• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.505-510
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• 2012

The gas hold-up has a strong relationship with the size distribution and rising velocities of bubbles in a bubble column. Therefore, many previous researchers have studied on the hydrodynamics focusing on the bubble size variation in bubble column. In this study, the bubble behavior was influenced by partitioning porous plates installed at a certain height in a trayed bubble column. The gas hold-up was increased in non-sparging region (H/D > 5) as well as sparging region. We identified the effect of the partitioning porous plate using three trayed bubble columns with different reactor geometries. Furthermore, the bubble break-up frequency and size distribution were observed before and after individual bubbles penetrated through the plate. The arrangement of the plates was also investigated using a 0.15-m-in-diameter bubble column. Based on the result, we applied this design concept to a 0.36-m-in-diameter, 22 m tall trayed bubble column and identified the effect of the partitioning porous plate on the gas hold-up increase.

• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.510-515
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• 2011

This study was performed to quantitatively assess the normal lung volume and density according to the position by multi-detector computed tomography (MDCT) in dogs. Helical CT of the thorax was performed on 4 different positions with dorsal, left lateral, right lateral and ventral recumbency in 6 Pekingese and 6 Maltese dogs. During CT scanning, dogs were kept hyperventilated. Through the 3-dimensional reconstruction of CT images, the lung parameters were measured as the volume and density of the left, right including accessory lobe, and total lung. 3D images represented the different lung shape between Pekingese and Maltese dogs. Their difference of total lung volume and total lung density was not significant on the each position in both breeds. Right lung volume was significantly higher than left. The difference of left and right volume was $66.91{\pm}25.1$ ml. Linear relationship was shown between body weight and lung volume of ventral recumbency position. The dependent lung had higher density and lower volume than nondependent lung in both breed dogs. The volume of nondependent lung was not changed compared with the volume on ventral or dorsal recumbency. The total lung volume measured with MDCT is correlated with the lung density, and the lung density is useful to predict the normal total lung volume.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.1
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• pp.51-59
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• 2013

This study was conducted to compare the sizes of effective values, which users recognize, according to the kinds of physical and psychological services provided by an arboretum, by estimating them in monetary values. As an analysis tool for this purpose, the CE(Choice Experiments) method, which is able to estimate effective value's size depending on each variable, was employed. For drawing up profiles for estimation of the values of individual services, 25 profiles were extracted using the orthogonal design of the SPSS statistical package, and questions of 75 pairs were created not to make each of the profiles overlapped. Then, each user was given three questions at five sets each and 3,510 data were used for the analysis. As the result, in relation to the attribute, 'The kinds of trees should be diversified 50% more than now.', firstly, users showed the biggest willingness to pay, based on the present level, and expressed intentions to pay 7,956 won, additionally. Secondly, the value of the path design that was unique than the present road design was estimated in 6,025 won, and when individual attendants guided visitors in the arboretum, they expressed intentions to pay nearly three times more expenses than when they were guided as a group. These results show that users in the Gyeongnam Arboretum recognized the highest effective values towards the collection and display of trees that are arboretum's original functions, and it was followed by the unique road design to observe a variety of dense trees well. This research could be useful in comparing or measuring particular effective values of users that central operators of arboretums want to know. Moreover, it would be suggested as an advanced research for providing basic data about value estimation of individual environmental goods not only in arboretums, but also in other fields.

• Fisheries and Aquatic Sciences
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• v.4 no.2
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• pp.75-83
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• 2001

This study is to investigate biochemical compositions of two species of marine microalgae, Chlorella ellipsoidea of Chlorophyta and Tetraselmis suecica of Prasinophyta, and to assess their potential antimicrobial activities. Crude protein, lipid and carbohydrate for C. ellipsoidea were $43.15\%$, $12.63\%$ and $13.09\%$, respectively, and those for T. suecica were $44.95\%$, $4.80\%$ and $24.05\%$, respectively. The major amino acids of the two micro algae were aspartic acid, glutamic acid, glycine, alanine, valine, leucine, lysine and proline, and no significant difference between the amino acid compositions of both micro algae was observed. The major sugars for both microalgae were glucose, galactose and mannose, and glucose contents showed the highest level, $58.70\%$ for C. ellipsoidea and$57.86\%$ for T. suecica. The major mineral contents of both micro algae for 100g were Ca (3,114mg in C. ellipoidea and 3,389mg in T. suecica) and followed by Na (2,881mg), K (548mg) and Mg (545mg) for C. ellipsoidea and Na (1,832 mg), Mg (1,510mg) and K (548mg) for T. suecica. In the content of ATP-related compound, hypoxanthine in C. ellipsoidea and IMP in T. suecica were absolutely dominant compounds. The highest content of fatty acid in C. ellipsoidea was 20:4, $27.15\%$ and that in T. suecica was 18:3 (w-6), $18.10\%$. In case of physiologically important polyunsaturated fatty acids like eicosapentaenoic acid (20: 5) and docosahexaenoic acid (22: 6), both microalgae possessed just trace amounts but was rich in arachidonic acid (20: 4). Vitamin content in both microalgae was significantly high in choline and inositol. In antimicrobial activity by water- and fat-soluble fraction of the micro algae, hexane extract in the fat-soluble fraction of C. elliposidea inhibited the growth of Bacillus subtilis by $96\%$ bactericidal activity and tetrachlorocarbon extract of T. suecica indicated relatively excellent antimicrobial activity $(81\%\;bactericidal\;activity)$ against Escherichia coli. Hot water extract among water-soluble fraction of both micro algae almost suppressed the growth of Staphylococcus aureus by $96\%$ bactericidal activity.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.4
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• pp.503-510
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• 2015

