• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.16-22
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• 2007

In order to evaluate the hepatoprotective effect of an herb distillate, ie., a mixture of 28 traditional Korean herbs, germanium, tormarine and Gijangsoo (Gijang water), $CCl_4$ was intraperitoneally administered to rats before or after supplementation of the diluted herb distillate (HD) for 2 weeks. Then hepatic xanthine oxidase activity and serum lipid profiles were determined. The experimental groups had higher feed intake than the normal control (NC), but had lower weight gain. Water intake and the amount of feces were not significantly different, but urine was excreted in lower amounts in all the experimental groups compared to the NC. Liver weights in the HD-supplemented groups were lower than that of the distilled water-supplemented groups (DW-groups) after $CCl_4$-administration. Serum ALT activities in all the experimental groups were higher than that of the NC-group. However, the increasing activity of serum ALT in the HD-supplemented groups (HD-groups) was lower than that of the DW-groups. Total serum and LDL-cholesterol levels were higher in all the $CCl_4$-administered groups than in the NC-groups, and serum HDL-cholesterol levels were lower in all the experimental groups compared with the NC-groups. Meanwhile, the increasing rate of total serum and LDL-cholesterol levels and the decreasing rate of HDL-cholesterol in the HD-groups were lower than that of the DW-groups. But, levels of serum TG were similar among all the experimental groups. The activities of hepatic xanthine oxidase (XOD) type O of the $CCl_4$-administered rats showed a significant increase in and an increasing rate of XOD in the HD-groups, which was lower than that of the DW-groups. On the other hand, GST activities in all the experimental groups were significantly decreased, and the decreasing rate was lower in the HD-groups than in the DW-groups. The hepatic contents of GSH and LPO in all the rats were not changed by $CCl_4$ administration. These results suggest that the decreased liver damage in the HD-supplemented groups was due to the inhibition of XOD-type O activity by constituents of HD, as well as by a prevention/inhibition of serum lipid profile changes in $CCl_4$-treated rats. However, further detailed studies are needed to support this hypothesis.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.739-746
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• 2008

The aim of this study is finding the optimal design parameters and the optimal operation variables of a reactive distillation column. Different from steady state optimization, dynamic optimization makes it possible considering operation ability as well as design problems at process design step. For performing dynamic optimization, dynamic simulation should be done first. If dynamic simulation is already finished, dynamic optimization can be performed with less effort than that of dynamic simulation.Reactive distillation systems involving reaction and separation in a single unit have the potential to reduce capital and operating costs, particularly when reaction have conversion constraint or when azeotropes exist making conventional separation difficult and expensive. This study here present work on the continuous distillation process, the homogeneous catalyzed esterification of methanol and acetic acid, the synthesis of methyl acetate. Based on an equilibrium stage model of a reactive distillation column a dynamic optimization problem was formulated and solved. And the results were verified by performing dynamic simulation and showing the variation of conversion and purity as the variation of the operation variables. As the results of dynamic optimization, this study found optimal feed ratio, reflux ratio and reboiler duty of this system. And as this study applied it to dynamic simulations the dynamic characteristics of a reactive distillation column are showed under optimal operating condition.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.1-34
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• 2008

It is recognized that RPS(Renewable Portfolio Standard) and FIT(Feed-in Tariff) are two main policy instruments to promote Renewable Electricity(RE). The Korean Government announced in 2008 that RE promotion scheme will be changed to RPS from current FIT system in 2012. But we believe RPS is inferior to FIT for promoting less developed technologies such as photovoltaics or wind power. This is because the achievement of RE promotion in countries adopting RPS is markedly worse than that in European counties or Janpan adopting FIT. If the policy change is inevitable, when considering the lessons from Japan's failure as well as supporting the less developed technologies, it is recommended that either the market should be divided into several technology and scale categories, or more RPS-Credit per kWh should be assigned to the photovoltaic and wind power than instead of letting the all technologies compete in the "open category". It is also recommended that (1) Renewable Energy Promotion Fund(tentative name) based on a part of current energy related tax revenue should be introduced, or (2) cost of supporting the Renewable Electricity should automatically be transferred into the electricity bill of electricity consumers following the German System.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.469-476
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• 1998

