• 한국안전학회지
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• 제32권5호
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• pp.54-61
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• 2017

The purpose of this study is to develop standard reference materials for safety control of construction materials considering the required performance of standard materials including flow performance incorporating particles. The flow characteristics of concrete are very complicated depending on mixing proportions of constituent materials, admixtures, amount of mixing, type of mixer, time of mixing, temperature and so forth. Uncertainties and multidimensional properties of concrete have been evaluated through various studies but there are few researches for the development of standard reference material. In this study, based on the rheological concept, the flow performance of construction materials was evaluated to understand the properties of standard reference materials and was finally obtained representing materials which simulate the standard reference materials.

• 한국안전학회지
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• 제34권5호
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• pp.111-118
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• 2019

Recently, a variety of special concrete structures have been designed in domestic and overseas construction markets and more advanced construction technology is required. Therefore, it is necessary to secure quantitative construction technology. For this purpose, it is essential to develop a standard reference material having a constant flow performance and quality to evaluate quantitative performance. On the other hand, the flowability of the concrete is greatly influenced by the flowability of the cement paste. Also, in consideration of design strength and workability, mix design is carried out at various mixing ratios according to the purpose of the site. Therefore, in this study, based on the derived components of standard reference materials for cement paste, we suggested mixing ratio of standard reference materials that can uniformly simulate the flow characteristics of cement paste according to W/C. As a result, it was found that the yield stress was determined by the ratio of water and glycerol but plastic viscosity was controled by limestone content. Finally, the ratio of standard reference materials to simulate the rheological range of cement paste by W/C was suggested.

• 약학회지
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• 제45권2호
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• pp.227-236
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• 2001

The complexity and variability of both the biologicals and the bioassays used to test them led to the use of the reference standard- a sample of the product of defined purity and potency, against which all preparations of that product must be calibrated. In order to prepare and establish KFDA reference standard for recombinant human growth hormone (somatropin), somatropin substance was filled in ampoules in National Institute for Biological Standards and Control (NIBSC). The candidate KFDA reference standard for somatropin (designated as 98/674) was evaluated to determine the suitability of serving as a KFDA reference standard for somatropin by the collaborative study, in which 10 laboratories participated. Physicochemical analysis and in vivo bioassay were performed by direct comparison with the international somatropin standard 88/624. 98/674 was identified as somatropin by SDS-PAGE, IEF, peptide mapping, and HPLC. Determination of somatropin content by SE-HPLC yielded a mean estimate of 2.01 mg somatropin per ampoule. Data from the study also yielded mean values of 0.39 $\pm$ 0.26% for high molecular weight impurities by SE-HPLC and mean values of 2.13 $\pm$ 1.29% for somatropin related proteins by RP-HPLC. Estimates of relative potency by weight gain bioassay in the hypophysectomised rats showed that relative potency of KS 98/674 was 1.07 aganist IS 88/624. Based on the results of the collaborative study, the candidate reference standard for somatropin is suitable to serve as a KFDA reference standard for somatropin.

• 한국문헌정보학회지
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• 제37권4호
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• pp.131-149
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• 2003

신뢰도가 공인된 과학기술데이터는 같은 분야 연구자들이 지속적이면서 반복적으로 사용할 수 있도록 물리화학적 상수, 공인된 물성값, 또는 공인된 과학기술적 통계 값을 가지고 있어야 한다. 이러한 측정데이터는 정보의 정확도와 신뢰도를 과학적으로 분석, 평가하여 공인함으로써 국가적으로 모든 분야에 널리 사용할 수 있는 참조표준데이터(Standard Reference Data)로 관리되어야 한다. 본 논문에서는 연구중에 생산된 다양한 실험데이터를 국가 참조표준 데이터로서 관리되어야 하는 필요성과 국가참조표준 센터 설립을 위한 방안을 제시해 본다. 그 시도로 측정표준 연구정보를 하나의 참조정보로 이용할 수 있도록 측정표준 연구정보 시스템을 개발하였고 이 시스템에 대한 운영체계를 자세히 소개함으로서 국내 참조정보 관리에 대한 방안을 제시하고자 한다.

• 한국항행학회논문지
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• 제20권6호
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• pp.580-587
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• 2016

본 논문에서는 항공기조종사 자격증명 취득을 위한 표준교재 제공의 필요성과 제공 방법에 관한 제안을 목적으로 미국 FAA와 한국 공군 사례 분석과 항공기조종사 자격증명을 취득한 조종사 및 예비조종사 178명의 자료를 실증 분석하였다. 사례분석 결과 국내의 경우 표준교재 제공에 제한을 두고 있는 실정과는 달리 미 FAA와 한국공군의 경우 표준교재를 제공하고 있는 것으로 나타났다. 또한 실증분석결과 항공조종사 자격증명 취득을 위해 표준교재 제공의 필요성을 인식하고 있었으며, 그 중요도 또한 매우 높은 것으로 나타났다. 이와 같은 결과는 역량 있는 항공기조종사 육성을 위해서는 표준교재의 제공이 필요하며, 이는 항공운송산업의 급속한 성장에 의한 항공기조종사 부족상황을 완화시키고, 다양한 항공기 관련 사고를 예방하는데 있어 매우 중요하다는 것을 보여주는 결과이다.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.299-303
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• 2016

Prompt gamma activation analysis using a thermal neutron-guided beam at Japan Atomic Energy Agency JRR-3M was applied for the precise determination of Si in silicon nitride ceramic reference materials [Japan Ceramic Reference Material (JCRM) R 003]. In this study, the standard addition method coupled with internal standard was used for the nondestructive determination of Si in the sample. Cadmium was used as internal standard to obtain the linear calibration curves and to compensate for the neutron beam variability. The analytical result of determining Si in JCRM R 003 silicon nitride fine powder ceramic reference materials using prompt gamma activation analysis was in good agreement with that obtained by classical gravimetric analysis. The relative expanded measurement uncertainty (k = 2) associated with the determined value was 2.4%.

