• Title/Summary/Keyword: Natural Standard

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Evaluation of Stress-Strain Characteristics of Weldment in Natural Gas Pipeline Using Advanced Indentation System (Advanced Indentation System을 이용한 천연가스배관 용접열영향부의 응력-변형률 변화 특성 분석)

  • Jang, Jae-Il;Son, Dong-Il;Kwon, Dong-Il;Kim, Woo-Sik;Park, Joo-Seung
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.483-488
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    • 2001
  • Until now, the tensile properties of materials can be obtained just in accordance with conventional tensile testing methods which are described in several standards such as ASTM (American Society for Testing and Materials) standard and BS (British Standard). For some cases including on-service facility materials, however, the standard testing methods cannot be applicable due to the destructive testing procedure and specimen size requirement. Therefore, simple, non-destructive and advanced indentation technique was proposed. This test measures indentation load-depth curve during indentation and analyzes the mechanical properties related to deformation and fracture. In this paper, the research trend of non-destructive evaluation of tensile properties using AIS (advanced indentation system) and its application fields are reviewed and discussed.

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Similarity Analysis of Chemical Profiles of Scrophularia buergeriana Based on HPLC-DAD

  • Kim, Dae-Hyun;Park, Jin-Ho;Kim, Young-Choong;Sung, Sang-Hyun;Kim, Seung-Hyun
    • Natural Product Sciences
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    • v.17 no.3
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    • pp.225-229
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    • 2011
  • A new approach for similarity analysis of chemical profiles of Scrophularia buergeriana was developed. The roots of S. buergeriana collected in Andong, Korea were analyzed using HPLC-DAD and the peak areas of the chromatograms were used to construct the chemical profiles of S. buergeriana. The analytical conditions were validated for specificity, precision and repeatability. The standard chemical profiles were established from the chromatograms of nine standard analytical extracts from three batches. The correlation coefficients of peak areas of characteristic compounds between the chromatograms of the standard and test samples were calculated for quantitative expression of the chemical profiles. The results showed that the HPLC chemical profiles of the samples of same geographic origin were relatively consistent. This new approach could be applied to the quality assessment of herbal medicines with complex chemical compositions.

Solution for the Improvement in Structural Design & Application of PEB System for the Standard Livestock Housing(2008) (표준축사 모델에서 PEB시스템의 적용 및 구조설계 개선방안)

  • Park, Man-Woo;Do, Byung-Ho;Song, Jun-Ik
    • Journal of Animal Environmental Science
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    • v.15 no.1
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    • pp.17-28
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    • 2009
  • PEB system is more economical when compared with structures commonly used Hot rolled and welded light H-beam was introduced in the Standard Livestock Housing. This study suggested more economical technology for structural design by the reduction of live load, relief of deflection limit and reduction of importance factor. And, when applying wind Load as a result of examination with Low Rise Building Systems Manual considering open model, we can know that when the wind load is big, enclosed model is more stable than open model. In short, Suggesting more economical model and providing the method to reduce natural disaster, by the application of PEB system and the development of technology for structural design, are considered to strengthen the competitive power of farmhouse.

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FISSION PRODUCT RELEASE ASSESSMENT FOR END FITTING FAILURE IN CANDU REACTOR LOADED WITH CANFLEX-NU FUEL BUNDLES

  • Oh, Dirk-Joo;Jeong, Chang-Joon;Lee, Kang-Moon;Suk, Ho-Chun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.651-656
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    • 1997
  • Fission product release (FPR) assessment for End Fitting Failure (EFF) in CANDU reactor loaded with CANFLEX-natural uranium (NU) fuel bundles has been peformed. The predicted results are compared with those for the reactor loaded with standard 37-element bundles. The total channel I-131 release at the end of transient for EFF accident is calculated to be 380.8 TBq and 602.9 TBq for the CANFLEX bundle and standard bundle channel cases, respectively. They are 4.9% and 7.9% of the total inventory, respectively. The lower total releases of the CANFLEX bundle O6 channel are attributed to the lower initial fuel temperatures caused by the lower linear element power of the CANFLEX bundle compared with the standard bundle.

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Development of the Certification Standard of the Occupational Safety & Health Management System for Small & Medium Enterprises (중소규모 사업장용 안전보건경영시스템 인증기준 개발)

  • Jang, Seo-Il;Ha, Jeong-Ho;Lyu, Bo-Hyuk;Kim, Tae-Ok
    • Journal of the Korea Safety Management & Science
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    • v.10 no.4
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    • pp.11-20
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    • 2008
  • The present management of the domestic and international advanced enterprises is transferring the systems and the regulations to the prevention system management. Expecially, KOSHA (Korea Occupational Safety & Health Agency) in Korea has supported to set up the OSHMS (Occupational Safety & Health Management System) by KOSHA 18001 since 1997. But small & medium enterprises (SMS) have many difficulties to set up the OSHMS because of limited natural and human resources. Therefore, this study is developed and proposed the certification standard of an OSHMS for SMS based on the case study on advanced countries, actual conditions of SMS in Korea, and opinion of specialists.

