• The Journal of the Korea Contents Association
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• v.21 no.5
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• pp.996-1003
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• 2021

The purpose of this study is to evaluate the reliability of repeated measurements of several dental scanners. Blue-lighted scanners, white-light scanners and optical-type scanners are used in the study of repeatability in this study. The measurement results were calculated as root mean square (RMS) and the significance level was confirmed by applying the 1-way ANOVA statistical technique (𝛼=.05). According to the statistical analysis, the scanner with the largest RMS value was Z-opt group (38.2 ㎛. Next, D-white was 35.2 ㎛ and the group with the lowest RMS value was I-blue (34.1 ㎛). The comparison of RMS means between each group was not significant (p>.05). From this result, the blue light had the lowest error in repeatability of dental scanners, but no statistical significance. The conclusion of this study is that the study results are clinically acceptable.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.42-52
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• 2008

Purpose: Resonance Frequency Analysis(RFA) technique can be used as an effective method in measuring the implant stability and documenting the clinical results. This technique also determines how stable the implant is before performing a prosthetic practice. Having become one the guidelines of the implant therapy whose final objective is the immediate loading, the $Osstell^{TM}$ mentor is giving a lot of information to the clinicians recently. In this communication, experiments were performed to investigate how reliable the measured ISQ values by $Osstell^{TM}$ mentor are, and to see if those are also stable even after sterilization. As five objectives: 1) How stable measured ISQ values after fixation $Smartpeg^{TM}s$ for 400 times. 2) How stable measured ISQ values after 'attach-detach'$Smartpeg^{TM}'s$ for 400 times. 3) How stable measured ISQ values after clinical sterilization methods. 4) How stable measured ISQ values after repeatedly sterilization in autoclave for 10 times. 5) What is the critical temperature which is lost the magnetism of $Smartpeg^{TM}$. Materials and Methods: Clinical sterilization methods(Autoclave sterilization, Dentistar sterilization, Ultra violet sterilization, Vacuum dry unit sterilization, Boiling water sterilization, combined $H_{2}O_{2}$ and Alcohol sterilization).$Smartpeg^{TM}s$. D3 Block bone($3{\times}9{\times}2cm$). Osstem implant(${\emptyset}4.1$-10mm).$Osstell^{TM}$ mentor. Individual experiment was used 8 number of $Smartpeg^{TM}s$ and they had measured to ISQ values of before experiment and after experiment. Results: 1. The measured ISQ values did not change after fixation $Smartpeg^{TM}s$ for 400 times. 2. There was no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ for 400 times. 3. The measured ISQ values did not change after the usual clinical sterilization methods. 4. The measured ISQ values did not change after sterilization in autoclave for 10 times. 5. It was impossible to exactly measure the critical temperature which is lost the magnetism of $Smartpeg^{TM}s$. But, the results was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10 minute. Conclusion: The measured ISQ values showed insignificant differences in case of no changes in the magnetism of the $Smartpeg^{TM}s$. It seems that the $Smartpeg^{TM}s$ can be used repeatedly in every measurement if the original magnetisms of the $Smartpeg^{TM}s$ can be recognized. There seems to be no significant changes in the measured ISQ values of 'attach-detach $Smartpeg^{TM}s'$ only if the screw pitches were unimpaired. The clinical sterilization methods seems acceptable because the result was resulted to lost its magnetism in higher temperature than $150^{\circ}C$/10minute.

• Restorative Dentistry and Endodontics
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• v.35 no.4
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• pp.246-256
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• 2010

The purpose of this study was to evaluate a rotational stability of endodontic electronic motors by comparing the changes of rotational speed, depending on the number of usages and with/without static load. Twelve new endodontic electronic motors were used in this study. Non contact type digital tachometer was used for measuring the rotational speed of handpiece. True RMS Multimeter was used for measuring the voltages and the electric currents. All measurements were recorded every 10 seconds during 10 minutes and repeated 9 times. Five repetition was done per each electronic motor. To statistical analysis, student t-test, repeated measures and Scheffe's post-hoc tests were performed. In the same motor group, there was no significant difference in all measurements. In all groups, there was no significant difference in the amount of rotational speed changes depending on the number of usages and with/without static load. In the limitation of this study, the results showed that all kinds of endodontic electronic motors in this study had an established rotational stability. Therefore they could be safely used in root canal treatment with a reliable maintenance of rotational speed, regardless of the number of usages and with/without load.

• Industry Promotion Research
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• v.6 no.3
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• pp.19-24
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• 2021

There should be no problem in the measurement system for scientific quality management. In this paper, we want to correctly identify the factors that can affect the measurement results during the measurement process and identify what causes them when the measurement results cause problems in terms of location and variation. Variations in the measurement system are largely described in terms of location and dispersion. Location-related attributes are accuracy, stability, and linearity while dispersion-related attributes are reproducibility and repeatability. Analyzing the factors associated with dispersion is an R&R analysis, in which the size of repeatability and reproducibility is represented by a range of differences between multiple measurements and a range of differences between measurements, and 99% of dispersion is determined. Experimental design can also be used for measurement system analysis. Proper analysis is performed only when the factors causing the fluctuation, the worker and the product, are correctly identified as random or fixed factors.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.732-735
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• 1988

Flavor stability of cooking oils such as rice bran oil, double fractionated palm olefin and soybean oil were determined by headspace analysis using gas chromatography. In the headspace, the contents of volatile compounds, oxygen and hydrogen were measured. The hydrogen content in the headspace correlated well with the contents of volatile compound (r > 0.95). Therefore, it is proposed that a single measurement of hydrogen and oxygen is used as a index of flavor stability of cooking oils instead of separate measurement of volatile compounds and oxygen. which have conventionally been used.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.143-150
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• 2007

