• Title/Summary/Keyword: Multiple trees

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Binary Forecast of Asian Dust Days over South Korea in the Winter Season (남한지역 겨울철 황사출현일수에 대한 범주 예측모형 개발)

  • Sohn, Keon-Tae;Lee, Hyo-Jin;Kim, Seung-Bum
    • The Korean Journal of Applied Statistics
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    • v.24 no.3
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    • pp.535-546
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    • 2011
  • This study develops statistical models for the binary forecast of Asian dust days over South Korea in the winter season. For this study, we used three kinds of data; the rst one is the observed Asian dust days for a period of 31 years (1980 to 2010) as target values, the second one is four meteorological factors(near surface temperature, precipitation, snowfall, ground wind speed) in the source regions of Asian dust based on the NCEP reanalysis data and the third one is the large-scale climate indices. Four kinds of statistical models(multiple regression models, logistic regression models, decision trees, and support vector machines) are applied and compared based on skill scores(hit rate, probability of detection and false alarm rate).

Classification of Viruses Based on the Amino Acid Sequences of Viral Polymerases (바이러스 핵산중합효소의 아미노산 서열에 의한 바이러스 분류)

  • Nam, Ji-Hyun;Lee, Dong-Hun;Lee, Keon-Myung;Lee, Chan-Hee
    • Korean Journal of Microbiology
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    • v.43 no.4
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    • pp.285-291
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    • 2007
  • According to the Baltimore Scheme, viruses are classified into 6 main classes based on their replication and coding strategies. Except for some small DNA viruses, most viruses code for their own polymerases: DNA-dependent DNA, RNA-dependent RNA and RNA-dependent DNA polymerases, all of which contain 4 common motifs. We undertook a phylogenetic study to establish the relationship between the Baltimore Scheme and viral polymerases. Amino acid sequence data sets of viral polymerases were taken from NCBI GenBank, and a multiple alignment was performed with CLUSTAL X program. Phylogenetic trees of viral polymerases constructed from the distance matrices were generally consistent with Baltimore Scheme with some minor exceptions. Interestingly, negative RNA viruses (Class V) could be further divided into 2 subgroups with segmented and non-segmented genomes. Thus, Baltimore Scheme for viral taxonomy could be supported by phylogenetic analysis based on the amino acid sequences of viral polymerases.

Comparing Two Mycobacterium tuberculosis Genomes from Chinese Immigrants with Native Genomes Using Mauve Alignments

  • Ryoo, Sungweon;Lee, Jeongsoo;Oh, Jee Youn;Kim, Byeong Ki;Kim, Young;Kim, Je Hyeong;Shin, Chol;Lee, Seung Heon
    • Tuberculosis and Respiratory Diseases
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    • v.81 no.3
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    • pp.216-221
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    • 2018
  • Background: The number of immigrants with tuberculosis (TB) increases each year in South Korea. Determining the transmission dynamics based on whole genome sequencing (WGS) to cluster the strains has been challenging. Methods: WGS, annotation refinement, and orthology assignment for the GenBank accession number acquisition were performed on two clinical isolates from Chinese immigrants. In addition, the genomes of the two isolates were compared with the genomes of Mycobacterium tuberculosis isolates, from two native Korean and five native Chinese individuals using a phylogenetic topology tree based on the Multiple Alignment of Conserved Genomic Sequence with Rearrangements (Mauve) package. Results: The newly assigned accession numbers for two clinical isolates were CP020381.2 (a Korean-Chinese from Yanbian Province) and CP022014.1 (a Chinese from Shandong Province), respectively. Mauve alignment classified all nine TB isolates into a discriminative collinear set with matched regions. The phylogenetic analysis revealed a rooted phylogenetic tree grouping the nine strains into two lineages: strains from Chinese individuals and strains from Korean individuals. Conclusion: Phylogenetic trees based on the Mauve alignments were supposed to be useful in revealing the dynamics of TB transmission from immigrants in South Korea, which can provide valuable information for scaling up the TB screening policy for immigrants.

