• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.693-700
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• 2004

Viscometry was applied to identify irradiated corn starch (CS), sweet potato starch (SS), and potato starch (PS) from non-irradiated controls using Brookfield DV-III programmable rheometer. Effects of starch suspension concentration (7.0-9.5%) and spindle speed (25-125 rpm) were investigated. Established optimal viscosity-measuring conditions showed the highest correlation coefficient between irradiation dose (0-6.0 kGy) and corresponding viscosities for CS, SS, and PS. Threshold values for identifying irradiated starches were suggested. Viscosities of all samples significantly decreased with increasing irradiation dose (p<0.05) and spindle speed, while increased as suspension concentration increased. Optimal conditions for suspension concentration and spindle speed were 7.5% (6.7%, d.b.) and 125rpm in CS, 8.5% (7.3%, d.b.) and 125 rpm in SS, and 9.0% (7.3%, d.b.) and 100rpm in PS, respectively. Under these measuring conditions, threshold values for discriminating unknown samples were 0.313, 0.345, and 0.811 for CS, SS, and PS in 1.5 kGy-irradiated samples, compared with 0.521, 0.798, and 1.693 in non-irradiated samples, respectively, enabling identification of irradiated from non-irradiated starches.

• Journal of Korea Entertainment Industry Association
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• v.15 no.6
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• pp.71-80
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• 2021

This study is aimed at analyzing the characteristics of each service quality and the requirements of the customers followed by the classification of service quality factors of youth sports clubs by using Kano model. For this purpose, a survey was conducted by targeting on 257 subjects in 10 youth sports clubs in Seoul and Gyeonggi areas and for data processing, Microsoft Office Excel 2016 and SPSS 22.0 were used to carry out Frequency Analysis, Factor Analysis, Reliability Analysis, Kano model Quality Classification, Timko's Customer Satisfaction Coefficient, and the computation and analysis of Public-service Customer Satisfaction Index. The following shows the research findings. First, as a result of using Kano model to classify each item of the service quality factors of the youth sports club through Dualistic Quality Theory Attribution, one-dimensional quality elements resulted in all 22 items of service quality factors of youth sports club. Second, the customer satisfaction coefficient computation result showed that satisfaction coefficient appeared by the order of 'kind response of the instructor,'(0.81), 'attitude of the instructor'(0.80), 'systematic lecture program'(0.76), and 'variety of program)'(0.76) and dissatisfaction coefficient appeared by the order of 'clean and pleasant facility'(-0.79), 'attitude of the instructor'(-0.76), 'kind response of the instructor'(-0.76), 'convenience of parking facility'(-0.73), and 'promptness of business process'(-0.73). Third, the public-service customer satisfaction index placing appeared by the order of the 'attitude of the instructor', 'kind response of the instructor', 'clean and pleasant facility' and 'systematic lecture program'.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.717-724
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• 2023

An essential step in evaluating and comparing the performance of two passive radiation dosimeter types, thermosluminescent (TLD) and optically stimulated luminescence (OSL), used by workers in environments with ionizing radiation for individual radiological monitoring and control of external exposure at various times (cumulative dose for 1 month), is to compare the measured dose accuracy, energy response, and coefficient of variation. In fact this performance study consists in determining the accuracy of both R(10) and R(0.07) which are considered as the ratios of the measured dose (Hp(10) or Hp(0.07)) to the delivered dose (Hp(10) or Hp(0.07)) for each photon energy. The validity of the results of this test is based on the acceptance limits of the ICRP and the international standard IEC-62387. The relative energy response used is normalized to the ¹³⁷Cs 662 keV energy to find which energy response is closest to the ideal case, and the coefficient of variation that allows to determine the statistical fluctuation of the Hp(10) and Hp(0.07) doses. The results of the accuracy test for the OSL and TLD dosimeters are acceptable because they fall within the ICRP limits. For the energy response, the OSL performs better than the TLD for Hp(10) and Hp(0.07), and for the coefficient of variation, the OSL satisfies the requirements of ISO 62387 for both Hp(10) and Hp(0.07), while the TLD satisfies these requirements only for the measurement of Hp (0.07).

• Journal of Convergence for Information Technology
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• v.12 no.3
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• pp.141-150
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• 2022

Fluid flow and thermal characteristics of laminar nanofluid(water/Al2O3) flow in a circular U-bend tube have been studied numerically. In this study, the effect of Reynolds number and the solid volume fraction and the impact of the U-bend on the flow field, the heat transfer and pressure drop was investigated. Comparisons with previously published experimental works on horizontal curved tubes show good agreements between the results. Heat transfer coefficient increases by increasing the solid volume fraction of nanoparticles as well as Reynolds number. Also, the presence of the secondary flow in the curve plays a key role in increasing the average heat transfer coefficient. However, the pressure drop curve increases significantly in the tubes with the increase in nanoparticles volume fraction.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.183-183
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• 2018

