• Title/Summary/Keyword: Material Standards

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Development and Characteristics of DC/AC Resistance Standard (직류/교류 저항표준기 제작 및 그 특성)

  • Kim, Han-Jun;Kang, Jeon-Hong;Yu, Kwang-Min;Han, Sang-Ok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.519-520
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    • 2008
  • 교류에서의 전기저항값은 저항 elements 사이에서 나타나는 stray 전기용량과 elements의 길이에서 유도되는 인덕턴스의 영향으로 직류에서의 저항값과 차이를 보이게 된다. 이러한 직류와 교류에서의 저항값 차이가 대단히 작게 나면서 직류에서와 측정하는 교류에서의 저항값의 차이를 계산에 의해서 산출할 수 교류저항 표준기가 개발되었다. 개발된 교류저항표준기는 bi-filar 구조의 1 $k\Omega$로서, 1.6 kHz에서 직류/교류 저항값의 차이는 0.02 ${\mu}{\Omega}/{\Omega}$ 보다 작으며, 시정수는 1 kHz에서 $(8{\pm}2)\times10^{-10}$으로 측정되었다. 개발된 교류저항 표준기는 교류저항 국가표준에 최상급 표준기로 사용이 되어질 것이다.

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Development of a Mushroom Powder Certified Reference Material for Element Analysis

  • Betru, Tegegn Gizachew;Yim, Yong-Hyeon;Lee, Kyoung-Seok
    • Mass Spectrometry Letters
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    • v.11 no.4
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    • pp.108-112
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    • 2020
  • A certified reference material (CRM) for the analysis of nutrient elements in an edible mushroom (Ganoderma lyceum) powder has been developed (KRISS CRM 108-10-011). The mass fractions of calcium (Ca), iron (Fe), and zinc (Zn) were measured by isotope dilution inductively coupled plasma mass spectrometry (ID ICP/MS). To dissolve the fungi cell wall of mushroom consisted of chitin fibers, sample preparation method by single reaction chamber type microwave-assisted acid digestion with acid mixtures was optimized. The mean measurement results obtained from 12 sample bottles were used to assign as the certified values for the CRM and the between-bottle homogeneities were evaluated from the relative standard deviations. The certified values were metrologically traceable to the definition of the kilogram in the International System of Units (SI). This CRM is expected to be used for validation of analytical methods or quality control of measurement results in analytical laboratories when they determine the mass fractions of elements in mushroom or other similar samples.

A Study on the Architectural facility standards of integrated child care facility (통합보육시설의 시설 및 설비 기준에 관한 연구)

  • Kim Young-Eun;Park Hyeon-Soo;Lee Keon-Ha
    • Korean Institute of Interior Design Journal
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    • v.15 no.3 s.56
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    • pp.136-143
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    • 2006
  • This research proposes the importance of physical environment if integrated early childhood education. For a successful integration of children's education, we processed fundamental research on requirements of facility and equipments, looking at related standards and code on handicapped person's convenience facility. Also, this research alms at providing first step to establish evaluation method and quality assurance standards of integrated child care facility, regarding space planning of handicapped children. By examining home and abroad material and analyzing handicapped children's convenience facility standards, this research pursues improving the basis of planning criteria. As present criteria of relevant regulations appears not to handle detailed facility standards, and the handicapped people's facility is for childhood education, it is necessary first to differentiate indispensable equipments from optional one, then categorize them into more specific needs.

Ceramic - Polymer Nanocomposite: Alternate Choice of Bone

  • Sarkar, Debasish;Chu, Min-Cheol;Cho, Seong-Jai
    • Journal of the Korean Ceramic Society
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    • v.45 no.6
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    • pp.309-319
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    • 2008
  • This study evaluates a range of materials that may be used to design prostheses for bone. It is found that nanocrystalline ceramic-polymer composite could be the best material for prosthetic bone with respect to biocompatibility, morphology, chemistry, and compatibility with the piezoelectric and mechanical behavior of long human bones, such as the femur.

