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2010

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Full-Text Articles in Engineering

Cloaked Near-Field Scanning Optical Microscope Tip For Noninvasive Near-Field Imaging, Andrea Alù, Nader Engheta Dec 2010

Cloaked Near-Field Scanning Optical Microscope Tip For Noninvasive Near-Field Imaging, Andrea Alù, Nader Engheta

Departmental Papers (ESE)

Near-field imaging is a well-established technique in biomedical measurements, since closer to the detail of interest it is possible to resolve subwavelength details otherwise unresolved by regular lenses. A near-field scanning optical microscope (NSOM) tip may indeed overcome the resolution limits of far-field optics, but its proximity inherently perturbs the measurement. Here, we apply the recent concept of a ‘‘cloaked sensor’’ to an NSOM device in collection mode, showing theoretically how a proper plasmonic cover applied to an NSOM tip may drastically improve its overall measurement capabilities.


Design Concepts Of Terahertz Quantum Cascade Lasers: Proposal For Terahertz Laser Efficiency Improvements, Tillmann Kubis, Saumitra Raj Mehrotra, Gerhard Klimeck Dec 2010

Design Concepts Of Terahertz Quantum Cascade Lasers: Proposal For Terahertz Laser Efficiency Improvements, Tillmann Kubis, Saumitra Raj Mehrotra, Gerhard Klimeck

Birck and NCN Publications

Conceptual disadvantages of typical resonant phonon terahertz quantum cascade lasers 􏰎THz-QCLs􏰍 are analyzed. Alternative designs and their combination within a concrete device proposal are discussed to improve the QCL performance. The improvements are 􏰎1􏰍 indirect pumping of the upper laser level, 􏰎2􏰍 diagonal optical transitions, 􏰎3􏰍 complete electron thermalization, and 􏰎4􏰍 materials with low effective electron masses. The nonequilibrium Green’s function method is applied to predict stationary electron transport and optical gain. The proposed THz-QCL shows a higher optical gain, a lower threshold current, and a higher operation temperature. Alloy disorder scattering can worsen the QCL performance.


An Integrated Approach For Phytate Degradation And Recovery Of Myo-Inositol And Phosphate As Valued-Added Products From The By-Products Of Corn Ethanol Industry, Jun Dang Dec 2010

An Integrated Approach For Phytate Degradation And Recovery Of Myo-Inositol And Phosphate As Valued-Added Products From The By-Products Of Corn Ethanol Industry, Jun Dang

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

An integrated process was developed to hydrolyze the phytates in light steep water (LSW) and to simultaneously isolate inorganic phosphate (Pi) and myo-inositol products. The proposed integrated process is helpful in resolving the environmental and nutritional concerns in the use of corn gluten feed (CGF) in the animal diets. This process comprised of partial and total hydrolysis of LSW and intermediate anion exchange separation technique. The phytates in LSW were initially degraded to negatively charged myo-inositol phosphates (InsP2 - InsP5). The optimized experimental parameters for the partial hydrolysis of LSW were determined to be 2 h hydrolysis with 1 ...


A High-Quality Mach-Zehnder Interferometer Fiber Sensor By Femtosecond Laser One-Step Processing, Longjiang Zhao, Lan Jiang, Sumei Wang, Hai Xiao, Yongfeng Lu, Hai-Lung Tsai Dec 2010

A High-Quality Mach-Zehnder Interferometer Fiber Sensor By Femtosecond Laser One-Step Processing, Longjiang Zhao, Lan Jiang, Sumei Wang, Hai Xiao, Yongfeng Lu, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

During new fiber sensor development experiments, an easy-to-fabricate simple sensing structure with a trench and partially ablated fiber core is fabricated by using an 800 nm 35 fs 1 kHz laser. It is demonstrated that the structure forms a Mach-Zehnder interferometer (MZI) with the interference between the laser light passing through the air in the trench cavity and that in the remained fiber core. The fringe visibilities are all more than 25 dB. The transmission spectra vary with the femtosecond (fs) laser ablation scanning cycle. The free spectral range (FSR) decreases as the trench length increases. The MZI structure is ...


