• 제목/요약/키워드: quality control standard

검색결과 1,215건 처리시간 0.026초

Motor Control IP Design and Quality Evaluation from the Viewpoint of Reuse (ICCAS 2004)

  • Lee, Sang-Deok;Han, Sung-Ho;Kim, Min-Soo;Park, Young-Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.981-985
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    • 2004
  • In this paper we designed the motor control IP Core and evaluate its quality from the viewpoint of IP reuse. The most attractive merit of this methodology, so called IP-based hardware design, is hardware reuse. Although various vendors designed hardware with the same specification and got the same functional results, all that IPs is not the same quality in the reuse aspect. As tremendous calls for SoC have been increased, associated research about IP quality standard, VSIA(Virtual Socket Interface Alliance) and STARC(Semiconductor Technology Academic Research Center), has been doing best to make the IP quality evaluation system. And they made what conforms to objective IP design standard. We suggest the methodology to evaluate our own designed motor control IP quality with this standard. To attain our goal, we designed motor control IP that could control the motor velocity and position with feedback compensation algorithm. This controller has some IP blocks : digital filter, quadrature decoder, position counter, motion compensator, and PWM generator. Each block's functionality was verified by simulator ModelSim and then its quality was evaluated. To evaluate the core, We use Vnavigator for lint test and ModelSim for coverage check. During lint process, We adapted the OpenMORE's rule based on RMM (Reuse Methodology Manual) and it could tell us our IP's quality in a manner of the scored value form. If it is high, its quality is also high, and vice versa. During coverage check ModelSim-SE is used for verifying how our test circuits cover designs. This objective methods using well-defined commercial coverage metrics could perform a quantitative analysis of simulation completeness. In this manner, We evaluated the designed motor control IP's quality from the viewpoint of reuse. This methodology will save the time and cost in designing SoC that should integrate various IPs. In addition to this, It can be the guide for comparing the equally specified IP's quality. After all, we are continuously looking forward to enhancing our motor control IP in the aspect of not only functional perfection but also IP reuse to prepare for the SoC-Compliant motor control IP design.

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분계점 붓스트랩 방법을 이용한 자기상관을 갖는 공정의 $\bar{X}$ 관리도 ($\bar{X}$ control charts of automcorrelated process using threshold bootstrap method)

  • 김윤배;박대수
    • 품질경영학회지
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    • 제28권2호
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    • pp.39-56
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    • 2000
  • ${\overline{X}}$ control chart has proven to be an effective tool to improve the product quality. Shewhart charts assume that the observations are independent and normally distributed. Under the presence of positive autocorrelation and severe skewness, the control limits are not accurate because assumptions are violated- Autocorrelation in process measurements results in frequent false alarms when standard control chats are applied in process monitoring. In this paper, Threshold Bootstrap and Moving Block Bootstrap are used for constructing a confidence interval of correlated observations. Monte Carlo simulation studies are conducted to compare the performance of the bootstrap methods and that of standard method for constructing control charts under several conditions.

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하수처리 활성오니공정의 에너지 절감을 위한 퍼지 제어 방법에 관한 연구 (A Study on Fuzzy Control Method of Energy Saving for Activated Sludge Process in Sewage Treatment Plant)

  • 남의석
    • 전기학회논문지
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    • 제67권11호
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    • pp.1477-1485
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    • 2018
  • There are two major issues for activated sludge process in sewage treatment plant. One is how to make sewage be more clean and the other is the energy saving in sewage treatment process. The major monitoring sewage qualities are chemical oxygen demand, phosphorus, nitrogen, suspended solid in effluent. These are transmitted to the national TMS(Telemetry Monitoring System) at every hour. If these exceed the environmental standard, the environmental charges imposed. So, these water qualities are to be controlled below the environmental standard in operation of sewage treatment plant. And recently, the energy saving is also important in process operation. Over 50% energy is consumed in blowers and motors for injection oxygen into aeration tank. So, with the water qualities to be controlled below the environmental standard, the energy saving also is to be accomplished for efficient plant management. Almost researches are aimed to control water quality without considering energy saving. AI techniques have been used for control water quality. AI modeling simulator provided the optimal control inputs(blower speed, waste sludge, return sludge) for control water quality. Blower speed is the main control input for activated sludge process. To make sewage be more clean, the excessive blower speed is supplied, but water quality is not better than the previous. In results, non necessary energy is consumed. In this paper we propose a new method that the energy saving also is to be accomplished with the water qualities to be controlled below the environmental standard for efficient plant management. Water qualities in only aeration tank are used the inputs of fuzzy models. Outputs of these models are chemical oxygen demand, phosphorus, nitrogen, suspended solid in effluent and have the environmental standards. In test, we found this method could save 10% energy than the previous methods.