Effects of Soil Environment on the Growth of Pinus Thunbergii and Zelkova Serrata at the Reclaimed Seaside (임해매립지의 토양환경이 곰솔과 느티나무의 생육에 미치는 영향)

  • 김도균;장병문;김용식
    • Journal of the Korean Institute of Landscape Architecture
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    • v.28 no.4
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    • pp.9-20
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    • 2000
  • The purpose of thus paper is to provide the knowledge on preparing for the planting soil and planting method, and maintenance at the reclaimed seaside. Based on the collected data from the field work, the soil environment, the growth of height, inter-node, tree ring and roots of the two species had been analyzed. The determinant of soil factors, affecting the growth of trees, turned out to be six elements such as soil hardness, soil acidity, potassium, calcium, magnesium and total nitrogen. Because the variances of both growth of tree height and tree ring are greater than that of root, the growth characteristics of ground parts of the species by the individual tree species is more dynamical than those of underground parts. From the mean difference test the growth of height, root between Pinus thunbergii and Zelkova serrata, have been turned out to be statistically significant at 5 percent level. Pinus thunbergii is a sapling, so it grows faster than Zelkova serrata while Pinus thunbergii has better roots system than Zelkova serrata. From the correlation analysis, it showed the very strong correlation between tree height growth and potassim, while the lowest correlation coefficient was between soil hardness and potassim as 0.744. From the multiple regression analysis, both soil hardness and magnesium affect to the tree growth, soil hardness and potassium to the tree growth, potassium and calcium to the rot growth, respectively. Using this research results, we can be use the planting plan including revegetation, construction and maintenance of the reclaimed seaside. In the future, the planting method including the ground preparation and tree species selection for the reclaimed seaside should be accompanied in advanced through the soil survey and relevant analysis.

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A Network-based Indexing Method for Trajectories of Moving Objects on Roads (도로 위에 존재하는 이동객체의 궤적에 대한 네트워크 기반의 색인 방법)

  • Kim, Kyoung-Sook;Li, Ki-Joune
    • The KIPS Transactions:PartD
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    • v.13D no.7 s.110
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    • pp.879-888
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    • 2006
  • Recently many researchers have focused on management of Historical trajectories of moving objects in Euclidean spaces due to numerous sizes of accumulated data over time. However, the movement of moving objects in real applications generally has some constraints, for example vehicles on roads can only travel along connected road networks. In this paper, we propose an indexing method for trajectories of moving objects on road networks in order to process the network-based spatiotemporal range query. Our method contains the connect information of road networks to use the network distance for query processing, deals with trajectories which are represented by road segments in road networks, and manages them using multiple R-trees assigned per each road segment. Furthermore, it has a structure to be able to share R-tree among several road segments in large road networks. Consequently, we show that our method takes about 30% less in node accesses for the network-based spatiotemporal range query processing than other methods based on the Euclidean distance by experiments.

Improvement of RT-PCR Sensitivity for Fruit Tree Viruses by Small-scale dsRNA Extraction and Sodium Sulfite

  • Lee, Sin-Ho;Kim, Hyun-Ran;Kim, Jae-Hyun;Kim, Jeong-Soo
    • The Plant Pathology Journal
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    • v.20 no.2
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    • pp.142-146
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    • 2004
  • Woody plant tissues contain great amounts of phenolic compounds and polysaccharides. These substances inhibit the activation of reverse transcriptase and/or Taq polymerase in RT-PCR. The commonly used multiple-step protocols using several additives to diminish polyphenolic compounds during nucleic acid extraction are time consuming and laborious. In this study, sodium sulfite was evaluated as an additive for nucleic acid extraction from woody plants and the efficiency of RT-PCR assay of commercial nucleic acid extraction kits and small-scale dsRNA extraction was compared. Sodium sulfite was used as an inhibitor against polyphenolic oxidases and its effects were compared in RNA extraction by commercial extraction kit and small-scale double-stranded RNA (dsRNA) extraction method for RT-PCR. During nucleic acid extraction, addition of 0.5%-1.5%(w/v) of sodium sulfite to lysis buffer or STE buffer resulted in lighter browning by oxidation than extracts without sodium sulfite and improved the RT-PCR detection. When commercial RNA extraction kit was used, optimal concentrations of sodium sulfite were variable according to the tested plant. However, with dsRNA as RT-PCR template, sodium sulfite 1.5% in STE buffer improved the detection efficiency of Apple chlorotic leaf spot virus (ACLSV) and Apple stem grooving virus (ASGV) in fruit trees, and reduced the unspecific amplifications signi-ficantly. Furthermore, when viruses existed at low titers in host plant, small-scale dsRNA extractions were very reliable.

