• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.344-353
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• 2020

Plants native in Korea have not only ornamental values but also have excellent environmental adaptability, so they can be used as garden plants. Studies on proper volumetric water content (VWC) of substrates have been reported, but many have been conducted in glasshouse conditions where environmental factors were controlled. When considering garden planting, it is necessary to perform the automated irrigation system in outdoor conditions where rainfall occurs at frequent intervals. This research aimed to investigate the VWC suitable for the growth of Minuartia laricina, Arenaria juncea, and Corydalis speciosa in open filed. Sandy soil which consisted of particles of weathered rock was used, and the VWC of 0.15, 0.20, 0.25, and 0.30 ㎥·m^-3 was maintained using an automated irrigation system with capacitance soil moisture sensors and a data logger. No significant differences in growth and antioxidant enzymes activity of A. juncea were observed among VWC treatments. However, the survival rate was low at VWC 0.30 ㎥·m^-3 treatment, which was the highest soil moisture content. Even considering the efficiency of water use, we recommended that VWC 0.15-0.20 ㎥·m^-3 is suitable for the cultivation of A. juncea. Minuartia laricina showed better growth with lower VWC. Because of frequent rainfall in open field, plant volume and survival rate was high even in VWC 0.15 ㎥·m^-3 treatment. In C. speciosa, the plant height, number of shoots and lateral shoots, and fresh and dry weight were higher in plants grown in VWC 0.25 ㎥·m^-3 as compared with that in the plants grown at 0.15, 0.20, and 0.30 ㎥·m^-3. Based on these results, M. laricina needed less water in open filed, and A. juncea and C. speciosa required higher VWC, but excessive water should be avoided.

• Journal of the Mineralogical Society of Korea
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• v.28 no.3
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• pp.245-253
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• 2015

The performance of $TiO_2$ photo-catalytic oxidation process is significantly dependent on the amount of hydroxyl radicals produced during the process, and it is an essential prerequisite to quantify its production. However, precise and accurate methods for quantification of hydroxyl radicals have not been developed so far. For this reason, this study was initiated to compare existing methods for analysis of hydroxyl radicals produced by $TiO_2$ photo-catalytic oxidation and to propose a new method to overcome the limitation of established methods. To simulate $TiO_2$ photo-catalytic oxidation process, Degussa P25 which has been widely used as a standard $TiO_2$ photo-catalyst was used with the dose of 0.05 g/L. The light source of process was UVC mercury low-pressure lamp (11 W, $2,975mW/cm^2$). The results indicate that both potassium iodide (KI)/UV-vis spectrometer and terephthalic acid (TPA)/fluorescence spectrometer methods could be applied to qualitatively measure hydroxyl radicals via detection of triiodide ion ($I_3{^-}$) and 2-hydroxyterephthalic acid which are produced by reactions of iodine ion ($I^-$) and TPA with hydroxyl radicals, respectively. However, it was possible to quantitatively measure hydroxyl radicals using TPA method coupled with high-performance liquid chromatograph (HPLC). The analytical results using TPA/HPLC method show that hydroxyl radical of 0.013 M was produced after 8 hours operation of photo-catalytic oxidation under specific experimental conditions of this study. The proposed method is expected to contribute to precise the evaluation of the performance of photo-catalytic oxidation process.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.213-220
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• 2014

This is the study to conduct the topographical analysis using the orthophotographic data from the waypoint flight using the UAV and constructed the system required for the automatic waypoint flight using the multicopter.. The results of the waypoint photographing are as follows. First, result of the waypoint flight over the area of 9.3ha, take time photogrammetry took 40 minutes in total. The multicopter have maintained the certain flight altitude and a constant speed that the accurate photographing was conducted over the waypoint determined by the ground station. Then, the effect of the photogrammetry was checked. Second, attached a digital camera to the multicopter which is lightweight and low in cost compared to the general photogrammetric unmanned airplane and then used it to check its mobility and economy. In addition, the matching of the photo data, and production of DEM and DXF files made it possible to analyze the topography. Third, produced the high resolution orthophoto(2cm) for the inside of the river and found out that the analysis is possible for the changes in vegetation and topography around the river. Fourth, It would be used for the more in-depth research on landscape analysis such as terrain analysis and visibility analysis. This method may be widely used to analyze the various terrains in cities and rivers. It can also be used for the landscape control such as cultural remains and tourist sites as well as the control of the cultural and historical resources such as the visibility analysis for the construction of DSM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1314-1319
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• 2005

