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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.
21

Návrh vybrané části standardu IEEE 802.1Q / Design of selected IEEE 802.1Q standard parts

Kliment, Filip January 2018 (has links)
This thesis deals with network substandards from the TSN group (IEEE 802.1Q), which deal with prioritization of network traffic in TSN networks. These sub-standards include 802.1QBV and 802.1QBU, which have been described in more detail and compared in terms of network permeability and latency. Substandard 802.1QBU was chosen for the design implementation in FPGA. The design was described in VHDL. The designed design was verified by simulations, using self-tests. The work includes synthesis and time analysis.
22

Návrh vybrané části standardu IEEE 802.1Q / Design of selected IEEE 802.1Q standard parts

Kliment, Filip January 2018 (has links)
This thesis deals with network substandards from the TSN group (IEEE 802.1Q), which deal with prioritization of network traffic in TSN networks. These sub-standards include 802.1QBV and 802.1QBU, which have been described in more detail and compared in terms of network permeability and latency. Substandard 802.1QBU was chosen for the design implementation in FPGA. The design was described in VHDL. The devloped design was verified by simulations, using self-tests. The work includes synthesis and time analysis.
23

A bi-level system dynamics modeling framework to evaluate costs and benefits of implementing Controller Pilot Data Link Communications and Decision Support Tools in a non-integrated and integrated scenario

Sen, Debayan 04 May 2004 (has links)
A modeling framework to evaluate the costs and benefits of implementation of Controller Pilot Data Link Communication (CPDLC), and Air Traffic Management (ATM) decision support tools is proposed in this paper. The benefit/cost evaluation is carried out for four key alternatives namely alternative A: Do nothing scenario (only voice channel), alternative B: Voice channel supplemented with CPDLC, alternative C: Alternative B with ATM tools in a non-integrated scenario and finally alternative D: Alternative B with ATM tools in an integrated scenario. It is a bi-level model that captures the linkages between various technologies at a lower microscopic level using a daily microscopic model (DATSIM) and transfers the measures of effectives to a higher macroscopic level. DATSIM stands for Data Link and Air Traffic Technologies SIMulation and it simulates air traffic in the enroute sector and terminal airspace for a single day and captures the measures of effectiveness at a microscopic level and feeds its output to the macroscopic annual model which then runs over the entire life cycle of the system. Airspace dwell time benefit data from the microscopic model is regressed into three dimensional benefit surfaces as a function of the equipage level of aircraft and aircraft density and embedded into the macroscopic model. The main function of the annual model is to ascertain economic viability of any deployment schedule or alternative over the entire life cycle of the system. The life cycle cost model is composed of four modules namely: Operational benefits module, Safety benefit module,Technology cost module and Training cost module. Analysis using the model showed that an enroute sector gets congested at aircraft densities greater 630 per day. This is mainly because the controller workload gets saturated at that traffic volume per day. Benefits realized in alternatives B, C and D as compared to alternative A increased exponentially at traffic densities greater than 630 i.e. when controller workload for alternative A becomes saturated. / Master of Science
24

A Computer Model to Estimate Benefits of Data Link Mandates and Reduced Separations across North Atlantic Organized Track System

Gunnam, Aswin Kumar 04 January 2013 (has links)
The International Civil Aviation Organization (ICAO) proposed to introduce new operational strategies across the North Atlantic (NAT) airspace. This includes Minimum Navigation Performance Specifications (MNPS) airspace to increase the capacity and efficiency of the North Atlantic Organized Track System (NAT OTS). A numerical integration and simulation model called North Atlantic Simulation and Modeling (NATSAM) is developed to study the effects of these new strategies on NAT system performance. The model is capable of investigating the effects of implementing different operational policies and strategies proposed by ICAO such as Reduced Lateral Separation Minimum (RLatSM), NAT Region Data link mandate (DLM), Reduced Longitudinal Separation Minimum (RLongSM), cruise-climb profiles, variable Mach number profiles, step-climbs and other operational concepts to be studied by the ICAO. NATSAM models the individual flight performance using the Base of Aircraft Data (BADA) 3.9 model to calculate the flight profiles and fuel burn. The model employs simple heuristics to execute flight track assignment in the organized track system for each scenario. Detailed outputs and also aggregated outputs are provided by the model from which various key performance indicators (KPI) can be derived to assess the performance of the system. / Master of Science
25

