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Articles 91 - 120 of 364
Full-Text Articles in Electrical and Computer Engineering
Tree Canopy Analysis: Improving Forest And Tree Health Through Aerial Spectral Measurement, Yaw Amoatin, Adam Hrycyk, Alex Yoon
Tree Canopy Analysis: Improving Forest And Tree Health Through Aerial Spectral Measurement, Yaw Amoatin, Adam Hrycyk, Alex Yoon
Capstone Design Expo Posters
Richmond has a large quantity of trees which currently cannot be efficiently monitored for individual tree health. This lack of monitoring results in high mortality rates. It is to the benefit of the city financially that these trees are saved instead of having to be replaced. The solution includes the delivery of an Unmanned Aerial System (UAS) with modified camera technology for image processing and log identification utilizing Normalized Difference Vegetation Index (NDVI) values as numerical indicators of health. A low-cost, Federal Aviation Administration (FAA) compliant system was required for solution implementation and budget appropriations. It was decided aerial imagery …
Enhancing Fire Fighter Situational Awareness With Remote Uav Thermal Imaging, Jarett Chaine, Nathan Ellingson, Herve Iradukunda
Enhancing Fire Fighter Situational Awareness With Remote Uav Thermal Imaging, Jarett Chaine, Nathan Ellingson, Herve Iradukunda
Capstone Design Expo Posters
Fighting highly dynamic and unpredictable structure fires can be very challenging and dangerous for firefighters. They need full situational awareness of the fire as it evolves. In these situations, it is difficult for firefighters to gain insight on whether they are winning or losing the battle against the fire. By gathering thermal images of a burning structure, our Thermal Imaging System will be able to provide real time data to help first responders mitigate risks associated with unpredictable fire dynamics.
The FAA is currently modifying and creating more regulations to address integrating UAVs with the existing aviation network. This makes …
Dynamic Cg Display For Recovery Cranes, Tariq Haddad, Steven Lemasters
Dynamic Cg Display For Recovery Cranes, Tariq Haddad, Steven Lemasters
Capstone Design Expo Posters
The objective of this project is to give recovery crane operators the ability to visualize the crane's center of gravity, while picking up a load. With this ability, the operators will know when the crane is close to tipping over. Currently, no system dynamically calculates the center of gravity. This is especially important for recovery cranes, which typically work on un-level ground. This system can save a recovery crane company millions in damage to the crane, and prevent injuries to the operator or support personnel on site. Also by storing the data it can help in determining fault if a …
Electric Power Quality Monitoring And Control Of The Soe Clean Room, Bart Thompson, Gabriel Knight, Aubrey Buckner
Electric Power Quality Monitoring And Control Of The Soe Clean Room, Bart Thompson, Gabriel Knight, Aubrey Buckner
Capstone Design Expo Posters
The senior design team was presented with a challenge of addressing power quality issues in the School of Engineering’s clean room. Discussion with the faculty involved in the operation of the room indicated that some power quality issues such as periodic outages and brownouts posed serious potential damage to computer equipment, and solving these issues would save the university money and lost time. The senior design team used Eagle Power Quality Meters to monitor and record voltage waveforms on multiple 120V AC phases for three months and also collected real-time data of current and consumed power from the room. Based …
Development Of A Multi-Objective Evolutionary Algorithm For Strain-Enhanced Quantum Cascade Lasers, Gregory Edward Triplett, David Mueller
Development Of A Multi-Objective Evolutionary Algorithm For Strain-Enhanced Quantum Cascade Lasers, Gregory Edward Triplett, David Mueller
Electrical and Computer Engineering Publications
An automated design approach using an evolutionary algorithm for the development of quantum cascade lasers (QCLs) is presented. Our algorithmic approach merges computational intelligence techniques with the physics of device structures, representing a design methodology that reduces experimental effort and costs. The algorithm was developed to produce QCLs with a three-well, diagonal-transition active region and a five-well injector region. Specifically, we applied this technique to AlxGa1xAs/InyGa1yAs strained active region designs. The algorithmic approach is a non-dominated sorting method using four aggregate objectives: target wavelength, population inversion via longitudinal-optical (LO) phonon extraction, injector level coupling, and an optical gain metric. Analysis …
Intra- And Inter-Fractional Variation Prediction Of Lung Tumors Using Fuzzy Deep Learning, Seonyeong Park, Suk Jin Lee, Elisabeth Weiss, Yuichi Motai
Intra- And Inter-Fractional Variation Prediction Of Lung Tumors Using Fuzzy Deep Learning, Seonyeong Park, Suk Jin Lee, Elisabeth Weiss, Yuichi Motai
Electrical and Computer Engineering Publications
Tumor movements should be accurately predicted to improve delivery accuracy and reduce unnecessary radiation exposure to healthy tissue during radiotherapy. The tumor movements pertaining to respiration are divided into intra-fractional variation occurring in a single treatment session and inter- fractional variation arising between different sessions. Most studies of patients' respiration movements deal with intra-fractional variation. Previous studies on inter-fractional variation are hardly mathematized and cannot predict movements well due to inconstant variation. Moreover, the computation time of the prediction should be reduced. To overcome these limitations, we propose a new predictor for intra- and inter-fractional data variation, called intra- and …
People Counting In Open Spaces, Nick Reuter, Taylor Roberts, Chris Thomas
People Counting In Open Spaces, Nick Reuter, Taylor Roberts, Chris Thomas
Capstone Design Expo Posters
The need addressed in this project is to accurately keep track of individuals in Richmond parks, and provide real-time actionable data for analysis and response. To do this, Satellite systems take pictures, perform object detection and send data to the Central Controller. Central Controller performs accuracy analysis and records end result. It also sends client commands to the satellite systems. Remote client gathers data from the central controller, and allows the user to change satellite system’s operation modes.
