• Title/Summary/Keyword: k-d tree

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Genetic Characterization of Indigenous Goats of Sub-saharan Africa Using Microsatellite DNA Markers

  • Chenyambuga, S.W.;Hanotte, O.;Hirbo, J.;Watts, P.C.;Kemp, S.J.;Kifaro, G.C.;Gwakisa, P.S.;Petersen, P.H.;Rege, J.E.O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.4
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    • pp.445-452
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    • 2004
  • Genetic diversity of sub-Saharan African goats was assessed using 19 microsatellite markers. Breeds were sampled from eastern Africa (Maasai, Kigezi, Mubende, North West Highland, Arsi-Bale), southern Africa (Ndebele, Pafuri) and West Africa (West African Dwarf, Maure, Djallonke). European breeds (Grisons Striped, Toggenburg), Asian breeds (Mongolian Cashmere, Bandipur) and a Middle East breed (Arab) were also included. The mean number of alleles per locus and average gene diversity ranged from 5.26$\pm$0.464 (Djallonke) to 7.05$\pm$0.516 (Mubende) and from 0.542$\pm$0.036 (Pafuri) to 0.672$\pm$0.031 (Ndebele), respectively. The between breeds variation evaluated using $$G_{ST}$$ and $\theta$ were found to account for 14.6% ($\theta$) and 15.7% ($$G_{ST}$$) of the total genetic variation. The $D_{A}$ measure of genetic distance between pairs of breeds indicated that the largest genetic distance was between Pafuri and Djallonke while the lowest genetic distance was between Arsi-Bale and North West Highland. A neighbour-joining tree of breed relationships revealed that the breeds were grouped according to their geographic origins. Principal component analysis supported the grouping of the breeds according to their geographic origins. It was concluded that the relationships of sub-Saharan African goat breeds were according to their geographical locations implying that the goats of eastern Africa, West Africa and southern Africa are genetically distinct. Within each sub-region, goat populations could be differentiated according to morphological characteristics.

A study on the safety improvement of above ground membrane LNG storage tank (상지상식 멤브레인 액화천연가스 저장탱크의 안전성 향상 방안)

  • Lee, Seung Rim;Kim, Han Sang
    • Journal of Energy Engineering
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    • v.21 no.4
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    • pp.339-345
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    • 2012
  • RMembrane LNG storage tanks have been recently investigated to replace full-containment LNG storage tanks because of safety and cost aspects. Quantitative Risk Analysis (QRA) and Finite Element Method (FEM) were used to evaluate safety of membrane LNG storage tanks. In this study, structural safety evaluation results via FEM analysis showed that both membrane type and full-containment type cryogenic LNG storage tanks with 140,000 $m^3$ capacity were equivalently safe in terms of strength safety and leakage safety of a storage tank system. Also, Fault Tree Analysis (FTA) was used to improve the safety of membrane LNG storage tanks and membrane LNG tanks were modified by adding three safety equipments: impact absorber structure for the low part of the membrane, the secondary barrier to diminish the thermal stress of the corner part of the outer tank, and a pump catcher in case of falling of a pump. Consequently, the safety of the modified membrane LNG storage tanks were proved to be equivalent to that of full-containment LNG storage tanks.

Application of RAPD Markers to Early Selection of Elite Individuals of Pinus Species for a Clonal Forest Tree Breeding Program (소나무류 육종에 있어 임의 증폭 다형 디엔에이(RAPD)지표를 이용한 우량 임목의 조기 선발)

