• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.86-93
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• 2014

Mesoporous tin oxide (meso-$SnO_2$) with 5 nm mesopore and well-aligned $SnO_2$ nanowire-bundles with 5~7 nm diameters were prepared by template synthesis method. In addition to meso-$SnO_2$, meso-$SnO_2$/$SiO_2$, which has almost the same structure as meso-$SnO_2$ including $SiO_2$ used as the template were prepared by the modification of template synthesis. X-ray diffraction, N2 adsorption-desorption isotherms, transmission electron microscopy observed structures of meso-$SnO_2$ and meso-$SnO_2$/$SiO_2$. Although the meso-$SnO_2$/$SiO_2$ showed some positive evidences to suppress the volume change of meso-$SnO_2$ through cyclic voltammogram, electrochemical impedance spectroscopy, and voltage profiles during cycling, its cycle life was not improved highly to address modified structural effects. Thus, further study might be done to control the nanostructure of meso-$SnO_2$/$SiO_2$ for enhanced cycle performance.

• Journal of Korea Water Resources Association
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• v.37 no.3
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• pp.219-231
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• 2004

The use of air diffuser system to ameliorate the reservoir by breaking stratification is now widespread. This study focuses on the hydrodynamic behavior of bubble plumes, which is the major mechanism of destratification and their combined effect of adjacent plumes on destratification efficiency. By introducing 2-phase Computational Fluid Dynamics(CFD) technique, we could suggest the optimal diffuser spacing having optimal destratification efficiency by simply analyzing the complex destratification procedures varying with the seasonal stratification intensity and bubble flow rate. Lab experiments were also carried out to verify CFD model in thermally stratified fresh water which quite differs from former researches using salts. This study showed that the mixing efficiency strongly depends on the spacing of neighboring plumes. When diffuser spacing is lower than 1.5 times the depth, the combined effect is stronger; as Plume Number(PN) is increased, the efficiency is strongly affected by spacing. If the distance is shorter than the depth of water, the efficiency increases linearly in proportion to PN. Otherwise, the efficiency increases non-linearly. These findings suggest that the combined effect should be more quantitatively taken into consideration for design and operation of air-diffuser destratification system, and recommend that the optimal destratification efficiency will be when plume number is 1000 and the spacing between neighboring diffusers is 1.5 times the depth.

• Journal of Korea Water Resources Association
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• v.39 no.2 s.163
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• pp.161-178
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• 2006

Heathcote (1998) identified a systematic, seven-step approach to general watershed planning and management. It consists of 1) understanding watershed components and processes, 2) identifying and ranking problems to be solved, 3) setting clear and specific goals, 4) developing a list of management options, 5) eliminating infeasible options 6) testing the effectiveness of remaining feasible options, and 7) developing the final options. In this study the first five steps of that process were applied to the Anyangcheon watershed in Korea, which experiences streamflow depletion, frequent flood damages, and poor water quality typical of highly urbanized watersheds. This study employed four indices: Potential Flood Damage(PFD), Potential Streamflow Depletion(PSD), Potential Water Quality Deterioration(PWQD) and Watershed Evaluation Index(WEI) to identify and quantify problems within the watershed. WEI is the integration index of the others. Composite programming which is a method of multi-criteria decision making is applied for the calculation of PSD, PWQD and WEI (Step 2). The primary goal of the study is to secure instreamflow in the Anyangcheon during dry seasons. The second management goals of flood damage mitigation and water quality enhancement are also set (Step 3). Management options include not only structural measures that can alter the existing conditions, but also nonstructural measures that rely on changes in human behavior or management practices (Step 4). Certain management options which are not technically, economically, and environmentally feasible, are eliminated (Step S). Therefore, this study addresses a Pre-feasibility study, which established a master plan using Steps 1 through 5.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.4
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• pp.286-294
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• 2014

The purpose of this study is to investigate the effects of applying density current generator (hereafter referred to as DCG to large lakes on the operating conditions of DCG, de-stratification, water quality improvement and inhibition of algae occurrence. As a result of a survey conducted to derive the optimum operating parameters of DCG in a condition to minimize eco-toxicity, the following conclusions were obtained. During the survey period, a marked stratification appeared in September to October 2011 and May 2012. At this time, the average depth of water to form thermocline was found to be $5{\pm}2$ m, so the location of discharge port for the operation of DCG was determined to be about 5 m below from the surface. To minimize the adverse effects of benthos and obtain the effect of water mixture at the time of water circulation, the mixing ratio of surface water and deep water was designed to be 3:1 by means of ecotoxicological assessment on the DCG operating characteristics. To select the appropriate operating hours for DCG, DCG was operated by 12 hr, 24 hr, 36 hr and 48 hr. As its result, the formation of thermocline did not occur during the operation of 36 hr. Also, It was effected that start reoperating from 3rd day after stop 2days under the condition of operated during 36 hr with calculated power consumption. Under the above conditions, the results of DO and water temperature analysis during the operation of DCG showed that the stratification, which was distinct previously, appeared to be weak, and relatively lower levels than those before operation were found as a result of water quality analysis on COD and chlorophyll-a, which leads to the conclusion that the water body is maintained at a stable condition due to the circulation of water by the occurrence of density current resulting from the operation of DCG.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.643-650
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• 2007

