• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.5
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• pp.110-120
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• 2009

The hipped roof on the research building, which was constructed 51.9m above sea level on a hillock by Korea National University of Education in June 1999, is composed of four inclined planes which are 12m in breadth, 8m in length and have a 30 degree gradient. For the roof vegetation, the yellow earth collected from around the building was laid on top. It was designed to supply the soil on the slope with water for a considerable period by making rainfall pool at the edges. In order to prevent the soil on the slope from being swept away, 31 sorts of grass seeds were imported from Germany and sown in the soil. At the present day, 10 years after the seeds began to sprout and inhabit the settled slope, 30 individual plant species were identified in the period between April 2008 and March 2009. Out of 31 species were seeded on the slanted, soiled roof, only 8 were still alive. It was confirmed that the Artemisia Princeps var, Chrysantheum, Prunella Vulgaris and Lespedeza Cuneata have been the major species inhabiting the east, west, south and north inclined planes respectively. The Phragmites Communis was inhabiting the edge of the roof where the water supply was adequate, while the Dianthus Barbatus was primarily inhabiting the south-east side of the roof. As a whole, 26 identifiable plants and 4 unidentified plants were observed on the inclined planes of the hipped roof. In consideration of the plant distribution on the slope, it was confirmed that the selection of seeds may have had an effect on the slope vegetation. As for the yellow earth laid on the roof, it was discovered that about 2~3cm thickness around the ridge was swept away, but the rest of the slope was in relatively good condition. Accordingly, it has been proven that vegetations can be applied to hipped roofs by using ordinary plants without any special structural measures.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.1-13
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• 1997

The fermentative conversion of food wastes into feed was investigated by seeding of mixed inoculum YM (Youngjin Environmental co.), and thermotolerant yeast Kl. marxianus. For 6 days' fermentaion, the fermentation method of 2 days' aerobic followed by 4 days' anaerobic was better for the production of organic acids and increasing total microbial population than 6 days' continuous aerobic or anaerobic fermentation. By seeding YM, the total microbial count increased about 100 times of the control group. In addition, Kl. marxianus seeding together with YM increased total viable cell count, but did not increase yeast count significantly.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.53-61
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• 1999

This study was conducted to determine the optimal collecting time and methods of utilization of forest topsoil as a seed-bank source for revegetation materials of slopes. From April to November of 1998, nursery seedbeds in the greenhouse of Seoul National University were seeded with mixtures of forest topsoil and seeds. The nursery seedbeds were treated to evaluate the effect of depths of forest topsoil and seeding amounts. Seasonal experiments with $3{\times}3$ factorial design were conducted in April, June and August. More than 40 seedlings/$m^2$ were observed as the naturally-emerged species in the plot, treated with the top-layer forest soil within the depth of 10cm. However, it was found, as seeding more seeds, the number of appearance of the naturally-emerged species reduced because of the heavy competition between the seeded and the naturally-emerged. According to the results of this research, it is recommended that seeding amount should be no more than 1,000 seeds/$m^2$ to avoid the severe competition. Also it was observed that the forest topsoil collected in spring(April) is better than that collected in summer. The more species of the naturally-emerged were found in the forest topsoil collected in spring. Forest-topsoil-mixed-materials as a seed-bank source could significantly increase the plant diversity and productivity. Effective use of forest topsoil as a seed-bank source may become a valuable tool in future restoration of disturbed slopes for promoting plant community diversity and recycling of spoiled-soils from the slopes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.62-69
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• 1999

This study was carried out to find out the capability of applying such materials as porous concrete, could be called environmentally friendly materials, for bringing vegetations. For verying the purpose of the experiments such materials as potland cement and slag cement, coarse aggravates(${\phi}25mm$, ${\phi}18mm$, ${\phi}13mm$) were mixed. In the voids of porous concrete peatmoss and chemical fertilizers were filled, and on the surface of concrete organic soils were adhered for seeding grasses. For testing compressive strength, pH, voids the 12($4mixed{\times}3times$) specimens were manufactured. As results, the compressive strength of porous concretes were from 59 to $267kg/cm^2$ depend on mixed ratios between cements and coarse aggregates. Voids of concrete were from 33% to 40% and the pH were varied pH 8-10.5. So the capability of planting vegetations was to be ascertained. The germination and growth of grasses were not good, but it could be found out that the capability of vegetations on the concretes. For generalizing these results and applying on the construction sites, it is necessary to verificate following studies for various conditions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.2
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• pp.15-22
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• 2022

