• ETRI Journal
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• v.34 no.1
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• pp.114-117
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• 2012

A small-sized ($15mm{\times}30mm$) planar monopole MIMO antenna that offers high-isolation performance is presented in this letter. The antenna is miniaturized using inductive coupling within a meander-line radiator and capacitive coupling between a radiator and an isolator. High isolation is achieved by a T-shaped stub attached to the ground plane between two radiators, which also contributes to the small size using a folded structure and the capacitive coupling with radiators. The proposed antenna operates for the WLAN band within 2.4 GHz to 2.483 GHz. The measured isolation (S21) is about -30 dB, and the envelope correlation coefficient is less than 0.1.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.59-65
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• 2011

For investigation of the Korean ciliate fauna, two oxytrichid ciliates, Histriculus histrio (Muller, 1773) and Sterkiella thompsoni Foissner, 1996, were collected from freshwater and brackish waters in South Korea, respectively. These two ciliates are reported for the first time in Korea. Descriptions were based on observations of live and silver stained specimens. Diagnoses of these species are as follows. Histriculus histrio: body is approximately $190{\times}85\;{\mu}m$ in size, almost ellipsoidal in shape, posterior part rather thin and very translucent. Cortical granules are absent. Both marginal rows are almost confluent at the posterior end. Six dorsal kineties are present. Sterkiella thompsoni: body is approximately $140{\times}50\;{\mu}m$ in size. Body margins are usually in parallel. Cortical granules are absent. Invariably, four dorsal kineties are present. Two caudal cirri are located on the dorsal surface. Three ellipsoidal macronuclear nodules are present.

• Journal of Korean Society of Rural Planning
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• v.14 no.1
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• pp.23-32
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• 2008

Landscape structure is important to understand a complex patterns and interaction with adjacent habitat in rural area. The aim of this study is to analyze relationship between landscape structure and insect spatial distribution in rural area to suggest applicable possibility of landscape structure as biological indicator. For this purpose, first, four landscape structure criteria such as distance from the forest; density of farmland-forest ecotone; landscape continuity; and field size are selected. Secondly, these criteria are applied to Gangsang-myeon, Yangpyeong-gun where mosaic feature are conserved at various spatial scale. Thirdly, application of landscape structure criteria is verified using correlation with species number, species diversity, and species richness of insect. As a result, it could be suggested that the landscape structure criteria are useful for explaining insect spatial distribution.

• Animal Systematics, Evolution and Diversity
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• v.37 no.1
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• pp.33-38
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• 2021

Three species of Spilomelinae, Camptomastix septentrionalis Inoue, 1982, Omiodes indistinctus (Warren, 1892) and Piletocera aegimiusalis (Walker, 1859), are reported for the first time from Korea. Camptomastix septentrionalis is distinguished from Camptomastix hisbonalis (Walker, 1859) in the smaller body size, the lack of a clear discal spot on the forewings, and having the less protruding costa of the valva in the male genitalia and the smaller antrum in the female genitalia. Omiodes indistinctus is distinguished from Omiodes tristrialis(Bremer, 1864) in having the narrower forewings with the faded postmedian and subbasal lines and a densely-setose, sclerotized area on the terminal part of uncus dorsally in the male genitalia. Piletocera aegimiusalis is distinguished from Piletocera sodalis(Leech, 1889) in the larger body size and the lack of a pale yellow patch on the hindwings. Photos of the external and genital features are provided for the three newly-recorded spilomeline species.

• Animal Systematics, Evolution and Diversity
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• v.12 no.3
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• pp.203-210
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• 1996

Four external and 27 cranial characters of Korean field mice (Apodemus peninsulae) from nine regions in China and Korea, representing three subspecies, were analyzed by multivariate methods. Four size-forms were recognized a largest-size form Mt. Weolak and Yeoncheon in Korea (= subspecies peninsulae) and Kirin and Heilung in China (= subspecies praetor), a large-size form from Inner Mongolia in China (= subspecies praetor) and Sanxi and Sandong in China (= subspecies sowerbyi), a middle-size form from Beijing in China (= subspecies sowerbyi), and a small-size form from Xinjiang in China (= subspecies sowerbyi). Although Corbet (1978) recognized only two subspecies in A. peninsulae, subspecies peninsulae and sowerbyi, within its distributional range in the continent of Asia, it was revealed in this study with morphometric characters that A. peninsulae could not be classified simply into two subspecies, because subspecies praetor and subspecies sowerbyi formed the large-size form and because subspecies sowerbyi was so diverse in its morphology as to be composed of three size-forms. Further analyses with the samples from other regions of China and Russia seem to be necessary to clarify the taxonomy of A. peninsulae.

• Animal Systematics, Evolution and Diversity
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• v.7 no.2
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• pp.179-188
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• 1991

In order to determine the taxonomic status of Apodemus agrarius chejuensis from Cheju island in Korea, three hundred and eleven samples of eight subspecies of striped field mice (subspecies, agrarius, ningpoensis , pallidior, chevrieri, insulaemus, manchuricus, coreae, and chejuensis of A. agrarius Pallas) in Asia, collected from Turkey , China, Taiwan, , Manchuria, and Koarea, were used. Four external and 27 cranial characters were measured and their measurements were utilized for multivariate analyses such as cluster, principal component, and discriminant analyses. Four forms were revealed . A largest-size from was chejuensis, whereas a large-size form was cheverieri. A medium -size from and a small-size from were coreae and other five subspecies (agrarius , ningpoensis, pallidior, insulaemus, and manchuricus) , respecitvley, but their differences were clinal. A discontinuous gap was revealed between chejuensis (a largest-size from) and six subspecies ( a medium-size from and a small-size form) Although chejuensis appeared to be a distinct species, it is concluded that molecular analyses are necessary in order to describe it as a new species.

