• Research in Plant Disease
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• v.15 no.3
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• pp.170-174
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• 2009

In this paper, we report a characterization of Prunus necrotic ringspot virus (PNRSV) isolate. The virus was identified from 'Yumyeong' peach showing mild mosaic on leaves in commercial orchard of 'Umsung', Chungbuk province in Korea. The virus isolate produced ringspot symptom on the inoculated cotyledons and systemic mosaic and malformation on the upper leaves of Cucumis sativus. Systemic mottles were appeared in Chenopodium quinoa. When the buds of the virus infected stem were grafted on the healthy young Prunus persica GF305 seedlings, line pattern with mosaic appeared within 3 months. Isometric virus-like particles were found in parenchyma cells and plasmodesmata of C. sativus leaves inoculated mechanically with the virus. The cDNA fragments of PNRSV coat protein (CP) region, approximately 675bp, were synthesized from genomic RNA extracted from virus-infected leaves by RT-PCR using specific primer pairs. Partial nucleotide sequences of the CP regions were determined and analyzed with the known PNRSV. The CP gene of PNRSVKorea isolates showed 93.9~94.7% similarity to the 4 known PNRSV isolates.

• Land and Housing Review
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• v.3 no.4
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• pp.433-449
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• 2012

An experimental investigation was conducted to study the behavior of RC wide beam-column joints with slab subjected to reversed cyclic loads under constant axial load. Six half scale interior wide beam-column assemblies representing a portion of a frame subjected to simulated seismic loading were tested, including three specimens without slab and three specimens with slab. The primary variables were the ratio of column-to-beam flexural capacity ($M_r={\Sigma}M_c/{\Sigma}M_b$ ; 0.77~2.26), ratio of the column-to-beam width (b/H ; 1.54, 1.67). Test results are shown that (1) the current design code and practice for interior joints(type 2) are apply to the wide beam-high strength concrete column. (2) the presence of a slab have an effect on the performance of the wide beam-high strength concrete column interior joints(type 2). therefore in the design of the wide beam-high strength concrete column interior joints(type 2), the width of slab effective as a T beam flange should be considered. It was show that the case of the ratio of column-to-beam flexural capacity is more than 2.0, the effective width of slab are 2 times of an effective depth of wide beam, however if the ratio of column-to-beam flexural capacity is 1.4~2.0, the effective width of slab are not able to be considered.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.164-170
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• 2020

The weather conditions, such as temperature, precipitation, and sunshine duration, play one of the key roles in Agriculture. In particular, extreme weather events have crucial impacts on growth and yields of crops. This study estimates statistics of extreme weather events in 167 Si-gun over South Korea derived from high-resolution(30 and 270m) topo-climatology model for key three meteorological variables(temperature, precipitation and sunshine duration). It is shown that the characteristic of each extreme weather frequency in the topo-climatology model is in good agreement with observation from Korean Meteorological Administration's Automatic Surface Observing System. Moreover, it is possible to analyze the statistics of extreme weather more realistically because this data can cover the weather at not-observed regions. Hence, this data is expected to be used as baseline data for assessing vulnerability to extreme weather and politic decisions for damage reduction in agricultural sector.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.381-387
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• 2010

This study was performed to investigate differences of antioxidant activity, the content of free amino acids including GABA(gama-amino butyric acid) among mungbean cultivars grown in Highland area (Jinbu) and to compare those between seeds and sprouts. In DPPH (diphenyl picrydrazyl) radical scavenging activity, 'Jangan' mungbean activity was more higher than that of other cultivars. The content of total phenolic compounds of mungbean ranged from 1,186 to $1,493\;{\mu}g/g$ in seed and 2,321 to $2,783\;{\mu}g/g$ in sprout. Among amino acids of seeds, the content of glutamic acid was highest in 'Soseon' mungbean, and contents of almost amino acids increased during sprouting of seeds. The content of GABA that are known as a material having high functional effects on human body was also analyzed. When the relatively high content of GABA was observed in seeds of almost mungbean grown in highland, and their contents rapidly increased after sprouting from seeds. As a result of this experiment, it is expected that mungbean will be developed to a good alternative crop having high value as functional food materials in highland area of Korea.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.590-603
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• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.132-139
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• 2017

A huge amount of de-icing agent is sprayed during winter to promote traffic safety in cold regions, and the quantity of de-icing agent sprayed has increased each year. The main ingredients in commonly used de-icing agents are chlorides, such as calcium chloride($CaCl_2$) and sodium chloride(NaCl). While calcium chloride is mostly used in Korea and sodium chloride is usually used in the U.S. and Japan, all de-icing agents include chloride ions. The chlorides included in sprayed calcium chloride-based de-icing agents have severe adverse effects, including the corrosion of reinforcing steels through salt damage by infiltrating into road structures, reduced structural performance of pavement or damage to bridge structures, and surface scaling, in combination with freezing damage in winter, as well as water pollution. In addition, the deterioration of paved concrete road surface that occurs after the use of calcium chloride-based de-icing agent accelerates the development of visual problems with traffic structures. Therefore, the present study was performed to prepare an environment-friendly liquid de-icing agent through a reaction between waste organic acids and calcium-based by-products, which are industrial by-products, and to analyze the properties of the de-icing agent in order to evaluate its applicability to road facilities.

