• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.254-260
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• 1982

Ten soybean varieties were cultivated to know the varietal differences of lodging patterns of soybean plants under three different plant populations in two growing seasons in 1981. Lodging plant percentage was increased in higher plant populations and lodging responses to plant populations were different between soybean varieties. Lodging plant percentage was also increased by the growth of soybean plant and the patterns of lodging development along with the growth stages could be classified into four types by the varieties used, relatively lwoer iodging plant percentage from early to later growth stage but high in late and relatively high in middle stage but low in later stage. Williams, indeterminate type, and Kang-lim, determinate type, showed resistance to lodging under six different cultural practices, but Jang-yeop-kong, Dan-yeop-kong and Hwang-keum-kong showed resistance to lodging under specific cultural conditions among ten varieties used. Most of the plants lodged showed main stem bending in parts above first stem node in higher plant population and lodging resistant varieties showed lower frequency of stem bending lodging compared with those of lodging susceptible varieties.

• Korean Journal of Veterinary Service
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• v.32 no.1
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• pp.27-32
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• 2009

We studied the seroprevalence of four respiratory pathogens in Korean swine farms located in Chungnam, Chungbuk, Gyeongnam and Gyeongbuk provinces during the period of spring of 2007 to winter of 2008. Serological tests were performed using commercial ELISA kits. A total of 530 serum samples were tested for the antibodies against porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (M. hyo) and Actinobacillus pleuropneumoniae (APP). Seroprevalence for four respiratory pathogens were estimated by ELISA-positive rates of the submitted samples. The overall seropositive rates of PRRSV, APP, M. hyo and PCV2 were 32.6%, 10.6%, 38.4% and 88.5%, respectively. By production stage, the seropositive rate for PRRSV was highest in nursery pig populations (46.2%). In contrast, the highest seropositive rates of APP and M. hyo were observed in sow and growing pigs. However, the seroprevalence of PCV2 was ranged from 85.7% to 89.6%, showing no significant difference among the production stages. In the seroprevalence by season, PRRSV, APP and M. hyo infections revealed typical seasonal patterns that the peaks of the seropositive rates were observed between early winter and late spring. In case of PCV2, no particular seasonal patterns were noticed. The pig herds in Gyeongbuk province where PMWS was endemic during the period of survey showed the highest seropositive rates for PRRSV (44.6%), M. hyo (47.5%), and PCV2 (92.7%). Seropositive rates for APP of four provinces were approximately 10%. These results might be valuable for control and prevention of the respiratory diseases and helpful to define strategies related to vaccine applications.

• Restorative Dentistry and Endodontics
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• v.38 no.3
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• pp.134-140
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• 2013

Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance and bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study is to compare flexural strength before and after heat treatment of two lithium disilicate CAD/CAM blocks, IPS e.max CAD (Ivoclar Vivadent) and Rosetta SM (Hass), and to observe their crystalline structures. Materials and Methods: Biaxial flexural strength was tested according to ISO 6872 with 20 disc form specimens sliced from each block before and after heat treatment. Also, the crystalline structures were observed using field-emission scanning microscopy (FE-SEM, Hitachi) and x-ray diffraction (XRD, Rigaku) analysis. The mean values of the biaxial flexural strength were analyzed by the Mann-Whitney U test at a significance level of p = 0.05. Results: There were no statistically significant differences in flexural strength between IPS e.max CAD and Rosetta SM either before heat treatment or after heat treatment. For both ceramics, the initial flexural strength greatly increased after heat treatment, with significant differences (p < 0.05). The FE-SEM images presented similar patterns of crystalline structure in the two ceramics. In the XRD analysis, they also had similar patterns, presenting high peak positions corresponding to the standard lithium metasilicate and lithium disilicate at each stage of heat treatment. Conclusions: IPS e.max CAD and Rosetta SM showed no significant differences in flexural strength. They had a similar crystalline pattern and molecular composition.

• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.931-938
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• 2018

D-CATV VOD service provides various contents such as drama and movie with high quality regardless of time and place. As the usage time of the VOD service increases, the viewing time of real-time terrestrial broadcasting is shortened. As the demand for VOD service is high and the number of digital users is increasing, the VOD market is rapidly growing. Therefore this study investigates the age and gender analysis of digital cable TV users and analyzed the usage patterns and audience cases of users. VOD service has been shown to be used by many users for the first time through remote control and free coupons. Non-users of VOD service did not use it because of charge and did not feel the necessity, but some non-users did not recognize the free VOD service.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.510-512
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• 2019

Recently, there have been growing requirements in the public safety sector to ensure safety through detection of hazardous situations or preemptive predictions. It is noteworthy that various sensor data can be analyzed and utilized as a result of mobile device's dissemination, and many advantages can be used in terms of safety and security. An effective modeling technique is needed to combine sensor data generated by smart-phones and wearable devices to analyze users' moving patterns and behavioral patterns, and to ensure public safety by fusing location-based crime risk data provided.

