Open Access. Powered by Scholars. Published by Universities.®

Signal Processing Commons

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1 - 30 of 1089

Full-Text Articles in Signal Processing

Gene Regulatory Network Inference From Perturbed Time-Series Expression Data Via Ordered Dynamical Expansion Of Non-Steady State Actors, Mahdi Zamanighomi, Mostafa Zamanian, Michael J. Kimber, Zhengdao Wang Jan 2018

Gene Regulatory Network Inference From Perturbed Time-Series Expression Data Via Ordered Dynamical Expansion Of Non-Steady State Actors, Mahdi Zamanighomi, Mostafa Zamanian, Michael J. Kimber, Zhengdao Wang

Zhengdao Wang

The reconstruction of gene regulatory networks from gene expression data has been the subject of intense research activity. A variety of models and methods have been developed to address different aspects of this important problem. However, these techniques are narrowly focused on particular biological and experimental platforms, and require experimental data that are typically unavailable and difficult to ascertain. The more recent availability of higher-throughput sequencing platforms, combined with more precise modes of genetic perturbation, presents an opportunity to formulate more robust and comprehensive approaches to gene network inference. Here, we propose a step-wise framework for identifying gene-gene regulatory interactions ...


Joint Optimization Of Power Allocation And Training Duration For Uplink Multiuser Mimo Communications, Songtao Lu, Zhengdao Wang Jan 2018

Joint Optimization Of Power Allocation And Training Duration For Uplink Multiuser Mimo Communications, Songtao Lu, Zhengdao Wang

Zhengdao Wang

In this paper, we consider a multiuser multiple-input multiple-output (MU-MIMO) communication system between a base station equipped with multiple antennas and multiple mobile users each equipped with a single antenna. The uplink scenario is considered. The uplink channels are acquired by the base station through a training phase. Two linear processing schemes are considered, namely maximum-ratio combining (MRC) and zero-forcing (ZF). We optimize the training period and optimal training energy under the average and peak power constraint so that an achievable sum rate is maximized.


A Nonconvex Splitting Method For Symmetric Nonnegative Matrix Factorization: Convergence Analysis And Optimality, Songtao Lu, Mingyi Hong, Zhengdao Wang Jan 2018

A Nonconvex Splitting Method For Symmetric Nonnegative Matrix Factorization: Convergence Analysis And Optimality, Songtao Lu, Mingyi Hong, Zhengdao Wang

Zhengdao Wang

Symmetric nonnegative matrix factorization (SymNMF) has important applications in data analytics problems such as document clustering, community detection, and image segmentation. In this paper, we propose a novel nonconvex variable splitting method for solving SymNMF. The proposed algorithm is guaranteed to converge to the set of Karush-Kuhn-Tucker (KKT) points of the nonconvex SymNMF problem. Furthermore, it achieves a global sublinear convergence rate. We also show that the algorithm can be efficiently implemented in parallel. Further, sufficient conditions are provided that guarantee the global and local optimality of the obtained solutions. Extensive numerical results performed on both synthetic and real datasets ...


Many Access For Small Packets Based On Precoding And Sparsity-Aware Recovery, Ronggui Xie, Huarui Yin, Xiaohui Chen, Zhengdao Wang Jan 2018

Many Access For Small Packets Based On Precoding And Sparsity-Aware Recovery, Ronggui Xie, Huarui Yin, Xiaohui Chen, Zhengdao Wang

Zhengdao Wang

Modern mobile terminals produce massive small data packets. For these short-length packets, it is inefficient to follow the current multiple access schemes to allocate transmission resources due to heavy signaling overhead. We propose a non-orthogonal many-access scheme that is well suited for the future communication systems equipped with many receive antennas. The system is modeled as having a block-sparsity pattern with unknown sparsity level (i.e., unknown number of transmitted messages). Block precoding is employed at each single-antenna transmitter to enable the simultaneous transmissions of many users. The number of simultaneously served active users is allowed to be even more ...


Degrees Of Freedom Region Of Wireless X Networks Based On Real Interference Alignment, Mahdi Zamanighomi, Zhengdao Wang Jan 2018

Degrees Of Freedom Region Of Wireless X Networks Based On Real Interference Alignment, Mahdi Zamanighomi, Zhengdao Wang

Zhengdao Wang

We first consider a single hop wireless X network with K transmitters and J receivers, all with a single antenna. Each transmitter conveys an independent message for each receiver. The channel is assumed to have constant coefficients. We develop an interference alignment scheme for this setup and derive an achievable degrees of freedom (DoF) region. We show that in some cases, the derived region meets a previous outer bound, and hence, is the (exact) DoF region. For our achievability schemes, we divide each message into streams and use real interference alignment on the streams. Several previous results on the DoF ...


