• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.37-44
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• 2013

This study was to investigate water quality and biotic community characteristics in Juam Lake. In water quality, water temperatures was $3.8{\sim}21.2^{\circ}C$, 6.7~8.6 in pH, $64{\sim}76{\mu}s\;cm^{-1}$ in Conductivity, $5.3{\sim}13.2mg\;L^{-1}$ in DO, $2.5{\sim}3.3mg\;L^{-1}$ in COD, $1.0{\sim}5.1mg\;L^{-1}$ in SS, $0.622{\sim}0.841mg\;L^{-1}$ in T-N, $0.007{\sim}0.019mg\;L^{-1}$ in T-P and $2.8{\sim}8.8mg\;m^{-3}$ in Chl-a. Revised Carlson's Index (TSIm) assessment using total phosphorus (TP) and chlorophyll-a domonstrated that the trophic states of Juam Lake were rated as mesotrophic. A total of 53 species of phytoplankton were identified. They were 28 Bacillariophyceae, 13 Chlorophyceae, 3 Cyanophyceae, and 9 Other algal taxa. The standing crops of phytoplankton was ranged from $113cells\;mL^{-1}$ to $2,909cells\;mL^{-1}$. A total of 16 species of zooplankton were identified (10 rotifers, 4 cladocerans and 2 copepods). Total zooplankton abundance was $309ind.\;L^{-1}$ to $435ind.\;L^{-1}$. The collected benthic macroinvertebrates from the surveyed sites in Juam Lake were 1,038 individuals, 33 species, 21 families and 12 orders. A dominant species was Uracanthella rufa and a subdominant species was Ecdyonurus kibunensis. Hydrophytes recorded from Juam Lake were identified 9 taxa. Emerged plants, floating plants among the hydrophytes was classified 8, 1 taxa, respectively. Ecosystem disturbance wildplant by Environment Ministry found were Paspalum distichum var. distichum and Ambrosia artemisiaefolia. A total of 30 species (6 families) were collected fishs from Juam Lake. There were 10 Korean endemic species (33.3% of collected species number) and 3 exotic species (10.0%).

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.320-328
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• 2016

This study was conducted to provide important basic information about effective management of the marine environment at major inflow streams in Lake Andong and Lake Imha. The investigation was conducted 8 times from May, 2015 (AD1, AD2, IH1, IH2) to September, 2016 (AD3, AD4, IH3, IH4), and 8 surveyed sites were selected at Lake Andong (4 sites) and Lake Imha (4 sites). The inquiry identified 114 species, $59,913.7inds.\;m^{-2}$ in Lake Andong and 112 species, $39,038.4inds.\;m^{-2}$ in Lake Imha. The results indicate that the number of species and individuals in Lake Andong is more than that in Lake Imha, because Lake Andong has a variety of riparian vegetation and a richness of organic materials. Community analysis at Lake Imha revealed a dominant index of 0.57 (${\pm}0.18$), a diversity index of 2.87 (${\pm}0.31$), an evenness index of 0.73 (${\pm}0.04$), and a richness index of 4.17 (${\pm}0.71$). The results of functional feeding group analysis showed that a high proportion of species and individuals are gathering collectors. The results of functional habitat group analysis showed that a high proportion of species and individuals are clingers. The result of a physico-chemical water assay and dissolved oxygen and electric conductivity tests revealed that these measures increased when the water temperature decreased. The result of Pearson's correlation analysis by biological factors and physico-chemical factors showed that species and electric conductivity are highly correlated with one another. Major inflow streams of Lake Andong and Lake Imha were exposed to various point pollution sources and non-point pollution sources. This implies a necessity for continuous monitoring of the aquatic ecosystems in order to effect systematic water quality management of Lake Andong and Lake Imha.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.61-72
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• 2014

