• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.4
• /
• pp.283-288
• /
• 2013

To evaluate the ability of the submerged plant, Ceratophyllum demersum's (C. demersum) to remove nutrients and to inhibit growth of cyanobacteria, a total of 6 mesocosms were conducted in a batch reactor for 9 days. From the 84 hr of the experiment, C. demersum was stabilized and showed daily cycle trends according to changes in pH and DO levels. The concentration of nutrients, $NH_3{^+}$, $NO_3{^-}$ and $PO_4{^3}$ continuously decreased until 9 days of the experiment, with the rapid decrease in nutrient concentration for the first 24 hours. High correlation coefficient ($r^2{\geq}0.96$, p<0.001) between the amount of C. demersum's biomass per unit area and the nutrients removal level were derived, and greater C. demersum's biomass per unit area showed higher removal efficiency of nutrients. However, there were differences in the C. demersum's activity level between batch reactors with higher and similar density of the C. demersum, but nonetheless water purification effect appears to have a significant influence due to attached algae and microorganisms. The growth rate of harmful cyanobacteria, Microcystis aeruginosa (M. aeruginosa) with C. demersum's density of 2,500 g $fw/m^2$ (100% of cover degree) was 0.31 /day, compared to the growth rate of 0.47 /day for the control group (0% of cover degree). In terms of number of cells, the control group had 1.7 times higher number of cells than the experimental group, proving that C. demersum has the ability to inhibit the growth of harmful cyanobacteria.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.18 no.2
• /
• pp.94-101
• /
• 2015

To mitigate the greenhouse gas emission, many carbon capture and storage projects are underway all over the world. In Korea, many studies focus on the storage of $CO_2$ in the offshore sediment. Assurance of safety is one of the most important issues in the geological storage of $CO_2$. Especially, the assessment of possibility of leakage and amount of leaked $CO_2$ is very crucial to analyze the safety of marine geological storage of $CO_2$. In this study, the leakage of injected $CO_2$ through fault was numerically studied. TOUGH2-MP ECO2N was used to simulate the subsurface behavior of injected $CO_2$. The storage site was 150 m thick saline aquifer located 825 m under the continental shelf. It was assumed that $CO_2$ leak was happened through the fault located 1,000 m away from the injection well. The injected $CO_2$ could migrate through the aquifer by both pressure difference driven by injection and buoyancy force. The enough pressure differences made it possible the $CO_2$ to migrate to the bottom of the fault. The $CO_2$ could be leaked to seabed through the fault due to the buoyancy force. Prior to leakage of the injected $CO_2$, the formation water leaked to seabed. When $CO_2$ reached the seabed, leakage of formation water stopped but the same amount of sea water starts to flow into the underground as the amount of leaked $CO_2$. To analyze the effect of injection rate on the leakage behavior, the injection rate of $CO_2$ was varied as 0.5, 0.75, and $1MtCO_2/year$. The starting times of leakage at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 11.3, 15.6 and 23.2 years after the injection, respectively. The leakage of $CO_2$ to the seabed continued for a period time after the end of $CO_2$ injection. The ratios of total leaked $CO_2$ to total injected $CO_2$ at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 19.5%, 11.5% and 2.8%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.1
• /
• pp.63-69
• /
• 2015

This study was conducted to measure the effect of PE film mulching and irrigation methods on the growth, yield and antioxidant activity of potatoes tubers, in order to examine the possibility of cultivating potatoes in winter season in vinyl greenhouse on the reclaimed tidal land with weak ground inside the sea wall currently completed. The test was conducted on the sandy loam soil (Munpo series), and its salt concentration was 0.42% at the time of planting. The emergence speed per kind of PE film mulching was in the order of black > coloration > transparent > green color, with the black color showing the fastest speed. The temperature change during a day per kind of PE film mulching was in the order of transparent > coloration > green > black color. As for the salt concentration in the soil for each different way of water management, the salt concentration in the treatment of drip irrigation with 1 week interval was lower than that drip irrigation with 2 weeks interval. As for the growth of above-aerial part, plant length was higher, number of tiller and leaves were more and dry weight of above-aerial part was larger in the treatment of drip irrigaton with 1 week interval than drip irrigation with 2 weeks interval. As for the yield of potatoes depending on each way of water management, the yield in the treatment of drip irrigation with 1 week interval was more than drip irrigation with 2 weeks interval. The yield for each different kind of PE film mulching in the weekly drip-irrigation management section was in the order of transparent ${\geq}$ black ${\geq}$ coloration ${\geq}$ green color. In both of total phenol content and DPPH free radical activity experiments, the content and activity were higher with pear color vinyl treatment.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.3
• /
• pp.319-324
• /
• 2014

