• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.120-129
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• 2020

In Yesan-gun, Korea's main apple-producing region, the area of apple cultivation and yield are declining. In particular, the worsening quality of fruits due to unusually high temperatures amid recent climate change has also become a major challenge for apple orchards located on flatlands. The objective of this research is to investigate quality changes of apples according to different growing environments, depending on the shade of the sun, by covering the trees with different colors of wind nets. A white and blue wind nets with a hole size of 2 × 2 mm is installed on two experimental trees, 17-year-old 'Fuji' and 'Hongro', which are planted 1.5 m × 3.5 m in the north-south direction. Treatment of wind nets effectively lowered fruit surface temperature regardless of apple variety. When measuring the temperature of the fruit surface at 2 pm, the temperature of the air was 34.8℃, but the 'Fuji' of the untreated blocks was the highest at 40.0℃, while the blue wind net and the white wind net were significantly lower at 34.9℃ and 36.6℃, respectively. In 'Hongro', the results showed that the surface temperature was effectively lowered by recording 38.3℃ for the blue wind net and 38.5℃ for the white wind net treatment when the untreated one was 44.2℃. According to the color difference in 'Fuji', the skin redness (a^⁎) was the lowest with untreated control at 16.5, but the blue and white wind net treatment higher at 18.0 and 19.3, respectively. In 'Hongro', the white wind net treated fruit also showed a much higher skin redness than the untreated control of 28.1, showing much higher a^⁎ of 34.9. Sunburn damage in 'Fuji' apples amounted to 9.4% in untreated control. However, the blue and white wind net treatment revealed to 3.8% and 4.2%, respectively. In 'Hongro', those damage in the fruits treated with blue or white wind net, accounted for only 8.8% and 12.4%, respectively, significantly lower than 28.8% occurrence of untreated one. And, these results were understood to be the result of low UV radiation being blocked by the treatment of wind nets.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.264-272
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• 1979

The flat-plate and tubular soar collectors were designed and constructed for drying the rough rice, and the performance of the collectors and drying effect were investigated when rough rice was packed in grain bin connected to collectors. Average-monthly radiation on a horizontal surface based on bright sunshine in Daejeon area during 1978 was the highest as $16,814\;KJ/m^2{\cdot}day$ in May and the lowest as $4,254\;KJ/m^2{\cdot}day$ in December, and significane was not recognized between the calculated and recorded values. The thermal effciency of collectors were increased as radiation increased during drying period and the average thermal effciency of flat-plate and tubular collectors in 11 to 12 o'clock a.m were 28.12 and 16.75%, respectively. The average inlet temperature of grain bin at 12 o'clock was shown as 20.02 at control 40.5 at grain bin connected to tubular collector and $55.1^{\circ}C$ at grain bin connected to flat-plate collector. In 25 cm rough rice depth in grain bin, tim taken for drying from initial moisture content at 27.4 to decrease upto 17.0% (14.5 % on wet basis) were 32 in control, 18 in grain bin connected to tubular collector and 11 hrs to flat-plate collector, and grain depth influenced drying rate remarkably. In the view point of drying characteristics, drying pattern showed initially falling-rate to constant-rate period finally.

• Radiation Oncology Journal
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• v.9 no.2
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• pp.215-219
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• 1991

To evaluate the effect of MVP chemotherapy and hyperfractionated radiotherapy in Stage III unresectable non small cell lung cancer (NSCLC), authors have conducted a prospective randomized study since January 1991, Stage IIIa or IIIb unresectable NSCLC patients were treated with hyperfractionated radiotherapy (120 cGy/fx BID) up to 6500 cGy following 3 cycles of induction MVP (Mitomycin C 6 mg/$m^2$, Vinblastine 6 mg/$m^2$, Cisplatin 60 mg/$m^2$) and randomized for either observation or 3 cycles of maintenance MVP chemotherapy. Until August 1991, 18 patients were registered to this study. 4 cases were stage IIIa and 14 were stage IIIb. Among 18 cases 2 were lost after 2 cycles of chemotherapy, and 46 were analyzed for this preliminary report. The response rate of induction chemotherapy was $62.5\%$ : partial response, $50\%$ and minimal response, $12.5\%$. Residual tumor of the one partial responder was completely disappeared after radiotherapy. Among 6 cases who were progressed during induction chemotherapy, 4 of them were also progressed after radiotherapy. All patients were tolerated BID radiotherapy without definite increase of acute complications, compared with conventional radiotherapy group. But at the time of this report, one patient expired in two month after the completion of the radiotherapy because of treatment related complication. Although the longer follow up is needed, authors are encouraged with higher response rate and acceptable toxicity of this treatment. Authors believe that this study is worthwhile to continue.