This paper analyzed transition pathways toward a low carbon society in Korea to meet global $2^{\circ}C$ climate target. Lower economic growth, industrial structure change, enhance of energy demand management, decarbonization of power sector, and replacement of low carbon fuel could reduce greenhouse gas (GHG) emission from fuel combustion in 2050 by 67% against in 2011, or by 74% against in BAU (Business-As-Usual). Lower economic growth contributes to 13% of cumulative emission reduction relative to BAU, industrial structure change 9%, enhance of energy demand management 72%, decarbonization of power sector 5% and replacement of low carbon fuel 1% respectively. Final energy consumption in 2050 needs to be reduced to 50% relative to 2011, or to 41% relative to BAU. Nuclear, coal and renewable energy represent 31%, 40%, 2% respectively among electricity generation in 2011, but 38%, 2%, 32% in 2050. CCS represents 23% of total generation in 2050. Emission intensity of electricity in 2050 was decreased to 19% relative to 2011, or to 24% relative to BAU. Primary energy in 2050 was decreased to 64% compared to 2011, or to 44% compared to BAU. Final energy consumption, primary energy supply and GHG emission from fuel combustion from 1990 to 2011 increased by 176%, 197%, 146%. Radical change from historical trend is required to transit toward a low carbon society by 2050. Appropriate economic growth, structural change to non-energy intensive industries, energy technology research, development and deployment (RD&D) in terms of enhancement of energy efficiency and low carbon energy supply technologies, and fuel change to electricity and renewable energy are key instruments.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.103-109
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• 2016

Polyethylene pipes has useful benefits which are anti-corrosive and flexible material, so it is used to gas pipes but also class 3 water pipes of nuclear power plant, process pipes of petrochemical plant and chemical plant. So the usage of polyethylene pipes is widely increased. But it has been limited for the usage of polyethylene, because it can not be directly detected to fusion joints by using non destructive evaluation. Polyethylene pipes are connected by two methods, one is butt fusion and the other is electrofusion. Butt fusion is widely used to connecting the pipes. It is proposed to method for determining the reliability of joints in this study that is detection of the melt flow zone at fusion joints. In this study, middle density polyethylene is used, outside diameter of the test specimen is 225mm and thickness is 20.5mm. Speed of ultrasonic of this test specimen is 2,200m/s. Test specimens were fabricated by varying the heating time which means from 0% to 130% applying time through heating plate to polyethylene for detecting melt flow zone. Also 4 additional test specimens were made, one was made that not scrapping attached surface of pipes but applying 100% of the proper heating time and the others were made to include of soil, gravel and vinly tape paper at fusion joints, that were also applied 100% of proper heating time. Ultrasonic testing to measure the melt flow zone of 20 test specimens was conducted by using 3.5MHz and 5.0MHz ultrasonic probes and melt flow zone measuring was conducted to three times at different point to one specimen. To differentiate the melt flow zone signal, post image processing was equally conducted to all test results and image levels, contrast, sharpen, threshold were adopted to all teat results and the test results were displayed gray scale. From the results, for the shorter heating times the reflection area of multiple echo have been increased, so the data was obtained from the position where it can be eliminated as much as possible. At 80% of proper heating time(168 sec.), the signal of melt flow zone was obtained clearly, so measuring could be conducted. From 7% of proper heating time(15 sec.) to shorter heating times. we could not obtain the signal because test specimen was not fused. From the result, we can verify that measuring of melt flow zone by using phased array ultrasonic imaging method is possible. And we can verify to complete and incomplete butt fusion by measuring the melt flow zone.

• Applied Microscopy
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• v.38 no.1
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• pp.11-19
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• 2008

To examine the effect of the electrolyzed alkaline reduced water (ERW) on animal immunity, by employing Echinostoma hortense that is a parasite in the small intestine, the immune response of C57BL/6 was examined. To C57BL/6 mice, Echinostoma hortense metacercaria 15 per animal was in oculate dorsally, the worm was collected after 2 weeks, and the change of goblet cells and mast cells in the mucosa of small intestine was examined, and by using a protein chip, the change of cytokines in the serum was compared and observed. As a result, average 8.3 worms were collected from the C57BL/6 mice infected with E. hortense, and in the group fed with the ERW, average 10 worms were collected. In regard to the examination of the change of goblet cells, in the experimental group infected with E. hortense and fed with the ERW, average 4.3 worms per villus were detected, hence, it was found that the expression of goblet cells was low (p<0.001). Regarding the examination of the change of mast cells, similarly, in the group infected with E. hortense and fed with the ERW, average 11 worms per villus were detected, and it appears to be less than control group (p<0.001). Regarding the expression of cytokines in mouse serum, in comparison of the experiment group infected with E. hortense and control group, in the expression of the Th1 cytokines IL-6, IL-$1{\beta}$, IFN-${\gamma}$, TNF-${\alpha}$, and IL-2, and the Th2 cytokines IL-4, IL-5, IL-10, and IL-13, a significant difference was not detected. In our study, it was found that in the infection of E. hortense, the ERW mediates its effect on the number of goblet cells and mast cells in the intestinal mucosa, and simultaneously, the worm expulsion was delayed, and thus the conclusion that the ERW mediated its effect on the intestinal immunity of mice was obtained.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.3
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• pp.45-76
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• 2000

