• Magazine of the Korean Society of Agricultural Engineers
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• v.29 no.3
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• pp.125-137
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• 1987

The purpose of this paper is to examine some difficulties in water management of agricultural reservoirs in Korea, for there are approximately more than 15,000 reservoirs which are now being utilized for the purpose of irrigation, along with the much amount of expenses and labors to be invested against droughts and floods periodically occurred. Recently, the effective use of water resources in the agricultural reservoirs with a single purpose, is becomming multiple according to the alterable environment of water use. Therefore, the task to allocate agricultural water rationally and economically must be solved for the multiple use of agricultural reservoirs. On the basis of the above statement, this study aims at suggesting the rational method of water management by introducing an optimal technique to allocate the water in an existing agricultural reservoir rationally, for the sake of maximizing the economic effect. To achieve this objective, a reservoir, called "0-Bongje" as a sample of the case study, is selected for an agricultural water development proiect of medium scale. As a model for the optimum allocation of water in the multi-purpose use of reservoirs a linear programming model is developed and analyzed. As a result, findings of the study are as follows : First, a linear programing model is developed for the optimum allocation of water in the multi-purpose use of agricultural reservoirs. By adopting the model in the case of reservoir called "O-Bongje," the optimum solution for such various objects as irrigation area, the amount of domestic water supply, the size of power generation, and the size of reservoir storage, etc., can be obtained. Second, by comparing the net benefits in each object under the changing condition of inflow into the reservoir, the factors which can most affect the yearly total net benefit can be drawn, and they are in the order of the amount of domestic water supply, irrigation area, and power generation. Third, the sensitivity analysis for the decision variable of irrigation which may have a first priority among the objects indicate that the effective method of water management can be rapidly suggested in accordance with a condition under the decreasing area of irrigation. Fourth, in the case of decision making on the water allocation policy in an existing multi-purpose reservoir, the rapid comparison of numerous alternatives can be possible by adopting the linear programming model. Besides, as the resources can be analyed in connection with various activities, it can be concluded that the linear programing model developed in this study is more quantitative than the traditional methods of analysis. Fifth, all the possible constraint equations, in using a linear programming model for adopting a water allocation problem in the agricultural reservoirs, are presented, and the method of analysis is also suggested in this study. Finally, as the linear programming model in this study is found comprehensive, the model can be adopted in any different kind of conditions of agricultural reservoirs for the purpose of analyzing optimum water allocation, if the economic and technical coefficients are known, and the decision variable is changed in accordance with the changing condition of irrigation area.

• Korean Journal of Environmental Agriculture
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• v.40 no.3
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• pp.211-218
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• 2021

BACKGROUND: Fine particulate matter (PM_2.5) is produced by chemical reactions between various precursors. PM_2.5 has been found to create greater human risk than particulate matter (PM₁₀), with diameters that are generally 10 micrometers and smaller. Ammonia (NH₃) and nitrogen oxides (NOx) are the sources of secondary generation of PM_2.5. These substances generate PM_2.5 through some chemical reactions in the atmosphere. Through chemical reactions in the atmosphere, NH₃ generates PM_2.5. It is the causative agent of PM_2.5. In 2017 the annual ammonia emission recorded from the agricultural sector was 244,335 tons, which accounted for about 79.3% of the total ammonia emission in Korea in that year. To address this issue, the agricultural sector announced the inclusion of reducing fine particulate matter and ammonia emissions by 30% in its targets for the year 2022. This may be achieved through analyses of its emission characteristics by monitoring the PM_2.5 and NH₃. METHODS AND RESULTS: In this study, the PM_2.5 concentration was measured real-time (every 1 hour) by using beta radiation from the particle dust measuring device (Spirant BAM). NH₃ concentration was analyzed real-time by Cavity Ring-Down Spectroscopy (CRDS). The concentrations of ozone (O₃) and nitrogen dioxide (NO₂) were continuously measured and analyzed for the masses collected on filter papers by ultraviolet photometry and chemiluminescence. CONCLUSION: This study established air pollutant monitoring system in agricultural areas to analyze the NH₃ emission characteristics. The amount of PM_2.5 and NH₃ emission in agriculture was measured. Scientific evidence in agricultural areas was obtained by identifying the emission concentration and characteristics per season (monthly) and per hour.