In the case of acquisition and displaying medical Images such as ultrasonography and endoscopy on VGA monitor of PC system, image degradation of tear-drop appears through scan conversion. In this study, we compare several methods which can solve this degradation and implement the hardware system that resolves this problem in real-time with PC. It is possible to represent high quality image display and real-time processing and acquisition with specific de-interlacing device and PCI bridge on our hardware system. Image quality is improved remarkably on our hardware system. It is implemented as PC-based system, so acquiring, saving images and describing text comment on those images and PACS networking can be easily implemented.metabolism. All images were spatially normalized to MNI standard PET template and smoothed with 16mm FWHM Gaussian kernel using SPM96. Mean count in cerebral region was normalized. The VOls for 34 cerebral regions were previously defined on the standard template and 17 different counts of mirrored regions to hemispheric midline were extracted from spatially normalized images. A three-layer feed-forward error back-propagation neural network classifier with 7 input nodes and 3 output nodes was used. The network was trained to interpret metabolic patterns and produce identical diagnoses with those of expert viewers. The performance of the neural network was optimized by testing with 5~40 nodes in hidden layer. Randomly selected 40 images from each group were used to train the network and the remainders were used to test the learned network. The optimized neural network gave a maximum agreement rate of 80.3% with expert viewers. It used 20 hidden nodes and was trained for 1508 epochs. Also, neural network gave agreement rates of 75~80% with 10 or 30 nodes in hidden layer. We conclude that artificial neural network performed as well as human experts and could be potentially useful as clinical decision support tool for the localization of epileptogenic zones.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.144-150
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• 2013

Hybrid ceramic membrane (HCM) processes that combined ozonation with a ceramic membrane (CM) or a reactive ceramic membrane (RM), an iron oxide nanoparticles (IONs) incorporated-CM were investigated for membrane fouling control. Alumina disc type microfiltration and ultrafiltration membranes doped with IONs by sintering method were tested under varying mass fraction of IONs. Scanning electron microscope (SEM) images showed that IONs were well-doped on the CM surface and doped IONs were approximately 50 nm in size. Change in the pure water permeability of RM was negligible compared to that of CM. These results indicate that IONs incorporation onto CM had little effect on CM performance in terms of the flux. Natural organic matter (NOM) fouling and fouling recovery patterns during HCM processes confirmed that the RM-ozonation process enhanced the destruction of NOM and reduced the extent of fouling more than the CM-ozonation process by hydroxyl radical formation in the presence of IONs on RM. In addition, analyses of NOM in the feed water and the permeate showed that the efficiency of membrane fouling control results from the NOM degradation during HCM processes; leading to removal and transformation of relatively high contents of aromatic, high molecular weight and hydrophobic NOM fractions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.601-607
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• 2002

The present study was designed to examine how sea tangle intake contributes to the content of bone calcium and breaking force of femur with growing female rats. Weaned rats were fed on experimental diets consisting in four levels of sea tangle powder; $0\%$ (control), $0.5\%$, $1.0\%$ and $1.5\%$ for 4 and 8 weeks. Body weight gain and feed intake were not significantly affected by added amount of sea tangle. Bone breaking strength, ash content and calcium levels of the femur of rats fed on diets with sea tangle were higher than those of control groups (p<0.05). But moisture content weight and length of femur did not show any significant difference among groups. TP, ALB, TC, TG, AIP, osteocalcin, GOT and GPT levels in serum did not show any significant difference through the total feeding period but calcium and phosphorus contents of serum increased with increase in feeding period, significantly in $0.05\%$ level by added amounts of sea tangle. Calcium levels in feces increased significantly (P<0.05), but ash levels were not changed significantly by added amount of sea tangle. We could expect from this results that the ingestion of sea tangle (Kjellemaniella crassifolia) could be helpfull to increase bone calcium content and calcium absorption as well as to intensify the femur stength and to increase the calcium content of rats.

• Resources Recycling
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• v.7 no.3
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• pp.17-26
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• 1998

A study on the recovery of silver and nitric acid in the liquid waste resulted from the mediated electrochemical oxidation(MEO) process was conducted. The removal of silver in the concentrated nitric acid solutions was carried out by the electrodeposition. The removal efficiency more than 98% could be obtained in nitric acid concentrations less than 3 M with the current efficiency of nearly 100%. The experimonts on the evaporation for the recovery of nitric acid were performed as well. At the evaporation factor of 25., the degree of nitric acid recovery in 3.5 M nitric acid solution containing 0.5 to 1.0 mol% NaNO, was 80~90% resulting in 2.8~3.1 M nitric acid. The design factors and operating conditions of the distillation tower were analyzed by using MEH model derived by Maphtali-Sandholm with the throughput of 4 kg/hr for the enrichment of dilute nitric acid solution recovered by evaporation to reuse in the MEO process. The distillation column composed of eleven theoretical stages having the overall tray efficiency of 70% are needed to obtain 1.03 kg/h of 12M nitric acid and 2.97 kg/h of water with feed being introduced to the column at tray 6 from the bottom at the reflux ratio of 0.25, the reboiler with the heat load of 2.7 kW, and the condenser with the cooling load of 0.5 kW.