The objective of this study is to analyze the investment adequacy of the projects implemented according to the master plan on sewerage rehabilitation at Seoul. The planned and actually implemented ratio of invested money on sewage treatment plants (STPs) to sewers were compared in two temporal periods. Though the planned ratio of investment on STPs to sewers was 50:50 (in 2009-2020), the actual implemented ratio in 2009-2013 was 34:66. Until 2020, the greater investment ratio on STPs to sewers should be made considering the necessity of coping with stricter legal compliance on advanced treatment, stormwater treatment and so on. The priority of the planned and partially implemented projects among four STPs and at each STP was evaluated. Considering only the performance indicator of reduced load of BOD, T-N, T-P per the capacity of each STP facility, the performance among four STPs was shown as Jung-Rang>Tan-Cheon>Seo-Nam>Nan-Ji. The reverse order of the performance results in the past may be considered for future investment priority, but the efficiency of operation implemented at each STP, deteriorated status of each STP, investment in the past and so forth should also be considered. As for the priority of projects conducted within each STP, projects related to legal compliance (such as advanced tertiary treatment, stormwater treatment, etc.) have highest priority. Odor-related project and inhabitant-friendly facility related projects (such as building park on STPs, etc.) has lower priority than water quality related projects but interactivity with end-users of sewerage should also be important.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.495-510
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• 2017

This study was to investigate the antioxidant activities of Cryptomeria japonica leaves extracts such as essential oil, methanol extract and hot water extract and to evaluate its potential as a natural antioxidant. Antioxidant activities of extracts were evaluated by DPPH radical scavenging activity, FRAP activity, zanthin oxidase inhibitory activity, and iron ion chelate activity, comparing with the positive controls. According to the results, methanol and hot water extracts showed higher antioxidant activities than essential oil. This fact suggested that terpenoids have lower antioxidant effect than phenolic compounds which were found in methanol and hot water extracts. Especially, acetone and water soluble fractions of methanol extract and ethanol fraction of hot water extract contained a lot of phenolic compounds and hydroxyl group, indicating that many hydroxyl groups and glycosidic bonds showed higher antioxidant effect than the other fractions. These results can suggest that the phenolic compounds which contained hydroxyl group or glycosidic bonds have a certain role for effective antioxidant activities.

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.499-510
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• 2009

In this paper, relative orbit of Low Earth Orbit satellites is determined using only GPS measurements and the effects of Equatorial Spread-F (ESF), that is one of biggest ionospheric irregularities, are investigated. First, relative orbit determiation process is constructed based on doubly differenced GPS observations. In order to see orbit determination performance, relative orbit of two GRACE satellites is estimated for one month in 2004 when no ESF is observed. The root mean square of the achieved baselines compared with that from K-Band Ranger sensor is about 2~3 mm and average of 95% of ambiguities are resolved. Based on this performance, the relative orbit is estimated for two weeks of two difference years, 2003 when there are lots of ESF occurred, and 2004 when only few ESF occurred. For 2003, the averaged baseline error over two weeks is about 15 mm. That is about 4 times larger than the case of 2004 (3.6 mm). Ionospheric status achieved from K-Band Ranging sensor also shows that more Equatorial Spread-F occurred at 2003 than 2004. Investigation on raw observations and screening process revealed that the ionospheric irregualarities caused by Equatorial Spread-F gave significant effects on GPS signal like signal loss or enhancement ionospheric error, From this study, relative orbit determination using GPS observations should consider the effect of Equatorial Spread-F and adjust orbit determination strategy, especially at the time of solar maximum.