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.21-34
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• 2017

The ground penetrating radar (GPR) signal can be measured with different amplitudes according to the directivity, so the directivity of the antenna should be considered. The objective of this study is to investigate the directivity of antenna by analyzing the reflection characteristics of electromagnetic waves radiated from the antenna, and to evaluate effective range of angle that can inspect an abnormal area according to the directivity of antenna. For the measurement of the directivity, a circular metal bar is used as reflector and the signals are measured by changing the angle and the distance between reflector and antenna in the E- and H-plane. The boundary distance between the near field and the far field is determined by analyzing the amplitudes of reflected signals, and two points with different distances from each of near and far fields are designated to analyze radiation patterns in near and far fields. As a result of radiation pattern measurement, in the near field, minor lobes are observed at angle section at more than $50^{\circ}$ in both E- and H-plane. Therefore, antenna has the directivity for the direction of main lobe and minor lobes in near field. In the far field, antenna has the directivity for a single direction of main lobe because minor lobes are not observed. The amplitude of the signal reflected from the near field is unstable, but it can be distinguished from noise. Therefore, in the near field, the ground anomaly can be detected with high reliability. On the other hand, the amplitude of the signal reflected from the far field is stable, but it is hard to distinguish between reflected signal and noise because of the excessive loss of electromagnetic wave. The analyses of directivity in the near and the far fields performed in this study may be effectively used to improve the reliability of the analyses of abnormal area.

• Progress in Medical Physics
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• v.23 no.1
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• pp.15-25
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• 2012

The aim of this study is to evaluate plan quality and dose accuracy for Volumetric Modulated Arc Therapy (VMAT) on the TG-119 and is to investigate the effects on variation of the selectable optimization parameters of VMAT. VMAT treatment planning was implemented on a Varian iX linear accelerator with ARIA record and verify system (Varian Mecical System Palo Alto, CA) and Oncentra MasterPlan treatment planning system (Nucletron BV, Veenendaal, Netherlands). Plan quality and dosimetric accuracy were evaluated by effect of varying a number of arc, gantry spacing and delivery time for the test geometries provided in TG-119. Plan quality for the target and OAR was evaluated by the mean value and the standard deviation of the Dose Volume Histograms (DVHs). The ionization chamber and $Delta^{4PT}$ bi-planar diode array were used for the dose evaluation. For treatment planning evaluation, all structure sets closed to the goals in the case of single arc, except for the C-shape (hard), and all structure sets achieved the goals in the case of dual arc, except for C-shape (hard). For the variation of a number of arc, the simple structure such as a prostate did not have the difference between single arc and dual arc, whereas the complex structure such as a head and neck showed a superior result in the case of dual arc. The dose distribution with gantry spacing of $4^{\circ}$ was shown better plan quality than the gantry spacing of $6^{\circ}$, but was similar results compared with gantry spacing of $2^{\circ}$. For the verification of dose accuracy with single arc and dual arc, the mean value of a relative error between measured and calculated value were within 3% and 4% for point dose and confidence limit values, respectively. For the verification on dose accuracy with the gantry intervals of $2^{\circ}$, $4^{\circ}$ and $6^{\circ}$, the mean values of relative error were within 3% and 5% for point dose and confidence limit values, respectively. In the verification of dose distribution with $Delta^{4PT}$ bi-planar diode array, gamma passing rate was $98.72{\pm}1.52%$ and $98.3{\pm}1.5%$ for single arc and dual arc, respectively. The confidence limit values were within 4%. The smaller the gantry spacing, the more accuracy results were shown. In this study, we performed the VMAT QA based on TG-119 procedure, and demonstrated that all structure sets were satisfied with acceptance criteria. And also, the results for the selective optimization variables informed the importance of selection for the suitable variables according to the clinical cases.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.360-371
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• 2018

