective and quantitative evaluation of display performance requires special test tools. The required instruments vary in their complexity and cost, depending on the context of the evaluation(research, acceptance testing, or quality control) and how thorough the evaluation needs to be. Objective and reliable assessment of many display characteristics can be performed with relatively inexpensive equipment, So, we made 'AAPM TG18 guiding instrument' to ues variable purpose of the evaluation of 'geometrical distortions(quantitative"', 'veiling glare(visual)' and 'sensor calibration'. The spatial measurements for the quantitative evaluation of geometric distortions, and the measurement of the veling-glare ring response function which provides information regarding the spatial extent of the luminance spread, can be performed using the TG18 guiding instrument can be used to sensor calibration to standardize the basic rate of 0% luminance when periodic calibration.

• 산업진흥연구
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• 제3권1호
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• pp.43-48
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• 2018

본 연구는 기업 간 상생협력활동을 통한 동반성장이라는 목표 아래, 상생협력 분임조 혁신활동의 선도모델 개발 및 활성화를 위하여 다음과 같은 연구를 수행하였다. 첫째, 최근 3개년(2014년~2016년)동안 국가품질상의 범주 내에서 실시된 전국 품질분임조 경진대회 상생협력 부문에 참여한 총 18개 기업들의 주요 발표문집을 중심으로 사례분석을 실시하였으며 문제점 및 개선방안을 도출하였다. 둘째, 2017년 전국 품질분임조 경진대회 상생협력부문의 심사기준을 분석하고 각 활동단계별 우수사례를 선정하여 최적화된 상생협력 분임조 혁신활동의 활동요령 가이드를 제시하였다. 셋째, 상생협력 분임조 혁신활동의 활성화 및 참여유도 확산을 위한 성과공유의 시스템 강화방안을 제안하였다. 이러한 기업 간 상생협력의 시스템 강화방안을 통하여 상생협력이 새로운 기업문화로 정착할 수 있도록 노력하는 한편 상생협력 기업 간 생산성 및 품질향상 등 기업경쟁력 제고를 바탕으로 기업 간 동반성장의 목표를 달성하는데 기여할 것으로 기대한다.