• Korean Journal of Biological Psychiatry
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• v.18 no.4
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• pp.176-180
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• 2011

Depressive disorders have strong genetic components. However, conventional linkage and association studies have not yielded definitive results. These might be due to the absence of objective diagnostic tests, the complex nature of human behavior or the incomplete penetrance of psychiatric traits. Imaging genetics explores the influences of genetic variation on the brain function or structure. This technique could provide a more sensitive assessment than traditional behavioral measures in psychiatric studies. Imaging genetics is a relatively new field of psychiatric researches, and may improve our understanding on neurobiology of psychiatric disorders. In this review, current understanding in neurobiology of depressive disorders, especially imaging genetic studies on serotonin transporter will be discussed.

• Journal of Power System Engineering
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• v.17 no.5
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• pp.86-93
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• 2013

This paper proposes the used of genetic algorithm for optimizing PI controller and describes the dynamic modeling simulation for the permanent magnet synchronous motor driven by simplified vector control with the aid of MATLAB-Simulink environment. Furthermore, three kinds of error criterion minimization, integral absolute error, integral square error, and integral time absolute error, are used as objective function in the genetic algorithm. The modeling procedures and simulation results are described and presented in this paper. Computer simulation results indicate that the genetic algorithm was able to optimize the PI controller and gives good control performance of the system. Moreover, simplified vector control on permanent magnet synchronous motor does not need to regulate the direct axis component current. This makes simplified vector control of the permanent magnet synchronous motor very useful for some special applications that need simple control structure and low cost performance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.6
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• pp.767-772
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• 2018

Recently, some meta-heuristic algorithms, such as GA(Genetic Algorithm) and GP(Genetic Programming), have been used to optimize CNN(Convolutional Neural Network). The CNN, which is one of the deep learning models, has seen much success in a variety of computer vision tasks. However, designing CNN architectures still requires expert knowledge and a lot of trial and error. In this paper, the recent attempts to automatically construct CNN architectures are investigated and analyzed. First, two GA based methods are summarized. One is the optimization of CNN structures with the number and size of filters, connection between consecutive layers, and activation functions of each layer. The other is an new encoding method to represent complex convolutional layers in a fixed-length binary string, Second, CGP(Cartesian Genetic Programming) based method is surveyed for CNN structure optimization with highly functional modules, such as convolutional blocks and tensor concatenation, as the node functions in CGP. The comparison for three approaches is analysed and the outlook for the potential next steps is suggested.

• Journal of Life Science
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• v.19 no.6
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• pp.711-719
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• 2009

We determined a portion of mitochondrial 16S rRNA gene sequences (416 bp) to investigate the genetic structure of the octopus (Octopus minor Ssaki) population in Korea and China. Samples were obtained from Korea (Yeosu, Namhae, Jindo, Muan, Geomundo and Seosan) and China (Sandong) during the period of August 2006 to September 2007. Sequence analyses of 28 individual specimens collected from 7 localities revealed 11 haplotypes, ranging in a sequence divergence of 0.2% - 1.2%. Phylogenetic analyses using PHYLIP and networks subdivided the octopus into two clades (termed clade A and B) and the nucleotide divergence between them was 0.4%. This haplotype subdivision was in accordance with geographic separation: one at Yeosu, Namhae, Muan and Jindo, and the other at Seosan, Geomundo and Sandong. On the basis of hierarchial genetic analysis, genetic distance between localities in Korea and China were also found, but a significant population differentiation was not shown in this study (p>0.05). Consequently, most of the octopus populations in Korea had considerable distribution due to the mitochondrial gene flow that resulted in a formation of a genetically homogenous structure, whereas some of the Korean and Chinese populations had different genetic structures. Gene flow among populations may be restricted due to impassable geographic barriers that promote genetic differentiation.

• Journal of Life Science
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• v.23 no.6
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• pp.728-735
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• 2013

Plantago asiatica (Plantaginaceae) is a wind-pollinated plant that grows mainly on fields in East Asia. Starch gel electrophoresis was used to investigate the allozyme diversity and population structure of 18 populations of this species. Although the plantain populations were isolated and patchily distributed, they maintained a high level of genetic diversity; the average percentage of polymorphic loci was 57.1%, the mean number of alleles per locus was 2.07, and the average heterozygosity for 18 populations was 0.201. The combination of a predominant wind-pollinated, mix-mating reproduction, large population sizes, high gene flow between subpopulations, and a propensity for high fecundity may explain the high level of genetic diversity within populations. A direct gradient in overall genetic diversity is associated with latitude. Genetic diversity of P. asiatica is markedly decreased from $35^{\circ}3^{\prime}$ to high latitude and decreased from $35^{\circ}3^{\prime}N$ to low latitude, whereas there does not show a longitudinal gradient in genetic diversity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.84-84
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• 2017