  • Yi, Jae-Seon;Cheong, Eun-Ju;Moon, Heung-Kyu;Dale, Glenn T.;Teasdale, Robert D.
    • Journal of Forest and Environmental Science
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    • v.11 no.1
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    • pp.81-101
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    • 1995
  • Random amplified polymorphic DNA (RAPD) technology, a recent approach in molecular genetics, is much usable to select the elite trees and to maximize the genetic gain in forest tree breeding program, providing a clue to determine the genetic marker-trait correlation. This review intorduces research on bark thickness and breeding strategy in Pinus elliottii, Pinus caribaea and their hybrid by Queensland Forest Service and ForBio Research Pty Ltd, University of Queensland, which employ RAPD technology. Genetic linkage map of $F_1$ hybrids includes 186 RAPD markers and 16 linkage groups (1641 cM long in total) and 6 quantitative trait loci are located putatively for bark thickness. Following recent research results and experiences in pine breeding programs, the forseeable stages in the application and development are proposed for marker assisted selectin; stage 1-determination of species specific markers for genes controlling traits of commercial interest, and stage 2-determination of marker-allele association for specific allelic variants within pure species. As pines inherit their megagametophytes from the seed parent and zygotic embryos from both male and female parents, the determination of marker-trait correlation is possible even in embryo stage, eventually making ways for the early selection of elite individuals.

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Hepatic Vessel Segmentation using Edge Detection (Edge Detection을 이용한 간 혈관 추출)

  • Seo, Jeong-Joo;Park, Jong-Won
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.3
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    • pp.51-57
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    • 2012
  • Hepatic vessel tree is the key structure for hepatic disease diagnosis and liver surgery planning. Especially, it is used to evaluate the donors' and recipients' liver for the LDLT(Living Donors Liver Transplantation) and estimate the volumes of left and right hepatic lobes for securing their life in the LDLT. In this study, we propose a method to apply canny edge detection that is not affected by noise to the liver images for automatic segmentation of hepatic vessels tree in contrast abdominal MDCT image. Using histograms and average pixel values of the various liver CT images, optimized parameters of the Canny algorithm are determined. It is more time-efficient to use the common parameters than to change parameters manually according to CT images. Candidates of hepatic vessels are extracted by threshold filtering around the detected the vessel edge. Finally, using a system which detects the true-negatives and the false-positives in horizontal and vertical direction, the true-negatives are added in candidate of hepatic vessels and the false-positives are removed. As a result of the process, the various hepatic vessel trees of patients are accurately reconstructed in 3D.

Evaluation of DNA Markers for Fruit-related Traits and Genetic Relationships Based on Simple Sequence Repeat in Watermelon Accessions

  • Jin, Bingkui;Park, Girim;Choi, Youngmi;Nho, Jaejong;Son, Beunggu;Park, Younghoon
    • Horticultural Science & Technology
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    • v.35 no.1
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    • pp.108-120
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    • 2017
  • Modern watermelon cultivars (Citrullus lanatus [Thunb.] Matsum.& Nakai var. lanatus) have fruits with diverse phenotypes, including fruit shape, rind patterns, and flesh color. Molecular markers enable efficient selection of plants harboring desirable phenotypes. In the present study, publicly available DNA markers tightly linked to fruit shape, rind stripe pattern, and flesh color were evaluated using 85 watermelon accessions with diverse fruit phenotypes. For fruit shape, the dCAPS SUN - Cla011257 marker revealed an 81% of marker - trait match for accessions with elongated or round fruits. For rind stripe pattern, the SCAR wsb6-11marker was effective for selecting Jubilee-type rind pattern from other rind patterns. For flesh color, the Clcyb.600 and Lcyb markers derived from a mutation in the Lycopene ${\beta}$ - cyclase (Lcyb) gene, were effective at selecting red or yellow flesh. Forty-eight accessions possessing diverse fruit - related traits were selected as a reference array and their genetic relationships assessed using 16 SSR markers. At a coefficient of 0.11, the 48 accessions grouped into two major clades: Clade I and Clade II. Clade I subdivided further into subclades I - 1 and I - 2 at a coefficient of 0.39. All accessions with colored flesh were classified into Clade I, whereas those with white - flesh were classified into Clade II. Differences in fruit traits between subclades I - 1 and I - 2 were observed for rind pattern and fruit color; a majority of the accessions with Crimson-type striped or non-striped rind were grouped together in subclade I - 1, while most accessions in subclade I - 2 had a Jubilee - type rind stripe pattern. These results imply that reference array watermelon accessions possess distinguishable genetic structure based on rind stripe pattern. However, no significant grouping pattern was observed based on other fruit-related traits.