감자 품질평가 현황과 전망 (Prospects and Status on Quality of Potato)

  • 김숭열
    • 한국작물학회지
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    • 제47권
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    • pp.135-139
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    • 2002
  • The standard of quality was required to promote the consumption of potato and produce the high quality processing products. It will contribute the stability for processing products and the marketability of potato. The quality was determined based on size of tuber and content of dry matter. Even though the criteria of potato quality was involved many characters of tubers, the most important things were grading and packing of potato to create the consumption. For processing of raw materials, the standard of tubers had create between producer and processor according to size of tuber and content of dry matter. The evaluation of quality was performed over the standard to enhance the control of quality. In addition, the seed potato should be taken the evaluation to disease in the field during the period of cultivation and managed under the strict regulation in storage before release to farmer. Then, the producer of seed potato will make a good relationship to farmer with high quality tubers.

로버스트 추정에 근거한 수정된 다변량 $T^2$- 관리도 (Modified Multivariate $T^2$-Chart based on Robust Estimation)

  • 성웅현;박동련
    • 품질경영학회지
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    • 제29권1호
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    • pp.1-10
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    • 2001
  • We consider the problem of detecting special variations in multivariate $T^2$-control chart when two or more multivariate outliers are present. Since a multivariate outlier may reflect slippage in mean, variance, or correlation, it can distort the sample mean vector and sample covariance matrix. Damaged sample mean vector and sample covariance matrix have difficulty in examining special variations clearly, An alternative to detection outliers or special variations is to use robust estimators of mean vector and covariance matrix that are less sensitive to extreme observations than are the standard estimators $\bar{x}$ and $\textbf{S}$. We applied popular minimum volume ellipsoid(MVE) and minimum covariance determinant(MCD) method to estimate mean vector and covariance matrix and compared its results with standard $T^2$-control chart using simulated multivariate data with outliers. We found that the modified $T^2$-control chart based on the above robust methods were more effective in detecting special variations clearly than the standard $T^2$-control chart.

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건설공사 품질.안전.환경 통합관리를 고려한 해외 사례 고찰 (An advanced nation's case study considering integrated control for construction work quality.safety.environment)

  • 김동희;김운수;정한교;노정원
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2008년도 정기학술발표대회 논문집
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    • pp.819-823
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    • 2008
  • 현재 국내의 건설공사 품질관리, 안전관리, 환경관리는 각각의 법령을 기반으로 고유특성에 맞게 발전되어와 통합을 위한 기반이 형성되어 있지 못하다. 즉, 인력에서는 품질관리자와 안전관리자를 법적 배치인력으로 정하고 있으나, 환경관리자는 법적 배치인력이 아니다. 또한 품질관리계획은 KS A ISO 9001 규격의 모든 요구사항이 반영되어 PDCA(계획-실행-체크-조치) 시스템으로 업무를 수행하도록 되어 있으나, 안전관리계획 및 유해 위험방지계획은 KOSHA 18001 규격 요구사항 중 4항 실행(D) 및 운영에만 치중되어 P(계획), C(체크) 및 A(조치) 시스템이 제대로 반영되어 있지 못하다. 더욱이 환경관리계획은 수립기준조차 마련되어 있지 못한 실정이다. 이에 건설공사 품질 안전 환경 통합관리 기준을 마련함에 앞서 해외의 건설공사 운영사례를 조사하여 국내 적용가능성을 검토하고자 하며 본고에서는 싱가폴의 건설공사 운영사례를 살펴보기로 한다.

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대학생 대상 급식시설의 김밥 생산과정에 따른 계절별 미생물적 품질평가 (The Seasonal Microbiological Quality Assessment of Kimbap(seaweed roll) Production flow in Foodservice facilities for Univ. students - HACCP model -)

  • 이혜상;류승연
    • 한국식품조리과학회지
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    • 제14권4호
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    • pp.367-374
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    • 1998
  • The purpose of this study was to evaluate the microbiological quality of, and to assure the hygienic safety of, the kimbap production in the university foodservice facilities in accordance with the HACCP (Hazard Analysis Critical Control Point) Program. The time-temperature relationship and the microbiological quality (specifically, total plate count and coliform bacteria count) were assessed to find the critical control point (CCP) during each of the production phases. The average of the daily longest duration time of the kimbap at the facilities was 23.4 hours in summer, while 29.6 hours in winter. In the purchasing phase of the raw materials, the microbiological quality of laver, fish paste, carrot and cucumber in summer was not at an acceptable level according to the standard set by the Natick research center, especially the number of TPC and the coliform level of laver was higher than the threshold level. In the refrigerator storage phase, the temperature of the carrot was 7.4$^{\circ}C$. This temperature is far exceeding the standard so that the microbiological counts was increased by the 2 log cycle during the average storage time of 17 hours or more. In the preparation phase, the temperature of the blanching is too low compared to the standard. In the holding phase before serving, its time-temperature relationship was out of the FDA food code standard both in winter and summer. In the sewing phase, the number of microbiological count was higher than the threshold level in summer while that in winter was up to standard. According to the Harrigan and McCance standard, the number of microbiological count of the utensils was higher than the threshold level in summer while that in winter was up to standard.

