• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.9-14
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• 2020

Four developed patents have applied for a new type of Composite Cyclone Scrubber followed by the previous research (Cho and Kim, 2017), including dust reducing fan with filters. Regarding target installation and maintenance cost, 64% reduction for investment costs (6.2 billion won vs. 17 billion won) compared to existing road pollution reduction system, while social benefit costs increase by 43% compared to existing road pollution reduction measures (72.6 billion won vs. 50.8 billion won). The composition of the device is an air blower type spiral guide vane, and an injection pressure collecting dust efficiency. A nozzle varies Injection angle and contact range, spray liquid species (waterworks, salty water). The proposed patent tests are circulation water Time-by-Time Spray and collected 41.4% more increased micro dust since the sprayed water meets contaminated gas due to the 45° degree colliding, which is 141% increased conventional dust collector. (Ratio of collection over 85%). As regards the source of collection liquid, circulated rainwater and well water, we expect a huge amount of energy and economically saved eco-friendly system in our patent. Finally, the guided vane and metal filter reduced over 90% micro-dust, while sprayed water cleans the vane and filters, resultantly minimizing the maintenance budget. The preliminary evaluations of the developed design make it possible to reduce not only cheaper maintenance budget due to the characteristic water spraying but the cost of water comes from mainly rain and underground.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.17-32
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• 2013

Reckless development policy, which has continued during the past several decades, caused landscape damage. In order to solve this problem, it is very urgent to conserve the habitat and to establish systematic database. Recently, various researches related to landscape damage have been conducted actively and the necessity of landscape ecological planning based on the biotop mapping has been issued as one of the solutions. Therefore, the purpose of this study is to select the study area, which is located in Guji-meon, Dalseong-gun, Daegu and will be formed into Daegu Science Park, and then to develop and apply the landscape ecological planning model based on biotop mapping in district unit. The results are as follows. Fist of all, according to the results of biotop classification with field survey and literature review, total 13 biotop and total 63 biotop types were classified. According to the first evaluation with B-VAT, total 19 biotop types were classified I grade including natural river with abundant plants(BA) and so on. While V grade, which has lowest value, was classified 16 biotop types including vegetable garden adjacent to river(BC). Also the second evaluation, we analyzed total 30 areas such as 1a, 1b grades, which had special meaning for the conservation of species and biotop. Next, 2a, 2b, 2c grades were analyzed total 82 areas. Secondly, in the compliance with Ecological landscape planning, we divided landscape planning model into two parts such as setting of improvement goal and detailed implement plan. For instance, setting of improvement goal, we classified 9 parts such as conservation region and parts of detailed implement plan, we classified total 28 planning indicators with 4 view such as the region which should be special protected from nature and landscape. Lastly, with the developed landscape model we applied to research areas, made maps, and differentiate proposals in each region. Specially, the final master plan was made to help understand the contents of detailed landscape planning. This study will be a useful data, which can solve the landscape damage problem systematically and control it landscape-friendly with biotop classification, evaluation, landscape ecological planning model, and application method which we developed.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.114-126
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• 2020

Bloom-forming toxic cyanobacteria Microcystis spp. are common in the summer season in temperate freshwater ecosystems. Often, it leads to the degradation of water quality and affects the quality of drinking water. In a previous study, NQ (naphthoquinone) compounds were shown to be effective, selective, and ecologically safe algicides for Microcystis spp. blooms. To analyze the superiority of developed NQ derivatives, we conducted a microcosm experiment using clay, which is frequently used in South Korea. Similar to previous studies, the NQ 40 and NQ 2-0 compounds showed high algicidal activities of 99.9% and 99.6%, respectively, on Microcystis spp. at low concentrations (≥1 μM) and enhanced phytoplankton species diversity. However, when treated with clay, a temporary algicidal effect was seen at the beginning of the experiment that gradually increased at the end. In addition, treatment with the NQ compounds did not affect either the abiotic or biological factors, and similar trends were observed with the control. These results showed that the NQ 2-0 compound was more effective, with no ecosystem disturbance, and more economical than the currently used clay. These results suggest that NQ 2-0 compound could be a selective, economically and ecologically safe algicide to mitigate harmful cyanobacterial blooms in the field.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.318-321
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• 2013

National Academy of Agricultural Science and eight province Agricultural Research & Extension Services investigated the occurring area of herbicide resistant weeds in paddy field of Korea. In order to estimate the occurring areas of herbicide resistant weeds, we collected paddy soils randomly from 3,200 sites in 2011 and 2012, and treated 30 kg $ha^{-1}$ of pyrazosulfuron-ethyl+pyriminobac-methyl GR to the paddy soil. 176,870 ha, approximately 22.1% of cultivated area excluding organic and eco-friendly cultivated area, was estimated to be infested by SUherbicide resistant paddy field weeds. Several species of resistant weeds were occurred at Jeonranam-do with 44.3%, followed by 30.5% at Chungchungnam-do, 27.8% at Chungchungbuk-do, and 24.5% at Jeonrabuk-do, respectively. Monochoria vaginalis showed the highest distribution with 57,018 ha, 32.2% followed by Scirpus juncoides, and Lindernia procumbens, respectively.