Genetic Diversity and Molecular Markers in Introduced and Thai Native Apple Snails (Pomacea and Pila)

  • Thaewnon-Ngiw, Bungorn;Klinbunga, Sirawut;Phanwichien, Kantimanee;Sangduen, Nitsri;Lauhachinda, Nitaya;Menasveta, Piamsak
    • BMB Reports
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    • v.37 no.4
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    • pp.493-502
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    • 2004
  • The genetic diversity and species-diagnostic markers in the introduced apple snail, Pomacea canaliculata and in the native Thai apple snails; Pila ampullacea, P. angelica, P. pesmei, and P. polita, were investigated by restriction analysis of COI and are reported for the first time. Twenty-one composite haplotypes showing non-overlapping distributions among species were found. Genetic heterogeneity analysis indicated significant differences between species (P < 0.0001) and within P. pesmei (P < 0.0001) and P. angelica (P < 0.0004). No such heterogeneity was observed in Pomacea canaliculata (P > 0.0036 as modified by the Bonferroni procedure), P. ampullacea (P = 0.0824-1.000) and P. polita (P = 1.0000). A neighbor-joining tree based on genetic distance between pairs of composite haplotypes differentiated all species and indicated that P. angelica and P. pesmei are closely related phylogenetically. In addition, the 16S rDNA of these species was cloned and sequenced. A species-specific PCR for P. canaliculata was successfully developed with a sensitivity of detection of approximately 50 pg of the target DNA template. The amplification of genomic DNA (50 pg and 25 ng) isolated from the fertilized eggs, and juveniles (1, 7, and 15 d after hatching) of Pomacea canaliculata was also successful, and suggested that Pomacea canaliculata and Pila species can be discriminated from the early stages of development.

An Empirical Model for the Prediction of the Onset of Upward-Movement of Overwintered Caccopsylla pyricola (Homoptera: Psyllidae) in Pear Orchards (배과원에서 꼬마배나무이 월동성충의 수상 이동시기 예측 모형)

  • Kim, Dong-Soon;Yang, Chang-Yeol;Jeon, Heung-Yong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.4
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    • pp.228-233
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    • 2007
  • Pear psylla, Caccopsylla pyricola (Homoptera: Psyllidae), is a serious insect pest in pear orchards. C. pyricola overwinters as adults under rough bark scales of pear trees. When the weather warms up in the spring, the overwintered adults become active, climb up to the tree branches, and inhabit on fruit twigs to lay eggs. This study was conducted to develop a forecasting model for the onset of upward-movement of overwintered C. pyricola adults to control them by timely spraying of petroleum oil. The adult population densities were observed under rough barks (B) and on fruit twigs (T) of pear trees. Relative upward-movement rates (R) were calculated as T/(B+T). Low threshold temperatures for the activation of overwintered C. pyricola adults were selected arbitrarily from 5 to $9^{\circ}C$ at a $1^{\circ}C$ interval. Then, the days (D) when daily maximum air temperatures were above each low threshold temperature were counted from 1 February until to the dates with R $\geq$ 0.8. The same methods were applied for the prediction of the first observation of eggs. The variation of coefficients (CV) for the mean Des were lowest with the low threshold temperature of $6^{\circ}C$. At this selected threshold temperature, the upward movement of C. pyricola adults occurred with 12 D and they started laying eggs with 25 D. In the field validation, the model outputs with the $6^{\circ}C$ threshold temperature reasonably well explained the observed data in Suwon and Cheonan in 2002. Practical usages of the model were also discussed.

