• 제목/요약/키워드: Primary standard

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Comparison of the Sulfur Dioxide Primary Standard Gases of NPL and KRISS

  • 오상협;김병문;문동민;김진석
    • Bulletin of the Korean Chemical Society
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    • 제22권12호
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    • pp.1341-1344
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    • 2001
  • Comparison of sulfur dioxide primary standard gases of the Korea Research Institute of Standards and Science (KRISS, Korea) and the National Physical Laboratory (NPL, UK) was performed. 100 ${\times}$10-6 mol/mol and 1,000 ${\times}$10-6 mol /mol primary standard gases (designated NPL S115 and S114, respectively) prepared gravimetrically and validated in NPL were used as transfer standards. Transfer standards were analyzed by NDIR sulfur dioxide analyzer and compared with KRISS PSM 112-03-624 and PSM 112-03-625 prepared gravimetrically. Adsorption corrected relative deviations of the primary standard gases were agreed to within 0.1%, and this agreement is within the expanded uncertainties (k = 2) of the primary standards at the two laboratories.

Myringoplasty Outcomes From a 5-Year Single Surgeon's Experience and Important Surgical Technical Aspects

  • Karunaratne, Dilhara;Violaris, Nick
    • Journal of Audiology & Otology
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    • 제25권4호
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    • pp.224-229
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    • 2021
  • Background and Objectives: The United Kingdom (UK) national standard for the closure rate for myringoplasty is 89.5% (90.6% and 84.2% for primary and revision surgeries, respectively). The average hearing gains for primary and revision myringoplasty are 9.14 dB and 7.86 dB, respectively. This study compared the myringoplasty outcomes for a single surgeon over 5 years. Subjects and Methods: Data for 68 cases were analyzed retrospectively. The outcome measures were achievement of the tympanic membrane closure and the average hearing gain or loss. Results: The overall and primary closure rates were 97% and 98%, respectively and significantly higher than the UK national standard (p=0.0210 and p=0.0287, respectively). The revision closure rate was 93%; however, it was not significantly higher than the national standard (p=0.1872). The average hearing gain was 5.18 dB. The gains for primary and revision surgeries were 5.15 dB and 5.25 dB, respectively. Conclusions: We propose that these outcomes are a result of our surgical technique, including the simultaneous use of cortical mastoidectomy in ears with discharge.

Myringoplasty Outcomes From a 5-Year Single Surgeon's Experience and Important Surgical Technical Aspects

  • Karunaratne, Dilhara;Violaris, Nick
    • 대한청각학회지
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    • 제25권4호
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    • pp.224-229
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    • 2021
  • Background and Objectives: The United Kingdom (UK) national standard for the closure rate for myringoplasty is 89.5% (90.6% and 84.2% for primary and revision surgeries, respectively). The average hearing gains for primary and revision myringoplasty are 9.14 dB and 7.86 dB, respectively. This study compared the myringoplasty outcomes for a single surgeon over 5 years. Subjects and Methods: Data for 68 cases were analyzed retrospectively. The outcome measures were achievement of the tympanic membrane closure and the average hearing gain or loss. Results: The overall and primary closure rates were 97% and 98%, respectively and significantly higher than the UK national standard (p=0.0210 and p=0.0287, respectively). The revision closure rate was 93%; however, it was not significantly higher than the national standard (p=0.1872). The average hearing gain was 5.18 dB. The gains for primary and revision surgeries were 5.15 dB and 5.25 dB, respectively. Conclusions: We propose that these outcomes are a result of our surgical technique, including the simultaneous use of cortical mastoidectomy in ears with discharge.

교류전류 1차 표준용 열전형 전류변환기의 제작 (Fabrication of the Thermal Current Converters as the Primary AC Current Standard)

  • 권성원;이래덕
    • 센서학회지
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    • 제1권1호
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    • pp.77-83
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    • 1992
  • 저주파에서의 교류전류 1차표준은 교류-직류 변환기를 이용하여 직류전류표준으로부터 유도된다. 전류측 정범위 $5mA{\sim}20A$, 주파수범위 $10Hz{\sim}100kHz$에서 교류전류의 1차표준기로 사용될 15개의 교류-직류 열전형 전류변환기를 제작 및 평가한 결과, 이를 이용한 교류전류표준의 유지 및 보급의 측정 불확도는, 주파수 20 kHz이 하에서 측정 전류 20 mA까지는 최대 52 ppm, 100 mA까지는 60 ppm으로 확인되었고, 측정 전류 및 주파수가 증가함에 따라 200 ppm까지 증가하는 것으로 나타났다.

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20,000 A 전류변성기 국가표준 시스템 구축 (Establishment of National Standard System for 20.000 A Current Transformer)

  • 정재갑;이상화;강전홍;김명수;김윤형;한상길;한상옥
    • 전기학회논문지P
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    • 제57권1호
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    • pp.6-13
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    • 2008
  • National standard system for calibrating current transformer(CT) up to primary current of 20,000A have been established. The system consists of 20,000 A AC high current source, CT comparator, standard CT, CT under test and CT burden. An AC high current is applied tn the primary windings of both the standard CT and the CT under test, and then the CT comparator measures the ratio error and the phase displacement by comparing the secondary currents of the two transformers. As a validity check for 20,000 A CT calibration system, the comparison with the two national standard institutes(NMIs) has been performed using same CTs. The comparison results of the CTs are consistent with those measured at two NMIs within 0.004 % for ratio error and 0.1 min for phase displacement in the primary current ranges of Ip = 10 - 20,000 A with a secondary current of Is = 5 A.