Propulsive Force Measurements And Flow Behavior Of Undulatory Swimmers At Low Reynolds Number, Josué Sznitman, Xiaoning Shen, Raphael Sznitman, Paulo E. Arratia Dec 2010

Propulsive Force Measurements And Flow Behavior Of Undulatory Swimmers At Low Reynolds Number, Josué Sznitman, Xiaoning Shen, Raphael Sznitman, Paulo E. Arratia

Departmental Papers (MEAM)

The swimming behavior of the nematode Caenorhabditis elegans is investigated in aqueous solutions of increasing viscosity. Detailed flow dynamics associated with the nematode’s swimming motion as well as propulsive force and power are obtained using particle tracking and velocimetry methods. We find that C. elegans delivers propulsive thrusts on the order of a few nanonewtons. Such findings are supported by values obtained using resistive force theory; the ratio of normal to tangential drag coefficients is estimated to be approximately 1.4. Over the range of solutions investigated here, the flow properties remain largely independent of viscosity. Velocity magnitudes of ...


Integrated Freestanding Single-Crystal Silicon Nanowires: Conductivity And Surface Treatment, Chung-Hoon Lee, Clark Ritz, Minghuang Huang, Michael Ziwisky, Robert Blise, Max Lagally Dec 2010

Integrated Freestanding Single-Crystal Silicon Nanowires: Conductivity And Surface Treatment, Chung-Hoon Lee, Clark Ritz, Minghuang Huang, Michael Ziwisky, Robert Blise, Max Lagally

Electrical and Computer Engineering Faculty Research and Publications

Integrated freestanding single-crystal silicon nanowires with typical dimension of 100 nm × 100 nm × 5 µm are fabricated by conventional 1:1 optical lithography and wet chemical silicon etching. The fabrication procedure can lead to wafer-scale integration of silicon nanowires in arrays. The measured electrical transport characteristics of the silicon nanowires covered with/without SiO2 support a model of Fermi level pinning near the conduction band. The I–V curves of the nanowires reveal a current carrier polarity reversal depending on Si–SiO2 and Si–H bonds on the nanowire surfaces


Extraction Of Contact Resistance In Carbon Nanofiber Via Interconnects With Varying Lengths, Ken Li, Patrick Wilhite, Vinit Khera, Shoba Krishnan, Xuhui Sun, Cary Y. Yang Dec 2010

Extraction Of Contact Resistance In Carbon Nanofiber Via Interconnects With Varying Lengths, Ken Li, Patrick Wilhite, Vinit Khera, Shoba Krishnan, Xuhui Sun, Cary Y. Yang

Electrical and Computer Engineering

A method to extract the contact resistance and bulk resistivity of vertically grown carbon nanofibers (CNFs) or similar one-dimensional nanostructures is described. Using a silicon-compatible process to fabricate a terrace test structure needed for the CNF length variation, the contact resistance is extracted by measuring in situ the resistances of individual CNFs with different lengths and within a small range of diameters using a nanoprober inside a scanning electron microscope. Accurate determination of contact resistances for various combinations of catalysts and underlayer metals can lead to eventual optimization of materials’ growth and device fabrication processes for CNF via interconnects.


Effective Ionic Conductivity Of A Novel Intermediate-Temperature Mixed Oxide-Ion And Carbonate-Ion Conductor, Xue Li, Guoliang Xiao, Kevin Huang Dec 2010

Effective Ionic Conductivity Of A Novel Intermediate-Temperature Mixed Oxide-Ion And Carbonate-Ion Conductor, Xue Li, Guoliang Xiao, Kevin Huang

Faculty Publications

A systematic investigation on the effective ionic conductivity (σm) of a novel intermediate-temperature mixed oxide-ion and carbonate-ion conductor MOCC consisting of a ceria phase and a carbonate phase is reported. The study explicitly shows that the observed remarkable temperature-dependent σm is primarily the result of softening/melting of the carbonate phase as the physical state of the carbonate phase transforms from solid, softened to molten. Differential scanning calorimetry analysis complements the understanding of the observed electrical behavior by revealing temperatures of melting and solidification in agreement with the onset temperatures of σm. In addition, the measured σ ...


