• The Korean Journal of Zoology
• /
• v.31 no.3
• /
• pp.218-224
• /
• 1988

Restriction endonucleases were used to search for intraspecific variation at 32 cleavage sites in mitochondrial DNA(mtDNA) purified from fourteen strains of Drosophila melanogaster helonging to different localities of the world. mtDNA of D. melanogaster was displayed site variation(Hpall, Haelll and Seal endonucleases) and length variation(maxirnum 550bp). Six genotypes, Ml, M2, M3, M4, M6 and M7, could be distinguished based on ihe site types witti a low average of intraspecific substitution rate (1.88%),but M5 type of Ogasawara strain in Japan was not detected in this study. A possible explanation for the low divergence was that mtDNA variation of fourteen strains in D. melanogaster could not he accumulated sufficiently owing to recent divergence of few individuals, and that sequence divergence was prevented by frequent migration in spite of the geographical isolation.

• ETRI Journal
• /
• v.39 no.1
• /
• pp.21-29
• /
• 2017

This paper addresses the problem of unsupervised speech separation based on robust non-negative matrix factorization (RNMF) with ${\beta}$-divergence, when neither speech nor noise training data is available beforehand. We propose a robust version of non-negative matrix factorization, inspired by the recently developed sparse and low-rank decomposition, in which the data matrix is decomposed into the sum of a low-rank matrix and a sparse matrix. Efficient multiplicative update rules to minimize the ${\beta}$-divergence-based cost function are derived. A convolutional extension of the proposed algorithm is also proposed, which considers the time dependency of the non-negative noise bases. Experimental speech separation results show that the proposed convolutional RNMF successfully separates the repeating time-varying spectral structures from the magnitude spectrum of the mixture, and does so without any prior training.

• Journal of Internet Computing and Services
• /
• v.13 no.1
• /
• pp.1-6
• /
• 2012

In the paper, an information divergence called Kullback-Leiber divergence, which measures the average of the logarithmic difference between two probability density functions, is utilized to derive a novel method for spectrum sensing in cognitive radio systems. In the proposed sensing method, we test whether the observed samples are drawn from the noise distribution by using Kullback-Leiber divergence. It is shown by numerical results that under the same conditions, the proposed Kullback-Leiber divergence-based spectrum sensing always outperforms the energy detection based spectrum sensing significantly, especially in low SNR regime and in fading circumstance.

• Journal of Korean Ophthalmic Optics Society
• /
• v.14 no.4
• /
• pp.53-57
• /
• 2009

Purpose: To study the relationship of N.P.C, heterophoria and near convergence and divergence by amount of the refractive error. Methods: All subjects have no ocular disease and their mean age is 22.7. All 39 subjects examined about refractive error, near point of convergence (NPC), heterophoria, near convergence and divergence. Results: Classified by low refractive state, middle refractive state, and high refractive state compared with the expected value of Morgan. NPC had been measured within low and middle refractive state eight all the 8cm. However, high refractive state measured 9.64 cm. Low and middle refractive state for the classification by near phoria. Near esophoria groups was smallest by near divergence and exophoria groups was smallest by near convergence. Conclusions: Near convergence were largest with esophoria while near divergence were largest with exophoria.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.24 no.1
• /
• pp.41-47
• /
• 2012

The Scarites aterrimus (Coleoptera: Carabidae) dwells exclusively on coastal sandy dunes. Previously, we investigated the nation-wide magnitude and nature of genetic diversity of the species using mitochondrial COI gene and found moderate to low magnitude of sequence diversity, the presence of closely related haplotypes, and relatively high gene flow estimate. Based on these observations we concluded that the species had no historical barriers that bolster genetic subdivision and possible population decline. In this study, we additionally sequenced mitochondrial COII gene from 23 individuals collected from 9 Korean localities to confirm previous findings. Sequencing of 688 bp COII gene provided 5 haplotypes ranging in sequence divergence from 0.145% to 0.291% (1 ~ 2 bp), further confirming low sequence divergence of the species. Gene flow estimates and genetic diversity estimates also support the previous findings that there had been no historical barriers that bolster genetic subdivision.

• Journal of applied mathematics & informatics
• /
• v.20 no.1_2
• /
• pp.611-621
• /
• 2006

This paper is to discuss the numerical conformal mapping from the unit disk onto Jordan region, which can be solved by Theodorsen equation. Wegmann's method has been known as the most efficient one for the Theodorsen equation. However, we found divergence through numerical experiments by the iterative method of Wegmann. The divergence occurs especially when some degree of difficulty is high. We analyze the cause of divergence and propose an improved method by applying a low frequency pass filter to Wegmann's method. By this proposed method we can get a stable convergence for all the problems which was unstable with the Wegmann's method.

• Journal of Aquaculture
• /
• v.18 no.4
• /
• pp.252-259
• /
• 2005

Isozyme and AFLP analyses were examined to estimate the utilities of them as a genetic marker. The utilities were evaluated by genetic divergence and relationships among the four distinct abalone species; Haliotis discus hannai collected from northeast coast of Japan and Yellow-Sea coast of China, H. rufescens collected from west coast of USA, H rubra collected from southeast coast of Australia and H midae collected from Cape Town of South Africa. Isozyme and AFLP analyses showed a clear genetic divergence between every pair of species. Genetic relationships among the low species estimated by isozyme and AFLP analyses reflected to geographical distribution and morphological characteristics. In conclusion, Isozyme and AFLP analyses are suitable genetic markers far estimates of genetic divergence and relationship among abalone species.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.821-824
• /
• 2009

Conformal mapping is useful to solve problems in physics, engineering and so on. This paper is to discuss the numerical conformal mapping from the unit disk onto Jordan region, which can be solved by Theodorsen equation. Wegmann's method has been known as the most efficient one for the Theodorsen equation. However, we found divergence through numerical experiments by the iterative method of Wegmann. The divergence occurs especially when some degree of difficulty is high. We analyze the cause of divergence and propose an improved method by applying a low frequency pass filter to Wegmann's method. By this proposed method we can get a stable convergence for all the problems which was unstable with the Wegmann's method.

• Korean Journal of Optics and Photonics
• /
• v.8 no.4
• /
• pp.297-302
• /
• 1997

A hemiconfocal resonator equipped with an intra-cavity adjustable aperture and a beam splitter has been studied experimentally to achieve a controlled low beam divergence operation in a vapor laser system. The dependences of output characteristics both on the aperture diameter and on the angle of beam splitter have been investigated. By adjusting the aperture diameter from 14mm to 2mm to 2mm, we were able to reduce the beam divergence from 3.1 mrad to 0.25 mrad and achieved the 8-times increase in the far-field power density.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.3
• /
• pp.315-319
• /
• 2003

Random amplified polymorphic DNA (RAPD) analysis was done with 19 oligonucleotide primers to study genetic similarities and divergence among different types of Deoni breed of cattle viz., Balankya, Wannera and Waghya. Six random primers produced low to high numbers of polymorphic bands between pooled DNA of different Deoni types. Of the 48 RAPD markers obtained 33 were common to all Deoni types, 3 were individual specific and 12 were polymorphic for different Deoni types. The mean average percentage difference values among Deoni types showed that Balankya and Wannera had less genetic divergence when compared to Waghya.