GPS TEST RANGE MISSION PLANNING

Roberts, Iris P., Hancock, Thomas P. 11 1900 (has links)
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / TASC is currently developing for the GPS Range Applications Joint Program Office (RAJPO) the mission planner which will be used by test ranges procuring RAJPOdeveloped GPS test range instrumentation. Test Range User Mission Planner (TRUMP) is a user-friendly, PC-resident tool which aids in deploying and utilizing GPS-based test range assets. In addition to providing satellite/jammer visibility (for a Digital Terrain Elevation Data (DTED) range map) and dilution-of-precision (DOP) information, TRUMP features: C Time history plots of time-space-position information (TSPI) C Performance based on a dynamic GPS/inertial system simulation C Time history plots of TSPI data link connectivity C DTED maps with user-defined cultural features C Two-dimensional coverage plots of ground-based test range assets. This paper will discuss TRUMP’s role on the test ranges and its current features. In addition, the functionality to be added during the next development phase will be presented.
26

Short range reconnaissance unmanned aerial vehicle / S.J. Kersop.

Kersop, Stefanus Jacobus January 2009 (has links)
Unmanned aerial vehicles (UAVs) have been used increasingly over the past few years. Special Forces of various countries utilise these systems successfully in war zones such as Afghanistan. The biggest advantage is rapid information gathering without endangering human lives. The South African National Defence Force (SANDF) also identified the need for local short range aerial reconnaissance and information gathering. A detailed literature survey identified various international players involved in the development of small hand-launch UAV systems. Unfortunately, these overseas systems are too expensive for the SANDF. A new system had to be developed locally to comply with the unique requirements, and budget, of the SANDF. The survey of existing systems provided valuable input to the detailed user requirement statement (URS) for the new South African development. The next step was to build a prototype using off-the-shelf components. Although this aircraft flew and produced good video images, it turned out to be unreliable. The prototype UAV was then replaced with a standard type model aircraft, purchased from Micropilot. Some modifications were needed to ensure better compliance with the URS. Laboratory and field tests proved that the aircraft can be applied for aerial images, within range of 10 km from the ground control station (GCS). The major limitation is that it can only fly for 40 minutes. Furthermore, the airframe is not robust, needing repairs after only 15 flights. Although the system has shortcomings, it has already been used successfully. It is expected that improved battery technologies and sturdier light-weight materials will further help to improve the system beyond user specifications. / Thesis (MIng (Electrical Engineering))--North-West University, Potchefstroom Campus, 2010.
27

Short range reconnaissance unmanned aerial vehicle / S.J. Kersop.

Kersop, Stefanus Jacobus January 2009 (has links)
Unmanned aerial vehicles (UAVs) have been used increasingly over the past few years. Special Forces of various countries utilise these systems successfully in war zones such as Afghanistan. The biggest advantage is rapid information gathering without endangering human lives. The South African National Defence Force (SANDF) also identified the need for local short range aerial reconnaissance and information gathering. A detailed literature survey identified various international players involved in the development of small hand-launch UAV systems. Unfortunately, these overseas systems are too expensive for the SANDF. A new system had to be developed locally to comply with the unique requirements, and budget, of the SANDF. The survey of existing systems provided valuable input to the detailed user requirement statement (URS) for the new South African development. The next step was to build a prototype using off-the-shelf components. Although this aircraft flew and produced good video images, it turned out to be unreliable. The prototype UAV was then replaced with a standard type model aircraft, purchased from Micropilot. Some modifications were needed to ensure better compliance with the URS. Laboratory and field tests proved that the aircraft can be applied for aerial images, within range of 10 km from the ground control station (GCS). The major limitation is that it can only fly for 40 minutes. Furthermore, the airframe is not robust, needing repairs after only 15 flights. Although the system has shortcomings, it has already been used successfully. It is expected that improved battery technologies and sturdier light-weight materials will further help to improve the system beyond user specifications. / Thesis (MIng (Electrical Engineering))--North-West University, Potchefstroom Campus, 2010.
28

