• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.110-118
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• 2006

The Namyang Stream in Hwaong polder was planned for several water uses including recreation, where people can contact the water and consume some amount during the recreational activity. A human health risk was assessed from exposure to E. coli in the Namyang Stream, which receives partially treated wastewater from watershed. The QUAL2E model was applied to simulate stream water quality, and this model was calibrated and verified with field monitoring data. The calibration result showed a high correlation coefficient of greater than 0.9. The mean concentration of E. coli in the Namyang Stream from the QUAL2E output was in the range of 5,000 ${\sim}$ 8,000 MPN 100 mL^{-1}$, which exceeded national and international guidelines. The Beta-Poisson was used to estimate the microbial risk of pathogens ingestion and the Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. The Microbial risk assessment showed that the risk ranged from 7.9 ${\times}\;10^{-6}\;to\;9.4\;{\times}10^{-6}$. Based on USEPA guidelines, the range of $10^{-6}\;to\;10^{-8}$ was considered reasonable levels of risk for communicable disease transmission from environmental exposure, and the risk above $10^{-4}$ was considered to be in the danger of infection. Therefore, water quality of the Namyang Stream might not be in the danger of infection although it exceeded national and international guidelines. However, it was in the range of communicable disease transmission, and thorough wastewater collection and treatment at the source is recommended to secure safe recreation water quality.

• 대한공업교육학회지
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• v.32 no.1
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• pp.134-152
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• 2007

This study deals with the development of computer program which can restrict students to access to the unallowable web sites during the Internet based class. Our suggested program can find the student's access list to the unallowable sites, display it on the teacher's computer screen. Through the limitation of the student's access, teacher can enhance the efficiency of class and fulfill his educational purpose for the class. The use of our results leads to the effective and safe utilization of the Internet as the teaching tools in the class. Meanwhile, the typical method is to turn off the LAN (Local Area Network) power in order to limit the student's access to the unallowable web sites. Our program has been developed on the Linux operating systems in the small network environment. The program includes following five functions: the translation function to change the domain name into the IP(Internet Protocol) address, the search function to find the active students' computers, the packet snoop to capture the ongoing packets and investigate their contents, the comparison function to compare the captured packet contents with the predefined access restriction IP address list, and the restriction function to limit the network access when the destination IP address is equal to the IP address in the access restriction list. Our program can capture all passing packets through the computer laboratory in real time and exactly. In addition, it provides teacher's computer screen with the all relation information of students' access to the unallowable sites. Thus, teacher can limit the student's unallowable access immediately. The proposed program can be applied to the small network of the elementary, junior and senior high school. Our research results make a contribution toward the effective class management and the efficient computer laboratory management. The related researches provides teacher with the packet observation and the access limitation for only one host, but our suggested program provides teacher with those for all active hosts.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.67-78
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• 2007

This study was carried out to monitor feed-nutritional components, toxic heavy metals (Cd, Pb and As) and pesticide residues through three cultivation stages (1st initial culture stage, 2nd mycelial growth stage, and 3rd fruit body-harvested stage) of king oyster mushroom (Pleurotus eryngii) produced by bottle type cultivation and oyster mushroom (Pleurotus osteratus) produced by vinyl bag type cultivation. For both cultivation types, compared with the initial culture, the weight reduction rate in spent mushroom substrates (SMS) after fruit body harvest was 29% for total wet mass, 21～25% for dry and organic matters and 19 ～22% for neutral detergent fiber. Two thirds to 3/4 of organic matter degraded and utilized by mycelia and fruit bodies was originated from fiber, of which the primary source (50～70%) was hemicellulose. The effect of mycelial growth stage on chemical compositional change in culture was little (P>0.05) for bottle type cultivation of king oyster mushroom but considerable (P<0.05) for vinyl type cultivation of oyster mushroom. Culture nutrients uptake by fruit bodies was very active for the bottle type cultivation. Compared with SMS, harvested fruit bodies (mushrooms) contained higher (P<0.05) crude protein, non-fibrous carbohydrate, and crude ash and lower (P<0.05) neutral detergent fiber. Regardless of stages, no culture samples were contaminated with toxic heavy metals and pesticide residues. In conclusion, the increase of fiber (neutral and acid detergent fibers) and indigestible protein contents and the decrease of true protein content in SMS indicated that the feed-nutritional value of SMS was significantly reduced compared with that of the initial culture and they were safe from toxic heavy metals and pesticide residues.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.298-310
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• 2007