• Mycobiology
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• v.38 no.1
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• pp.17-25
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• 2010

The common split-gilled mushroom, Schizophyllum commune is found throughout the world on woody plants. This study was initiated to evaluate conditions for favorable vegetative growth and to determine molecular phylogenetic relationship in twelve different strains of S. commune. A suitable temperature for mycelial growth was obtained at $30^{\circ}C$. This mushroom grew well in acidic conditions and pH 5 was the most favorable. Hamada, glucose peptone, Hennerberg, potato dextrose agar and yeast malt extract were favorable media for growing mycelia, while Lilly and glucose tryptone were unfavorable. Dextrin was the best and lactose was the less effective carbon source. The most suitable nitrogen sources were calcium nitrate, glycine, and potassium nitrate, whereas ammonium phosphate and histidine were the least effective for the mycelial growth of S. commune. The genetic diversity of each strain was investigated in order to identify them. The internal transcribed spacer (ITS) regions of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 129 to 143 bp and 241 to 243 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical. A phylogenetic tree of the ITS region sequences indicated that the selected strains were classified into three clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by random amplification of polymorphic DNA (RAPD) with 20 arbitrary primers. Twelve primers efficiently amplified the genomic DNA. The number of amplified bands varied depending on the primers used or the strains tested. The average number of polymorphic bands observed per primer was 4.5. The size of polymorphic fragments was obtained in the range of 0.2 to 2.3 kb. These results indicate that the RAPD technique is well suited for detecting the genetic diversity in the S. commune strains tested.

• Journal of Animal Science and Technology
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• v.57 no.12
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• pp.47.1-47.10
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• 2015

Background: Knowledge of linkage disequilibrium (LD) levels among different populations can be used to detect genetic diversity and to investigate the historical changes in population sizes. Availability of large numbers of SNP through new sequencing technologies has provided opportunities for extensive researches in quantifying LD patterns in cattle breeds. The aim of this study was to compare the extent of linkage disequilibrium among Iranian cattle breeds using high density SNP genotyping data. Results: A total of 70 samples, representing seven Iranian indigenous cattle breeds, were genotyped for 777962 SNPs. The average values of LD based on the $r^2$ criterion were computed by grouping all syntenic SNP pairwises for intermarker distances from 0 Kb up to 1 Mb using three distance sets. Average $r^2$ above 0.3 was observed at distances less than 30 Kb for Sistani and Kermani, 20 Kb for Najdi, Taleshi, Kurdi and Sarabi, and 10 Kb for Mazandarani. The LD levels were considerably different among the Iranian cattle breeds and the difference in LD extent was more detectable between the studied breeds at longer distances. Lower level of LD was observed for Mazandarani breed as compared to other breeds indicating larger ancestral population size in this breed. Kermani breed continued to have more slowly LD decay than all of the other breeds after 3 Kb distances. More slowly LD decay was observed in Kurdi and Sarabi breeds at larger distances (>100 Kb) showing that population decline has been more intense in more recent generations for these populations. Conclusions: A wide genetic diversity and different historical background were well reflected in the LD levels among Iranian cattle breeds. More LD fluctuation was observed in the shorter distances (less than 10 Kb) in different cattle populations. Despite of the sample size effects, High LD levels found in this study were in accordance with the presence of inbreeding and population decline in Iranian cattle breeds.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.7
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• pp.1537-1543
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• 2010

This paper describes a compact microstrip antenna with dual polarization characteristics. The antenna, receiving both a left-hand circularly polarized(LHCP) wave and a right-hand circularly polarized(RHCP) wave, can be used for a polarization diversity. A diamond-shaped patch with internal empty room is designed for impedance matching as well as size reduction. And slots are added around feeding point to improve input matching. The proposed antenna has been applied to GPS(global positioning system), operating at 1.57GHz. And, the proposed idea has been verified and estimated by simulation. The measurement results show that it has VSWR 2:1 bandwidth of 83MHz, 3dB axial bandwidth of about 58MHz, 3dB beamwidth of 90degree, and gain of 0dBi, respectively, for RHCP. Also, it has similar performances for LHCP.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1069-1074
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• 2009

This study investigated soil microbial community and growth of Zea mays to compare the toxicity of nano and micro-sized Cu and Zn oxide particles in microcosm system. In the presence of nanoparticles, biomass of Zea mays reduced by 30% compared with micro-sized particles and inhibited growth. Dehydrogenase activity was inhibited by CuO nano although it was increased by ZnO nano particles. According to the Biolog test, the microbial diversity was decreased after exposed to CuO nanoparticles and ZnO microparticles. Therefore, though it is widely recognized that nanoparticles are more harmful than microparticles, we can conclude that the diversity of microbial community does not always influenced by the size of particles of nano and micro.