제로에너지 스쿨을 위한 초등 교육시설의 에너지 성능평가 (Energy Performance Evaluation of A Primary School Building for Zero Energy School)

  • 윤종호;신우철;조진일;박재완;김효중;이철성
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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    • pp.121-126
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    • 2009
  • This study analyzed the standard school's energy usage and patterns as the zero-energy goal of primary school building, and proposed the energy reduction process of school building using energy analysis computing simulation tool. As a analysis simulation tool, Visual DOE 4.0 is used. For analysis of actual energy usage, selected primary school that is standard in the nation's energy consumption. Standard of the school's energy consumption analysis were devided into electric and gas energy. Input parameters of the simulation program based on the literature material and field survey material. after, but it was calibrated to comparison with the standard school's energy consumption. Finally, its energy usage analyzed by component and made the priority order of energy saving. Applied energy saving technologies are envelopment insulation, high efficiency lighting, high performance HAVC system and used active equipment system of solar collector and photovoltaic generation for additional savings.

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색채활용교육의 역량강화를 위한 단계별 표준색표집의 제작 연구 (Manufacture Research of Gradual Standard Color Chart for the Capacity of Reinforcement of Practical Color Coordinate Education)

  • 이경희
    • 한국의류산업학회지
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    • 제13권3호
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    • pp.332-345
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    • 2011
  • This research designed usable standard color chart which was planned by hue and tone color system. This research studied 5 types standard color chart by designed tone map and preceding research. "Basic Color Chart 14 Colors" was planned for kindergarteners. "Primary Color Chart 63 Colors" was planned for schoolboys. "Middle Grade Color Chart 114 Colors" was planned for junior high school students. "High Grade Color Chart 152 Colors" was planned for senior high school students. "Hue and Tone 205 Colors" was planned for university students and general publics. These 5 types standard color chart were produced the trial color coordinate card and attached the Munsell notation which could reappear the spare color paper when needed. These 5 types standard color chart would be offered the data base for efficient color coordinate education as school age.

40,000 A 로고스키 코일 평가 시스템 구축 (Establishment of Evaluation System for 40,000 A Rogowski Coil)

  • 김윤형;한상길;정재갑;강전홍;이상화;한상옥
    • 전기학회논문지P
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    • 제58권2호
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    • pp.202-206
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    • 2009
  • Evaluation system for calibrating Rogowski coiI(RC) up to primary current of 40,000 A have been established. The system consists of 40,000 A AC high current source, current transformer(CT) comparator, standard CT, RC under test, voltage to current convertor(VCC), buffer and CT burden. An AC high current is applied to the primary windings of both the standard CT and the RC under test, and then the CT comparator measures the ratio error and the phase displacement by comparing the secondary current of the standard CT with output current of VCC. For testing of RC, we have evaluated two RCs under test of primary current ranges of 0 A ${\sim}$ 2,000 A and 0 A ${\sim}$ 40,000 A with the accuracy class of 1 %. The extended uncertainty is 0.02 % ${\sim}$ 0.23 % for ratio error and 0.29 min ${\sim}$ 1.93 min for phase displacement in the primary current ranges of 10 ${\sim}$ 40,000 A.

보호복 관련 국내·외 표준에 대한 탐색적 조사 - ISO, ASTM, CEN, KS를 중심으로 - (An Exploratory Study on Domestic and International Protective Clothing Standard - Focused on ISO, ASTM, CEN, KS -)

  • 한설아;남윤자
    • 한국의류산업학회지
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    • 제10권1호
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    • pp.92-100
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    • 2008
  • When designing protective clothing, there are something to be considered such as physiological feature of human body, acting range not to restrict physical activity, and effectiveness of material. Because the primary objective of protective clothing is to protect human body from danger and it is designed through complex designing process not likely general clothing design. However, current evaluation techniques-such as the ISO, the ASTM and the CEN, and KS-provide only the standard to evaluate the primary feature of material (testing, performance requirements, material specification, selection and application, test and care, and so on). There are no standard to evaluate influence for the human body while protective clothing put on. Especially, in Korea, there is KS to evaluate protective clothing, but it is partially translated version from ISO because of lack of core technology about this field. However, developed countries recognize it is new competitive means in the time of Global Standards and they are competing to make their own standard to global standard for the protective clothing. Therefore, it can be great opportunity for Korean clothing and textile industry to revitalize if focusing on research and development for protective clothing design based on physical activity of human body, fit evaluation technique and sizing which is currently no global standard for it and developing our standard to global standard.

Unlined Tunnel 공법 지보재의 설계 및 시공 기준 고찰 (A Study on the Design/construction Standard of Unlined Tunneling Method)

  • 서영화;김성구;나승훈
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.121-134
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    • 2002
  • Tunneling is a very dangerous and expansive work. Especially, the concrete lining works need many long hours and much cost. As an alternative, the unlined tunneling methods including NMT have been developed in various country. These methods have advantages in cost, time and quality. In Korea, many considerations have been conducted to apply the unlined tunneling method in comparatively good rock. Since primary reinforcements play the role of the final supporting system in unlined tunnels, the initial stiffness and long term durability of reinforcements are very important for tunnel safety. To establish the reinforcements standard suitable to Korea, we investigated the foreign standards and construction cases, comparing geological and construction conditions of foreign land and Korea. As the result, we have proposed the standard of primary supporting system for unlined tunnel in aspects of material, design, construction and quality control etc.

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