This study compared the correlation between the accumulated copper content in earthworms and the copper concentration rate of soil measured using several methods to extract heavy metals from soil. For the experiment, a microcosm soil test was carried out using copper contaminated soil from the vicinity of copper-roofed buildings and earthworms (Eisenia fetida). Soils from the study area were used to produce 6 treatments; control, 1C (contamination level with the lowest treated copper concentration rate), 2C, 4C, 8C, and 16C (contamination level with the highest treated copper concentration rate). Microcosm soil test using the 6 treatments proved that as the copper content in soil and the experiment time increased, the growth rate of and the accumulated copper concentration rate in earthworms increased as well. The degree of the increase corresponded to the order of the treated copper concentration levels in microcosm soils. Standard method of the ministry of environment and EPA method 3051 were used to obtain the copper concentration in soil and the total copper content in soil, respectively. The correlation coefficient (r) of 0.9875~0.9993 between the copper content extracted by the standard method and the total copper content shows high positive correlation. The correlation coefficient of the copper content in soil extracted by the standard method and the accumulated copper content in earthworms, and the correlation coefficient of the total copper content in soil and the accumulated copper content in earthworms were ranged from 0.9193 to 0.9728 and from 0.9282 to 0.9844, respectively, showing highly significant positive correlation. Due to the high correlation between the copper concentration in soil and the accumulated copper content in earthworms, it is concluded that earthworms are suitable to be used as biological indicator species or for bio-monitoring against copper contamination of soil.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.52-68
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• 2014

In this study, we investigated the seasonal variation of SST(Sea Surface Temperature) and thermal effluents estimated by using Landsat-7 ETM+ around the Kori Nuclear Power Plant for 10 years(2000~2010). Also, we analyzed the direction and range of thermal effluents dispersion by the tidal current and tide. The results are as follows, First, we figured out the algorithm to estimate SST through the linear regression analysis of Landsat DN(Digital Number) and NOAA SST. And then, the SST was verified by compared with the in situ measurement and NOAA SST. The determination coefficient is 0.97 and root mean square error is $1.05{\sim}1.24^{\circ}C$. Second, the SST distribution of Landsat-7 estimated by linear regression equation showed $12{\sim}13^{\circ}C$ in winter, $13{\sim}19^{\circ}C$ in spring, and $24{\sim}29^{\circ}C$ and $16{\sim}24^{\circ}C$ in summer and fall. The difference of between SST and thermal effluents temperature is $6{\sim}8^{\circ}C$ except for the summer season. The difference of SST is up to $2^{\circ}C$ in August. There is hardly any dispersion of thermal effluents in August. When it comes to the spread range of thermal effluents, the rise range of more than $1^{\circ}C$ in the sea surface temperature showed up to 7.56km from east to west and 8.43km from north to south. The maximum spread area was $11.65km^2$. It is expected that the findings of this study will be used as the foundational data for marine environment monitoring on the area around the nuclear power plant.

