• Korean Journal of Ecology and Environment
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• v.33 no.1 s.89
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• pp.51-60
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• 2000

In order to understand the trend and assessment of water pollution, seasonal water quality was determined in the main river and the tributaries from midstream to downstream of the Kum River from March 1998 to June 1999. Among environmental factors, the variation of nitrogen, phosphorus and chlorophyll-a was distinctive on an aspect of increase and decrease relatively to others, and particularly the impact of inorganic N ${\cdot}$ P inflowing into the main river was observed to be more significant at the Kapchon, Mihochon and Soksongchon among the tributaries. Water quality was highly related to hydrologic factor, and it was more deteriorated when water discharge maintains for a long time below normal flow or relatively at low condition of minimum and drought flow. These phenomena were remarkablee from December to March of the next year. $NH_4$ and SRP were decreased dramatically flowing toward the lower part of the river and chl-a was increased exponentially. While, the variations of $NO_3$ and $BOD_5$ were regular from midstream to downstream and there was no significant difference between the stations. Limiting nutrient for Phytoplankton growth seemed to be P than N because the ratio of TN/TP or DIN/SRP was relatively high as 42 or 544 in the main river, respectively. The main river and tributaries were ranked to be third grade, based on the assessment of BOD as an indirect indicator of organics, but particularly Kapchon was ranked to be over fifth grade. In addition, the inflow of high N ${\cdot}$ P nutrients from tributaries including Kapchon and Mihochon seemed to be major factor of the development of water pollution of the Kum River. On the other hand, persistent bloom of phytoplankton in lower part of the river was observed. As a conclusion, management of water quality for main source of pollution is urgent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.351-360
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• 2016

The purpose of this study is to predict visual-spatial working memory performance through the characteristics of an electroencephalogram (EEG) in the resting state. The 31 study participants, middle school students with various to academic performance, were underwent visual-spatial working memory test in the Comprehensive Attention Test (CAT) on December in 2014. Each 7 and 6 participants were divided into an Excellent Working Memory (EWM) group and Poor Working Memory (PWM) group depending on the forward/backward working memory scores. The EEG measurements and analysis of the data from a Brain Function Tester were performed by the two groups. A Mann-Whitney Test was used to examine the statistical differences between them. The activation of high beta (${\beta}H$) at the Fp1 and Fp2 sites in the left and right hemisphere, and that of the low beta (${\beta}L$) in the right hemisphere in the EWM group was significantly higher than that in the PWM group. In conclusion, there is a correlation between the visual-spatial working memory performance and the activation of ${\beta}H$ and ${\beta}L$ in the resting state and a close correlation that of ${\beta}L$ in the right hemisphere in terms of mental activity and faculty. Therefore, the visual-spatial working memory performance can be predicted by the activation of ${\beta}H$ and ${\beta}L$ in the resting state. The activation of EEG can be applied as an assessment tool and provide basis data for visual-spatial working memory performance.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.818-831
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• 2008

The purpose of this study was to investigate the dietary behavior, health-related lifestyles and nutrient intake status of college students according to physical activity levels. The physical activity levels were measured using the Korean version of the International Physical Activity Questionnaire (IPAQ) short form. The subjects of this study were 438 college students (243 males and 195 females) in Incheon area and were divided by gender and by physical activity levels, which included low, moderate and high physical activity groups. The average age of male and female students were 23.7 and 21.0 years old, respectively. The prevalence of the low physical activity group was 11.5% for males and 30.8% for females and that of the high physical activity group was 38.7% for males and 22.6% for females. According to the criteria for obesity in Asia-Pacific region, 39.1% of the males and 64.1% of the female students investigated were in the normal range of BMI and 30.9% of the males and 4.6% of the female students were in the obesity category. However, percent of body fat in the female students was significantly higher than that of the male students. The soft lean mass of the high physical activity group was higher compared to the other groups. In the low physical activity group, frequency of “eating out” was lower compared to the other groups. The average consumption of energy was 74.4% for males and 80.1% for females of the estimated energy requirement (EER). The mean intakes of vitamin C, vitamin B2, folic acid and Ca were 67.3%, 84%, 52.7% and 36.7% for males and 64.8%, 99.9%, 51.1% and 40.1% for females of recommended intake (RI), respectively. Therefore, it was necessary for obesity prevention as well as health promotion to increase physical activity and to eat an adequate, balanced diet in female college students.

