• Economic and Environmental Geology
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• v.37 no.1
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• pp.61-72
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• 2004

The soil samples were collected from the paddy field near the mine tailing dumps in the abandoned Duckum mine in Korea. In the laboratory, the soil solution was extracted from the soil using centrifuge, and analysed for the chemical composition. Physical and chemical soil properties were also analysed. Kaolinite is the main clay minerals in the paddy soil and the CEC value is therefore relatively low. Nearly all soil samples show enrichment in their trace elemental concentrations(Cd, Cu, Pb and Zn) compared with natural background level. Some soil samples exceed the soil remediation intervention values for Cd, Pb and Zn and target value for Cu, when compared with Dutch standard, whereas As, Ni and Cr are in normal range. Lead concentrations in some samples near the mine tailing dumps also exceed the standard for remediation act for agricultural area set by Korean soil conservation law. The trace elemental concentrations are higher in the paddy soil nearer the mine tailing dumps and lower for the samples from distance. Similar trend with distance is found for the soil solution chemistry but the decrease with distance from the mine tailing dumps are sharper than the changes in soil chemistry. Cadmium, Cu and Pb concentrations in the soil solution are very low, ranging from a tenth and hundredths to a maximum of several mg/l, whereas their concentrations in soils are highly enriched for natural background. Most of the trace elements are thought to be either removed by reduced iron sulphides or iron oxides, depending on the redox changes. Geochemical equilibrium modelling indicate the presence of solubility controlling solid phases for Cd and Pb, whereas Zn and Cu might have been controlled by adsorption/desorption processes. Although pollutants migration through solution phase are thought to be limited by adsorption onto various Fe, Mn solid phases, the pollutants exist as easily releasable fractions such as exchangeable site. In this case, the paddy soil would act as pollutant pool, which will supply to plants in situ. whenever the geochemical conditions favour.

• The Journal of Engineering Geology
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• v.22 no.1
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• pp.95-111
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• 2012

This study investigated the relationship between the geochemical environment and the occurrence of natural radioactive materials (uranium and Rn-222) in borehole groundwater at an Icheon site. The drill core recovered from the study site consists mainly of biotite granite with basic dykes. The groundwater samples were collected at four different depths in the borehole using the double-packed system. The pH range of the groundwater was 6.5~8.6, and the chemical type was Ca-$HCO_3$. The ranges of uranium and Rn-222 concentrations in the groundwater were 8.81~1,101 ppb and 5,990~11,970 pCi/L, respectively, and concentrations varied greatly with depth and collection time. The ranges of uranium and thorium contents in drill core were 0.53~18.3 ppm and 6.66~17.5 ppm, respectively. Microscope observations and electron microprobe analyses revealed the presence of U and Th as substituted elements for major composition of monazite, ilmenite, and apatite within K-feldspar and biotite. Although the concentration of uranium and thorium in the drill core was not high, the groundwater contained a high level of natural radioactive materials. This finding indicates that physical factors, such as the degree of fracturing of an aquifer and the groundwater flow rate, have a greater influence on the dissolution of radioactive materials than does the geochemical condition of the groundwater and rock. The origin of Rn-222 can be determined indirectly, using an interrelationship diagram of noble gas isotopes ($^3He/^4He$ and $^4He/^{20}Ne$).

• Journal of Dairy Science and Biotechnology
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• v.16 no.2
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• pp.119-136
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• 1998

The lipids of milk provide energy and many essential nutrients for the newborn animal. They also have distinctive physical properties that affect the processing of dairy products. Milk fat globules mainly consist of neutral lipids like triacylglycerols, whereas the globule membranes contain the complex lipids mostly, Phospholipids are a small but important fraction of the milk lipids and are found mainly in the milk fat globule membrane and other membranous material in the skim-milk phase. The milk fats of ruminant animals are characterized by the presence of relatively high concentrations of short-chain fatty acids, especially butyric and hexanoic acids, which are rarely found in milks of non-ruminants. The fatty acids of milk lipids arise from de novo synthesis in the mammary gland and uptake from the circulating blood. The fatty acid compositions of milks are usually complex and distinctive, depending on the nature of the fatty acids synthesized de novo in the mammary gland and those received from the diet in each species. The content and composition of milks from different species vary widely; presumably, these are evolutionary adaptations to differing environments. The actual process by which these globules are formed is unkonwn, but there are indications that triglyceride-containing vesicles which bleb from endoplasmic reticulum may serve as nucleation sites for globules. Recent studies on milk have centred on the manipulation of milk lipids to increase specific fatty acids, i.e. 20-carbon omega-3 fatty acids (eicosapentaenoic acid 20:5n3, decosahexaenoic acid 22:6n3) from marine sources because the fatty acids are closely associated with a decreased risk of coronary heart disease.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.254-263
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• 2007

