• Title/Summary/Keyword: Evaluation Standards

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Uncertainty Evaluation of Josephson Voltage Standard in the level of $10^{-10}$ (10의 -10승 수준에서 조셉슨 전압표준기 불확도 평가)

  • Kim, K.T.;Kim, M.S.;Chong, Y.;Kim, W.S.;Song, W.
    • Progress in Superconductivity
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    • v.9 no.1
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    • pp.56-61
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    • 2007
  • The most recent improvement in the 10 V array system was carried out with focusing on noise reduction. We have evaluated the uncertainty of the 10 V Josephson array system after the improvement. The uncertainty evaluation of 10 V standard included a comparison with a programmable Josephson array system at 1 V. Every contribution to the measurement uncertainty was evaluated in the level of $10^{-10}$. The estimated combined uncertainty was found to be approximately $10^{-9}$ at 10 V, which was limited only by the indirect verifying method. In the near future, a direct comparison with another 10 V Josephson voltage standard is expected to be carried out to provide more accurate uncertainty evaluation for the KRISS Josephson voltage standard.

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A Study on the Efficiency Evaluation Standard and Regulation for Electric Motor Systems (전동기 시스템의 효율 평가 규격 및 규제 현황 연구)

  • Jun, Hee-Deuk;Park, Han-Seok;Kim, Dea-Kyong;Woo, Kyung-Il
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.9
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    • pp.1618-1625
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    • 2016
  • Electric motor systems account for more than half of all electric systems and the amount of energy consumption of those is almost 70 percent of total energy consumption of electric motor systems in industry. As electric motor systems are very responsible for global electricity savings and environment protection. Many international organizations are supporting standards and policy development processes to improve the efficiency of electric motor systems. Many standards are being developed at technical committee of IEC that has been required in order to support the implementation of efficiency regulations. High efficiency standards and levels for electric motor systems are slowly being introduced and compulsory in many countries. Therefore understanding the international efficiency evaluation standards and the regulation of electric motor systems of each country is important. This paper presents the current status and trends of international evaluation standards and regulations about the efficiency of electric motor systems.

An Overview on Standards for Seasonal Performance Evaluation of Multi-type Air Conditioners (멀티형 에어컨의 기간에너지소비효율 평가규격에 관한 연구)

  • 박윤철;문제명;홍주태
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.1
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    • pp.91-100
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    • 2004
  • Energy efficiency evaluation method for a multi-type air conditioning system still has not been developed. In this study, analysis on capacity range and evaluating method of standards for air conditioners was conducted with world-wide Standards. It is not a proper approach to use the standards for residential air conditioner to multi type air conditioners. Some difficulties and problems are commented in this study with overview of the standards. Through the analytic research, an evaluating method for multi type air conditioner was suggested with Integrated Part Load Value (IPLV). The suggested concept for evaluating energy efficiency during part load condition considers building load pattern and operating hours of the system at different locations. Load was weighted in IPLV to consider not only the concept of occurrence of outdoor temperature such as bin method but also operation hours of the system. An experiment about the IPLV was conducted with variable air volume ducted type air conditioning system and multi-type system through modified code tester to give a glance at quantitative value of the IPLV.

Development of dimethyl sulfide gas CRM and stability test (다이메틸설파이드 가스 인증표준물질 개발 및 안정성 평가)

  • Kim, Young-Doo;Heo, Gwi-Suk;Oh, Sang-Hyub;Kim, Byoung-Moon;Bae, Hyun-Kil;Woo, Jin-Chun
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.552-558
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    • 2005
  • A type of dimethyl sulfide gas CRM in the ppb level was developed for the analysis of trace-level odorous gas in environmental atmosphere. The concentration of dimethyl sulfide ($(CH_3)_2S$) was 10 umol/mol level in the cylinder filled with nitrogen, 1500 psi. And the variability of the concentration for 3 years was about 0.1% due to the adsorption or instability of $(CH_3)_2S$. The gas standards produced simultaneously in 4 bottles and examined by GC-FID were shown with 0.4%, reproducibility of preparation and 0.25%, standard uncertainty due to weighing and purity. The relative expended uncertainty of 1.1% (95% of confidence level, k=2) was assigned to the certified value of 10 umol/mol level of $(CH_3)_2S$ after quantitative evaluation on the purity, mixing, weighing, analysis, adsorption and stability of dimethyl sulfide gas.