Spectrum Auction Framework For Access Allocation In Cognitive Radio Networks, Guarav S. Kasbekar, Saswati Sarkar Dec 2010

Spectrum Auction Framework For Access Allocation In Cognitive Radio Networks, Guarav S. Kasbekar, Saswati Sarkar

Departmental Papers (ESE)

In cognitive radio networks, there are two categories of networks on different channels: primary networks, which have high-priority access, and secondary networks, which have low-priority access. We develop an auction-based framework that allows networks to bid for primary and secondary access based on their utilities and traffic demands. The bids are used to solve the access allocation problem, which is that of selecting the primary and secondary networks on each channel either to maximize the auctioneer’s revenue or to maximize the social welfare of the bidding networks, while enforcing incentive compatibility. We first consider the case when the bids ...


Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang Dec 2010

Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang

Civil and Environmental Engineering Theses, Dissertations, and Student Research

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures were collected at the time of paving and were transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of ...


Critical Analysis On The Structural And Magnetic Properties Of Bulk And Nanocrystalline Cu-Fe-O, D. Paul Joseph, C. Venkateswaran, R. Selva Vennila Dec 2010

Critical Analysis On The Structural And Magnetic Properties Of Bulk And Nanocrystalline Cu-Fe-O, D. Paul Joseph, C. Venkateswaran, R. Selva Vennila

Center for Study of Matter at Extreme Conditions

Nanocrystalline and bulk samples of “Fe”-doped CuO were prepared by coprecipitation and ceramic methods. Structural and compositional analyses were performed using X-ray diffraction, SEM, and EDAX. Traces of secondary phases such as CuFe2O4, Fe3O4, and α-Fe2O3 having peaks very close to that of the host CuO were identified from the Rietveld profile analysis and the SAED pattern of bulk and nanocrystalline Cu0.98Fe0.02O samples. Vibrating Sample Magnetometer (VSM) measurements show hysteresis at 300 K for all the samples. The ferrimagnetic Neel transition temperature () was found ...


The Wireless Control Network: Synthesis And Robustness, Miroslav Pajic, Shreyas Sundaram, Jerome Le Ny, George J. Pappas, Rahul Mangharam Dec 2010

The Wireless Control Network: Synthesis And Robustness, Miroslav Pajic, Shreyas Sundaram, Jerome Le Ny, George J. Pappas, Rahul Mangharam

Real-Time and Embedded Systems Lab (mLAB)

We consider the problem of stabilizing a plant with a network of resource constrained wireless nodes. Traditional networked control schemes are designed with one of the nodes in the network acting as a dedicated controller, while the other nodes simply route information to and from the controller and the plant. We introduce the concept of a Wireless Control Network (WCN) where the entire network itself acts as the controller. Specifically, at each time-step, each node updates its internal state to be a linear combination of the states of the nodes in its neighborhood. We show that this causes the entire ...


The Wireless Control Network: Monitoring For Malicious Behavior, Shreyas Sundaram, Miroslav Pajic, Christoforos N. Hadjicostis, Rahul Mangharam, George J. Pappas Dec 2010

The Wireless Control Network: Monitoring For Malicious Behavior, Shreyas Sundaram, Miroslav Pajic, Christoforos N. Hadjicostis, Rahul Mangharam, George J. Pappas

Real-Time and Embedded Systems Lab (mLAB)

We consider the problem of stabilizing a plant with a network of resource constrained wireless nodes. In a companion paper, we developed a protocol where each node repeatedly transmits a linear combination of the values in its neighborhood. For certain topologies, we showed that these linear combinations can be designed so that the closed loop system is stable (i.e., the wireless network itself acts as a controller for the plant). In this paper, we design a Intrusion Detection System (IDS) for this control scheme, which observes the transmissions of certain nodes in the network and uses that information to ...