Retrospective Data Filter, Richard J. Prengaman, Robert E. Thurber, Joe Phipps, Ronald I. Greenberg, Wai L. Hom, James F. Jaworski, Guy W. Riffle Jan 2018

Retrospective Data Filter, Richard J. Prengaman, Robert E. Thurber, Joe Phipps, Ronald I. Greenberg, Wai L. Hom, James F. Jaworski, Guy W. Riffle

Ronald Greenberg

In a target detection communication system, apparatus and method for determining the presence of probable targets based on contacts (which can indicate the presence of a target, noise, chatter, or objects not of interest) detected within a predefined position sector or sectors over a specified number of scans. The position of each detected contact, as a contact of interest, is compared with the positions of contacts detected at previous times or scans. Velocity profiles indicate which previous contacts support the likelihood that the contact of interest represents a target having a velocity within a defined band. The likelihood, which can ...


Dual Method Headphone Amplifier, Timothy P. Murphy, Joseph S. Gross Dec 2017

Dual Method Headphone Amplifier, Timothy P. Murphy, Joseph S. Gross

Electrical Engineering

Many high impedance headphones underperform their full potential when directly connected to the audio source. Amplifiers boost the audio signal and provide the headphones with sufficient power to ensure their maximum performance. The invention of transistors caused vacuum tube implementation to decline, leaving many audiophiles unsatisfied with the transistor’s sound signature. Vacuum tubes and transistors both amplify signals, however the distinct “tube sound” has vanished.

We have designed and created a product where the user selectively switches between solid-state transistor and tube amplification to compare the sound signatures of each amplification method. The ability to switch between the solid-state ...


Realtime Implementation Of An Internal-Model-Principle Signal Identifier, Edris Saleh Mohsen Nov 2017

Realtime Implementation Of An Internal-Model-Principle Signal Identifier, Edris Saleh Mohsen

Electronic Thesis and Dissertation Repository

This thesis presents a new means approach of tuning an adaptive internal model principle based signal identification algorithm whose computational costs are low enough to allow a realtime implementation. The algorithm allows an instantaneous Fourier decomposition of nonstationary signals that have a strongly predictable component. The algorithm is implemented as a feedback loop resulting in a closed loop system with a frequency response of a bandpass filter with notches at the frequencies of the Fourier decomposition. This is achieved through real time selection of the coefficients of the transfer functions in the feedback loop. Previous work showed how the dynamics ...


Feasibility Of 802.11a-Based Transceivers For Vhf/Uhf Communications In Remote Regions, Abhimanyu Nath Oct 2017

Feasibility Of 802.11a-Based Transceivers For Vhf/Uhf Communications In Remote Regions, Abhimanyu Nath

Graduate Theses & Non-Theses

The project focuses on adapting a traditional IEEE802.11a specification originally designed for indoors, to work across mountainous terrains such as areas of rural Montana in the UHF band. The goal of the project is to experiment with various CSMA/CA timing parameters to accommodate long propagation delays between mountain peaks. The simulation tool was built in C++. When links with various data rates and hidden nodes were introduced during worst case performance analysis, severe packet drops and queue latencies were found in the network statistics. A few timing optimizations were explored and alternatives were considered in the systems design ...


Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic Sep 2017

Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

A proposed novel DC-Link VSCF AC-DC-AC electrical power system converter for Embraer 190/195 transport category airplane is presented. The proposed converter could replace the existing conventional system based on the CSCF IDGs. Several contemporary production airplanes already have VSCF as a major or backup source of electrical power. Problems existed with the older VSCF systems in the past; however, the switched power electronics and digital controllers have matured and can be now, in our opinion, safely integrated and replace existing constant-speed hydraulic transmissions powering CSCF AC generators. IGBT power transistors for medium-level power conversion and relatively fast efficient switching ...


On Dual-Band Amplifications Using Dual Two-Tones: Clarifications And Discussion, Siyuan Yan, Xianzhen Yang, Xiao Li, Fu Li Sep 2017

On Dual-Band Amplifications Using Dual Two-Tones: Clarifications And Discussion, Siyuan Yan, Xianzhen Yang, Xiao Li, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

A significant development of recent research in nonlinear distortion is the expansion of the conventional two-tone test for power amplifiers to the concurrent dual-band transmitters, by Amin et al. A general framework using dual two-tones is developed, which shows that the output signal is affected not only by intermodulation (IM) products but also by cross-modulation (CM) products. In this paper, we will make a number of clarifications to Amin et al.'s paper. The effects of IM and CM in passband will be discussed, IM represents a reduction for compressive devices, and CM reflects an interference caused by the signal ...