The objective of this study was to evaluate biological water quality using fish assemblages in Nakdong River watershed. We selected 6 sites along the main axis of the river and evaluated the Index of Biological Integrity (IBI), Qualitative Habitat Evaluation Index (QHEI) and chemical water quality during July 2004${\sim}$March 2006. For the study, we applied the 10 metric IBI model, which was developed for national biological water quality criteria. Nakdong River's IBI value averaged 20.8 (n=14) during the study which means poor biological water quality. Physical habitat health at all sites, based on QHEI model, was measured as 110, indicating fair${\sim}$good condition. The habitat health varied depending on the locations sampled. Habitat health in sites 1 and 6 was judged as good, while the health in sites 3 and 4 was $poor{\sim}fair$. Especially, we found the metric values of $M1{\sim}M5$, M7, M10 were low in sites 3 and 4 compared to other sites. In these sites, thus, habitat restoration of substrate composition, riffles, and bank vegetation may be necessary. In the mean time, chemical water quality, based on BOD, COD, TSS, and nutrients, had no large spatial and temporal variations. Overall data analysis indicated that site 3 was largely impacted by the polluted-tributary, Keumho River and the downstreams showed better water quality due to the dilution of the polluted river water by Nam River and Hwang River.

• Journal of Biosystems Engineering
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• v.5 no.1
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• pp.1-14
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• 1980

Threshing operation may be one of the most important processes in the paddy post-production system as far as the grain loss and labor requirement are concerned . head-feeding type threshers commercially available now in Korea originally were developed for threshing dry paddy in the range of 15 to 17 % in wet basis. However, threshing wet-paddy with the grain moisture content above 20 % has been strongly recommended, especially for new high-yielding Indica -type varieties ; (1) to reduce high grain loss incurred due to the handling operations, and (2) to prevent the quantitative and qualitative loss of milled -rice when unthreshed grains are rewetted due to the rainfall. The objective of this study were to investigate the adaptability of both a head-feeding type thresher and a throw-in type thresher to wet-paddy , and to find out the possiblilities of improving the components of these threshers threshing. Four varieties, Suweon 264 and Milyang 24 as Tongil sister line varieties, minehikari and Jinhueng as Japonica-type varieties, were used at the different levels of the moisture content of grains. Both the feed rate and the cylinder speed were varied for each material and each machine. The thresher output quality , composition of tailing return, and separating loss were analyzed from the sampels taken at each treatment. A separate experiment for measurement opf the power requirement of the head-feeding type thresher was also performed. The results are summarized as follows : 1. There was a difference in the thresher output quality between rice varieties. In case of wet-paddy threshing at 550 rpm , grains with branchlet and torn heads for the Suweon 264 were 12 % and 7 % of the total output in weight, respectively, and for the Minehikari 4.5 % and 2 % respectively. In case of dry paddy threshing , those for the Suweon 264 were 8 % and 5% , and for the Minehikari 4% and 1% respectively. However, those for the Milyang 23 , which is highly susceptable to shattering, were much lower with 1 % and 0.5% respectively, regardless of the moisture content of the paddy. Therefore, it is desirable to breed rice varieties of the same physical properties as well as to improve a thresher adaptable to all the varieties. Torn heads, which increased with the moisture content of rall the varieties except the Milyang 23 , decreased as the cylinder speed increased, but grains with branchlet didnt decrease. The damaged kernels increased with the cylinder speed. 3. The thresher output quality was not affected much by the feed rate. But grains with branchlet and torn heads increased slightly with the feed rate for the head-feeding type thresher since higher resistance lowered at the cylinder speed. 4. In order to reduce grains with branchlet and torn heads in wet-paddy threshing , it is desirable to improve the head-feeding type thresher by developing a new type of cylinder which to not give excess impact on kernels or a concave which has differenct sizes of holes at different locations along the cylinder. 5. For the head-feeding type thresher, there was a difference in separating loss between the varieties. At the cylinder speed of 600 rpm the separating losses for the Minehikari and the Suweon 264 were 1.2% and 0.6% respectively. The separating loss of the head-feeding type thresher was not affected by the moisture content of paddy while that of the Mini-aged thresher increased with the moisture content. 6. From the analysis of the tailings return , to appeared that the tailings return mechanism didn't function properly because lots of single grains and rubbishes were unnecessarily returned. 7. Adding a vibrating sieve to the head-feeding type thresher could increase the efficiency of separation. Consequently , the tailing return mechanism would function properly since unnecessary return could be educed greatly. 8. The power required for the head-feeding type thresher was not affected by the moisture content of paddy, but the average power increased linearly with the feed rate. The power also increased with the cylinder speed.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.450-458
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• 2012