There were several constraints associated with the project 1) Supplied Power 2) Privacy protection 3) Number of satellite units (cost) 4) People …
Automatic Sorting Machine Using A Programmable Logic Controller, Tim Parker, Justin Webber, Josh Kirkham
Automatic Sorting Machine Using A Programmable Logic Controller, Tim Parker, Justin Webber, Josh Kirkham
Capstone Design Expo Posters
This project is designed to demonstrate the uses of programmable logic controllers (PLC’s). The end result of this project will be used to generate interest in VCU’s Industrial Controls classes with prospective students as well as employers. The project involves building a working demonstration showing how PLC’s are used to control manufacturing systems. This system will be mobile and able to be used in different locations including the PLC lab, where students in the Industrial Controls class can also use it to test their knowledge of PLC programming. The system consists of a conveyor belt and sensors that sorts different …
Human Occupancy: A Non-Invasive Solution, Hamid Golgiri, Patrick Van Hoecke, Derrick Williams
Human Occupancy: A Non-Invasive Solution, Hamid Golgiri, Patrick Van Hoecke, Derrick Williams
Capstone Design Expo Posters
Currently, it is difficult to find an available location within a crowded setting. To solve this spatial issue, the team wants to be able to inform people of the density in commonly-occupied areas. To do this, they will need to develop Area Occupancy Device Modules (AODMs) to gather thermal readings. After which, the data will be sent to a central coordinator via mesh network communication. This coordinator will then interpret the data and display its analysis in a graphical user interface (GUI). The system is constrained in that it cannot gather defining characteristics of the people it’s observing. Additionally, the …
Multi-Channel Unbounded Optical Communication Through Modulation Of Led Lighting, Nicolás Andrade, Aaron Jones
Multi-Channel Unbounded Optical Communication Through Modulation Of Led Lighting, Nicolás Andrade, Aaron Jones
Capstone Design Expo Posters
With the ever-increasing demand for more mobile bandwidth and higher data transfer rates, expansion into the Terahertz spectral range is inevitable. Modern Wi-Fi technologies (2.4 GHz and 5 GHz) theoretically support data rates up to only a few Gbps. A newly emerging technology, Light Fidelity (Li-Fi) provides communication with potentially Tbps rates through LED lighting. One unique benefit of Li-Fi is that it can be used simultaneously for illumination and high-speed, secure (line-of-sight) communication. Li-Fi would be best utilized in conjunction with Wi-Fi and mobile LTE networks as it is more suitable for one-way short range communication due to relatively …
Fluid Routing System: Industrial Automation And Simulation, Sean De Arras, Andy Fabian, Shellie Lundquist
Fluid Routing System: Industrial Automation And Simulation, Sean De Arras, Andy Fabian, Shellie Lundquist
Capstone Design Expo Posters
Newport News Shipbuilding (NNS) builds the biggest ships in the world. These ships store and deliver millions of gallons of fluids via computer-controlled networks of pipes, valves, pumps, and tanks. A working, small scale demonstrator of these systems is needed for NNS to use in training and educational demonstrations. The demonstrator needs to allow for functional control of physical parameters by implementing a working instrumentation and control (I&C) system. Core components of this system are a programmable logic controller (PLC), a software development platform, a simulator, and a graphical user interface (GUI) on a human machine interface (HMI).
