• Korean Journal of Ichthyology
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• v.25 no.3
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• pp.149-156
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• 2013

Phylogenetic relationships and DNA polymorphism among local populations of two Korean gobiidae species: Boleophthalmus pectinirostris and Scartelaos gigas were investigated based on 12S and 16S mitochondrial DNA and mitochondrial cytochrome b DNA sequences. DNA polymorphisms of B. pectinirostris between Suncheon and Gunsan populations were 100% identity from 434 bp segment of 12S rRNA gene and from 444 bp segment of mitochondrial cytochrome b genes, and 99.6% (2 bp different) identity from 484 bp segments of 16S rRNA genes. These results indicated the long period of geographic isolation between two populations of B. pectinirostris in Korea caused such high degrees of DNA polymorphisms. Based on the phylogenetic tree constructed from the two gobiid species in Korea, two genetically distinct groups of B. pectinirostris and S. gigas groups were recognized.

• Journal of Sensor Science and Technology
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• v.12 no.2
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• pp.79-87
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• 2003

In this paper, we propose a method to obtain a linear characteristic using soft computing for systems which have array sensors of nonlinear characteristics. Also a procedure utilizing the pattern information of array sensors without additional sensors is proposed to reduce disturbance effects. For a typical example, even a single CdS cell for CdS array has nonlinear characteristics. Overall linear characteristic for CdS array is obtained using fuzzy logic for each cell and overlapped portion. In addition, further improvement for linearization is obtained applying genetic algorithms for the parameters of membership functions. Also the effect of disturbing external light changes to the CdS array can be reduced without using any additional sensors for calibration. The proposed method based on fuzzy logic shows improvements for position measurements and disturbance reduction to external light changes due to the fuzziness of the shadow boundary as well as the inherent nonlinearity of the CdS array. This improvement is shown by applying the proposed method to the ball position measurements of a magnetic levitation system.

• Korean Journal of Plant Taxonomy
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• v.36 no.3
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• pp.189-207
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• 2006

Goodyera rosulacea, which is morphologically similar to G. repens, is described recently as a new species based on its distinct morphological characters such as rosette-formed leaves, short rhizome and habitat. To verify the taxonomic identity of G. rosulacea and its taxonomic relationship within Korean Goodyera taxa, sequences of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA and the trnL region of cpDNA from 24 accessions including 1 outgroup accession were analyzed. Aligned sequences were analyzed using maximum parsimony and distance method, and the taxonomic identity and the taxonomic relationships among the related taxa were estimated by the existence of private marker gene and the phylogenetic tree of the aligned sequences. Molecular data indicate that G. rosulacea gas several private marker genes and shows monophyly in phylogenetic trees of both ITS and trnL sequences. the pairwise distance between G. rosulacea and the orher taxa of Korean Goodyera was 3.49-6.68% for ITS region and 5.05-9.53% for trnL region, indicating that G. rosulacea could be treated as an independent species. Therefore, our molecular data support the taxonomic of G. rosulacea as a distinct species of Korea. In phylogenetic trees, G. rosulacea formed same clade with G. repens, which has similar morphological characters with G. rosulacea, and showed the lowest pairwise distance with G. repens among Korean Goodyera taxa. These molecular data sugguested that G. rosulacea and G. repens are closely related taxa.

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.152-158
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• 2009

We performed RAPD analysis to investigate the inter-/intraspecific relationships and regional variations of Phragmites japonica and P. communis according to the environmental change. One hundred and fourty nine genetic effective polymorphic bands between 300 bp and 1,900 bp were marked from RAPD PCR with nine oligoprimers. From the RAPD analysis by Nei-Li's genetic distance, the dissimilarity indices among the populations of Phragmites japonica were relatively low from 0.012 to 0.061, and Phragmites communis were also low from 0.033 to 0.095. It showed the close genetic relationships among the same species populations, and both species were distinctly independent with relatively high level of dissimilarity indices (0.043 - 0.132). The obvious genetic markers to distinguish two species were confirmed and those profiles were suggested. From the UPGMA phenogram by RAPD analysis, both species showed the water environment related cluster patterns by distributional regions. RAPD analysis was useful to delimit two species taxonomically and to investigate the genetic relationships among inter-/intraspecific populations.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.1811-1817
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• 2014

In this paper, a PID controller with interpolated gains by use of neural networks is proposed for the formation control problem that following robots track a leading robot with constant distances and angles when there are changes in the mass of the following robot. The whole control system is composed of a kinematic controller and a dynamic controller considering the robot dynamics. The dynamic controller is the PID controller with varying gains, and the proper gains are obtained for some representative masses of the follower robot by the genetic algorithm. Neural networks is trained using the genetic algorithm with the gain data obtained in the previous step. The trained neural network determines optimal PID gains for a random mass of following robot. Simulation studies show that for arbitrary masses of the tracking robot, the PID controller with interpolated gains by the trained neural network has better tracking performance than that of the PID controller with fixed gains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.256-260
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• 2004

A major challenge facing those involved in the testing of new plant varieties for distinctness, uniformity and stability (DUS) is the need to compare new varieties against all those of common knowlege (reference varieties). One possible approach would be to group new (candidate) varieties and reference varieties using descriptions stored in databases prior to further of official test. testing. This study was carried out to manage a reference variety collection by databasing of hordein profiling. For this purpose, hordein subunits of the 48 National list barley (Hordeum vulgare L) cultivars were analysed. Total 22 of clear scorable hordein subunits were identified from D-subunit to B-subunit region and fifteen different hordein polypeptide patterns were obtained. Based on hordein subunit band pattern, UPGMA cluster analysis was conducted. Forty-eight cultivars were separated into three groups and genetic distance of cluster ranging from 0.55 to 1.00. Hordein subunits have a potential of selecting similar varieties compared with candidate varieties by controlling reference variety collection and playing an important complemental role in cultivar distinctness.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.355-365
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• 2014

