• 한국결정성장학회지
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• 제7권1호
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• pp.151-162
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• 1997

Pivalic acid를 진공 증류 및 zone refining을 이용 고순도로 정제하여 온도 표준 기준 물질로의 개발 가능성을 시험하였다. melting plateau curve를 이용하여 99.9997% 순도의 pivalic acid cell들의 삼중점을 측정한 결과 $35.956\pm 0.003^{\circ}C$를 얻을 수 있었다. 이상의 정밀도를 갖는 pivalic acid 삼중점 cell들은 고정밀도를 요구하지 않는 일반 thermistor 온도계류의 보정용으로 충분히 사용 가능한 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1541-1544
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• 2002

The concentration of B in steels is important due to its influence on mechanical properties of steel such as hardenability, hot workability, and creep resistance. An analytical method has been developed to determine B in steel samples by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). National Institute of Standard and Technology Standard Reference Material (NIST SRM) 348a was analyzed to validate the analytical method. The steel sample was digested in a centrifuge bottle with addition of aqua regia and $^{10}B$ spike isotope. Sample pH was then adjusted to higher than 10 to precipitate most matrix elements such as Fe, Cr, and Ni. After centrifugation, the supernatant solution was passed through a cation exchange column to enhance the matrix separation efficiency. B recovery efficiency was about 37%, while matrix removal efficiency was higher than 99.9% for major matrix elements. The isotope dilution method was used for quantification and the determined B concentration was in good agreement with the certified value.

• Smart Structures and Systems
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• 제18권1호
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• pp.1-16
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• 2016

Model Order Reduction (MOR) denotes the theory by which one tries to catch a model of order lower than that of the real model. This is conveniently pursued in view of the design of an efficient structural control scheme, just passive within this paper. When the nonlinear response of the reference structural system affects the nature of the reduced model, making it dependent on the visited subset of the input-output space, standard MOR techniques do not apply. The mathematical theory offers some specific alternatives, which however involve a degree of sophistication unjustified in the presence of a few localized nonlinearities. This paper suggests applying standard MOR to the linear parts of the structural system, the interface remaining the original unreduced nonlinear components. A case study focused on the effects of a helicopter land crash is used to exemplify the proposal.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1139-1146
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• 2008

Due to the construction technique (or the construction culture) growth in and out of Korea, newly-developed insulation have been continuously released. Furthermore, all legislation and regulation that World follows are gradually becoming unified. (e.g. FTA(Free Trade Agreement) with the United States was contracted, and inevitable FTA contraction with EU and China). In addition, insulation type, with the purpose are becoming unified. Accordingly, KS F 2803 legislated in 1966 about the Domestic Insulation Standard including traditionally used insulation(Rockwool, Fiberglass, Polystrene, Polyurethan, Perlite) has to be amended by considering International Standard and the alternatives. This reference is going to make description for solution of contradiction.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.136-142
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• 2007

Due to the construction technique (or the construction culture) growth in and out of Korea, newly-developed products have been continuously released. Furthermore, all legislation and regulation that the World follows are gradually becoming unified. (e.g. FTA(Free Trade Agreement) with the United States was contracted, and inevitable FTA contraction with EU and China ), For this reason, it is considered that Korean fire regulation on building interior materials needs to be reviewed and compared with that of international standard so that it becomes legitimate and reasonable one. Especially, this reference is going to make a description of building interior materials' Flame retardant performance standard.

• Imaging Science in Dentistry
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• 제32권3호
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• pp.147-151
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• 2002

Purpose: To compare the standard deviation of gray levels on digital subtracted images obtained by different dental subtraction programs. Materials and Methods: Paired periapical films were taken at the lower premolar and molar areas of the phantoms involving human mandible. The bite registration group used Rinn XCP equipment and bite registration material, based on polyvinyl siloxane, for standardization. The no bite registration group used only Rinn XCP equipment. The periapical film images were digitized at 1200 dpi resolution and 256 gray levels by a flat bed scanner with transparency unit. Dental digital subtraction programs used for this study were Subtractor (Biomedisys Co., Korea) and Emago (Oral Diagnostic Systems, The Netherlands). To measure the similarities between the subtracted images, the standard deviations of the gray levels were obtained using a histogram of subtracted images, which were then analyzed statistically. Results: Subtracted images obtained by using the Emago program without manual selection of corresponding points showed the lowest standard deviation of gray levels (p<0.01). And the standard deviation of gray levels was lower in subtracted images in the group of a bite registration than in the group of no use of bite registration (p < 0.01). Conclusion: Digital radiographic subtraction without manual selection of reference points was found to be a convenient and superior method.