Project deliverables …
Gnu Radio Companion (Grc) On Software Defined Radio Platforms, Jacob Ramey, James Begemann, Richard Hite
Gnu Radio Companion (Grc) On Software Defined Radio Platforms, Jacob Ramey, James Begemann, Richard Hite
Capstone Design Expo Posters
Software defined radio (SDR) is a method to design radio frequency (RF) signal systems using software to implement radio components that are normally implemented in hardware. Several examples of components that can be designed in SDR include RF signal filters, signal amplifiers, and signal resamplers. SDR applications include amateur radio transmission, aircraft and ship tracking, RF communications, and radio astronomy, to name a few. A great advantage of implementing a RF system in software is that the system developed in software is more flexible and upgradeable than a system designed with hardware alone.
QRC Technologies offers a wide range of …
Kinectvision360: A Real-Time Human Tracking System, Robert Ha, Ravideep Marwaha, Joseph Crouch
Kinectvision360: A Real-Time Human Tracking System, Robert Ha, Ravideep Marwaha, Joseph Crouch
Capstone Design Expo Posters
KinectVision360 project integrates multiple Microsoft Kinect sensors to investigate the capabilities of the low cost human interactive device to apply them to modern problems in comparison to high cost devices. The project includes human face/skeletal tracking and a larger field of vision. We incorporate three Kinects (1st generation) and a custom computer with components necessary to process large amounts of data in real-time. Figure 1 represents an overview of the processes the program follows in order to execute and visualize the data for tracking. The “FaceTracking” class contains algorithms and logic to retrieve skeletal information from infrared depth sensors in …
Uav Wireless Relay, Paul Kirchoff, Lawrence Ng, David Vieth
Uav Wireless Relay, Paul Kirchoff, Lawrence Ng, David Vieth
Capstone Design Expo Posters
Often a scenario arises in which it is necessary to collection information from a hostile environment and the safest way to do this is the deployment of a small unmanned ground vehicle (UGV). In this situation the UGV will move around the environment while sending a live data stream back to the ground base. However, there can be limits on the maneuverability and range of the UGV making it difficult to complete this mission. To solve this problem unmanned aerial vehicles (UAV) are used to assist in both the deployment of the UGV as well as handling the connection between …
Ingan Leds For General Lighting: Overcoming Efficiency Droop At High Current Injection, Nicolas Andrade
Ingan Leds For General Lighting: Overcoming Efficiency Droop At High Current Injection, Nicolas Andrade
AUCTUS: The Journal of Undergraduate Research and Creative Scholarship
According to the Energy Information Administration's Annual Energy Outlook report in 2011, the United States alone consumed 97.8 quadrillion Btus (quads) of primary energy in 2010. Roughly 41% of this energy was consumed for electricity use, with 18% of the electricity being dedicated to lighting. The International Energy Agency (IEA) estimated light consumption of this scale translates to CO2 production equivalent to 70% of the emissions from all of the world's light passenger vehicles. Pollution levels at this rate caused 18,200 premature deaths, 2,100,000 days of medication, and 29 million cases of lower respiratory symptoms.