Design And Validation Of A Low Cost High Speed Atomic Force Microscope, Michael Ganzer, Tien Pham Sep 2017

Design And Validation Of A Low Cost High Speed Atomic Force Microscope, Michael Ganzer, Tien Pham

Journal of Undergraduate Research at Minnesota State University, Mankato

The Atomic Force Microscope (AFM) is an important instrument in nanoscale topography, but it is expensive and slow. The authors designed an AFM to overcome both limitations. To do this, they used an Optical Pickup Unit (OPU) from a DVD player as the laser and photodetector system to minimize cost and they did not implement a vertical control loop, which maximized potential speed. Students will be able to be use this device to make nanoscale measurements and engage in micro-engineering. To prototype this idea, the authors tested an OPU with a silicon wafer and demonstrated the ability to consistently distinguish ...


Separation Of Vocal And Non-Vocal Components From Audio Clip Using Correlated Repeated Mask (Crm), Mohan Kumar Kanuri Aug 2017

Separation Of Vocal And Non-Vocal Components From Audio Clip Using Correlated Repeated Mask (Crm), Mohan Kumar Kanuri

University of New Orleans Theses and Dissertations

Extraction of singing voice from music is one of the ongoing research topics in the field of speech recognition and audio analysis. In particular, this topic finds many applications in the music field, such as in determining music structure, lyrics recognition, and singer recognition. Although many studies have been conducted for the separation of voice from the background, there has been less study on singing voice in particular.

In this study, efforts were made to design a new methodology to improve the separation of vocal and non-vocal components in audio clips using REPET [14]. In the newly designed method, we ...


Distributed Emitter Detector Design Under Imperfect Communication Channel, Soumyadip Patra Aug 2017

Distributed Emitter Detector Design Under Imperfect Communication Channel, Soumyadip Patra

University of New Orleans Theses and Dissertations

We consider the distributed detection of an emitter using multiple sensors deployed at deterministic locations. The signal from the emitter follows a signal attenuation model dependent on the distance between the sensor and the emitter. The sensors transmit their decisions to the fusion center through a parallel access Binary Symmetric Channel (BSC) with a cross-over probability. We seek to optimize the detection performance under a prescribed false alarm at the sensor level and at the system level. We consider the triangular topology structure and using the least favorable emitter range study the impact of the BSC on the system level ...


Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu Aug 2017

Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) are useful tools to analyze brain activities given active stimulation. However, the electromagnetic noise from the MRI distorts the brain signal recording and damages the subject with excessive heat generated on the electrodes attached to the skin. MRI-compatible recording and stimulation systems previously developed at LIBI lab were capable of removing the electromagnetic noise during the imaging process. Previously, the hardware systems had required the integrative software that could control both circuits simultaneously and enable users to easily change recording and stimulation parameters. Graphical user interface (GUI) programmed with computer language informed ...


Feasibility Of Melville Marginalia Authorship Differentiation, Aaron Burdin Aug 2017

Feasibility Of Melville Marginalia Authorship Differentiation, Aaron Burdin

Boise State University Theses and Dissertations

We examine the feasibility of using image processing techniques to determine differentiation in authorship of historical pencil marks. Pencil marks with unattributed and attributed authorship are segmented from digital images of historical books. Analysis is performed on five features that are extracted from the "vertical" pencil marks, with those features used as a basis for authorship of marks. These marks consist of single stroke marks that are interspersed in the same document. We describe the challenges of the digital format that we were given and the steps taken in using autonomous segmentation to save pixel locations of marks. Five mark ...


Wide-Area Measurement-Driven Approaches For Power System Modeling And Analytics, Hesen Liu Aug 2017

Wide-Area Measurement-Driven Approaches For Power System Modeling And Analytics, Hesen Liu

Doctoral Dissertations

This dissertation presents wide-area measurement-driven approaches for power system modeling and analytics. Accurate power system dynamic models are the very basis of power system analysis, control, and operation. Meanwhile, phasor measurement data provide first-hand knowledge of power system dynamic behaviors. The idea of building out innovative applications with synchrophasor data is promising.

Taking advantage of the real-time wide-area measurements, one of phasor measurements’ novel applications is to develop a synchrophasor-based auto-regressive with exogenous inputs (ARX) model that can be updated online to estimate or predict system dynamic responses.

Furthermore, since auto-regressive models are in a big family, the ARX model ...


