• Title/Summary/Keyword: DPIM

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Packet Error Rate comparsion of Different Modulation Formats over Terrestrial Optical Wireless Communication in Turbulent Atmosphere (교란대기 지상 광무선 통신에서 변조방식에 따른 패킷 오류율 비교)

  • Hong, Kwon-Eui
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39B no.12
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    • pp.856-863
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    • 2014
  • In the terrestrial optical wireless communication(OWC), the performance is affected by atmospheric turbulence and particles in the air. The received signal power loss mainly is caused by turbulence and scattering. To minimize the adverse atmospheric effects, the OWC used optical signal modulation, such as OOK, PPM and DPIM. In this paper, the packet error rate(PER) was analyzed above three modulation methods to ground optical link in atmospheric turbulence, scattering and link distance. The OWC system used three wavelengths which are 850nm, 1310nm and 1550nm. I assumed the atmospheric turbulence intensity is weak, so the refractive index is $Cn2{\approx}10-14m-2/3$ and the visibility is 2km. The numerical results shown that the L-DPIM scheme and the wavelength 1550nm are better than other modulation methods and wavelengths.

A QoS of Delay supporting Scheme for IP Multicast Routing (인터넷 멀티캐스트 라우팅에서 지연시간에 대한 QoS를 지원하는 방법)

  • Park, Se-Hun;Ahn, Sang-Hyun
    • Journal of KIISE:Information Networking
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    • v.28 no.4
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    • pp.498-507
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    • 2001
  • For the Internet multicast routing, there are some protocols researched. This paper presents a new protocol called DPIM (Delay-bounded PIM) to support QoS of delay in multicast routing. This protocol is based on PIM-SM. When the specified delay bound is not satisfied by dynamic membership, the RP (Rendezvous Point) of shared tree is changed and the shared tree is reconstructed. Therefore, the QoS of delay is always supported in this protocol. Through performance analysis and comparison with other protocol, we certify that this protocol is pertinent.

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A Product Information Model based on Design Process for Enterprise Integration (기업통합을 위한 설계프로세스 기반의 제품정보모델)

  • 김종수
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.52
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    • pp.229-239
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    • 1999
  • Enterprise integration, which aims to enhance an enterprise's competitive edge, requires a highly structured product information model as a common product database. Previous research works on this issue have been narrowly focused on the transformation of product information between various operation areas, leading to a situation where enterprise integration lacks a formal method of information modeling. In this paper, research works and issues surrounding product information modeling for enterprise integration are reviewed, and the requirements for a product information model are identified. A product information model called L3DPIM (Layered Three Dimentional Product Information Model) is proposed, which is based on a feature-based design process. This model is expected to serve as a modeling paradigm for enterprise integration.

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Extraction of Spatial Information of Facility Using Terrestrial and Aerial Photogrammetric Analysis (지상사진과 항공사진 해석에 의한 시설물 공간정보 추출)

  • Sohn, Duk-Jae;Lee, Seung-Hwan
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.1 s.24
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    • pp.51-59
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    • 2003
  • This study intended to extract the spatial data and attribute data from the images of terrestrial and aerial photographs and to compile the digital map from the images using various kinds of photogrammetric analysis. The Three Dimensional Frame Model (3DFM) was produced from multiple images of terrestial photographs, and the Three Dimensional Photo Image Model (3DPIM) was made using 3DFM and image patches of terrestrial photo, which is useful for identifying the feature and characteristics of the object. In addition, the spatial data base for the buildings, roads and supplementary facilities in the objective area was updated by the vectorizing procedures with small scale areal photos.

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