Degradation of Cyanide by Activated Sludge Immobilized with Polyethylene Glycol (고정화 활성슬러지를 이용한 시안 분해)

  • Cheong, Kyung-Hoon;Choi, Hyung-Il;Kim, Jung-Ae;Moon, Ok-Ran;Kim, Myung-Hee
    • Journal of Environmental Science International
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    • v.17 no.12
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    • pp.1343-1351
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    • 2008
  • The activated sludge obtained from wastewater coke oven plant was immobilized by entrapment with polyethylene glycol (PEG). The effects of several factors on the biodegradation of $CN^-$ from. synthetic wastewater were investigated using batch and continuous reactors. The degradation rate of $CN^-$ increased with increasing of the immobilized bead volume in the reactor. Approximately 7.65mg/L of $NH_4-N$ was produced upon the degradation of 35mg/L of $CN^-$. When high concentrations of the toxic cyanide complex were used in the testing of cyanide degradation, the free activated sludge could be inhibited more than that of the immobilized activated sludge. When the phenol concentration was higher than 400mg/L in the synthetic wastewater, approximately 98.4% of $CN^-$ was removed within 42 hours by the immobilized activated sludge. However, the cyanide was not completely degraded by the tree activated sludge. This indicates that high phenol concentrations can act as a toxic factor for the free activated sludge. A $CN^-$ concentration of less than 1mg/L was achieved by the immobilized sludge at the loading rate of 0.025kg $CN^-/m^3-d$. Moreover, it was found that the HRT should be kept for 48 hours in order to obtain stable treatment conditions.

Dependency-based Framework of Combining Multiple Experts for Recognizing Unconstrained Handwritten Numerals (무제약 필기 숫자를 인식하기 위한 다수 인식기를 결합하는 의존관계 기반의 프레임워크)

  • Kang, Hee-Joong;Lee, Seong-Whan
    • Journal of KIISE:Software and Applications
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    • v.27 no.8
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    • pp.855-863
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    • 2000
  • Although Behavior-Knowledge Space (BKS) method, one of well known decision combination methods, does not need any assumptions in combining the multiple experts, it should theoretically build exponential storage spaces for storing and managing jointly observed K decisions from K experts. That is, combining K experts needs a (K+1)st-order probability distribution. However, it is well known that the distribution becomes unmanageable in storing and estimating, even for a small K. In order to overcome such weakness, it has been studied to decompose a probability distribution into a number of component distributions and to approximate the distribution with a product of the component distributions. One of such previous works is to apply a conditional independence assumption to the distribution. Another work is to approximate the distribution with a product of only first-order tree dependencies or second-order distributions as shown in [1]. In this paper, higher order dependency than the first-order is considered in approximating the distribution and a dependency-based framework is proposed to optimally approximate the (K+1)st-order probability distribution with a product set of dth-order dependencies where ($1{\le}d{\le}K$), and to combine multiple experts based on the product set using the Bayesian formalism. This framework was experimented and evaluated with a standardized CENPARMI data base.

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A Comparative Study on the Types of Vascular Bundle Sheath of Sasa with Those of Bambusa (Sasa와 Bambusa속(屬)의 유관속초형(維管束鞘型)에 의(依)한 비교연구(比較硏究))

  • Kim, Jai-Saing
    • Journal of Korean Society of Forest Science
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    • v.39 no.1
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    • pp.35-46
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    • 1978
  • The morphological characteristics of vascular bundle sheath occurring on the culm wall were investigated by using many species of Bambusa and Sasa in order to test new classification method for endomorphological charateristics of Bamboos. The results obtained were as follows. 1. As for the thickness of the culm wall in the culm, it was shown that the culm wall of the Bambusa becomes thinner in propertion to its nearness to the upper part of the tree, but no distinctive difference appeared in the Sasa. 2. It was shown that many species of Bambusa has a, b types but the Sasa had a' type and had a, b types. 3. It was shown that many species of Bambusa had e', h, and i types but the Sasa had not them and both of species had not f type. 4. It was shown that many species of Bambusa had c, d, e, and g types, but the Sasa had c, d, and e types and had not g type. 5. In the classification of Bambusa and Sasa, The method of the physiological classification was more effective than test of external observation, and it will encourage further study.

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