• Journal of Acupuncture Research
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• v.24 no.6
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• pp.1-14
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• 2007

Backgrounds : Rheumatoid Arthritis(RA) is known as the chronic inflammatory diseasethat induces persistent inflammation in the joint cavity. The destruction of cartilage occurs as the result of bones destoyed by pannus, several influential cytokines induced by the synovial capsulitis, varieties of proteinases, $O_2$ radicals, and the secondary degenerative changes of articular cartilage. The type 2 collagen-induced arthritis model is used in recent experimental research on rheumatoid arthritis. Cervus elaphus sibiricus (Nockyong) has the effect of relieving pain by nourishing the muscles, joints, and bones. It is also known to be efficacious in promoting and enhancing the immune system. The objective of this study was to investigate the effect of Cervus elaphus sibiricus herbal acupuncture to inhibit the generation of proinflammatory enzyme on type 2 collagen-induced arthritis. I investigated the inhibition of mRNA transcription of MIF(macrophage migration inhibitory factor), $TNF-{\alpha}$(Tumor necrosis $factor-{\alpha}$) and MMP-9 (matrix metalloproteinase-9) of Cervus elaphus sibiricus herbal acupuncture using an in vitro test. Also investigated was the inhibition of differentiation of Th 1 cells and activation of cytokines(MIF, $TNF-{\alpha}$, IL-6, MMP-9), which are known to cause initial RA ,and are also related to the morphology of the synovial membranes of the joint capsule, by an in vivo test, using CIA(collagen induced arthritis) model mice. Materials & methods : The laboratory animals used in this experiment were 4 week-old DBA female mice, weighing approximately 20 grams, and adjusted to the laboratory environment. The experiment was divided into the normal group(NOR)-no treated group, control group(CON)-CIA induced group, and sample group(SAM)-Cervus elaphus sibiricus herbal acupuncture treated group. RA was induced in the mice via injection of $50{\mu}{\ell}$ C II mixed CFA. The Cervus elaphus sibiricus herbal acupuncture solution was applied on $GB_{35}$(陽陵泉) for 26 days from the 3rd day of RA inducement. The concentration of the solution was determined via a MTT assay. To research the effect on the expression of MIF, $TNF-{\alpha}$ and MMP-9 mRNA, RT-PCR was performed on synovial membrane cells from the knee joint of CIA mice. C II induced RA knee joint's histo-chemical synovial membrane was observed using a specimen model via the Hematoxilin and Eosin dying technique. Results : The expression of mRNA of RA-related cytokines such as MIF, $TNF-{\alpha}$, and MMP-9 dosedependently decreased in the cell from the synovial membranes of the joint, which is treated with Cervus elaphus sibiricus herbal acupuncture solution. In mice treated with Cervus elaphus sibiricusherbal acupuncture, the damage of synovial membranes of the joint was lessened, and differentiation of Th 1 cells was suppressed. The activation of RA-related cytokines such as MIF was suppressed, and the generation of $TNF-{\alpha}$ and MMP-9 showed a statistically significant decreas. Conclusions : It is speculated that Cervus elaphus sibiricus herbal acupuncture has the therapeutic effect of palliating the damage of the tissue impaired by RA by inhibition of the initial RA progression and by regulating excessive differentiation of Th 1 cell as it suppresses the generation of RA-related cytokines during the highest stage of RA by acting on pro-inflammatory enzymes.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.577-583
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• 2000

The purpose of this study was to investigate the effectiveness of various quality preservative treatments for extending shelf life and maintaining good quality of minimally processed fruit and vegetables produced in Korea. To determine the suitable treatments for delaying quality deterioration, fresh Asian pears and Chinese cabbages were sliced and treated with various quality preservatives (1% CaCl$_2$, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan ＋1% vitamin C, 0.1% Sporix＋1% vitamin C, hot water (60$\^{C}$), 0.2% L-cysteine), packed with polyethylene film (60㎛-thick), and stored at 4$\^{C}$/0$\^{C}$ or 20$\^{C}$. Various biological and sensory tests were performed to evaluate the quality changes in minimally processed products. Results indicated that Chinese cabbages treated with 1% CaCl$_2$ at 4, and 1% CaCl$_2$ and 1% NaCl at 20$\^{C}$ were most effective in maintaining the quality and minimizing the biochemical changes during storage. For sliced Asian pears, 0.2% L-cysteine and 1% NaCl treatments were effective to reduce browning, and 1% CaCl$_2$ treatment was the most effective to prevent softening during storage at 20$\^{C}$ and 0$\^{C}$. Modified atmosphere packaging of Pleurotus ostreatus and Lentinus edodes had a significantly different shelf life depending on packaging material, packaging thickness and storage temperature. Sealed packaging with polyethylene film (60㎛-thick) for two kinds of mushrooms maintained a good quality with an extended shelf life by 30-50% at 20$\^{C}$ and by 30-130% at 0$\^{C}$. To minimize the quality deterioration which appeared in the condition of polyethylene film packaging, quality preservatives such as KMnO$_4$ and KHSO$_2$＋K$_2$S$_2$O$\_$5/ for SO$_2$ generation were added inside of mushroom packaging. The best condition for maintaining good quality longer was packaging with polyethylene film+SO$_2$ which showed 5080% extended shelf life for both Pleurotus ostreatus and Lentinus edodes at 20$\^{C}$ and 0$\^{C}$.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.265-272
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• 2002

