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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.
171

Co-operative conflict resolution in autonomous aircraft operations using a multi-agent approach

Ruiz, Miguel Angel Vilaplana January 2002 (has links)
No description available.
172

Individual channel analysis and design and its application to helicopter flight control

Dudgeon, Graham John William January 1996 (has links)
No description available.
173

Dual Function Transponder: A Data Link for the Next Generation

DeViso, Hans, Troth, Bill 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / Future U.S. Navy at-sea and littoral battle group training range instrumentation requires a new, secure, high data rate link This link must be capable of providing the ranges with the capacity to increase the number of players, increase the amount of threat simulation, and allow an improved Global Positioning System (GPS) based position tracking system to be implemented This paper describes a Dual Function Transponder (DFT) capable of operating on any R-CUBED (Relay, Reporter, Responder) based range as well as any TACTS/ACMI range without modification of either range type. In addition, the DFT provides a new increased data rate capability for use by planned future ranges, enabling a dramatic increase in the number of participants as well as significantly increasing the quantity of data that can be communicated by each player. Miniaturization and programmability are the keys to this development and many of the methods used are described.
174

The Common Airborne Instrumentation System Program Management Overview

Brown, Thomas R., Jr. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The Department of Defense, through a Tri-Service Program Office, is developing the Common Airborne Instrumentation System (CAIS) to promote standardization, commonality, and interoperability among aircraft test instrumentation systems. The advent of CAIS will change how the DoD test community conducts business. The CAIS program will allow aircraft test and evaluation facilities to utilize common airborne systems, ground support equipment, and technical knowledge for airborne instrumentation systems. The CAIS Program Office will conduct requirements analyses, manage system upgrades, and provide full life cycle support for this system. It is initiating several requirements contracts to provide direct ordering opportunities for DoD users to easily procure defined test instrumentation hardware. The program office will provide configuration management, inventory control, maintenance support, system integration, engineering support, and software management. In addition, it will continue to enhance the current system and develop new items to meet future requirements. Where existing equipment provides added benefit, this equipment may be added to the official CAIS family.
175

Instrumentation and Telemetry Systems for Free-Flight Drop Model Testing

Hyde, Charles R., Massie, Jeffrey J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents instrumentation and telemetry system techniques used in free-flight research drop model testing at the NASA Langley Research Center. The free-flight drop model test technique is used to conduct flight dynamics research of high performance aircraft using dynamically scaled models. The free-flight drop model flight testing supplements research using computer analysis and wind tunnel testing. The drop models are scaled to approximately 20% of the size of the actual aircraft. This paper presents an introduction to the Free-Flight Drop Model Program which will be followed by a description of the current instrumentation and telemetry systems used at the NASA Langley Research Center, Plum Tree Test Site. The paper describes three telemetry downlinks used to acquire the data, video, and radar tracking information from the model. Also described are two telemetry uplinks, one used to fly the model employing a ground based flight control computer and a second to activate commands for visual tracking and parachute recovery of the model. The paper concludes with a discussion of free-flight drop model instrumentation and telemetry system development currently in progress for future drop model projects at the NASA Langley Research Center.
176

ON-SKY PERFORMANCE ANALYSIS OF THE VECTOR APODIZING PHASE PLATE CORONAGRAPH ON MagAO/Clio2

Otten, Gilles P. P. L., Snik, Frans, Kenworthy, Matthew A., Keller, Christoph U., Males, Jared R., Morzinski, Katie M., Close, Laird M., Codona, Johanan L., Hinz, Philip M., Hornburg, Kathryn J., Brickson, Leandra L., Escuti, Michael J. 12 January 2017 (has links)
We report on the performance of a vector apodizing phase plate coronagraph that operates over a wavelength range of 2-5 mu m. and is installed in MagAO/Clio2 at the 6.5 m Magellan Clay telescope at Las Campanas Observatory, Chile. The coronagraph manipulates the phase in the pupil to produce three beams yielding two coronagraphic point-spread functions (PSFs) and one faint leakage PSF. The phase pattern is imposed through the inherently achromatic geometric phase, enabled by liquid crystal technology and polarization techniques. The coronagraphic optic is manufactured using a direct-write technique for precise control of the liquid crystal pattern. and multitwist retarders for achromatization. By integrating a linear phase ramp to the coronagraphic phase pattern, two separated coronagraphic PSFs are created with a single pupil-plane optic, which makes it robust and easy to install in existing telescopes. The two coronagraphic PSFs contain a 180 degrees dark hole on each side of a star, and these complementary copies of the star are used to correct the seeing halo close to the star. To characterize the coronagraph, we collected a data set of a bright (m(L) = 0-1) nearby star with similar to 1.5 hr of observing time. By rotating and optimally scaling one PSF. and subtracting it from the other PSF, we see a contrast improvement by 1.46 magnitudes at 3.5 lambda/D. With regular angular differential imaging at 3.9 mu m, the MagAO vector apodizing phase plate coronagraph delivers a 5 sigma Delta mag contrast of 8.3 (= 10(-3.3)) at 2 lambda/D and 12.2 (= 10(-4.8)) at 3.5 lambda/D.
177