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삼차원 프린팅 기술을 이용한 전산화단층영상 품질 측정용 팬텀 제작 및 비교 연구 (A Study on the Fabrication and Comparison of the Phantom for Computed Tomography Image Quality Measurements Using Three-Dimensions Printing Technology)

  • 윤명성;홍순민;허영철;한동균
    • 대한방사선기술학회지:방사선기술과학
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    • 제41권6호
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    • pp.595-602
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    • 2018
  • Quality control (QC) of Computed Tomography (CT) devices is based on image quality measurement on AAPM CT phantom which is a standard phantom. Although it is possible to control the accuracy of the CT apparatus, it is expensive and has a disadvantage of low penetration rate. Therefore, in this study, we make image quality measurement phantom at low cost using FFF (Fused Filament Fabrication) type three-dimensional printer and try to analyze the usefulness, compare it with existing standard phantom. To print a phantom, We used three-dimensional printer of the FFF system and PLA (Poly Lactic Acid, density: $1.24g/cm^3$) filament, and the CT device of 64 MDCT (Aquilion CX, Toshiba, Japan). In addition, we printed a phantom using three-dimensional printer after design using various tool based on existing standard phantom. For image quality evaluation, AAPM CT phantom and self-generated phantom were measured 10 times for each block. The measured data were analyzed for significance using the Mannwhiteney U-test of SPSS (Version 22.0, SPSS, Chicago, IL, USA). As a result of the analysis, phantom fabricated with three-dimensional printer and standard phantom showed no significant difference (p>0.05). Furthermore, we confirmed that image quality measurement performance of a phantom using three-dimensional printer is similar to the existing standard phantom. In conclusion, we confirmed the possibility of low cost phantom fabrication using three dimensional printer.

기술사마당 - 국격과 정책품질관리(國格과 政策品質管理) (A State Standard and Policy Quality Control)

  • 정병현
    • 기술사
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    • 제46권1호
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    • pp.58-63
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    • 2013
  • 2010년 이래 '국격'이라는 말이 정치지도자들이나 네티즌들 사이에 많이 회자되고 있다. 규격/표준은 '사실상의 표준[de facto standard]'과 '공적표준[de jure standard]'이 있다. 국가품질수준을 말하는 국격은 그 국가의 헌법에 규정되고 있는 내용이다. 국가의 공적인 표준인 헌법이 아무리 수준 높게 잘 제정되고 있어도 잘 준수되지 않으면 사실상의 국격은 낮게 인식된다. 한 두 프로젝트의 성공이나 어떤 정책의 성공이 당장 국격을 향상시킬 수 있는 것은 아니다 국격을 생각하는 사람은 과학과 기술을 생각해야 하는 시대이다.

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Investigation of Standard Evaluation for the Quality Control of General X-ray Systems

  • Kang, Byung-Sam;Son, Jin-Hyun;Kim, Byoung-Jun;Park, Deok-Woo;Jung, Byoung-Hoon;Lee, Hyo-Jin;Hong, Ji-Young;Kim, Seung-Chul
    • 대한디지털의료영상학회논문지
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    • 제12권2호
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    • pp.71-79
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    • 2010
  • Thanks to the great development of technology in radiation, we are now able to reduce radiation exposure to the patients, and the radiographer and expenses in medical sector. We are also trying to produce ideal images which maintain useful information. These kinds of effort are increasing over the world. For that reason, we should get images which include necessary data of patients. Then it also can help to reduce radiation exposure to the patients. Therefore, we need to know the problems that cause a falling off in image's quality and check on generator in case of their electronic and mechanical errors. And moreover, we should anticipate the possibility of devices errors and prevent them with regular quality control. This investigation was conducted in medical institutions, institute of educations and hospitals. They are all in Seongnam-City. We used PMX-III, kVp meter to implement kVp test, mR / mAs output test, light fiel / beam alignment test, Reproducibility of exposure dose, half value layer test, reproducibility of exposure time test. in the case of hospitals, they perceive the importance of regular quality control and organize the regular quality control team so they can be satisfied with the error standard in most experiments. On the other hand, when it comes to medical institutions and institute of educations, they perceive the importance of regular quality control less than hospitals do. Radiographer need to understand the importance of regular quality control and practice it so they can get the fine ideal image with the lower dose to the patient.

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