Soybean (Glycine max (L.) Merr.) is an important crop for protein, oil, carbohydrates, isoflavones, and many other nutrients to humans and animals. But, antinutritional factors in the raw mature soybean are exist. Raffinose and stachyose are main antinutritional factors in soybean seed. Both raffinose and stachyose are carbohydrates, belonging to the raffinose family of oligosaccharides (RFOs). RFOs are not readily digested in humans and cause flatulence or diarrhea. The objective of this research is to obtain the information on raffinose and stachyose content according to genotype and environment. A total of twenty two soybean genotypes (11 cultivars, 3 germplasms and 8 breeding lines) were selected. Each genotype was grown in the field for two years with two replications and harvested in bulk at natural maturity for two years. Content of raffinose and stachyose was detected by HPLC. The raffinose content (g/kg) of 22 genotypes was $2.68{\pm}0.21-5.87{\pm}2.43$ in year 1 and was $3.24{\pm}0.37-9.05{\pm}0.16$ in year 2. The stachyose content (g/kg) was $4.23{\pm}0.98-27.68{\pm}9.90$ at year 1 and was $5.11{\pm}1.09-25.32{\pm}0.35$ in year 2. Genotype and environment have highly significant effects on raffinose and stachyose content. Three genotypes (Da-7, 116-13, and RS-78) have low stachyose content at 5% significant level in two years. A positive correlation ($R^2=0.1985^*$) between raffinose and stachyose was observed in year 2. These informations are valuable in soybean genetics and breeding program related with raffinose and stachyose content.

• Development and Reproduction
• /
• v.13 no.4
• /
• pp.353-362
• /
• 2009

GnRH and its receptor are known to express locally in the ovary and to regulate the ovarian function by affecting on granulosa and lutein cells. It has been reported that GnRH directly causes apoptosis in the granulosa and lutein cells of the ovary. However, whether the apoptosis of the cells by GnRH is recovered by FSH as an anti-apoptotic factor is not yet known. In this study, we evaluated the apoptosis and the production of progesterone $(P_4)$ and estradiol $(E_2)$ after treatment with 5, 50, and 100 ng/$m\ell$ GnRH and 1 IU/ml FSH in the granulosa-lutein cells that are obtained during oocyte-retrieval for IVF-ET. Results of DNA fragment analysis and TUNEL assay demonstrated that DNA fragmentation and the rate of apoptotic cells were increased in a dose-dependent manner showing a significant increase in the cells treated with 100 ng/$m\ell$ GnRH. In addition, we found that FSH suppresses the apoptosis of the cells induced by GnRH. In the results of chemiluminescence assay for $P_4$ and $E_2$, $P_4$ production was decreased by GnRH treatment, whereas $E_2$ production was not changed. We also demonstrated that FSH inhibits the suppressive effect of GnRH on $P_4$ production as the result of apoptosis. The present results suggest that GnRH agonist using in ovarian hyperstimulation protocol might induce the dysfunction of the ovary, but its function could be recovered by FSH. These results also will be expected to use as the basic data to elucidate the physiological role of GnRH and to develop new ovarian hyperstimulation protocols for IVF-ET.