• Korean Journal of Remote Sensing
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• v.38 no.1
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• pp.83-101
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• 2022

Accurate atmospheric correction is essential for the analysis of land surface and environmental monitoring. Aerosol optical depth (AOD) information is particularly important in atmospheric correction because the radiation attenuation by Mie scattering makes the differences between the radiation calculated at the satellite sensor and the radiation measured at the land surface. Thus, it is necessary to use high-quality AOD data for an appropriate atmospheric correction of high-resolution satellite images. In this study, we examined the Second Simulation of a Satellite Signal in the Solar Spectrum (6S)-based atmospheric correction results for the Sentinel-2 images in South Korea using raster AOD (MODIS) and single-point AOD (AERONET). The 6S result was overall agreed with the Sentinel-2 level 2 data. Moreover, using raster AOD showed better performance than using single-point AOD. The atmospheric correction using the single-point AOD yielded some inappropriate values for forest and water pixels, where as the atmospheric correction using raster AOD produced stable and natural patterns in accordance with the land cover map. Also, the Sentinel-2 normalized difference vegetation index (NDVI) after the 6S correction had similar patterns to the up scaled drone NDVI, although Sentinel-2 NDVI had relatively low values. Also, the spatial distribution of both images seemed very similar for growing and harvest seasons. Future work will be necessary to make efforts for the gap-filling of AOD data and an accurate bi-directional reflectance distribution function (BRDF) model for high-resolution atmospheric correction. These methods can help improve the land surface monitoring using the future Compact Advanced Satellite 500 in South Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.3
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• pp.109-119
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• 2016

This study was conducted to analyze the effect of yearly changes in growing degree days (GDD) on the potential distribution and growth of Quercus mongolica in Korea. Annual tree-ring growth data of Quercus mongolica collected by the $5^{th}$ National Forest Inventory were first organized to identify the range of current distribution for the species. Yearly GDD was calculated based on daily mean temperature data from 1951 to 2010 for counties with current distribution of Q. monglica. When tree-ring growth data were analyzed through cluster analysis based on similarity of climatic conditions, seven clusters were identified. Yearly GDD based on daily mean temperature data of each county were calculated for each of the cluster to predict the change of potential distribution. Temperature effect indices were estimated to predict the effect of GDD on the growth patterns. In addition, RCP 4.5 and RCP 8.5 of climate change scenarios were adopted to estimate yearly GDD and temperature effect indices from 2011 to 2100. The results indicate that the areas with low latitude and elevation exceed the upper threshold of GDD for the species due to the increase of mean temperature with climate change. It was also predicted that the steep increase of temperature will have negative influences on tree-ring growth, and will move the potential distribution of the species to areas with higher latitude or higher elevation, especially after the year of 2050. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics and for predicting changes in the potential distribution of Q. mongolica caused by climate change.

• The Korean Journal of Mycology
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• v.24 no.3 s.78
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• pp.186-205
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• 1996

This study was carried out to obtain data concerning the genetic variability of Pleurotus ostreatus. Monospores of P. ostreatus were isolated and cultured to estimate differences in the rate of mycelial growth and genetic similarity among the isolates. Although the overall growth rates were slow compared to their parental dikaryon except 2-MI 4, significant differences in the rate of mycelial growth were observed among isolates. Random amplified polymorphic DNA (RAPD) analysis using twenty six random primers showed 345 polymorphic DNA bands from 35 monospore isolates and their parental dikaryon. DNA bands ranged from 0.1 to 4.0 Kb in size. Most various polymorphic DNA bands within monospore isolates were obtained when we used J (OPA-01) or W (OPB-04). The 36-MI 103 showed totally different band patterns from those of the others. RAPD analysis revealed that there is approximatly 75% genetic similarity between monospore isolates and their parental dikaryon except 36-MI 103, which showed only 49% genetic similarity. In addition, genetic similarity degrees were classified into four groups: I (parental dikaryon), II (fast growing type), III (moderate growing type), and IV (slow growing type). However, there is no correlation between mating type and mycelial growth rates.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.304-310
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• 1997

In greenhouse, a mixed solution of Mn-54, Co-60, Sr-85 and Cs-137 was applied to the soil of culture boxes 2 days before sowing cucumber and at 4 different times during its growth for measuring their transfer factors (TFs) for fruit and migration in soil. TFs varied with radionuclide, application time and harvest time by factor of up to about 60. Variations in TFs with application time showed different patterns among radionuclides. TFs decreased on the whole in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. TFs of Mn-54, Co-60 and Cs-137 mixed with topsoil before sowing were a little higher than those for the soil-surface application made at an early growth stage while no difference in Sr-85 TF was found. After harvest, soil concentrations of the radionuclides applied at an early growth stage were examined. They decreased with increasing soil depth and 80${\sim}$99% of the radioactivity remained in the top 3cm. Soil pemeation of the radionuclides migration decreased in the order of Sr-85 > Mn-54 > Co-60 > Cs-137. The present data can be utilized in estimating radionuclide concentration in cucumber fruit, taking proper measures for its harvest and consumption and designing the best way of soil decontamination following an radioactive deposition during the cucummber growing season.

• Molecules and Cells
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• v.20 no.1
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• pp.97-104
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• 2005

To investigate apoptosis in HC11 mammary epithelial cells, we compared the gene expression profiles of actively growing and serum-starved apoptotic cells using a mouse apoptosis gene array and $^{33}P$-labeled cDNA prepared from the RNA of the two cultures. Analysis of the arrays showed that expression of several genes such as clusterin, secreted frizzled related protein mRNA (sFRP-1), CREB-binding protein (CBP), and others was higher in the apoptotic cells whereas expression of certain genes including survivin, cell division cycle 2 homolog A (CDC2), and cyclin A was lower. These expression patterns were confirmed by RT-PCR and/or Northern analyses. We compared the expression of some of these genes in the mouse mammary gland under various physiological conditions. The expression levels of genes (clusterin, CBP, and M6P-R) up-regulated in apoptotic conditions were higher at involution than during lactation. On the other hand, genes (Pin, CDC2) downregulated in apoptotic conditions were relatively highly expressed in virgin and pregnant mice. We conclude that certain genes such as clusterin, sFRP-1, GAS1 and CBP are induced in apoptotic mammary epithelial cells, and others are repressed. Moreover, the apoptosis array is an efficient technique for comparing gene expression profiles in different states of the same cell type.