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.367-375
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• 2011

This study was carried out to investigate the effects of the level of cracked whole barley on daily feed intake, daily body weight gain, carcass characteristics and meat composition of finishing Hanwoo steers (feeding from 24 months to 30 months of age). The dietary treatments were consisted of five types (C; normal concentrate as a basal diet, T1; 10% addition of cracked whole barley, T2; 20% addition of cracked whole barley, T3; 30% addition of cracked whole barley, T4; 40% addition of cracked whole barley). A total 30 Hanwoo steers (588.6${\pm}$11.8kg) were allocated to 5 feeding groups. The daily feed intake and daily body weight gain were high in the order of T2 > T3 >T4 > T1 > C. The back fat thickness and longissmus muscle area were highest in C and T1, respectively (P<0.05) than other treatments. The meat yield index decreased with increased back fat thickness. The marbling score and meat quality were highest in T1 (P<0.01, 0.05, respectively), but maturity, fat color and meat color were not significantly different among treatments. The crude fat was highest in T1 (17.59%), while in T4 (7.47%) it was lowest (P<0.05). The crude protein and crude ash were not significantly different among treatments. The energy value of cracked whole barley treatments (T1, T2, T3, T4) was higher than C (P<0.05). The contents of Ca, Cu, K, Mg, Mo, Na and Zn were higher in C than the other treatments (P<0.01), but Co was higher in T2 (P<0.01). The CIE $L^*$ value of whole cracked barley treatments (T1, T2, T3, T4) was higher than C, however there were not differences among the treatments. The CIE $a^*$ value was highest in T1(P<0.05) than others. The CIE $b^*$ value was highest in C and it was decreased with increased feeding of cracked whole barley. Based on the above results, T1 treatment compared to other treatments improved the carcass quality parameters like loin muscle area, marbling score, meat quality, and CIE $L^*$ value.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.329-334
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• 2004

The objective of this study was to determine the effect of herb and bio ceramic complex supplementation on growth performance and meat quality characteristics in finishing pigs. Seventy-two crossbred (Landrace ${\times}$ Yorkshire ${\times}$ Duroc) pigs (78.98kg average initial body weight) were used in a 45 days growth assay. Dietary treatments included 1) Control (basal diet). 2) HBC (Herb and bioceramic complex) 0.1 (basal diet + 0.1％ Herb and bioceramic complex) and 3) HBC 0.2 (basal diet +0.2％ Herb and bioceramic complex). For overall period, ADG (Average Daily weight Gain), ADFI (Average Daily feed Intake) and ADG/ADFI increased in Control with no significant difference (p>0.05). Backfat thickness was not significantly different among the treatments (p>0.05). The total cholesterol, HDL (High Density Lipoprotein) cholesterol, LDL (Low Density Lipoprotein) cholesterol, LDL + VLDL (Very Low Density Lipoprotein) cholesterol, Triglyceride and Atherogenic index concentrations of serum in pigs fed HBC 0.2 diet were lower than those of pigs fed Control and HBC 0.1 diets without significant difference (p>0.05). L$\^$*/-, a$\^$*/-, and b$\^$*/- values of M. longissimus dorsi muscle were not significantly different among the treatments (p>0.05). The pH of pigs fed HBC 0.2 diet was significantly lower than that of pigs fed Control and HBC 0.1 diets (p<0.05). In conclusion, growth performance, cholesterol concentration in serum and meat quality were not affected by supplemental herb and bioceramic complex.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.3
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• pp.138-147
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• 2007