• Journal of Environmental Policy
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• v.6 no.1
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• pp.41-60
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• 2007

Attempts were made to define the elements of debates, impact of decisions of the Access to Genetic Resources and Benefit-sharing(ABS) of the Conference of the Parties(COP) to the Convention on Biological Diversity(CBD) In Korea. Providing policy suggestions to cope with ABS, a cross-cutting issue of the meetings of the COP, was also undertaken. Meetings concerning ABS deal with several key matters such as an international regime, which is a legally binding implementation tool of the Bonn Guidelines, an international certificate of genetic resources' origin/source/legal provenance, and disclosure of origin of genetic resources, compliance measures with prior informed consent of the Contracting Parties providing such resources and with mutually agreed terms on which access was granted. Developing countries, rich in biodiversity and genetic resources, use the CBD as a major tool to maximize their national profits. They demand for national sovereign rights for the genetic resources and indigenous communities providing associated traditional knowledge. At the meetings of the COP, in addition, they requested that developed countries should transfer technologies and provide a financial mechanism for resource conservation to them. On the contrary, the developed countries argue that facilitating access to genetic resources is essential for scientific research and development, and that both Intellectual Property Rights and biotechnology using genetic resources should be protected to maximize their national benefits. Decisions of the COP concerning the Bonn Guidelines and compliance measures with ABS will affect on various socioeconomic fields of Korea, a country which is short of genetic resources. Especially, the importation of genetic resources and land development which might damage genetic resources will be limited seriously. Consequently, overall expenses will increase for the securing genetic resources from the foreign countries and developing biotechnology for conservation and sustainable uses of genetic resources. To minimize the adverse impacts, we endeavor to establish our clear standpoint and to lead the international trends, which are favorable for us. In order to achieve these objectives, government needs i) to proceed researches to lead the international ABS debates actively and to prepare the expected decisions of the future meetings of the COP, ii) to establish a national implementation plan to cope with the ABS and its related decisions, iii) to examine and improve the efficiencies of the national implementation plan with a proper monitoring system, and iv) cope with the other international meetings including the meetings of Trade Related Intellectual Properly Rights and International Treaty on Plant Genetic Resources for Food and Agriculture actively.

• Korean Journal of Ecology and Environment
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• v.47 no.2
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• pp.116-126
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• 2014

To evaluate the relationship between dynamics of Cyanobacterial bloom and rainfalls, a monthly monitoring of water quality and phytoplankton from the three serial lakes (Lake Ui-am, Lake Chung-pyeong and Lake Pal-dang) in the North Han River System were examined 12 times from May 2012 to March 2013. A dense bloom of cyanobacterium Anabaena spp., was occurred over three lakes in the summer season of 2012. In Lake Ui-am, the Anabaena population appeared in June, showed a peak in July (43,850 cells $mL^{-1}$) and disappeared in November 2012. In Lake Chung-pyeong and Lake Pal-dang, Anabaena population commonly appeared in July, showed the peaks (31,648 cells $mL^{-1}$ and 7,136 cells $mL^{-1}$, respectively) in August, and entirely disappeared in September 2012. Over the three lakes, the phytoplankton community was commonly dominated by diatoms before Monsoon, cyanobacteria during Monsoon, and diatoms after Monsoon, respectively, indicating a Monsoon-dependent succession. A correlation analysis revealed that dynamics of Anabaena population was strongly related with rainfall (r=0.72, r=0.83, r=0.88, P<0.01 for three lakes), and partly with nutrients, inflow and outflow of lakes. Therefore, this study indicates that the outbreak and destruction of Anabaena bloom in North Han River System between 2012 and 2013 was impacted by rainfalls. However, a high density of cyanobacteria in Lake Ui-am remained after Monsoon, and thus, may paroduce bad-order and toxins from phytoplankton.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.1-8
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• 2009

