• Title/Summary/Keyword: Quality control materials

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A Study of Developing Guides for the Construction Site Quality Control of Porous Concrete (투수콘크리트 현장품질관리 지침서 개발에 관한 연구)

  • Ko, Eun-Jung;Goh, Eun-Joo;Seok, Ho-Joong;Lee, Seung-Hyeok
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.3
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    • pp.65-71
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    • 2009
  • General criteria for the quality of porous concrete have not been established yet in Korea. And yet, pavement and construction have been performed. In this paper, guidelines on the construction site quality control of porous concrete were developed in order to establish criteria for resolving the issues and problems of porous concrete, to establish methods for improving poor performance, and to manage porous concrete more systematically. In addition, a guide for the construction site quality control of porous concrete, which was appropriate for reality, was developed by researching several quality control guides and maintenance at construction sites. The guide consists of a total of nine chapters such as Application Range, Overview, the Structure of Porous Concrete, the Design of Package Thickness, Package Materials for Porous Concrete, Construction Methods, Quality Assurance and Inspections, Construction Site Quality Control, and Maintenance. It describes quality control guidelines in all steps such as methods for transporting porous concrete from the factory to the construction site, cautions for construction work at construction sites, maintenance, and management. The Guide for the Construction Site Quality Control of Porous Concrete is expected to ensure the quality of porous concrete, to reduce national costs for quality assurance, and to help ensure the health and safety of Korean people.

Effect of specific gravity and annual ring width on the acoustical properties of European lumber used in violin making (유럽산 바이올린 용재의 비중과 년륜폭이 소재의 음향적 성질에 미치는 영향)

  • 정우양;홍병화
    • Journal of the Korea Furniture Society
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    • v.10 no.1
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    • pp.57-63
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    • 1999
  • This study was carried out to analyze the relationship between basic physical properties and acoustical characteristics of imported violin wood and to offer the information on raw material procurement and incoming-material quality control to domestic violin makers which have purchased most raw materials from European exporting countries at high expense. Equilibrium moisture content of European spruce with lower specific gravity after the prolonged storage was rather higher than that of European maple with higher specific gravity. The specific gravity of spruce increased with decreasing annual ring width, however, that of narrower annual ring. Increasement in specific gravity enhanced the dynamic Young's modulus of both wood species, but influenced the vibration energy loss by internal friction differently between two species. For dynamic MOE, qurater-sawn spruce was higher than the flat-sawn, but maple showed the reverse directional characteristics. Consequently, it would be well for violin makers to establish the standard for materials and quality control system to assure the quality of their violin products.

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Effect of Natural Materials on Growth and Quality of Chinese Cabbage (天然物質 處理가 배추의 生長과 品質에 미치는 영향)

  • Kim, Kyung-Je;Lee, Byung-Moo
    • Korean Journal of Organic Agriculture
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    • v.10 no.4
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    • pp.37-45
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    • 2002
  • This study was conduction to investigate the effects of natural materials such as $GB_{10}$ chitofarm, chaff charcoal, and chaff charcoal sap, on quality and yield of chinese cabbage, Natural materials were treated on seeds soil, and leaves. The total plant weight, head weight, head length, head width, leaf length, leaf width, and sugar content of chinese cabbage in treatment with natural materials showed significant difference compared with control. The yield of chinese cabbage in $GB_{10}$ soil treatment and 1% $GB_{10}$ leaf treatment was increased 53% compared with control. The total nitrogen $P_2O_5$, $K_2O$, CaO, MgO, $Na_2O$, and Mn in total plant were analyzed. The chemical components were increased in total plant of chinese cabbage treated with natural materials compared with control natural materials increased the quality of chinese cabbage.

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Controlling of the heterogeniously growing GaN polycrystals using a quartz ring in the edge during the HVPE-GaN bulk growth

  • Park, Jae Hwa;Lee, Hee Ae;Park, Cheol Woo;Kang, Hyo Sang;Lee, Joo Hyung;In, Jun-Hyeong;Lee, Seong Kuk;Shim, Kwang Bo
    • Journal of Ceramic Processing Research
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    • v.19 no.5
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    • pp.439-443
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    • 2018
  • The outstanding characteristics of high quality GaN single crystal substrates make it possible to apply the manufacture of high brightness light emitting diodes and power devices. However, it is very difficult to obtain high quality GaN substrate because the process conditions are hard to control. In order to effectively control the formation of GaN polycrystals during the bulk GaN single crystal growth by the HVPE (hydride vapor phase epitaxy) method, a quartz ring was introduced in the edge of substrate. A variety of evaluating method such as high resolution X-ray diffraction, Raman spectroscopy and photoluminescence was used in order to measure the effectiveness of the quartz ring. A secondary ion mass spectroscopy was also used for evaluating the variations of impurity concentration in the resulting GaN single crystal. Through the detailed investigations, we could confirm that the introduction of a quartz ring during the GaN single crystal growth process using HVPE is a very effective strategy to obtain a high quality GaN single crystal.

