• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.107-112
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• 1990

Chromatograms of asphalt cements were observed using high pressure - gel permeation chromatography (HP-GPC). The chromatogram characterzed profile of molecular size distribution of asphalt cements. Bituminous concretes using the asphalt cements were prepared in laboratory to measure mechanical properties, tensile strength (TS) and resilient modulus (MR), in dry and wet conditions. Three sources of AC-20 Asphalt cements and one aggregates were used for GPC test and strength test. Results of mechanical property tests and GPC tests were analyzed to evaluate correlation between those two results. Regression analysis showed strong correlation between a mechanical property and sliced percent areas of GPC profile. Mathematical models were developed for estimating mechanical properties of asphalt cement concrete based on HP-GPC data.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.5
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• pp.26-43
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• 2000

It is well accepted that gloss variation deteriorates the print quality and there are various objective ways to measure this. Several studies now have shown that the coefficient of variation in the octave band passed printed gloss image has an excellent correlation with ratings by an expert panel using a magnitude estimation scaling method. The correlation improves when the gloss level is also taken into account beyond that of the COV. There is also evidence that the correlation would improve even more if the gloss spatial distribution could be better accounted for. We show that much (at least 80% and perhaps up to 90%) of the gloss distribution can be accounted for by the paper topography over a wide range of dimensions (scale). Recent work has supported the role that microroughness and multiple surface scattering play in the gloss distribution. This offers the promise of showing that even a greater amount of gloss variationcan be explained by topography.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.296-297
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• 2013

We have investigated correlation between airtightness measured by blower door and airborne sound insulation measured in the upper and lower units. We consist of two cases : all windows sealed(CASE 1) and not sealed(CASE 2). As a result, CASE 1 is tighter than CASE 2 in airtightness, but CASE 1 is lower than CASE 2 in sound level difference. This is because of big wind on measuring CASE 1. Thus we are going to measure them at another fields considering this factor. Finally we ought to find out the correlation between airtightness and sound insulation.

• Journal of the Semiconductor & Display Technology
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• v.16 no.4
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• pp.52-58
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• 2017

In this study, we tried to analyze and measure the correlation between the part dimensional tolerance empirically applied by the designer and the final performance of the equipment, which is expressed as the pressing pressure uniformity. For this purpose, the dimensional tolerances and pressing pressure uniformity of eight laminator equipments were measured actually. As a result of the correlation analysis, it was confirmed that the tolerance grade for each dimension determined by the designer was valid. In the case of laminator equipment, the driving parts and the flatness have the largest influence on the uniformity of the pressing pressure.

• Journal of Multimedia Information System
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• v.9 no.2
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• pp.161-170
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• 2022

Under General anesthesia with isoflurane, we insert a chicken's esophageal catheter into the near the left atrium. 1MHz radio wave was added to electrocardiogram electrodes of the esophagus, and the change of impedance (phase) was obtained by amplitude synchronous detection technique. At the same time, a thin tube is surgically inserted into the axillary artery to continuously measure blood pressure. The correlation between impedance (phase) and blood pressure was obtained. Both showed a very high correlation (R²=0.9665). It was also observed the waveform flowing from the left atrium into the left ventricle. When an individual infected with the avian influenza virus develops, the cytokine storms lead to hypotension earlier than the test for antigen-antibody reaction. In order to detect this, in the future, this impedance technique will be useful for screening individuals infected with avian influenza virus by measuring the blood pressure of chickens in cages in a non-contact manner using microwaves.

• Journal of Korea Multimedia Society
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• v.25 no.9
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• pp.1307-1315
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• 2022

In this paper, we proposed and developed a new portable skin elasticity measuring device based on the indentation method using piezoelectric effect. The proposed device is designed to minimize the uncertainty caused by the layer structure of the skin when measuring the elasticity of the skin. And, we developed a piezoelectric-based thin-film pressure sensor that can measure quantitatively and quickly during repeated measurement as a device sensor. To confirm the effectiveness of the proposed measuring device, it was compared with the experimental results of the conventional measuring devices under the same experimental conditions, and statistical correlation analysis was performed between the experimental data of the proposed measuring device and the experimental data of the conventional measuring devices. As a result of the correlation analysis, it was confirmed that the proposed measuring device had a high correlation with the conventional measuring devices. Therefore, it was confirmed that the proposed skin elasticity measuring device was effective.