Extracts and fractions of Anemarrhena asphodeloides Bunge were prepared and their physiological activities and components were analyzed. Antimicrobial activities of the ethyl acetate and aglycone fractions were $78{\mu}g/ml$ and $31{\mu}g/ml$, respectively, for Staphylococcus aureus and $156{\mu}g/ml$ and $125{\mu}g/ml$, respectively, for Pseudomonas aeruginosa. 1,1-Diphenyl-2-picrylhydrazyl free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction, and aglycone fraction of A. asphodeloides extracts were $146.2{\mu}g/ml$, $23.19{\mu}g/ml$, and $71.06{\mu}g/ml$, respectively. The total antioxidant capacity ($OSC_{50}$) in an $Fe^{3+}$-EDTA/hydrogen peroxide ($H_2O_2$) system were $17.5{\mu}g/ml$, $1.5{\mu}g/ml$, and $1.4{\mu}g/ml$, respectively. The cytoprotective effect (${\tau}_{50}$) in $^1O_2$-induced erythrocyte hemolysis was 181 min with $4{\mu}g/ml$ of the aglycone fraction. The ${\tau}_{50}$ of the aglycone fraction was approximately 4-times higher than that of (+)-${\alpha}$-tocopherol (${\tau}_{50}$, 41 min). Analysis of $H_2O_2$-induced damage of HaCaT cells revealed that the maximum cell viabilities for the 50% ethanol extract, ethyl acetate fraction, and aglycone fraction were 86.23%, 86.59%, and 89.70%, respectively. The aglycone fraction increased cell viability up to 11.53% at $1{\mu}g/ml$ compared to the positive control treated with $H_2O_2$. Analysis of ultraviolet B radiation-induced HaCaT cell damage revealed up to 41.77% decreased intracellular reactive oxygen species in the $2{\mu}g/ml$ aglycone fraction compared with the positive control treated with ultraviolet B radiation. The findings suggest that the extracts and fractions of A. asphodeloides Bunge have potential applications in the field of cosmetics as natural preservatives and antioxidants.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.4
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• pp.309-318
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• 2011

In this study, the antioxidative effect, antibacterial, inhibitory effects on tyrosinase, inhibitory effects on elastase and component analysis of Phellinus linteus (P. linteus) extracts were investigated. The ethyl acetate fraction of P. linteus extracts ($2.94\;{\mu}g/mL$) showed the highest free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$). Reactive oxygen species (ROS) scavenging activity ($OSC_{50}$) of P. linteus extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system was investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction ($0.0072\;{\mu}g/mL$) showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of P. linteus extracts on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The P. linteus extracts showed cellular membrane protective effects in a concentration dependent manner ($5{\sim}50\;{\mu}g/mL$). The inhibitory effect ($IC_{50}$) on tyrosinase of P. linteus extract was the highest at 50 % ethanol extract ($6.34\;{\mu}g/mL$), and the inhibitory effect ($IC_{50}$) on elastase of P. linteus was the highest at ethyl acetate fraction ($14.08\;{\mu}g/mL$). TLC, HPLC chromatogram and LC/ESI-MS of the ethyl acetate fraction obtained from P. linteus extracts were identified interfungin A (PL RPT-1a). These results indicate that extract/fractions of P. linteus can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging ROS, and protect cellular membranes against ROS. Extract/fractions of P. linteus can be applicable to new cosmeceuticals for antioxidant, antiaging, antiwrinkle and whitening.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.4
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• pp.259-268
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• 2008