The purpose of this study was to investigate the antioxidative effects of Lycii fructus powder (LFP) solvent extracts and Maejakgwa made with LFP. The solvent extracts of LFP were added to soybean oil in the quantity of $0.05\%$. The solvents used were methanol, ethanol, ethyl acetate and petroleum ether. Soybean oil without the addition of LFP was used as a negative control. Soybean oil with $0.02\%$ butylated hydroxytolune (BHT) and $\alpha$-tocopherol were used as positive controls. Each sample was stored at $50^{\circ}C$ for 30 days. The oxidation level of these samples was determined by measuring the acid value, peroxide value and thiobarbituric acid (TBA) value. The oxidation level of solvent extracts of $0.05\%$ LFP was lower than both the negative control and $\alpha$-tocopherol. Especially, methanol extract of $0.05\%$ LFP was the lowest. The methanol extract (320 min) and ethanol extract (316 min) demonstrated longer induction periods, compared to the control (253 min), $\alpha$- tocopherol (255 min) and BHT (309 min) by Rancimat method. Acid value of Maejakgwa was increased during the storage time, but it was lower in Maejakgwa made with LFP than in the control group. Peroxide value was increased rapidly for 30 days and then decreased. TBA value was lower in Maejakgwa made with 3, 6, $9\%$ LFP than in those made with $15\%$ LFP and the control.

• Journal of Korean Society of Forest Science
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• v.55 no.1
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• pp.68-75
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• 1982

This study was carried out to promote percent survival of the walnut seedling grafting. The hardwood scions of the walnut were grafted on the nures seed-stock of the Juglans mandshurica Mat in an electric heating bed, then planted in field. The results obtained from the study were as follows : The optimum time of scion cpllection was from January to February. The best medium of the seed bed was sandy soil. The best grafting time was form the early to the 20the of the march. When the grafted seedling in the heating bed was trans-planted on filed 90percent of the seedlings was survived until autmn. The percent grafting on the elective heating bed was 90%. Crown gall occuring frequently in chestnut nurse graft was not appeared in juglans mandshurica Max grafted seedling of after outplanting. The grafted seedlings have not shown any physiological defects but developed normaly 3 years since grafting.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.219-226
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• 1986

To confirm the application of a newer in vitro assays to determining the nutritional value of marine crustaceans (mainly shrimps and crabs), which have been considered to be highly nutritive depending on their levels of the essential amino acids and digestibility, their C-PERs and DC-PERs were determined and studied the factors influencing their in vitro results. Four species of seawater shrimps and 2 species of seawater crabs were used in this experiment. The in vitro digestibilities showed $83{\sim}86\%$ for raw shrimps and the trypsin indigestibile substrate content (TIS) was ranged from 1.32 to 3.33 mg/g solid expressed quantitatively as mg of purified soybean trypsin inhibitor. The smaller size of shrimps revealed a greater in vitro digestibility and a lower contents of TIS. It was noted that the in vitro digestibility of raw blue crab meat was around $85\%$ while boiled tenner crab meat showed $86\%$ or above, and the leg meat had the greatest in vitro digestibility in the various parts of crab meats. The poor in vitro digestibilities for shrimp's and crab's meat, compared with that of the other seafoods as noted in previous reports, suggest that the drop in pH, due to the change in their freshness during harvesting and frozen storage, resulted in underestimating their digestibilities using four-enzyme digestion technique. The lysine contents in all samples were higher than that of ANRC casein but they contained a slightly lower sulfur-containing amino acids than those in ANRC casein. But the other EAA, such as valine, tyrosine and phenylalanine, were found to be a half as little as that in casein and played a key-factor in calculation of C-PER or DC-PER. It was observed that the value of C-PER and DC-PER for all samples ranged from 2.1 to 2.4, and the predicted digestibilities showed $90\%$ or above in all samples. It was a different results from the fact that the animal proteins bear a higher values and predicted digestibilities than those of C-PER values. The lack of correlation between C-PER and DC-PER values is attributable to the fact that the lower content of valine, tyrosine and phenylalanine, and drop in pH owing to the changes of freshness in marine crustacea proteins. Therefore, if a newer in vitro digestion technique-which are taken into account the pH drop before digestion, TIS content and released free amino acids and/or peptides-developed, C-PER assays can provide more advantages in assessing the protein nutritional value of marine crustacea than any other in vitro assays.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.12
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• pp.1287-1293
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• 2008

In this study, a blend of 2-amino-2-methyl-1-propanol (AMP) and ammonia (NH$_3$) was used to achieve high absorption rates for carbon dioxide (CO$_2$) as suggested at several literatures. The absorption rates of aqueous AMP and blended AMP+NH$_3$ solutions with CO$_2$ and nitrogen dioxide (NO$_2$) were measured using a stirred-cell reactor at 303 K. The effect of the added NH$_3$ to enhance absorption characteristics of AMP was studied. The performances were evaluated under various operating conditions. The absorption rates increased following the increase of the concentration of NH$_3$. The absorption rate of NH$_3$ blended into 30 wt.% AMP solution with NO$_2$ at 303 K was 12.6$\sim$32.6% higher than that of aqueous AMP solution without NH3. Also, the addition of 3 wt.% NH$_3$ to 30 wt.% AMP increased 48.2$\sim$41.6% values for the reactions with CO$_2$ and NO$_2$ at 303 K. Therefore, it clearly shows that the reaction rate of AMP with CO$_2$ and NO$_2$ can be increased by the addition of NH$_3$.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.583-592
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• 2005

