• Weed & Turfgrass Science
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• v.7 no.3
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• pp.201-208
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• 2018

This study was conducted to investigate the occurrence and distribution of herbicide resistant weeds at rice fields in Chungnam province of Korea in 2017. Herbicide-resistant weeds occurred in 64,782 ha, which comprise 47.0% of the total paddy field area of Chungnam province. The infested area of herbicide resistant weeds was estimated in Seosan-si (11.9%), Nonsan-si (11.1%), Dangjin-si (10.9%), Boryeong-si (9.2%) and Asan-si (7.8%). The most dominant herbicide resistant weeds in rice fields were Monochoria vaginalis, followed by Lindernia dubia, Schoenoplectus juncoides, Echinochloa oryzicola, Cyperus difformis and Sagittaria trifolia. Herbicide resistant M. vaginalis, L. dubia, and S. juncoides occurred throughout Chungnam province, and herbicide resistant S. trifolia was only found in Dangjin-si. Compared with the 2011 survey, the infested area of herbicide-resistant weeds decreased, but the incidence rates were similar. The herbicide rotation with different modes of actions across growing seasons is recommended to control herbicide-resistant weeds in the infested fields. It is necessary to monitor herbicide resistance regularly and conduct integrated herbicide resistance management in this area.

• The Korean Journal of Malacology
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• v.19 no.1
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• pp.71-79
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• 2003

After the juvenile octopus individuals being discharged, it is hard to separately capture them because they attach strongly to the wall of the aquarium by the suckers on the arms. Therefore, anaesthetics (MS-222 or lidocaine-HCl) are usually used for capture from attachment. The anaesthetized time of the octopus by lidocaine-HCl was more faster 1.6 to 4.5 times under 200 ppm and 6.0 to 6.5 times in 300 to 500 ppm than those in MS-222. In the anaesthetized and recovery rates (%) by the exposed time, the juvenile octopuses were anesthetized by lower concentrations of lidocaine-HCl within the short time, and rapidly recovered from anesthesia. In the secondary anesthesia of the juvenile octopuses exposed with lidocaine-HCl by the elapsed time after the primary anesthesia, the anesthetized time was later in case of lower concentrations and long elapsed times, However, the anesthetized time was faster when their concentrations were higher and the elapsed time after anesthesia were shorter. Recovery from the secondary anesthesia was faster when the elapsed time was long in lower concentration, and was later when the elapsed time was shorter. In case of Octopus ocellatus, anaesthetic effects by lidocaine-HCl concentrations were better than those of MS-222. Doses of lidocaine-HCl and critical time for works at the indoor laboratory were proper in concentration of 100 ppm within 15 min.

• Korean Chemical Engineering Research
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• v.52 no.3
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• pp.314-320
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• 2014

Regarding the design of the gas sweetening absorber, the gas distribution analysis for the increase of the sour gas removal and reduction of the tower height is very important research topics. Recently, regarding the $CO_2$ capture technology which is a promising option for the reduction of the greenhouse gas (GHG), the need for the gas distribution improvement is increased as the gas treating capacity increases. In this paper, we have investigated the sour gas distribution in the absorber using CFD (Computational Fluid Dynamics) based on 10 MW post-combustion $CO_2$ capture plant installed in Boryeong power station, Korea Midland Power company. For this purpose, we suggested the three possible technology options (splash plate, spiral gas line and U-tube) for the gas distribution enhancement and compared the effect of the each cases. The result showed that the U-tube installed in the absorber increase the gas distribution about 30% compared to the base case, while the delta P increasement was about 10%. From these results, it was found that the U-tube installation is an effective technology option for the gas distribution enhancement in the gas sweetening absorber.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.519-535
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• 2012

In order to establish a rainfall-runoff model, calibration of hydrological parameters for the model is very important. Especially, Curve Number(CN), estimated by NRCS method, is a main factor to apply unit hydrograph theory to calculation of peak discharge. For using NRCS method, it is needed selecting AMC because CN is strongly connected with that. In this study, we focus our concern on finding a applicable standard for selecting AMC for CN. For this, three dams which are Boryeong, Habchon, Namgang are selected as target basins to use observed data including rainfall and dam inflow. As a result of this research, it is found that CN must be included as a calibrated parameter to calculate effective rainfall for the rainfall-runoff model. Also, it is preferred to use PWRMSE of HEC-HMS program as a objective function for optimizing hydrological parameters. From the analyzing result of variation of AMC for peak discharge, it is recommended to apply AMC-III to estimation of CN for calculating effective rainfall of design hydrograph.

• The Journal of the Petrological Society of Korea
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• v.24 no.3
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• pp.273-289
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• 2015

This study used the petrological features and the whole rock susceptibility characteristics suggest ways to determine the domestic dimension stones and Chinese similar dimension stones. In addition, this study compare the intrusive period by measuring the zircon U-Pb age of these stones. Result of comparing the petrological feature, with the exception of Macheon stone and Boryeong stone to show the differences in mineral composition and texture under a microscope, the domestic dimension stones and Chinese similar dimension stones exhibit substantially the same petrological feature. According to the measurement results for the whole rock magnetic susceptibility, Goheong, Iksan, Pocheon stones are the similar as Chinese dimension stones, and other stones are easily distinguished. The zircon U-Pb age results for Geochang, Iksan, and Pocheon stones are equivalent to the Jurassic Daebo granites and G603, G633, G655 are the Cretaceous granites. Therefore, the domestic dimension stones and Chinese similar dimension stones can be clearly determined by the zircon U-Pb age results.

