• Title/Summary/Keyword: Split and merge

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A Multiple Access Scheme Using Split and Merge Algorithm for Centralized Wireless MAC Protocols (중앙 집중형 무선 매체 접근 제어 프로토콜을 위한 분할 및 합병 알고리즘을 이용한 다중 접근 방안)

  • Kim Min-Su;Byun Tae-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.8B
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    • pp.757-763
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    • 2006
  • In this paper, a novel multiple access scheme using SMA(Split and Merge Algorithm) is proposed to reduce the accessdelay of wireless MAC protocols. The key idea of the SMA is to dynamically split and merge the contending terminals depending on their traffic loads for effective control of access to the channels. The SMA divides the collided terminals into several sub-groups if a collision occurs and merges the idle terminals of the split sub-groups into their original group. The merge algorithm can be used to resolve collision and split operation can be used to dynamic group management. The simulation results indicate that our algorithm may provide a higher throughput and a lower collision rate than the existing algorithms, especially under heavy traffic loads.

A Parallel Algorithm for Image Segmentation on Mesh-connected MIMD System

  • Jeon, Byeong-Moon;Jeong, Chang-Sung
    • Journal of Korea Society of Industrial Information Systems
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    • v.3 no.1
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    • pp.258-268
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    • 1998
  • This paper presents two sequential advanced split and merge algorithms and a parallel image segmentation algorithm based on them. First, the two advanced methods are obtained from the combination of edge detection and classic split and merge to solve the inherent problems of the classical method. Besides, the parallel image segmentation algorithm on mesh-connected MIMD system considers three types in the merge stage to reduce the communication overhead between processors, such as intraprocessor merge, interprocessor with boundary merge, and interprocessor without boundary merge. Finally , we prove that the proposed algorithms achieve the improved performance by implementing them.

Hybrid Modeling and Control for Platoon Maneuvers in Automated Highway Systems (군집주행 기동을 위한 하이브리드 모델링 및 제어기 설계)

  • 전성민;최재원
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.12
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    • pp.1014-1022
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    • 2002
  • An objective of Automated Highway Systems (AHS) is to increase the safety and throughput of the existing highway infrastructure by introducing traffic automation. AHS is an example of a large scale, multiagent complex dynamical system and is ideally suited for a hierarchical hybrid controller. We discuss a design issue of efficient hybrid controllers for the platoon maneuvers on AHS. For the modeling of a hybrid system including the merge and split operations, a safety distance policy is introduced for the merge and split operations. After that, the platoon system will be modeled by a hybrid system In addition, a hybrid controller for the proposed merge and split operation models is presented. Finally, the performance of the proposed hybrid control scheme is demonstrated via scenarios for platoon maneuvers.

Text Region Extraction of Natural Scene Images using Gray-level Information and Split/Merge Method (명도 정보와 분할/합병 방법을 이용한 자연 영상에서의 텍스트 영역 추출)

  • Kim Ji-Soo;Kim Soo-Hyung;Choi Yeong-Woo
    • Journal of KIISE:Software and Applications
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    • v.32 no.6
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    • pp.502-511
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    • 2005
  • In this paper, we propose a hybrid analysis method(HAM) based on gray-intensity information from natural scene images. The HAM is composed of GIA(Gray-intensity Information Analysis) and SMA(Split/Merge Analysis). Our experimental results show that the proposed approach is superior to conventional methods both in simple and complex images.

Hybrid Control for the Platoon Maneuvers with Lane Change

  • Jeon, Seong-Min;Park, Jae-Weon
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.160.4-160
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    • 2001
  • Many physical systems today are modeled by interacting continuous and discrete states that influence the dynamic behavior. Hybrid system models, suitable for describing the essential dynamics of a fairly large class of physical systems in control engineering applications, contain both continuous dynamics and discrete dynamics. We discuss the design of efficient hybrid controllers for the platoon maneuvers on an AHS. For the modeling of a hybrid system including the merge and split operations, we introduce the safety distance policy for the merge and split operations. Then, the platoon system will be modeled by a hybrid system. In addition, the hybrid controller for the proposed merge and split operation models will be presented. Finally, we will demonstrate our scenarios ...

