• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.411-427
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• 2006

This study aimed to recognize characteristics of groundwater flow in fractured bedrocks based on zonal pump-ing tests, slug tests, water quality logs and borehole TV camera logs conducted on two boreholes (NJ-11 and SJ-8) in the city of Naju. Especially, the zonal pumping tests using sin91e Packer were executed to reveal groundwater flow characteristics in the fractured bedrocks with depth. On borehole NJ-11, the zonal pumping tests resulted in a flow dimension of 1.6 with a packer depth of 56.9 meters. It also resulted in lower flow dimensions as moving to shallower packer depths, reaching a flow dimension of 1 at a 24 meter packer depth. This fact indicates that uniform permissive fractures take place in deeper zones at the borehole. On borehole SJ-8, a flow dimension of 1.7 was determined at the deepest packer level (50 m). Next, a dimension of 1.8 was obtained at 32 meters of packer depth, and lastly a dimension of 1.4 at 19 meters of packer depth. The variation of flow dimension with different packer depths is interpreted by the variability of permissive fractures with depth. Zonal pumping tests led to the utilization of the Moench (1984) dual-porosity model because hydraulic characteristics in the test holes were most suitable to the fractured bedrocks. Water quality logs displayed a tendency to increase geothermal temperature, to increase pH and to decrease dissolved oxygen. In addition, there was an increasing tendency towards electrical conductance and a decreasing tendency towards dissolved oxygen at most fracture zones.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.1-20
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• 2004

This study focuses on the hydrochemical characteristics in goundwater affected by reclamation at 2000 Sydney Olympic Games site, Sydney, Australia. The Olympic Games site can be divided into three areas, i.e. reclaimed areas; landfill areas and non-infilled areas. In the current work, 'reclaimed areas' were previously estuarine, and were filled with waste materials and are now above present high tide level, whereas 'landfill areas' are areas where deposition of waste materials occurred above sea level. No deposition of waste took place in 'non-infilled areas'. This study was also evaluated by three different types such as deep boreholes, shallow boreholes and standpipes. The hydrochemishy of groundwaters in reclaimed and non-in-filled areas is characterized by Mg- and Ca-enrichment, whereas groundwaters in landfill areas are elevated in K and NO₃. Na, K and Mg are the dominant cations in groundwater from reclaimed areas and Na and K are the dominant cations in groundwater in landfill areas. Na and Mg are the dominant cations in groundwater in deep boreholes, whereas Na and K are the dominant cations in groundwater in shallow boreholes and standpipes. There is no distinct trend in heavy metals with electrical conductivity in the groundwater between the re-claimed, landfill and non-infilled areas. Fe and Mn in landfill areas with respect to reclaimed areas and non-infilled areas show a distinct increase in concentration with declining pH. Mean electrical conductivity values in the deep and shallow boreholes are higher than that of standpipes, but the minimum and maximum value of electrical conductivity in groundwater in standpipes shows remarkably different value, probably due to perched pond. There is no correlation between Cu, Pb, Zn, Cr concentrations in groundwater with pH, from deep boreholes, shallow boreholes and standpipes, except for Fe and Mn, which demonstrate increasing concentrations with declining pH. The results revealed a close association between elevated concentrations in groundwater and the presence of fill materials at the site. Trace metals teachability from re-claimed soils adjacent to estuary plays a significant role in determining their potential environmental risk to surrounding environment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.666-672
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• 1997

Twenty years' daily mean air temperature data was used to calculate the critical early seeding date(CESD), the optimum heading date(OHD), the critical late heading date for stable ripening(CHDR) and the critical late ripening date(CLRD) for rice seeded on dry paddy in different agroclimatic zones in Korea. The CESD was defined as the first day with mean air temperature of 13$^{\circ}C$, and the OHD as the first day of the 40 consecutive days with mean air temperature of 22$^{\circ}C$ or above after heading. The CHDR was defined as the date after which the cumulative daily mean air temperature would be at least 76$0^{\circ}C$. Lastly, the CLRD was defined as the last day when daily mean air temperature remains above 15$^{\circ}C$. This information was used for the estimation of periods from the earliest date of seeding to optimum heading date, the latest possible date of heading and the latest possible date of ripening in respective regions. For instance, in Suwon, those respective periods mentioned were found to be 104days, 124days, and 165days.

