• 제목/요약/키워드: Rework

검색결과 137건 처리시간 0.026초

Process Reliability Improvement and Setup Cost Reduction in Imperfect Production System

  • Lee, Chang-Hwan
    • 한국경영과학회지
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    • 제22권4호
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    • pp.93-113
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    • 1997
  • In studying an EOQ-like inventory model for a manufacturing process, a number of findings were made. The system can "go out of control" resulting in a relatively minor problem state or "break-down". When the production system is in the minor problem statei produces a number of defective items. It is assumed that each defective piece requires rework cost and related operations. Once the machine breakdown takes place, the production system produces severely defective items that are completely unusable. Each completely unusuable item is immediately discarded and incurs handling cost, scrapped raw material cost and related operations. Two investment options in improving the production process are introduced : (1) reducing the probability of machine breakdown, breakdowns, and (2) simultaneously reducing the probability of machine breakdowns and setup costs. By assuming specific forms of investment cost function, the optimal investment policies are obtained explicitly. Finally, to better understand the model in this paper, the sensitivity of these solutions to changes in parameter values and numerical examples are provided.amples are provided.

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자동차 외형설계곡면의 검사를 위한 효율적인 반사선의 생성 (Efficient generation of reflection lines to evaluate car body surfaces)

  • 최인진;이건우
    • 한국CDE학회논문집
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    • 제2권3호
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    • pp.133-141
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    • 1997
  • In the process of car body design, various surfaces are generated from the given boundary curves. Depending upon the method of the surface generation and the quality of the boundary curves provided, the resulting surfaces may have global or local irregularities in many cases. Thus it would be necessary for the designer to evaluate the surface quality and to modify the surface or to use the different generation method based on the evaluation results. This capability is very important because the defect of the surface quality detected in the production stage will require the rework of the dies and will cause a big loss in cost and time. A method of surface interrogation using reflection line is introduced. In this paper, We applied reflection mapping to generate reflection lines on the trimmed NURBS surface. Since reflection lines are obtained from reflection mapping that uses simple and physically acceptable mapping algorithm, they can be efficiently used to simulate the reflection test on the real part in the production line.

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전자식 모터제어 시스템 개발 (A Development of Electronic Motor Control Systems)

  • 이성환;이석주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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    • pp.76-78
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    • 2000
  • The previous MCC's have the demerits of high cost and much manhour for rework because they are impossible for the standardization of products and have many manual connections. The customers require the products which can operate in connection with SCADA system by digitalizing the functions of the current MCC's and are systematized with capability of remote control. To solve these disadvantages and requirements, we developed the Electronic Motor Control System according to starting type for applying to fields based on this. This system has the various functions such as protection, measurement, and communication. Using these functions, it can monitor motor status through communication with the upper system and define the circuit for lower connection cost according to starting type and shorter manufacture period by program. The development of this product results in establishment of competitive structure with domestic competition and perfect automatic monitoring through linkage with SCADA system. In addition, it provides the comparable dominancy of receiving on orders in switch gear and adaptability to change of MCC market in Japan and Europe.

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진동가속도센서를 이용한 Reduction Gear Box Noise 검출시스템 개발 (A Development of Noise Detection System Utilizing the Vibrating Accelerative Sensor for the Reduction Gear Box)

  • 천종필;편영식
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.274-279
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    • 2009
  • Reduction Gear Box where from productive site uses the gear with power delivery with high mechanical efficiency of power a deceleration and as the mechanical element union product which has the velocity ratio which is various together is produced with the power occurrence motor and leads gets a high driving force is plentifully used. The above occurs from gear drive issue sound Whine, Noise and Vibration as occurring from the rim process which the gear will bite mainly is delivered with the case etc. gear drive whole which leads the axis and the bearing. The productivity falls with the going straight rate decrease which with like this problem point is caused by with rework the problem point where the cost of production rises under improving boil many kinds analyzed the plan and investigates the resultant acceleration sensor which and a frequency analysis system and was made to apply.

