• 제목/요약/키워드: Quality control materials

검색결과 1,115건 처리시간 0.031초

설계된 구조물을 사용한 건설의 필요성 (Necessity of Construction Using Designed Structure)

  • 김덕현;한봉구
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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    • pp.428-434
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    • 2002
  • Almost all buildings/infrastructures made of composite materials are fabricated without proper design. Unlike airplane or automobile parts, prototype test is impossible. One cannot destroy 10 story buildings or 100 meter-long bridges. In order to realize “composites in construction”, the following subjects must be studied in detail, for his design: Concept optimization, Simple method of analysis, Folded plate theory, Size effects in failure, and Critical frequency Unlike the design procedures with conventional materials, his design should include material design, selection of manufacturing method, and quality control methods, in addition to the fabrication method.

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공업용 냉각수의 문제점과 처리법 (Problems and Control Measures of Industrial Cooling Water)

  • 배종수;이규화
    • 한국기계연구소 소보
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    • 통권16호
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    • pp.117-126
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    • 1986
  • Trouble-free operation of cooling water systems is essential for efficient pro¬duction in most industrial facilities. Improper water treatments frequently cause such problems as corrosion, scaling, fouling and slime formation. Water quality, methods of cooling and materials of construction in the cooling circuit should be carefully studied before making selection of the water treatment programs. This paper reviewed cooling water problems encountered frequently in the open recirculating cooling systems and discussed the counter measures how to cope with them.

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The Design Method and Error Analysis of Machine Electronic Weighing Burden System controlled by a Computer Automatically

  • Zhang, Zhengou;Lin, Shanling
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.768-778
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    • 1993
  • The system is designed for the production and processing of feed, fertilizer, sugar , and grain. It can be used to weigh and transport automatically their pellet, power or nonstickness materials. In this system, we use discontinuous totalising automatic weighing instruments to weigh materials. It is a closed-cycle control system controlled by industrial controlling computer STD bus. The system used for processing grain and feed can improve the quality of products , carry out scientific management, increase productivity and decrease the intensity of labour

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친환경 황토 가공 신소재가 장어의 품질 특성에 미치는 영향 (Effect of Environmetally-friendly Red Clay-Processed Materials on Quality Characteristics of Eel)

  • 서유진;길범주;경진석;유병승;장윤혁;유성률;이영승
    • 한국식품영양과학회지
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    • 제43권2호
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    • pp.287-292
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    • 2014
  • 본 연구는 가공황토 처리여부에 따른 장어시료의 품질 특성을 비교하고자 장어를 양식장에서 동일한 조건으로 사육하여 일반성분, 물성, 영양소, 기능적 특성 및 관능적 특성을 분석하였다. 그 결과 일반성분 분석에 대해서는 두 군 간의 차이가 없었으며 niacin은 실험구가 무처리 대비 더 높은 함량을 나타냈다. Tocopherol은 가공황토소재로 양식한 시료에서 무처리구 대비 약 3배 이상의 tocopherol 함량이 측정되었다(P<0.05). 냉 해동 저장기간 동안 실험구가 무처리구 대비보다 안정된 조직감을 나타냈다. DPPH 라디칼 소거능과 FRAP value 분석 결과, 실험구의 항산화 활성이 유의적으로 높은 것을 확인할 수 있었다. 묘사분석 결과 '기름진 정도'가 무처리구에 비하여 실험구에서 낮게 평가되었으며, 이는 보다 담백하면서 기능성이 강화된 장어의 생산이 가능함을 나타낸다고 할 수 있다. 따라서 친환경 가공황토소재로 양식한 장어의 경우 기능성이 강화되고 맛이 향상된 고부가가치 제품으로 생산이 가능하여 국내 장어 시장을 한 단계 업그레이드할 수 있을 것으로 사료된다.

화학 분석 결과의 QA/QC를 위한 측정 불확도 (Measurement uncertainty for QC/QA applied to the chemical analysis)

  • 우진춘;오상협;김병문;배현길;김광섭;김용두
    • 분석과학
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    • 제18권6호
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    • pp.475-482
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    • 2005
  • 화학분석 분야에는 ISO 17025에 따른 체계적 품질 관리/보증의 요구가 커지면서, 측정 불확도의 표기가 크게 요구되고 있다. 측정품질의 정량화를 위하여, 화학분석의 QA/QC 문헌들로부터 화학분석 품질에 영향을 미치는 중요한 불확도 요소를 선정하였고, 이것을 측정결과 평가 요소의 기본인 7개의 품질요소로서 반복성, 직선성, 소급성, 변동성, 매질효과, 균질성, 안정성으로 구분하였다. 화학분석의 QA/QC를 위한 이 7대 품질 요소의 측정 모델화, 표준불확도의 계산 및 합성방법을 각각 예로서 제시하였다.

A Reform Program for Reliability Insurance Rate-Making System

  • Hong, Yeon-Woong
    • Journal of the Korean Data and Information Science Society
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    • 제16권2호
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    • pp.263-270
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    • 2005
  • The reliability guarantee insurance policy for parts and materials was introduced to the market in 2003. This policy indemnifies manufactures for the repair/failure costs, recall expenses. In this paper, owing to the nature of the policy, we propose a new rate-making system considering the type of product and industry, quality control circumstances, record of guarantee performance, and exposures.