• Development and Reproduction
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• v.10 no.4
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• pp.227-238
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• 2006

Genomic DNAs(gDNAs) were isolated from the venus clam(Gomphina aequilatera) from Samcheok(venus clam from Samcheok; VCS) and Wonsan(venus clam from Wonsan; VCW) located in the East Sea of the Korean Peninsula. The amplified products were generated by agarose gel electrophoresis(AGE) with oligonucleotides primer, detected by staining with ethidium bromide and viewed by ultraviolet ray. The seven arbitrarily selected primers BION-21, BION-23, BION-25, BION-27, BION-29, BION-31 and BION-33 generated the shared loci, polymorphic, and specific loci, with the molecular sizes ranging from 150 bp to 2,400 bp. In this study, 147 polymorphic loci(147/954 loci, 15.41%) in VCS population and 274(274/996 loci, 27.51%) in VCW population were generated with seven primers. These results suggest the genetic variation in VCW population is higher than in VCS population. Especially, the 700 bp bands generated by the primer BION-21 were identified commonly in two Gomphina populations, which identified populations and/or species. This specific primer was found to be useful in the identification of individuals and/or population, resulting from the different DNA polymorphism among individuals/species/population. Two Gomphina populations between the individual SAMCHEOK no. 03 and WONSAN no. 22 showed the longest genetic distance(0.696) in comparison with other individuals used. The complete linkage cluster analysis indicating three genetic groupings and dendrogram revealed close relationships among individual identities within two geographical populations of venus clam(G. aequilatera) from the Samcheok and Wonsan. The intra-species classification and clustering analyses inferred from molecular markers supported the traditional taxonomy of the species based on morphological characters such as shell size, shape and color. Accordingly, as mentioned above, RAPD analysis showed that VCS population was more or less separated from VCW population.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.491-498
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• 2009

We studied to develop high-efficiency removal system of odor and VOCs(Volatile Organic Compounds) from environmental infrastructure facilities and oil refineries, painting facilities and so on. It can replace RTO and RCO. We tried an removal experiment for VOCs (toluene, xylene, benzene, MEK(methyl ethyl ketone), ethanol, formalin etc. and odor compounds (hydrogen sulfide, etc.). In process, as pre-treatment we used the scrubber with vortex flow (Multi-scrone) to remove the hydrophilic VOCs and as post-treatment, used fibrous bio-filter to remove the hydrophobic VOCs. This hybrid system remove with high efficiency both the hydrophilic VOCs and hydrophobic VOCs. And we tried to make this system to be compact. In experiment using Multi-scrone, contact time is 2~3 seconds and absorption scrubbing water is diaphragm-type electrolysis water. hydrophilic VOCs like ethanol and relatively hydrophilic odor compounds like hydrogen sulfide is excellent, these substances has been removed almost completely, respectively 95~99%, 93~97%. And for MEK, formalin also Showed a high removal efficiency, respectively 78~90%, 72~85%. But in experiment using Multi-scrone, the hydrophobic VOCs like BTX showed a low removal efficiency, respectively 16~22%, 12~18%, 8~16%. In hydrophobic VOCs, toluene removal experiment using fibrous bio-filter, early efficiency was low but after 10days, adaptation period showed high efficiency 85~95%. but in the mixed phase, toluene and MEK efficiency reduced 5~10%. this show microorganism treat first MEK easy to remove. The removal efficiency for MEK using the fibrous biofilter was stable, 80~92%. This hybrid system is also high economical efficiency for RTO. This system reduce more than 50% the cost of equipment and maintenance. As a result, we expect this technology is in the limelight as high efficiency treatment of VOCs in mid-low price.

