• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.23-32
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• 2007

The nature of genetic variation and diversity among the 65 multivoltine silkworm genotypes was evaluated for 16 post cocoon characters. The components of genetic variation revealed higher PCV (60.487%) and GCV (44.56%) for evenness (variation 1) followed by cohesion (PCV=55.38%, GCV=40.36%) and non-broken filament length (PCV=32.05%, GCV=31.28%). The higher heritability ($h^2$ in broad sense) was observed for boil-off loss (95.6%) followed by non-broken filament length (95.22%). The both genotypic and phenotypic correlation indicated significant positive correlation of filament length with non-broken filament length, silk recovery, raw silk, neatness, and low neatness; and negative correlation with denier, renditta and silk waste. The principal component analysis (PCA) revealed 75.381 % of total variance from the five principal components extracted. On the basis of Mahalonobis' $D^2$ values (Ward's minimum variance), the sixty-five multivoltine silkworm genotypes were classified in to 9 clusters with substantial inter and intra cluster distances. Number of genotypes included in different clusters varied from 3 to 17. The results indicated that the optimum distance obtained in cluster VII (15.059) along with higher cluster mean values especially for filament length, non broken filament length, renditta, silk recovery, silk waste, and raw silk emphasized the utilization of these genotypes in the conventional silkworm breeding programme for improvement of multivoltine silk fibre quality. The possibility of exploiting genetic variation in post cocoon traits for efficient breeding programme is discussed.

• Journal of the Korean Operations Research and Management Science Society
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• v.32 no.1
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• pp.61-75
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• 2007

The purpose of this paper is to develop a new group classification method based on genetic algorithm and to com-pare its prediction performance with those of existing methods in the area of bond rating. To serve this purpose, we conduct various experiments with pilot and general models. Specifically, we first conduct experiments employing two pilot models : the one searching for the cluster center of each group and the other one searching for both the cluster center and the attribute weights in order to maximize classification accuracy. The results from the pilot experiments show that the performance of the latter in terms of classification accuracy ratio is higher than that of the former which provides the rationale of searching for both the cluster center of each group and the attribute weights to improve classification accuracy. With this lesson in mind, we design two generalized models employing genetic algorithm : the one is to maximize the classification accuracy and the other one is to minimize the total misclassification cost. We compare the performance of these two models with those of existing statistical and artificial intelligent models such as MDA, ANN, and Decision Tree, and conclude that the genetic algorithm-based group classification method that we propose in this paper significantly outperforms the other methods in respect of classification accuracy ratio as well as misclassification cost.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.230-235
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• 2013

Amaranths (Amaranthus sp.), an endemic American crop, are now grown widely across the world. This study used 14 simple sequence repeat (SSR) markers to analyze the genetic diversity of 74 amaranth accessions from the United States, with eight accessions from Australia as controls. One hundred twenty-two alleles, averaging eight alleles per locus, were observed. The average major allele frequency, expected heterozygosity, and polymorphism information content (PIC) were 0.44, 0.69, and 0.65, respectively. The structure analysis based on genetic distance classified 77 accessions (94%) into three clusters, while five accessions (6%) were admixtures. Among the three clusters, Cluster 3 had the highest allele number and PIC values, while Cluster 2 had the lowest. The lowest FST was between Clusters 1 and 3, indicating that these two clusters have higher gene flow between them compared to the others. This finding was reasonable because Cluster 2 included most of the Australian accessions. These results indicated satisfactory genetic diversity among U.S. amaranths. These findings can be used to design effective breeding programs involving different plant characteristics.

• Development and Reproduction
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• v.26 no.2
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• pp.91-98
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• 2022

Genomic DNA (gDNA) set apart from two populations of Korean Charybdis crab (Charybdis japonica) was augmented by PCR experiments. The five oligonucleotides primers (ONT-primers) were spent to yield the number of unique loci shared to each crab population (ULSECP) and number of loci shared by the two crab populations (LSTCP). 305 fragments (FRAGs) were identified in the Charybdis crab population A (CCPA), and 344 in the Charybdis crab population B (CCPB): 44 number of ULSECP (14.43%) in the CCPA and 110 (31.98%) in the CCPB. 44 number of LSTCP, with an average of 8.8 per primer, were detected in the two crab populations. The bandsharing (BS) value between entity's no. 01 and no. 10 was the lowest (0.371) between the two CCPs. The average bandsharing (ABS) values of individuals in the CCPA (0.575±0.014) were lesser than in those originated from the CCPB (0.705±0.011) (p < 0.05). The polar hierarchical dendrogram (PHD) achieved by the five ONT-primers denotes three genetic clusters (GCs): cluster I (CHARYBCRAB 01, 04, 05, 06, and 08), cluster II (CHARYBCRAB 02, 03, 07, 09, 10, and 11) and cluster III (CHARYBCRAB 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, and 22). The shortest genetic distance (GD) displaying significant molecular difference (MD) was between individuals CHARYBCRAB no. 18 and CHARYBCRAB no. 17 (0.055).

• Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.151-160
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• 2005

Genomic DNA samples isolated from Fenneropenaeus chinensis (fleshy prawn; FP) and Palaemon gravieri (Chinese ditch prawn; CDP) collected in the West Sea, off the Korean Peninsula, at Buan, were PCR-amplified repeatedly. The sizes of the DNA fragments generated by seven different primers varied from 50 bp to 1,600 bp. We identified 358 fragments for the FP species and 301 fragments for the CDP species. There were 18 polymorphic fragments (5.03$\%$) for the FP species and 12 (3.99$\%$) for the CDP species. In total, 66 common fragments (average of 9.4 fragments per primer) were observed for the FP species and 44 fragments (average of 6.3 fragments per primer) were observed for the CDP species. The numbers of specific fragments seen for the FP species and CDP species were 38 and 47, respectively. The complexity of the banding patterns varied dramatically between the primers and the two species. In the FP species, a specific fragment of approximately 1,200 bp generated by primer OPB-04 exhibited inter-individual-specific characteristics that were indicative of DNA polymorphisms. Moreover, in the CDP species, a major fragment of approximately 550 bp generated by primer OPB-20 was found to be specific for the CDP. The average bandsharing value between the two prawn species was 0.421$\pm$0.006, and ranged from 0.230 to 0.611. The dendrogram obtained using the data from the seven primers indicated seven genetic clusters: cluster 1, FLESHY 01, 02, 03, and 04; cluster 2, FLESHY 05, 06, and 07; cluster 3, FLESHY 08, 09, 10, and 11; cluster 4, DITCH 13, 14, 16, and 18; cluster 5, DITCH 12, 15, and 17; cluster 6, DITCH 19, 20, and 21; and cluster 7, DITCH 22. The genetic distance between the two prawn species ranged from 0.071 to 0.642. Thus, RAPD-PCR analysis revealed a significant genetic distance between the two prawn species. Using various arbitrary primers, RAPD-PCR may be applied to identify specific/polymorphic markers that are particular to a species and geographic population, and to define genetic diversity, polymorphisms, and similarities among shrimp species.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1996.10a
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• pp.290-293
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• 1996

This paper proposes a scheme of initial cluster center selection in FCM algorithm using the genetic algorithms. The FCM algorithm often fails in the search for global optimum because it is local search techniques that search for the optimum by using hill-climbing procedures. To solve this problem, we search for a hypersphere encircling each clusters whose parameters are estimated by the genetic algorithms. Then instead of a randomized initialization for fuzzy partition matrix in FCM algorithm, we initialize each cluster center by the center of a searched hypersphere. Our experimental results show that the proposed initializing scheme has higher probabilities of finding the global or near global optimal solutions than the traditional FCM algorithm.

• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.716-720
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• 2006

The genetic diversity among the genus Viola was evaluated using the random amplified polymorphic DNA (RAPD) method. A total of 142 distinct amplification fragments by 18 random primers were scored to perform the cluster analysis with UPGMA. Viola species from the subsection Patellares were clustered into group I to IV. The groups from I to IV were consistent with its morphological taxonomy, series Pinnatae, Chinensis, Variegatae, and Patellares in the subsection Patellares, respectively. Even though V. albida and V. albida var. takahasii were classified in Chinensis, they were assigned into group I. The cluster analysis separated other subsections from Patellares in the section Nomimium. Interestingly, V. verecunda and V. grypoceras in subsections Biobatae and Trigonocarpae, respectively, were clustered into group C with a high similarity coefficient. Therefore, RAPD analysis can be used for providing an alternative classification system to identify genotypes and morphological characters of Viola species.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.40-47
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• 2000

One of the drawbacks of GA-based structural optimization is that the fitness evaluation of a population of hundreds of individuals requiring hundreds of structural analyses at each CA generation is computational too expensive. Therefore, a parallel genetic algorithm is developed for structural optimization on a cluster of personal computers in this paper. Based on the parallel genetic algorithm, a population at every generation is partitioned into a number of sub-populations equal to the number of slave computers. Parallelism is exploited at sub-population level by allocationg each sub-population to a slave computer. Thus, fitness of a population at each generation can be concurrently evaluated on a cluster of personal computers. For implementation of the algorithm a virtual distributed computing system in a collection of personal computers connected via a 100 Mb/s Ethernet LAN. The algorithm is applied to the minimum weight design of a steel structure. The results show that the computational time requied for serial GA-based structural optimization process is drastically reduced.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1570-1579
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• 2019

The fungal products dibenzodioxocinones promise a novel class of inhibitors against cholesterol ester transfer protein (CEPT). Knowledge as to their biosynthesis is scarce. In this report, we characterized four more dibenzodioxocinones, which along with a previously described member pestalotiollide B, delimit the dominant spectrum of secondary metabolites in P. microspora. Through mRNA-seq profiling in $g{\alpha}1{\Delta}$, a process that halts the production of the dibenzodioxocinones, a gene cluster harboring 21 genes including a polyketide synthase, designated as pks8, was defined. Disruption of genes in the cluster led to loss of the compounds, concluding the anticipated role in the biosynthesis of the chemicals. The biosynthetic route to dibenzodioxocinones was temporarily speculated. This study reveals the genetic basis underlying the biosynthesis of dibenzodioxocinone in fungi, and may facilitate the practice for yield improvement in the drug development arena.

• Plant Resources
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• v.6 no.3
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• pp.195-204
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• 2003

Genetic diversity of 45 tea accessions from Korea, Japan, China and Taiwan was investigated by using RAPD analysis. Out of the eighty primers screened, twenty primers generated 99 polymorphic bands with a polymorphic rate 87.0%. The size of the amplified fragments ranged from about 3,138 bp to 520 bp. By cluster analysis, all of the 45 accessions can be grouped into five groups. Over 90% of the 32 Korean accessions belonged to group II, III, IV and V. Moreover, newly developed Korean cultivars (accession no. 13, 14 and 15) belonged to very different group compared with any other Korean accessions. Among the Korean accessions, the minimum genetic similarity 0.500 was obtained between accession no. 17 and 37 and the largest genetic similarity 0.912 between no. 20 and 21.