• Korean Journal of Clinical Pharmacy
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• v.26 no.4
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• pp.306-311
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• 2016

Objective: This study was performed to compare the changes in the blood concentrations of tacrolimus when either itraconazole or voriconazole is together with tacrolimus to prevent or treat invasive aspergillus pneumonia (IAP) in patients with lung transplants. Therefore we can compare the degree of drug-drug interactions between tacrolimus and itraconazole against tacrolimus and voriconazole. Methods: Patients who were admitted and had lung transplants in a territory referral hospital from September 2012 to May 2015 were analyzed retrospectively. The effects of itraconazole and voriconazole on the plasma concentrations of tacrolimus were analyzed. Results: Mean tacrolimus concentrations was $10.49{\pm}2.35ng/mL$ vs. $10.95{\pm}2.98ng/mL$ (p=0.722), and mean concentration of tacrolimus over the dose of tacrolimus per day was $8.510{\pm}5.890(ng/mL)/(mg/d)$ vs. $15.45{\pm}28.47(ng/mL)/(mg/d)$ (p=0.947) in itraconazole vs. voriconazole group each. The ratio of the number of the results out of target tacrolimus concentrations to the total number of tacrolimus concentration results was $18.0{\pm}13.3%$ vs. $24.4{\pm}18.5%$ (p=0.185). Conclusion: There were no significant differences between itraconzaole and voriconazole to have influences on mean concentrations of tacrolimus over tacrolimus dose per weight per day. However voriconazole tended to raise tacrolimus plasma concentrations more than itraconazole. Safer and more effective drug management to prevent and treat fungal infections should be done by therapeutic drug monitoring not only of tacrolimus but of itraconazole and voriconazole in lung transplant patients.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.229-236
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• 2018

Pesticides are widely sprayed by the growers in street trees and planting areas which include urban forests, community forests and city parks to control pests. Spraying pesticides not only affect the people who sprayed but also affect the unspecified citizens who's are exposed to pesticides sprayed trees by contact or inhalation. A few studies have been conducted to measure the amount of pesticides in forest area but no studies have been conducted to measure the pesticide amount in tree in public living space. So, in our study, we investigated the amount of pesticides in cotton gloves, in leaf residue, and respiratory exposure for a certain period of time after applying Fenitrothion EC to Korean boxweed tree (Buxus Koreana) to know the safety time of pesticides after spraying. We found that, up to 4d, there was no significant difference of the amount of Fenitrothion on leaves. But the amount of pesticides on gloves was significantly higher on 1h ($510.1{\mu}g$) and 24h ($405.4{\mu}g$) than 48h ($45.0{\mu}g$) after spraying. The amount of pesticides on inhalation was also significantly higher in 1 h ($0.2{\mu}g$) and 24 h ($0.1{\mu}g$) than 48 h after spraying. After 48h, we did not find pesticides amount in inhalation. Thus, we was considered necessary to pay attention to 48h after spraying of pesticide Fenitrothion.

• The Korean Journal of Food And Nutrition
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• v.31 no.4
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• pp.502-510
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• 2018

To begin with, this study identified and reviewed the proximate compositions, quality and physicochemical characteristics of three Korean cowpea (Vigna unguiculata L. Walp.) cultivars grown in two different seedling periods. The proximate compositions of the cowpea showed significant differences according to three cultivars (Seowon, Yeonboon and Okdang) and two different seeding periods (5 June and 5 July). Through this lens, the lightness, redness and yellowness of the cowpea cultivars increased slightly during the 5 July cultivation compared to the 5 June cultivation. This brings us to understand that the water binding capacity, water solubility index, and swelling power were significantly different among the cultivars. In this case, the water binding capacity of the cowpea was 108.87~143.19%, and decreased during the 5 July cultivation compared to the 5 June cultivation. As shown, the total polyphenol and flavonoid contents of cowpea showed significant difference according to cultivars. In this case, the total polyphenol content of 5 June and 5 July cultivation on the Seowon 4.17 and 4.12 mg GAE/g, respectively. In these terms, the DPPH radical scavenging activity of cowpea showed a significant difference according to the cultivars, and the Yeonboon and Okdang increased slightly during 5 July cultivation. The ABTS radical scavenging activity of the cowpea showed significant difference according to the cultivars, and all cultivars decreased slightly during the 5 July cultivation. In other words, the phenol contents and radical scavenging activity differ measurable depending on the cultivars and seeding periods. Therefore, it is necessary to study the proper cultivar and seeding time considering the environment of the applicable cultivation area.