• Korean Journal of Poultry Science
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• v.38 no.2
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• pp.89-96
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• 2011

The outbreak of Newcastle disease occurred for the first time at a commercial chicken farm near Ulaanbaatar, Mongolia in August 2010. Newcastle disease virus (NDV) obtained from infected chickens in Mongolia was characterized by biological and molecular biological approches. Mongolian NDV isolate killed all of chicken embryos within 60 h in the mean death time assay, indicating virulent for chicken. A genomic region of 695 nts between nts 1055 of the M gene and 508 of the F gene was amplified by RT-PCR and sequenced. The deduced amino acid sequence of the F protein cleavage site was $^{112}RRQKRF^{117}$, which is a typical sequence of velogenic strains of NDV and is agreement with the result of the MDT assay. The sequence of the partial F gene (nts 47 to 435) was used for genotyping by phylogenetic analysis. The phylogenetic analysis showed that the Mongolian isolate was of genotype VII within class II of NDV. Further phylogenetic analysis on the genotype VII strains revealed that the isolates placed in a genetic sublineage of VIId and most closely related with velogenic strains of NDV circulating in Far-east Asian region especially China, suggesting the introduction of velogenic NDV into Mongolia from neighboring countries.

• Korean Journal of Agricultural Science
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• v.34 no.1
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• pp.37-46
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• 2007

This study was conducted to investigate the antler induction rate and production by artificial induction of antlerogenesis using $CaCl_2$ injection on both periosteum around area of horn development for the frontal bone of a female elk deer which do not have an antler. The results obtained from eleven deers for verifying effect of the female's antler induction on reproduction are as follows: The antler development induction by $CaCl_2$injection is higher on the treatments of 30 and 50% of $CaCl_2$ injection than those on the treatments of 15 %. The antler production is higher on the 30 % $CaCl_2$ injection than those of 15 and 50 % $CaCl_2$ injection. For 30 % $CaCl_2$ injection, the antler production is higher in 1.5 and 2.0 ml of % $CaCl_2$ injection than the other injection level. After the induction of antler development, the birth rate is not changed as of 75~100 %, while the regeneration rate of the antler which was not constant in approximately 45 % for five among eleven female deer. With these results, we assume that the injection concentration and amount of $CaCl_2$ injection are around 30 % and 1.5 and 2.0 ml level which can be not only most effective conditions for the antler induction rate and production, but also these conditions do not influence the reproduction during the period of the female elk's antler development induction.

• Korean journal of applied entomology
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• v.27 no.1
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• pp.28-34
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• 1988

Henosepilachna vigintioctomaculata (Motschulsky) (Coleoptera: Coccinellidae), important pests of agricultural crops in Korea, including eggplant and potato, were collected in the Kyonggido area each summer from 1983 to 1986. Data were recorded for rates of parasitism against each host stage and seasonal activity. The parasitoids NothoserPhus afissae (Watanabe), (Hymenoptera: Proctotrupidae), Uga menoni (Kerrich), (Hymenoptera: Cha1cididae), and Pediobius foveolatus (Crawford), (Hymenoptera: Eulophidae) were reared from the host insects. A solitary larval parasitoid, N. afissae, was reared from 2nd to 4th instar brval hosts, with parasitism being highest in the 3rd instar collection. U. menoni, a solitary larval-pupal parasitoid, was reared from 3rd instar larvae to pupae, and parasitism was highest in the pupal collection. N. afissae and U. menoni occurred during June to September. N. afissae showed relatively high parasitism during the entire study period as compared with other species, while parasitization by U. menoni was highest in July. P. foveolatus, a gregarious larval parasitoid, did not generally appear until September, although it appeared in early August in the southern part of Korea. The number of P. foveolatus emerging from a mummy varied, ranging from 7 to 26 (mean = 13. 8).

• The Journal of the Acoustical Society of Korea
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• v.36 no.1
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• pp.30-38
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• 2017

In this paper, we propose an underwater acoustic sensor fault detection method for passive sonar systems. In general, a passive sonar system displays processed results of array signals obtained from tens of the acoustic sensors as a two-dimensional image such as displays for broadband or narrowband analysis. Since detection result display in the operation software is to display the accumulated result through the array signal processing, it is difficult to determine the possibility where signal may be contaminated by the fault or failure of a single channel sensor. In this paper, accordingly, we propose a detection method based on the analysis of RMSCR (Root Mean Square Crossing-Rate), and the processing techniques for the faulty sensors are analyzed. In order to evaluate the performance of the proposed method, the precision of detecting fault sensors is measured by using signals acquired from real array being operated in several coastal areas. Besides, we compare performance of fault processing techniques. From the experiments, it is shown that the proposed method works well in underwater environments with high average RMS, and mute (set to zero) shows the best performance with regard to fault processing techniques.