• 품질경영학회지
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• 제47권2호
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• pp.315-325
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• 2019

Purpose: The purpose of this study was to propose useful standards evaluation method using standards networks by analyzing the relationship between normative references citation information list. Methods: The collected data through the survey were analyzed using social network analysis. The measurement tools used for this study were divided into three dimensions such as certificate standard, normative reference and degree centrality. Results: The results of this study are as follows; regarding the influence of standard information, It is meaningful that the research using normative reference item among the bibliography information that the standard itself possesses. The analysis of social network analysis data of population standard, normative reference and the correlation analysis with sales, a variable representing actual utilization performance, suggested the importance of the standard and how to evaluate it. Conclusion: In prioritizing standard maintenance, more efficient management will be possible if centrality figures of standard network information are analyzed and used for standard maintenance.

• 대한지역사회영양학회지
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• 제3권4호
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• pp.533-541
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• 1998

This study compares the growth performance(weight-for-age Z-score, height-for-age Z-score, weight-for-height Z-score) of one- to three- month-old Korean infants(n=232) with the Korean standard(1994) and NCHS reference(1983). The weight-for-age Z-scores(WAZ) by the Korean standard were -2∼1,5 for males and -3∼1 for females. The NCHS reference, WAZ results were -1∼2.5 and -2.5∼3.5 for males and females, respectively. The WAZ compared Korean standard showed no subjects with overnutrition. But 1.3% of the infants showed signs of malnutrition. Comparison with NCHS reference revealed that 0.4% of the infants were malnourished and 7.0% of the infants were overnourished. The WAZ of formula-fed infants were distributed higher than breast-fed infants, but that was not significant. The height-for-age Z-score(HAZ) by the Korean standard were -4.5%∼1.5% for males and -4∼1.5% for females. According to the NCHS reference, HAZ were -2.5%∼2.5% and -3∼3 for males and females, respectively. When the WAZ was compared with the Korean standard, there was no overnutrition but 16% of the infants showed signs of malnutrition. The NCHS reference, revealed that 6.9% of the infants were malnourished and 1.8% of the infants were ovemourished. The weight-for-height Z-scores(WHZ) by the Korean standard were -2∼5 for males and -2.5∼5 for females. The NCHS reference WAZ scores were -1∼4 and -1.5∼4.5 for males and females, respectively. When the WHZ was compared with the Korean standard, 2.2% of infants were malnourished and 19.5% were overnourished. There were no malnourished subjects according to the NCHS reference and 19.1% of the infants were overnourished. When the three Z-scores are considered together, 92.0% of the infants should a normal growth status, there was no malnutrition, and 8.0% of the infants were overnourished. The growth performance was evaluated differently according to the type of standards. Thus, it is necessary to set proper growth standards for infants, according to which classification of feeding methods is chosen. A longterm and careful assessment of infants's growth performances to develop any group of standards.

• Korean Journal of Radiology
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• 제24권2호
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• pp.155-165
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• 2023

Objective: Little is known about the effects of using different expert-determined reference standards when evaluating the performance of deep learning-based automatic detection (DLAD) models and their added value to radiologists. We assessed the concordance of expert-determined standards with a clinical gold standard (herein, pathological confirmation) and the effects of different expert-determined reference standards on the estimates of radiologists' diagnostic performance to detect malignant pulmonary nodules on chest radiographs with and without the assistance of a DLAD model. Materials and Methods: This study included chest radiographs from 50 patients with pathologically proven lung cancer and 50 controls. Five expert-determined standards were constructed using the interpretations of 10 experts: individual judgment by the most experienced expert, majority vote, consensus judgments of two and three experts, and a latent class analysis (LCA) model. In separate reader tests, additional 10 radiologists independently interpreted the radiographs and then assisted with the DLAD model. Their diagnostic performance was estimated using the clinical gold standard and various expert-determined standards as the reference standard, and the results were compared using the t test with Bonferroni correction. Results: The LCA model (sensitivity, 72.6%; specificity, 100%) was most similar to the clinical gold standard. When expert-determined standards were used, the sensitivities of radiologists and DLAD model alone were overestimated, and their specificities were underestimated (all p-values < 0.05). DLAD assistance diminished the overestimation of sensitivity but exaggerated the underestimation of specificity (all p-values < 0.001). The DLAD model improved sensitivity and specificity to a greater extent when using the clinical gold standard than when using the expert-determined standards (all p-values < 0.001), except for sensitivity with the LCA model (p = 0.094). Conclusion: The LCA model was most similar to the clinical gold standard for malignant pulmonary nodule detection on chest radiographs. Expert-determined standards caused bias in measuring the diagnostic performance of the artificial intelligence model.

• 한국도서관정보학회지
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• 제39권2호
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• pp.147-167
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• 2008

본 연구는 중국 대학도서관의 가상참고서가 구축 현황을 조사, 분석함으로써 문제점을 발견하고, 가상참고서 가가 향후 지향해야 할 방향을 제시하는데 목적을 두고 있다. 본 연구에서는 이를 위해 가상참고서가의 이론적 토대를 마련하였다. 그리고 이 이론에 근거하여 가상참고서가의 평가기준을 세우고 이 기준에 따라 중국 "985프로젝트"에 입선된 38개 대학도서관을 중심으로 가상참고서가의 구축현황을 분석함으로써 협동구축의 당위성을 이끌어냈다.