Development of Dementia Care Standards (치매 간호 표준 개발)

  • Ha, Ju-Young
    • Journal of Korean Academy of Nursing
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    • v.40 no.5
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    • pp.631-641
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    • 2010
  • Purpose: This study was done to develop standards for dementia care as a baseline for professional nurses to provide a framework for dementia care evaluation Methods: The dementia care standards were developed through a literature review and focus group discussions. According to the Delphi method, the data analysis was conducted using the Content Validity Index (CVI). Results: The final set of 18 standards on dementia care was developed through one round of CVI. The standards included four structural standards: 'Organization of nursing system', 'Operating system', 'Management of human resources', 'Management of material resources', 13 procedural standards: 'Advanced assessment', 'Nursing diagnosis', 'Nursing plam', 'Advanced nursing implementation', 'Evaluation', 'Education', 'Research', 'Consultation', 'Counseling and cooperation', 'Development of specialty', 'Utilizing resources', 'Nursing quality assurance', 'Ethics', and one standard concerning outcome ('Evaluation of nursing tasks in care of patients with dementia'). The final set of 55 criteria on care of patients with dementia was confirmed through two rounds of CVI. The final 171 indicators were confirmed through four rounds of CVI. Conclusion: These dementia care standards provides a framework that allows registered nurses to clarify their roles and tasks in the care of patients with dementia and provides evaluation criteria.

Employing Al Etch Stop Layer for Nb-based SNS Josephson Junction Fabrication Process (Al 식각정지층을 이용한 Nb-based SNS 조셉슨 접합의 제조공정)

  • Choi, J.S.;Park, J.H.;Song, W.;Chong, Y.
    • Progress in Superconductivity
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    • v.12 no.2
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    • pp.114-117
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    • 2011
  • We report our efforts on the development of Nb-based non-hysteretic Josephson junction fabrication process for quantu device applications. By adopting and modifying the existing Nb-aluminum oxide tunnel junction process, we develop a process for non-hysteretic Josephson junction circuits using metal-silicide as metallic barrier material. We use sputter deposition of Nb and $MoSi_2$, PECVD deposition of silicon oxide as insulator material, and ICP-RIE for metal and oxide etch. The advantage of the metal-silicide barrier in the Nb junction process is that it can be etched in $SF_6$ RIE together with Nb electrode. In order to define a junction area precisely and uniformly, end-point detection for the RIE process is critical. In this paper, we employed thin Al layer for the etch stop, and optimized the etch condition. We have successfully demonstrated that the etch stop properties of the inserted Al layer give a uniform etch profile and a precise thickness control of the base electrode in Nb trilayer junctions.

Field Applicability Of Emergency Road Repair Material Using the CAC (CAC를 이용한 긴급도로 보수재의 현장 적용성)

  • Hyun, Ji-Soo;Kim, Jin-Man;Choi, Hong-Beom;Lee, Ha-Na;Koo, Ja-Sul
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.05a
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    • pp.154-155
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    • 2015
  • This study was to review the basic characteristics in order to evaluate field application of the emergency road repair materials for development of CAC(Calcium Aluminate Composite) usage. The experiment was conducted with two phases of field and laboratory conditions and the laboratory experiment consisted indoor and outdoor tests for compressive and flexural strength. In the result of an experiment, for the compressive strength test, the specimens that cured in the laboratory conditions were not satisfied the requirement of standards, while the specimens that cured in the field conditions were well satisfied with those. For flexural strength test, the result value was satisfied with the requirement on the standards only in outdoor curing condition of laboratory experiment. Based on these results, it is expected that the CAC can be used as an emergency road repair material for field conditions.

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A Study on Electronic Component Failure Rate Trend Based on Technology Changes (전자기술의 발전과 전자부품 기본 고장률의 추이)

  • Jang, Ju-Su;Yun, Cha-Jung;Lee, Eun-Kyu;Lee, Eul-Jae;Jang, Jeong-Hoon;Kim, Yong
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.2527-2538
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    • 2011
  • The Reliability started for MILitary purposes during World War II in 1942, getting more important for maintenance, safety, etc in modern society. As technologies develop, also international standards for measuring the reliability is advancing. RAMS activities for maintenance, safety verification is material to national railroad. And for this, it needs quick response for the changes of standards. Even now standards are upgrading for developing electronic technologies. Therefore analysis of failure rate's trend about such standards is judged necessary. So We submit a this paper for comparative analysis of changing process standards according to development of electronic technologies and reliability. At first, we compared actual usage ratio of standards for understanding the current state of usage. Based of these state of usage, discuss the major standard. And then, introduced reliability standards's trend, calculation method of failure rate and difference of failure rate calculation standard according to march of time. In this paper, used standards are MIL-HDBK-217F, Telcodia, etc.

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