• Journal of Radiation Protection and Research
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• v.39 no.1
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• pp.21-29
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• 2014

A new cold neutron triple-axis spectrometer (Cold-TAS) was recently constructed at the 30 MWth research reactor, HANARO. The spectrometer, which is composed of neutron optical components and radiation shield, required a redesign of the segmented monochromator shield due to the lack of adequate support of its weight. To shed some weight, lowering the height of the segmented shield was suggested while adding more radiation shield to the top cover of the monochromator chamber. To investigate the radiological effect of such change, we performed MCNPX simulations of a few different configurations of the Cold-TAS monochromator shield and obtained neutron and photon intensities at 5 reference points just outside the shield. Reducing the 35% of the height of the segmented shield and locating lead 10 cm from the bottom of the top cover made of polyethylene was shown to perform just as well as the original configuration as radiation shield excepting gamma flux at two points. Using gamma map by MCNPX, it was checked that is distribution of gamma. Increased flux had direction to the top and it had longer distance from top of segmented shield. However, because of reducing the 35% of the height, height of dissipated gamma was lower than original geometry. Reducing the 35% of the height of the segmented shield and locating lead 10cm from the bottom of the top cover was selected. After changing geometry, radiation dose was measured by TLD for confirming tester's safety at any condition. Neutron(0.21 ${\mu}Svhr^{-1}$) and gamma(3.69 ${\mu}Svhr^{-1}$) radiation dose were satisfied standard(6.25 ${\mu}Svhr^{-1}$).

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.1
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• pp.77-85
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• 2013

Purpose: The accurate movement of gantry rotation, collimator and correct application of dose rate are very important to approach the successful performance of Volumetric Modulated Arc Therapy (VMAT), because it is tightly interlocked with a complex treatment plan. The interruption and restart of dose delivery, however, are able to occur on treatment by various factors of a treatment machine and treatment plan. If unexpected problems of a treat machine or a patient interrupt the VMAT, the movement of treatment machine for delivering the remaining dose will be restarted at the start point. In this investigation, We would like to know the effect of interruptions and restart regarding dose delivery at VMAT. Materials and Methods: Treatment plans of 10 patients who had been treated at our center were used to measure and compare the dose distribution of each VMAT after converting to a form of digital image and communications in Medicine (DICOM) with treatment planning system (Eclipse V 10.0, Varian, USA). We selected the 6 MV photon energy of Trilogy (Varian, USA) and used OmniPro I'mRT system (V 1.7b, IBA dosimetry, Germany) to analyze the data that were acquired through this measurement with two types of interruptions four times for each case. The door interlock and the beam-off were used to stop and then to restart the dose delivery of VMAT. The gamma index in OmniPro I'mRT system and T-test in Microsoft Excel 2007 were used to evaluate the result of this investigation. Results: The deviations of average gamma index in cases with door interlock, beam-off and without interruption on VMAT are 0.141, 0.128 and 0.1. The standard deviations of acquired gamma values are 0.099, 0.091, 0.071 and The maximum gamma value in each case is 0.413, 0.379, 0.286, respectively. This analysis has a 95-percent confidence level and the P-value of T-test is under 0.05. Gamma pass rate (3%, 3 mm) is acceptable in all of measurements. Conclusion: As a result, We could make sure that the interruption of this investgation are not enough to seriously affect dose delivery of VMAT by analyzing the measured data. But this investigation did not reflect all cases about interruptions and errors regarding the movement of a gantry rotation, collimator and patient So, We should continuously maintain a treatment machine and program to deliver the accurate dose when we perform the VMAT for the many kinds of cancer patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1242-1248
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• 2013