Purpose : This study was conducted to validate enzyme immunoassay (EIA) for the quantitative measurement of human IgG antibodies specific for Haemophilus influenzae type b (Hib) capsular polysaccharide. Method : We evaluated specificity, repeatability, intermediate precision, accuracy, lower limit of quantification (LLOQ), and stability to validate standardized EIA for the quantitative measurement of human anti-polyribosylribitol phosphate (PRP) IgG antibodies. Results : The results indicated that this EIA showed specificity to HbO-HA antigen and repeatability and intermediate precision were within acceptance criteria (repeatability: $CV{\leq}15%$, intermediate precision: $CV{\leq}20%$). The EIA-derived results from this laboratory were equivalent to those obtained by the standard radioactive antigen binding assay (RABA) for quantitation of anti-PRP antibodies in the 28 sera. Spiking recovery result was within acceptance criteria ($100{\pm}20%$). The precision and accuracy of samples in LLOQ were from -14.7 to -4.7% in nominal values, which were within acceptance criteria (precision: $CV{\leq}25%$, accuracy: ${\pm}25%$). Freeze-thaw stability and short term temperature stability were within ${\pm}20%$ of acceptance criteria. Conclusions : The EIA which is performed at the Center for Vaccine Evaluation and Study Ewha Medical Research Institute, is an appropriate serologic assay which can be used for quantitation of anti-PRP IgG antibodies in human sera.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.465-470
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• 1991

In order to investigate the thermal and oxidative stability of different frying oils including soybean oil, palm oil, two blended oils of soybean-palm (5 : 5 and 7 : 3) and shortening, physico-chemical properties such as acid value, peroxide value, TBA value, degree of coloring, refractive index and specific gravity of the frying oils were measured during the preparation of French fried potatoes by repeated frying. The instability of soybean oil against thermal and oxidative degradation could be lessened by using blended oils in which the ratio of palm oil to soybean oil is more than 50%.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.728-732
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• 2004

Convenient method for determination of egg white foaming properties was suggested. Highly reproducible results were obtained when 70g egg white was whipped at 1,200 rpm for 2 min. Using standardized testing method, foaming capacity and stability of egg white samples including fresh egg white, freeze-dried egg white and commercial egg white powder were effectively differentiated. Foaming capacity of egg white was not affected during storage of fresh egg white up to 4 weeks at $4^{\circ}C$, whereas foaming stability significantly decreased after 2 weeks of storage.

• Science of Emotion and Sensibility
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• v.3 no.1
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• pp.63-71
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• 2000

본 연구에서는 20대의 건강한 남자대학생 45명을 대상으로 작업조건(안정상태, 연산작업상태, 휴식상태, 반복연산작업상태, 연산작업후 아정상태)과 연산레벨(연산작업의 난이도)에 따른 생리신호의 측정을 위한 실험 프로토콜을 제안하고 측정된 생리신호에 대한 분석을 하였다. 연산작업에 대하여 측정된 파라메터에 대하여 1) 정규분포화를 위한 파라메터의 변환 2) 파라메터간의 산관관계의 조사 3) 연산작업에 대한 파라메터의 표준화 4) 작업조건과 연산레벨에 대한 파라메터의 차이에 대한 유의성검정을 하여 연산스트레스를 평가할 수 있는 파라메터를 추출하였다. 연산작업시의 파라메터는 안정산태의 파라메터와 유의적인 차이를 나타내어 연구에 사용된 연산작업이 생리신호의 변화를 발생시키는 것으로 밝혀졌고 연산작업후의 휴식상태에서 측정된 대부분의 파라메터의 갓이 연산작업전의 안정상태의 파라메터의 통계적으로 유의적인 차이가 없어서 본 연구에 사용된 연산작업은 단기적 스트레스를 유발하는 것으로 밝혀졌다. 그리고, 동일한 연산레벨에 대한 연산작업을 반복하더라도 파라메터의 값은 처음으로 연산작업을 할 때의 파라메터의 값과 유의적인 차이가 없었다. 그러나, 연산레벨에 따라서는 Heart Rate, HRV의 LF/HF, HRV의 MF/(LF+HF), Return Map의 분산, 코끝의 Mean Temperature, GSR-Mean과 호흡수는 차이가 있는 것으로 밝혀졌다. 따라서 이들 파라메터를 사용하면 연산스트레스의 강도를 지수화할 수 있을 것이다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.1011-1017
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• 2010

Sunflower oil (SO), canola oil (CO) and frying oil (FO) were used as edible oils in this study. According to the frying number, the extracted oils from French fried potatoes were used as experimental samples. To investigate the relationship between the change of fatty acid composition and the stability of the lipid oxidation during frying, the changes of fatty acid composition and the degree of the lipid oxidation of samples were examined. Acid values and peroxide values were evaluated as the degree of lipid oxidation. The acid values of CO and FO were increased with the frying times. The increased acid values of CO and FO were 0.20 and 0.17 on the basis of initial value at 30 times, respectively, but the acid value of SO was lower than those of CO and FO. The peroxide values of the samples were not increased uniformly with the frying number. As the number of frying times was increased, the fatty acid composition of SO and FO were changed. Namely, the oleic acid composition was decreased, whereas the linoleic acid composition was increased with the number of frying times. The benzo(a)pyrene contents of the extracted oils from French fried potatoes did not change regularly as the frying times was increased.