• Investigative Magnetic Resonance Imaging
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• v.23 no.4
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• pp.341-350
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• 2019

Purpose: To determine the MR parameters affecting India ink artifacts on opposed-phase chemical shift magnetic resonance (MR) imaging. Materials and Methods: The use of a female Sprague-Dawley rat was approved by our Institutional Animal Care and Use Committee. Using an iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) images, which is a modified Dixon method, axial opposed-phase images of the abdominal cavity were obtained with different MR parameters: series 1, different repetition times (TRs; 400, 2000, and 4000 ms); series 2, different echo times (TEs; 10, 50, and 100 ms); series 3, different field of views (FOVs; 6, 8, 16, and 24 cm); series 4, different echo train lengths (ETLs; 2, 4, and 8); series 5, different bandwidths (25, 50, and 85); and series 6, different slice thicknesses (1, 2, 4, 8, and 16 mm). Artifacts on opposed images obtained with different parameters were compared subjectively by two radiologists. For objective analysis, the thickness of the artifact was measured. Spearman's correlation between altered MR parameters and thicknesses of India ink artifact was obtained via objective analysis. Results: India ink artifact was increasingly apparent using shorter TE, larger FOV and ETL, and thicker slices upon subjective analysis. The objective analysis revealed a strong negative correlation between the thickness of the artifact and TE (r = -0.870, P < 0.01); however, strong positive correlations were found between FOV (r = 0.854, P < 0.01) and slice thickness (r = 0.971, P < 0.01). Conclusion: India ink artifact was thicker with shorter TE, larger FOV, and larger slice thickness.

• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.567-572
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• 2011

A sensitivity analysis of the methods used to evaluate the transport properties of a CdZnTe detector was performed using two different radiations (${\alpha}$ particle and gamma-ray) emitted from an $^{241}Am$ source. The mobility-lifetime products of the electron-hole pair in a planar CZT detector ($5{\times}5{\times}2\;mm^3$) were determined by fitting the peak position as a function of biased voltage data to the Hecht equation. To verify the accuracy of these products derived from ${\alpha}$ particles and low-energy gamma-rays, an energy spectrum considering the transport property of the CZT detector was simulated through a combination of the deposited energy and the charge collection efficiency at a specific position. It was found that the shaping time of the amplifier module significantly affects the determination of the (${\mu}{\tau}$) products; the ${\alpha}$ particle method was stabilized with an increase in the shaping time and was less sensitive to this change compared to when the gamma-ray method was used. In the case of the simulated energy spectrum with transport properties evaluated by the ${\alpha}$ particle method, the peak position and tail were slightly different from the measured result, whereas the energy spectrum derived from the low-energy gamma-ray was in good agreement with the experimental results. From these results, it was confirmed that low-energy gamma-rays are more useful when seeking to obtain the transport properties of carriers than ${\alpha}$ particles because the methods that use gamma-rays are less influenced by the surface condition of the CZT detector. Furthermore, the analysis system employed in this study, which was configured by a combination of Monte Carlo simulation and the Hecht model, is expected to be highly applicable to the study of the characteristics of CZT detectors.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.472-483
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• 2019

This study purposed to analyze how teacher experience of instructional change (EIC), teacher morale (TM), and school climate (SC) mediate or moderate the relationship between teacher efforts on instructional improvement (EII) and teacher efficacy (TE). For the purpose, the 6th year data of Gyeonggi Education Panel Study (GEPS) which was administered in 2017 for the 9th grade students and their teachers from 197 middle schools in Gyeonggi Province was used. As results, the mediation effects of EIC on the link between EII and TE was found only under the innovative climate. The moderation effects of TM on the connection between EIC and TE were appeared in both of the permissive and the innovative climate. Finally, the moderated mediation effects of the TM in the innovative climate were bigger rather than in the permissive climate.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.445-452
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• 2022

The quality and antioxidant characteristics of apios (Apios americana Medikus) according to different harvest periods and steaming treatment were investigated. The quality and antioxidant characteristics of apios were significantly different depending on harvest periods. Total starch contents was higher in 1st harvesting period as 62.32 g/100 g than other harvesting period. The water binding capacity and water solubility index was higher in 1^st harvesting period as 228.65 and 11.29% than other harvesting period. The sucrose and total free sugar contents were 3.64~8.67 and 4.49~9.54 g/100 g, respectively. Total polyphenol and flavonoid contents of apios was the highest 2^nd and 4^th harvesting period at 4.21 mg GAE/g and 611.11 ㎍ CE/g, respectively. DPPH radical scavenging activity was higher in 1st harvesting period as 84.96 mg TE/100 g than other harvesting period, and decreased as the harvest periods were delayed. ABTS radical scavenging activity and ferric-reducing antioxidant power were 43.81~47.89 mg TE/g and 231.20~264.07 mM/100 g, and increased to 50.58~51.44 mg TE/g and 342.55~384.29 mM/100 g after heat treatment. As a result, it is thought that studies on change of quality and physicochemical characteristics according to cultivation characteristics should be preceded for cultivation stability of apios.