Two Senior Projects: 2.4 Ghz, 40% Efficiency Radio Frequency Amplifier, Ieee Design Contest, & Design And Implementation Of A Software Costas Loop For Audio Frequencies, Robert J. Tong Aug 2017

Two Senior Projects: 2.4 Ghz, 40% Efficiency Radio Frequency Amplifier, Ieee Design Contest, & Design And Implementation Of A Software Costas Loop For Audio Frequencies, Robert J. Tong

Electrical Engineering

How to Read this Document:

This document combines two senior project reports. The first senior project documents designing a class AB RF amplifier. The second, discusses the design and implementation of a software Costas loop for audio frequencies. The first report begins on the next page, while the Costas loop report starts on page 24. The two reports are orthogonal from one another. It is not a prerequisite to read the RF amplifier report before reading the Costas loop report. This document is merely two reports combined into one document. The second report, about the Costas loop, was written as ...


Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans Jul 2017

Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

In this thesis, we present a new architecture for application-aware cognitive multihop wireless networks (AC-MWN) with testbed implementations and experiments. Cognitive radio is a technique to adaptively use the spectrum so that the resource can be used more efficiently in a low cost way. Multihop wireless networks can be deployed quickly and flexibly without a fixed infrastructure. In presented new architecture, we study backbone routing schemes with network cognition, routing scheme with network coding and spectrum adaptation. A testbed is implemented to test the schemes for AC-MWN. In addition to basic measurements, we implement a video streaming application based on ...


Projected Nesterov’S Proximal-Gradient Algorithm For Sparse Signal Recovery, Renliang Gu, Aleksandar Dogandžić Jul 2017

Projected Nesterov’S Proximal-Gradient Algorithm For Sparse Signal Recovery, Renliang Gu, Aleksandar Dogandžić

Electrical and Computer Engineering Publications

Abstract: We develop a projected Nesterov's proximal-gradient (PNPG) approach for sparse signal reconstruction that combines adaptive step size with Nesterov's momentum acceleration. The objective function that we wish to minimize is the sum of a convex differentiable data-fidelity (negative log-likelihood (NLL)) term and a convex regularization term. We apply sparse signal regularization where the signal belongs to a closed convex set within the closure of the domain of the NLL; the convex-set constraint facilitates flexible NLL domains and accurate signal recovery. Signal sparsity is imposed using the ℓ1 -norm penalty on the signal's linear transform coefficients ...


Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin Jun 2017

Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin

Zhengdao Wang

We consider a single-hop interference network with K transmitters and J receivers, all having M antennas. Each transmitter emits an independent message and each receiver requests an arbitrary subset of the messages. This generalizes the well-known K -user M-antenna interference channel, where each message is requested by a unique receiver. For our setup, we derive the degrees of freedom (DoF) region. The achievability scheme generalizes the interference alignment schemes proposed by Cadambe and Jafar. In particular, we achieve general points in the DoF region by using multiple base vectors and aligning all interferers at a given receiver to the ...


Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin Jun 2017

Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin

Zhengdao Wang

We consider a single hop interference network with K transmitters, each with an independent message and J receivers, all having the same number (M) of antennas. Each receiver requests an arbitrary subset of the messages. This generalizes the well-known K user M antenna interference channel, where each message is requested by a unique receiver. For this setup, we derive the exact degrees of freedom (DoF) region. Our achievability scheme generalizes the interference alignment scheme proposed by Cadambe and Jafar '08. In particular, we achieve general points in the DoF region by using multiple base vectors and aligning the interference at ...


Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben Jun 2017

Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben

Namrata Vaswani

This paper studies the recursive robust principal components analysis problem. If the outlier is the signal-of-interest, this problem can be interpreted as one of recursively recovering a time sequence of sparse vectors, St, in the presence of large but structured noise, Lt. The structure that we assume on Lt is that Lt is dense and lies in a low-dimensional subspace that is either fixed or changes slowly enough. A key application where this problem occurs is in video surveillance where the goal is to separate a slowly changing background (Lt) from moving foreground objects (St) on-the-fly. To solve the above ...


Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben Jun 2017

Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben

Namrata Vaswani

This paper studies the recursive robust principal components analysis problem. If the outlier is the signal-of-interest, this problem can be interpreted as one of recursively recovering a time sequence of sparse vectors, St, in the presence of large but structured noise, Lt. The structure that we assume on Lt is that Lt is dense and lies in a low-dimensional subspace that is either fixed or changes slowly enough. A key application where this problem occurs is in video surveillance where the goal is to separate a slowly changing background (Lt) from moving foreground objects (St) on-the-fly. To solve the above ...


