• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.93-98
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• 2008

We investigated the effect on the removal of BOD, SS, TN and TP and algal growth inhibition of Vegetated Artificial Floating Island (VAFI), by examining microorganism activity and nutrient uptake in the batch test of various conditions: (1) Blank (Control group), (2) VAFI of $0.25m^2$, (3) AFI of $0.25m^2$ which has no vegetation, (4) buoyant plate of $0.25m^2$, (5) buoyant plate of $0.25m^2$ with linear media. The proportion of BOD removal in the VAFI, AFI, buoyant plate and buoyant plate with media were 82.7, 80.8, 45.2% and 59.6% respectively. TN removal in the VAFI, AFI and buoyant plate with media were 51.2, 31.7% and 25.1% respectively. TP removal in the VAFI, AFI, buoyant plate and buoyant plate with media were 23.3, 16.7, 10.0% and 13.3% respectively. Chlorophyll-${\alpha}$ removal in the VAFI was 97.9%. The factors of chlorophyll-${\alpha}$ removal in the VAFI accounted for the shading effect of 35.1%, microorganisms activity of 61%, and plant root of 1.8%.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.280-291
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• 2011

Bottom-up approaches to control of Microcystis aeruginosa blooms were comparatively investigated through an in situ mesocosm experiment using aquatic plants (Iris pseudoacorus). In the mesocosm experiments, floating I. pseudoacorus, seemed to be effective in controlling massive M. aeruginosa blooms in an agricultural reservoir, exhibiting a close coupling with temporal variations in Chl-a and DO concentration. Shading by floating I. pseudoacorus resulted in a reduced phytoplankton abundance inhibiting light energy availability. Moreover, I. pseudoacorus may suppress phytoplankton growth through the excretion of chemical substances, likes a allelopathy, that inhibit phytoplankton photosynthetic activity. The $^{15}N$ atom % of I. pseudoacorus showed higher values than POM, suggesting that I. pseudoacorus assimilates DIN predominantly compared to phytoplankton, which was mostly M. aeruginosa. This result strongly suggests that the M. aeruginosa bloom should be regulated by aquatic plants, like I. pseudoacorus, this approach can affect zooplankton composition. This is the first study that has used stable isotope tracers to evaluate the biomanipulation efficiency through floating I. pseudoacorus.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.4
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• pp.295-304
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• 2000

Vertical measurement of CTDT at about 30 min intervals and spatial surface temperature, salinity, and concentration of suspended particulate matters were conducted to elucidate the character of water column and the dispersal pattern in a floating ice-dominated fjord, Marian Cove, West Antarctica. Marian Cove showed two distinct water layers in terms of turbidity; 1) cold, fresh, and turbid surface plume in the upper 2 m,2) warm, saline, and relatively clean Maxwell Bay inflow between 15-45 m in water depth. Thermal melting of Maxwell Bay inflow and tidewater glacier/floating ices developed the surface mixed layer and the activity of floating ices cause Maxwell Bay inflow to be unstable. Due to the unstable water column, the development of Maxwell Bay inflow and subsequent surface plume are not influenced by tidal frequency. Coastal current generated by strong northwesterly wind may extend warm, saline, and turbid surface plume into the central part of the cove along the northern coast via the western coast of Weaver Peninsula. Terrigenous sediments of meltwaters from the glaciated ice cliffs near the corner of tidewater glacier and some coasts enter into the cove and their dispersion depends upon the hydrographic regimes (tide, wind, wave etc.). At the period of spring tide, the strong wind stress with the northwesterly wind direction reserve suspended sediment-fed surface plume and so allow the possibility of deposition of terrigenous sediments within the basin of cove.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.226-233
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• 1988

Some physico-chemical properties and biological activities of new fungicide formulations were tested to investigate a feasibility of water-floating formulation development for sheath blight control in rice. Pencycuron[1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] and flutolanil$({\alpha},{\alpha},{\alpha}$-trifluoro-3'-isopropoxy-O-toluanilide) were chosen as toxicants for the formulations. Vegetable oil and surface active agents were used as a floating agent and spreader, respectively. All the formulations tested showed an excellent spreadability on the water having over $35cm^2/mg$ and were chemically stable, which the degradation rates of active ingredients were less than 10% after 12 weeks of storage at $50^{\circ}C$. Most of the applied test formulation of pencycuron was retained within 0.5cm of the surface paddy water, while that of flutolanil was vertically dispersed in the water. Inhibition activity of the tested pencycuron formulation on the sclerotia germination of the pathogen in paddy water was maintained over 30 days after the formulation treatment. Control effect of 4% pencycuron water-floating formulated with surface active agent of hydro-lipophyllic balance 4.3 on the disease in rice was equal to the reference fungicide(pencycuron 25% WP) when the former was treated one day before the transplantation of rice seedlings. Overflowing the submerged paddy water after the formulation treatment resulted in a deterious effect on the disease control.

