• 제목/요약/키워드: Primary standard

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손실계수 표준기 제작 및 그 특성 (Development and Its Characteristics of a Dissipation Factor Standard)

  • 김한준;강전홍;한상옥
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.527-528
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    • 2006
  • A dissipation factor standard of decade type having the range of 1 to 0.0001 at the frequency of 1 kHz and 10 kHz was fabricated using "T" networks combined R and C components. The values of the fabricated dissipation factor standard were adjusted within 1% of the nominal values at 0.0001 dial range and 0.05% at the others. This dissipation factor standard is used as a working standard for calibration of a impedance measurement meter at KRISS and as a primary standard of dissipation factor field at NML-SIRIM in Malaysia.

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초등학교 급식의 영양관리 현황 및 개선 방안 연구 (Strategies to Improve Nutritional Management in Primary School Lunch Program)

  • 임경숙;이태영;김초일;최경숙;이정희;권순주;김미옥
    • 대한영양사협회학술지
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    • 제10권2호
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    • pp.235-245
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    • 2004
  • The Korea School Lunch Program mandates that school meals should safeguard the health and well-being of our children. School meals provide a nutritious diet that contains at least ⅓ of the daily Recommended Dietary Allowances of necessary nutrients at reasonable prices. This study was performed to assess the nutritional management of primary school meals, and to provide basic data for improvement of school meal nutritional guidelines. Three hundred and thirty six dietitians who worked at primary schools were recruited using a stratified sampling method. A survey was done by e-mail with a set of questionnaires about nutritional meal management. During school lunch planning, dietitians referred nutrition standards with priority, followed by students' food preferences and food hygiene. They considered energy as a most important nutrient during primary school lunch planning, followed by protein and calcium. Protein is usually over-served, whereas iron, vitamin A and calcium are usually under-served during primary school meal planning. For first and second grade primary students, grains, meat and vegetable side dishes seemed to be large compared to their eating capacity. Over 92% of school dietitians agreed the needs of food group standards for primary school lunch program. For making a checklist of the school lunch program, energy, protein and calcium were highly recommended, and meat.fish.egg group, vegetable.fruit group and dairy group were also highly recommended by school dietitians. Cooking method was also highly recommended. School dietitians proposed that remodeling of school kitchens and new cooking machine were the most important factors for improving school lunch system. These results suggest that food standards should be established for health-oriented nutritional management of primary school lunch programs. Nutritional checklists could include nutrient-rich foods and food groups, and items about cooking methods.

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제7차 개정 교육과정에 대응한 초.중.고등학교의 시설기준에 관한 연구 - 단위 학습공간 및 특별교실을 중심으로 - (A Study on the Facility Criterion for the Revised 7th Curriculum of Elementary Schools and Secondary Schools - Focused on the Unit Learning Space and Special Classroom -)

  • 최병관;박흥균
    • 교육시설
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    • 제16권2호
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    • pp.67-77
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    • 2009
  • This study was made in order to provide the groundwork for the revised 7th education curriculum of primary and secondary education's facility criterion. Throughout this study, in which we may accomodate the new education curriculum, we prepare the guide for the standard criterion of the school systems in order to reflect the flexibility of various dictinctive regional education conditions and school qualities considering the purpose of new standard criterion of school facilities. Below is the summary of the study. Regular classroom's standard size, which is the basic module for the scale of the educational institution, accomodates current standards. Number of students per class is aimed to fit the standard number of the level of OECD member countries' in order to prepare for the future ; that is, 30 students in primary, secondary and high school to be the standard number of student per class, depending on the district conditions and construction point of time. It is advised that the number of extracurricular classrooms, according to the standard criterion of subject and hour allotment, to reflect the regional and institution's distinctive qualities by indicating the number of hours and classrooms including decimal points. That is to be done so that the founder and the interested parties of the institution, along with the architect can put to practical use when planning and designing the institution.

pH 측정 시스템의 표준화에 관한 연구 (Studies on the Standardization of pH Measurement System)

