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Broadband beamforming and direction finding using concentric ring array
(University of Missouri--Columbia, 2005)
Sensor arrays have been used widely in applications including radar, sonar, seismology, biomedicine, communications and imaging. A very popular type of sensor array is circular array, which has almost invariant array pattern in azimuthal plane...
Fully automated deep supervised and unsupervised learning approaches for 3D protein cryo-EM density map reconstruction
(University of Missouri--Columbia, 2019)
of single particle images are required to be extracted from two-dimensional (2D) cryo-electron microscopy (cryo-EM) to build a reliable high-resolution (3D) model. In order to reduce the radiation damage to the biomolecules of interest during the imaging...
Single carrier frequency domain equalization for broadband wireless communications
(University of Missouri--Columbia, 2007)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This thesis discusses different channel estimation techniques, channel equalization and various diversity schemes for broadband wireless communication ...
Decadal mass balance of the Antarctic ice sheet from satellite radar altimetry and its contribution to global sea level change
(University of Missouri--Columbia, 2006)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In this research, we estimated the decadal mass balance of the Antarctic ice sheet using the European Space Agency's ERS-1 and ERS-2 satellite radar ...
Magnetoresistance in semiconductor-metal hybrids for power applications
(University of Missouri--Columbia, 2008)
. Current concentration caused by the inclusion of a shunt was found to limit the pulsed current capacity in each device studied. For a common scale (13.6 mm x 3.4 mm x 1 mm), pulsed-current capacity was found to vary within each device topology according...
Synthesis and characterization of TiO2 nanotube Schottky diodes
(University of Missouri--Columbia, 2021)
, nonstoichiometric TiO2 diodes displayed an improved ideality factor from 3.7 to 2.4. A 350 [degrees] C post-fabrication thermal treatment, however, led to both stoichiometric and nonstoichiometric TiO2 diodes having similar ideality factors of 2.0 and similar shifts...
Land cover classification from satellite imagery, and its applications in cellular network planning
(University of Missouri--Columbia, 2005)
techniques were applied to Radarsat data at various windows from 3 x 3 to 25 x 25 pixels. For a single radar feature, the Entropy processing at window size 13 x 13 provides the best overall land cover classification accuracy improvement when fused...
Metasurface based uncooled Sixgeyo1-x-y microbolometer for infrared detection
(University of Missouri--Columbia, 2022)
on the geometry of the metasurface material. The inclusion of the metasurface permits engineering the IR absorptance with respect to wavelength. Absorption by the metasurface eliminates the need for a 1/4-wave resonant cavity under the microbolometer. In addition...
Localization in challenging environment using geometric and machine learning techniques
(University of Missouri--Columbia, 2019)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] The establishment of robust sensor network applications requires accurate and non complex positioning techniques using a full or partial set of ...
Adaptive array signal processing using the concentric ring array and the spherical array
(University of Missouri--Columbia, 2009)
This thesis introduces new methods for partial adaptive beamforming using concentric ring and spherical arrays for acoustic signals on a partially known interference environment. We propose novel methods to choose intra-ring ...
Bayesian approach for the spectrum sensing mimo-cognitive radio network with presence of the uncertainty
(University of Missouri--Columbia, 2021)
A cognitive radio technique has the ability to learn. This system not only can observe the surrounding environment, adapt to environmental conditions, but also efficiently use the radio spectrum. This technique allows the ...
Moving object localization using frequency measurements
(University of Missouri--Columbia, 2021)
This research investigates the ability of locating a moving object using the Doppler shifts of a carrier frequency signal sent or re ected by the object and observed by several fixed or moving sensors spatially distributed in the 2-D or 3-D space...
Impedance and plasmonic based MEMS sensors for chemical and biological applications
(University of Missouri--Columbia, 2020)
that increased the strength of the measured signal by a factor between 4 and 6.25, high sensitivity of 3 cell/ml and detection time of less than 1 hour. The second project is implementing a fiber optic based chemical sensor, which consists of a thin film metal...
Metasurface integrated uncooled silicon germanium oxide microbolometers for long wavelength infrared detection
(University of Missouri--Columbia, 2022)
-noise is dominant at low frequencies. The corresponding 1/f-noise coefficients Kf for the devices that were annealed in vacuum and forming gases were changed from 3.26x10-10 to 2.375x10-14 and from 2.435x10-11 to 7.078x10-14 after 4 hours of annealing at 300 degrees...
Investigation of a spatial optical pulse collection system in the all-optical analog-to-digital converter
(University of Missouri--Columbia, 2005)
In this research, I conducted a systematic integration of specific calculations for the analysis of the spatial filter that is a critical component of an all-optical analog-to-digital converter. The designed all-optical ...
MSM photodiode as the switching element in a photoswitch-based class E microwave power amplifier
(University of Missouri--Columbia, 2008)
A photoswitch is designed for use as the switching element in a 2 GHz class E amplifier. The application of this amplifier is as the final-stage amplifier in the transmit-receive module of a phased-array radar system. The ...
Simulation and experimental study of the multichanneling rimfire gas switch
(University of Missouri--Columbia, 2005)
Since 1985, the Rimfire switch has been used extensively in accelerators at Sandia National Laboratories. Demands for increased future accelerator performance require improvements to the Rimfire switch. This thesis is both ...
Clustering in relational data and ontologies
(University of Missouri--Columbia, 2010)
This dissertation studies the problem of clustering objects represented by relational data. This is a pertinent problem as many real-world data sets can only be represented by relational data for which object-based clustering ...
Case study of normal and high glucose laden cell response to cellular phone radiation using GTEM cell
(University of Missouri--Columbia, 2012)
; the frequencies and power respectively represent radiations from a hand held cell phone and the cell phone tower. The simulated return loss and the VSWR values cell from 0 to 4.0 GHz for the GTEM are > 10 dB and < 2, respectively and provided perfect conditions...
Optimum receiver design and performance analysis for wireless communication
(University of Missouri--Columbia, 2005)
This dissertation is devoted to the optimum receiver design and theoretical performance analysis of wireless communication systems operated over fading channels, and this objective is incarnated by means of design, analysis ...