• 제목/요약/키워드: Material Standards

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Leakage-reduction Measures at a Joint between CPVC Piping for a Sprinkler System and a Pipe Expansion (스프링클러설비용 CPVC관과 신축배관 접속부분에서의 누수저감 대책에 관한 연구)

  • Lim, Chun-Ki;Lim, Yun-Tack;Baek, Eun-Sun
    • Fire Science and Engineering
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    • v.29 no.3
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    • pp.21-30
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    • 2015
  • In this study, we try to suggest measures to reduce leakage at a joint between CPVC piping for a sprinkler system and a pipe expansion through reviews of domestic and foreign standards and related tests. The quality of the waterproof rubber packing material between a valve socket and pipe expansion nut was examined. In the leak test, the valve socket material over the expansion part of the metal pipe nut was found to use a metal part or a schlorinated polyvinyl chloride pipe nut part. In addition, the KS B 0221 standard for parallel pipe threads with threaded and thread inspection criteria and inspection standards in order to ensure an acceptable quality of valve socket, there is a need to amend the regulations to comply with the KS B 5223 (screw thread limit gauges parallel pipe threads). We do not have detailed standards for expansion piping nuts for waterproof rubber ring material, so we need to amend the relevant criteria for EPDM material to be used with excellent waterproofing, for which both NBR and EPDM are currently used.

Development and Properties of Carbon monoxide Detector for Ambient Air monitoring (대기오염 측정용 일신화 탄소 검출기의 제작 및 특성)

  • Cho, Kyung-Haeng;Lee, Sang-Wha;Lee, Joung-Hae;Choi, Kyong-Sik
    • Analytical Science and Technology
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    • v.13 no.2
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    • pp.222-228
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    • 2000
  • A detector for monitoring carbon monoxide (CO) in ambient air by nondispersive infrared (NDIR) spectroscopy has been developed and investigated its sensitivity and stability. The essential parts of the absorption cell are three spherical concave mirrors so as to improve the sensitivity by increasing the light path length in the cell. The radius and center of curvature of mirrors and position in the cell was calculated by computer simulation in order that the light path length may be 16m into the 50cm cell. The number of traversals and optical path properties were confirmed by laser beam alignment in transparent absorption cell. The photoconductive type lead selenide (PbSe) was used as CO sensing material, which was cooled to increase the responsibility by thermoelectric cooling method. The detection limit and span drift of the developed CO detector was 0.24ppm and 0.03ppm(v/v) respectively.

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A study for biocompatibility of acupuncture's metal material - Focused on chemical composition and mechanical character - (침 금속재료에 대한 생체적합성 연구 - 화학적 조성 및 기계적 특성을 중심으로 -)

  • Baek, Yong-hyeon;Chung, In-tae;Lee, Sang-hun;Lee, Jae-dong;Choi, Do-young
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.159-176
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    • 2004
  • Objective : To present a criteria for acupuncture standardization, which will improve quality of acupuncture and secure safety, through studies of the biocompatibility of acupuncture. Methods : The acupunctures distributed in Korea were studied. The chemical composition, elasticity, and the solidity of the acupuncture's metal material was analyzed. Results & Conclusions : 1) The acupunctures distributed in Korea were all produced with ST304. Because acupuncture is used on a living body, the corrosion resistance, allergy proof and magnetism of the metal material should be considered. In this point, STS316 stainless steel would be more suitable than ST304. 2) The elasticity and solidity of the acupuncture's metal material distributed in Korea meet the medical instrument standards of the Korea Food and Drug Administration. But since the standards are only roughly outlined, the criteria should be realized and standardized.

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A Study on the Corrosion Properties of Reinforcing bar and Performance Evaluation of Repair Material and Method for Reinforced Concrete Structure by Exposure Experiment under the Coastal and Normal Atmosphere Environment (해양 및 일반대기환경의 폭로실험에 의한 철근콘크리트구조물 보수재료.공법의 성능평가 및 철근의 부식특성에 관한 연구)

  • Nam Jeong-Soo;Roh Kyung-Min;Shin Seung-Bong;Kim Young-Sun;kim Gyu-Yong;Kim Moo-Han
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.05a
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    • pp.167-171
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    • 2006
  • In this study, for the establishment of the performance evaluation methods of repair material and method for reinforced concrete structure and the quality control standards of durability recovery method, the quantitative exposure data by exposure experiment under the coastal and normal atmosphere environment is accumulated and analyzed. Investigating and evaluating the result of exposure experiment during 30 months of exposure age under the coastal and normal atmosphere environment, carbonation depth and chlorideion penetration depth very little penetrated than cover depth. It seems reasonable to conclude that main cause of corrosion of reinforcing bar are inner chloride-ion and macro cell from the result of corrosion area and corrosion velocity. Accordingly, it is considered that fundamental data on the performance evaluation and quality control standards of repair material and method could be presented through continuous exposure test in the future.

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The Time Series Analysis of Standards and Results of Nutritional Domain in Hospital Evaluation Program (의료기관 평가제도 영양부문 기준 및 결과의 시계열 변화 분석)