The purposes of this study were to investigate and understand the present status of various types of "deserts", such as sand desert, gravel desert, rock desert, earth desert, salt desert, desert, rocky desert, gobi desert, sandy desert, clay desert, etc., and the general countermeasures for the combating "desertification" "desertization", and to develop the technologies on the revegetation and restoration for the combating desertification in China. The methods of this study were mainly composed of field surveys on the several experimental sites and research institutes related to combating desertification in China, and examinations on the various technologies for the combating desertification at the Daxing Experimental Station of Beijing Forestry University. The conclusion from this study may be summarized as follows; 1. Status and tendency of desertification in China : China is one of the countries seriously threatened by desertification. Desertification affected areas in China are mainly distributed in arid, semi-arid and dry sub-humid areas in China, covering the most regions of the Northeast China (eastern region of Inner-Mongolia), the northern part of the North China (middle and western region of Inner-Mongolia, Shaanxi, Ningsha, Gansu) and the western part of the Northwest China (Xinzang, Qinghai, Xizang). The total area affected by desertification in China is approximately 2.622 million $km^2$. It covers 27.3% of the total territory of China. Until recently, it is estimated that the annual spreading ratio of desertification in China is 2,460 $km^2$. Therefore, desertification is mostly serious problems facing to the Chinese people. 2. The causes and environmental effect of desertification : The desertification in China is mainly caused by compound factors, including natural condition and human activities. In China, the desertification is started by the decrease of precipitation, continuous dry and drought, strong wind, wind and water erosion, land degradation and loss of natural vegetation caused by climate variation, and accelerated by the human activities, such as over-cultivating, over-grazing, over-cutting of woods, irrational use of water resources. Because desertification has affected the geographical features, soil nutrients contents, salinity, vegetation coverage and the functions of ecosystem, the environmental deteriorations in the desertification affected areas are very seriously. 3. The fundamental strategies of combating desertification in China are the increase of education and awareness of people through various mass media, the revision of laws to guarantee operation of Desertification Combating Law and to improve many relating laws and regulations, the application of advanced technologies and training of experts, the establishment of discriminative policies, and increasing arrangement of budget-investment, and so on. China, as a signed country in UNCCD, has made efforts for the combating desertification. Korea is also signed country in UNCCD, so we should play an important role in the desertification combating projects of China for the northest asia and global environmental conservation as well as environmental conservation of Korea.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.67-72
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• 2003

This study was conducted to investigate the effect of germanium biotite on the growth performance, blood composition , fecal NH$_3$-N and volatile fatty acid(VFA) in broiler chicks. Two hundred forty broiler chicks were randomly allocated into five treatments with four replicates for five weeks. Dietary treatments included 1) Control, 2) GB1(basal diet + 200 mesh 0.5%), 3) GB2(basal diet + 325 mesh 0.5%), 4) GB3(basal diet + 200 mesh 1.0%) and 5) GB4(basal diet +325 nesh 1.0%) For overall period, weight gain, feed intake and feed conversion were not significantly different among treatments (P>0.05). Digestibilities of nutrients were not affected by adding GB(P>0.05). No differences occurred in red blood cell(RBC), white blood cell(WBC), hematocrit(HCT), hemoglobin(Hb), lymphocyte, monocyte and platelet of blood among the treatments (P>0.05). Fecal NH$_3$-N concentration of chicks fed GB1.0 diets(GB3 and GB4) was lower(P<0.03) than chicks fed GB0.5 diets(GB1 and GB2). Propionic acid and butyric acid in feces of chicks fed GB diets were lower(P<0.04) than in chicks fed control diet. GB diets reduced fecal acetic acid significantly compared to control (P<0.01). Also, acetic acid of feces in chicks fed GB1.0 diets(GB3 and GB4) was lower(P<0.02) than GB 0.5 diets(GB1 and GB2) treatments. In conclusion, dietary germanium biotite was an effective means of decreasing fecal NH$_3$-N and volatile fatty acid(VFA) emission.