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Energy Efficient Clustering Scheme in Sensor Networks using Splitting Algorithm of Tree-based Indexing Structures (트리기반 색인구조의 분할 방법을 이용한 센서네트워크의 에너지 효율적인 클러스터 생성 방법)

  • Kim, Hyun-Duk;Yu, Bo-Seon;Choi, Won-Ik
    • Journal of Korea Multimedia Society
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    • v.13 no.10
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    • pp.1534-1546
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    • 2010
  • In sensor network systems, various hierarchical clustering schemes have been proposed in order to efficiently maintain the energy consumption of sensor nodes. Most of these schemes, however, are hardly applicable in practice since these schemes might produce unbalanced clusters or randomly distributed clusters without taking into account of the distribution of sensor nodes. To overcome the limitations of such hierarchical clustering schemes, we propose a novel scheme called CSM(Clustering using Split & Merge algorithm), which exploits node split and merge algorithm of tree-based indexing structures to efficiently construct clusters. Our extensive performance studies show that the CSM constructs highly balanced clustering in a energy efficient way and achieves higher performance up to 1.6 times than the previous clustering schemes, under various operational conditions.

Vehicle Detection based on the Haar-like feature and Image Segmentation (영상분할 및 Haar-like 특징 기반 자동차 검출)

  • Choi, Mi-Soon;Lee, Jeong-Hwan;Suk, Jung-Hee;Roh, Tae-Moon;Shim, Jae-Chang
    • Journal of Korea Multimedia Society
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    • v.13 no.9
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    • pp.1314-1321
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    • 2010
  • In this paper, we study about the vehicle detection algorithm which is in the process of travelling from the road. An input image is segmented by means of split and merge algorithm. And two largest segmented regions are removed for reducing search region and speed up processing time. In order to detect the back side of the front vehicle considers a vertical/horizontal component, uses an integral image with to apply Haar-like methods which are the possibility of shortening a calculation time, classified with SVM. The simulation result of the method which is proposed appeared highly.

Indexing Methods of Splitting XML Documents (XML 문서의 분할 인덱스 기법)

  • Kim, Jong-Myung;Jin, Min
    • Journal of Korea Multimedia Society
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    • v.6 no.3
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    • pp.397-408
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    • 2003
  • Existing indexing mechanisms of XML data using numbering scheme have a drawback of rebuilding the entire index structure when insertion, deletion, and update occurs on the data. We propose a new indexing mechanism based on split blocks to cope with this problem. The XML data are split into blocks, where there exists at most a relationship between two blocks, and numbering scheme is applied to each block. This mechanism reduces the overhead of rebuilding index structures when insertion, deletion, and update occurs on the data. We also propose two algorithms, Parent-Child Block Merge Algorithm and Ancestor-Descendent Algorithm which retrieve the relationship between two entities in the XML hierarchy using this indexing mechanism. We also propose a mechanism in which the identifier of a block has the information of its Parents' block to expedite retrieval process of the ancestor-descendent relationship and also propose two algorithms. Parent-Child Block Merge Algorithm and Ancestor-Descendent Algorithm using this indexing mechanism.

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A method for multiple identical object tracking (동일한 다중 물체 추적 기법)

  • Chun, Gi-Hong;Kang, Hang-Bong
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.679-680
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    • 2006
  • 이 논문에서는 가장 많이 알려진 tracking 알고리즘인 Particle-Filter 의 단점을 motion vector 를 기반으로 예측한 sampling 방법과 K-means clustering 을 이용하여 해결하려고 한다. Tracking 에서의 문제는 다중의 유사한 객체들이 merge 후 split 될 때 제대로 추적을 하지 못하고 한 객체만을 추적 한다는 데에 있었다. 그리고 split 되어 객체별로 추적이 가능하더라도 이전에 추적한 객체를 올바로 labeling 하지 못하는 문제가 있다는 것이다. 이 merge-split 문제는 개량된 K-means clustering 을 이용하고, labeling 문제는 motion vector 를 이용한 개량된 sampling 방법으로 개선하였다.

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Efficient All-to-All Personalized Communication Algorithms in Wormhole-Routed Networks (웜홀 방식의 네트워크에서 효율적인 다대다 개별적 통신 알고리즘)

  • 김시관;강오한;정종인
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.7_8
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    • pp.359-369
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    • 2003
  • We present efficient generalized algorithms for all-to-all personalized communication operations in a 2D torus. All-to-all personalized communication, or complete exchange, is at the heart of numerous applications, such as matrix transposition, Fast Fourier Transform(FFT), and distributed table lookup. Some algorithms have been Presented when the number of nodes is power-of-2 or multiple-of-four form, but there has been no result for general cases yet. We first present complete exchange algorithm called multiple-Hop-2D when the number of nodes is in the form of multiple-of-two. Then by extending this algorithm, we present two algorithms for an arbitrary number of nodes. Split-and-Merge algorithm first splits the whole network into zones. After each zone performs complete exchange, merge is applied to finish the desired complete exchange. By handling extra steps in Double-Hop-2D algorithm, Modified Double-Hop-2D algorithm performs complete exchange operation for general cases. Finally, we compare the required start-up time for these algorithms.