• 제목/요약/키워드: reference standard

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대형 설비/구조물 안전성에 있어서 국가참조표준의 역할과 전망 (Role and Prospective of Reference Standards for Integrity Controls of Large-scale Structure and Facilities)

  • 남승훈;이윤희;백운봉;정인현;이해무
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.84-89
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    • 2007
  • In order to guarantee the safety of the facility systems, one of the essential components is information on mechanical properties of materials used for the construction. However, acquisition or accumulation of the mechanical property data in industrial fields is limited because this operation does not yield profit, excepting few materials production companies. Corresponding to the urgent needs and poor economical features, the MOCIE has founded the National Center for Standard Reference Data in the KRISS and also designated the Data Center of Mechanical Properties for Metallic Materials (DCMP) as a principal operating section. The DCMP plays roles of collection, edition and evaluation of the mechanical data and development of reference standards. In this study, several functions of the DCMP and standardization procedures of mechanical properties data will be introduced the prospective of standard reference researches will be discussed based on active feedbacks from industrial fields.

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Averaging Current Adjustment Technique for Reducing Pixel Resistance Variation in a Bolometer-Type Uncooled Infrared Image Sensor

  • Kim, Sang-Hwan;Choi, Byoung-Soo;Lee, Jimin;Lee, Junwoo;Park, Jae-Hyoun;Lee, Kyoung-Il;Shin, Jang-Kyoo
    • 센서학회지
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    • 제27권6호
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    • pp.357-361
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    • 2018
  • This paper presents an averaging current adjustment technique for reducing the pixel resistance variation in a bolometer-type uncooled infrared image sensor. Each unit pixel was composed of an active pixel, a reference pixel for the averaging current adjustment technique, and a calibration circuit. The reference pixel was integrated with a polysilicon resistor using a standard complementary metal-oxide-semiconductor (CMOS) process, and the active pixel was applied from outside of the chip. The averaging current adjustment technique was designed by using the reference pixel. The entire circuit was implemented on a chip that was composed of a reference pixel array for the averaging current adjustment technique, a calibration circuit, and readout circuits. The proposed reference pixel array for the averaging current adjustment technique, calibration circuit, and readout circuit were designed and fabricated by a $0.35-{\mu}m$ standard CMOS process.

비표면적 인증표준물질 개발 (Development of Certified Reference Materials for Specific Surface Area)

  • 최병일;김종철;김태영;남현수;권수용
    • 분석과학
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    • 제18권1호
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    • pp.74-84
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    • 2005
  • NT, BT 산업의 발달에 함께 계면에서의 흡착특성의 파악은 신물질의 개발이나 공정의 첨단화에서 꼭 필요한 과제가 되고 있다. 체적식 가스흡착방법은 정량적인 흡착량의 측정이 가능하여 비표면적의 표준측정장비로 인식되고 있다. 상용 비표면적 측정장비의 신뢰성 검증을 위하여 인증표준물질을 개발하였고, SI 단위에 소급성을 유지하는 표준장비에 의해 불확도가 평가되었다. 제작된 인증물질은 비표면적이 $10.72{\pm}0.46m^2g^{-1}$ 인 silicon nitride 분말과 $149.50{\pm}3.44m^2g^{-1}$ 인 alumina 분말이다. 이런 검증된 인증물질의 보급은 산업계에 신뢰성 있는 비표면적 측정결과를 줌으로서, 일관성 있는 공정운용에 의한 품질관리, 생산성 향상, 안정성 판단 및 신제품 개발 등에 기여할 것이다.

Development of reference materials for mortar: Determination of the components and relation with mixing ratio

  • Lim, Dong Kyu;Choi, Myoung Sung
    • Advances in concrete construction
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    • 제10권5호
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    • pp.381-391
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    • 2020
  • This study aimed to develop reference materials (RMs) for mortar that can simulate the initial flow characteristics with constant quality over a long period. Through the previous research on the development of RMs for cement paste, the combination of limestone, glycerol, and water was used as the basic matrix for developing RMs for mortar in this study. In addition, glass beads of three particle sizes (0.5, 1.0, and 2.0 mm) and ISO standard sand were selected as tentative candidates to derive fine aggregate substitutes. The mixture of glass beads could simulate the initial flow characteristics of mortar, but under the same mixing ratio, replicates showed an unstable tendency to indicate inconsistent values due to the generation of electrostatic properties between materials and equipment. On the other hand, the mixture using ISO standard Sand not only simulates the constant flow characteristics for a long period of time, but also shows stable results with little error in replicates. Therefore, limestone, glycerol, ISO standard sand, and water were finally determined as components that met the required properties of RMs for mortar. The effect of each component on the flow characteristics of RMs was analyzed. It was found that glycerol increased the cohesion between the particles of standard sand, resulting in a constant increase both in the plastic viscosity and yield stress. Both limestone and standard sand had a dominant effect on the yield stress. The relationships between various mortar mixing ratios and the corresponding mixing ratios of RMs were established. In addition, the results of the verification experiment showed that the rheological properties of the RMs obtained through the relationships correlated with various water/cement ratios and the fine aggregate volume fractions of mortar obtained with same manner. In other words, the RMs for mortar developed in this study can be used as standard samples because they can simulate the initial flow characteristics of mortar of various mixing ratios for a long period without any chemical changes.

