• Title/Summary/Keyword: science standard

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A Comparative Study on the Ambient Air Quality Standard Strength among Korea, the U.S.A. and the EU (우리나라, 미국 및 유럽의 대기환경기준 강도에 관한 비교 연구)

  • Park, Min-Bin;Lee, Tae-Jung;Lee, Eun-Sun;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.6
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    • pp.559-574
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    • 2016
  • Based on air quality monitoring data ('10~'14) of Suwon City provided by the Korean Department of Environment, a fundamental statistic for 5 criteria pollutants such as $SO_2$, CO, $NO_2$, $O_3$, and $PM_{10}$ was initially investigated. The purpose of this paper was to review the ambient air quality standards(AAQS) of Korea, the U.S.A. and the EU and further to assess the degree of standard strength by the achievability of the AAQS comparing each national standard. Since the level and the way of standards for each air pollutant are various among countries, it is difficult to determine the degree of relative attainment using the same set of data above. Further when all the areas having bad air quality for a specific pollutant are classified as non-attainment case, it is more difficult to assess the degree of standard strength. Thus we introduced a new concept called the average concentration distance (ACD) to quantitatively estimate the strength. As results, the Korean 1-hr $NO_2$ AAQS is slightly stronger than the US standard and weaker than the EU standard. The Korean $O_3$ standard is strongest; however, the Korean $PM_{10}$ standard is weakest. Furthermore the equivalent levels of 8-hr $O_3$ standards in the U.S.A. and the EU were respectively estimated as 97.5 and 95.7 percentiles of the Korean standard with maintaining the existing standard of 60 ppb.

Accurate Measurement of Arsenic in Laver by Gravimetric Standard Addition Method Combined with High Resolution Inductively Coupled Plasma Mass Spectrometry

  • Lee, Kyoung-Seok;Kim, Hyeon-Ji;Yim, Yong-Hyeon;Kim, Jeongkwon;Hwang, Euijin
    • Mass Spectrometry Letters
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    • v.5 no.2
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    • pp.57-61
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    • 2014
  • A gravimetric standard addition method combined with internal standard calibration has been successfully developed for the accurate analysis of total arsenic in a laver candidate reference material. A model equation for the gravimetric standard addition approach using an internal standard was derived to determine arsenic content in samples. Handlings of samples, As standard and internal standard were carried out gravimetrically to avoid larger uncertainty and variability involved in the volumetric preparation. Germanium was selected as the internal standard because of its close mass to the arsenic to minimize mass-dependent bias in mass spectrometer. The ion signal ratios of $^{75}As^+$ to $^{72}Ge^+$ (or $^{73}Ge^+$) were measured in high resolution mode ($R{\geq}10,000$) to separate potential isobaric interferences by high resolution ICP/MS. For method validation, the developed method was applied to the analysis of arsenic content in the NMIJ 7402-a codfish certified reference material (CRM) and the result was $37.07mg{\cdot}kg^{-1}{\pm}0.45mg{\cdot}kg^{-1}$ which is in good agreement with the certified value, $36.7mg{\cdot}kg^{-1}{\pm}1.8mg{\cdot}kg^{-1}$. Finally, the certified value of the total arsenic in the candidate laver CRM was determined to be $47.15mg{\cdot}kg^{-1}{\pm}1.32mg{\cdot}kg^{-1}$ (k = 2.8 for 95% confidence level) which is an excellent result for arsenic measurement with only 2.8 % of relative expanded uncertainty.

Calibration and Uncertainty Analysis of Sample-Time Error on High Jitter of Samplers

  • Cho, Chihyun;Lee, Joo-Gwang;Kang, Tae-Weon;Kang, No-Weon
    • Journal of electromagnetic engineering and science
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    • v.18 no.3
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    • pp.169-174
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    • 2018
  • In this paper, we propose an estimation method using multiple in-phase and quadrature (IQ) signals of different frequencies to evaluate the sample-time errors in the sampling oscilloscope. The estimator is implemented by ODRPACK, and a novel iteration scheme is applied to achieve fast convergence without any prior information. Monte-Carlo simulation is conducted to confirm the proposed method. It clearly shows that the multiple IQ approach achieves more accurate results compared to the conventional method. Finally, the criteria for the frequency selection and the signal capture time are investigated.

