• Title/Summary/Keyword: Path extension

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Cross-Layer Service Discovery Scheme for Hybrid Ad-hoc Networks (하이브리드 애드-혹 네트워크를 위한 크로스-레이어 서비스 검색 기법)

  • Kim, Moon-Jeong;Eom, Young-Ik
    • The KIPS Transactions:PartC
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    • v.16C no.2
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    • pp.223-228
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    • 2009
  • Efficient service discovery mechanism is a crucial feature for a hybrid ad-hoc network supporting extension of a wireless ad-hoc network to the Internet. We propose an efficient cross-layer service discovery mechanism using non-disjoint multi-path source routing protocol for hybrid ad-hoc networks. Our scheme has advantages of multi-path routing protocol and cross-layer service discovery. Intuitively, it is not difficult to imagine that the cross-layer service discovery mechanism could result in a decreased number of messages compared to the traditional approach for handling routing independently from service discovery. By simulation, we show that faster route recovery is possible by maintaining multiple routing paths in each node, and the route maintenance overhead can be reduced by limiting the number of multiple routing paths and by maintaining link/node non-disjoint multi-path.

An adaptive Control of the Nonholonomic Mobile AGV

  • Han, Zhe-Yong;Huh, Uk-Youl
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.307-310
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    • 2001
  • Mobile AGV is one of the nonholon-omic systems. The integration of the kinematic adaptive controller for the dynamic in this pa-per introduction a motion control problem's dynamic state feedback as well as output feedback tracking laws will be constructed with the adaptive extension of the controller is proposed. Feedback control strategies for mobile AGV are important to compensate for disturabances and errors in the initial condition. The problems of path following or tracking and of stabilization about a constant configuration have been treated as separate problems for nonholonomic mobile AGV.

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GENERALIZED REIDEMEISTER NUMBER ON A TRANSFORMATION GROUP

  • Park, Ki Sung
    • Korean Journal of Mathematics
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    • v.5 no.1
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    • pp.49-54
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    • 1997
  • In this paper we study the generalized Reidemeister number $R({\varphi},{\psi})$ for a self-map $({\varphi},{\psi}):(X,G){\rightarrow}(X,G)$ of a transformation group (X, G), as an extension of the Reidemeister number $R(f)$ for a self-map $f:X{\rightarrow}X$ of a topological space X.

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Low-Complexity Symbol Timing Offset Estimation Schemes for OFDM Systems

  • Park, So-Ra;Jung, Young-Ho;Lee, Son-In
    • ETRI Journal
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    • v.24 no.3
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    • pp.247-250
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    • 2002
  • In this paper, we propose three symbol syn-chronization schemes for Orthogonal Frequency Division Multiplex (OFDM) systems. The cyclic extension preceding OFDM symbols is of decisive importance for these schemes. The first scheme uses the phase-differential coding of the received OFDM signal. The second and the third schemes use the length of the received OFDM signal. All three schemes make symbol synchronization possible, even though there is a frequency off-set in the system. Simulation results show that these schemes can be used to synchronize an OFDM system over AWGN and multi-path fading channels.

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Migration Using Reordering Recovery in Wired/Wireless Networks

  • Lee, Dong-Chun
    • Convergence Security Journal
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    • v.7 no.4
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    • pp.115-121
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    • 2007
  • Due on failures of communication nodes for the wireless and wired networks, mobile agents may be blocked even if there is available service in the networks. To solve it, we propose migration policy with reordering of the paths to guarantee the migration of mobile agents and the paper will provide the extension with the autonomous migration of mobile agents.

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INEQUALITIES FOR THE ARGUMENTS LYING ON LINEAR AND CURVED PATH

  • Nagaraja, K.M.;Araci, Serkan;Lokesha, V.;Sampathkumar, R.;Vimala, T.
    • Honam Mathematical Journal
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    • v.42 no.4
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    • pp.747-755
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    • 2020
  • The mathematical proof for establishing some new inequalities involving arithmetic, geometric, harmonic means for the arguments lying on the paths of triangular wave function (linear) and new parabolic function (curved) over the interval (0, 1) are discussed. The results representing an extension as well as strengthening of Ky Fan Type inequalities.

Storage and Retrieval of XML Documents Without Redundant Path Information (경로정보의 중복을 제거한 XML 문서의 저장 및 질의처리 기법)

  • Lee Hiye-Ja;Jeong Byeong-Soo;Kim Dae-Ho;Lee Young-Koo
    • The KIPS Transactions:PartD
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    • v.12D no.5 s.101
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    • pp.663-672
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    • 2005
  • This Paper Proposes an approach that removes the redundancy of Path information and uses an inverted index, as an efficient way to store a large volume of XML documents and to retrieve wanted information from there. An XML document is decomposed into nodes based on its tree structure, and stored in relational tables according to the node type, with path information from the root to each node. The existing methods using path information store data for all element paths, which cause retrieval performance to be decreased with increased data volume. Our approach stores only data for leaf element path excluding internal element paths. As the inverted index is made by the leaf element path only, the number of posting lists by key words become smaller than those of the existing methods. For the storage and retrieval of U data, our approach doesn't require the XML schema information of XML documents and any extension of relational database. We demonstrate the better performance of on approach than the existing approaches within the scope of our experiment.

