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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.
31

BLAST: A Balloon-borne, Large-aperture, Submillimetre Telescope

Wiebe, Donald Victor 26 February 2009 (has links)
BLAST is a balloon-borne large-aperture, submillimetre telescope, which makes large area (1-200 square degree) surveys of Galactic and extragalactic targets. Since BLAST observes in the stratosphere, it is able to make broad-band observations between 200um and 550um which are difficult or impossible to perform from the ground. BLAST has been designed to probe star formation both in the local Galaxy and in the high redshift (z=1-4) universe. Because BLAST is flown on an unmanned stratospheric balloon platform, it has been designed to be able to operate autonomously, without needing operator intervention to perform its scientific goals. This thesis includes an overview of the design of the BLAST platform, with emphasis on the command and control systems used to operate the telescope. BLAST has been flown on two long-duration balloon flights. The first of these, from Esrange, Sweden in June of 2005, acquired ~70 hours of primarily Galactic data. During the second flight, from Willy Field, Antarctica in December of 2006, BLAST acquired ~225 hours of both Galactic and extragalactic data. Operational performance of the platform during these two flights is reviewed, with the goal of providing insight on how future flights can be improved. Reduction of the data acquired by these large-format bolometer arrays is a challenging procedure, and techniques developed for BLAST data reduction are reviewed. The ultimate goal of this reduction is the generation of high quality astronomical maps which can be used for subsequent portions of data analysis. This thesis treats, in detail, the iterative, maximum likelihood map maker developed for BLAST. Results of simulations performed on the map maker to characterise its ability to reconstruct astronomical signals are presented. Finally, astronomical maps produced by this map maker using real data acquired by BLAST are presented, with a discussion on non-physical map pathologies resulting from the data reduction pipeline and map making procedures.
32

Wireless, automated monitoring for potential landslide hazards

Garich, Evan Andrew 17 September 2007 (has links)
This thesis describes research efforts toward the development of a wireless sensor node, which can be employed in durable and expandable wireless sensor networks for remote monitoring of soil conditions in areas conducive to slope stability failures. Commercially available soil moisture probes and soil tilt sensors were combined with low-power, wireless data transmitters to form a self-configuring network of soil monitoring sensors. The remote locations of many slope stability hazard sites eliminates the possibility of real-time, remote monitoring instrumentation that relies on AC power or land-based communication methods for operation and data transfer. Therefore, various power supply solutions and data transfer methods were explored during this research and are described herein. Additionally, sensor modification and calibrations are discussed. Preliminary evaluations of field durability of the pilot instrumentation were undertaken during this research. Geotechnical engineering instrumentation must be able to withstand extreme weather related conditions. The wireless, solar-powered soil moisture and tilt sensor node was installed on the Texas A&M University campus, allowing evaluation of system reliability and instrument durability. Lastly, potential future research and conclusions arising from this research are presented. This research has shown that commercially available wireless instrumentation can be modified for use in geotechnical applications. The development of an active power management system allows for sensors to be placed in remote locations and operated indefinitely, thus creating another option for monitoring applications in geotechnical and environmental problems.
33

Gustav Mahlers Klangwelt : Studien zur Instrumentation /

Ünlü, Altug, January 1900 (has links)
Dissertation--Hamburg--Universität, 2005. / Bibliogr. p. 263-275. Index.
34

Jean-Georges Kastner's Traité général d'instrumentation a translation and commentary /

Woodward, Patricia Jovanna. Kastner, Georges, January 2003 (has links)
Thesis (M.M.)--University of North Texas, 2003. / Includes bibliographical references (p. 316-317).
35

Admittance measurement for assessment of cardiac hemodynamics in clinical and research applications

Larson, Erik Rist 10 July 2014 (has links)
The admittance method is an important tool for the indirect determination of cardiac hemodynamics in animal research and has clinical potential as a hemodynamic monitor for implantable cardioverter-defibrillators (ICDs). Animal studies use a conductance catheter to determine left-ventricular (LV) volume, but ICDs must make use of existing pacing leads to perform an admittance measurement. This work aims to further the use of the admittance method by extending its use to multi-segment conductance catheters, determining parasitic circuit element's effects on electric property measurements, using biventricular pacing leads to determine cardiac hemodynamics, and analysis of spatial sensitivity using finite element models in various configurations. Experimental results show the admittance method can be used to determine LV stroke volume with biventricular pacing leads. Modeling results show removal of the muscle component focuses the measurement's spatial sensitivity towards the left-ventricular blood pool. / text
36

A Current Balancing Instrumentation Amplifier (CBIA) Bioamplifier with High Gain Accuracy

Dwobeng, Ebenezer 2011 December 1900 (has links)
Electrical signals produced in the human body can be used for medical diagnosis and research, treatment of diseases, pilot safety etc. These signals are extracted using an electrode (or transducer) to convert the ion current in the body to electron current. After the electrode, the very low amplitude extracted signal is amplified by an analog frontend that typically consists of an instrumentation amplifier (IA), a programmable gain amplifier (PGA), and a low pass filter (LPF). The output of the analog frontend is converted to digital signal by an analog to digital converter (ADC) for subsequent processing in the digital domain. This thesis discusses the circuit design challenges of the analog frontend instrumentation amplifier, compares existing circuit topologies used to implement the IA and proposes a new frontend IA. The proposed circuit uses the Current Balancing Instrumentation Amplifier (CBIA) topology to achieve high gain accuracy over a wide range of the output impedance. In addition it uses common circuit design techniques such as chopper modulation to achieve low flicker noise corner frequency, high common mode rejection (CMRR) and low noise efficiency factor (NEF). The proposed circuit has been implemented in the 0.5um CMOS ON-semiconductor process and consumes 16uW of power. The post-layout simulated gain accuracy is better than 94% for gain values from 20dB to 60dB, measured NEF is 7.8 and CMRR is better than 100dB.
37

Form and orchestration in the pre-classical symphony,

Stedman, William Preston, January 1953 (has links)
Thesis (Ph. D.)--University of Rochester, 1953. / Typescript and manuscript. Vol. 2: Supplement, comprising: transcriptions of works by Giuseppe Matteo Alberti (Concerto XII), Thomas Arne ([Overtures, no. 2]), Johann Wenzel Anton Stamitz (Simphonia a quatro stromenti), Anton Filtz (Synphonia a due violini, viola è basso), Anton Wilhelm Solnitz ([Symphonies, 2 violins, viola & bass, op. 3 no. 6, E-flat major]), and Karl Friedrich Abel ([Symphony, K. 3, D major]); "Examples" cited in the text of the thesis, and "thematic index" of musical examples. Bibliography: v. 1, leaves 163-182. Digitized version available online via the Sibley Music Library, Eastman School of Music http://hdl.handle.net/1802/5419
38

Klangdramaturgie Studien zur theatralen Orchesterkomposition in Wagners "Ring des Nibelungen"

Janz, Tobias January 2005 (has links)
Zugl.: Berlin, Humboldt-Univ., Diss., 2005
39

Transurethral microwave thermotherapy of benign prostatic hyperplasia : a clinical and methodological evaluation /

Hallin, Anders, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.
40

The successful use of percussion in the modern orchestra as exemplified by three works of Rogers, Stravinsky, and Bartók--with appended recording.

Frazeur, T. C. January 1956 (has links)
Thesis (M.M.)--University of Rochester, 1956. / Appendix: l. 179. Tape recording inserted in pocket. Bibliography: l. 180-182. Digitized version available online via the Sibley Music Library, Eastman School of Music (sound recording not in included) http://hdl.handle.net/1802/2374

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