In this study, 5-bromo-2,9-bis(5,6-diphenyl-1,2,4-triazin-3-yl)-1,10-phenanthroline (5-bromo-Ph4-BTPhen) was synthesized and evaluated for its ability to remove major radionuclides ($Cs^+$, $Sr^{2+}$, and $Co^{2+}$). The synthesized ligand removed both $Sr^{2+}$ and $Co^{2+}$ from $1mg\;L^{-1}$ aqueous solutions with extraction efficiencies of up to 99% at neutral and alkaline pH. The $Sr^{2+}$ and $Co^{2+}$ removal efficiencies decreased as a consequence of the higher bonding strengths of competing metal ions to the N-donor atoms in the cavity of the ligand; competing divalent ions affected the $Sr^{2+}$ and $Co^{2+}$ removal efficiencies more than monovalent ions.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1634-1641
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• 2021

Exposure to gamma-rays is hazardous for humans and other living beings because of their high penetration through the materials. For this reason, shielding materials (usually lead, copper and stainless steel) are used to protect against gamma rays. This study's objective was to prepare ceramic materials for gamma radiation shielding by using different natural bentonite clays. Gamma-ray attenuation performances of the prepared shielding materials at different thicknesses were investigated and evaluated for different gamma-ray energies from different standard point gamma radiation sources (²⁵¹Am, ⁵⁷Co, ¹³⁷Cs, ⁶⁰Co, and ⁸⁸Y). The mass and linear attenuation coefficients of the prepared ceramics vary between 0.238 and 0.443 cm² g^-1 and between 0.479 and 1.06 cm^-1, respectively, depending on their thicknesses. Results showed that these materials could be prioritized because of their evidential properties of gamma radiation protection in radiation applications.

• Journal of dental hygiene science
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• v.15 no.5
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• pp.673-678
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• 2015

The purpose of this study was to evaluate the reliability and accuracy of linear measurements in digital models compared to master model. A master model (ANKA-4; Frasaco GmbH, Tettnang, Germany) with the prepared upper full arch tooth was used. Four linear measurements were recorded between landmarks, directly on the master model and the digital models by a single examiner. Measurements were made with a digital caliper from manual model and with the software from the virtual models. The t-test for paired samples and intraclass correlation coefficient (ICC) were used for statistical analysis. The measurement of two methods showed good reliability. The mean differences between master and digital model were 0.06~0.12 mm. These in vitro studies show that accuracy and reliability of the digital impression is similar to that of the gold standard. Therefore digital impression was also considered to be a acceptable for placement clinically.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.2
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• pp.247-255
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• 2009

This study examined the quality characteristics of brown sauce prepared with rice powder in place of wheat flour, which is the commonly used thickener. With regard to the general components, as the level of rice powder increased and its ratio in the stock increased, moisture decreased and crude protein, lipid, and ash increased. Reducing sugar content was 4.72% in the control group, and as the mixing ratio of stock to rice powder increased from 100:5 (S1) to 100:13 (S5) in the rice powder-added groups, reducing sugar content increased from 3.94% to 4.82%, respectively. In terms of Hunter's color values, as more rice power was added to the beurre mani$\acute{e}$, L, a, and b values increased. Thus, a sauce of a light brown color was appropriately made. For consistency, as more rice powder beurre mani? was inserted into the analyzer, flow was reduced and viscosity significantly increased. The pH of the control (CS) was 4.94, and there were no significant differences between the control and the rice powder-added groups. In sensory evaluations, color presented its highest score as 6.47 when the mixing ratio of stock to beurre mani$\acute{e}$ was 100:7 (S2). S2 also received the highest score for flavor at 6.32. Viscosity was highest in the control (CS) at 6.26, and was not significantly different from the 100:7 (S2) or 100:9 (S3) groups. Finally, the S2 group had the highest scores for taste (6.21) and overall-acceptability (6.30). In correlation analyses between the sensory characteristics, overall-acceptability as well as the color, flavor, viscosity, and taste of the brown sauce all presented comparatively high positive correlations, in which overall-acceptability and color had the highest correlation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2095-2100
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• 2012

In this paper, we propose the channel sounding scheme which is made for ideal communication between some application as well as the short distance of high speed data transmission in MIMO-OFDM system for Wireless PAN. This method is able to perceive the duration of the impulse response through the delaying of power delay profile, modeled a power delay profile which has an attenuate characteristic, and obtained the coefficient of channel response by ML (maximum likelihood). Through the amplitudes, phases and delays associated with each multipath component which were acquired from this channel sounding scheme, we can describe the wave propagation characteristics of channels between the transmitter and receiver so that the receiver could enhance not only the reliability but also the ability of communication link. Multi agent system models can be used to analyze the path of the system within any time frame. Further, parameter values can be perturbed to examine how the path of the system changes in response to exogenous shocks.

• Journal of Radiation Protection and Research
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• v.25 no.4
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• pp.197-205
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• 2000

A prototype electronic dosimeter(PED) adopting a silicon PIN diode detector as a radiation detector has been developed, manufactured and test-evaluated. A radiation signal processing circuit has been electronically tested and then the radiation detection characteristics of this PED has been performance-tested by using a reference photon radiation field. As a result in a electronic performance test, radiation signals from a detector were well observed in the signal processing circuit. The radiation detection sensitivity of this PED after several test-irradiations to $^{137}Cs$ gamma radiation source appeared to be 1.85 cps/$Gy{\cdot}h^{-1}$ with 19.3% of the coefficient of variation, which satisfied the performance criteria for the active personnel radiation monitor. Further improvement of the electronic circuit and operating program will enable the PED to be used in personal monitoring purpose.