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시각감시장치를 이용한 분말야금 공정의 검사자동화 기술개발에 관한 연구 (A study on automatic testing of powder metallurgy process using the visual inspection system)

  • 권기룡;최재완;최성락
    • 제어로봇시스템학회논문지
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    • 제3권1호
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    • pp.89-93
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    • 1997
  • This paper describes the automatic testing system developed for powder metallurgy process using the visual inspection, and its some internal algorithms. The system consists of one unit from each of the five types of units; feeding, slot, vision inspection, volumn counter, and inferior good extractor units. Some applications of the system to powder metallurgy process has shown the possibility of reducing the rework and increasing the efficiency of operation.

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6시그마 방법론을 이용한 웹 사이트 디자인 (Web Site Design Using 6 Sigma Methodology)

  • 성기욱;김봉선
    • 대한안전경영과학회지
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    • 제11권2호
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    • pp.205-214
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    • 2009
  • Today, many of communication methods based on print media traditionally has moved to the internet. As increase of interest in internet business, effective web site design is needed. While the researches for the evaluation of completed web site are increased, that of web site design procedures are rare. In the design process occur various problems : rework, delay, etc.. In this paper are presented the improved procedures of web site design using 6 sigma methodology. The main object of this study is to introduce an empirical study on DIDOV.

비용 흐름의 차이를 고려한 교체 설비 대안에 대한 타당성 평가 (The Evaluation of the Validity of Equipment-replacing Alternatives in Consideration of the Differences of Cost Flow)

  • 김성집;박흥석
    • 산업경영시스템학회지
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    • 제17권31호
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    • pp.99-114
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    • 1994
  • The introduction of new equipments to strengthen the competitiveness of enterprises is one of pretty important factors. Enterprises introducing new equipments strengthen competitiveness through productivity increasing, high quality maintenance, inventory reduction, improved design and production interface, simple scheduling process, low scrap rate, rework reduction, etc. Managers will work out the best equipment-replacing strategy through the appropriate combination of potential cost attributes and qualitative attributes difficult to quantify in accordance with the business purpose. This study is to present a method to select an equipment-replacing alternative through the decision-making model of Analytic Hierarchy Process in consideration of the differences of cost flow of the alternatives, taking into consideration tangible attributes and strategic intangible attributes.

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Economic Decision of Specification Limits for a Ham Production Process - An Industrial Case Study -

  • Cha, Young-Joon;Hong, Yeon-Woong;Lee, Jae-Man
    • Journal of the Korean Data and Information Science Society
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    • 제16권4호
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    • pp.943-949
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    • 2005
  • An economic design of specification limits for production process of ham is considered for a given process mean in a complete inspection plan. Each ham is inspected, and if it meets the specification, it is accepted. The ham less than the lower specification limit are changed another products or at a discounted price, and those greater than the upper specification limit are reworked. A profit model is developed which involves selling price, production cost, rework cost and the cost which is incurred by imperfect quality. Methods for finding the optimal specification limits are derived for the case of piecewise linear loss function with an industrial case study.

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디지털 보호 계전기를 이용한 모터 보호 및 제어 (Motor Protection and Control with Digital Protective Relays)

  • 이성환;안인석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.178-178
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    • 2000
  • In this paper, intelligent methods using digital protection relay in power management and control system is developed in order to protect power systems by means of timely fault detection during operation and control at starting for induction motor which have various load environments and capacities in power systems. The digital protective relay was designed with DSP CPU(TMS320C31) to Protect and measure more quickly and precisely. The test result on the basis of KEMCl120 and IEC60255, show that the operation time error of the digital motor protection relay is improved within $\pm$5%. Also, we can control motors at starting according to starting types with simple method as programmable sequence editor. So we can improve the demerits of high cost and much manhour for rework.

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연속생산공정에서 공정목표값과 검사규격한계의 경제적인 결정에 관한 연구 (A Study on Economic Selection of the Process Target and the Screening Specification Limits in a Continuous Production Process)

  • 백종석;윤덕균
    • 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.

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