• Journal of fish pathology
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• v.4 no.2
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• pp.59-70
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• 1991

In order to investigate the effects of glutathione against ceroidosis on flounder, Paralichthys olivaceus, a serial experiment was carried out at indoor tanks in Cheju province, the southern island of R.O.Korea, from October 1 to November 4 of 1991. The choosed group of flounder for this experiment, ranged from 92 to 122g in body weight, already showed a distinct histological ceroidosis in liver, spleen, kidney about six months before this experiment. They were fed on formulated diets supplemented with glutathione of 0mg, 1mg, 2mg, 5mg, 10mg per kg of diet per day. Some flounders were fed on the decomposed diet as a control continuosuly. Two individuals fed on the experimental diets were cought at an interval 7 days for 35 days and analyzed the values of blood indexs. 1. While the values of RBC, Hb, Ht, MCHC, MCV of flounder fed on the decomposed diet and the glutathione non-supplemented diet were not changed compared with the beginning levels of experiment, those fed on the glutathione supplemented diets, showed markedly increased values from 7th day of experiment and from 21th day of experiment reached to the values of healthy flounder. 2. The variation of TP, Glu, Alp, BUN, TG, T-cho, GOT and GPT were not observed in the groups fed on the control diet and glutathione non-supplemented diet. In contrast, those values in the groups fed on the glutathione supplemented diets were markedly decreased from 7th day and become constant from 21th day. 3. The effect of glutathione supplementation with high concentration in diets showed much better improvements of symptoms concequently, compared with those of low concentration diets.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.20-26
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• 2018

This study was conducted to develop a device for measuring the air flow by space variation through monitoring program, which acquires data by each point from each environmental sensor located in the greenhouse. The distribution of environmental factors(air temperature, humidity, wind speed, etc.) in the greenhouse is arranged at 12 points according to the spatial variation and a large number of measurement points (36 points in total) on the X, Y and Z axes were selected. Considering data loss and various greenhouse conditions, a bit rate was at 125kbit/s at low speed, so that the number of sensors can be expanded to 90 within greenhouse with dimensions of 100m by 100m. Those system programmed using MATLAB and LabVIEW was conducted to measure distributions of the air flow along the greenhouse in real time. It was also visualized interpolated the spatial distribution in the greenhouse. In order to verify the accuracy of CFD modeling and to improve the accuracy, it will compare the environmental variation such as air temperature, humidity, wind speed and $CO_2$ concentration in the greenhouse.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.147-152
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• 2015

In order to develop the cooling load estimation method in the greenhouse, the cooling load calculation formula based on the heat balance method was constructed and verified by the actual cooling load measured in the fog cooling greenhouse. To examine the ventilation heat transfer in the cooling load calculation formula, we measured ventilation rates in the experimental greenhouse which a cooling system was not operated. The ventilation heat transfer by a heat balance method showed a relatively good agreement. Evaporation efficiencies of the two-fluid fogging system were a range of 0.3 to 0.94, average 0.67, and it showed that they increased as the ventilation rate increased. We measured thermal environments in a fog cooling greenhouse, and calculated cooling load by heat balance equation. Also we calculated evaporative cooling energy by measuring the sprayed amount in the fogging system. And by comparing those two results, we could verify that the calculated and the measured cooling load showed a relatively similar trend. When the cooling load was low, the measured value was slightly larger than calculated, when the cooling load was high, it has been found to be smaller than calculated. In designing the greenhouse cooling system, the capacity of cooling equipment is determined by the maximum cooling load. We have to consider the safety factor when installed capacity is estimated, so a cooling load calculation method presented in this study could be applied to the greenhouse environmental design.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.275-283
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• 2013

The patient radiation dose is different depending on selection of Ion chamber when taking Chest PA which using AEC. In this paper, we studied acquiring the best diagnostic images according to selection of Ion chamber on AEC mode as well as minimizing patient radiation dose. Experimental methods were selection of Ion chamber and change of sensitivity under the same conditions as Chest PA projection. At AEC mode, two upper ion chambers sensors and one lower ion chamber sensor were divided into 7 cases according to selection of on/off. after measuring five times respectively, we obtained average value and calculated exposure dose. Image assessment was done with measured Modulation Transfer Function, Peak Signal to Noise Ratio, Root Mean Square, Signal to Noise Ratio, Contrast to Noise Ratio, Mean to Standard deviation Ratio respectively. In exposure assessment results, selection of two upper chambers was the lowest. In resolution assessment results, image of two upper chambers had the second high spatial frequency at sensitivity at 625(High) was 1.343 lp/mm. RMS value of image selecting two upper chambers was low secondly. SNR, CNR, MSR were the high value secondly. As the sensitivity was increased, radiation dose was decreased but better image could be obtained on image quality. In order to obtain the best medical images while minimizing the dose, usage of two upper ion chambers is considered to be clinically useful at sensitivity 625(High).