This study was performed to determine the effects of pretreatment (NT: non-treatment, BTS: boiling treatment with 3% sodium chloride, DTG: dipping treatment in glycerol) and drying methods (sun drying, hot air drying, and cold air drying) on the physicochemical properties and antioxidant activities of dried jujube (Zizyphus jujuba Mill.) fruits. Our results show that moisture content is lower (P<0.05) with DTG, and that moisture content is lower with hot air drying compared to other drying methods. The bulk density was highest with BTS. The soluble solids content was highest with DTG. Additionally, the soluble solids content were highest in the following order: hot air drying> cold air drying> sun drying. The titratable acidity of hot air drying was highest of all the drying methods. The titratable acidity was higher with NT and DTG, and the brix and acid ratio of sun drying was higher than other drying methods. Among the drying methods, BTS showed the best browning-retarding effect, whereas boiling treatment affected quality and color. The total polyphenol content from hot air drying and NT or DTG treatment was relatively higher than the content from BTS. The flavonoid content was highest with BTS, and all dried jujube showed relatively high antioxidant activities. The sensory evaluation results indicated that the organoleptic scores for overall preference were higher in the NT and DTG treatment groups. These results suggest that pretreatment and drying methods affect the quality of dried jujube fruit, and show that glycerol treatment with hot air drying can be applied to the production of high quality dried jujube.

• Analytical Science and Technology
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• v.15 no.5
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• pp.417-426
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• 2002

Inductively Coupled Plasma Dynamic Reaction Cell Quadrupole Mass Spectrometry (ICP-DRC-QMS) was characterized for the detection of the six naturally occurring calcium isotopes. The effect of the operating conditions of the DRC system was studied to get the best signal-to-noise ratio. This experiment shows that the potentially interfering ions such as $Ar^+$, ${CO_2}^+$, ${NO_2}^+$, $CNO^+$ at the calcium masses m/z 40, 42, 43, 44 and 48 were removed by flowing $NH_3$ gas at the rate of 0.7 mL/min $NH_3$ as reactive cell gas in the DRC with a RPq value (rejection parameter) of 0.6. The limits of detection for $^{40}Ca$, $^{42}Ca$, $^{43}Ca$, $^{44}Ca$, and $^{48}Ca$ were 1, 29, 169, 34, and 15 pg/mL, respectively. This method was applied to the determination of calcium in synthetic food digest samples (CCQM-P13) provided by LGC for international comparison. The isotope dilution method was used for the determination of calcium in the samples. The uncertainty evaluation was performed according to the ISO/GUM and EURACHEM guidelines. The determined mean concentration and its expanded uncertainty of calcium was ($66.4{\pm}1.2$) mg/kg. In order to assess our method, two reference samples, Riverine Water reference sample (NRCC SLRS-3) and Trace Elements in Water reference sample (NIST SRM 1643d), were analyzed.

• Journal of Life Science
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• v.30 no.4
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• pp.331-342
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• 2020

The suppression of neuroinflammatory responses in microglial cells can be considered a key target for improving the progression of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). Asparagus cochinchinensis has traditionally been used as a medicine to treat fever, cough, kidney disease, breast cancer, inflammatory diseases, and brain diseases. In this study, we investigated the neuroprotective mechanism of an aqueous extract from A. cochinchinensis root (AEAC), particularly its anti-inflammatory effects on lipopolysaccharide (LPS)-activated BV-2 microglial cells. BV-2 cells were treated with four different concentrations of AEAC. No significant toxicity was detected in BV-2 cells treated with AEAC. Nitric oxide (NO), cyclooxygenase-2 (COX-2) mRNA, and inducible nitric oxide synthase (iNOS) mRNA levels were 21% lower in the AEAC+LPS group than in the Vehicle+LPS group. Lower proinflammatory (TNF-α and IL-1β) and anti-inflammatory cytokine (IL-6 and IL-10) levels were also detected in the AEAC+LPS group than in the Vehicle+LPS group, albeit at varying rates. Moreover, the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group compared to the Vehicle+LPS group, enhancement of the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group, while cell cycle arrest at the G2/M phase caused by LPS treatment was less severe in the AEAC+LPS group. The increase in reactive oxygen species (ROS) generation induced by LPS treatment was also lower in the AEAC-pretreated group than in the Vehicle+LPS group. This is the first study to show that AEAC exerts anti-neuroinflammatory activity against LPS stimulation by regulating the MAPK signaling pathway, the cell cycle, and ROS production.