• Korean Journal of Poultry Science
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• v.42 no.2
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• pp.139-145
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• 2015

The objective of this experiment was to investigate the effects of dietary supplementation of Lycii fructus (LF) and Glycyrrhiza uralensis (GU) mixture on growth performance, blood parameter, immune response and intestinal microflora in broiler. A total 750 1-d old ROSS 308 was randomly allotted to 1 of 3 dietary treatments with 5 replicates during d 35 of the feeding trial. Two additional diets were prepared by adding 0.5 or 1.0% of LF and GU mixture to the basal diet. The experimental diets were fed on an ad libitum basis to the birds during 35 d. Results indicated that increasing inclusion level of LF and GU mixture in diets improved BW gain (quadratic, P<0.05) and improved feed conversion ratio (quadratic, P<0.05) of birds during to 0 to 21 d. Increasing inclusion level of LF and GU mixture in diets improved BW gain (linear and quadratic, P<0.05) of birds during to 0 to 35 d. The leukocyte concentrations were not affected by increasing inclusion level of LF and GU mixture in diets. Plasma IgG concentration was increased (linear, P<0.05) as the concentrations of LF and GU mixture in diets increased. The concentrations of Lactobacillus spp. in the ileal content of birds increased (linear, P<0.05), but those of Escherichia coli decreased (quadratic, P<0.01). These results suggest that dietary LF and GU mixture may be used as a functional ingredient to improve growth performance, plasma IgG and intestinal health of birds.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.143-149
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• 2007

The experiment was conducted to examine the effects of dietary organic selenium and vitamin E on weight gain, feed intake, feed conversion, and selenium retention in meat of broiler chickens. For each growth phase, the basal diet was supplemented with 0 (control), vitamin E 150 IU/kg and the combination of 1.2 ppm Se from selenium yeast (SY) and vitamin E 100, 150, 200 and 300 IU/kg. Weight gain was significantly higher in supplemental control and vitamin E 150 compared to the combination of 1.2 ppm SY and vitamin E 150 IU during day 1 to 21. Feed intake significantly(P<0.05) increased in supplemental vitamin E 150 compared to the combination of 1.2 ppm SY and vitamin E 150 and 200 IU during day 1 to 21. Feed intake was significantly(P<0.05) higher in control compared to that of combination of 1.2 ppm SY and vitamin E 200 IU during day 21 to 35. However feed conversion was not affected in supplemental vitamin E and SY during day 1 to 35. Selenium concentrations of breast muscle and liver tissue significantly increased (P<0.05) in supplemental combination of 1.2 ppm SY and vitamin E compared to the control and vitamin E 150 IU. TBARS of control and vitamin E 150 IU were significantly (P<0.05) higher in day 3 than day 1, but the combination of Se 1.2 ppm and vitamin E of TBARS had no difference during day 1 to 3. TBARS in day 3 was significantly (P<0.05) lower in supplemental combination of Se 1.2 ppm and vitamin E than control and vitamin E 150 IU.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.105-110
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• 2007

This experiment was conducted to investigate the effects of stocking density on performance and blood characteristics of broiler chicken in summer. One day-old 648 male commercial broiler chicks(Ross strain) were divided into 3 groups with 4 replicates(12 pens), 41 to 69 birds per pen, to compare the stocking density difference on growth performance and blood characteristics. Birds in T1, T2 and T3 were reared in different size 0.050, 0.066, 0.083 $m^2$/bird floor, respectively. The birds were fed the same experimental diet ad libitum for 5 weeks. Chickens were weekly weighed and one bird was selected from each pen to measure blood characteristics at the end of experiment. Body weight and feed intake increased significantly in low density treatment(T3) compare to that of high density treatment(P<0.05). Feed conversion was significantly improved in customary treatment(T2) relative to that of other treatments(P<0.05). No significant difference was observed in moisture contents of bedding among treatments. In blood characteristics, low density treatment(T3) decreased the total protein, cholesterol and albumin, but were no significant difference. From the result of this study, it could be concluded that the higher stocking density might give more stress to the birds from physical stimuli and thus were harmful environment causing lower productions compared to the lower ones