An emergy concept was used to evaluate the environment and economy of the Han River basin in Korea and to suggest policy perspectives far the sustainable utilization of its environment and associated estuarine ecosystem. The economy of the basin used $5.19{\times}10^{23}\;sej/yr$ of emergy in 2005. The economy of the Han River basin was heavily dependent on outside energy sources from foreign countries and other parts of Korea, with internal sources, renewable and nonrenewable, contributing only 15.6% to the total emergy use. The basin's trade balance in terms of emergy showed trade surplus, whereas there was a deficit in monetary terms. The population of the Han River basin was far greater than the carrying capacity calculated using the emergy flow, with renewable carrying capacity only at 1.8% of the basin's population and developed carrying capacity at 14.3%. The economy of the basin imposed a substantial stress on its environment, with an environmental loading ratio of 54.8. Overall, the economy of the Han River basin was not sustainable with an emergy sustainability of 0.02. These are reflected in lower quality of living expressed in the emergy term than the national average. Deconcentration of population and economic activities is needed to reduce environmental stress on the environment of the basin and its valuable estuarine ecosystem. Policies to restore ecosystem productivity of the basin are also needed to ensure the sustainability of the basin's economic activities and the sustainable utilization of the Han River estuary. In this regard, it is urgently needed for the Korean government to implement sustainable management measures for the Han River estuary, a well-preserved, productive natural estuarine ecosystem in Korea.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.222-231
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• 2005

Most of the tailings have been left without any management in abandoned metalliferous mines and have become the main source of heavy metal contamination of agricultural soils and crops in the these areas. To compare of environmental assessment of heavy metals in tailings derived from various 25-metalliferous mines in Korea, 3 different analysis methods such as water soluble, 0.1 M-HCl extractable, and total acid digestion method (aqua regia) were used. The chemical composition of water soluble in mine tailing were in the order ${SO_4}^{2-}>Ca^{2+}>Mn^{2+},\;Na^+,\;Al^{3+}>Mg^{2+},\;Fe^{3+}>Cl^-$. Specially, pH, EC, ${SO_4}^{2-},\;and\;Ca^{2+}$ concentrations in tailing varied considerably among the different mines. The average total concentrations of Cd, Cu, Pb, Zn, and As in tailing were 31.8, 708, 4,961, 2,275 and 3,235 mg/kg, respectively. Specially, the contents of Cd, Zn and As were higher than those of countermeasure values for soil contamination (Cd : 4, Zn : 700 and As : 15 mg/kg in soil) by Soil Environmental Conservation Act in Korea. The rates of water soluble heavy metals to total contents in tailings were in the order Cd > Zn > Cu > Pb > As. The rates of 0.1M-HCl extractable Cd, Cu, Pb, Zn, and As (1M-HCl) to total content were 17.4, 10.2, 6.5, 6.8 and 11.4% respectively. The enrichment factor of heavy metals in tailings were in the order As > Pb > Cd > Cu > Zn. The pollution index in tailing Au-Ag mine tailing were higher than those of other mine tailing. As a results of enrichment factor and pollution index for heavy metal contaminations in mine tailing of metalliferous mines, the main contaminants are mine waste materials including tailings.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.701-707
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• 2008