Determination of Ni, Cr, Mo in Low Alloy Steel Reference Materials by Isotope Dilution Inductively Coupled Plasma Mass Spectrometry (동위원소희석 유도결합플라스마질량분석법에 의한 저 합금강 표준시료중의 Ni, Cr, Mo의 분석)

  • Suh, Jungkee;Woo, Jinchoon;Min, Hyungsik;Yim, Myeongcheul
    • Analytical Science and Technology
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    • v.16 no.1
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    • pp.82-89
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    • 2003
  • Isotope dilution mass spectrometry (IDMS) was applied to the determination of Ni, Cr, Mo in low alloy steel reference materials. The Mo isotope ratio measurement was performed by dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP/MS) using ammonia as a reaction cell gas. In the case of Ni and Cr measurement, all data were obtained at medium resolution mode (m/${\Delta}m=3000$) of double focusing sector field high resolution inductively coupled plasma mass spectrometry (HR-ICP/MS). For the method validation of the technique was assessed using the certified reference materials such as NIST SRM 361, NIST SRM 362, NIST SRM 363, NIST SRM 364, NIST SRM 36b. This method was applied to the determination of Ni, Cr and Mo in low alloy steel sample (CCQM-P25) provided by NMIJ for international comparison study.

A Study on Standards for Performance Evaluation of Biometric Recognition Systems (국내 생체 인식 시스템 성능 평가를 위한 표준안 연구)

  • 문지현;김학일
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.12 no.2
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    • pp.101-110
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    • 2002
  • The purpose of this research is to establish Korean standards of best practice and common criteria for testing and evaluating the performance of biometric recognition systems. First of all, research activities in leading countries such as USA, Great Britain and Germany have been studied and analyzed. Then, the standards of best practice and common criteria are proposed in the aspects of sensors, algorithms, and application systems. The results of this work will be utilized fur test and evaluation of commercial biometric products by KISA and provided to private industries for their own evaluation of products.

A Proposal Research of Assessment Standards for Ordering BIM-based Projects in Railway Infrastructure - Case Study on Application of Existing Projects - (철도인프라 BIM기반 공사 발주를 위한 평가기준 제안 연구 - 기존 발주사업 적용 사례를 통해 -)

  • Son, Seo-Yeon;Lee, Geun-Il;Jung, Ji-Hyun;Moon, Woo-Hyoung
    • Journal of KIBIM
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    • v.11 no.4
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    • pp.10-19
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    • 2021
  • In the evaluation for ordering BIM-based projects (Design Build) of Korean National Railway, criteria of BIM-based smart construction technology are assessed. Unlike the existing assessment criteria, performance resources and detailed assessment guidelines have been added by this research. The purpose of this study is to propose qualification assessment standards according to specific guidelines when evaluating on the phase of bidding for BIM-based projects. In the study, an improved evaluation standard (draft) was arranged based on two consultation meetings and surveys of related companies, applied to existing projects with the companies that won the bid, and validated. As more specific and added criteria compared to the existing standards, it could reduce the difficulty of evaluation for BIM capability and lay the foundation for railway BIM-based project management.

Revision and catagorization of evaluation criteria for state change factors in agricultural reservoirs

  • Jae Woong Shim;Young Hak Lee;Dal Won Lee
    • Korean Journal of Agricultural Science
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    • v.49 no.4
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    • pp.707-717
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    • 2022
  • As the variability of recent rainfall is increasing, it is becoming important to recognize the possibility of changes in the current reservoir state in advance and to inspect the stability based on accurate evaluation standards. However, the evaluation standards for the state change factors of reservoirs are still not suitable for agricultural reservoirs and thus much improvement is needed. Therefore, in this study, the evaluation criteria for state change factors specialized for small reservoirs were categorized and standards were prepared by considering factors that may cause state changes on the dam crest, upstream slope, and downstream slope of the embankment. The categorized results were configured based on the number of mentions of the precision safety inspection report on major defects in 102 reservoirs and the defect factors found in field investigations. The findings of the study indicated that the current state change standards require many revisions for excessive or unnecessary state change factors in the reservoir. Specifically, the deletion of measurement gauges not applicable to the reservoir, the addition of defects found in the reservoir, and the scope of use of the term were proposed. The results of this study can contribute to efficient system operation and management by improving the deficiencies in the system and introducing a new state change factor.

A Study on the Development of Environmental Indicators and the Evaluation of Environmental Amenity (쾌적환경평가 및 지표개발에 관한 연구 - 경기도를 중심으로 -)

  • 성현찬;이영준
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.4
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    • pp.23-38
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    • 1997
  • In this Study, indicators for the evaluation of environmental amenity were determined through the investigation of the resident's consciousness in all thirty one cities and counties of Kyonggi. Also, environmental amenity that the resident feel in terms of recognition level was evaluated and based on the determined environmental indicators, environmental amenity for the physical environmental situation was evaluated. By analyzing the results, basic data for the planning of the future environmental management were prepared. The results of this study can be summarized as follows First, the developed indicators for the evaluation of environmental amenity consist of four intermediate evaluation items and fifteen individual evaluation items, and fifty four evaluation standards in total . Two to five evaluation standards were determined for the respective individual evaluation items. Second, using the developed indicators, the evaluation of environmental amenity were implemented based on both resident's consciousness and statistical data. Third, by analyzing the difference between two evaluation results, future research plan was proposed.

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