• Title/Summary/Keyword: B+ tree

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Korean Character Recognition with Tree Structure Using Representative Images (대표영상을 이용한 나무구조의 한글문자 인식)

  • 김정우;정수길;조웅호;김성용;김수중
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.4
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    • pp.18-29
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    • 1994
  • For the efficient recognition of Korean Alphabets, we proposed the tree structure algorithm which was based on K-tuple NRF-SDF using representative images as training images. Representative images consisted of ECP-SDF images of several consonants or vowels. To reduce the effect of sidelobe in the output correlation plane, we used the representative images as training images and obtained the elements of a vector inner product matrix using the peak value of AMPOF correlation of training images with one another. The proposed algorithm consisted of three main-step containing several substeps. In filter synthesis of each step, representative images were used as training images in the first and the second main-step and each consonant or vowel was used as training images in the third main-step. The performance of this algorithm is demonstrated by computer simulation and optical experiment.

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A Study for Performance Improvement of RDBMS on Using Bitmap Index (Bitmap Index를 이용한RDBMS 성능향상 기법에 관한 연구)

  • Jeon, Sang-Hwa;Lee, Eun-Bae
    • Proceedings of the Korea Information Processing Society Conference
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    • 2005.05a
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    • pp.11-14
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    • 2005
  • 데이터베이스 성능이 저하되면, 가장 먼저 SQL 튜닝을 고려한다. SQL 튜닝에서 가장 주의 깊게 사용 해야하는 부분이 바로 Index의 설정과 관련된 부분이다. 본 논문에서 OLAP 환경에서 다양하고 복잡한 질의처리 요구와 관련하여, B-Tree Index의 문제점을 개선하고 질의 성능을 향상시키기 위해서 Bitmap Index를 사용하였다. 또한, Bitmap Index 사용의 최적 임계점을 추적하기 위하여, 데이터 분포도와 조건절의 복잡도를 조사하였으며, 샘플링된 질의문을 기준으로 B-Tree Index를 사용하였을 때와 Bitmap Index를 사용하였을 때의 비교 실험을 통하여 Bitmap Index의 사용으로 RDBMS의 성능향상이 있음을 증명하였다.

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Phytochemistry and Pharmacology of Moringa oleifera Lam

  • Paikra, Birendra Kumar;Dhongade, Hemant kumar J.;Gidwani, Bina
    • Journal of Pharmacopuncture
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    • v.20 no.3
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    • pp.194-200
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    • 2017
  • Moringa oleifera Lam. or munga is one of the most important plant widely cultivated in India. It belongs to family Moringaceae. This plant is widely used as nutritional herb and contains valuable pharmacological action like anti-asthmatic, anti-diabetic, hepatoprotective, anti-inflammatory, anti-fertility, anti-cancer, anti-microbial, anti-oxidant, cardiovascular, anti-ulcer, CNS activity, anti-allergic, wound healing, analgesic, and antipyretic activity, Moringa oleifera Lam. The plant is also known as Horse - radish tree, Drumstick tree. Every part of this plant contains a valuable medicinal feature. It contain rich source of the vitamin A, vitamin C and milk protein. Different types of active phytoconstituents like alkaloids, protein, quinine, saponins, flavonoids, tannin, steroids, glycosides, fixed oil and fats are present. This plant is also found in the tropical regions. Some other constituents are niazinin A, niazinin B and niazimicin A, niaziminin B. The present review discusses the phytochemical composition, medicinal uses & pharmacological activity of this plant.