A Study on Performance Standards of Quality Improvements of Self-adhesive Waterproofing Sheets by Materials (계열별 자착형 방수시트의 성능 품질기준 개선안에 관한 연구)

  • Park, Jin-Sang;Jeon, Jong-Su;Song, Je-Young;Bae, Kee-Sun;Oh, Sang-keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.303-304
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    • 2013
  • The field application through the quality control of self adhesive rubberized asphalt waterproofing sheet was regulated by KS F 4934 of Korea Standard in 2003. However, the regulations that the different material properties of self-Adhesive waterproofing sheets are difficult to quality control on the standard. Therefore, this research was performed for of quality control all affiliations of self-adhesive waterproofing sheet through basic properties test and proposed quality standard revised bill in KS F 4934.

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Analysis of Standard and FLIP Fuel Mixed Loading Patterns in TRIGA Mark-III Reactor

  • Kim, Jung-Do;Lee, Jong-Tai;Yook, Chong-Chul
    • Nuclear Engineering and Technology
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    • v.11 no.4
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    • pp.287-293
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    • 1979
  • Mixed standard-FLIP fuel loading patterns in the TRIGA Mark-III reactor were analyzed. It was judged that the mixed loading pattern with the standard fuel in the B-ring and the FLIP fuel in other rings was mostly desirable in view of fuel temperature, cooling condition with the natural convection, or effective thermal flux utilization in the central thimble. In addition, tile maximum useful flux in tile reactor beamports versus the loading patterns was evaluated.

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Ideal Classes and Cappell-Shaneson Homotopy 4-Spheres

  • Min Hoon Kim;Shohei Yamada
    • Kyungpook Mathematical Journal
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    • v.63 no.3
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    • pp.373-411
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    • 2023
  • Gompf proposed a conjecture on Cappell-Shaneson matrices whose affirmative answer implies that all Cappell-Shaneson homotopy 4-spheres are diffeomorphic to the standard 4-sphere. We study Gompf conjecture on Cappell-Shaneson matrices using various algebraic number theoretic techniques. We find a hidden symmetry between trace n Cappell-Shaneson matrices and trace 5 - n Cappell-Shaneson matrices which was suggested by Gompf experimentally. Using this symmetry, we prove that Gompf conjecture for the trace n case is equivalent to the trace 5 - n case. We confirm Gompf conjecture for the special cases that -64 ≤ trace ≤ 69 and corresponding Cappell-Shaneson homotopy 4-spheres are diffeomorphic to the standard 4-sphere. We also give a new infinite family of Cappell-Shaneson spheres which are diffeomorphic to the standard 4-sphere.

Antioxidant activities of Pu-erh tea (보이차(Pu-erh tea)의 항산화 효과)

  • So, Eun Mee;Jung, Eun Joo;Shin, Chang Chul;Kim, Sung Hyun;Baek, Soon Ok;Kim, Young Man;Kim, Il Kwang
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.39-44
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    • 2006
  • Puh-erh tea was extracted with water and then fractionated sequentially with n-hexane, ethyl acetate, n-butanol to find antioxidative compounds. The fractions were examined on the antioxidant activity using two different methods, free radical scavenging activity measurement and reductive potential. Those antioxidant activities were compared to standard antioxidants such as butylated hydroxyanisole(BHA), butylated hydroxytoluene (BHT), and ${\alpha}$-tocopherol. EA fraction of Pu-erh tea was showed excellent antioxidative activities over BHA and BHT.

Experimental Study on the Flame Stable Region of Natural Gases from Various Producing Districts (산지별 천연가스의 화염 안정영역에 관한 실험적 연구)

  • Lee, Chang-Eon;Hong, Sung-Chang;Jeong, Young-Sik;You, Hyun-Seok;Lee, Seung-Jun;Her, Jae-Young;Hwang, Cheol-Hong
    • 한국연소학회:학술대회논문집
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    • 2007.05a
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    • pp.69-75
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    • 2007
  • In this study, the difference of flame stability zone for natural gases from producing districts was studied experimentally using a new type of flame stability diagram. The similarity of stable flame zone between a domestic appliance and an interchangeability test(IT) burner is also examined. As a result, the stable flame zones expressed by limits curves of flame lifting and yellow tipping show the similar results in a domestic gas range and IT burner. Furthermore, IT burner can reproduce the flash back phenomena and show the distinct difference of fuel type as the burner diameter is increased. To suggest the new type of flame stability diagram in the respect of fuel interchangeability, the air flowrate and Wobbe fuel flowrate were adopted as axis coordinates. It can be identified that the new diagram can provide the useful information on the difference of flame stability zone, heat input rate and air-fuel ratio when a fuel is altered to other fuels under the identical operating conditions. Finally, the stable flame zones for natural gas of 6 type are compared, and the detailed information to use as the interchangeability fuels of standard natural gas is provided using the new type of flame stability diagram.

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