Ultra–Low Power Straintronic Nanomagnetic Computing With Saw Waves: An Experimental Study Of Saw Induced Magnetization Switching And Properties Of Magnetic Nanostructures, Vimal G. Sampath
Theses and Dissertations
A recent International Technology Roadmap for Semiconductors (ITRS) report (2.0, 2015 edition) has shown that Moore’s law is unlikely to hold beyond 2028. There is a need for alternate devices to replace CMOS based devices, if further miniaturization and high energy efficiency is desired. The goal of this dissertation is to experimentally demonstrate the feasibility of nanomagnetic memory and logic devices that can be clocked with acoustic waves in an extremely energy efficient manner. While clocking nanomagnetic logic by stressing the magnetostrictive layer of a multiferroic logic element with with an electric field applied across the piezoelectric layer is known …
The Dawn Of New Quantum Dots: Synthesis And Characterization Of Ge1-Xsnx Nanocrystals For Tunable Bandgaps., Richard J. Esteves
The Dawn Of New Quantum Dots: Synthesis And Characterization Of Ge1-Xsnx Nanocrystals For Tunable Bandgaps., Richard J. Esteves
Theses and Dissertations
Ge1-xSnx alloys are among a small class of benign semiconductors with composition tunable bandgaps in the near-infrared spectrum. As the amount of Sn is increased the band energy decreases and a transition from indirect to direct band structure occurs. Hence, they are prime candidates for fabrication of Si-compatible electronic and photonic devices, field effect transistors, and novel charge storage device applications. Success has been achieved with the growth of Ge1-xSnx thin film alloys with Sn compositions up to 34%. However, the synthesis of nanocrystalline alloys has proven difficult due to larger discrepancies (~14%) in …
Resilient Dynamic State Estimation In The Presence Of False Information Injection Attacks, Jingyang Lu
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 and allocating …
Distributed Sparse Signal Recovery In Networked Systems, Puxiao Han
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 …
In-Shoe Plantar Pressure System To Investigate Ground Reaction Force Using Android Platform, Ahmed A. Mostfa
In-Shoe Plantar Pressure System To Investigate Ground Reaction Force Using Android Platform, Ahmed A. Mostfa
Theses and Dissertations
Human footwear is not yet designed to optimally relieve pressure on the heel of the foot. Proper foot pressure assessment requires personal training and measurements by specialized machinery. This research aims to investigate and hypothesize about Preferred Transition Speed (PTS) and to classify the gait phase of explicit variances in walking patterns between different subjects. An in-shoe wearable pressure system using Android application was developed to investigate walking patterns and collect data on Activities of Daily Living (ADL). In-shoe circuitry used Flexi-Force A201 sensors placed at three major areas: heel contact, 1st metatarsal, and 5th metatarsal with a PIC16F688 microcontroller …
Beyond Conventional C-Plane Gan-Based Light Emitting Diodes: A Systematic Exploration Of Leds On Semi-Polar Orientations, Morteza Monavarian
Beyond Conventional C-Plane Gan-Based Light Emitting Diodes: A Systematic Exploration Of Leds On Semi-Polar Orientations, Morteza Monavarian
Theses and Dissertations
Despite enormous efforts and investments, the efficiency of InGaN-based green and yellow-green light emitters remains relatively low, and that limits progress in developing full color display, laser diodes, and bright light sources for general lighting. The low efficiency of light emitting devices in the green-to-yellow spectral range, also known as the “Green Gap”, is considered a global concern in the LED industry. The polar c-plane orientation of GaN, which is the mainstay in the LED industry, suffers from polarization-induced separation of electrons and hole wavefunctions (also known as the “quantum confined Stark effect”) and low indium incorporation efficiency that …
Optical Investigations Of Ingan Heterostructures And Gesn Nanocrystals For Photonic And Phononic Applications: Light Emitting Diodes And Phonon Cavities, Shopan D. Hafiz
Optical Investigations Of Ingan Heterostructures And Gesn Nanocrystals For Photonic And Phononic Applications: Light Emitting Diodes And Phonon Cavities, Shopan D. Hafiz
Theses and Dissertations
InGaN heterostructures are at the core of blue light emitting diodes (LEDs) which are the basic building blocks for energy efficient and environment friendly modern white light generating sources. Through quantum confinement and electronic band structure tuning on the opposite end of the spectrum, Ge1−xSnx alloys have recently attracted significant interest due to its potential role as a silicon compatible infra-red (IR) optical material for photodetectors and LEDs owing to transition to direct bandgap with increasing Sn. This thesis is dedicated to establishing an understanding of the optical processes and carrier dynamics in InGaN heterostructures for achieving …
Hybrid Straintronics-Spintronics: Energy-Efficient Non-Volatile Devices For Boolean And Non-Boolean Computation, Ayan K. Biswas
Hybrid Straintronics-Spintronics: Energy-Efficient Non-Volatile Devices For Boolean And Non-Boolean Computation, Ayan K. Biswas
Theses and Dissertations
Research in future generation computing is focused on reducing energy dissipation while maintaining the switching speed in a binary operation to continue the current trend of increasing transistor-density according to Moore’s law. Unlike charge-based CMOS technology, spin-based nanomagnetic technology, based on switching bistable magnetization of single domain shape-anisotropic nanomagnets, has the potential to achieve ultralow energy dissipation due to the fact that no charge motion is directly involved in switching. However, switching of magnetization has not been any less dissipative than switching transistors because most magnet switching schemes involve generating a current to produce a magnetic field, or spin transfer …
