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Deconvolution Of Ultrasonic Signals In Porous Materials: Estimation Of Acoustic Propagation Parameters Andwave Separation., Nizar Bouhlel, Sébastien Bourguignon 2016 Ecole Centrale de Nantes

Deconvolution Of Ultrasonic Signals In Porous Materials: Estimation Of Acoustic Propagation Parameters Andwave Separation., Nizar Bouhlel, Sébastien Bourguignon

Review of Progress in Quantitative Nondestructive Evaluation

Our study focuses on the development of assessment tools and nondestructive evaluation of porous materials from ultrasonic measurements. These materials are encountered in many industrial applications such as polyurethane foam used for insulation, aluminum foams used in aerospace or cancellous bone for biological applications. Acoustic propagation in these complex heterogeneous materials is governed by the Biot theory [1], involving the propagation of two types of waves: slow and fast wave, whose properties are respectively related to the fluid and solid phases constituting the material. During the propagation, these waves undergo deformations that can be characterized by related propagation models [2 ...


Low Frequency Ultrasonic Array Imaging Using Signal Post-Processing For Concrete Material, Akio Ozawa, Hideki Izumi, Kazuyuki Nakahata, Katsumi Ohira, Kenzo Ogawa 2016 Ehime University

Low Frequency Ultrasonic Array Imaging Using Signal Post-Processing For Concrete Material, Akio Ozawa, Hideki Izumi, Kazuyuki Nakahata, Katsumi Ohira, Kenzo Ogawa

Review of Progress in Quantitative Nondestructive Evaluation

The use of ultrasonic arrays for conducting non-destructive evaluation has been drastically increased in recent years. As one of the array imaging, a post-processing beam-forming technique has been proposed that utilizes a complete set of signals of all combinations of transmission and reception elements. This approach is referred to as full matrix capture (FMC) [1]. In FMC, each array element is sequentially used as an emitter and all other array elements are used as receivers. By changing the emitting element, we obtained a set of flaw signals that was used to form the focal beam. The delay-and-sum beam reconstruction based ...


Coded Sequences For Low Power Pulse Echo Systems, Julio Isla-Garcia, Frederic Cegla 2016 Imperial College London

Coded Sequences For Low Power Pulse Echo Systems, Julio Isla-Garcia, Frederic Cegla

Review of Progress in Quantitative Nondestructive Evaluation

There are many ultrasound applications where power is limited and as a result signals with low signal to noise ratio (SNR) are produced, electromagnetic-acoustic transducers (EMATs) and air coupled transducers being some examples. In those cases the SNR can be increased by averaging or pulse compression techniques. However, averaging is often lengthy because of the long wait periods required for the signals to die out in-between subsequent transmissions. Pulse compression, such as coded sequences, permits a more rapid injection of energy into the medium. Longer sequences mean a higher SNR can be realised; however, the length of the sequence is ...


Rapid Optical Ptychographic Prototyping With Broad Bandwidth Illumination, Jonathan T. Reichanadter 2016 University of Colorado, Boulder

Rapid Optical Ptychographic Prototyping With Broad Bandwidth Illumination, Jonathan T. Reichanadter

Undergraduate Honors Theses

The focus of the experiment is to construct an optical CDI microscope for rapid prototype development of techniques and algorithms for multicolor experiments. CDI is often accomplished using a monochromatic beam, but in this experiment the probe will be polychromatic. This multicolor illumination ptychography offers probe and object characterization for each color, meaning that ptychography identifies the spectral response of the object. In my research I explore multicolor ptychography using a broad bandwidth illumination.