The F-22 Radar Instrumentation System

Natale, Louis, Roach, John 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada
178

The design of a fuzzy logic system for control of an unmanned aircraft

Assuncao, Jose Manuel Ventura January 1996 (has links)
Many control problems are based on control objectives easily quantified and consequently realisable by standard control synthesis methods. When an unmanned aircraft navigates, it moves inside a complex environment due to interactions with its surrounding and time varying environmental conditions. Several causes of perturbations have been identified as for example gusts and corrupted information of position. The characteristics of possible missions carried out by the un manned aircraft leads to the desire to construct navigation control systems which when operated in perturbed environments combine the advantages of smooth control with accurate navigation. Rule based, and adaptive controllers have favourable properties for such systems. This thesis investigates the use of a rule based navigation controller for a particular unmanned aircraft, the XRAEl aircraft. To achieve this objective several different types of fuzzy logic controllers are analysed as for example conventional and direct and indirect adaptive fuzzy controllers. They are designed by employing simple control engineering knowledge and subsequently validated using a stability method. For this purpose diverse stability methods are described and a new technique presented, the fuzzy root locus method, which is also based on the introduction of a new concept for fuzzy logic controllers, the fuzzy cell. The realisation of this work has been achieved by a series of simulation tests employing different processes and a simulation model of the XRAEl aircraft. The conclusions drawn from the results of the experiments consider in general that a rule based controller can improve the quality of navigation when compared to conventional controllers.
179

Hur trailermusik påverkar förväntningarna på ett spel : Effekterna och konsekvenserna av instrumentation i en spel-trailer / How trailer music affects the expectations of a game : The effects and consequences of the music choice in a game trailer

Wiesand, Arvid January 2017 (has links)
Trailers har använts för att förmedla filmer och spels budskap i snart ett århundrade. Denna studies syfte är att undersöka hur genre, upplevelse av spelmoment och känsla förändras mellan tre olika versioner av samma trailer. De två första versionerna innehåller symfonisk respektive elektronisk instrumentation och den tredje versionen endast ljudeffekter.En kvalitativ metod i form av semistrukturerade intervjuer användes för att ta fram deltagarnas svar och 12 personer i åldrarna 18 – 30 år deltog i studien. Fyra för varje version av trailer. Deltagarna fick först besvara en mindre enkät med grundläggande information. De fick sedan se en version av trailern och till sist delta i en intervju kring hur de upplevde genre, spelmoment och känsla.Undersökningen visade att instrumentationen och frånvaron av musik påverkade deltagarnas svar. Framtida forskning och vidare arbete är nödvändigt för att ta fram ett resultat med högre validitet.
180

A VERSATILE TECHNIQUE TO ENABLE SUB-MILLI-KELVIN INSTRUMENT STABILITY FOR PRECISE RADIAL VELOCITY MEASUREMENTS: TESTS WITH THE HABITABLE-ZONE PLANET FINDER

Stefansson, Gudmundur, Hearty, Frederick, Robertson, Paul, Mahadevan, Suvrath, Anderson, Tyler, Levi, Eric, Bender, Chad, Nelson, Matthew, Monson, Andrew, Blank, Basil, Halverson, Samuel, Henderson, Chuck, Ramsey, Lawrence, Roy, Arpita, Schwab, Christian, Terrien, Ryan 16 December 2016 (has links)
Insufficient instrument thermomechanical stability is one of the many roadblocks for achieving 10 cm s(-1) Doppler radial velocity precision, the precision needed to detect Earth-twins orbiting solar-type stars. Highly temperature and pressure stabilized spectrographs allow us to better calibrate out instrumental drifts, thereby helping in distinguishing instrumental noise from astrophysical stellar signals. We present the design and performance of the Environmental Control System (ECS) for the Habitable-zone Planet Finder (HPF), a high-resolution (R = 50,000) fiber-fed near-infrared (NIR) spectrograph for the 10 m Hobby-Eberly Telescope at McDonald Observatory. HPF will operate at 180 K, driven by the choice of an H2RG NIR detector array with a 1.7 mu m cutoff. This ECS has demonstrated 0.6 mK rms stability over 15 days at both 180 and 300 K, and maintained high-quality vacuum (< 10 (7) Torr) over months, during long-term stability tests conducted without a planned passive thermal enclosure surrounding the vacuum chamber. This control scheme is versatile and can be applied as a blueprint to stabilize future NIR and optical high-precision Doppler instruments over a wide temperature range from similar to 77 K to elevated room temperatures. A similar ECS is being implemented to stabilize NEID, the NASA/NSF NN-EXPLORE spectrograph for the 3.5 m WIYN telescope at Kitt Peak, operating at 300 K. A [full SolidWorks 3D-CAD model] and a comprehensive parts list of the HPF ECS are included with this manuscript to facilitate the adaptation of this versatile environmental control scheme in the broader astronomical community.

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