• Fire Science and Engineering
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• v.32 no.1
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• pp.89-98
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• 2018

Fire accidents in foreign countries, like the accident in a thermal power plant in Beijing, the accidents in domestic power plants, including Boryeong Power Plant in 2012 and Taean Power Plant in 2016, a disaster in a nuclear power plant in Fukushima in 2011 or the large-scale power failure in California in 2001 are safety accidents related to electric power, which caused losses in the people's stable lives and the countries. Electricity has an absolute impact on the people's life and the economy, so we can easily expect the serious situation affecting economic growth as well as direct damage to the protection of the people's lives and the losses of properties, if there are fire or explosion accidents or radioactive leak because of negligence in safety management, or problems because of natural disasters like an earthquake in power plants that generate electricity. In this study, it was drawn the improvement of the organizations exclusively in charge of firefighting, the operation of a program for the improvement of professional competency, the development of a customized firefighting management system for plants for systematic firefighting safety management and the improvement of the earthquake-proof correspondence system, which has recently become an issue, as measures for improvements through a survey of the actual conditions concerning the necessity of the construction of a firefighting safety management system for power plants with five power generation companies, including Korea Southern Power Co., Ltd., and the persons in charge of firefighting safety Korea Hydro & Nuclear Power Co., Ltd.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.59-65
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• 2012

The black pine bast scale, $Masucoccus$ $thunbergianae$ (Hemiptera: Margarodidae), is a serious pest of the Japanese black pine, $Pinus$ $thunbergii$, in Korea. The distribution of the black pine bast scale was examined, looking overall at 686 towns (eup), townships (myeon) or neighborhoods (dong). There were Japanese black pine ($Pinus$ $thunbergii$) forests in 91 cities, counties (gun) and borough (gu), in seven provinces and three metropolitan cities during 2010. Black pine bast scale were found in 64.8% of cities or counties or borough (59) in 7 provinces and 3 metropolitan cities, and were distributed in all South Costal regions, Pohang in East Costal region and Boryeong in West Costal region. Chungcheongbukdo, Daejeon and Jeju did not have black pine bast scale. All the gu regions in Busan had black pine bast scale, of which the area with the highest prevalence was Haenam in Jeollanamdo (1.713 crawlers/0.785 $cm^2$). Songji-myeon had the highest occurrence rate (6.36 crawlers/0.785 $cm^2$) from the towns, township and dong. The density of black pine bast scale in twigs was highly correlated with percentage of the sample with scale (Correlation coefficacy=0.89).

• Korean journal of applied entomology
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• v.55 no.4
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• pp.471-475
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• 2016

The dark-winged fungus gnats are one of the most serious fly pests attacking the mushroom cultivation in Korea. They cause severe damage to the artificial sawdust beds used to cultivate mushroom, and reduce the production of button mushroom, Agaricus bisporus, in greenhouses. In this study, we collected nine species of the mushroom flies in order to identify the dominant species of the dark-winged fungus gnat attacking the A. bisporus plantation using the yellow sticky trap in Buyeo-gun, Boryeong-gun, Yongin-si and Chilgok-gun from April to June 2015. The collected samples were used to determine the DNA sequence of the cytochrome c oxidase subunit I (COI) of the nine different species by DNA barcoding. The sequencing results showed that Lycoriella ingenua was the dominant dark-winged fungus gnat species destroying A. bisporus cultivated on the artificial sawdust beds in Korea.

• Korean Journal of Ichthyology
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• v.30 no.2
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• pp.75-83
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• 2018

This study is to observe species identification and early life history of Korean endemic species of Tanakia latimarginata and to use it as a basis for taxonomic studies. As a result of morphological identification, a dark band appeared at the margin of the anal fin, and the ovipositor color of the female was light orange. The shape of the egg was fusiform and sticky. The egg size (long${\times}$short diameter) averaged $4.41{\times}1.44mm$. The incubation time was 126 hours after the fertilization at an average water temperature of $21.0^{\circ}C$. Immediately after hatching, the larvae had egg yolk at an average total length of $5.91{\pm}0.18mm$ (n=5). At 18 days after hatching, the trunk fur was developed in the caudal fin with an average total length of $8.02{\pm}0.08mm$ (n=5). At 41 days after hatching, the larvae absorbed egg yolk at an average total length of $8.70{\pm}0.23mm$ (n=5). At 80 days after hatching, the average length of the fins was $12.6{\pm}0.28mm$ (n=5). The number of fin of the dorsal fin was iii.8, the anal fin iii.9~10, the caudal fin 19, lateral line scales 32~35 were similar to their brood stork.

• Journal of Korea Water Resources Association
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• v.47 no.9
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• pp.753-766
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• 2014

The future mean sea level rise (MSLR) due to climate change in major harbors of Korean Peninsula has been estimated by some statistical methods in this article. Firstly, Mann-Kendall non-parametric trend test to find some trend in the observed long-term tidal data has been performed and also Bayesian change point analysis has been used also to detect the location of change points and their magnitude quantitatively. Especially, in this study, the results from Bayesian change point analysis have been applied to combine 4 future MSLR scenario projections with local MSLR data at 5 tidal gauges. This proposed procedure including Bayesian change point analysis results can improve the step for the determination of starting years of future MLSR scenario projections with 18.6-year lunar node tidal cycle and effectively consider local characteristics at each gauge. The final results by the proposed procedure in this study have shown that the future MSLR in Jeju region (Jeju tidal gauge) is in the largest increment and also the future MSLRs in Western region (Boryeong tidal gauge) and Southern region (Busan tidal gauge) are in the second largest one. Finally, it has been shown that the future MSLRs in Southern region (Yeosu tidal gauge) and Eastern region (Sokcho tidal gauge) seem to be in the relatively smallest growth among 5 gauges.