A Shortest Path Allocation Algorithm for the Load Balancing in Hypercubes (하이퍼큐브 상에서의 부하 분산을 우한 최단 경로 할당 알고리듬)

  • 이철원;임인칠
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.4
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    • pp.27-36
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    • 1993
  • This paper proposes a shortest path allocation algorithm over the processors on the hypercube system based on the message passing techniques with the optimized module allocation. On multiprocessor systems, how to divide one task into multiple tasks efficiently is an important issue due to the hardness of the life cycle estimation of each process. To solve the life cycle discrepancies, the appropriate task assignment to each processor and the flexible communications among the processors are indispensible. With the concurrent program execution on hypercube systems, each process communicaties to others with the method of message passing. And, each processor has its own memory. The proposed algorithm generates a callable tree out of the module, assigns the weight factors, constructs the allocation graph, finds the shortest path allocation tree, and maps them with hypercube.

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An Auxiliary Log Area for In-Page Logging Scheme (In-Page 로깅 기법을 위한 보조 로그 영역)

  • Van, Jae-Kwang;Jin, Rize;Kim, Sungsoo;Chung, Tae-Sun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2014.04a
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    • pp.729-731
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    • 2014
  • 플래시 메모리에서 B-tree 데이터를 저장하고 관리[4, 5]할 때 빈번한 수정과 구조변동으로 인해 발생하는 블록에 대한 쓰기와 지우기 연산의 비용으로 인해 플래시 메모리의 사용 수명을 단축시키는 문제를 해결하기 위해 현재 많이 쓰이고 있는 로그 저장방식을 검토하고 이를 효율적으로 B-tree에 저장하고 관리하도록 동적 블록 그룹핑과 순환 순서 기반의 저장 알고리즘으로 제안 된 GRR (Ground Round Robin) 기법을 보조 로그 블록을 할당하여 머지횟수를 줄일 수 있는 알고리즘을 제안한다.

Asynchronous plural I/O index scan using flash SSD (플래시 SSD를 활용한 비동기 복수 I/O 인덱스 스캔)

  • Park, Ji-Young;Kang, Woon-Hak;Lee, Sang-Won
    • Proceedings of the Korea Information Processing Society Conference
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    • 2012.11a
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    • pp.1389-1391
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    • 2012
  • 인덱스는 데이터 검색을 빠르게 하기 위하여 사용되며, 많은 데이터를 저장하는 대용량 데이터베이스 시스템은 B+-tree 인덱스를 주로 사용한다. B-tree 인덱스를 사용하여 범위 검색을 수행하는 경우 레코드 각각에 대하여 I/O를 요청함으로써 프로세스가 자주 대기(waiting) 상태가 되어 많은 오버헤드가 발생하였다. 이러한 문제를 해결하고자 본 논문에서 비동기 복수 I/O 인덱스 스캔방법을 제안한다. 비동기 복수 I/O 인덱스 스캔이 최고 6.5배 빠른 성능을 보였다.

Evaluation of the Diversity of Cyclodextrin-Producing Paenibacillus graminis Strains Isolated from Roots and Rhizospheres of Different Plants by Molecular Methods

  • Vollu Renata Estebanez;Fogel Rafael;Santos Silvia Cristina Cunha dos;Mota Fabio Faria da;Seldin Lucy
    • Journal of Microbiology
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    • v.44 no.6
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    • pp.591-599
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    • 2006
  • To address the diversity of cyclodextrin-producing P. graminis strains isolated from wheat roots and rhizospheres of maize and sorghum sown in Australia, Brazil, and France, restriction fragment length polymorphism analysis of part of genes encoding RNA polymerase (rpoB-RFLP) and DNA gyrase subunit B (gyrB-RFLP) was used to produce genetic fingerprints. A phylogenetic tree based on rpoB gene sequences was also constructed. The isolates originated from Brazil could be separated from those from Australia and France, when data from the rpoB-based phylogenetic tree or gyrB-RFLP were considered. These analyses also allowed the separation of all P. graminis strains studied here into four clusters; one group formed by the strains GJK201 and $RSA19^T$, second group formed by the strains MC22.02 and MC04.21, third group formed by the strains TOD61, TOD 221, TOD302, and TOD111, and forth group formed by all strains isolated from plants sown in Cerrado soil, Brazil. As this last group was formed by strains isolated from sorghum and maize sown in the same soil (Cerrado) in Brazil, our results suggest that the diversity of these P. graminis strains is more affected by the soil type than the plant from where they have been isolated.