In this study, the antioxidative effects, inhibitory effects on tyrosinase and elastase and components of Castanea crenata leaf were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl radical, DPPH) scavenging activity ($FSC_{50}$) of extract / fractions of Castanea crenata left was in the order: 50% ethanol extract ($13.6{\mu}g/mL$) < ethyl acetate fraction (6.2) < aglycone fraction (2.1). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$ of extract / fractions from Castanea crenata leaf extract / fractions on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity was in the order: aglycone fraction (0.8) < 50% ethanol extract (0.5) < ethyl acetate fraction (0.3). The scavenging activity ($IC_{50}$ for ${O_2}^{{\cdot}\;-}$ (superoxide anion radical) generated by NBT method was in the order: ethyl acetate fraction (145.5) < aglycone fraction (65.5). The protective effects on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction exhibited the most prominent cellular protective effect (${\tau}_{50}$, $191.9{\pm}12.2\;min$ at $10{\mu}g/mL$). The inhibitory effect of aglycone fraction ($9.1{\mu}g/mL$) on elastase was higher than oleanolic and ($13.7{\mu}g/mL$). And the inhibitory effect of aglycone fraction ($21.6{\mu}g/mL$) on tyrosinase was higher than arbutin ($226.2{\mu}g/mL$). But 50% ethanol extract rarely exhibited the inhibitory activity on tryosinase and elastase. Flavonoids were contained in Castanea crenata left (96.3 mg / 100 g dried Castanea crenata leaf). And flavonoids contained in ethyl acetate fraction were kaempferol, quercetin, quercitrin, and so on. Quercitrin is the most abundant component. These results indicate that extract / fractions of Castanea crenata can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging free radical and ROS, Castanea crenata leaf extract/ fractions could be used as new cosmeceutical for whitening and anti-wrinkle products.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.306-316
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• 2006

In this study, the effect of the shade level, water flow rate applied to the shades and the temperature of water on the greenhouse cooling was investigated depending on the shade level of 0, 35, 55, 75%, and water flow rate and water temperature by the test on the small wooden frames to find out the low cost cooling method. With increasing of the dry bulb temperature of outside air, the dry bulb temperature in the wooden frames increased. For the frames with the shade and water, inside temperatures of the frames were lower of -0.2$\sim$-1.2$^{\circ}C$ than the temperature of the outside air and higher than the water temperature. For the frames without water, inside temperatures of the frames were higher of 1.7$\sim$4$^{\circ}C$ than the outside and not affected by the shade level very much. The water flow rate and the temperature of the water were not the important factors to decrease the inside temperatures in the frames. The black globe temperature became lower with increasing of shade level. The shade frames with water curtain showed the best cooling effect because of reducing thermal radiation and cooling the plastic film cover. The surface temperatures of the plastic film cover for the water supplied modules became lower with increasing of the shade level. The relative humidity was decreased with the dry bulb temperature in the frame increasing and not affected by the dry bulb temperature of the outside air for the frames with the shade and water.

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.32-49
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• 1998

For estimation of regional myocardial blood flow with O-15 water PET, a few modifications considering partial volume effect based on single compartment model have been proposed. In this study, we attempted to quantify the degree of heterogeneity and to show the effect of tissue flow heterogeneity on partition coefficient(${\lambda}$) and to find the relation between perfusable tissue index(PTI) and ${\lambda}$ by computer simulation using two modified models. We simulated tissue curves for the regions with homogeneous and heterogeneous blood flow over a various flow range(0.2-4.0ml/g/min). Simulated heterogeneous tissue composed of 4 subregions of the same or different size of block which have different homogeneous flow and different degree of slope of distribution of blood flow. We measured the index representing heterogeneity of distribution of blood flow for each heterogeneous tissue by the constitution heterogeneity(CH). For model I, we assumed that tissue recovery coefficient ($F_{MME}$) was the product of partial volume effect($F_{MMF}$) and PTI. Using model I, PTI, flow, and $F_{MM}$ were estimated. For model II, we assumed that partition coefficient was another variable which could represent tissue characteristics of heterogeneity of flow distribution. Using model II, PTI, flow and ${\lambda}$ were estimated. For the simulated tissue with homogeneous flow, both models gave exactly the same estimates, of three parameters. For the simulated tissue with heterogeneous flow distribution, in model I, flow and $F_{MM}$ were correctly estimated as CH was increased moderately. In model II, flow and ${\lambda}$ were decreased curvi-linearly as CH was increased. The degree of underestimation of ${\lambda}$ obtained using model II, was correlated with CH. The degree of underestimation of flow was dependent on the degree of underestimation of ${\lambda}$. PTI was somewhat overestimated and did not change according to CH. We conclude that estimated ${\lambda}$ reflect the degree of tissue heterogeneity of flow distribution. We could use the degree of underestimation of ${\lambda}$ to find the characteristic heterogeneity of tissue flow and use ${\lambda}$ to recover the underestimated flow.