Universality Of Non-Ohmic Shunt Leakage In Thin-Film Solar Cells, Sourabh Dongaonkar, J. D. Servaites, G. M. Ford, S. Loser, R. M. Gelfand, H. Mohseni, Hugh Hillhouse, R. Agrawal, M. A. Ratner, T. J. Marks, Mark S. Lundstrom, Muhammad A. Alam Dec 2010

Universality Of Non-Ohmic Shunt Leakage In Thin-Film Solar Cells, Sourabh Dongaonkar, J. D. Servaites, G. M. Ford, S. Loser, R. M. Gelfand, H. Mohseni, Hugh Hillhouse, R. Agrawal, M. A. Ratner, T. J. Marks, Mark S. Lundstrom, Muhammad A. Alam

Other Nanotechnology Publications

We compare the dark current-voltage (IV) characteristics of three different thin-film solar cell types: hydrogenated amorphous silicon (a-Si:H) p-i-n cells, organic bulk heterojunction (BHJ) cells, and Cu(In, Ga)Se-2 (CIGS) cells. All three device types exhibit a significant shunt leakage current at low forward bias (V < similar to 0.4) and reverse bias, which cannot be explained by the classical solar cell diode model. This parasitic shunt current exhibits non-Ohmic behavior, as opposed to the traditional constant shunt resistance model for photovoltaics. We show here that this shunt leakage (I-sh), across all three solar cell types considered, is characterized by the following common phenomenological features: (a) voltage symmetry about V = 0, (b) nonlinear (power law) voltage dependence, and (c) extremely weak temperature dependence. Based on this analysis, we provide a simple method of subtracting this shunt current component from the measured data and discuss its implications on dark IV parameter extraction. We propose a space charge limited (SCL) current model for capturing all these features of the shunt leakage in a consistent framework and discuss possible physical origin of the parasitic paths responsible for this shunt current mechanism. (C) 2010 American Institute of Physics. [doi:10.1063/1.3518509]


Testing Embedded System Applications, Tingting Yu Dec 2010

Testing Embedded System Applications, Tingting Yu

Computer Science and Engineering: Theses, Dissertations, and Student Research

Embedded systems are becoming increasingly ubiquitous, controlling a wide variety of popular and safety-critical devices. Testing is the most commonly used method for validating software systems, and effective testing techniques could be helpful for improving the dependability of these systems. However, there are challenges involved in developing such techniques. Embedded systems consist of layers of software – application layers utilize services provided by underlying system service and hardware support layers. A typical embedded application consists of multiple user tasks. Interactions between application layers and lower layers, and interactions between the various user tasks that are initiated by the application layer, can ...


Optimal Pulse Width Modulation For Sinusoidal Fringe Generation With Projector Defocusing, Yajun Wang, Song Zhang Dec 2010

Optimal Pulse Width Modulation For Sinusoidal Fringe Generation With Projector Defocusing, Yajun Wang, Song Zhang

Mechanical Engineering Publications

Recently, a study showed that generating sinusoidal fringe patterns by properly defocusing binary ones can significantly simplify three-dimensional shape measurement system development and drastically improve its speed. However, when the fringe stripes are very wide, it is very difficult for this technique to achieve high-quality measurement. This Letter presents a method to improve this technique by selectively eliminating high-frequency harmonics induced by a squared binary pattern. As a result, better sinusoidal fringe patterns can be generated with a small degree of defocusing even for wide fringe stripes. Simulation and experiments will be presented to verify the performance of this proposed ...


Incorporating Feedback From Multiple Sensory Modalities Enhances Brain–Machine Interface Control, Aaron J. Suminski, Dennis C. Tkach, Andrew H. Fagg, Nicholas G. Hatsopoulos Dec 2010

Incorporating Feedback From Multiple Sensory Modalities Enhances Brain–Machine Interface Control, Aaron J. Suminski, Dennis C. Tkach, Andrew H. Fagg, Nicholas G. Hatsopoulos

Biomedical Engineering Faculty Research and Publications

The brain typically uses a rich supply of feedback from multiple sensory modalities to control movement in healthy individuals. In many individuals, these afferent pathways, as well as their efferent counterparts, are compromised by disease or injury resulting in significant impairments and reduced quality of life. Brain–machine interfaces (BMIs) offer the promise of recovered functionality to these individuals by allowing them to control a device using their thoughts. Most current BMI implementations use visual feedback for closed-loop control; however, it has been suggested that the inclusion of additional feedback modalities may lead to improvements in control. We demonstrate for ...