Synoptic Change Characteristics of the East Asia Climate Appeared in Seoul Rainfall and Climatic Index Data (서울지점 강우자료와 기후지표자료에 나타난 동아시아 기후의 종관적 변화특성)

  • Hwang, Seok Hwan;Kim, Joong Hoon;Yoo, Chulsang;Chung, Gunhui
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.409-417
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    • 2009
  • In this study it was assessed the accuracy of the Chukwooki rainfall data in Seoul by comparing with tree-ring width index data, sunspot numbers, southern oscillation index (SOI) and global temperature anomaly. And it was investigated the correlations of climatic change and change characteristics in past north-east asia by comparisons of tree-ring width index data in near Korea. The results of this study shows that Chukwooki rainfall data has the strong reliance since the trends and depths of change are very well matched with other comparative data. And with the results by compared with tree-ring width index data in six sites of near Korea, climates of north-east asia are changed with strong correlations as being temporal and spatial and longterm periodic possibility of reproducing are exist on those changes. However characteristics of climate change post 1960 A.D. are investigated as represented differently to past although statistical moving characteristics or changing criterion are within the limitations of reproducing phase in the past since they represent the different trends and irregularity and their frequencies are increase. The results of this study are widely used on long-term forecasting for climate change in north-east asia.

Within0tree Disribution of matsucoccus thunbergianae on Pinus thunbergiana (해송에서의 솔껍질깍지의 벌레 수상분포 양식)

  • 박승찬
    • Korean journal of applied entomology
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    • v.33 no.2
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    • pp.114-121
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    • 1994
  • Population densities of intermediate nymphs and egg saw of Matsucoccus thunbergianae, a major insect pest of Pinus thunbergiona in southern coastal area of Korean peninsula, were est~mated. Tree samples of ca. 10cm D.B.H. were collected from old infestation area and newly invaded area. The numben of plimaly branches per tree were not significantly different by the locality, but those of secondaly and smaller branches were smaller in old infestation area The numbers of intermediate nymphs per tree in old infestation area and in newly invaded area were 10.8 and 13.1 times more than those on the trunk, respectively Approximately between 4, 200 and 208, 500 nymphs per tree were estimated. Men secondaw and smaller bmnch samples collected from the basal part of middle crown height, or from the central or the basal part of lower crown height, the number of samples required for the emr range of 20% were 21 and 11 far 10-20cm and 20-3 crn long branches, respectively. Approx~mately 63.6% of egg sacs of the whole tree were on the trunk. The node/intemode bearing the largest branch had the highest egg sac density; including that, four adjacent nodes/intemodes had ca. 37% of egg saw on the trunk.

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A Study on The Improvement of Douglas-Peucker's Polyline Simplification Algorithm (Douglas-Peucker 단순화 알고리듬 개선에 관한 연구)

  • 황철수
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.17 no.2
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    • pp.117-128
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    • 1999
  • A Simple tree-structured line simplification method, which exactly follows the Douglas-Peucker algorithm, has a strength for its simplification index to be involved into the hierarchical data structures. However, the hierarchy of simplification index, which is the core in a simple tree method, may not be always guaranteed. It is validated that the local property of line features in such global approaches as Douglas-Peucker algorithm is apt to be neglected and the construction of hierarchy with no thought of locality may entangle the hierarchy. This study designed a new approach, CALS(Convex hull Applied Line Simplification), a) to search critical points of line feature with convex hull search technique, b) to construct the hierarchical data structure based on these critical points, c) to simplify the line feature using multiple trees. CALS improved the spatial accuracy as compared with a simple tree method. Especially CALS was excellent in case of line features having the great extent of sinuosity.

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