기능성화장품의 기능성평가에 관한 연구(I) -자위선차단화장품의 in vitro 시험법 연구 (Studies on the evaluation of efficacy of functional cosmetics(I) -Studies on the in vitro SPF test method of sunscreen products)

  • 손경훈;김영옥;이정표;양성준;백옥진;김원희;김종갑;허문영;최상숙
    • 대한화장품학회지
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    • 제28권3호
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    • pp.171-184
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    • 2002
  • 인체실험(in vivo) 방법과의 상관성이 우수한 in vitro 자외선차단지수(SPF) 측정방법을 개발하고자 본 연구를 수행하였다. 표준자외선차단제인 8% homomentyl salicyate(HMS) 제제와 P3 reference standard 제제 및 기능성화장품중 자외선차단화장품을 사용하여 자외선차단지수측정기(SPF 290 analyzer)를 가지고 in vitro 자외선차단지수를 측정하고, 인체실험과의 상관계수를 구하였다. 8% HMS 제제 및 P3 Reference standard 제제의 in vitro SPF 결과는 식약청고시 2001-64호의 규정과 유사한 결과를 나타내었고, 크림 및 로오숀 제형에서는 상관계수 0.9506 및 0.9769로서 인체실험과 높은 상관성을 나타내었다. 메이크업베이스 및 리퀴드파운데이션, 사용시 흔들어 쓰는 로오숀, 압축분말은 각각 상관계수 0.8812, 0.8632, 0.5984를 나타내었으며. 압축분말의 도포를 위해서는 크림베이스와 1:0.8의 비율로 섞는 것이 가장 좋은 결과를 나타내었다 본 실험결과를 통해 사람을 이용한 자외선차단지수 측정방법을 대체할 수 있을 것으로 기대되며, 이 후 자외선차단 화장품의 품질관리에 적용하고, 고시개정의 기초자료로 활용될 수 있을 것으로 기대된다.

2017 '한국인 혈당 참조표준'을 이용한 행정구역별 남녀별 공복 혈당 데이터의 특성 및 산포성 비교 (Comparison of Characteristics and Dispersion of Fasting Blood Glucose Data by Administrative Districts and Gender Difference Using the 2017 'Korean Blood Glucose Reference Standard')

  • 권영일
    • 대한임상검사과학회지
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    • 제52권1호
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    • pp.28-35
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    • 2020
  • 본 조사의 목적은 국민건강보험공단에서 공개한 '한국인 혈당 참조 표준'의 원자료를 이용하여 나이 그룹별 95% 분포 상한값과 하한값의 차를 조사하고 이 데이터들에 대한 평균값 변화와 산포 정도를 분석하는 것이다. 그리고 이 데이터를 이용하여 16개 행정구역 간 경향과 남녀간 차이를 분석하는 것이다. 또한 본 조사의 결과가 NHIS에서 제시한 상대표준불화도와 관련성이 있는지를 분석하였다. 본 조사에서 분석한 나이 그룹별 공복혈당의 95% 분포 상한값과 하한값의 차이를 이용한 산포성 분석에서는 행정구역별로 의미 있는 차이와 경향을 보여주었고, 남녀 평균치 간에서도 유의한 차이를 보여주었다(P<0.05). NHIS에서 발표한 공복 혈당 측정값의 남녀간 차이는 행정구역별, 나이그룹별 비교에서 모두 유의한 차이(P<0.001)를 보여 주어 남녀 간 혈당 참고치 재산정 필요성이 인정되었다. NHIS가 발표한 행정구역별 상대표준불확도와 본 조사에서 분석한 산포성 그리고 측정수와는 유의한 상관성이 관찰되지 않았다. 그러나 측정 평균치와는 높은 상관성을 보여주었다(R2=0.95). 또한 참조표준의 적용과 불확도 평가에 대한 추가적인 연구가 필요할 것으로 사료된다.

기준 직물 제시와 비제시 방법에 따른 소모직물의 촉감 평가 비교 (Comparison of the Tactile Sensation of Worsted Fabrics With and Without Reference)

  • 김동옥;김은애
    • 한국의류학회지
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    • 제28권3_4호
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    • pp.452-459
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    • 2004
  • The purpose of this study was to evaluate the effect of reference fabric for the tactile sensation of worsted fabrics. As specimens, 32 worsted fabrics for spring/fall suits were selected. A series of subjective evaluation for roughness, harshness, coarseness, smoothness, warmth, bulkiness and softness were performed with 20 trained panels. The panels were selected by the test of consistency and trained for 3 weeks to enhance the reproducibility and consistency. Subjective evaluation was performed using 9 points Semantic Differential Scales with and without reference fabric. Results showed that the sensations were very similar between the results for the test of with or without reference. However the standard deviations of ratings for the with-reference were much less than that of without-reference which means the use of reference fabric can reduce the subjective error or can reduce the number of panels to test.