The Effects Of Electricity Pring On Phev Competitiveness, Shisheng Huang, Bri-Mathias S. Hodge, Farzad Taheripour, Joseph F. Pekny, Gintaras V. Reklaitis, Wallace E. Tyner Dec 2010

The Effects Of Electricity Pring On Phev Competitiveness, Shisheng Huang, Bri-Mathias S. Hodge, Farzad Taheripour, Joseph F. Pekny, Gintaras V. Reklaitis, Wallace E. Tyner

PPRI Digital Library

Plug-in Hybrid Electric Vehicles (PHEVs) will soon start to be introduced into the transportation sector, thereby raising a host of issues related to their use, adoption and effects on the electricity sector. Their introduction has the potential to significantly reduce carbon emissions from the transportation sector, which has led to government policies aimed at easing their introduction. If their wide-spread adoption is set as a target it is imperative to consider the effects of existing policies that may increase or decrease their adoption rate. In this study, we present a micro level electricity demand model that can gauge the effects ...


Design Of S-Band Transition Based On Microstrip Quarter-Wave Transformers, Bashir Souid, Josh Merchant, Michael Rice, Mahmoud El Sabbagh Dec 2010

Design Of S-Band Transition Based On Microstrip Quarter-Wave Transformers, Bashir Souid, Josh Merchant, Michael Rice, Mahmoud El Sabbagh

Electrical Engineering and Computer Science

In this technical report, the design of a high-frequency matching circuit is presented. This circuit is a transformer comprising a cascade of multisections of quarter-wavelength transmission lines. The transformer, also referred to as matching circuit, is implemented based on microstrip technology. The matching circuit is required to perform as a transition from a 10-Ω load to a 50-Ω source. Moreover, this transition is specified to have a return loss more than 20 dB over the entire S-band from 2 GHz to 4 GHz. Analytical model developed and verified by full-wave simulation results indicates that the design of a quarter-wavelength transformer ...


Can An Electric Field Induce An Antiferroelectric Phase Out Of A Ferroelectric Phase?, Xiaoli Tan, Cheng Ma, Wook Jo, J. Rödel Dec 2010

Can An Electric Field Induce An Antiferroelectric Phase Out Of A Ferroelectric Phase?, Xiaoli Tan, Cheng Ma, Wook Jo, J. Rödel

Materials Science and Engineering Publications

It has been widely accepted that electric fields favor the ferroelectric phase with parallel electric dipoles over the antiferroelectric phase. With detailed measurements in polycrystalline ceramics of Pb0.99Nb0.02[(Zr0.57Sn0.43)1-yTiy]0.98O3, we demonstrate in this Letter that electric fields can induce an antiferroelectric phase out of a ferroelectric phase, i.e., trigger an apparently unlikely ferroelectric-to-antiferroelectric phase transition. We suggest that it is caused by the volume contraction from the converse piezoelectric effect at the coercive field with a reversed polarity.


Optimization Strategy For Resonant Mass Sensor Design In The Presence Of Squeeze Film Damping, Chengzhang Li, Michele H. Miller Dec 2010

Optimization Strategy For Resonant Mass Sensor Design In The Presence Of Squeeze Film Damping, Chengzhang Li, Michele H. Miller

Michigan Tech Publications

This paper investigates the design optimization of an electrostatically actuated microcantilever resonator that operates in air. The nonlinear effects of electrostatic actuation and air damping make the structural dynamics modeling more complex. There is a need for an efficient way to simulate the system behavior so that the design can be more readily optimized. This paper describes an efficient analytical approach for determining the optimum design for a microcantilever resonant mass sensor. One simple case is described. The sensor design is a square plate that is coated with a functional polymer and attached to the substrate with folded leg springs ...


Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa Dec 2010

Paranets: A Parallel Network Architecture For The Future Internet, Khaled Harras, Abderrahmen Mtibaa

UMSL Faculty Works

The evolution of networking technologies and portable devices has led users to expect connectivity anytime and everywhere. We have reached the point of seeing networking occur underwater, via aerial devices, and across space. While researchers push the true boundaries of networking to serve a wide range of environments, there is the challenge of providing robust network connectivity beyond the boundaries of the core internet, defined by fiber optics and well-organized backbones. As the internet edges expand, the expectation is that connectivity will be as good, in terms of high bandwidth and minimal interruption, as anywhere in the core. Such an ...


Real-Time 3d Markerless Multiple Hand Detection And Tracking For Human Computer Interaction Applications, Soumita Ghosh, Jianmin Zheng, Wenyu Chen, Jane Zhang, Yiyu Cai Dec 2010

Real-Time 3d Markerless Multiple Hand Detection And Tracking For Human Computer Interaction Applications, Soumita Ghosh, Jianmin Zheng, Wenyu Chen, Jane Zhang, Yiyu Cai

Electrical Engineering

In this paper we present a purely vision based implementation of markerless hand detection and tracking system which effectively detects and tracks the hand positions irrespective of hand orientation. A shape based detection algorithm using a new line approximation technique followed by an adaptive minimum distance classifier based tracking technique is implemented. The technique is very generic and can be practically used in all types of immersive and semi-immersive environments like simulations, three-dimensional (3D) games, visually assisted medical surgery and other humancomputer interactive applications.


2d Motion Detection Bounded Hand 3d Trajectory Tracking And Gesture Recognition Under Complex Background, Shuangqing Wu, Yin Zhang, Sanyuan Zhang, Xiuzi Ye, Yiyu Cai, Jianmin Zheng, Soumita Ghosh, Wenyu Chen, Jane Zhang Dec 2010

2d Motion Detection Bounded Hand 3d Trajectory Tracking And Gesture Recognition Under Complex Background, Shuangqing Wu, Yin Zhang, Sanyuan Zhang, Xiuzi Ye, Yiyu Cai, Jianmin Zheng, Soumita Ghosh, Wenyu Chen, Jane Zhang

Electrical Engineering

In this paper, a 2D motion detection bounded hand 3D trajectory tracking and gesture recognition system is proposed for virtual reality interactions. First, the Bayes decision rule for classification of background and foreground is utilized to automatically locate the hand that bounded within a rectangle, and then the trajectory of the hand in 3D space is tracked by mean shift particle filter and stereo imaging. The skin color feature is exploited for image matting that effectively segment the hand contour in video sequence automatically. Finally the hand gesture is recognized by the connected component analysis and line approximation.


Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez Dec 2010

Modeling Heat Transfer During Cooling Of Ready-To-Eat Meat And Poultry Products Using Three-Dimensional Finite Element Analysis And Web-Based Simulation, Jihan F. Cepeda Jimenez

Biological Systems Engineering--Dissertations, Theses, and Student Research

The meat industry is required to comply with processing performance standards for preventing the growth of foodborne pathogens in products. These performance standards, established by the United States Department of Agriculture - Food Safety and Inspection Service (USDA-FSIS) require a reduction of Salmonella spp (lethality standard) and limit the growth of sporeforming bacteria (stabilization standard) in certain processed meat products. In general, strategies used to comply with these standards are associated with thermal processing. Meat processors have difficulties complying with these performance standards. Moreover, thermal processing deviations are an issue in the meat industry that generate uncertainty regarding the safety of ...