• Economic and Environmental Geology
• /
• v.41 no.1
• /
• pp.63-79
• /
• 2008

Physicochemical characteristics of stream water, leachate, mine water and groundwater were investigated to estimate the influences of the tailing and waste rock from the abandoned Uljin mine area. Total extraction analysis and mineralogical studies were carried out to understand sulfide weathering and to determine the distributions of trace elements in the soil affected by mine waste (tailing, waste rock and leachate). The pH and EC value of the leachate from the tailing disposal ranged 2.9-6.0, $99{\sim}3,990{\mu}S/cm$, respectively, and the concentrations of dissolved major (up to 492 mg/l Ca; 83.8 mg/l Mg; 45.2 mg/l Na; 44.7 mg/l K, 50.8 mg/l Si) and trace elements (up to $826,060{\mu}g/l$ Fe; $131,230{\mu}g/l$ Mn; $333,600{\mu}g/l$ Al; $61,340{\mu}g/l$ Zn; $2,530{\mu}g/l$ Cu; $573{\mu}g/l$ Cd; $476{\mu}g/l$ Pb) were relatively high. The stream water showed the variation of dissolved metal concentrations in seasonally and spatially. The dissolved metal contents of the stream water increased by influx the leachate from the tailing disposal, but these of the down stream have been considerably decreased by mixing of dilute tributaries. The dissolved metal concentrations of the stream water at dry season (as February) were lower than these at rainy season (as May and July). These represent that the amounts of the leachate varied with season. However, stream water could not be effectively diluted by confluence with uncontaminated tributaries, because the flux of tributaries and streams reduced at dry season. Thus attenuations by dilution had been dominantly happened in rainy seasons. The order of accumulations of trace element in soils compared with background values revealed Mn>Fe>Pb>Cu>Zn. Sulfide minerals were mainly pyrrhotite, sphalerite and galena and chalcopyrite. Pyrrhotite was rapidly weathered along the edge and fractures, and results in the formation of Fe-(oxy)hydroxides, which absorbed a little amount of Zn.

• Archives of design research
• /
• v.19 no.4 s.66
• /
• pp.51-60
• /
• 2006

Nowadays, reading text from screens is prevailing in everyday life. The advent of mobile information devices such as a cellular phone, PDA, and e-book reader facilitates us to enjoy various text-based contents any time and anywhere. Most studies comparing screen and paper readability show that screens are less readable than paper. Furthermore, the decrease of line length and number of lines that can be displayed on the screen of mobile information devices deteriorate text readability. This study investigated parameters affecting text readability on small screens and designed a new text layout to improve readability. We suggested a diagonally splitted layout of rectangular column, which is supposed to facilitate eye movement to trace text flow with ease. The experiment comparing readability between a traditional rectangular column and a diagonally splitted column was conducted. The result of experiment revealed that there is no significant difference between the two text layouts in terms of subjective satisfaction of reading task and a level of comprehension. However, in the screen size of $4000mm^2\;and\;8000mm^2$, reading speed was increased 18.9% and 34.0% respectively from a traditional rectangular column to a diagonally splitted column. We conducted a consecutive experiment to scrutinize the cause that improved the performance in readability task remarkably. The readability of text in a traditional rectangular column was compared with a left triangular column and a right triangular column in the condition of $4000mm^2/3:1$ ratio screen. The performance measurements revealed that participants read 21.1% and 67.6% faster respectively with the left triangular column and right triangular column than with the rectangular column. In consequence, the improvement of readability in the diagonally splitted column was attributed mainly to the increase of reading speed in the right triangular column. This research verified that the diagonally splitted column improve text readability on a small screen and this result is expected to make a contribution to designing an efficient text layout for mobile information devices

• Korean Journal of Environmental Agriculture
• /
• v.15 no.3
• /
• pp.372-382
• /
• 1996