• Economic and Environmental Geology
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• v.47 no.6
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• pp.611-623
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• 2014

The alluvial aquifer, widely developed near the four major rivers such as Nakdong River, can be used effectively for groundwater artificial recharge and is expected to be the future water resources in Korea. This study is aimed at examining the impact of repeatedly injected river water into the riverside alluvial aquifer on injection rate or efficiency in its system at Changweon area. For this, injection tests were performed two times, first on June 19 and second on September 25 through October 9, 2013, and the mixing ratios of river water to groundwater were used as the tool to compare the efficiency of injection. The mixing ratios were evaluated by using electrical conductivities of injected river water (average $EC=303{\mu}S/cm$) and groundwater ($EC{\fallingdotseq}6,000{\mu}S/cm$) measured at 20 m depth of four observation wells installed 10 m apart from each injection well. The result shows the remarkable differences on two respects. First, in some observation well, detection time for incipient injection effect during $2^{nd}$ injection test was shown to be much slower than that of $1^{st}$ injection test. Second, the hourly increasing rate of mixing ratios in $2^{nd}$ test was revealed to be reduced much more than that of $1^{st}$ test. This means that the efficiency of injection was badly deteriorated by only 1,210 minute injection work. Therefore, injection water needs to be adequately treated beforehand and repeated pumping work and/or resting phase is needed afterwards. To a certain extent, the improvement of water quality in saline aquifer was verified in this system by injection tests.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.394-398
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• 1997

Changes of nutrient material and heavy metals of irrigation water and natural supplies by irrigation water into 1.0ha of paddy field during the rice cultivation was investigated pH of irrigation water ranged 6.458.34 and electrical conductivity showed $110{\mu}S/cm$ in the first irrigation period and commonly showed $90{\mu}S/cm$. The content of T-N, NH4-N and $NO_3-N$were 3.09~12.36, 0.17~1.34 and 2.70~10.72mg/L respectively. The content of T-P was 0.09~0.22mg/L and ortho-P was not detected. The content of $Ca^{++},\;Mg^{++},\;Na^+\;and\;K^+$ showed 0.89~5.12, 1.12~2.76, 1.74~4.52 and 1.34~4.18mg/L regardless of irrigation season respectively. Only Cu and Zn of heavy metals were detected 0.001~0.009 and 0.007~0.091mg/L, but Pb, Cd, Cr and Ni were not detected When supplied $4,250m^3$ of an irrigation water into 1.0㏊ of paddy field, natural supplies of nutrient materials were 29.67㎏ of T-N, 1.80㎏ of $NH_4-N$, 24.57kg of NO3-N and 0.51kg of T-P. Also $Ca^{++},\;Mg^{++},\;Na^+,\;K^+,\;Cl^-\;and\;SO_4\;^{2-}$ were supplied 9.42, 7.09, 13.34, 9.08, 40.27 and 41.38kg respectively. Only Cu and Zn of heavy metals were supplied 0.017kg of Cu and 0.133kg of Zn, Pb, Cd, Cr and Ni were not supplied

• Korean Journal of Environmental Agriculture
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• v.34 no.1
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• pp.38-45
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• 2015

BACKGROUND: For commercial production of greenhouse crops under shorter day length condition, supplementary radiation has been usually achieved by the artificial light source with higher electric consumption such as high-pressure sodium, metal halide, or incandescent lamps. Light-Emitting Diodes (LEDs) with several characteristics, however, have been considered as a novel light source for plant production. Effects of supplementary lighting provided by the artificial light sources on growth of Kale seedlings during shorter day length were discussed in this experiment. METHODS AND RESULTS: Kale seedlings were grown under greenhouse under the three wave lamps (3 W), sodium lamps (Na), and red LEDs (peak at 630 nm) during six months, and leaf growth was observed at intervals of about 30 days after light exposure for 6 hours per day at sunrise and sunset. Photosynthetic photon flux (PPF) of supplementary red LEDs on the plant canopy was maintained at 0.1 (RL), 0.6 (RM), and $1.2(RH){\mu}mol/m^2/s$ PPF. PPF in 3 W and Na treatments was measured at $12{\mu}mol/m^2/s$. Natural light (NL) was considered as a control. Leaf fresh weight of the seedlings was more than 100% increased under the 3 W, Na and RH treatment compared to natural light considering as a conventional condition. Sugar synthesis in Kale leaves was significantly promoted by the RM or RH treatment. Leaf yield per $3.3m^2$ exposed by red LEDs of $1.2{\mu}mol/m^2/s$ PPF was 9% and 16% greater than in 3W or Na with a higher PPF, respectively. CONCLUSION: Growth of the leafy Kale seedlings were significantly affected by the supplementary radiation provided by three wave lamp, sodium lamp, and red LEDs with different light intensities during the shorter day length under greenhouse conditions. From this study, it was suggested that the leaf growth and secondary metabolism of Kale seedlings can be controlled by supplementary radiation using red LEDs of $1.2{\mu}mol/m^2/s$ PPF as well as three wave or sodium lamps in the experiment.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.66-72
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• 2009