The Design of the Ultra-Wideband Slot Antenna by Using a Semi-Circular Extension (반원 확장을 이용한 초광대역 슬롯 안테나 설계)

  • Lee Jung-Nam;Lee Hyo-Kyoung;Jang Hwa-Yeol;Park Jong-Kweon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.9 s.100
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    • pp.941-948
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    • 2005
  • In this paper, we have proposed a Ultra-Wideband slot notch antenna by using a semi-circular extension. The proposed antenna cover the entire UWB band(3.1${\~}$10.6 GHz) and notch out the IEEE 802.1la frequency band(5.15${\~}$5.825 GHz) by inserting a $\lambda$/4 length slot into the patch. A prototype antenna was fabricated on FR-4( ${\epsilon}_r$ =4.4, substrate thickness=0.8 mm) and measured for VSWR characteristics. The measured notched frequency variations versus frequency for different slot length. The path loss and group delay were measured. The proposed antenna also show a good gain flatness(1.9 dBi) except the IEEE 802.1la frequency band.

A Study of Routing and Signaling Extensions of GMPLS for QoS Provision in NGN (NGN에서 QoS 제공을 위한 GMPLS의 라우팅 및 시그널링 화장 연구)

  • 장석기;박광채
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.5
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    • pp.925-933
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    • 2003
  • Network is expected to be developed into optical Internet network collected IP layer and optical layer, but GMPLS is risen at the transitional evolution stage because of the present technology level. GMPLS that MPLS is extended and generalized is able to support not only the packet switching device but also the devices which perform switching in time, wavelength, and space domain. To implement the common control plane to these various switching types, GMPLS extends the existing MPLS signaling and routing protocol. In this paper, we describe the overview of GMPLS technology, and then we will refer to the OSPF(Open Shortest Path First), which was used to exchange the status information of link, as the plan of routing extension to exchange the information of various link type, bandwidth, link protection type etc. And also, we describe the definition of new protocol, so called, LMP that is a signaling protocol for solving complex problem which manages hundreds and thousands of links between two nodes. And we will examine and analyze the plan of signaling protocol extension to apply signaling protocol RSVP-TE(Resource Reservation Protocol) for traffic engineering in MPLS to network, and the message objects and formats associated with modified RSVP.

A Comparative Study on Communication of Agricultural Innovation (농업 기술 전파 커뮤니케이션에 관한 비교 연구)

  • Kim, Sung-Soo
    • Journal of Agricultural Extension & Community Development
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    • v.7 no.1
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    • pp.121-136
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    • 2000
  • This study reports on a comparison between the Korean diffusion of agricultural innovation or extension service and the cooperative extension service in the United States of America. It focuses on relevant differences between the two systems and provides recommendation for improvement of the Korean system to insure success in important areas related to the diffusion of agricultural innovations. After a comparative study on diffusion of innovations it is clear that: in order to have a productive agriculture that makes effective and efficient use of natural resources and helps achieve sustainability goals, a mechanism that delivers knowledge to agricultural communities must be established and maintained. This mechanism is clearly an agricultural extension service that is cooperatively funded by federal, state and local governments and that insures participation of constituents in the process of establishing priorities and evaluating achievements. The success of US agriculture, the most productive in the world, is to a large degree to the Cooperative Extension Service. Based on the results of this study and the differences of the United States and Korea, the following recommendations should be emphasized for more effective communication for agricultural innovation and rural development in Korea: 1) In order to insure that extension educators are high caliber professional individuals, it is important to establish a system that nationally recognizes these individuals as such, and that provides a professional development path. 2) The results of the decision of transfer of extension educators to local governments has not yielded positive outcomes, especially in terms of professional status. It is clearly demonstrable that valuable professionals are leaving the service, that local governments do not have the will and resources to implement a successful extension program. 3) Because of the critical importance of diffusing innovations to agricultural producers in order to insure and quality and steady food supply, it is of critical importance that these issues be addressed before the extension service is further deteriorated. Given the cement situation, it is clear that the extension service should become nationally supported again in cooperation with local and state governments and that extension professionals be given appropriate rank at the national level, commesurate with their peers in research and teaching. 4) The common current committee practice of lengthy reporting and short discussion needs to be changed to one that results in char, brief and substantive action oriented goals. Joint participation by researchers, extension educators and farmers should be encouraged in planning, implementation and evaluation of communication for agricultural innovations. Roles and functions of committees for institutional cooperation, and or agricultural extension committees should be enlarged. 5) Extension educators should be encouraged to adopt new communication technologies to improve their diffusion of innovations methods. Agricultural institutions and organizations should be encouraged to adopt farmer-first and or client-oriented approach in agricultural extension and diffusion of agricultural technologies. The number, complexity and rapid change of information in agricultural extension require the development of a computer based information and report system to support agricultural extension. 6) To facilitate and expand the further development of communication for agricultural innovation and rural development, agricultural communication programs in universities especially in colleges of agriculture and life sciences. 7) To strengthening the sense of national and social responsibility communication for agricultural innovation and rural development among students in agricultural colleges and universities through participation in learning activities by proactive recruitment. 8) To establish and reinforce a policy that insures participation in communication for agricultural innovation and regal development activities. 9) To improve further development of communication for agricultural innovation and rural development in Korea, more research activities should be encouraged.

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