This study was conducted to investigate the effect of rainfall, irrigation and fertilizer application on water qualities of pond in golf course from May in 2007 year to November in 2008 year. For survey of water quality, it was sampled at $10{\sim}12$ sites(irrigation site 2, drainage site 3, and hazard site $5{\sim}7$) of SKY72 G.C and evaluated with analysis items such as pH, electrical conductivity(EC), DO, SS, T-N, $PO_4$-P, K, Ca, Mg, Na, SAR, BOD and COD. Results obtained were summarized as follows: The value of pH, EC, DO, T-N, P04-P, K, Ca, Mg, Na and SAR was in dry season, but those of SS, BOD and COD in the rainy season. N and P concentration of pond water showed $1.2{\sim}28.8mg/L$ and $0.005{\sim}0.172mg/L$, respectively, and so it was higher than eutrophication level of lakes and marshes recommended by the Ministry of Environment in Korea. As a reault of correlation analysis, EC in the water was significantly(P<0.01) related items such as K, Ca, Mg, Na, SAR and salinity, and SS significantly(P<0.05) BOD and COD. In comparison with a corelation between respective analysis items and rainfall amount, SAR was significantly(P<0.01) positive but T-N negative(P<0.01). As compared with corelation between respective items and irrigation amount, pH was significantly(P<0.01) positive but T-N(P<0.05) and BOD(P<0.01) negative. When it was applied to N, $P_2O_5$ and $K_2O$ in golf course, N and $K_2O$ significantly affected water qualities of pond(P<0.01). These results suggested that a pond water in golf course was affected by the fertilizer application, rainfall and irrigation and EC was adequate monitoring indicator for the evaluating water quality of pond by chemicals influent.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.4
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• pp.197-206
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• 2014

The purpose of this study is to evaluate coastal erosion due to a sea-level rise. The shoreline retreat rate was calculated due to future sea-level rise. Shoreline retreat rates were quantified with the cross-sectional data of 23 sandy coasts (12 sites from east coast, 5 sites from south coast, and 6 sites of west coast) and 3 cross-sectional profiles from each side of the coasts in Korea. The theory of equilibrium beach profile was employed in this study to evaluate the applicability of the theory into the coast of Korea and was tested with 15 cross-sectional beach profiles. Four scenarios of future sea level rise such as 38 cm, 59 cm, 75 cm, and 100 cm were adopted to estimate the shoreline retreat rates. Overall shoreline retreat rates for the coasts in Korea were predicted as 43.7% for 38 cm, 60.3% for 59 cm, 69.2% for 75 cm, and 80.1% for 100 cm sea level rises, respectively. Retreat rates in the east coast (29.6% for 38 cm, 45.1% for 59 cm, 56.0% for 75 cm, and 69.9% for 100 cm) showed relatively low compared to the south coast (51.9%, 67.6%, 77.2%, 87.3%) and the west coast (53.8%, 71.0%, 78.5%, 86.4%). However, all sandy coasts in Korea were assessed to be vulnerable with increasing sea-level rise. There are uncertainties in the assessment of this study, which include the limitation of the assessment model and the lack of the spatio-temporal data of the beach profiles. Therefore, this study shows that it is very important to spend integrated efforts to respond coastal erosion including comprehensive observations(monitoring) and the development of scientific understanding on the field.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.517-524
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• 2014

As an assessment of substantial equivalence and environmental risks of branchless chrysanthemum GM lines (LeLS69, LeLS76, LeLS80) developed in Korea, we investigated their degree of branchlessness and developmental characteristics including growth and flowering, as well as the stability of populations of insect pests and soil microbes. The GM lines were compared with a control variety, 'Jinba'. LeLS80 showed the highest level of branchlessness among the three GM lines, whereas abnormal axillary buds developed in lines LeLS76 and LeLS69. There were no significant differences between the growth characteristics of 'Jinba' and the GM lines. The branchlessness LeLS80 was increased during the summer season, suggesting that it is a useful germplasm for developing elite branchless cultivars. These GM lines showed no significant differences in the occurrence of five insect pests including aphids, mites, leaf miners, thrips, and whiteflies. Similarly, for soil microbes including bacteria and actinomycetes, there were no significant differences between 'Jinba' and the GM lines. However, there was a higher occurrence of fungi in the GM lines compared to 'Jinba'. Our findings suggest that 'Jinba' and the GM lines are substantially equivalent, although further monitoring studies are needed to confirm this.