• Journal of the Korean Chemical Society
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• v.62 no.3
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• pp.226-234
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• 2018

In this study, the models described in the textbooks related to floating and sinking phenomena in the chemical domain were evaluated based on the aspect of nature related to the generation of models. To achieve this, we were targeting statement of textbooks from 7th curriculum to 2009 revised curriculum. Analysis of textbooks was performed for science of elementary school (total 2 textbooks) and science of middle school (total 21 textbooks) which dealt with these phenomena. According to the textbooks analysis, characteristics of statement way were (1) No description of the model's prerequisites, (2) Statement based matter viewpoint, (3) Lack of pattern principle, (4) Inadequacy of the case covered. Although the education about the model for the students should be preceded by the education related to the process of model creation rather than the activity using the model, the education about the nature of the model is insufficient. In order to solve this problem, we propose the model statement in textbooks and the development of the model evaluation tool related to model creation.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1627-1633
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• 2017

This paper proposes a voice enhancing ear-protection system which is based on feedback active noise control(FBANC). The proposed system selectively suppresses the background noise and preserves the talking voice by controlling the adaptive algorithm with the voice activity period detection module. The noise reduction performance of the proposed noise canceling algorithm is analytically derived for the two key performance affecting parameters, i.e., electro-acoustic coupling distance and noise bandwidth. The proposed system is also implemented with a floating-point DSP system and its performance is experimentally tested to compare with the analytically derived results. The achieved levels of noise reduction for the three different noise bandwidths cases, i.e., 10Hz, 50Hz, and 90Hz, are high to show 17.05dB, 10.54dB and 8.99dB, respectively. The feasibility of the proposed system is also shown by the peak noise reduction achieved more than 25dB while preserving the voice component in the frequency range between 200-800Hz.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.273-276
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• 2009

Interior space of large scale composition facilities influences in walk population of distance according to trade and space rescue and walk population of distance is armed business activity. First, chose representative COEX mall of domestic representative multiplex utilization facilities on greate upper limbs for progress of research. Because executing space analysis of COEX mall interior, can analyzed the walk amount and location and also confirm result that floating population according to accessibility increases. Produced time, day of the week, the passageway passing amount through CCTV on actuality COEX mol interior to compare this. Was proved that it is quantity in the passageway passing amount and analysis incidental of the passing amount that get executing space difference.

• Journal of Aquaculture
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• v.10 no.4
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• pp.463-472
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• 1997

Floating and hatching rates, size and survival activity index(SAI) of spawned eggs of red spotted grouper, Epinephelus akaara were studied to understand egg qualities during the spawning periods in 1992, 1993 and 1995. The fish spawned from mid-July to mid-August when temperature ranged 23~$28^\circC$. Floating, fertilization and hatching rates were higher in the eggs from early to middle than those from late during the spawning period. SAI ranged 1.8~9.6, and it was closely related to survival rate until mouth operning time (SMOT). Egg diameter decreased gradually with the time of spawning, while diameter of oil globule was constant during the spawning periods. Induced spawnings were carried out with one injection of HCG over 5, 000 IU/kg body weight. Floating, fertilization and hatching rates of the induced spawning eggs were higher than those of untreated ones. Thus, induced spawning method with HCG was recommended for collecting fertilized eggs in bulk. Optimal time for the collection of high quality eggs was supposed to be from early to middle during the spawning periods. Considering that egg qualities were vulnerable within the period, hatchability, incidence of malformed larvae, SMOT and SAI were factors to be considered together to get good quality of eggs.

• Journal of Conservation Science
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• v.24
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• pp.75-83
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• 2008

In order to assess antifungal activity of a wooden storage box, which was made of Paulownia tomentosa and used for keeping ancient documents, antifungal activity of volatile organic compounds emitted from the box was investigated along with qualitative analysis on major substances of the compounds. After collecting floating microorganisms inside air tester, the fungal activity was assessed by counting the number of colonies growing on TSA media. Compared to the control which collected 85 colonies from outdoor, 72 colonies were observed showing reduction rate of 14.82%. Through GC/MS and TDS system analysis, limonene was detected from the volatile organic compounds as characteristic features. When the fungal activity was assessed through fumigation by adding natural biocide BI and BII containing eugenol and anethole as major substances, both biocides showed a strong fungal activity with respectively 92.6%(inside the box) and 99.9%(outdoor) of reduction rate. Although these results didn't clarify antifungal activity of the volatile organic compounds emitted from the Paulownia-wood storage box and their functional components, it was at least confirmed that there is application possibility of natural biocide to use for preservation of ancient documents with increased efficiency in controlling pests of wooden storage boxes.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.257-275
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• 1984

Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.