It has been known that Samultang has positive effects on blood circulation and erythrocyte formation. Samultang was composed of four ingredients, Angelica gigas Nikai, Rahmanniae Radix Preparata, Paeonia lactiflora Pallas, and Cnidium officinale Makino. Five types of bread were prepared by replacing water with Samultang for dough proportionally. Control (C) did not have Samultang and the other four experimental bread contained Samultang: S-I (25% of water was substituted by Samultang), S-II (50% substituted), S-III (75% substituted), and S-IV (100% substituted). Moisture, protein, and ash contents of Samultang were $97.34{\pm}0.11%,\;0.42{\pm}0.04%,\;and\;1.40{\pm}0.16%$, respectively. Replacing water with Samultang decreased pH and increased significantly wet gluten content of the dough. Substitution of Samultang for water incremented redness and yellowness of the dough and bread and increased hardness. It also raised the contents of ash and protein. Although it was not significant, in addition, moisture loss of the bread during storage seemed to be lessened by replacing water with Samultang. However, total volume and specific loaf volume of the bread, baking loss rate, and the other textural characteristics except hardness were not affected by substituting water with Samultang. Due to the above results, sensory evaluation of volume and gumminess of the bread were improved significantly by substituting Samultang for water. The bread replaced 25% of the water with Samultang was ranked as the best by the test of sensory evaluation. These results imply that adding Samultang instead of water to dough for bread might bring positive effects on quality characteristics of the bread without any adverse influences. Therefore, it might be worth developing functional bread using Samultang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.839-846
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• 2004

The purpose of this study was to investigate the possibility of medicinal plants application as an edible functional food resource. This research was planned to apply Artesmisia capillaris, which is one of the most widely used oriental medicinal resource into beverages, and to evaluate the validity and the nutrients of the developed beverage with Artemisia capillaris. Following this plan, we analyzed contents of the general nutritional composition, mineral and amino acid contents. And to evaluate the improvement of blood circulation and the ability to recover from fatigue, we had a group of athletes to regularly take the beverage before and after exercise and checked the heart rates, and blood components before exercise and after exercise. Brix, pH and titratable acidity of develoued drink were 9.2%, 4.4 and 0.04%, respectively. The approximate nutritional composition of beverage was carbohydrate, 2.70%, crude protein, 6.00%, crude ash, 0.20%, and crude fat, 0.10%. And developed beverage contained essential amono acids and minerals (p, Ca, K, Na, Fe, Mn, Zn). Heart rates, lactic acid, glucose, creatinine, LDH, GOT, GPT and lipid concentratios in blood were decreased after taking the beverage with Artemisia capillaris for 6 weeks, both in stable condition and after exercise. Since the athletes who participated In our research were doing aerobic exercise regularly, we judged that this result was formed not only by aerobic exercise, but also by the function of developed beverage with Artemisia capillaris the athletes took for 6 weeks. We believe that taking the beverage regularly will help the improvement of the public health and the athleticism of the athletes. We hope that this result will be used as the basic resource in developing of the beverage with Artemisia capillaris in the near future.

• Journal of Life Science
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• v.31 no.3
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• pp.346-355
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• 2021

The purpose of this study was to evaluate the possibility that administration of Bacillus polyfermenticus KJS-2 (BP2), Bacillus mojavensis KJS-3 (Moja3), and their mixtures could control serum lipid levels. We observed changes in the blood cell level, metabolic function evaluation, and blood lipid levels after two weeks of oral administration of these microbial strains to hyperlipidemia-induced rats. Measurements of major cell changes in the white blood cells (WBC) indicated no significant effects due to the administration of the microbial strains. Platelet (PLT) levels decreased by 18.4% in the Triton WR-1339-treated group (NCON) and recovered to the control (CON) group levels in the positive control (PCON) group and the microbial strain-administered groups (p<0.05). No functional changes were observed in red blood cells (RBC) by Triton WR-1339-induced hyperlipidemia. The blood AST, ALT, BUN, and creatinine levels did not indicated effects on liver and kidney function, and all rats administered the microbial mixture recovered. The blood lipid levels in the microbe-treated groups indicated reduced levels of triglyceride (TG) and total cholesterol (TC), and increased levels of serum HDL cholesterol. The HMG-CoA inhibition rate of 7-O-succinyl macrolactin A (SMA) produced by BP2 showed similar activity at a concentration of 1,000 times lower than that achieved with atorvastatin. The administration of the microbial strains to the Triton WR-1339-induced rat model of hyperlipidemia resulted in reduced weight gain without affecting the food and water intake. Thus, blood circulation can be improved by controlling serum lipid levels by the combined administration of the BP2 and Moja3 microbial strains.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.196-201
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• 2023