• Korean Journal of Poultry Science
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• v.27 no.2
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• pp.115-132
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• 2000

Eggshell strength and eggshell pigmentation are described in this paper since these are needed for quality egg production. A strong eggshell is determined by the components of the shell (cuticle, true shell and membranes) as well as the proper function of the gastrointestinal tract, the shell gland, the Kidneys and the endocrine system. When the puller reaches sexual maturity, the medullary bone must be ready for the laying hen at the peak egg shell formation. The amount of calcium in the layer diet, sources of calcium feed, the ratio of calcium and phosphorus in the layer diet, adequate levels of vitamin D and the dietary mineral (electrolyte) balance in the body fluid are important factors along with the levels of other nutrients. Biological, environmental and managerial factors such as the age of laying flock, temperature and humidity of the hen house, bird strain, disease, egg collection through transportation and others and influence the shell breakage at various stages of movement of the eggs from the producer to the consumer. The pigments present in eggshells are protoporphyrin-Ⅸ, biliverdin-Ⅸ and its zinc chelate and occasional traces of coproporphyrin-Ⅲ. However, there are several causes of changes in eggshell pigmentation such as the age of hen, disease, drugs and surface defects due to abnormal post-cuticular deposits.

• Journal of the Korean Society of Food Culture
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• v.3 no.4
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• pp.397-406
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• 1988

The changes in the dietary pattern of Koreans during the last one century and its consequences are summarized as follows; 1. Until the beginning of 20th century, Koreans used variety of cereals, vegetables and fruits for their staple food, but the variety has been largely reduced by the agricultural development and urbanized life style. 2. The well balanced traditional dietary pattern of Korean had been deeply deteriorated by the food shortage during the Japanese occupation and Korean war. 3. The deteriorated nutritional condition of Korean was not remedied by the restoration of traditional dietary pattern, but attempted to overcome it by the adoption of Western food habit. 4. The people were trained to eat milk and flour-meals during the starvation of Korean war, and it was continued after Korean war through the animal husbandry promotion policy. 5. The importation of food and feed cereals has been increased rapidly during the economic growth in 1970's and the food self-sufficiency droped below 50%. 6. In 1970's, the food supply pattern of Korean was restored to the level of early 1900, but the consumption of lipid increased extraordinarily. 7. The overconsumption of animal food and lipid continues in 1980's, and it coincides with the rapid increase in the occurence of food related degenerative deseases. 8. The establishment of Korean dietary goal which is based on the traditional dietary pattern is needed.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.43-50
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• 2007

Veterinary antibiotics have been widely used to increase feed efficiency, to prevent disease, and to promote growth as well as to control disease. The antibiotics administered can be excreted through the urine and feces. One of the major routes of veterinary antibiotics entering soil and water environment is via the application of animal manure to agricultural land as an organic fertilizer source. Since little is known about impacts of antibiotics on the environment, this study was conducted to prioritize the veterinary antibiotics based on the consumption and potential to reach the environment. Among 83 veterinary antibiotics consumed in Korea, ten antibiotics were used at the greater dose than 25 Mg in 2004. Potential to reach the environment was determined according to excretion rate after administered to animals and sorption affinity to soil solids after applied to agricultural land. Seventeen antibiotic active ingredients (Ais) were classified as 'High' priority in terms of the potential to reach the environment. An overall priority score was determined by combining priority score based on consumption with the degree of potential environment exposure. Twenty veterinary antibiotic AIs were classified as 'Very high' or 'High' priority requiring detailed assessment. The antibiotic AIs were identified four aminoglycosides, two macrolides, two penicillins, five sulfonamides, three tetracyclines, two quinolones, and two miscellaneous. Eight veterinary antibiotic AIs including amoxicillin, carbadox, chlortetracycline, neomycin, oxytetracycline, sulfamethazine, sulfathiazole, and tylosin were identified to have a greater priority of environmental risk in Korea.