In this study, we examined the effects of dietary fatty acids on the fatty acid composition of phospholipid fractions in regions of the brain and on behavioral development in rats. The Sprague Dawley rats were fed the experimental diets 3~4 wks prior to the conception. Experimental diets consisted of 10% fat(wt/wt) which were from either safflower oil (SO, poor in $\omega$3 fatty acids), mixed oil MO, P/M/S ratio : 1:1.4:1, $\omega$6/$\omega$3 ratio = 6.3), or mixed oil supplemented with vitamin E (+500 mg/kg diet). At 3 and 9 weeks of age, frontal cortex (FC), corpus striatum (CS), hippocampus (H), and cerebellum (CB) were dissected from the whole brain. The fatty acid content was determined in the different phospholipid fractions: phosphatidylcholine (PC), phosphatidyl-serine (PS), and phosphatidylethanolamine (PE) in the rat brain regions. In the visual discrimination test, the order of the cumulative errors made in Y-water maze test were SO > MO > ME. This suggested that the balanced diet supplemented with vitamin I had the most beneficial effect on learning ability. The overall characteristics of correlation between fatty acids and behavior development were that the frequency of cumulative errors were negatively correlated significantly with monounsaturated fatty acids (MUFAs), ie., 18:1 $\omega$9 and 22:1 $\omega$9. Docosa-hexaenoic acid (22:6 $\omega$3) of PS in frontal cortex (FC) was negatively correlated with the number of errors made in the Y-water maze test.22:5 $\omega$6 PS in hippocampus (H), PC and PE in corpus striatum (CS), PC in cerebellum (CB) were positively correlated with cumulative errors. And these errors were negatively correlated with 20:4 $\omega$ 6 of PE in corpus striatum (CS) and PC in cerebellum (CB). Especially, O1eic acid (18:1 u 9) in all phospholipid fractions (PC, PS, PE) of hippocampus was negatively correlated with the number of errors. These findings demonstrate that the MUFAs were might be essential for proper brain development, especially in hippocampus which is generally thought to be the regions of memory and learning.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.61-70
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• 2002

In order to investigate the classification and antibiotic resistance of Salmonella species,718 isolates were isolated from patient in Seoul from 1996 to 2001. The two hundred and ninety eight isolates (41.5%) were identified as Sal. Enteritidis, followed by Sal. Typhi 218 isolates (30.4%), and Sal. Typhimurium 87 isolates (12.1%). The identified Salmonella species were most resistant to tetracycline (32.7%), followed by streptomycin (28.0%), ticarcillin (18.1%) and ampicillin (12.4%). Among isolates,34.7% of Sal. Enteritidis were resistant to tetracycline, 32.3% to streptomycin,23.2% to ticarcillin,13.5% to ampicillin, respectively. 13.8% of Sal. Typhi were resistant to streptomycin,10.6% to tetracycline, respectively.66.7% of Sal. Typhimurium were resistant to tetracycline, 42.5% to streptomycin, 28.7% to ticarcillin, 26.4% to ampicillin and 17.2% to chloramphenicol, respectively. Of 718 isolates, 324 isolates (45.1%) were resistant to 1 or more drugs and 64 isolates (19.8%) were resistant to 1 drug, 132 isolates (40.7%) were resistant to 2 drugs,50 isolates (15.4%) were resistant to 3 drugs, 27 isolates (8.3%) to 4 drugs,27 isolates (8.3%) to 5 drugs,22 Isolates (6.8%) to 6 drugs. The most prevalent multiple resistant pattern was tetracycline-kanamycin (35.5%), followed by tetracycline-kanamycin-ticarcillin (8.3%), and tetracycline-kanamycin-ticarcillin-ampicillin (7.4%) . Antibiotic resistant rate of Sal. Typhimurium was 73.6%,1311owe4 by Sal. Enteritidis 53.7% and Sal. Typhi 19.3%. Most Sal. Enteritidis was resistant to 1 drug o.2 drugs, whereas Sal. Typhi. and Sal.. Typhunurium were more .resistant to 5 (16.7%) or 6 drugs (26.6%). The old generation antibiotics such as ampicillin, tetracycline, and streptomycin were annually more resistant than the new generation antibiotics such as ceftriaxone, ciprofloxacin or cefoxitin.