Modelování protokolů IS-IS a TRILL / Modelling IS-IS and TRILL

Marek, Marcel January 2013 (has links)
In this thesis, we describe the principles of IS-IS routing protocol. We introduce the current state of implementation of this protocol within the simulation framework OMNeT++. We present the implementation of the IS-IS protocol created within the ANSA project. Moreover, we employ its variant called TRILL that is nowadays deployed as replacement of STP in data-center environment. The aim is to enable the modelling of the protocols without the need having to build physical architecture.
29

SPACE COMMUNICATION DEMONSTRATION USING INTERNET TECHNOLOGY

Israel, Dave, Parise, Ron, Hogie, Keith, Criscuolo, Ed 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper presents work being done at NASA/GSFC by the Operating Missions as Nodes on the Internet (OMNI) project to demonstrate the application of Internet communication technologies to space communication. The goal is to provide global addressability and standard network protocols and applications for future space missions. It describes the communication architecture and operations concepts that will be deployed and tested on a Space Shuttle flight in July 2002. This is a NASA Hitchhiker mission called Communication and Navigation Demonstration On Shuttle (CANDOS). The mission will be using a small programmable transceiver mounted in the Shuttle bay that can communicate through NASA’s ground tracking stations as well as NASA’s space relay satellite system. The transceiver includes a processor running the Linux operating system and a standard synchronous serial interface that supports the High-level Data Link Control (HDLC) framing protocol. One of the main goals will be to test the operation of the Mobile IP protocol (RFC 2002) for automatic routing of data as the Shuttle passes from one contact to another. Other protocols to be utilized onboard CANDOS include secure login (SSH), UDP-based reliable file transfer (MDP), and blind commanding using UDP. The paper describes how each of these standard protocols available in the Linux operating system can be used to support communication with a space vehicle. It will discuss how each protocol is suited to support the range of special communication needs of space missions.
30

INTERNET TECHNOLOGY FOR FUTURE SPACE MISSIONS

Rash, James, Hogie, Keith, Casasanta, Ralph 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Ongoing work at National Aeronautics and Space Administration Goddard Space Flight Center (NASA/GSFC), seeks to apply standard Internet applications and protocols to meet the technology challenge of future satellite missions. Internet protocols and technologies are under study as a future means to provide seamless dynamic communication among heterogeneous instruments, spacecraft, ground stations, constellations of spacecraft, and science investigators. The primary objective is to design and demonstrate in the laboratory the automated end-to-end transport of files in a simulated dynamic space environment using off-the-shelf, low-cost, commodity-level standard applications and protocols. The demonstrated functions and capabilities will become increasingly significant in the years to come as both earth and space science missions fly more sensors and the present labor-intensive, mission-specific techniques for processing and routing data become prohibitively. This paper describes how an IP-based communication architecture can support all existing operations concepts and how it will enable some new and complex communication and science concepts. The authors identify specific end-to-end data flows from the instruments to the control centers and scientists, and then describe how each data flow can be supported using standard Internet protocols and applications. The scenarios include normal data downlink and command uplink as well as recovery scenarios for both onboard and ground failures. The scenarios are based on an Earth orbiting spacecraft with downlink data rates from 300 Kbps to 4 Mbps. Included examples are based on designs currently being investigated for potential use by the Global Precipitation Measurement (GPM) mission.

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