Wisteria Vein Mosaic Virus Detected for the First Time in Iran from an Unknown Host by Analysis of Aphid Vectors

  • Valouzi, Hajar;Hashemi, Seyedeh-Shahrzad;Wylie, Stephen J.;Ahadiyat, Ali;Golnaraghi, Alireza
    • The Plant Pathology Journal
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    • v.36 no.1
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    • pp.87-97
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    • 2020
  • The development of reverse transcription-polymerase chain reaction using degenerate primers against conserved regions of most potyviral genomes enabled sampling of the potyvirome. However, these assays usually involve sampling potential host plants, but identifying infected plants when they are asymptomatic is challenging, and many plants, especially wild ones, contain inhibitors to DNA amplification. We used an alternative approach which utilized aphid vectors and indicator plants to identify potyviruses capable of infecting common bean (Phaseolus vulgaris). Aphids were collected from a range of asymptomatic leguminous weeds and trees in Iran, and transferred to bean seedlings under controlled conditions. Bean plants were tested serologically for potyvirus infections four-weeks postinoculation. The serological assay and symptomatology together indicated the presence of one potyvirus, and symptomology alone implied the presence of an unidentified virus. The partial genome of the potyvirus, encompassing the complete coat protein gene, was amplified using generic potyvirus primers. Sequence analysis of the amplicon confirmed the presence of an isolate of Wisteria vein mosaic virus (WVMV), a virus species not previously identified from Western Asia. Phylogenetic analyses of available WVMV sequences categorized them into five groups: East Asian-1 to 3, North American and World. The Iranian isolate clustered with those in the World group. Multiple sequence alignment indicated the presence of some genogroup-specific amino acid substitutions among the isolates studied. Chinese isolates were sister groups of other isolates and showed higher nucleotide distances as compared with the others, suggesting a possible Eastern-Asian origin of WVMV, the main region where Wisteria might have originated.

High-speed W Address Lookup using Balanced Multi-way Trees (균형 다중 트리를 이용한 고속 IP 어드레스 검색 기법)

  • Kim, Won-Iung;Lee, Bo-Mi;Lim, Hye-Sook
    • Journal of KIISE:Information Networking
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    • v.32 no.3
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    • pp.427-432
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    • 2005
  • Packet arrival rates in internet routers have been dramatically increased due to the advance of link technologies, and hence wire-speed packet processing in Internet routers becomes more challenging. As IP address lookup is one of the most essential functions for packet processing, algorithm and architectures for efficient IP address lookup have been widely studied. In this paper, we Propose an efficient I address lookup architecture which shows yeW good Performance in search speed while requires a single small-size memory The proposed architecture is based on multi-way tree structure which performs comparisons of multiple prefixes by one memory access. Performance evaluation results show that the proposed architecture requires a 280kByte SRAM to store about 40000 prefix samples and an address lookup is achieved by 5.9 memory accesses in average.

Realistic and Efficient Radio Propagation Model for V2X Communications

  • Khokhar, Rashid Hafeez;Zia, Tanveer;Ghafoor, Kayhan Zrar;Lloret, Jaime;Shiraz, Muhammad
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.8
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    • pp.1933-1954
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    • 2013
  • Multiple wireless devices are being widely deployed in Intelligent Transportation System (ITS) services on the road to establish end-to-end connection between vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) networks. Vehicular ad hoc networks (VANETs) play an important role in supporting V2V and V2I communications (also called V2X communications) in a variety of urban environments with distinct topological characteristics. In fact, obstacles such as big buildings, moving vehicles, trees, advertisement boards, traffic lights, etc. may block the radio signals in V2X communications. Their impact has been neglected in VANET research. In this paper, we present a realistic and efficient radio propagation model to handle different sizes of static and moving obstacles for V2X communications. In the proposed model, buildings and large moving vehicles are modeled as static and moving obstacles, and taken into account their impact on the packet reception rate, Line-of-sight (LOS) obstruction, and received signal power. We use unsymmetrical city map which has many dead-end roads and open faces. Each dead-end road and open faces are joined to the nearest edge making a polygon to model realistic obstacles. The simulation results of proposed model demonstrates better performance compared to some existing models, that shows proposed model can reflect more realistic simulation environments.

Classification of Feature Points Required for Multi-Frame Based Building Recognition (멀티 프레임 기반 건물 인식에 필요한 특징점 분류)

  • Park, Si-young;An, Ha-eun;Lee, Gyu-cheol;Yoo, Ji-sang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.3
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    • pp.317-327
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    • 2016
  • The extraction of significant feature points from a video is directly associated with the suggested method's function. In particular, the occlusion regions in trees or people, or feature points extracted from the background and not from objects such as the sky or mountains are insignificant and can become the cause of undermined matching or recognition function. This paper classifies the feature points required for building recognition by using multi-frames in order to improve the recognition function(algorithm). First, through SIFT(scale invariant feature transform), the primary feature points are extracted and the mismatching feature points are removed. To categorize the feature points in occlusion regions, RANSAC(random sample consensus) is applied. Since the classified feature points were acquired through the matching method, for one feature point there are multiple descriptors and therefore a process that compiles all of them is also suggested. Experiments have verified that the suggested method is competent in its algorithm.