• Korean Journal of Exercise Nutrition
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• v.13 no.1
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• pp.37-44
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• 2009

The purpose of this study was to investigate the change of bone metabolic parameters between climbing exercise training and treadmill running training with alpha lipoic acid supplementation in ovariectomized rats. Fifty-six Sparague-Dawley, 8 weeks of age, were assigned into nine groups: normal control at pre-test (Pre-NC), normal control at post-test (NC), sham-sedentary (SS), ovariectomized-control (OVX-Con), ovariectomized-ALA inject (OVX-ALA), ovariectomized-climbing exercise (OVX-CE), ovariectomized-ALA inject+climbing exercise (OVX-ACE), ovariectomized-treadmill exercise (OVX-TE) and ovariectomized-ALA inject+treadmill exercise (OVX-ATE). The climbing exercise group voluntarily climbed the 200 cm tower to drinking water from the bottle set at the top of it. The treadmill exercise group was performed the 60 min treadmill running with grade 6-8%, and velocity 10-15 m/min. The frequency of exercise training was performed 6 days per wk in both training intervention. For the comparison of bone metabolic responses following to different training intervention, the strength, length and weight of femur, total bone density, bone mineral contents, deoxypyridioline, osteocalcin and parathyroid hormone, estradiol and lutenizing hormone were measured in this study. The body weight was higher in the OVX-Con, OVX-ALA and OVX-TE groups as compared to NC group. The total bone mineral density of OVX-ACE showed a higher value than SS, OVX-Con, OVX-ATE and OVX-TE. But urine and blood metabolic parameters showed no significance among groups. In conclusion, this study results suggested that climbing exercise training and alpha lipoic acid supplementation may an effective intervention for prevention of osteoporosis in ovriectomized rats.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.737-744
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• 2015

The purpose of this study was to evaluate the phenolic compounds and radical scavenging activity of the Korean wheat (Triticum aestivum L.) according to germination times. The cultivated varieties were T. aestivum L. cv. Keumkang, Jokyung, Baekjoong, and Goso. The total polyphenol, flavonoid, and tannin contents of the ethanolic extracts of wheat were significantly increased with longer germination times. The total polyphenol contents of ungerminated Keumkang, Jokyung, Baekjoong, and Goso were 13.74, 15.05, 16.84, and 13.02 mg GAE/100 g, respectively, and the contents in germinated wheats increased with longer germination times. The total flavonoid contents of ungerminated wheats were 5.11, 6.72, 6.28, and 5.43 mg CE/100 g, and the total tannin content was 9.19, 8.86, 8.93, and 8.66 mg TAE/100 g, respectively. The total flavonoid and tannin contents were substantially increased with longer germination times. The DPPH radical scavenging activity of ungerminated Keumkang, Jokyung, Baekjoong, and Goso was 30.77, 23.88, 25.35, and 18.73 mg TE/100 g, and the activity in wheats germinated at $25^{\circ}C$ for 72 hours was 47.47, 44.17, 38.22, and 42.85 mg TE/100 g, respectively. The ABTS radical scavenging activity of ungerminated wheats was 3.42, 88.53, 88.87, and 79.97 mg TE/100 g, respectively, and the activity in germinated wheats increased with longer germination times.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.2
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• pp.58-61
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• 2002

Photoluminescence up-conversion in semiconductor heterostructures is a phenomenon in which luminescence occurs at energies higher than that of the excitation photons. It has been observed in many semiconductor heterostructure systems, including InP/AnALAs, CdTe/CdMgTe, GaAs/ordered-(Al)GalnP, GaAs/AIGaAs, and InAs/GaAs. In this wort, GaAs/AIGaAs heterostructures are used as a model system to study the mechanism of the up-conversion process. This system is ideal for testing different models because the band offsets are quite well documented. Different heterostructures are designed to study the effect of disorder on the up-converted luminescence efficiency. In order to study the roles of different types of carriers, the effect of doping was investigated. It was found that the up-converted luminescence is significantly enhanced by p-type doping of the higher-band-gap material.

• Journal of the Korean Institute of Telematics and Electronics
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• v.5 no.1
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• pp.6-12
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• 1968

Experiments have been made on alloys to determine the practicability of using the Peltier effect in a thermoelectric devices. The cooling and heating results of thermoelectrie material coposed of n and p type BiTe are used, whose properties are; , , , , and K: thermal conductivity. The temperature of the cold part has been measured in veccum with respect to the temperature of the hot part. The experiment result agreed fairly with expectation such as was 42 degree C.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.4
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• pp.11-19
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• 1995

In this paper, the Finite Difference Time Domain (FDTD) method is used to analyse the characteristics of the coaxial line transmission coefficent, shielding effectiveness, and compared to results of the moment method. The excitation mode of the Gaussian pulse is assumed to be a TEM-mode instead of the TE or TM-mode and in order to eliminate the reflected wave with in short length of the line. Calculated value of shielding effectiveness of the coaxial line by the FDTD are in good agreement with the results of the moment method.

• Journal of Pharmacopuncture
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• v.16 no.3
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• pp.52-57
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• 2013

Objectives: The main purpose of this research is to investigate the effect of treatment with Hominis Placental pharmacopuncture (HPP) for 32 patients with hemifacial spasm. Methods: We treated facial spasm patients with acupuncture and HPP at Sabaek (ST2), Seung-eup (ST1), Gwallyeo (SI18), Chanjuk (BL2), Sajukgong (TE23), Hagwan (ST7), Hyeopgeo (ST6), Jichang (ST4), Wan-gol (SI4) and Yepung (TE17), and we investigated the effect by using Scott's scale. The data were analyzed by using the SPSS/10.0 for windows program with descriptive statistics, the paired t-test, and the Shapiro-Wilk normality test. Results: After treatment, the grade of the spasm's intensity based on Scott's description were decreased significantly. About 72% of the patients felt that the combination treatment had produced excellent results. Conclusion: These data suggested that HPP can be useful for treating facial spasm patients.