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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.
1

APPLICATION OF EMERGING COMMUNICATION TECHNOLOGIES TO THE CREATION OF A "VIRTUAL RANGE"

Kight, William D., Pfister, Robert E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper addresses the creation of a large virtual-range environment whereby multiple, geographically dispersed, test ranges may operate in concert to support test operations. The most significant benefit of the virtual range environment is the time-sharing of costly processing resources. Other benefits include improved reliability and responsiveness of inter-range data transfer. This paper will focus on existing and near-term technology that may be applied to create a virtual-range and will address the technological and economic advantages and disadvantages of TDM vs. ATM approaches.
2

Two-way Time Transfer Using Synchronous Optical Network (SONET) Optical Fiber Technology

Kuo, I-Yu 04 July 2000 (has links)
We transport the standard time signal by using the single-mode fiber (SMF) media through the synchronous optical network (SONET)/ synchronous digital hierarchy (SDH) data signal, in which the time signal generated from the atomic clock was inserted into the unused bytes in the overhead of the SONET/SDH OC-3 155 Mb/s frame. Based on the NIST MODEM architecture, which was developed by the National Institute of Standard and Technology in the States, the time transfer system is composed of the control unit of the OC-3 transceiver module and the time-signal transmiting/receiving unit. We design and fabricate the required time-signal transmitting/receiving circuits and the control and monitoring circuits. The personal computer (PC) can read/write and monitor the operation status of the optical transceiver module through the control circuit, and the 1-PPS (pulse per second) time signal can therefore be read/written from/into the transceiver module. The frequency stability of about 2.6E-16 within one day can be achieved for this 1310-nm optical-fiber-based time transfer system over a 35-km SMF link without using electronic regererator. Such stability performance is comparable with that of today¡¦s GPS-based time transfer system.
3

Shallow Water Training Range

Reid, Robert 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During the cold war, undersea warfare (USW) was perceived as a large-area, deep-water operation. The need for USW has recently shifted to the shallow water, littoral environment. Consequently, US naval forces must train to operate in these littoral environments where regional conflicts are most likely to occur. In light of these requirements the Shallow Water Training Range (SWTR) has been initiated. Telemetry is used in the following areas of SWTR: fiber optic, microwave, RF and underwater. Only phase 1 of 8 phases of the program is executing therefore SWTR is a good opportunity for telemetry industry involvement.
4

ASYNCHRONOUS TRANSFER MODE (ATM) CONVERSION DEVICE (ACD)

Harris, Carol, Mascari, Michele, Rice, Kevin, Smith, Jeff, Steedman, John 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Asynchronous Transfer Mode (ATM) Conversion Device (ACD) System is based on state-of-the-art ATM technology. The system interfaces between high-rate ECL/RS-422 raw data bitstreams and Synchronous Optical Network (SONET) OC-3 fiber. The SONET OC-3 interface uses ATM Adaptation Layer Type Five (AAL5) format. The system exceeds its 50 Mbps raw data, single stream requirement and provides single stream raw data throughput at rates up to 75 Mbps. With ATM and SONET packaging overhead, this translates into 90 Mbps on the OC-3 fiber. In addition to high-rate throughput, the system provides multiplexing and demultiplexing of multiple stream throughput based on the ATM cell header Virtual Path and Virtual Channel Identifier (VPI/VCI) values. The system is designed with the flexibility to provide between three and six throughput channels. All of which are multiplexed/demultiplexed to and from the same OC-3 interface. Multiple stream cumulative raw data throughput rates of up to 80 Mbps, or 96 Mbps on the fiber, have successfully run.
5

An evaluation of management techniques for SONET/SDH Telecommunication networks

Lim, Wee Shoong 09 1900 (has links)
Approved for public release; distribution is unlimited / A study of SONET network management applications and the load they impart to the network is conducted to provide a better understanding of the capability of various management approaches. In this study, a SONET network is set up in the Advanced Networking Laboratory of the Naval Postgraduate School using four Cisco ONS 15454s. Next, two Element Management Systems, the Cisco Transport Controller and the Cisco Transport Manager, are deployed onto the SONET network. Subsequently, the network traffic of the Element Management Systems is captured and analyzed using a packet analyzer. Link utilization of the two tools is computed using the first-order statistics of the captured traffic distributions. In addition, the Hurst parameter is estimated using the variance-index plot technique (which uses higher-orders statistics of the modeled distributions) to determine the captured traffic's degree of self-similarity. Finally, the calculated utilization is extrapolated to obtain the link utilization for 2500 network elements (the maximum number supported by the Cisco Transport Manager). The result obtained is useful in determining the maximum number of network elements (Cisco ONS 15454s) that the Cisco Transport Manager can support from a network loading point of view. / Civilian, Ministry of Defense, Singapore
6

A performance analysis of management information due to data traffic provisioning in a SONET/SDH communications network

Tay, Yeong Kiang Winston. 06 1900 (has links)
An evaluation of the performance of a SONET management system was conducted to better understand its management capabilities due to network disruptions in the presence of a traffic load. This study analyzed the Cisco Transport Manager (CTM) which manages a testbed of four Cisco ONS15454 optical systems. The network was injected with HTTP and FTP traffic generated by the Spirent Smartbits system installed with TeraMetrics Gigabit Ethernet modules and load calibration configured by the Spirent Avalanche software. To simulate real-world situations, power disruptions were applied to the network while collecting CTM traffic using Ethereal. Using queuing analysis, the arrival rates and service times were computed for various CTM traffic components and a utilization for 2500 network elements (NE) extrapolated. Self-similarity analysis was performed and the logvariance was plotted to extract the Hurst values. Finally, the results and findings were compared with prior research for loading and no-loading cases. The results of this study are useful in determining the maximum number of network elements manageable in a disruptive environment. Final analysis on the effects of link utilization on the queue size showed that the CTM is able to manage more NEs when the network is disrupted. Unfortunately, managing more NEs increases the queue size even though the utilization was found to be 0.83 for 5450 NEs. Consequently, in order to maintain a moderate queue size, the maximum number of NEs manageable was found to be 2495. This value is close to CISCO's specification of a CTM server managing a maximum of 2500 NEs.
7

Groupage de trafic à coût minimum dans les réseaux anneaux WDM

Jarray, Abdallah January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
8

Routing and bandwidth management for multiparty videoconferencing. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Feng Gang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 169-181). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
9

Refroidissement d'atomes par laser de la diffusion spatiale dans un réseau quasi-périodique aux instabilités du piège magnéto-optique /

Di Stefano, Andrea. Verkerk, Philippe. Hennequin, Daniel January 2001 (has links) (PDF)
Thèse de doctorat : Lasers, molécules et rayonnement atmosphérique : Lille 1 : 2001. / Résumé en français et en anglais. Bibliogr. p. 203-216.
10

Optimisation des communications multicast sous contraintes

Molnár, Miklós January 2008 (has links)
Habilitation à diriger des recherches : Informatique : Rennes 1 : 2008. / Bibliogr. p. 137-163.

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