클라우드 컴퓨팅에서의 의미 상호운용성을 위한 표준 참조 모델 (A Standard Reference Model for Semantic Interoperability in Cloud Computing)

  • 정동원
    • 한국컴퓨터정보학회논문지
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    • 제17권8호
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    • pp.71-80
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    • 2012
  • 최근 클라우드 컴퓨팅을 위한 많은 표준화 연구가 진행되어 왔으나 데이터 공유 및 교환을 위한 표준 연구는 거의 이루어지지 않았다. 무엇보다 해당 표준화 기구에서는 의미 상호운용성 향상을 위한 구체적인 표준화 항목 및 참조 모델을 제시하고 있지 않다. 이 논문에서는 현재까지의 표준화 문제점을 정의하고, 의미 상호운용성 제공을 위한 구체적인 표준화 항목 및 참조 모델을 제안한다. 이를 위해 먼저 클라우드 컴퓨팅을 위한 전반적인 표준화 동향을 분석하고, 특히 데이터의 의미적 상호운용성을 제공을 위한 표준 개발 현황을 기술한다. 또한 다양한 분야의 표준개발에 이용된 데이터 교환 및 관리 분야의 표준 개념을 기반으로 잠재적인 표준화 항목을 정의한다. 마지막으로, 표준화 항목 간의관계성과 전체적인 의미 상호운용성 과정을 보여주기 위해 참조 모델을 기술한다. 이 논문은 표준 개발을 위한 가이드라인으로서 이용될 수 있으며, 아울러 클라우드 컴퓨팅의 표준화를 촉진할 수 있다.

Characterizing a Full Spectrum of Physico-Chemical Properties of Ginsenosides Rb1 and Rg1 to Be Proposed as Standard Reference Materials

  • Kim, Il-Woung;Hong, Hee-Do;Choi, Sang-Yoon;Hwang, Da-Hye;Her, Youl;Kim, Si-Kwan
    • Journal of Ginseng Research
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    • 제35권4호
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    • pp.487-496
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    • 2011
  • Good manufacturing practice (GMP)-based quality control is an integral component of the common technical document, a formal documentation process for applying a marketing authorization holder to those countries where ginseng is classified as a medicine. In addition, authentication of the physico-chemical properties of ginsenoside reference materials, and qualitative and quantitative batch analytical data based on validated analytical procedures are prerequisites for certifying GMP. Therefore, the aim of this study was to propose an authentication process for isolated ginsenosides $Rb_1$ and $Rg_1$ as reference materials (RM) and for these compounds to be designated as RMs for ginseng preparations throughout the world. Ginsenoside $Rb_1$ and $Rg_1$ were isolated by Diaion HP-20 adsorption chromatography, silica gel flash chromatography, recrystallization, and preparative HPLC. HPLC fractions corresponding to those two ginsenosides were recrystallized in appropriate solvents for the analysis of physico-chemical properties. Documentation of the isolated ginsenosides was made according to the method proposed by Gaedcke and Steinhoff. The ginsenosides were subjected to analyses of their general characteristics, identification, purity, content quantitation, and mass balance tests. The isolated ginsenosides were proven to be a single compound when analyzed by three different HPLC systems. Also, the water content was found to be 0.940% for $Rb_1$ and 0.485% for $Rg_1$, meaning that the net mass balance for ginsenoside $Rb_1$ and $Rg_1$ were 99.060% and 99.515%, respectively. From these results, we could assess and propose a full spectrum of physicochemical properties for the ginsenosides $Rb_1$ and $Rg_1$ as standard reference materials for GMP-based quality control.

히스토그램 변환에서 기준분포의 표준편차 변경에 따른 강인한 화자인증 성능 개선 (Performance Improvement of Robust Speaker Verification According to Various Standard Deviations of a Reference Distribution in Histogram Transformation)

  • 권철홍
    • 말소리와 음성과학
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    • 제2권3호
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    • pp.127-134
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    • 2010
  • Additive noise and channel mismatch strongly degrade the performance of speaker verification systems, as they distort the features of speech. In this paper a histogram transformation technique is presented to improve the robustness of text-independent speaker verification systems. The technique transforms the features extracted from speech such that their histogram is conformed to a reference distribution. The effect of different standard deviations for the reference distribution is investigated. Experimental results indicate that, in channel mismatched environments, the proposed technique offers significant improvements over existing techniques. We also verify performance improvement of the proposed method using statistics.

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