Effect of Coarse Materials on Compaction of Soil (조립재가 흙의 다짐에 미치는 영향)

  • 윤충섭;김호일;김현태
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.33 no.4
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    • pp.84-95
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    • 1991
  • The compaction ratio of the field dry density to the maximum dry density is generally adopted as the index of quality control for embankment of earthfill structures such as Earth Dam, Sea Dike, River Bank and Road. In case of coarse materials are included in the earth material, the compaction ratio will be varied in wide range since the dry density is influenced by quantity of coarse material in the soil. The treatment for the coarse material should be controlled carefully in testing. In this study, the compaction characteristics of the soil contained the coarse materials were researched and calibration of the suitability of field quality control methods were carried out. 28 Samples were made of clay(CL) and sandy soil (SM) mixed with gravel whose content were 0, 4, 6, 8, 10, 12, 15, 20, 25, 30, 35, 40, 45, and 60% in Weight. The compaction characteristics depending on the coarse material content were analysed through 4 types of compaction tests which are A-1, B-i, C-i and D-1. The adjusting coefficients for density and moisture content namely a and ${\beta}$ respectively were proposed in order to consider the effects depending on content of the coarse materials. The test methods to control reasonably and promptly the quality of earthfill were proposed after analysing the ranges of possible errors on the relative compaction ratio between laboratory compaction methods and field density testing methods.

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Improvement of Watertightness Evaluation Method in Waterproof Membrane (복합계 멤브레인 방수층의 수밀성 시험 평가방법 개선방안 연구)

  • Kim, Meong-Ji;Seon, Yun-Suk;Kim, Soo-Yeon;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.50-51
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    • 2018
  • Although the introduction of new materials and new construction methods and overseas materials has become more active due to the diversification of the construction market, the quality standards of waterproofing methods in Korea are insufficient. In particular, the quality control standard is applied to the KS F 2622:08 (Membrane Waterproofing layer performance test method), which is the existing standard, to prepare standards for quality control of waterproof materials, which is increased in Korea.

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Quality Control of Pharmacopuncture: A Comparative Study of Good Manufacturing Practice and External Herbal Dispensary Standards

  • Han, Ji-Eun;Park, Minjung;An, Tteul-E-Bom;Park, Jong-Hyun;Oh, Danny;Kim, Kyeong Han;Sung, Soo-Hyun
    • Journal of Pharmacopuncture
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    • v.24 no.2
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    • pp.59-67
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    • 2021
  • Objectives: We aimed to compare the external herbal dispensary (EHD) evaluation criteria for pharmacopuncture and the Korea Good Manufacturing Practice (KGMP) sterile medicine standards to contribute to the establishment of quality control criteria for pharmacopuncture. Methods: We obtained the KGMP standards from the Ministry of Food and Drug Safety and the pharmacopuncture certification criteria from the Ministry of Health and Welfare of South Korea. The EHD evaluation items were classified into three categories: facilities, quality control, and validation. The evaluation items were compared with the KGMP sterile medicine criteria to determine their conformance with each other, followed by a discussion among the committee of six experts and their consensus to suggest the items to complement the EHD evaluation criteria. Results: Among the KGMP sterile medicine criteria, 44 were related to the management of the facilities, and 32 pharmacopuncture evaluation items corresponded to these KGMP items (66.7%). Fifty-eight KGMP criteria were related to quality management, and 42 pharmacopuncture evaluation items corresponded to these KGMP items (72.4%). Twentyfive KGMP sterile medicine criteria were related to validation, and 11 pharmacopuncture evaluation items corresponded to these KGMP items (44.0%). Sixteen items under the pharmacopuncture EHD criteria corresponded to the KGMP sterile medicine criteria based on the consent of the experts. Among these, 4 were related to facility management, 6 were related to quality control, and 6 were related to validation. Conclusion: For the safety and quality control of pharmacopuncture, there is a need to select the criteria for the mandatory items among the proposed pharmacopuncture-EHD criteria laws and systems to ensure that the pharmacopuncture materials are produced under the pharmacopuncture-EHD in compliance with the relevant requirements. More studies are needed to secure the safety level of pharmacopuncture materials corresponding to that of conventional medicine.