In order to reduce the effects of greenhouse gas (GHG) emissions, the South Korean government has announced a special platform of technologies as part of an effort to minimize global climate change. To further this effort, the Korean government has pledged to increase low-carbon and carbon neutral resources for biofuel derived from biomass to replace fossil and to decrease levels of carbon dioxide. In general, second generation biofuel produced form woody biomass is expected to be an effective avenue for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in road transport. It is important that under the new Korean initiative, pilot scale studies evolve practices to produce biomass-to-liquid (BTL) fuel. This study reports the quality characteristics of F-T(Fischer-Tropsch) diesel for production of BTL fuel. Synthetic F-Tdiesel fuel can be used in automotive diesel engines, pure or blended with automotive diesel, due to its similar physical properties to diesel. F-T diesel fuel was synthesized by Fischer-Tropsch (F-T) process with syngas($H_2$/CO), Fe basedcatalyst in low temperature condition($240^{\circ}C$). Synthetic F-T diesel with diesel compositions after distillation process is consisted of $C_{12}{\sim}C_{23+}$ mixture as a kerosine, diesel compositions of n-paraffin and iso-paraffin compounds. Synthetic F-T diesel investigated a very high cetane number, low aromatic composition and sulfur free level compared to automotive diesel. Synthetic F-T diesel also show The wear scar of synthetic F-T diesel show poor lubricity due to low content of sulfur and aromatic compounds compared to automotive diesel.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.2
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• pp.126-135
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• 1987

The physical properties, coliform groups, and nutrients were investigated to evaluate the sanitary Quality of the environmental water at Chinju area from May to October, 1986. The results were as follows : The pH ranged from 5.4 to 7.8 : water temperature ranged from 12.0 to $30.3^{\circ}C$ : electrical conductivity ranged from $0.51\times10^2\;to\;8.095\times10^2\mu\mho/cm$; chloride ion ranged from 3.6 to 126.8 mg/l, respectively. Especially, the concentration of the chloride ion at St.9 was 109mg/l which was higher than those of others. The $NO_3^--N$ ranged from 0.2336 to 14.1648 mg/l and the mean value was 5.4774 mg/l, the concentration of $NO_3^--N$ at St. 2 was higher as 40 times than that of St.4. The $PO_4^{3-}-P$ ranged from 0.0013 to 0.8315 mg/l, and the mean value was 0.0745 mg/l, the concentration of$PO_4^{3-}-P$ at St.8 was higher than that of others. The $SiO_2-Si$ ranged 1.7 to 15.28 mg/1 and the mean value was 5.81 mg/l. The value of St.8 and St.9 were higher than those of other stations but this value were lower $10\~13\;mg/l$ than the criterion for drinking water as 50 mg/l. The bacterial density of the spring waters ranged 9.1 to 4,600/100 ml (geometric mean : 205/100 ml) for total coliform 0 to 4s0/100 ml and 28.2/100 ml for fecal coliform. Composition of coliform was $38.2\%$ Escherichia coli, $25\%$ Entrobacter aerogenes, $13.2\%$ Citrobecter freundii and the others.