This experiment was conducted to determine the effects of dietary copper levels on performance, carcass characteristics, and economical analysis in Hanwoo steers. Fifteen Hanwoo steers weighing about 300kg were randomly allotted into one of three treatments. The three treatments consisted of Control(7mg Cu/kg feed), TI(12mg Cu/kg feed) and TII(17mg Cu/kg feed). Copper was formulated with concentrate from copper sulfate($CuSO_4$) and animals were fed the diets supplemented with copper from 300kg untill about 630 kg of body weight. Dietary copper levels did not affect daily weight gain, feed intake and feed efficiency during the whole feeding period. Dressing percentage, rib eye area and backfat thickness were not different between animals fed the diets supplemented with copper. Animals fed the diets supplemented with copper received the same B grade in yield grade. Animals fed the diets supplemented with copper received same marbling score. Beef color, fat color, texture and maturity were not affected by Cu supplementation in diet. Animals received the same first grade between treatments in quality grade. Animals fed the diet supplemented with 12mg of copper per kg diet was higher in profit by 13.3% than animals fed the control diet. According to these results, it may be concluded that performance, yield and quality grade were not affected by the Cu levels of 7 to 17mg per kg feed but crude income was enhanced when Hanwoo steers were fed the diet containing 12mg Cu/kg feed.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.388-395
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• 1987

In order to obtain a regulatory mutant strain with high cellulase activity, a newly isolated Penicillium verrculosum, strain F-3 was used as parental strain since it was proved to be an efficient cellulase producer. A number of experiments were conducted to determine the optimum conditions to in-duce mutagenesis and isolate the desirable mutant strains. Out of several restriction compounds tested, 1.5% oxgall was found to be most effective to restrict the colony size by suppressing overgrowth. Derepression of catabolites was employed as a criterion in selecting mutant strains with high cellulase productivity. Production of cellulase by Penicillium venculosum F-3 was suppressed when cultured on the media with more than 1% of glucose or glycerol. It was found that either irradiation with UV light for 19 mins or treatment with nitrosoguanidine at 200$\mu\textrm{g}$/m1 for 60 mins, induced mutagenesis at desired level, when the survival rate of the spore was 0.2% and 48%, respectively. Three mutant strains of F-3, UV-9, UV-10, and NTG-3 that had the highest cellulase productivity were finally selected, based on filter paper degradation rate, size of clearing zone on the screening plate and cellulase activity in the medium containing cellulose powder. When the mutant strains were compared with parental strain F-3, on the KC-M-W medium containing cellulose powder, the filter paper activities of UV-9, UV-10, and NTG-3 were increased by 34%, 55%, and 41%, respectively. However, the assimilation of cellobiose octaacetate by UV-9 or NTG-3 was markedly reduced. When the mutant UV-10 was grown on cellobiose octaacetate medium (CCA-4) in shaking flasks, the cellulase activities of the mutant increased by 20 to 50% compared to the parental strain. Excreation of soluble protein from the mutant also elevated up to 30%. The mutant also constitutively produced both CMCase and $\beta$-glucosidase, though at relatively low level, in the presence of glucose or cellobiose as carbon sources.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.195-202
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• 2005

Two experiments were conducted to evaluate the effects of dietary salt levels on the performance in laying hens and broilers. In experiment 1, 108 Avian broilers of 21 days age were conducted to evaluate broiler's performance. The broilers were divided into 6 treatment groups with 6 pens (3 broilers/pen), and 134 diets with different levels of salt with 0.25 (control), 0.5, 1.0, 1.5, 2.0 and $2.5\%$, respectively, for 3 weeks $(3\~5 weeks)$. The feed intake was not affected by the treatments. However, moisture content in feces was increased as increasing levels of dietary salt (P<0.05). In experiment 2, 135 ISA Brown laying hens were used to evaluate on performance of laying hens. The dietary supplementation of salt levels were prepared at 0.25 (control), 1, 2, 3 and $4\%$, respectively, for 4 weeks. Feed intake was decreased as increasing the dietary salt levels during the experiment (P<0.05). Particularly, it was lower in $3\%\;and\;4\%$ salt level treatments compared with the control (P<0.05). As expected, water intake was increased as increasing the dietary salt levels (P<0.05). Therefore, the present results could indicate that dietary salt content need to be considered for broilers and laying hens.