In Situ Observation Of Antisite Defect Formation During Crystal Growth, Matthew J. Kramer, Mikhail I. Mendelev, Ralph E. Napolitano Dec 2010

In Situ Observation Of Antisite Defect Formation During Crystal Growth, Matthew J. Kramer, Mikhail I. Mendelev, Ralph E. Napolitano

Materials Science and Engineering Publications

In situ x-ray diffraction (XRD) coupled with molecular dynamics (MD) simulations have been used to quantify antisite defect trapping during crystallization. Rietveld refinement of the XRD data revealed a marked lattice distortion which involves an a axis expansion and a c axis contraction of the stable C11b phase. The observed lattice response is proportional in magnitude to the growth rate, suggesting that the behavior is associated with the kinetic trapping of lattice defects. MD simulations demonstrate that this lattice response is due to incorporation of 1% to 2% antisite defects during growth.


Moving Ground Target Tracking In Urban Terrain Using Air/Ground Vehicles, Timothy Mclain, Randal W. Beard, Mark Owen, Huili Yu Dec 2010

Moving Ground Target Tracking In Urban Terrain Using Air/Ground Vehicles, Timothy Mclain, Randal W. Beard, Mark Owen, Huili Yu

Faculty Publications

In this paper, we present a framework for tracking a moving target in urban environments using UAVs in cooperation with UGVs. The framework takes into account occlusions between the sensor and the target. The target state is modeled using the dynamic occupancy grid and the target motion model is built using a second-order Markov chain. Based on the target occupancy grid, we design the path planning algorithm to maneuver the UAV and the UGV to configurations where they can detect the target with high probability. Simulation results show the framework is successful in solving the target tracking problem in urban ...


Automatic Media Segmentation Within Ieee 1599–2008, Antonello D'Aguanno, Luca A. Ludovico, Davide Andrea Mauro Dec 2010

Automatic Media Segmentation Within Ieee 1599–2008, Antonello D'Aguanno, Luca A. Ludovico, Davide Andrea Mauro

Computer Sciences and Electrical Engineering Faculty Research

This paper deals with the automatic extraction of synchronization data from IEEE 1599-2008, an XML-based standard aiming at a comprehensive description of music. Within such format, audio tracks and video contents related to the same music piece can be referred to the occurrence of symbolic music events. In this way, digital objects are mutually synchronized, too. The goal is to show how timing information can be easily extracted from an IEEE 1599-2008 file, converted into a suitable format, and finally employed in a multimedia editing environment in order to produce an automatic segmentation of media objects.


Process To Produce High Surface Area Nanoparticle Vanadium Phosphorus Oxide Catalyst And Product Derives Thereof, Yun Hin Taufiq-Yap, Ali A. Rownaghi Dec 2010

Process To Produce High Surface Area Nanoparticle Vanadium Phosphorus Oxide Catalyst And Product Derives Thereof, Yun Hin Taufiq-Yap, Ali A. Rownaghi

Chemical and Biochemical Engineering Faculty Research & Creative Works

An improved process to produce high surface area nanoparticle vanadium phosphorus oxide catalysts comprises the steps of reducing vanadium-containing compounds in an alcohol solution selected from the group consisting of isobutanol and benzyl alcohol and any combination derives thereof under reflux for 4 to 6 hours to form a suspended mixture; reacting dopants and phosphorus-containing compounds to the suspended mixture under reflux for 30 minutes to 3 hours to form precursors of the vanadium phosphorus oxide catalysts; drying the formed precursors; and calcining the dried precursors in a flow of gaseous n-butane/air mixture at 400 to 460° C. to ...


Theory And Applications Of Compressive Sensing, Atul Divekar, Okan Ersoy Dec 2010

Theory And Applications Of Compressive Sensing, Atul Divekar, Okan Ersoy

Department of Electrical and Computer Engineering Technical Reports

This thesis develops algorithms and applications for compressive sensing, a topic in signal processing that allows reconstruction of a signal from a limited number of linear combinations of the signal. New algorithms are described for common remote sensing problems including superresolution and fusion of images. The algorithms show superior results in comparison with conventional methods. We describe a method that uses compressive sensing to reduce the size of image databases used for content based image retrieval. The thesis also describes an improved estimator that enhances the performance of Matching Pursuit type algorithms, several variants of which have been developed for ...