  • Lee, Joo-Eun
    • Journal of the Korean Dietetic Association
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    • v.19 no.4
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    • pp.317-342
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    • 2013
  • The purpose of this study was to evaluate the current state of foodservice and clinical nutrition management in a hospital-based nutrition department. Nutritional guidelines and survey reports of hospital evaluation programs from 2004 to 2009 were analyzed. In total, 275 hospitals in the first period and 288 hospitals in the second period were evaluated. The division of knife and chopping board use decreased from 97.2% in 2005 to 89.7% in 2008, the maintenance of a proper freezer temperature (below $-18^{\circ}C$) increased from 82.1% in 2004 to 97.7% in 2007 (88.9% to 97.4% from large hospitals and 69.8% to 86.5% from small/medium hospitals in 2005 and 2008, respectively). In tube-feeding management, the performance rate of material cold storage and the offer rate of tube-feeding were 65.9% and 94.2% in 2007, respectively. The cold storage of material, proper use within 24 hours after opening or production, and the use of an appropriate label were 47.3%, 71.2% and 67.2% in 2009, respectively. The rate of a management system for undernourished patients was 86.0% in 2007 (56.4% for large hospitals, 18.9% for small/medium hospitals) and 14.3% in 2009. In standards of nutrition support management, the performance rates of constructing a nutrition support team, the nutrition support team activity, and organizing multidisciplinary team were 66.7%, 43.6%, and 64.1% respectively, in 2004. For large hospitals, those rates were 61.1%, 36.1%, and 58.3%, in 2005, 93.0%, 62.8%, and 91.9% in 2007, and 69.2%, 43.6%, and 69.2% in 2008, respectively. The results of this study suggest standards on sanitary foodservice preparation, production, and tube-feeding production need to correspond with HACCP regulations for small/meidium hospitals in standards of a healthcare accreditation system. It will be necessary to understand the operating conditions of nutrition departments in convalescent hospitals, psychiatric hospitals, and geriatrics hospitals. As the application of accreditation is required from 2013, standards will need to be improved and continuously updated for healthcare accreditation.

Standardization of Construction Materials in Plumbing and Drainage Facilities (급배수 위생설비공사 건설자재의 표준화)

  • Cho, Chung-Sik;Kim, Sun-Sookk;Kim, Jin
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.485-490
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    • 2009
  • The present study has been conducted to accomplish the investment and analysis, to make the construction manuals, to draw the standards, and to build quality and standards informations of the plumbing/drainage facilities materials. The application plan and the anticipation effect of this results include as follows. (1) The investment and analysis of the plumbing/drainage facilities materials is able to suggest the technology trends and the trends analysis in the construction materials. (2) The quality and standards informations of the plumbing/drainage facilities materials are possible to be the construction faculty and the cost/energy reduction in the construction materials. (3) The standards methods of the plumbing/drainage facilities materials are useful for the reliability guarantee and quality escalation in the construction materials. (4) The standard manuals of the plumbing/drainage facilities materials are applied to the specifications in the construction materials.

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The Standard in family resource management: Diagnosis and future direction (가정관리에서의 생활표준 : 진단과 과제)

  • 이연숙
    • Journal of Family Resource Management and Policy Review
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    • v.2 no.2
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    • pp.39-51
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    • 1998
  • The purpose of this study were to clarify the concepts, origin, and roles of standard, to diagnose the standard developed in contemporary family living, and to suggest desirable standard for effective home management. Five prevalent standards found in managing family resources were convenient-oriented standard, others-oriented standard, material-oriented standard, individual-oriented standard, and frugal-oriented standard. The changes of social and cultural environments and family resources affecting these standards and some problems resulted from these were discussed. Considering undesirable effect of old standards on resource management, family relationship, quality of life, and society in general, these old standards should be replaced by compromise convenient-oriented standard, self-oriented standard, being-oriented, joint-oriented standard, and new frugal-oriented standard. Some recommendations for future research, publicity, and policy were suggested.

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Analysis on Transition between Index- and Bandgap-guided Modes in Photonic Crystal Fiber

  • Hong, Kee Suk;Lim, Sun Do;Park, Hee Su;Kim, Seung Kwan
    • Journal of the Optical Society of Korea
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    • v.20 no.6
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    • pp.733-738
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    • 2016
  • We calculate optical properties of guided modes of a hybrid-guiding photonic crystal fiber. The design and modeling of such hybrid-guiding PCF is made by replacing air holes with inserts of high refractive index material layer by layer in order. The optical properties such as mode intensity profile, mode dispersion, optical birefringence, confinement loss, and chromatic dispersion during transition of the guiding mechanism are analyzed and discussed. The guided modes in the hybrid-guiding region are also compared with those of reference index-guiding and bandgap-guiding photonic crystal fibers.

Determination of trace elements in food reference materials by instrumental neutron activation analysis

  • Cho, K.H.;Zeisler, R.;Park, K.W.
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.520-528
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    • 2005
  • Two biological Certified Reference Materials (CRMs), KRISS 108-04-001 (oyster tissue) and 108-05-001 (water dropwort stem), were prepared by Korea Research Institute of Standards and Science (KRISS)during FY '01. The certified values of these materials had been determined by Isotope Dilution Mass Spectrometry (IDMS) for six elements (Cd, Cr, Cu, Fe, Pb and Zn). Additional analytical works are now progressing to certify the concentrations of a number of the environmental and nutrimental elements in these CRMs. The certified values in a CRM are usually determined by using a single primary method with confirmation by other method(s) or using two independent critically-evaluated methods. Instrumental Neutron Activation Analysis (INAA) plays an important role in the determination of certified values as it can eliminate the possibility of common error sources resulting from sample dissolution. In this study INAA procedure was used in determination of 23 elements in these two biological CRMs to acquire the concentration information and the results were compared with KRISS certified values.

Confirmation of reference value using uncertainty of multiple measurements (반복측정의 불확도를 이용한 인증값 확인)

  • Choi, Jong-Oh;So, Hun-Young;Woo, Jin-Chun;Hwang, Eui-Jin
    • Analytical Science and Technology
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    • v.15 no.6
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    • pp.580-583
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    • 2002
  • New approach is developed employing the overall uncertainty obtained from multiple measurements to evaluate the statistical significance for the difference between a given reference value and its measured value determined in a lab. The overall uncertainty is determined by separate combinations of the uncertainties arising from systematic and random effects. It is shown that the uncertainty term in regular t-test can be underestimated by n measurements.