Resilient Dynamic State Estimation In The Presence Of False Information Injection Attacks, Jingyang Lu 2016 Virginia Commonwealth University

Resilient Dynamic State Estimation In The Presence Of False Information Injection Attacks, Jingyang Lu

Theses and Dissertations

The impact of false information injection is investigated for linear dynamic systems with multiple sensors. First, it is assumed that the system is unaware of the existence of false information and the adversary is trying to maximize the negative effect of the false information on Kalman filter's estimation performance under a power constraint. The false information attack under different conditions is mathematically characterized. For the adversary, many closed-form results for the optimal attack strategies that maximize the Kalman filter's estimation error are theoretically derived. It is shown that by choosing the optimal correlation coefficients among the false information ...


Joint Detection-State Estimation And Secure Signal Processing, Mengqi Ren 2016 Virginia Commonwealth University

Joint Detection-State Estimation And Secure Signal Processing, Mengqi Ren

Theses and Dissertations

In this dissertation, joint detection-state estimation and secure signal processing are studied. Detection and state estimation are two important research topics in surveillance systems. The detection problems investigated in this dissertation include object detection and fault detection. The goal of object detection is to determine the presence or absence of an object under measurement uncertainty. The aim of fault detection is to determine whether or not the measurements are provided by faulty sensors. State estimation is to estimate the states of moving objects from measurements with random measurement noise or disturbance, which typically consist of their positions and velocities over ...


Distributed Sparse Signal Recovery In Networked Systems, Puxiao Han 2016 Virginia Commonwealth University

Distributed Sparse Signal Recovery In Networked Systems, Puxiao Han

Theses and Dissertations

In this dissertation, two classes of distributed algorithms are developed for sparse signal recovery in large sensor networks. All the proposed approaches consist of local computation (LC) and global computation (GC) steps carried out by a group of distributed local sensors, and do not require the local sensors to know the global sensing matrix. These algorithms are based on the original approximate message passing (AMP) and iterative hard thresholding (IHT) algorithms in the area of compressed sensing (CS), also known as sparse signal recovery. For distributed AMP (DiAMP), we develop a communication-efficient algorithm GCAMP. Numerical results demonstrate that it outperforms ...


Analysis Of Vocal Fold Kinematics Using High Speed Video, Harikrishnan Unnikrishnan 2016 University of Kentucky

Analysis Of Vocal Fold Kinematics Using High Speed Video, Harikrishnan Unnikrishnan

Theses and Dissertations--Electrical and Computer Engineering

Vocal folds are the twin in-folding of the mucous membrane stretched horizontally across the larynx. They vibrate modulating the constant air flow initiated from the lungs. The pulsating pressure wave blowing through the glottis is thus the source for voiced speech production. Study of vocal fold dynamics during voicing are critical for the treatment of voice pathologies. Since the vocal folds move at 100 - 350 cycles per second, their visual inspection is currently done by strobosocopy which merges information from multiple cycles to present an apparent motion. High Speed Digital Laryngeal Imaging(HSDLI) with a temporal resolution of up to ...


Information-Theoretic Secure Outsourced Computation In Distributed Systems, Zhaohong Wang 2016 University of Kentucky

Information-Theoretic Secure Outsourced Computation In Distributed Systems, Zhaohong Wang

Theses and Dissertations--Electrical and Computer Engineering

Secure multi-party computation (secure MPC) has been established as the de facto paradigm for protecting privacy in distributed computation. One of the earliest secure MPC primitives is the Shamir's secret sharing (SSS) scheme. SSS has many advantages over other popular secure MPC primitives like garbled circuits (GC) -- it provides information-theoretic security guarantee, requires no complex long-integer operations, and often leads to more efficient protocols. Nonetheless, SSS receives less attention in the signal processing community because SSS requires a larger number of honest participants, making it prone to collusion attacks. In this dissertation, I propose an agent-based computing framework using ...


