• Title/Summary/Keyword: Quality control materials

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

  • 김덕현;한봉구
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.10a
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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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Problems and Control Measures of Industrial Cooling Water (공업용 냉각수의 문제점과 처리법)

  • Bae, Jong-Su;Lee, Gyu-Hwa
    • 한국기계연구소 소보
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    • s.16
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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
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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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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Effect of Environmetally-friendly Red Clay-Processed Materials on Quality Characteristics of Eel (친환경 황토 가공 신소재가 장어의 품질 특성에 미치는 영향)

  • Seo, Yoojin;Gil, Beomju;Kyoung, Jinsuk;Yoo, Byoungseung;Chang, Yoonhyuk;Yu, Sungyul;Lee, Youngseung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.2
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    • pp.287-292
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    • 2014
  • The objectives of this study were to examine the effects of red clay-processed nano-materials (RCPM) on the quality characteristics of eel (Anguilla japonica). Both eels treated with RCPM and control were farm-raised under identical environments and were commercially processed. General components, texture, nutrients, antioxidant activities, and sensory analysis were performed. RCPM-treated eels showed significantly higher DPPH radical scavenging activities and FRAP values than the of control, indicating higher antioxidant activities of eels raised by RCPM. The amounts of niacin and tocopherol in RCPM-treated eels were higher than those of the control. For analysis of freeze-thaw stability, RCPM-treated eels showed more stable texture over freeze-thaw three treatment cycles. Descriptive panelists perceived eels raised by RCPM to be less oily than the control. Overall, RCPM exhibited positive effects on the quality of farm-raised eels. Therefore, RCPM would be of benefit to produce high value-added eels of premium quality.

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

  • Woo, Jin-Chun;Oh, Sang-Hyub;Kim, Byoung-Moon;Bae, Hyun-Kil;Kim, Kwang-Sub;Kim, Young-Doo
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.475-482
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    • 2005
  • The expression of uncertainty applied to the chemical analysis is highly recommended with increasing demands upon the systematic quality assurance and control(QA/QC) with ISO 17025. For the quantification of quality source, 7 major common sources of uncertainty, normally contributing to the quality of the chemical analysis, were selected from QA/QC literatures of chemical analysis. They were classified into repeatability, drift, uncertainty in standards, linearity of calibration, homogeneity, stability of sample, and matrix effect. And, the quantification of the sources by means of measurement uncertainty was proposed as a prerequisite steps for QA/QC. Examples applied to the quantification procedures of modelling, combination and expression of standard uncertainty for the 7 major common sources were presented as a reference guide for QA/QC in chemical analysis.

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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    • v.16 no.2
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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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Characteristics Analysis of Automatic Transmission for the Wheel-Loader with Shift Control Algorithm (변속제어 알고리즘을 적용한 휠로더 자동변속기 특성 해석)

  • Oh, Joo-Young;Yun, Ung-Kwon;Park, Young-Jun;Lee, Geun-Ho;Song, Chang-Seop
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.5
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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.

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

  • Choi, Chan-Yong;Lee, Sung Hyok;Bae, Jae Hun;Park, Doo Hee
    • Journal of the Korean Geosynthetics Society
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    • v.10 no.3
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    • pp.33-41
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    • 2011
  • In this study, it conducted a compaction quality control test in 29 domestic construction sites and investigated the relationship between classical method (Cyclic Plate bearing test) and LFWD test with subgrade materials which consist in sandy soil and gravelly soil. According to the test results, the most of soil types were mostly satisfied with specification criterion and gravelly soils were easily satisfied with values over 3 times greater than specification criterion. In term of the correlation relation of soil modulus with the two compaction quality control test methods, it is shown that the sandy soil types were a good correlation, while gravelly soil types with a high stiffness materials were indicated less correlation. After the compensation for stress condition, a linear regression for elastic modulus were higher correlation.

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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    • v.37 no.4
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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.

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

  • Park, Sylvia
    • Quality Improvement in Health Care
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    • v.12 no.2
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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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