Optimizing Virtual Machine I/O Performance In Cloud Environments, Tao Lu
Optimizing Virtual Machine I/O Performance In Cloud Environments, Tao Lu
Theses and Dissertations
Maintaining closeness between data sources and data consumers is crucial for workload I/O performance. In cloud environments, this kind of closeness can be violated by system administrative events and storage architecture barriers. VM migration events are frequent in cloud environments. VM migration changes VM runtime inter-connection or cache contexts, significantly degrading VM I/O performance. Virtualization is the backbone of cloud platforms. I/O virtualization adds additional hops to workload data access path, prolonging I/O latencies. I/O virtualization overheads cap the throughput of high-speed storage devices and imposes high CPU utilizations and energy consumptions to cloud infrastructures. To maintain the closeness between …
Joint Detection-State Estimation And Secure Signal Processing, Mengqi Ren
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 …
Electric Field Controlled Strain Induced Switching Of Magnetization Of Galfenol Nanomagnets In Magneto-Electrically Coupled Multiferroic Stack, Hasnain Ahmad
Theses and Dissertations
The ability to control the bi-stable magnetization states of shape anisotropic single domain nanomagnets has enormous potential for spawning non-volatile and energy-efficient computing and signal processing systems. One of the most energy efficient switching methods is to adopt a system of a 2-phase multiferroic nanomagnet, where a voltage applied on the piezoelectric layer generates a strain in it and the strain is elastically transferred to the magnetostrictive nanomagnet which rotates the magnetization states of the nanomagnet at room temperature via the converse magnet-electric effect. Recently, it has been demonstrated that the magnetization of a Co nanomagnet can be switched between …
Exploration Of Erasure-Coded Storage Systems For High Performance, Reliability, And Inter-Operability, Pradeep Subedi
Exploration Of Erasure-Coded Storage Systems For High Performance, Reliability, And Inter-Operability, Pradeep Subedi
Theses and Dissertations
With the unprecedented growth of data and the use of low commodity drives in local disk-based storage systems and remote cloud-based servers has increased the risk of data loss and an overall increase in the user perceived system latency. To guarantee high reliability, replication has been the most popular choice for decades, because of simplicity in data management. With the high volume of data being generated every day, the storage cost of replication is very high and is no longer a viable approach.
Erasure coding is another approach of adding redundancy in storage systems, which provides high reliability at a …
Autonomous Navigation With Obstacle Avoidance For Unmanned Aircraft Systems Using Milp, James A. Devens
Autonomous Navigation With Obstacle Avoidance For Unmanned Aircraft Systems Using Milp, James A. Devens
Theses and Dissertations
Autonomous coordination among multiple aerial vehicles to ensure a collision free airspace is a critical aspect of today’s airspace. With the rise of Unmanned Aerial Vehicles (UAVs) in the military and commercial sectors, obstacle avoidance in a densely populated airspace is necessary. This thesis investigates finding optimal or near-optimal trajectories in real-time for aircraft in complex airspaces containing a large number of obstacles. The solution for the trajectories is described as a linear program subject to mixed integer constraints, known as a Mixed Integer Linear Program (MILP). The resulting MILP problem is solved in real time using a well-known, public …
Pattern Recognition In Class Imbalanced Datasets, Nahian A. Siddique
Pattern Recognition In Class Imbalanced Datasets, Nahian A. Siddique
Theses and Dissertations
Class imbalanced datasets constitute a significant portion of the machine learning problems of interest, where recognizing the ‘rare class’ is the primary objective for most applications. Traditional linear machine learning algorithms are often not effective in recognizing the rare class. In this research work, a specifically optimized feed-forward artificial neural network (ANN) is proposed and developed to train from moderate to highly imbalanced datasets.
The proposed methodology deals with the difficulty in classification task in multiple stages—by optimizing the training dataset, modifying kernel function to generate the gram matrix and optimizing the NN structure. First, the training dataset is extracted …
Coherent Spin Transport In Nanowire Spin Valves And Novel Spintronic Device Possibilities, Md Iftekhar Hossain
Coherent Spin Transport In Nanowire Spin Valves And Novel Spintronic Device Possibilities, Md Iftekhar Hossain
Theses and Dissertations
Coherent injection, detection and manipulation of spins in semiconductor nansotructures can herald a new genre of information processing devices that are extremely energy-efficient and non-volatile. For them to work reliably, spin coherence must be maintained across the device by suppressing spin relaxation. Suppression can be accomplished by structural engineering, such as by confining spin carriers to the lowest subband in a semiconductor quantum wire. Accordingly, we have fabricated 50-nm diameter InSb nanowire spin valves capped with Co and Ni nanocontacts in which a single conduction subband is occupied by electrons at room temperature. This extreme quantum confinement has led to …