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변속제어 알고리즘을 적용한 휠로더 자동변속기 특성 해석 (Characteristics Analysis of Automatic Transmission for the Wheel-Loader with Shift Control Algorithm)

  • 오주영;윤웅권;박영준;이근호;송창섭
    • 한국생산제조학회지
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    • 제20권5호
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    • pp.639-645
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    • 2011
  • Wheel-loader is a construction vehicle for uploading soil or sand into truck and transportation of materials, which requires large driving power and high rotational speed. To improve the working efficiency, the operator has to shift gears and control levers for bucket & boom simultaneously. Therefore, the automatic transmission has been introduced to enhance operator's convenience and enable effective operation. To develop the automatic transmission for the wheel-loader, technologies such as gears and a clutch-pack design and shift algorithm are required for improvement of shift quality. In this paper, the shift algorithm for the wheel-loader was developed and its shift pattern was analyzed. As the shift control is affected by the pressure profile for the clutch control, the shift quality depending on the pressure profile has been evaluated using experiment and simulation model analysis.

소형 FWD와 반복평판재하시험에서의 변형계수(Ev2)와의 상관관계 평가 (Evaluation of correlation between Strain mudulus (Ev2) and Deformation modulus (ELFWD) Using Cyclic Plate loading Test and LFWD)

  • 최찬용;이성혁;배재훈;박두희
    • 한국지반신소재학회논문집
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    • 제10권3호
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    • pp.33-41
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    • 2011
  • 본 논문에서는 국내 건설현장 29개 지점에서 국내 철도노반 다짐품질관리 방법인 반복평판재하시험과 LFWD(Light Falling Weight Deflection)에서 구한 변형률계수(Ev2)와 변형계수($E_{LFWD}$)에 대하여 응력보정을 통해 자갈재료와 사질토에 대하여 상관성을 비교하였다. 실험결과 대부분 다짐품질관리 기준을 만족하고 있으며, 입상재료의 경우 관리기준치에 약 3배이상 값을 나타내었다. 두 시험방법에 따른 상관성은 토사의 경우에는 서로 상관성이 높은 것으로 나타났지만, 강성이 상대적으로 큰 입상재료의 경우 두 시험간의 상관성이 적은 것으로 나타났다. 또한, 시험방법 별로 탄성계수를 구하여 응력상태를 보정한 후 회귀 분석한 결과 응력 보정하지 않는 조건보다 상관성이 더 높게 나타났다.

A new validated analytical method for the quality control of red ginseng products

  • Kim, Il-Woung;Cha, Kyu-Min;Wee, Jae Joon;Ye, Michael B.;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • 제37권4호
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    • pp.475-482
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    • 2013
  • The main active components of Panax ginseng are ginsenosides. Ginsenoside Rb1 and Rg1 are accepted as marker substances for quality control worldwide. The analytical methods currently used to detect these two compounds unfairly penalize steamed and dried (red) P. ginseng preparations, because it has a lower content of those ginsenosides than white ginseng. To manufacture red ginseng products from fresh ginseng, the ginseng roots are exposed to high temperatures for many hours. This heating process converts the naturally occurring ginsenoside Rb1 and Rg1 into artifact ginsenosides such as ginsenoside Rg3, Rg5, Rh1, and Rh2, among others. This study highlights the absurdity of the current analytical practice by investigating the time-dependent changes in the crude saponin and the major natural and artifact ginsenosides contents during simmering. The results lead us to recommend (20S)- and (20R)-ginsenoside Rg3 as new reference materials to complement the current P. ginseng preparation reference materials ginsenoside Rb1 and Rg1. An attempt has also been made to establish validated qualitative and quantitative analytical procedures for these four compounds that meet International Conference of Harmonization (ICH) guidelines for specificity, linearity, range, accuracy, precision, detection limit, quantitation limit, robustness and system suitability. Based on these results, we suggest a validated analytical procedure which conforms to ICH guidelines and equally values the contents of ginsenosides in white and red ginseng preparations.

의약품의 적정 사용을 위한 전략 (Strategies to Improve Use of Medicines)

  • 박실비아
    • 한국의료질향상학회지
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    • 제12권2호
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    • pp.93-112
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    • 2006
  • This study reviewed published studies on interventions used by hospitals, health insurance programs, or governments to improve use of medicines in foreign countries. Interventions to improve use of medicines are classified into two categories: 1) information strategies-dissemination of educational materials, group education, one-to-one educational outreach, drug utilization review, and feedback; 2) managerial strategies- formularies, prior authorization, and financial incentives. Dissemination of educational materials, which is a common intervention, was unsuccessful in changing physicians' prescribing behaviors. Problem-based small group education was more likely to change behaviors than didactic large group education. One-to-one educational outreach(academic detailing) was among the most effective strategies used to change prescribing behaviors. Prospective drug utilization review (DUR) program was more successful in improving use of medicines than retrospective DUR program. Feedback intervention has been reported to be ineffective to change behaviors. Formularies are frequently used to control medication use by most health insurance programs. Financial incentives provide physicians economic incentives according to appropriateness of prescribing. However, few published studies have assessed the efficacy of formularies or financial incentives. Prior authorization requires physicians to get authorization from health insurers before prescribing a certain group of drugs which is usually of high costs or risk. There is no magic bullet for quality use of medicines. Multifaceted interventions that help to predispose, enable, and reinforce desired behaviors are more likely to be successful.

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