• Food Science and Preservation
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• v.20 no.5
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• pp.643-649
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• 2013

The antioxidant activity and amino acid composition of various Cheonggukjang extracts, such as the water extract from Cheonggukjang (CWE), the alcohol extract from Cheonggukjang (CEE), the water extract from Cheonggukjang with black garlic (BWE) and the alcohol extract from Cheonggukjang with black garlic (BEE), were examined to investigate the effect of black garlic on the sensory quality and functional properties of Cheonggukjang. The total polyphenol contents of various extracts were 7.03 mg/100 g (BWE), 3.64 mg/100 g (CWE), 2.88 mg/100 g (BEE) and 0.81 mg/100 g (CEE). The radical scavenging activity of the DPPH radical was highest in BWE (91.83%), followed by BEE (37.35%), CWE (25.54%) and CEE (14.80%), in that order. The SOD-like activity was highest in BWE (20.20%), followed by BEE (9.22%), CWE (7.91%) and CEE (6.45%). The thiobarbituric acid reactive substances (TBARS) were highest in BWE (35.18%), followed by BEE (28.33%), CWE (17.40%) and CEE ((14.93%). The total amino acid content of Cheonggukjang (CC) was higher than that of Cheonggukjang with black garlic (CCWB), but the essential amino acid content of CCWB (43.18%) was higher than that of CC (42.27%). The 27 kinds of free amino acid were found in CC, but only 23 kinds were found in CCWB. The L-lysine content was highest (9.23%) in CC, and the L-phenylalanine content was highest (23.14%) in CCWB. The free amino acids (L-threonine, L-serine, L-sarcosine, L-proline, L-alanine, L-valine and D,L-${\beta}$-aminoisobutyric acid) were found in CC but not in CCWB. The ${\gamma}$-amino-n-butyric acid (GABA) was found in CCWB but not in CC. These results suggest that the addition of black garlic has beneficial effects on the functionality of Cheonggukjang without decreasing its sensory characteristics.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.57-63
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• 2009

In this study, seasoning sauces were prepared with Geranium thunbergii sieb. et Zucc. (1%, PGT), Crataegi fructus (1%, PCF) and their combination (0.5% PGT + 0.5% PCF, bPMGC) and then the quality characteristics of the sauces and seasoned pork were investigated. The lightness, redness and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of the sauces were increased by the addition of Crataegi fructus. Sensory qualities such as taste, color and overall acceptability were scored higher in the sauce prepared with Crataegi fructus than the control. The viable cell counts of pork seasoned with the various sauces were 5.04 CFU/g (control), 4.59 CFU/g (PGT), 3.88 CFU/g (PCF) and 4.38 CFU/g (PMGC) after storage for 15 days at $4^{\circ}C$, respectively. The coliform count of the control pork was below 1.0 CFU/g after storage for 25 days and coliform were not detected in PGT, PCF and PMGC after storage for 10 days at $4^{\circ}C$. The thiobarbitunc acid reaotive substance values of PGT, PCF and PMGC were significantly lower than that of control, but volatile basic nitrogen contents were not significantly different between the treated and untreated pork samples during storage. Cooking loss increased in all treatments during storage for 25 days and their water holding capacity increased during storage for 10 days and decreased thereafter. The lightness, redness and yellowness values of PCF were higher than those of the control. The sensory qualities of PCF, including taste, color and overall acceptability, were significantly improved compared to the control. Finally, the pork seasoned with the sauce containing 1% Crataegi fructus extract had significantly improved shelflife, water holding capacity, inhibition of rancidity, color and sensory quality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.1
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• pp.77-88
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• 2000