Robust Background Subtraction For Moving Cameras And Their Applications In Ego-Vision Systems, Hasan Sajid 2016 University of Kentucky

Robust Background Subtraction For Moving Cameras And Their Applications In Ego-Vision Systems, Hasan Sajid

Theses and Dissertations--Electrical and Computer Engineering

Background subtraction is the algorithmic process that segments out the region of interest often known as foreground from the background. Extensive literature and numerous algorithms exist in this domain, but most research have focused on videos captured by static cameras. The proliferation of portable platforms equipped with cameras has resulted in a large amount of video data being generated from moving cameras. This motivates the need for foundational algorithms for foreground/background segmentation in videos from moving cameras. In this dissertation, I propose three new types of background subtraction algorithms for moving cameras based on appearance, motion, and a combination ...


Wearable Privacy Protection With Visual Bubble, Shaoqian Wang 2016 University of Kentucky

Wearable Privacy Protection With Visual Bubble, Shaoqian Wang

Theses and Dissertations--Electrical and Computer Engineering

Wearable cameras are increasingly used in many different applications such as entertainment, security, law enforcement and healthcare. In this thesis, we focus on the application of the police worn body camera and behavioral recording using a wearable camera for one-on-one therapy with a child in a classroom or clinic. To protect the privacy of other individuals in the same environment, we introduce a new visual privacy protection technique called visual bubble. Visual bubble is a virtual zone centered around the camera for observation whereas the rest of the environment and people are obfuscated. In contrast to most existing visual privacy ...


Machine Learning Through Mimicry And Association, Nickolas S. Holcomb 2016 Georgia Southern University

Machine Learning Through Mimicry And Association, Nickolas S. Holcomb

University Honors Program Theses

Adaptability is a key missing features that has impeded the growth of assistive robotics. In the traditional model, all actions must be explicitly coded by a skilled programmer familiar with the hardware. This project explores a method of teaching a webcam equipped arm type robot new primitive movement using visual demonstrations.


Blind Front-End Processing Of Dynamic Multi-Channel Wideband Signals, Kevin Jackson 2016 Utah State University

Blind Front-End Processing Of Dynamic Multi-Channel Wideband Signals, Kevin Jackson

All Graduate Theses and Dissertations

In wireless digital communications, the sender and receiver typically know the modulation scheme with which they will be communicating. Automatic modulation identification is the ability to identify the modulation in a communication system with little to no prior knowledge of the modulation scheme. Many techniques for modulation identification operate on many assumptions including that the input signal is base-banded, the carrier frequency is known and that the signal is narrow-band (i.e. neighboring signals in the wide-band are excluded). This work provides the blind processing of an arbitrary wide-band signal to allow such assumptions. The challenges of such a front-end ...


Design, Analysis And Evaluation Of Unmanned Aerial Vehicle Ad Hoc Network For Emergency Response Communications, Robin D. Grodi 2016 Georgia Southern University

Design, Analysis And Evaluation Of Unmanned Aerial Vehicle Ad Hoc Network For Emergency Response Communications, Robin D. Grodi

Electronic Theses & Dissertations

In any emergency situation, it is paramount that communication be established between those affected by an emergency and the emergency responders. This communication is typically initiated by contacting an emergency service number such as 9-1-1 which will then notify the appropriate responders. The communication link relies heavily on the use of the public telephone network. If an emergency situation causes damage to, or otherwise interrupts, the public telephone network then those affected by the emergency are unable to call for help or warn others. A backup emergency response communication system is required to restore communication in areas where the public ...


Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin 2016 Georgia Southern University

Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin

Electronic Theses & Dissertations

Continuous increase in wireless subscriptions and static allocation of wireless frequency bands to the primary users (PUs) are fueling the radio frequency (RF) shortage problem. Cognitive radio network (CRN) is regarded as a solution to this problem as it utilizes the scarce RF in an opportunisticmanner to increase the spectrumefficiency. InCRN, secondary users (SUs) are allowed to access idle frequency bands opportunistically without causing harmful interference to the PUs. In CRN, the SUs determine the presence of PUs through spectrum sensing and access idle bands by means of dynamic spectrum access. Spectrum sensing techniques available in the literature do not ...


Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma 2016 Georgia Southern University

Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma

Electronic Theses & Dissertations

Opportunistic spectrum access in cognitive radio network is proposed for remediation of spectrum under-utilization caused by exclusive licensing for service providers that are intermittently utilizing spectrum at any given geolocation and time. The unlicensed secondary users (SUs) rely on opportunistic spectrum access to maximize spectrum utilization by sensing/identifying the idle bands without causing harmful interference to licensed primary users (PUs). In this thesis, Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks (ROAR) architecture is presented where cloud computing is used for processing and storage of idle channels. Software-defined radios (SDRs) are used as SUs and PUs that identify ...


On The Distance Spectra Of Graphs, Ghodratollah Aalipour, Aida Abiad, Zhanar Berikkyzy, Jay Cummings, Jessica De Silva, Wei Gao, Kristin Heysse, Leslie Hogben, Franklin H.J. Kenter, Jephian C.H. Lin, Michael Tait 2016 Kharazmi University

On The Distance Spectra Of Graphs, Ghodratollah Aalipour, Aida Abiad, Zhanar Berikkyzy, Jay Cummings, Jessica De Silva, Wei Gao, Kristin Heysse, Leslie Hogben, Franklin H.J. Kenter, Jephian C.H. Lin, Michael Tait

Mathematics Publications

The distance matrix of a graph G is the matrix containing the pairwise distances between vertices. The distance eigenvalues of G are the eigenvalues of its distance matrix and they form the distance spectrum of G. We determine the distance spectra of double odd graphs and Doob graphs, completing the determination of distance spectra of distance regular graphs having exactly one positive distance eigenvalue. We characterize strongly regular graphs having more positive than negative distance eigenvalues. We give examples of graphs with few distinct distance eigenvalues but lacking regularity properties. We also determine the determinant and inertia of the distance ...


Development Of Compressive Sensing Techniques For Wideband Spectrum Scanning In Cognitive Radio Networks, Fatima Salahdine, Naima Kaabouch, Hassan El Ghazi 2015 university of north dakota

Development Of Compressive Sensing Techniques For Wideband Spectrum Scanning In Cognitive Radio Networks, Fatima Salahdine, Naima Kaabouch, Hassan El Ghazi

fatima salahdine

Next generation of communication systems will be smart and frequency agile. They will be able to scan the wideband radio spectrum to find the available frequency channel. This process is called compressive sensing. Existing compressive sensing techniques are not accurate and have high processing time, hardware limitations, and computational cost. Thus, this project aims to develop efficient compressive sensing algorithms that deal with uncertainty and enhance the radio spectrum scanning.
 
 


Exploiting Cross Domain Relationships For Target Recognition, Wei Wang 2015 University of Tennessee - Knoxville

Exploiting Cross Domain Relationships For Target Recognition, Wei Wang

Doctoral Dissertations

Cross domain recognition extracts knowledge from one domain to recognize samples from another domain of interest. The key to solving problems under this umbrella is to find out the latent connections between different domains. In this dissertation, three different cross domain recognition problems are studied by exploiting the relationships between different domains explicitly according to the specific real problems.

First, the problem of cross view action recognition is studied. The same action might seem quite different when observed from different viewpoints. Thus, how to use the training samples from a given camera view and perform recognition in another new view ...


Real-Time Digital Effects Processing Using Ios, Jonah W. Clinard 2015 California Polytechnic State University - San Luis Obispo

Real-Time Digital Effects Processing Using Ios, Jonah W. Clinard

Computer Engineering

In today’s society, we are seeing incredible improvements in terms of creating smaller technological devices that behave more and more like the personal computers of yesterday. Mobile “Smart” devices, in particular, are becoming incredibly powerful not just in terms of processing power, but in the fact that they are able to provide assistance to users in their everyday lives. Application developers are now able utilize the power and size of these devices, to create and realize ideas that would have been previously viewed as impossible. This project applies the fields of digital signal processing, music, and mobile application development ...


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