• Journal of Nutrition and Health
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• v.44 no.3
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• pp.231-242
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• 2011

The objective of this study was to investigate the effects of nutrition education based on ubiquitous healthcare (u-health) service on changes in dietary habits, nutrition intake, and risk factors for metabolic syndrome in male workers. In total, 72 male office workers with at least three risk factors of the National Cholesterol Education Program-Adult Treatment Panel III were recruited as subjects. Anthropometric measurements and biochemical analyses were conducted on all subjects. Dietary habits and nutrient intake were determined by a questionnaire using the 24-hour dietary recall method before and after nutrition education. Subjects measured their body composition, blood pressure, and physical activity more than once per week during the 12 weeks using the u-health care equipment and sent these data to a central database system using a personal computer. Individual nutrition counseling was provided four times on the first, fourth, eight, and twelfth weeks. The results showed significant decreases in abdominal circumference, body fat (%), diastolic blood pressure, serum triglycerides, and serum total cholesterol during the 12 weeks. Subjects with more than 12 measurements showed significant reductions in abdominal circumference, body fat (%), serum triglyceride, and serum total cholesterol. Mean intake of dietary fiber, animal calcium, potassium, vitamin C, and folic acid after nutrition education were higher than those before nutrition education. Participants showed significant increases in the frequencies of consuming protein foods (meat, fish, eggs, beans, tofu, etc.) and vegetables. In conclusion, nutrition education through the u-health service resulted in positive effects on the risk factors for metabolic syndrome, nutrient intake, and dietary habits.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.338-346
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• 2017

Natural seaweed beds and habitat environments were investigated using quantitative and qualitative methods from May to December 2015 at 3 sites in Gangneung, Uljin, and Busan along the eastern coast of Korea. In total, 9 green, 23 brown, and 64 red algal taxa were identified. The biomass of the seaweed at Gangneung was 173.2 to $613.8wet\;wt.g/m^2$ of Dictyota divaricata, 360.8 to $520.4wet\;wt.g/m^2$ of Symphyocladia linearis, and 25.9 to $470.8wet\;wt.g/m^2$ of Undaria pinnatifida. At Uljin, these numbers were 5.5 to $256.2wet\;wt.g/m^2$ of Plocamium telfarirae and 46.8 to $241.5wet\;wt.g/m^2$ of Agarum clathratum. The biomass of Sargassum coreanum and Ecklonia cava were 388.1 to $6,972.4wet\;wt.g/m^2$ and 194.9 to $958.5wet\;wt.g/m^2$, respectively, at Busan. S. coreanum and E. cava showed higher biomass compared to other seaweed at Busan. The biomass rate represented an average of 19.2 percent of the total population, ranging from 0.0 to 55.5 percent in Gangneung. In Uljin, the average was calculated as 63.8 percent, and this figure was 48.5 percent in Busan. The percentage of barren ground averaged 46.7 percent in Gangneung and 91.1 percent in Uljin. Uljin showed the highest percentage of barren ground compared to other regions. Sea urchin density appeared to be $6.0ind./m^2$ in Gangneung, $7.0ind./m^2$ in Uljin, and $2.0ind./m^2$ in Busan, with the lowest sea urchin density being that of Busan. In conclusion, the composition of species, appearance ratio, and abundance of vegetation found were similar to previous studies, but it is thought that continuous monitoring is needed due to concerns about physical and chemical pollution caused by global warming, climate change, and coastal development.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.5
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• pp.51-62
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• 2012

Geumho-dong, Seoul, a redeveloped residential area, is located in the foothills of Mt. Eungbong. The geographical undulation, the composition of a large apartment complex, and the partial implementation of the redevelopment project have caused the severe physical and social disconnections in this area. In order to recover functioning in the disconnected community, this study pays attention to the regeneration of the open spaces as an everyday place and in the form a network system among those open spaces. Various types of the open spaces are classified into points or faces, 'bases' and linear 'paths' analyze the network status. More than half of the open space have connecting-distance of 500m or more. Furthermore, many areas are not even included in the service-area of the open spaces. Analysis of the connectivity and integration value using the axial map has carried out to check weak linkages and to choose the sections where additional bases are required. In addition, to improve the quality of the bases and the paths, a field investigation is conducted and problems are diagnosed. The network planning of the open spaces in Geumho-dong is established, ensuring the quality and quantity of bases and paths. The plan includes the construction of an additional major base in the central area and six secondary bases in other parts, and comes up with ways to improve the environment of underdeveloped secondary bases. In the neighborhood parks at Mt. Daehyun areas, the major path are added, and the environment of the paths is improved in certain areas. Because of the network planning, the connecting-distances between bases are reduced significantly, the connectivity and integration value of the area are increased, and the service areas of the open spaces cover the whole area properly. Although this study has some limitations such as the needs for the legal and institutional supports and difficulties of a quantitative indexing process, its significance lies in the suggestion of a more reasonable and practical plan for the overall network system by defining complex types of open spaces simply and clearly and by examining the organic relationships quantitatively and qualitatively.