In this paper, the 3-mode variable gain high power amplifier for a transmitter of INMARSAT-B operating at L-band(1626.5-1646.5 MHz) was developed. This SSPA can amplify 42 dBm in high power mode, 38 dBm in medium power mode and 36 dBm in low power mode for INMARSAT-B. The allowable errol sets +1 dBm as the upper limit and -2 dBm as the lower limit, respectively. To simplify the fabrication process, the whole system is designed by two parts composed of a driving amplifier and a high power amplifier. The HP's MGA-64135 and Motorola's MRF-6401 were used for driving amplifier, and the ERICSSON's PTE-10114 and PTF-10021 for the high power amplifier. The SSPA was fabricated by the RP circuits, the temperature compensation circuits and 3-mode variable gain control circuits and 20 dB parallel coupled-line directional coupler in aluminum housing. In addition, the gain control method was proposed by digital attenuator for 3-mode amplifier. Then il has been experimentally verified that the gain is controlled for single tone signal as well as two tone signals. In this case, the SSPA detects the output power by 20 dB parallel coupled-line directional coupler and phase non-splitter amplifier. The realized SSPA has 41.6 dB, 37.6 dB and 33.2 dB for small signal gain within 20 MHz bandwidth, and the VSWR of input and output port is less than 1.3:1. The minimum value of the 1 dB compression point gets more than 12 dBm for 3-mode variable gain high power amplifier. A typical two tone intermodulation point has 36.5 dBc maximum which is single carrier backed off 3 dB from 1 dB compression point. The maximum output power of 43 dBm was achieved at the 1636.5 MHz. These results reveal a high power of 20 Watt, which was the design target.

• Journal of radiological science and technology
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• v.29 no.1
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• pp.1-6
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• 2006

Purpose: Renal stones are common and typically arise within the collecting system. The renal sinus are contains the collection system, the renal vessels, lymphatcs, fat, and fibrous tissue. Because of the compression of all the large echoes in signal processing, the echo from the renal stone generally cannot be distinguished from large echoes emanating from normal structures of the renal sinus. Use of ultrasonography has been difficult for detecting small renal stone without posterior shadowing and chemical composition of stone. The aim of study was measuring for posterior acoustic shadowing to a stone for various scan parameter and it examines a help in renal stone diagnosis. Material & Methods: The stone was place on sponge examined in a water bath with a 3.5MHz or 7.5MHz transducer(LOGIQ 400, USA). First, tested a variety of gain. Second, tested a variety of dynamic range. Third, tested a variety of focal zone. Fourth, measuring of the echo level for low and high frequency for depth. Results: 1) Average echo level was 98 for low total gain(10 dB) and was 142 for high total gain(40 dB). Posterior acoustic shadowing of renal stone was clear for low gain. 2) Average echo level was 129 for low dynamic range(42 dB) and was 101 for high dynamic range(72 dB). Posterior acoustic shadowing of renal stone was clear for high dynamic range. 3) When stone is in focal zone of transducer, definite posterior acoustic shadow is identified. 4) Stone was clear appeared for high frequency(7.5 MHz) than low frequency(3.5 MHz) and it is not distorted. Conclusion: The demonstration of an posterior acoustic shadow of renal stone dependents on several technical factors such as gain, dynamic range, focus, and frequency. This various factors are a help in renal stone diagnosis.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.567-573
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• 2017

The purpose of this study was to evaluate whether or not there was artifact when the upper limb could not be lifted to the top of the head during multi-detector computed tomography(MDCT) scans of the chest and abdomen. Contrast radiography of the human and chest phantom was performed with 128channal MDCT. Under the same conditions(120 kVp, 110 mAs, standard algorithm)both hands lifted up and put down each time in the human experiment. In the chest phantom experiment, the radiography was carried out when the upper limb phantom was adjusted at a certain distance(0, 3, 7 cm) from the chest phantom. Subsequently, the values of Noise, CT number, SNR, and CNR were measured in the field of concern. The noise value of fat, rib, and muscle increased when the arm was lifted in humans(0.79, 47.8, 27%). Furthermore, when the upper limb was lowered, the noise value of muscle and lung increased in the phantom(31.2, 9.4%). In addition, the noise value of the muscles and lung decreased by 5, 25.12% and 5.6, 15.35% as the upper limb moved about 0,3,7cm away from the chest. When the chest and abdominal radiography were performed, in the case of the presence of other parts outside the inspection area, the probability of artifact was minimal while the distance was more than 3cm away from the upper limb to the chest and abdomen.