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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

iPCM Telemetry System

Leite, Nelson Paiva Oliveira, Carvalho, Marco Aurélio 10 1900 (has links)
ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / The execution of experimental Flight Test Campaign (FTC) provides all information required for the aircraft development, operation and certification. Typically the execution of a FTC encompasses three major systems as follows: Flight Test Instrumentation System (FTI) that is basically a measurement system; Real-Time Telemetry Link (RTL); and Ground Telemetry System (GTS). At the early days, for the development of small aircrafts (i.e. Fighter), the primary source for FTI data was provided by the RTL due to inherent limitations of the open reel airborne data recorders (i.e. media and size), operating under high-dynamics condition. Nowadays with the introduction of solid-state data recording devices, data integrity and reliability is no longer an issue. At the ITC 2010 Blue Ribbon Panel, Mr. Thomas Beard, the executive Director of the Air Force Flight Test Center in Edwards Air Force Base emphasized the need to reduce refly and to improve FTC efficiency. Such statement imposes a new paradigm in Telemetry, which is to improve RTL integrity and reliability level equivalent to the solid-state data recording devices. Therefore the Telemetry community will be able to execute test point validation for refly reduction and quasi realtime data reduction analysis for efficiency improvement. The major solutions that address such issue are Spatial Diversity (SD) architectures and the iNet. The SD solution requires multiple antenna system (which is very expensive) that could still produce ineffective results at high-dynamics test points (e.g. Spin). At the beginning the iNet consortium proposed the usage of TCP protocol for data transmission. Problems associated with TCP limitations such as data latency and overhead lead to the usage of UDP protocol that does not guarantee the packet delivery. To properly address these issues the IPEV R&D group proposes the iPCM Telemetry architecture to be used as RTL. The iPCM uses hybrid architecture for data transmission taking the advantage of legacy digital transmitters combined with iNet-based transceivers to retrieve missing data. The development and the evaluation of iPCM architecture will be executed as a PhD Thesis in ITA University. The expected performance and benefits of iPCM are presented and discussed.
82

Telemetry Network Systems (TMNS) RF Link Management Quality of Service

O'Connell, Ray, Webster, Lyle, Kaba, James 10 1900 (has links)
ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / In the Telemetry Network System (TmNS) the prioritization of mission traffic is performed by internal radio queuing disciplines and the Link Manager performing adjustments to each radio transmit window in the TDMA network. These processes combine to provide the QoS traffic handling across the range. The radios provide the transmit packet prioritization using queuing disciplines which can be assigned to mission traffic flows. The Link Manager on the ground receives periodic reports of queue levels from each radio and performs transmit capacity adjustments based on internal radio and network wide conditions. Presented in this paper is the design of this TmNS RF Link Management QoS process with OPNET modeling and simulation results.
83

Link Adaptation for Energy Constrained Networks

Alemdar, Ali 02 December 2008 (has links)
Relay terminals are often used in tandem in sensor networks to lessen nodal communication burden. In this light we investigate the problem of power allocation amongst nodes in a relay network in order to maximize the overall achievable rate using link adaptive transmission protocols. We focus on the physical layer characteristics and implementation issues of link adaptation in order to develop a bit-level simulator needed to accurately model the rate performance of such a system. Optimal power allocation values, power adaptation policies, and switching levels for several link adaptive policies over a broad class of Rician fading channels are calculated. Furthermore, the maximum achievable rate for two and three link relay networks using our bit-level simulator and optimal power allocation values for collocated channel distributions is simulated. An overall achievable rate comparison between several link adaptive protocols is also investigated. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2008-11-26 14:52:27.65
84

A model for managing information flow on the World Wide Web

Evans, Michael Paul January 2001 (has links)
This thesis considers the nature of information management on the World Wide Web. The web has evolved into a global information system that is completely unregulated, permitting anyone to publish whatever information they wish. However, this information is almost entirely unmanaged, which, together with the enormous number of users who access it, places enormous strain on the web's architecture. This has led to the exposure of inherent flaws, which reduce its effectiveness as an information system. The thesis presents a thorough analysis of the state of this architecture, and identifies three flaws that could render the web unusable: link rot; a shrinking namespace; and the inevitable increase of noise in the system. A critical examination of existing solutions to these flaws is provided, together with a discussion on why the solutions have not been deployed or adopted. The thesis determines that they have failed to take into account the nature of the information flow between information provider and consumer, or the open philosophy of the web. The overall aim of the research has therefore been to design a new solution to these flaws in the web, based on a greater understanding of the nature of the information that flows upon it. The realization of this objective has included the development of a new model for managing information flow on the web, which is used to develop a solution to the flaws. The solution comprises three new additions to the web's architecture: a temporal referencing scheme; an Oracle Server Network for more effective web browsing; and a Resource Locator Service, which provides automatic transparent resource migration. The thesis describes their design and operation, and presents the concept of the Request Router, which provides a new way of integrating such distributed systems into the web's existing architecture without breaking it. The design of the Resource Locator Service, including the development of new protocols for resource migration, is covered in great detail, and a prototype system that has been developed to prove the effectiveness of the design is presented. The design is further validated by comprehensive performance measurements of the prototype, which show that it will scale to manage a web whose size is orders of magnitude greater than it is today.
85