  • 이화심;김명수;김진복;오상협
    • 대한화학회지
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    • 제42권4호
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    • pp.432-442
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    • 1998
  • $pH=-loga_H$ 정의에서 pH는 단일 이온의 활동도항을 포함하므로 단지 측정의 방법만으로는 결정되어질 수 없고 근사법을 필요로 한다. 근사법에 의한 pH 측정은 수소전극과 은/염화은 전극을 사용한 액간 접촉이 없는 cell의 기전력 측정으로부터 이루어지는 방법이며, 이 과정을 통해 pH 값이 인증된 pH의 일차 표준 물질을 얻을 수 있다. 일반적인 pH 미터와 전극을 검정하는 데에는 인증된 pH 값을 가지는 표준 완충용액을 사용하므로 표준 완충용액의 pH 값 정혹도는 실제 측정된 pH 값의 실효성을 제한할 수 있다. 본 연구에서는 정확한 pH의 측정을 위해서 pH 값을 인증할 수 있는 시스템을 구축하기 위한 제반의 연구를 수행하였으며, 이를 토대로 pH 1.6∼12.5의 범위에 해당하는 완충용액의 pH를 0.005 pH 단위 이내의 불확도로 인증하였다.

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Octylmethoxycinnamate의 SPF 지수와 피부자극지수와의 상관성 연구 (Studies on the Correlation between SPF index and Primary Irritation Index of Octylmethoxycinnamte)

  • 서수경;김종원;최주영;서경원;박창원;김규봉;김광진;이선희
    • 한국환경성돌연변이발암원학회지
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    • 제22권4호
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    • pp.296-302
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    • 2002
  • In recent years, the safety of sunscreens have been challenged based on the reports of its adverse effects on users; dermatitis, allergic contact dermatitis, photoallergic contact dermatitis. In the toxicological aspect, the need to investigate the safety of sunscreens is steadily increasing. However, there were few studies on the correlation between sun protection factor (SPF) and the safety of sunscreens. The objective of this study was to assess whether there was a correlation between SPF and the skin irritation index of sunscreens. Octyl methoxycinnamate (OMC) was selected, which was the most frequently used (about 92% in korea and about 90% in the world) in sunscreens. In vitro SPF test was performed using the standard samples recommended by KFDA guideline. We examined primary and cumulative skin irritation and eye irritation of OMC standard sample as well as homosalate. As in vitro SPF was increased, skin irritation index was increased in primary skin irritation test ($r^2$=0.986) and cumulative skin irritation test ($r^2$=0.939). In addition, OMC was non-irritating and non-sensitizing. In this results, there was a good correlation between SPF index and skin irritation index.

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Secondary Circulating Tumor Cells (CTCs) but not Primary CTCs are Associated with the Clinico-Pathological Parameters in Chilean Patients With Colo-Rectal Cancer

  • Murray, Nigel P;Albarran, Vidal;Perez, Guillermo;Villalon, Ricardo;Ruiz, Amparo
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권11호
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    • pp.4745-4749
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    • 2015
  • Background: The aim of this study was to assess detection of circulating tumor cells (CTC) using anti-CEA pre and post surgery in Chilean patients with colo-rectal cancer. Materials and Methods: The presence of CTCs was evaluated in 80 colorectal cancer patients pre and post surgery using standard immunocytochemistry and the results were compared with findings for standard clinico-pathological parameters. Results: In patients presurgery CEA (+) CTCs were frequently found, with no relation to tumor size or nodal status. After surgery, the presence of CTCs was associated with such clinico-pathological parameters. The frequency of CTC detection in node positive patients did not change after surgery. In patients with metastasis there was also no change in the frequency of CTC detection, and clusters of 3 or more CTCs were evident. Conclusions: Secondary CTCs are associated with clinico-pathological parameters only after surgical removal of the primary tumor, and might be important in identifying patients at high risk of relapse. Primary CTCs detected before surgical removal are frequently found, are not associated with the clinico-pathological parameters and might have a role in cancer screening. These findings suggest the need for studies with a larger population of patients.