A Nonconvex Splitting Method For Symmetric Nonnegative Matrix Factorization: Convergence Analysis And Optimality, Songtao Lu, Mingyi Hong, Zhengdao Wang Jun 2017

A Nonconvex Splitting Method For Symmetric Nonnegative Matrix Factorization: Convergence Analysis And Optimality, Songtao Lu, Mingyi Hong, Zhengdao Wang

Electrical and Computer Engineering Publications

Symmetric nonnegative matrix factorization (SymNMF) has important applications in data analytics problems such as document clustering, community detection, and image segmentation. In this paper, we propose a novel nonconvex variable splitting method for solving SymNMF. The proposed algorithm is guaranteed to converge to the set of Karush-Kuhn-Tucker (KKT) points of the nonconvex SymNMF problem. Furthermore, it achieves a global sublinear convergence rate. We also show that the algorithm can be efficiently implemented in parallel. Further, sufficient conditions are provided that guarantee the global and local optimality of the obtained solutions. Extensive numerical results performed on both synthetic and real datasets ...


Application Of Optimization Methods To Crack Profile Inversion Using Eddy Currents, John R. Bowler, Wei Zhang, Aleksandar Dogandžić Jun 2017

Application Of Optimization Methods To Crack Profile Inversion Using Eddy Currents, John R. Bowler, Wei Zhang, Aleksandar Dogandžić

John R. Bowler

A numerical scheme for finding crack shapes from eddy current measurements has been developed based on a startdard iterative inversion approach in which a nonlinear least squares objective function quantifying the overall difference between predictions and measurements is minimized. In this paper, steepest descent and conjugate‐gradient methods for minimizing the objective function are investigated and compared. Cramér‐Rao lower bounds on the crack parameters are derived to quantify the accuracy of the estimated crack shape. Cramér‐Rao bounds are also used to indicate improvements in the design of eddy‐current nondestructive evaluation systems.


Predictive Shutdown Systems For Nuclear Power Plants, Drew J. Rankin Jun 2017

Smart Sensing Skin For Detection And Localization Of Fatigue Cracks, Sari Kharroub, Simon Laflamme, Chunhui Song, Daji Qiao, Brent M. Phares, Jian Li Jun 2017

Smart Sensing Skin For Detection And Localization Of Fatigue Cracks, Sari Kharroub, Simon Laflamme, Chunhui Song, Daji Qiao, Brent M. Phares, Jian Li

Daji Qiao

Fatigue cracks on steel components may have strong consequences on the structure's serviceability and strength. Their detection and localization is a difficult task. Existing technologies enabling structural health monitoring have a complex link signal-to-damage or have economic barriers impeding large-scale deployment. A solution is to develop sensing methods that are inexpensive, scalable, with signals that can directly relate to damage. The authors have recently proposed a smart sensing skin for structural health monitoring applications to mesosystems. The sensor is a thin film soft elastomeric capacitor (SEC) that transduces strain into a measurable change in capacitance. Arranged in a network ...


Verification Of Receiver Equalization By Integrating Dataflow Simulation And Physical Channels, David M. Ritter, Tina Smilkstein Dr. Jun 2017

Verification Of Receiver Equalization By Integrating Dataflow Simulation And Physical Channels, David M. Ritter, Tina Smilkstein Dr.

Master's Theses and Project Reports

This thesis combines Keysight’s SystemVue software with a Vector Signal Analyzer (VSA) and Vector Signal Generator (VSG) to test receiver equalization schemes over physical channels. The testing setup, “Equalization Verification,” is intended to be able to evaluate any equalization scheme over any physical channel, and a decision-directed feed-forward LMS equalizer is used as an example. The decision-directed feed-forward LMS equalizer is shown to decrease the BER from 10-2 to 10-3 (average of all trials) over a CAT7 and CAT6A cable, both simulated and physical, for 1GHz and 2GHz carrier, and 80MHz data rate. A wireless channel, 2 ...


Music Synthesizer Senior Project: Danalog, Vikrant A. Marathe Jun 2017

Music Synthesizer Senior Project: Danalog, Vikrant A. Marathe

Electrical Engineering

The Danalog is a 25 key portable digital music synthesizer that uses multiple synthesis methods and effects to generate sounds. Sound varieties included three synthesis methods including FM, subtractive, and sample-based, with up to eight adjustable parameters, at least four effects, including reverb, chorus, and flange, with five adjustable parameters, and at least two note polyphony, and a five band equalizer. The user would be able to adjust these effects using digital encoders and potentiometers and view the settings on two LCD screens. The finals project was unable to meet the original design requirements. The FM synthesis method was primarily ...