Projective links and their invariants /

Mroczkowski, Maciej, January 2004 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 2 uppsatser.
86

Link invariants, quantized superalgebras and the Kontsevich integral /

Geer, Nathan, January 2004 (has links)
Thesis (Ph. D.)--University of Oregon, 2004. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 123-125). Also available for download via the World Wide Web; free to University of Oregon users.
87

A readership investigation of Link, the internal employee magazine of Oscar Mayer & Company

Johnson, Frank Irvin, January 1975 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1975. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
88

Modulation Coding In A Radio Link And Data Transfer Application Using L2 VPN Ethernet Over MPLS In A Large Network

Varli, Dogan January 2015 (has links)
In this thesis work, the locations where we are unable to reach via fiber are considered for wireless transmission links. In the practical part of this thesis different modulation techniques and antenna sizes were analyzed  in order to provide the most efficient way of data transmission. The data between this wireless links was transfered using MPLS L2 VPN solution.   According to improving technology and increasing internet usage, the communication speed, which is between users and providers, becomes more inevitable for transmitting data without any delays. More than one users might use same connection line for transmitting their packets and it is able to be caused an online traffic and some delays and data loss could occur. In this circumstance, high rate internet demands would lead extra costs for Internet Service Providers (ISPs) and users.   In the introduction part, a brief description for the history of communications and basic equipments for Radio Link and Fiber Optic cable are done.   In the theory part, detailed information was provided about modulation techniques and multiplexing techniques followed by general information about computer networks  and comprehensive information about OSI layers.   In the process and result parts, program outputs for Path Loss design which was used for R/L was mentioned in a detailed way. After that, Ethernet Over MPLS L2 VPN was highlighted and a simulation from point-to-point "Ethernet Over MPLS L2 VPN” was conducted in GNS3 software. Furthermore, the simulation for point-to-multipoint case was then applied  in a laboratory environment in order to achieve the desired result.   In the result part, different R/L simulation results are compared to determine the optimized modulation technique and antenna sizes which could then be merged with simulation results from the previous part.
89

Shear Forces Developed in Link Beams of Eccentric Braced Frames

Evans, John Paul 01 May 2012 (has links)
Eccentric braced frames have been a topic of research in seismic design over the past twenty years. The idea of eccentric bracing is a relatively new method used in practice to satisfy seismic design requirements. They have been proven to give reliable results in tests using simulated earthquake events, as well as provide an economical advantage over other framing methods. Two one-story eccentric braced frame models were created using computer generated finite element analysis. The example chosen for this study are discussed further. The maximum shear stress distribution in the link beam of the frame, using finite element analysis, will be investigated herein. The results of the shear stress produced gives insight to shear forces developed in the link beam of eccentric braced frames. The results of shear forces produced are compared with those calculated by structural engineers using commonly used hand calculated equations.
90

Hipertextualidade na construção do sentido das notícias na web: um estudo do portal de notícias JC Online

Luna, Diógenes D' Arce Cardoso de 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T16:32:26Z (GMT). No. of bitstreams: 2 arquivo90_1.pdf: 2674211 bytes, checksum: 07d001920c34ec7bcff304b6c6d0a697 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Desde o seu surgimento, na década de 1990, a web configurou-se como cenário em mudanças: palco de experimentos que, no tocante à mídia, ganham força no período de convergência que reconfigura as mídias tradicionais. Na web, vista como ambiente de convergência, as narrativas em hipermídia estruturam-se por uma lógica diversa das narrativas tradicionais. Interatividade, personalização, hipertextualidade e multimidialidade são algumas das reconfigurações em voga. No tocante às experiências com o jornalismo, incluído no sistema midiático que a web põe em processo, um elemento lingüístico toma lugar como responsável pela construção do sentido nas narrativas jornalísticas em hipermídia: o link. Links e lexias são as unidades paradigmáticas fundamentais para a elaboração dessas narrativas. Essa dissertação propõe uma análise sobre o papel do link na construção de narrativas jornalísticas em hipermídia, especialmente em portais de notícia. Para estudo de caso, o portal do grupo Jornal do Commercio de Comunicação foi escolhido, o JC Online. A evolução do jornalismo na web, os elementos discursivos dos hipertextos de portais e as unidades paradigmáticas do sistema hipertextual serão estudadas, sob a luz de teorias e metodologias como a análise de discurso, semiótica discursiva e análise descritiva do portal em estudo. Intenta-se, com este trabalho, fornecer subsídios para o entendimento dessas narrativas noticiosas hipermidiáticas na web, buscando no cerne na linguagem o apoio para tal intenção

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