Eleutherococcus senticosus (Siberian ginseng) is an important medicinal tree found in Russian taiga, and northern regions of Korea, Japan, and China. In this study, we analyzed the genome-wide distribution of microsatellites in E. senticosus using developed SSR markers. A total of 711 clones from an SSR-enriched genomic DNA library were sequenced, of which 47 clones (6.6%) were redundant. Of the 664 independent clones, only 12 polymorphic SSR markers were obtained, which also revealed successful amplicons in E. senticosus accessions. Using the developed SSR markers, we estimated genetic diversity and population structure among 131 E. senticosus accessions in Korea and China. The number of alleles ranged from 2 to 11, with an average of 7.4 alleles. The mean values of observed heterozygosity ($H_O$) and expected heterozygosity ($H_E$) were 0.59 and 0.56, respectively. The average polymorphism information content (PIC) was 0.51 in all 131 E. senticosus accessions. E. senticosus accessions in Korea and China showed a close genetic similarity. Significantly low pairwise genetic divergence was observed between the two regions, suggesting a relatively narrow level of genetic basis among E. senticosus accessions. Our results not only provide molecular tools for genetic studies in E. senticosus but are also helpful for conservation and E. senticosus breeding programs.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.1
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• pp.80-87
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• 2010

The method of function synthesis is essential when we control the systems not known their characteristic, by predicting the function to satisfy a relation between input and output from the given pairs of input-output data. In general the most systems operate non-linearly, it is easy to come about problem is composed with combinations of parameter, constant, condition, and so on. Genetic programming is proposed by one of function synthesis methods. This is a search method of function tree to satisfy a relation between input and output, with appling genetic operation to function tree to convert function into tree structure. In this paper, we indicate problems of a function synthesis method by an existing genetic programming propose four type of new improved method. In other words, there are control of function tree growth, selection of local search method for early convergence, effective elimination of redundancy in function tree, and utilization of problem characteristic of object, for preventing function from complicating when the function tree is searched. In case of this improved method, we confirmed to obtain superior structure to function synthesis method by an existing genetic programming in a short period of time by means of computer simulation for the two-spirals problem.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.105-105
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• 2018

Finger millet, Eleusine coracana Gaertn., is more nutritious than other cereals and millets and widely cultivate in tropical regions of the world. However, status of its genetic diversity remained concealed due to lack of research work in this species. In recent years, microsatellites have become the most used markers for studying population genetic diversity. In present study, genetic diversity and structure of different populations of finger millet from Africa and South Asia was examined at molecular level using newly developed EST-Simple Sequence Repeat (EST-SSR) markers using a total of 1,927 ESTs of Eleusine coracana available in the NCBI database. In total, 46 primers produced 292 alleles in a size range of 100-500 bp and mean Polymorphism Information Content (PIC) and Marker Index (MI) were 0.372 and 1.04, respectively. 46 primers showed polymorphism and 21 primers were identified as having a PIC value above 0.5. Principal coordinates analysis and the dendrogram constructed out of combined data of both markers showed grouping of finger millet accessions to their respective area of collection. The 156 accessions was classified into four groups, such as three groups of Africa collection and one group of Asia. Results of present study can be useful in identifying diverse accessions and management of this plant resource. Moreover, the novel SSR markers developed can be utilized for various genetic analyses in this species in future.

• Journal of Mushroom
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• v.18 no.4
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• pp.323-330
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• 2020

Agaricus bisporus is an important edible mushroom that is used as a functional food. In this study, European A. bisporus strains were analyzed for genetic diversity, population structure, and genetic differentiation using simple sequence repeat (SSR) markers. European A. bisporus strains were divided into four groups by distance-based analysis and two subpopulations by model-based analysis. The SSR markers used in this study did not group European A. bisporus strains by geographical region or pileus color. Genetic diversity was high in Group 4 based on distance-based analysis and Pop. 2 based on model-based analysis. A. bisporus strains showed very low genetic differentiation. The results of this study can be used for breeding A. bisporus in the future.

• Fisheries and Aquatic Sciences
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• v.25 no.12
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• pp.601-618
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• 2022

The genus Semisulcospira is an economically and ecologically valuable freshwater resource. Among the species, Semisulcospira coreana, Semisulcospira forticosta and Semisulcospira tegulata are endemic to the Korean peninsula and Semisulcospira gottschei is widespread in Asia. Therefore, maintenance and conservation of wild populations of these snails are important. We investigated the genetic diversity and population structure of Semisulcospira based on the mitochondrial cytochrome c oxidase subunit I (COI), NADH dehydrogenase subunit 4 (ND4), and combined mitochondrial DNA (COI + ND4) sequences. All four species and various genetic makers showed a high level of haplotype diversity and a low level of nucleotide diversity. In addition, Fu's Fs and Tajima's D neutrality tests were performed to assess the variation in size among populations. Neutrality tests of the four species yielded negative Fu's Fs and Tajima's D values, except for populations with one haplotype. The minimum spanning network indicated a common haplotype for populations of S. coreana, S. tegulata and S. gottschei, whereas S. forticosta had a rare haplotype. Also, genetic differences and gene flows between populations were assessed by analysis of molecular variance and using the pairwise fixation index. Our findings provided insight into the degree of preservation of the species' genetic diversity and could be utilized to enhance the management of endemic species.