Diabetic Retinopathy (DR) is a leading cause of blindness among adults in the western countries. Hyperglycemia is a condition, that induces apoptotic cell death in a variety of cell types in diabetes, but the mechanism remains unclear. The aim of the study is to understand the effects of high Glucose on Human Retinal Endothelial Cells. Retinal endothelial cells were cultured in Iscove's Modified Dulbecco's Medium (IMDM) containing 5, 25 and 50 mM Glucose, incubated for 24, 36 and 48 hours in humidified 5 % CO$_2$ incubator at 37$^{\circ}C$. Human Retinal Endothelial Cell Line (HREC) were characterized for morphology with different treatment by phase contrast microscopic analysis. Number of dead and viable cells was counted by trypan blue exclusion and supported by MTT assay. The intracellular Hydrogen peroxide (H$_2$O$_2$), a Reactive Oxygen Species (ROS) generation in high glucose conditions was assessed by FOX II assay and apoptosis by caspase-3 assay. The high glucose treated cells undergoing DNA fragmentation was witnessed by Agarose gel electrophoresis. We found that the cells incubated with 25 and 50 mM glucose containing medium for 48 hours altered the morphology of the cell, induced apoptosis and DNA fragmentation. The dead cell number were high in 25 and 50 mM when compared to the cells incubated with 5 mM glucose for 24, 36, and 48 hours. Also, the H$_2$O$_2$ levels and the activity of caspase-3 were increased in high glucose treated cells. Conclusions/interpretation: Our results demonstrated that elevated glucose induces apoptosis in cultured HREC. The hyperglycemia-induced increase in apoptosis may be dependent on caspase activation. The association between ROS generation and caspase-3 activation on high glucose treated cells is yet to be investigated.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.183-192
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• 2002

The present studies were carried out to examine the effects of exogenous oxytocin(OT) on plasma, uterine and placenta of estradiol-17$\beta$, progesterone, prostaglandin F$_2$$_{\alpha}$ (PGF$_2$$_{\alpha}$), Prostaglandin E$_2$(PGE$_2$) and OT receptor concentrations in pregnant rats. Pregnant rats received an injection of exogenous OT on days 14, 16, 18, 20, 22 of pregnancy and day 1 of postpartum. Concentrations of plasma estradiol-17 $\beta$ after OT injection started to increase after day 18 and peaked on day 22 of pregnancy but decreased on day 1 of postpartum. Plasma progesterone concentrations declined gradually from day 18 of pregnancy and decreased more rapidly until postpartum 1 day. Concentrations of estradiol-17$\beta$in uterine tissues after OT injection were sharply increased from day 20 to 22 of pregnancy and progestrone concentrations were peaked on day 16 and decreased rapidly from day 16 to 20 and maintained the same level until day 1 of postpartum. Uterine concentrations of PGF$_2$$_{\alpha}$ and PGE$_2$increased gradually until day 20 and peaked on day 22 of pregnancy but showed a marked decrease on day 1 of postpartum. Concentrations of PGF$_2$$_{\alpha}$ in placental tissues increased rapidly from day 14 of pregnancy and decreased sharply on day 1 of postpartum. Concentrations of PGE$_2$increased gradually after day 14 and peaked on day 20 of pregnancy. The concentration of OT receptor in uterus was significantly elevated from day 20 and rose to maximum on day 22 of pregnancy. These findings show that OT suppress the concentration of progestrone and stimulate productions of estradiol-17 $\beta$, PGF$_2$$_{\alpha}$, PGE$_2$ and oxytocin receptor concentrations in pregnant rats.