This study has been conducted to investigate the appropriate mixed sowing rates with white clover (Trifolium repens) and Kentucky bluegrass (Poa pratensis) by evaluating initial growth. Six different mixed sowing rates (CT, Control Trifolium repens; CP, Control Poa pratensis; T1P3, Trifolium repens 1 : Poa pratensis 3; T1P2, Trifolium repens 1 : Poa pratensis 2; T1P1, Trifolium repens 1 : Poa pratensis 1; T2P1, Trifolium repens 2 : Poa pratensis 1; T3P1, Trifolium repens 3 : Poa pratensis 1) with three repetitions were implemented in greenhouse experiment plastic pots (50.5 length × 35.0 width × 8.5 cm height). Plant height, leaf length, leaf width, number of leaves, root length, fresh weight, and dry weight were measured after a week from the germination for three months. Initial growth of Kentucky bluegrass significantly increased as mixed sowing rates with increasing, while that of white clover kept relatively decreasing than that in Control. Initial growth strongly affected sowing mixed rates by Kentucky bluegrass and not by white clover in this experiment, indicating that grasses played a dominant role during initial growth period. However, seeding rates with white clover will be dependent on the use of a turf and the desired green cover. There remains a need to further study of the mechanisms and dynamics of legume and grass competition to underpin sustainable management practices.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.32-39
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• 2017

This study was carried out to investigate the ACCase inhibiting herbicide resistant Echinochloa oryzicola collected in a Honam rice field and to investigate the control of E. oryzicola in directly seeded paddy rice field. The study result showed that about 44% of the 67 biotypes collected in the rice field in Honam region were resistant to ACCase-inhibiting herbicides. The efficacy of several chemical herbicides on these resistant E. oryzicola biotypes was evaluated according to their application timings. Among herbicides applied 4 days before seeding, pretilachlor, butachlor, oxadiazon, oxadiargyl, oxadiazon+pretilachlor, and fentrazamide+oxadiargyl, provided 95% or higher control of the resistant E. oryzicola biotypes. Among the herbicides applied 10 days after seeding, bromobutide+fentrazamide+imazosulfuron, benzobicyclon+fentrazamide+imazosulfuron, pyrazosulfuron-ethyl+thiobencarb, fentrazamide+imazosulfuron, bromobutide+imazosulfuron+mefenacet and bromobutide+imazosulfuron+pyraclonil provided ${\geq}95%$ control of the weeds. Bromobutide+imazosulfuron+mefenacet and bromobutide+pyrazosulfuron-ethyl+pyriminobac-methyl, applied 15 days after seeding, provided ${\geq}95$ and 90% control of the weeds. Foliar application of cyhalofop-butyl+propanil at 30 days after seeding provided ${\geq}90%$ control of the weeds. In addition, oxaziclomefone provided ${\geq}90%$ control for 40 days after soil application. These results show that E. oryzicola biotypes resistant to ACCase-inhibiting herbicides could be effectively controlled in directly seeded rice in submerged paddy fields using single or tank-mixed chemical herbicides currently available on the market.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.112-127
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• 1997

The purpose of this study is to get optimum operating factors of Upflow Anaerobic Sludge Blanket (UASB) reactor by introducing methods that make it to reduce inhibition possible in each process wastewater treatment. The used substrates, concentrated corn starch liquid (CSL) wastewater, modified starch, filtering and decoloring wastewater, ion refining wastewater, and mixed wastewater including modified starch and not including modified starch, are generated from molasses process. The seeding sludge is the digested sludge that had been applied to molasses wastewater. Batch test to reduce the inhibition factors that might be existed in each wastewater was examined. Based on the this test, the optimum operating factors according to alkalinity and pH variation was studied through the continuous test using three 5.5 L UASB reactor. The first reactor added $NaHCO_3$ to control alkalinity. The hydraulic retention time (HRT) reduced to 8 hours and the organic loading rate increased gradually. The second reactor changed the pH of influent from 7.0 to 6.0 using NaOH. The third reactor was operated without changes to compare the above two reactors. As the result, the inhibition in concentrated CSL wastewater was removed by adding iron (II). When trace metals were added to mixed wastewater not including modified starch, the digestability by gas production rate increased to more fifty percentage than mixed wastewater that was not adding the trace metals. The reason that the inhibition did not decreased in spite of adding trace metals and nutrients was influenced by high concentration generated during the acid fermentation. The UASB reactors using the mixed wastewater with the most effective performance were operated as 500 mg/L as $CaCO_3$ alkalinity and 6.0 pH at steady state, and at this time, the gas production rates were 283 and 311mL gas/g $COD_{added}$. The COD removal rates were 84.7 and 86.3%, respectively.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.22-27
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• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.167-170
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• 1998

To apply diamond films in microelectromechanical systems(MEMS), it is necessary to develop the patterning technologies of diamond films in the micrometer scale. In this paper, three different kinds of technologies for patterning CVD diamond films carried out by us were demonstrated: selective growth by improved diamond nucleation in DC bias-enhanced microwave plasma chemical vapor deposition (MPCVD) system, selective growth of seeding using diamond-particle-mixed photoresist, and selective etching of oxygen ion beam using Al as the mask. It was show that high selectivity and precise patterns had been achieved, and all the processes were compatible with IC process.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.178-181
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• 2011

The test was carried out at a test field at the Wanju Eco-Farming Complex from 2009 to 2010 to figure out the proper application of fertilizers when growing rice at the Eco-Farming Complex. The result showed that when compared to the basal application of compost as fertilizer, applying supplementary compost after natural re-seeding of chinese milk vetch (CMV) helped balance soil nutrition and maintained rice yields.