• Resources Recycling
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• v.19 no.2
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• pp.45-53
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• 2010

During the biomass gasification, tar generation is typically accompanied, which causes many problems, such as pipe plugging and equipment fouling. In the experiments, activated carbon was applied to the upper reactor of the two-stage gasifier in order to remove the tar generated during gasification. In addition, the effects of the upper-reactor temperature and equivalence ratio on the producer gas characteristics (composition, tar content and lower heating value) were investigated. To investigate the effect of the upper reactor-temperature, experiments were performed at 743, 793, $838^{\circ}C$, respectively. To examine the influence of the equivalence ratio, a comparison experiment was carried out at a equivalence ratio of 0.17. In all experiments, tar contents in the producer gases were below $2mg/Nm^3$. The maximum LHV of the producer gas was above $10MJ/Nm^3$, which is much higher than the typical LHV($3\sim6MJ/Nm^3$) in the air gasification of biomass.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.400.1-400.1
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• 2016

Interfacial engineering approaches as an efficient strategy for improving the power conversion efficiencies (PCEs) of inverted polymer solar cells (iPSCs) has attracted considerable attention. Recently, polymer surface modifiers, such as poly(ethyleneimine) (PEI) and polyethylenimine ethoxylated (PEIE), were introduced to produce low WF electrodes and were reported to have good electron selectivity for inverted polymer solar cells (iPSCs) without an n-type metal oxide layer. To obtain more efficient solar cells, quantum dots (QDs) are used as effective sensitizers across a broad spectral range from visible to near IR. Additionally, they have the ability to efficiently generate multiple excitons from a single photon via a process called carrier multiplication (CM) or multiple exciton generation (MEG). However, in general, it is very difficult to prepare a bilayer structure with an organic layer and a QD interlayer through a solution process, because most solvents can dissolve and destroy the organic layer and QD interlayer. To present a more effective strategy for surpassing the limitations of traditional methods, we studied and fabricated the highly efficient iPSCs with mono-layered QDs as an effective multi-functional layer, to enhance the quantum yield caused by various effects of QDs monolayer. The mono-layered QDs play the multi-functional role as surface modifier, sub-photosensitizer and electron transport layer. Using this effective approach, we achieve the highest conversion efficiency of ~10.3% resulting from improved interfacial properties and efficient charge transfer, which is verified by various analysis tools.

• Archives of design research
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• v.20 no.3 s.71
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• pp.289-298
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• 2007

The EGI system is a new communication method in limelight for helping disabled users to input and handle information on the computer more easily. However, due to the EGI system's "JEM(Jittery Eye Movements)" generation, it actually increases heavy psychological and physiological stresses for the user to input or perceive the target information on a machine. This study illustrates how to resolve this "JEM" issue and suggests a method that is easy and simple to be controled by anyone. A demo tool was built and tested to find and prove the reasons for "JEM" This test shows that that the case with snap up is less stressful than without to input text as a final result of the test evaluation in both psychological snap up and physiological brain wave test. Postnatal or naturally acquired, it is found that the disabled can have opportunities for smoother communication, and a possible efficient system development for better communication.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.293-299
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• 2004

The current investigation was carried out to find out the anticancer activity of the methanol extract from Buplerum falcatum against cancered ICR mouse and cancer cell lines such as J774A.1 and L1210 cells. Extract of Buplerum falcatum displayed the considerable augmentation(134%) of the survival of ICR mouse bearing Sarcoma 180 cancer. In addition, the cytotoxic effects of methanol extract of Buplerum falcatum against J774A.1 cells and L1210 cells were found to show $IC_{50}$ values of $57.3\;{\mu}g/ml$ and $54.6\;{\mu}g/ml$, respectively. In contrast to such cytotoxicity against cancer cells, the extract exerted only meagre toxicity against normal lymphocytes. The increased generation of $O_2^-$ and the considerably increased activities of super-oxide dismutase(SOD) and glutathione peroxidase(GPx) of both J774A.1 cells and L1210 cells in the presence of Buplerum falcatum extract implied that the observed cytotoxicities may have resulted from the detrimental effect of reactive oxygen species(ROS) evoked by Buplerum falcatum extract on the cancer cells.