Antidiabetic effect of Korean red ginseng (RG) processed by puffing in streptozotocin (STZ)-induced diabetic (DM) rats was investigated. Five week-old SD rats were divided into four groups; normal control (NC) group, DM group, red ginseng (RG) group and puffed red ginseng (PG) group. The RG and PG groups were orally provided with RG or PG dissolved in water (500 mg/kg) respectively for seven weeks after single injection of STZ (50 mg/kg, i.v.) followed by identification of DM. NC group received saline vehicle instead of STZ. At the end of feeding of RG or PG, the changes of fasting blood glucose, serum insulin and amylase level and serum lipid profiles were evaluated. Also, oral glucose tolerance test (OGTT), comet assay and histopathological examination were performed. At 7th week, the fasting blood glucose levels of the RG and PG groups were reduced compared to the DM group by 11.54% and 20.22%, respectively. The result of OGTT did not show significant differences among DM and two red ginseng groups. While serum insulin and TG levels were predominantly improved in PG group (p<0.05), serum amylase level was increased in RG group. Alkaline comet assay for checking the oxidative damage of DNA showed that TL (tail length, ${\mu}m$) and TM (tail moment) in the blood lymphocyte of PG group significantly decreased in contrast with DM group. Histopathological results of pancreas showed that destruction of exocrine as well as endocrine might be cured by the administration of RG and PG. These results suggest that PG could exert more protection against STZ-induced toxicity than RG group.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.2
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• pp.139-155
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• 2009

Objective : To assess the biological stability of immediate transmucosal placement of tapered implants into tooth extraction sockets. Material and methods : Following tooth extraction, tapered implants were immediately placed into the sockets. Teeth with evidence of acute periapical pathology were excluded. After implant placement, sutured allowing a non-submerged, transmucosal healing. Standardized radiographs were obtained every visiting from baseline to 32 weeks after implant placment. Changes in depth of the distance from the implant shoulder (IS) and from the alveolar crest (AC) to the bottom of the defect (BD) were assessed. Results : Thirteen patients (10 males and 3 females) were enrolled and followed. They contributed with 15 tapered implants. extraction iste displayed sufficient residual bone volume to allow primary stability of all implants. The mean surgery time was $41{\pm}10.0$ mins. All implants healed uneventfully yielding a survival rate of 100%. Mean ISQ values were relatively stable. Interproximal crestal bone decreased $1.69{\pm}1.2mm$ (mesial), $1.65{\pm}1.2mm$ (distal) from baseline to 32-week follow-up. No statistically significant changes with respect to FMPS, FMBS, PPD and width of KG were observed. Conclusions: Immediate transmucosal implant placement represented a predictable treatment option for the replacement of teeth lost due to reasons including fractures, endodontic failures and caries.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.3-36
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• 2015

As of end of 2014, the population engaging in aviation activities for leisure has reached approximately 13 million, where approximately 356 cases involve a general aircraft, 200 cases involve light aircraft, and 636 cases involve an ULM. The industry for leisure has become a very promising industry in line with rapidly rising living standards which are expected to further increase in the future. The demand for such services is expected to increase over time. The purpose of this paper is to review the development and site selection of airfields in anticipation of these developments in the industry. While the government also has experience in the review of airfield location and candidate sites, it is not the government that carries out the actual construction. As such, the feasibility of the site needs to be verified in terms of actual construction. This study identified factors for Site Selection of factors through a review of related documents and existing research reports. A questionnaire was also used to collect the views of experts in the field, which was then analyzed. The Research model was confirmed in the layered form for an AHP analysis. The factors for Site Selection were identified as the technical / operational factors and economic / political elements for a two-stage configuration. The third step consisted of technical and operational elements. The final step is was constructed a total of 11 elements (weather, surface conditions, obstacle limitation surface, airspace conditions, operating procedures, noise problems, environmental issues, availability of facilities, construction and investment costs, contribution to the local economy, accessibility, demand / the proximity of demand). The surveys are conducted for more than 10 General and light aircraft pilots, professionals, and instructor. The analysis results showed a higher level in the technical / operating elements (73.2%) in the first step, while the next step sawa higher level of the operational elements (30.9%) than the other. The factors for Site Selection were any particular elements did not appear high, the weather conditions (17.5%), noise problems (19.8%), the proximity of demand (6%), accessibility (5.7%), environmental issues (11.1%), availability of facilities (8%), airspace conditions (7.9%), obstacle limitation surface (12%), construction and investment costs (4.2%) and to operating procedures (4.9%), contribution to the local economy (3.8%).