It has been unclear whether the diamondback moth, Plutella xylostella can overwinter in Korean field conditions. This study determined overwintering conditions of P. xylostella by conducting field exposure tests based on its cold tolerance and monitoring overwintering populations by direct examination of overwintering larval habitats and capturing adults with sex pheromone traps. In addition, the overwintering populations were analyzed using polymorphic genetic markers to trace their sources. When all immature stages of P. xylostella were exposed to $-5^{\circ}C$, which was the temperature much above their supercooling points, they significantly suffered with direct cold injuries, where larval stage was most tolerant to the cold injury. However, the exposure to $5^{\circ}C$ for a long period (4 weeks) did not give any significant cold injury to nonfeeding stages, while this treatment gave lethality to larval stage without diet. When all developmental stages of P. xylostella were exposed to open field conditions during winter, they exhibited significant decreases of survival rates. However, some protected and indoor conditions reduced the cold injuries and the diet provision significantly increased larval survival rates. Adult monitoring with sex pheromone during winter period indicated that the first captures were observed at similar periods at different locations (${\approx}260$ Km apart). The overwintering adults were captured until early April. Genetic variation of these overwintering populations was analyzed with polymorphic molecular markers, indicating significant genetic divergences among the overwintering populations. This study indicates that P. xylostella can overwinter in southern Korean fields or some protected greenhouses with host plants.

• The Korean Journal of Zoology
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• v.27 no.3
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• pp.137-150
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• 1984

The present experiments were carried out to understand the genetic structure of the natural population by means of the frequencies of recessive lethal and sterility genes on the second chromosomes of Drosophila melanogaster. The natural populations used for experiment were Anyang, Kimpo and Ulsan populations in 1982 and 1983. The mean frequencies of deleterious gene (lethal plus semilethal) were estimated 29.01% in Anyang, 30.07% in Kimpo and 32.31% in Ulsan population. Allelism rates on the chromosome between lethals extracted from natural populations were examined within or between populations. The mean allelism rates were showed 2.28% in Anyang, 1.90% in Kimpo and 2.17% in Ulsan. The values of elimination $(IQ^2)$ were estimated by frequencies of deleterious genes and allelism rates. The mean values of elimination were 0.0020 in Anyang, 0.0019 in Kimpo and 0.0023 in Ulsan population. The effective population size was estimated by using a formula by Nei. Anyang, Kimpo and Ulsan populations were about 2, 900, 3, 600 and 3, 200, respecively. These data suggest that Korean populations of Drosophila melanogaster attained to stable breeding units of intermediate size, ranging from 2, 900 to 3, 600 pairs of fertile individuals.

• Korean Journal of Ichthyology
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• v.32 no.4
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• pp.210-221
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• 2020

Since the introduction of Israeli carp into Korea for farming in 1973, there are no breeding studies on developing Korea Israeli carp (domestic) so far. This study performed gene-based cross-breeding studies to restore genetic diversity of lowered Israeli carp through continuous inbreeding, and for rapid growth and better scales. This study produced four cross-breeding groups (F1) using Koean Israeli carp and Chinese Songpu mirror carp for the improvement of growth and scale of Israeli carp in Korea. And mating scheme for breeding groups was set in consideration of the morphological analysis and genetic distance of broodstock. In addition, this study used microsatellite markers and genotype data to analyze genetic diversity and parentage analysis. As a result, the average N_A and H_E values of Korean select broodstock are 8.3 and 0.743, and F1 is 13.0 and 0.764. This study shows that the genetic diversity of F1 has been recovered over Korean Israeli carp through breeding between Korean Israeli carp and Chinese Songpu mirror carp. Common Israeli carp in Korea reached 1.7 kg in 17 months, and improved Israeli carp reached to 2.2 kg. The KC (Korea×China, KC) group was 2.52 and broodstock group was 3.15. F1 showed lower scale score (0.63) than broodstock. The improved carp (F1; CK, KC) had 20% better scales than the parent group (F0), which improved 27% in weight and 25% in scales compared to common Israeli carp. The Israeli carp developed by the genetics-based breeding grew quicker and had improved genetic diversity and fewer scales, which will be of great value for Korean Israeli aquaculture industry due to good marketability.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.699-705
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• 2007

The present study was conducted to investigate the genetic characteristic and to establish the parentage verification system of the Korean native horse(KNH). A total number of 192 horses from six horse breeds including the KNH were genotyped using 17 microsatellite loci. This method consisted of multiplexing PCR procedure. The number of alleles per locus varied from 5 to 10 with a mean value of 7.35 in KNH. The expected heterozygosity and observed heterozygosity were ranged from 0.387 to 0.841(mean 0.702) and from 0.429 to 0.905(mean 0.703), respectively. The total exclusion probability of 17 microsatellite loci was 0.9999. Of the 17 markers, AHT4, AHT5, CA425, HMS2, HMS3, HTG10, LEX3 and VHL20 marker have relatively high PIC value(>0.7). This study found that there were specific alleles, P allele at AHT5, Q allele and R allele at ASB23, H allele at CA425, S allele at HMS3, J allele at HTG10 and J allele at LEX3 marker in KNH when compared with other horse populations. Also, the results showed two distinct clusters: the Korean native horse cluster(Korean native horse, Mongolian horse), and the European cluster(Jeju racing horse, Thoroughbred horse). These results present basic information for detecting the genetic markers of the KNH, and has high potential for parentage verification and individual identification of the KNH.