In this study, a CNT fiber flexible electrode grafted with CuO nanoparticles (CuO NPs) and polyaniline (PANI) was developed and applied to a nonenzymatic electrochemical sensor for H₂O₂ detection. CuO NPs/PANI/CNT fiber electrode was fabricated through the synthesis and deposition of PANI and CuO NPs on the CNT fiber surface using an electrochemical method. Surface morphology and elemental composition of the CuO NPs/PANI/CNT fiber electrode were characterized by scanning electron microscope with energy dispersive X-ray spectrometry. And its electrochemical characteristics were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). Compared with a bare CNT fiber as a control group, the CuO NPs/PANI/CNT fiber electrode showed a 4.78-fold increase in effective surface area and a 8.33-fold decrease in electron transfer resistance, which leads to excellent electrochemical properties such as a good electrical conductivity and an efficient electron transfer. These improved characteristics were due to the synergistic effect through the grafting of CNT fiber, PANI and CuO NPs. As a result, this electrode enhanced the H₂O₂ sensing performance.

• Information Systems Review
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• v.25 no.1
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• pp.129-143
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• 2023

In the era of big data, the field of artificial intelligence is showing remarkable growth, and in particular, the image classification learning methods by deep learning are becoming an important area. Various studies have been actively conducted to further improve the performance of CNNs, which have been widely used in image classification, among which a representative method is the Convolutional Recurrent Neural Network (CRNN) algorithm. The CRNN algorithm consists of a combination of CNN for image classification and RNNs for recognizing time series elements. However, since the inputs used in the RNN area of CRNN are the flatten values extracted by applying the convolution and pooling technique to the image, pixel values in the same phase in the image appear in different order. And this makes it difficult to properly learn the sequence of arrangements in the image intended by the RNN. Therefore, this study aims to improve image classification performance by proposing a novel hybrid method of CNN and RNN applying the concepts of encoder and decoder. In this study, the effectiveness of the new hybrid method was verified through various experiments. This study has academic implications in that it broadens the applicability of encoder and decoder concepts, and the proposed method has advantages in terms of model learning time and infrastructure construction costs as it does not significantly increase complexity compared to conventional hybrid methods. In addition, this study has practical implications in that it presents the possibility of improving the quality of services provided in various fields that require accurate image classification.

• Journal of Ginseng Research
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• v.29 no.1
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• pp.1-18
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• 2005

Ginseng Radix, the root of Panax ginseng C. A. Meyer has been used in Eastern Asia for 2000 years as a tonic and restorative, promoting health and longevity. Two varieties are commercially available: white ginseng(Ginseng Radix Alba) is produced by air-drying the root, while red ginseng(Ginseng Radix Rubra) is produced by steaming the root followed by drying. These two varieties of different processing have somewhat differences by heat processing between them. During the heat processing for preparing red ginseng, it has been found to exhibit inactivation of catabolic enzymes, thereby preventing deterioration of ginseng quality and the increased antioxidant-like substances which inhibit lipid peroxide formation, and also good gastro-intestinal absorption by gelatinization of starch. Moreover, studies of changes in ginsenosides composition due to different processing of ginseng roots have been undertaken. The results obtained showed that red ginseng differ from white ginseng due to the lack of acidic malonyl-ginsenosides. The heating procedure in red ginseng was proved to degrade the thermally unstable malonyl-ginsenoside into corresponding netural ginsenosides. Also the steaming process of red ginseng causes degradation or transformation of neutral ginsenosides. Ginsenosides $Rh_2,\;Rh_4,\;Rs_3,\;Rs_4\;and\;Rg_5$, found only in red ginseng, have been known to be hydrolyzed products derived from original saponin by heat processing, responsible for inhibitory effects on the growth of cancer cells through the induction of apoptosis. 20(S)-ginsenoside $Rg_3$ was also formed in red ginseng and was shown to exhibit vasorelaxation properties, antimetastatic activities, and anti-platelet aggregation activity. Recently, steamed red ginseng at high temperature was shown to provide enhance the yield of ginsenosides $Rg_3\;and\;Rg_5$ characteristic of red ginseng Additionally, one of non-saponin constituents, panaxytriol, was found to be structually transformed from polyacetylenic alcohol(panaxydol) showing cytotoxicity during the preparation of red ginseng and also maltol, antioxidant maillard product, from maltose and arginyl-fructosyl-glucose, amino acid derivative, from arginine and maltose. In regard to the in vitro and in vivo comparative biological activities, red ginseng was reported to show more potent activities on the antioxidant effect, anticarcinogenic effect and ameliorative effect on blood circulation than those of white ginseng. In oriental medicine, the ability of red ginseng to supplement the vacancy(허) was known to be relatively stronger than that of white ginseng, but very few are known on its comparative clinical studies. Further investigation on the preclinical and clinical experiments are needed to show the differences of indications and efficacies between red and white ginsengs on the basis of oriental medicines.