• Journal of Astronomy and Space Sciences
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• v.26 no.3
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• pp.403-416
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• 2009

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and developed by KARl for communication, ocean and meteorological observations. It will be tested under vacuum and very low temperature conditions in order to verify thermal design of COMS. The test will be performed by using KARI large thermal vacuum chamber, which was developed by KARI, and the COMS will be the first flight satellite tested in this chamber. The purposes of thermal balance test are to correlate analytical model used for design evaluation and predicting temperatures, and to verify and adjust thermal control concept. KARI has plan to use heating plates to simulate space hot condition especially for radiator panels of satellite such as north and south panels. They will be controlled from 90 K to 273 K by circulating GN2 and LN2 alternatively according to the test phases, while the main shroud of the vacuum chamber will be under constant temperature, 90 K, during all thermal balance test. This paper presents thermal modelling including test chamber, heating plates and the satellite without solar array wing and Ka-band reflectors and discusses temperature prediction during thermal balance test.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.29-36
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• 2018

Ulmus davidiana supercritical fluid residue EtOH extracts(USCFR) and ethyl acetate solvent fraction (USCFREA) of supercritical extraction foil were investigated in order to examine the recycling of supercritical extraction foil in the process of studying Ulmus davidiana branch supercritical extract. Experiments were performed for the determination of total phenol content. The $IC_{50}$ value(ppm) of DPPH radical scavenging activity and ABTS radical scavenging activity was $7.42{\pm}0.09$, $7.50{\pm}0.05$, $22.94{\pm}0.09$, $6.43{\pm}0.10$, and USCFREA, respectively, as compared with the positive control (vitamin C) with values $17.80{\pm}0.14$ and $5.34{\pm}0.06$, respectively. The antioxidative activities of USCFR and USCFREA were confirmed to be superior to the positive control group. In anti-allergic activity studies, both USCFR and USCFREA showed concentration-dependentanti-allergic activity, and USCFREA showed strong anti-allergic activity even at very low concentrations. Thetotal phenolic contents (ugEG, ugGA; ppm) of USCFR were $134.17{\pm}0.13$, $132.02{\pm}0.24$ and USCFREA were $154.77{\pm}1.05$ and $153.18{\pm}1.10$, respectively. Based on the above results and strong antioxidant activity, USCFR and USCFREA hold the potential to be considered as basic research materials for the development of therapeutic supplements based medicines or functional cosmetics related to chronic inflammatory skin immunity diseases.

• Conservation Science in Museum
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• v.2
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• pp.77-82
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• 2000

The purpose of this study is to evaluate the effect of ART-SORB which is commonly used in museums and galleries at home and abroad including National Museum of Korea, so as to collect useful information to control micro-environment. Experiment was conducted in air-tight condition in order to evaluate only the effect of ART-SORB excluding any influence from outside factors. A certain amount of ART-SORB considering the case size and ART-SORB in cassette type were used to evaluate the humidity controlling capability. The result showed that target humidity was reached in 10~17 hours in case of using corresponding amount of ART-SORB to the cubic volume and in 5~6 hours in case of excessive use of cassette type ART-SORB. And it also showed that humidity can be controlled in the range of RH 50~70%. In addition, ART-SORB was excellent at raising humidity at low humidity and poor at high humidity. Therefore, ART-SORB turned out to be an effective humidity buffer for controlling micro-environment of such artifacts as wooden ware, lacquer ware and paintings, which require high humidity. However, unfortunately, there are some difficulties in applying this result to real condition, given the fact that this study was conducted under firm air-tight case. Therefore, ART-SORB can be fully effective only in firm air-tight case.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.105-111
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• 2017

