• Title/Summary/Keyword: Hierarchical Networks

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Hierarchical Image Segmentation by Binary Split for Region-Based Image Coding (영역기반 영상부호화를 위한 이진 분열에 의한 계층적인 영상분할)

  • Park, Young-Sik;Song, Kun-Woen;Han, Kyu-Phil;Lee, Ho-Young;Nam, Jae-Yeal;Ha, Yeong-Ho
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.8
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    • pp.68-76
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    • 1998
  • In this paper, a new morphological image segmentation algorithm of hierarchical structure by binary split is proposed. It splits a region with the lowest quality into two regions using only two markers having the highest contrast. Therefore, it improves the quality of image with limited regions and reduces contour information which is not sensitive to human visual system, when compared with the conventional algorithm. It is appropriate to PSTN, LAN, and mobile networks, of which the available transmission bandwidth is very limited, because the number of regions can be controlled. And the proposed algorithm shows very simple structure because it doesn't need post processing to eliminate small regions and reduces much computation by using only structuring element of small size at simplification step of each hierarchical structure when compared with the conventional algorithm.

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Network Mobility Support Using Router-based Binding Update Scheme in Hierarchical Mobile IP (Hierarchical Mobile IP에서 라우터기반 바인딩 업데이트 방법을 이용한 네트워크 이동성 지원)

  • Kim, Ju-Hyun;Lee, Kyung-Geun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.7B
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    • pp.668-676
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    • 2009
  • Hierarchical Mobile 1Pv6(HM1Pv6) have been proposed by IETF(Internet Engineering Task Force) beginning from Mobile 1Pv6 for mobility support in IP networks, however these researches relying on client based mobility support have not been drawn attention due to excessive consumption of wireless resources and long handover delay. In this paper, we propose the Router-based Binding Update(RBU) scheme to solve problems in existing client-based mobility support schemes. The router registers location information of mobile nodes through Neighbor Discovery protocol without additional codes for the RBU scheme to a terminal operated by existing HMlPv6. By using this the RBU scheme is designed so that it can support partial nupport based mobility and reduce handover latency rather than using HMIPv6. It is analysed and compared with existing HMIPv6 to verify efficiency of the RBU scheme. As a result, the RBU scheme has outperformed existing HMIPv6 by 15% in terms of macro handover delay especially when long delay on wireless links exists.

Embedding Algorithms of Hierarchical Folded HyperStar Network (계층적 폴디드 하이퍼스타 네트워크의 임베딩 알고리즘)

  • Kim, Jong-Seok;Lee, Hyeong-Ok;Kim, Sung-Won
    • The KIPS Transactions:PartA
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    • v.16A no.4
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    • pp.299-306
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    • 2009
  • Hierarchical Folded HyperStar Network has lower network cost than HCN(n,n) and HFN(n,n) which are hierarchical networks with the same number of nodes. In this paper, we analyze embedding between Hierarchical Folded HyperStar HFH($C_n,C_n$) and Hypercube, HCN(n,n), HFN(n,n). The results of embedding are that HCN(n,n), HFN(n,n) and Hypercube $Q_{2n}$ can be embedded into HFH($C_n,C_n$) with expansion $\frac{C^n}{2^{2n}}$ and dilation 2, 3, and 4, respectively. Also, HFH($C_n,C_n$) can be embedded into HFN(2n,2n) with dilation 1. These results mean so many developed algorithms in Hypercube, HCN(n,n), HFN(n,n) can be used efficiently in HFH($C_n,C_n$).

An Energy-Efficient Data Aggregation using Hierarchical Filtering in Sensor Network (센서 네트워크에서 계층적 필터링을 이용한 에너지 효율적인 데이터 집계연산)

  • Kim, Jin-Su;Park, Chan-Heum;Kim, Chong-Gun;Kang, Byung-Wook
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.1 s.45
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    • pp.73-82
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    • 2007
  • This paper proposes how to reduce the amount of data transmitted in each sensor and cluster head in order to lengthen the lifetime of sensor network by data aggregation of the continuous queries. The most important factor of refuting the sensor's energy dissipation is to reduce the amount of messages transmitted. The method proposed is basically to combine clustering, in-network data aggregation and hierarchical filtering. Hierarchical filtering is to divide sensor network by two tiers when filtering it. First tier performs filtering when transmitting the data from cluster member to cluster head, and second tier performs filtering when transmitting the data from cluster head to base station. This method is much more efficient and effective than the previous work. We show through various experiments that our scheme reduces the network traffic significantly and increases the network's lifetime than existing methods.

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Packet Processing Analysis of OSPF Routing Protocol (OSPF라우팅 프로토콜의 패킷 처리 분석)

  • 최승한;주성순
    • Proceedings of the IEEK Conference
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    • 2000.11a
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    • pp.477-480
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    • 2000
  • Open Shortest Path First(OSPF) is a dynamic, hierarchical routing protocol designed to support routing in TCP/IP networks. Currently, OSPF is used as Interior Gateway Protocol(IGP) in many routers. In this paper, we analyze the variation of number of OSPF routing packets in case of changing the network configuration. The results show that the number of packets in case of adding new link increase five times than one in case of normal operation.

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Performance Analysis of Qos over CBQ Estimator (CBQ Estimator을 고려한 QoS 성능 분석)

  • 박우출;박상준;이병호
    • Proceedings of the IEEK Conference
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    • 2000.11a
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    • pp.287-290
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    • 2000
  • This paper analyze link-sharing mechanisms in packet networks based on the hierarchical class based queueing. The CBQ outlines a set of flexible, efficiently implemented gateway mechanisms that can meet a range of service and link-sharing requirements. We have analyzed the Class level(B, C, D) using the EWMA (Exponential Weighted Moving Average) weight value and EWMA average limit value.

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TCP Performance Evaluation of Multicast-based Mobility Support Scheme in IPv6 Networks (IPv6 네트워크에서 멀티캐스트 기반 이동성 제공 방안의 TCP 성능 분석)

  • 박호현;우미애
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.757-759
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    • 2004
  • 무선 통신 기술이 급속히 발전하면서 이동 중 데이터 통신이 가능하도록 하기 위한 연구가 활발하게 이루어지고 있다. 본 논문에서는 효율적인 이동성 제공 방안으로 멀티캐스트 기반 이동성 제공 방안을 제안하고 모의실험을 통하여 TCP 트래픽에 대한 성능을 분석하였다. 본 논문에서 제안한 방안은 이동 단말이 외부 도메인 내에서 핸드오프 시 자신의 위치 갱신을 멀티캐스트 그룹에 조인하는 방법으로 바인딩 갱신에 따른 추가적인 신호를 지역 내에서 처리함으로써 Mobile IPv6와 Hierarchical Mobile IPv6 보다 TCP 처리율을 높임을 알 수 있었다.

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Input Noise Immunity of Multilayer Perceptrons

  • Lee, Young-Jik;Oh, Sang-Hoon
    • ETRI Journal
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    • v.16 no.1
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    • pp.35-43
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    • 1994
  • In this paper, the robustness of the artificial neural networks to noise is demonstrated with a multilayer perceptron, and the reason of robustness is due to the statistical orthogonality among hidden nodes and its hierarchical information extraction capability. Also, the misclassification probability of a well-trained multilayer perceptron is derived without any linear approximations when the inputs are contaminated with random noises. The misclassification probability for a noisy pattern is shown to be a function of the input pattern, noise variances, the weight matrices, and the nonlinear transformations. The result is verified with a handwritten digit recognition problem, which shows better result than that using linear approximations.

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