Efficient Application of Westgard Multi-Rules and Quality Control Implementation Improvement (Westgard Multi-Rules의 효율적 적용과 조치사항의 개선)

  • Jung, Heung Soo;Oh, Youn Jung;Bae, Jin Soo;Baek, Jin Young;Hwang, Bo ra;Shin, Yong Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.1
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    • pp.60-64
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    • 2017
  • Purpose Westgard multi-rules application based on test quality improvement and commercialized international standard has been widely used in quality control. However, it is difficult to applicate the Westgard multi-rules in nuclear medicine in vitro tests due to the larger sample sizes and the simultaneous measurement of quality control material and patient sample. This study investigated the usefulness of Westgard multi-rules application in nuclear medicine in vitro tests. Materials and Methods A total of 282 systematic error multi-rules (22s, 101s) recorded in the samsung medical center computer system from January 2013 to June 2016 along with 117 cases of corrective measure record was analyzed. The Quality control implementation is recorded in Hospital information system were divided into 4 high-level areas including quality control material error, experimental procedural error, Kit lot number management error, and others. To prevent quality control material error, the existing method that each staff used their own method was changed. The staff who in charge of managing the quality control material was designated and daily consumption amount of every test was strictly controlled by one person. To prevent other errors, every test step was standardized so that the entire test procedures are identically implemented. Results The total quality control implementation was 117 cases; As a result, 62 quality control material errors were 62 cases, experimental process errors were 24 cases, Kit lot number control errors were 18 cases, and other errors were 13 cases. The quality control material error was corrected and could be used fresh materials within 2 days after thawing. The cases of systemic error were decreased to causes as quality control material error. The quality control materials were reduced above 10 vials to a monthly average. In addition, these errors of experimental processing and Kit lot number were improved by test standardization. Consequently, the cases of 101s and 22s in systematic error rules decreased at least 2 cases to a monthly average. Conclusion To confirm of systematic error through multi-rules application quickly, it is necessary to base on management of the QC material, target values and standard deviation. Moreover, in the event of a systematic error, it was found important to record measures based on test cause analysis. The experiment results are expected to contribute to internal quality control improvement and prompt and accurate result reporting through error recording and causal analysis based on Westgard multi-rules analysis.

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A study on the quality improvement plan of recycled aggregate concrete for the use of building materials (건축자재 활용을 위한 순환골재 콘크리트의 품질개선 방안 연구)

  • Kim, Tae-Hyun;Hong, Sung-In;Choi, Yun-Jeong;An, Jae-Hong
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.162-163
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    • 2022
  • Recycled aggregate has structural limitations in that it cannot be actively used for use as a structural building material due to quality deviations such as increase in cracks, decrease in constructability during in-situ casting, and decrease in strength. Although the government gives incentives to use recycled aggregate concrete for major structural parts of buildings to revitalize recycled aggregate concrete, there is a perception that the quality control of recycled aggregate producers that produce raw materials is insufficient. In this study, recycled aggregate, I checked the quality of the company that handles the quality. We are working on this.

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An Experimental Study for Establishment of On-Site Quality Control of Repair Material by the mechanized construction (기계화시공에 의한 보수재료의 현장품질관리확립을 위한 실험적 연구)

  • Cho Bong Suk;Jang Jae Bong;Kim Yong Ro;Kang Suk Pyo;Hong Sung Yun;Kim Moo Han
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.05a
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    • pp.160-163
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    • 2004
  • In domestic, various repair materials and method systems to keep up with these reinforced concrete deteriorated due to salt damage, carbonation, chemical decay et. developed and applied. However, on-site quality control of various repair materials and method systems isn't achieved desirably because it is depend completely on a men of experience' opinions above all else regardless of various on-site environments. In this background, mock up test with due regard to real on-site environments was performed to secure fundamental data for establishment of desirable on-site quality control. Mock up test using repair mortar analyzed from angles of construction methods, mechanical spraying pressures, W/M. Construction methods were designed manpower method and spraying method, spraying pressures were designed 32, 42, 52 psi, W/M were designed 14.4, 15.4, $16.4\%$. And compressive strength, Chloride ion diffusion coefficient, bond strength, SEM. of mock up test specimens were evaluated. In conclusion, we confirmed excellency of mechanical spraying pressures, fined extremely excellency of condition of spraying pressure 42 ps, W/M $14.4\%$ within this study. therefore the results of this study will be useful to provide fundamental data for establishment of desirable on-site quality control.

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