Nitrogen Depth Profiles in Ultrathin Oxynitride Films

  • Shon, H.K.;Kang, H.J.;Chang, H.S.;Kim, H.K.;Moon, D.W.
    • Journal of Korean Vacuum Science & Technology
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    • v.6 no.1
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    • pp.5-7
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    • 2002
  • For quantitative N depth profiling, N profiles were measured in a~3 m Si oxynitride by low energy O$\sub$2+/sputtering and the result was calibrated with MEIS analysis of the N thickness and areal density. The quantitative depth profile of nitrogen showed the pileup of nitrogen atoms at the interface of ultrathin oxynitride films.

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KS Standard for Logistics Facilities and Equipments (물류시설 및 기기의 KS 표준규격)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2007.04a
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    • pp.449-456
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    • 2007
  • This paper presents system of physical distribution module, and classification of logistics equipments. This study also introduces equipment standards of logistics facilities, and environmental rules for distribution center. Moreover, this paper shows safety standard and marking for logistics equipments and tools.

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A Study on General-Standard Conformance Test Framework and Methodology of Defense Information Technical Standard (국방정보기술표준 일반 표준적합성시험 프레임워크 및 방법론 연구)

  • Seo, Minwoo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.6
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    • pp.744-751
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    • 2016
  • Interoperability tests are required to determine whether network-based defense systems successfully share and exchange certain services, information, and data. We must examine various aspects of interoperability. The DITA (Defense Information Technical stAndard) is the basis for interoperability. However, DITA is being applied to the defense system in a state that the standard test methods and procedures are not established. And there is no test method and procedure of the DITA well applicable to military weapons systems or information systems. Therefore, in this paper, we propose a framework that includes procedures, methodologies, so as to test whether a standard is applied to the DITA in terms of Standard Conformance Test.

Variable Sampling Interval $\bar{X}$ Control Chart Using Weighted Standard Deviation Method (가중표준편차를 이용한 가변표본채취간격 $\bar{X}$ 관리도)

  • Chang, Youngsoon
    • Journal of the Korean Operations Research and Management Science Society
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    • v.39 no.1
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    • pp.1-12
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    • 2014
  • This article proposes a variable sampling interval (VSI) $\bar{X}$ control chart using weighted standard deviation (WSD) method for skewed populations. The WSD method decomposes the standard deviation of a quality characteristic into upper and lower deviations and adjusts control limits and warning limits of a control chart in accordance with the direction and degree of skewness. A control chart constant is derived for estimating the standard deviation of skewed distributions with the mean of sample standard deviations. The proposed chart is compared with the conventional VSI $\bar{X}$ control chart under some skewed distributions. Simulation study shows that the proposed WSD VSI chart can control the in-control average time to signal (ATS) as an adequate level better than the conventional VSI chart, and the proposed chart can detect a decrease in the process mean of a quality characteristic following a positively skewed distribution more quickly than the standard VSI chart.

Trend Analysis and Revision of the University Library Standard in Korea (대학도서관기준의 동향분석과 개정안 연구)

  • Yoon, Hee-Yoon
    • Journal of Korean Library and Information Science Society
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    • v.42 no.2
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    • pp.5-28
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    • 2011
  • The ultimate mission of the university library is to provide the various information services in support of the teaching, research, and public service missions of the university. The achievement of the mission requires the optimal development and timely revision of university library standard that can be used as an operating guidelines and assessment tools. On the basis of this justification, this study has compared the trend and feature of library standards in major countries(USA, Canada, UK, Japan, Taiwan), analysed the problems and limitations of legal and recommended standards in Korea, and suggested the revised plan of Korean university library standard focusing on collections, staffs, and facilities.

A Study on Utilization of De Facto Standards for National Standards (사실상표준의 국가표준으로의 활용 방안에 관한 연구)

  • Choi, Jae-Jin;Chung, Soon-Suk;Kim, Kwang-Soo
    • Proceedings of the Safety Management and Science Conference
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    • 2009.11a
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    • pp.309-326
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    • 2009
  • De facto standards can be divided into the U.S. group standards' and 'forum and the consortium standard. mainly applies to high-tech industry forums, and a consortium standard of the industry given the nature of the standard are frequently revised, the country Due to the introduction of standard time. Economic loss to consider when in reality, the introduction of national standards of the United States is limited to the desirable standard, and the fact the actual award of standards, national standards, or if you want to introduce standard, each of depending on the type of attitude and strategy for standards by category, based on the characteristics of each body strategy and are needed. Through this study on utilization of de facto standards for national standards, it is researched that major de facto standards bodies status and domestic industrial fields which need utilization of de facto standards for national standards. Through overseas Case, effective usage of de facto standards will be obtained.

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