Hyaluronic acid (HA) has been investigated for biomedical and pharmaceutical applications. This study was conducted to determine the distributions of HA nanoparticles (NPs; size 350-400 nm) and larger HA polymers in mice at intervals after application. $^{177}Lutetium$ (Lu)-labeled HA-NPs or HA polymers were intravenously injected (5 mg/kg) into male ICR mice, and radioactivity levels in blood and target organs were measured from 0.25 h to 28 days post-injection. In blood, the radioactivities of HA-NPs and HA polymer peaked at 0.5 h after injection but were remarkably decreased at 2 h; subsequently, they maintained a constant level until 6 days post-injection. HA-NPs and HA polymers were observed in the liver, spleen, lung, kidney, and heart (in ascending order) but were seldom observed in other organs. After 3 days, both the HA-NP and HA polymer levels showed similar steady decreases in lung, kidney, and heart. However, in liver and spleen, the HA-NP levels tended to decrease gradually after 1 day and both were very low after 14 days, whereas the HA polymer level accumulated for 28 days. The results indicate that HA-NPs, with their faster clearance pattern, may act as a better drug delivery system than HA polymers, especially in the liver and spleen.

• Journal of Technologic Dentistry
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• v.31 no.3
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• pp.67-85
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• 2009

This study aims to provide the research for dental technician's stress prevention and management with basic materials by understanding dental technician's psychosocial stress level and examining relevant factors. The subject of this study is 255 dental technologists who work mainly in Seoul Gyeonggi district for a month of April of 2009 and I conducted cross-sectional study through self administered survey. The contents of survey include general feature, occupational feature, health behavior feature. I used Karasek's Job Content Questionnaire, JCQ and Psychosocial well-being index, PWI-SF as means of measurement. To compare the level of dental technician's psychosocial stress, I conducted t-test and ANOVA and I measured the factors that are related with psychosocial stress symptom with step by step multiple regressive analysis. According to the result of Cronbach's a value which is yielded to verify the reliability of means of measurement, the reliability of concept is sufficient. The detailed result of this study is as follows. 1. According to the result of analyzing the stress symptom in accordance with general feature and occupational feature, those dental technologists who are older and not married, graduate from junior college, have lower position, work at university hospital or general hospital show lower stress(p<0.05). There is no difference in the level of psychosocial stress with regard to duty related feature, period of service, daily average working hours, monthly average pay. 2. With regard to health behavior feature, those dental technologists who control weight better and have meal more regularly show lower stress(p<0.05). Those dental technicians who smoke, drink liquid and take a suitable sleep show low stress but the difference does not have significance statistically. 3. With regard to the factors of stress in the workplace, those dental technicians who have lower duty related requirement, have higher duty related control ability, have higher social support, have less instability of employment and have less workload and physical burden show lower stress(p<0.05). 4. According to the result of analyzing the factors that influence dental technologist's stress symptom, social support has the most enormous influence on stress symptom. Unstable employment, regular exercise, regular eating, daily average sleeping hours and technological capacity are also important in this order. According to the result of this study, those dental technicians who have higher social support, less instability of employment, do exercise more regularly, take enough sleep more soundly and have higher technological capacity show lower psychosocial stress symptom. Therefore, to adjust appropriately the dental technician's stress and properly maintain and improve the dental technician's mental health, effective management plan that enables dental technicians to maintain smooth human relationships for dental technicians should be sought. In addition, heath education and health management for dental technicians should be given more thoroughly so that they can establish desirable health behavior in daily life.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.415-419
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• 2007

This study was conducted to compare the storability of some sprout vegetables; alfalfa, broccoli, radish, red-cabbage, and red-radish, packed with 50 low density polyethylene (LDPE) film in MA storage. Most of all 5 different sprout vegetable crops maintained the fresh weight higher than 99% until 10 days storage at 2 and $8^{\circ}C$. The carbon dioxide concentration in packages was higher at 8 than at $2^{\circ}C$. It was higher in radish and red-radish sprouts than other crops. As the oxygen concentration showed opposite trends to carbon dioxide, that of radish and red-radish sprouts decreased more than 3% after 3 days in 8 storage. Ethylene concentration in the packages of alfalfa was 0.1 ppm, significantly higher than other four crops with less than 1.0 ppm. Temperature treatment, however, did not influence the ethylene concentration in packages. The radish and red-radish sprouts, with lowest oxygen concentration in package, showed lowest off-flavor compared to the others. The visual quality of these sprouts in packages showed higher at $2^{\circ}C\;than\;at\;8^{\circ}C$ and was maintained the highest in radish sprouts, followed by red-radish, broccoli, red-cabbage, and alfalfa sprouts in that order. In conclusion, as the sprout vegetables have different shelf-life, of which radish was $4{\sim}5$ days longer than that of alfalfa the distributed condition of sprout vegetables should be differently controlled according to kinds of crops.