In order to elucidate the relationship between the mobility of heavy metals in soil and their uptake by plants, the soil samples collected from the Mangyeong River area were analyzed for the contents and existing forms of the heavy metals and the correlation between the contents of heavy metals in the soil and those in various parts of rice plants therefrom. The soil samples were collectes from ten sites in the paddy fields in 1982 and 1990, respectively, and the analysis on heavy metals including Cd, Zn, Cu and Pb was performed. The results are as follows: Total contents of heavy metals in the samples of 1990 were higher than those of 1982. The extent of increase was that Cd, Zn, Cu and Pb were 3, 29, 59 and 8% in top soil and 8, 50, 91 and 8% in sub-soil, respectively. The order of increasing ratio was Cu > Zn > Pb > Cd and the variation of Cd content by sequentially different extraction was organically bound > dilute acid-extractable=Fe-Mn oxide bound > exchangeable > residual fractions and the content of Cd with organically bound was $46.62{\sim}48.08$ and $41.18{\sim}50.18%$ of total Cd in top and sub-soil, respectively. The ratios of immobile heavy metals, Cd, Pb, Cu and Zn, bound within an oxide or silicate matrix of Fe-Mn oxide in top-soil were 21.25, 35.98, 74.18 and 82.12%, respectively, and consequently their mobile ratios of exchangeable, dilute acid-extractable and organically bound were more than 17.88%. Those of mobile Cd, Pb, Cu and Zn were 78.25, 64.02, 25.82 and 17.88%, respectively. Except for Pb a correlation between the contents of Cd, Zn, and Cu of exchangeable and dilute acid-extractable in top-soil and those in leaf blade, stem and panicle axis was significant, but was not significant in sub-soil.

• Journal of Animal Science and Technology
• /
• v.47 no.4
• /
• pp.583-592
• /
• 2005

This experiment was conducted to determine the effects of dietary copper levels on performance, carcass characteristics, and economical analysis in Hanwoo steers. Fifteen Hanwoo steers weighing about 300kg were randomly allotted into one of three treatments. The three treatments consisted of Control(7mg Cu/kg feed), TI(12mg Cu/kg feed) and TII(17mg Cu/kg feed). Copper was formulated with concentrate from copper sulfate($CuSO_4$) and animals were fed the diets supplemented with copper from 300kg untill about 630 kg of body weight. Dietary copper levels did not affect daily weight gain, feed intake and feed efficiency during the whole feeding period. Dressing percentage, rib eye area and backfat thickness were not different between animals fed the diets supplemented with copper. Animals fed the diets supplemented with copper received the same B grade in yield grade. Animals fed the diets supplemented with copper received same marbling score. Beef color, fat color, texture and maturity were not affected by Cu supplementation in diet. Animals received the same first grade between treatments in quality grade. Animals fed the diet supplemented with 12mg of copper per kg diet was higher in profit by 13.3% than animals fed the control diet. According to these results, it may be concluded that performance, yield and quality grade were not affected by the Cu levels of 7 to 17mg per kg feed but crude income was enhanced when Hanwoo steers were fed the diet containing 12mg Cu/kg feed.

• Journal of Animal Science and Technology
• /
• v.47 no.4
• /
• pp.525-536
• /
• 2005

This study was carried out investigate the effect of replacing soybean meal with feather meal or Bacillus sp. inoculated feather meal in finisher pig diets on the performances, and amino acid composition and carcass characteristics of pork. One hundred fifty pigs were randomly allotted to five dietary treatments (① control, basal diet; ② BSM (bacillus sp. inoculated soybean meal) 10, 10% of soybean meal was replaced with bacillus sp. inoculated feather meal; ③ BSM 20, 20% of soybean meal was replaced with bacillus sp. inoculated feather meal; ④ CSM (conventional soybean meal) 10, 10% of soybean meal was replaced with conventional feather meal and ⑤ CSM 20, 20% of soybean meal was replaced with conventional feather meal) in a 70-days feeding trial. In overall period, body weight gain of BSM 20 (0.95kg) was higher (P<0.05) than those of CSM 10 (0.80kg) and CSM 20 (0.81kg), respectively. And feed conversion of BSM 20 (2.94) was lower (P<0.05) than that for other treatments (3.06-3.41). Carcass weight of BSM 10 (81.84kg) and BSM 20 (83.77kg) were greater (P<0.05) than those of CSM 10 (74.75kg) and CSM 20 (76.07kg), respectively. Proportion of grade A carcass in BSM 20 (35.03%) was higher compared to the control treatment (32.78%). CIE L* of meat color was lowest in the BSM 10 (45.56), and hightest (P<0.05) in the CSM 20 (59.96). In addition CIE a* of meat color of control (9.35) highest (P<0.05) than those of BSM 10 and BSM 20 were 7.56 and 7.42, respectively.