• Journal of Korean society of Dental Hygiene
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• v.15 no.3
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• pp.389-397
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• 2015

Objectives: The purpose of the study is to examine the behaviors by the degree od dry mouth related to stress, dry mouth and halitosis. Methods: The subjects were 400 adults. A self-reported questionnaire was completed from August 1 to November 30, 2014. The data were analyzed using SPSS 18.0 program. The questionnaire consisted of eight questions of general characteristics of the subjects, one question of subjective stress symptom, six questions of dry mouth symptom, four questions of dry mouth behavior, and one question of halitosis. Results: There was a significant difference between halitosis and stress in patients having systemic diseases. Stress had a significant difference with gender, income, drinking frequency and alcohol consumption. The degree of dry mouth had a significant difference with gender and age. In dry mouth severity, behavior showed a significant difference with age, education, and times and amount of alcohol consumption. Age had a positive correlation with cigarette consumption and a negative correlation with dry mouth and dry mouth behavior. Cigarette consumption showed a positive correlation with alcohol consumption. Drinking frequency had a positive correlation with alcohol consumption, dry mouth, dry mouth behavior, halitosis and stress. Alcohol consumption had a positive correlation with dry mouth behavior, and dry mouth showed a positive correlation with dry mouth behavior, halitosis and stress. Dry mouth behavior had a positive correlation with halitosis and stress, while halitosis showed a positive correlation with stress. Conclusions: Stress, dry mouth and halitosis were closely correlated. Since stress is the most important variable, stress relief will be the most effective measure to alleviate oral symptoms. Therefore, stress relief measures need to be devised for oral health management in adults having stressful life.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3284-3292
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• 2013

The purpose of this study was to translate QUEST 2.0 in Korean with valid translation process and to measure psychometric characteristics. Translation process was consist of six steps. Internal consistency was analyzed by Cronbach's ${\alpha}$. Test-Retest reliability was analyzed by Spearman Rank Correlation Coefficient. Internal consistency of 'Assistive device' was .88, 'Services' .92. There was no statistically significant difference according to repetitive measure. The spearman correlation coefficient was .64 for "Assistive Device" and .66 for "Services". This result reflects K-QUEST 2.0's (Korean-Quebec User Evaluation of Satisfaction Assistive Technology 2.0) safety, consistency, and predictability in aspect of measure. In this study, the K-QUEST 2.0 was translated into Korean and the reliability of K-QUEST 2.0 was tested. Decisively, the K-QUEST 2.0 can be applied to evaluate user satisfaction of assistive technology.

• Journal of Astronomy and Space Sciences
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• v.28 no.3
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• pp.173-181
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• 2011

Korea Astronomy and Space Science Institute researchers have installed and operated magnetometers at Mt. Bohyun Observatory to measure the Earth's magnetic field variations in South Korea. We, in 2007, installed a fluxgate magnetometer (RFP-523C) to measure H, D, and Z components of the geomagnetic field. In addition, in 2009, we installed a Overhauser proton sensor to measure the absolute total magnetic field F and a three-axis magneto-impedance sensor for spectrum analysis. Currently three types of magnetometer data have been accumulated. In this paper, we provide the preliminary and the first statistical analysis using the BOH magnetometer installed at Mt. Bohyun Observatory. By superposed analysis, we find that daily variations of H, D, and Z shows similar tendency, that is, about 30 minutes before the meridian (11:28) a minimum appears and the time after about 3 hours and 30 minutes (15:28) a maximum appears. Also, a quiet interval start time (19:06) is near the sunset time, and a quiet interval end time (06:40) is near the sunrise time. From the sunset to the sunrise, the value of H has a nearly constant interval, that is, the sun affects the changes in H values. Seasonal variations show similar dependences to the sun. Local time variations show that noon region has the biggest variations and midnight region has the smallest variations. We compare the correlations between geomagnetic variations and activity indices as we expect the geomagnetic variation would contain the effects of geomagnetic activity variations. As a result, the correlation coefficient between H and Dst is the highest (r = 0.947), and other AL, AE, AU index and showed a high correlation. Therefore, the effects of geomagnetic storms and geomagnetic substorms might contribute to the geomagnetic changes significantly.

• Analytical Science and Technology
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• v.26 no.2
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• pp.120-124
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• 2013

It was studied to analyze the $CO_2$, CO, $SO_2$ standard gases of combustion gases by the open path FT-IR spectrometer with passive mode for remote analysis of air pollutant and volcano gases without IR lamp. As result, it was confirmed to have good linearity with more than 0.9 as correlation coefficients on the calibration curve of $CO_2$, CO concentration by MLR method. But in the case of $SO_2$, because the correlation coefficients were 0.88, the linearity could be lower. Finally, the concentration of three gases was predicted on in-site fire experiment under the condition of quantitative analysis. It could measure high $CO_2$ concentration as predicted result, but didn't measure the CO and $SO_2$. According to the result, it was possible to measure the combustion gases to long distance by only open path FT-IR spectrometer without infrared lamp.