• 한국연초학회지
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• 제23권1호
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• pp.45-52
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• 2001

This study was carried out to evaluate the uncertainty in the analysis of total alkaloids and reducing sugar content in flue-cured tobacco. The sources of uncertainty associated with the analysis of total alkaloids and reducing sugar were the weighing of sample, the preparation of extracting solution, the addition of extracting solution into the sample, the preparation of standard solution, the precision of calibration curve for standard solution, the reproducibility of analysis, and the determination of water content in tobacco, etc. For the calculating uncertainties, Type A of uncertainty was evaluated by the statistical analysis of a series of observation, and Type B by the information based on supplier’s catalogue and/or certificated of calibration. It was shown that the main source of uncertainty was caused by the calibration curve of standard solution, the reproducibility of analysis, the volume measurement of 1$m\ell$, and the purity of nicotine reference material in the preparation of standard solution. The uncertainty in the addition of extracting solution, the sample weighing, the volume measurement of 100$m\ell$, and the determination of water content of tobacco contributed relatively little to the overall uncertainty. The expanded uncertainty of total alkaloids and reducing sugar in flue-cured tobacco at 95% level of confidence was $\pm$0.12% and $\pm$0.54%, respectively.

• 한국조경학회지
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• 제18권3호통권39호
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• pp.23-37
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• 1990

The purpose of this study was to suggest, an ameliorated, 'standard of estimated unit manpower & material' in the Landscape Planting Work. To achieve this goal of this study, following process was performed to reach more advanced results. First, relevant domestic & foreign references were gathered & analyzed with a viewpoint of the system & contents within, Second, most similar foreign country‘s relevant 10 forms & actual site were surveyed, Third, actual site data were collected from the 17 selected landscape Planting sites Fourth, the collected data from reference study & actual site survey were analyzed and calculated. And Finally, analyzed data were reorganized & rearranged in good order with 3 principles to produce more ameliorated 'Standard of estimated unit manpower & material' in the landscape Planting Work. The suggested main results of this study include, 1. Reorganization of current system to transplanting(includes excavation & root ball wrapping), planting(includes tree & shrub), turfing & maintenance 2. Deletion of the Range of 'account of labor' & simultaneous distribution of 'account of labor' with a proposed regular ratio 3. Adjustment of the range of the plant's size 4. Amelioration of the level of 'Account of labor' 5. New establishment in maintenance items as Watering, Fertilizing & spraying chemicals on turf area. 6. Readjustment & new establishment of the backfill volume. 7. Actualization, readjustment & new establishment of the transportation amount.

• 복식문화연구
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• 제13권4호
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• pp.526-539
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• 2005

Recently in the apparel industry, early adolescent girls are emerging as a new consumer group. In response to this, companies are developing clothes, cosmetics, underwear, etc. This study proposed a new size range and size interval for early adolescent girls and presented reference measurements for body parts necessary in designing clothes. For this purpose, a total of 529 girls aged between 10 and 14 were measured and data were collected from 42 anthropometric measurements and 41 photographic measurements per a person. SAS 8.1 was used in data analysis including means, standard deviations, frequency analysis. Based on the results, this study proposed: for Type A - 7 sizes (140A-67, 145A-65, 145A-69, 150A-69, 150A-73, 155A-73, 155A-76): for Type X - 7 sizes (150x-72, 155x-72, 155x-77, 160x-77, 160x-80, 165x-77, 165x-80); and for Type H - 8 sizes (145H-74, 145H-82, 150H-78, 150H-82, 155H-82, 155H-86, 160H-86, 160H-88). Reference measurements suggested for upper garments were 9 items. The outcome of this study may be used as a basic material for adolescent apparel manufacturers to set their apparel sizing system and to supply their consumers, namely, adolescent girls with products fitting their somatotype.

• 분석과학
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• 제19권2호
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• pp.163-171
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• 2006

우리나라 지정폐기물에 함유된 오염물질 분석방법을 제시하기 위해 오니, 폐유, 소각재 등 폐기물 인증표준물질을 확보하여 중금속 종류별 기기별 전처리 방법을 적용 실험하였다. 지정폐기물에 함유된 As, CN, Cd, Cr, Cu, Pb, Hg 7개 항목에 대한 함량시험방법을 제시하였다. 특히, 동일한 전처리 방법이 여러 항목에 적용될 수 있는지를 검토하고, 이들 항목 배출 가능성이 있는 34개 업소 표본사업장을 선정하여 폐기물 시료를 채취하고 제시한 분석방법으로 적용실험을 수행하였다.