HALO : 효율적 표준셀 배치 알고리듬 (HALO : An Efficient Global Placement Strategy for Standard Cells)

  • 양영일;경종민
    • 대한전자공학회논문지
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    • 제26권10호
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    • pp.1598-1605
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    • 1989
  • This paper describes an efficient global cell (module) placement strategy called HALO (Hierarchical Alternating Linear Ordering)which generates global 2-D placement of circuit modules by hierarchical application of linear ordering in alternating direction. We tried, in principle, to explain why HALO should perform better than other typical, somehat successful, analytical approaches such as min-cut, force-directed relaxation(FDR)or its likes. We have implemented HALO as a program for standard cell placement. Experimental results on two benchmark circuits, primary and primary 2 consisting of 752 and 2907 cells, respectively have shown a decrease of half-perimeter routing length by 7% and 24%, respectively compared to the best available results obtained so far. Total CPU time including the following detailed placement was less than half of the earlier work.

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Experimental Measurement and Monte Carlo Simulation the Correction Factor for the Medium-Energy X-ray Free-air Ionization Chamber

  • Yu, Jili;Wu, Jinjie;Liao, Zhenyu;Zhou, Zhenjie
    • Journal of the Korean Physical Society
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    • 제73권10호
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    • pp.1466-1472
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    • 2018
  • A key comparison has been made between the air-kerma standards of the National Institute of Metrology (NIM), China, and other Asia Pacific Metrology Programme (APMP) members in the medium-energy X-ray. This paper reviews the primary standard Free-air ionization chamber correction factor experimental method and Monte Carlo simulation method in the NIM. The experimental method and the Monte Carlo simulation method are adopted to obtain the correction factor for the medium-energy X-ray primary standard free-air ionization chamber at 100 kV, 135 kV, 180 kV, 250 kV four CCRI reference qualities. The correction factor has already been submitted to the APMP as key comparison data and the results are in good agreement with those obtained in previous studies. This study shows that the experimental method and the EGSnrc simulation method are usually used in the measurement of the correction factor. In particular, the application of the simulation methods is more common.

Evaluating Higher Diploma in English Language Teaching for the Primary Stage from the Teachers' Perspectives

  • Hashem A. Alsamadani
    • International Journal of Computer Science & Network Security
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    • 제23권9호
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    • pp.91-94
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    • 2023
  • This study aims to evaluate the Higher Diploma in English for the Primary Stage from the diploma students' perspectives. A questionnaire was designed consisting of 25 items distributed in two areas: cognitive/academic preparation and professional/skill preparation. The following statistical analyses were used: means, standard deviations, t-test, and one-way analysis of variance (ANOVA). The study results showed that the level of evaluation of the two domains in the program was low. The study also showed no statistically significant differences between the means of educational diploma students when evaluating the Higher Diploma in English for the Primary Stage due to their academic specialization (Arabic language, social sciences, and Islamic studies). In conclusion, the researcher suggested a developmental mechanism derived from the study results to improve the higher Diploma in English for the Primary Stage.

ST세그먼트 검출성능향상을 종속 적응필터의 세계 (Design of a Cascade Adaptive Filter for the Performance sn Detection of Segment)

  • 박광리;이경중
    • 대한의용생체공학회:의공학회지
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    • 제16권4호
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    • pp.517-524
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    • 1995
  • This paper is a study on the design of the cascade adaptive filter (CAF) for baseline wandering elimination in order to enhance the performance of the detection of ST segments in ECG. The CAF using Least Mean Square (LMS) algorithm consists of two filters. The primary adaptive filter which has the cutoff frequency of 0.3Hz eliminates the baseline wandering in raw ECG The secondary adaptive filter removes the remnant baseline wandering which is not eliminated by the primary adaptive filter. The performance of the CAF was compared with the standard filter, the recursive filter, and the adaptive impulse correlated filter (AICF). As a result, the CAF showed a lower signal distortion than the standard filter and the AICF. Also, the CAF showed a better perf'ormance in noise elimination than the standard filter and the recursive filter. In conclusion, considering the characteristics of the noise elimination and the signal distortion, the CAF shows a better performance in the removal of the baseline wandering than the other three Otters and suggests the high performance in the detection of ST segment.

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