• Research in Plant Disease
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• v.20 no.3
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• pp.201-205
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• 2014

Damping-off, caused by Rhizoctonia solani and Pythium ultimum, is a very important plant disease and affects seeds and seedlings of many plant species worldwide. To investigate control efficacy of Serenade formulation (1.34%, SC) against Rhizoctonia and Pythium damping-off diseases, seeds of chili pepper and cucumber were sown in soils inoculated with R. solani and P. ultimum and Serenade formulation was applied by soil-drenching with 9-, 19-, and 39-fold dilutions. Control values of Serenade formulation on Rhizoctonia damping-off of chili pepper was 58% and 29% for 9- and 19-fold dilutions, respectively. In the case of cucumber Rhizoctonia damping-off, Serenade treatments showed similar control efficacy with damping-off of chili pepper. On the other hand, control efficacy of Serenade formulation on Pythium damping-off of cucumber was less than control effects on Rhizoctonia damping-off. Only Pythium damping-off of chili pepper treated with 9-fold dilution Serenade was statistically different with untreated control. This result suggest that Serenade formulation could be effectively used for controlling Rhizoctonia and Pythium damping-off diseases.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.295-310
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• 2017

This study investigated the growth of five phytopathogenic fungi including Colletotrichum gloeosporioides, Diaporthe citri, Phytophthora capsici and others according to different concentrations of water extract in order to provide reference data for developing environment-friendly agricultural materials using five native Fagaceae species including Quercus acuta, Quercus salicina, Quercus glauca, Quercus gilva and Castanopsis cuspidata var. sieboldii. As the concentration of aqueous extracts of Fagaceae increased according to donor plants, the mycelial growth of phytopathogens showed a decreasing tendency. Differences were found in the degree of inhibition according to types of donor plants and pathogenic fungi. Diaporthe citri, Phytophthora capsici, Pythium graminicola on the water extract of Castanopsis cuspidata var. sieboldii inhibited mycelial growth by 84% in 25% of the treatment group and by 87% in more than half of the treatment group. The water extract of Quercus acuta was found to have no inhibitory effect against the mycelial growth of Diaporthe citri. The aqueous extracts of Quercus salicina, Quercus glauca and Quercus gilva insignificantly inhibited mycelial growth by approximately 15%. The total phenolic content of receptor plants exhibiting antifungal activity was highest in Castanopsis cuspidata var. sieboldii with a content of 22.32 mg/g phenols, followed by Quercus salicina with 8.32 mg/g, Quercus glauca with 6.83 mg/g, Quercus gilva with 5.95 mg/g, and Quercus acuta with 5.24 mg/g. The aqueous extracts of Castanopsis cuspidata var. sieboldii among the five Five Fagaceae Plants of were the most effective antifungal activity.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.459-464
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• 2016

An outbreak of the migratory locust, Locusta migratoria, in the environment-friendly reclaimed plantations of forage crops in Sanyimyeon, Haenam-gun, Jellanam-do, Korea in August 2014 caused severe damages to various crops. Owing to its first occurrence in the Korean history, the causes underlying the outbreak and phase-transition of the migratory locust were not known. It is critical to establish the genetic relationship of the migratory locust in Sanyimyeon, Haenam-gun with the other previously reported strains in the world in order to understand the mechanisms responsible for its outbreak. The gene sequences of the 16S ribosomal RNA (rRNA) and displacement-loop (D-loop) of the mitochondria of various regional species of the migratory locust were used to perform the phylogenetic analysis. Our results suggested that the migratory locusts in Sanyimyeon, Haenam-gun are closely related with the Eurasian strains of the northern lineage. In future, these two mitochondrial genes can be used for elucidating the genetic population structures in migratory locusts in various regions. In addition, the sequence information of these genes can be used to enhance our understanding of the genetic basis of the outbreak of migratory locusts.

• Resources Recycling
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• v.22 no.5
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• pp.13-19
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• 2013

The effect of pH on the citrate leaching behavior of heavy metal ion was investigated to develop an eco-friendly process for removing heavy metals from soil contaminated with copper, zinc, and lead. The leaching tests were performed using citrate solution with pH adjusted by mixing citric acid and sodium citrate under the following leaching conditions: particle size, under $75{\mu}m$; temperature, $50^{\circ}C$; citrate concentration, $1kmol/m^3$; pulp density, 5%; shaking speed, 100 rpm; leaching time, 1 hour. The difference of pH before and after the leaching test was not observed, and this result indicates the direct effect of hydrogen ion concentration on the leaching of metals was insignificant. The removal ratios of copper, zinc, and lead from the contaminated soil decreased with increasing pH. The thermodynamic calculation suggests that the leaching behaviors of metal ions were determined by two reactions; one is the reaction to form complex ions between heavy metal ions and citrate ion species, and the other is the reaction to form metal hydroxide between heavy metal ions and hydroxide ion.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.403-412
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• 2017

To investigate the control effect of insect pests by natural enemies, sticky traps were used in commercial tomato greenhouses in Chun-cheon and the experiment fields of Gangwon-do Agricultural Research and Extension Services, Republic of Korea using semi-forcing culture (February to June). We selected low toxicity pesticides, environment-friendly agricultural materials (EFAM), and natural enemies of the study species, combinations of which have been previously used in farms to control insect pests. In this study, Trialeurodes vaporariorum and thrips, which are major agricultural insect pests, were studied in experimental greenhouses. The adult T. vaporariorum population was observed in mid-April and the population of thrips showed occurrences in early April. Regarding seasonal fluctuation, T. vaporariorum peaked in mid-May and thrips peaked after June. one insecticide, spiromesifen suspension concentrate (SC); one fungicide, cyazofamid SC; and two EFAMs containing neem tree extract were shown to be slightly toxic to Encarsia formosa and Orius laevigatus. The results of this study could be used to develop management models using natural enemies of control the insect pests; T. vaporariorum and thrips in semi-forcing culture of tomato.