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Electronic Theses and Dissertations

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Full-Text Articles in Computer Engineering

Deep Siamese Neural Networks For Facial Expression Recognition In The Wild, Wassan Hayale Jan 2020

Deep Siamese Neural Networks For Facial Expression Recognition In The Wild, Wassan Hayale

Electronic Theses and Dissertations

The variation of facial images in the wild conditions due to head pose, face illumination, and occlusion can significantly affect the Facial Expression Recognition (FER) performance. Moreover, between subject variation introduced by age, gender, ethnic backgrounds, and identity can also influence the FER performance. This Ph.D. dissertation presents a novel algorithm for end-to-end facial expression recognition, valence and arousal estimation, and visual object matching based on deep Siamese Neural Networks to handle the extreme variation that exists in a facial dataset. In our main Siamese Neural Networks for facial expression recognition, the first network represents the classification framework, where ...


Automated Recognition Of Facial Affect Using Deep Neural Networks, Behzad Hasani Jan 2020

Automated Recognition Of Facial Affect Using Deep Neural Networks, Behzad Hasani

Electronic Theses and Dissertations

Automated Facial Expression Recognition (FER) has been a topic of study in the field of computer vision and machine learning for decades. In spite of efforts made to improve the accuracy of FER systems, existing methods still are not generalizable and accurate enough for use in real-world applications. Many of the traditional methods use hand-crafted (a.k.a. engineered) features for representation of facial images. However, these methods often require rigorous hyper-parameter tuning to achieve favorable results.

Recently, Deep Neural Networks (DNNs) have shown to outperform traditional methods in visual object recognition. DNNs require huge data as well as powerful ...


Microgrid-Enabled Reactive Power Support To Enhance Grid Economics, Sarhan Hasan Jan 2020

Microgrid-Enabled Reactive Power Support To Enhance Grid Economics, Sarhan Hasan

Electronic Theses and Dissertations

Reactive power plays an essential role in voltage control and stability in electric power systems. Various Volt/VAR techniques are utilized in electric power systems to maintain the voltage profile within defined acceptable limits and accordingly provide reliability and stability. Reactive power has been commonly generated through large-scale synchronous generators or distributed capacitor banks to provide proper transmission and distribution level system management, however, reactive power can be further used as an effective means to reduce total system operation cost. In this dissertation, an optimal reactive power model is proposed to determine the optimal nodal reactive powers that result in ...


Xylo-Bot: A Therapeutic Robot-Based Music Platform For Children With Autism, Huanghao Feng Jan 2020

Xylo-Bot: A Therapeutic Robot-Based Music Platform For Children With Autism, Huanghao Feng

Electronic Theses and Dissertations

Children with Autism Spectrum Disorder (ASD) experience deficits in verbal and nonverbal communication skills, including motor control, emotional facial expressions, and eye gaze / joint attention. This Ph.D. dissertation focuses on studying the feasibility and effectiveness of using a social robot, called NAO, and a toy music instrument, xylophone, at modeling and improving the social responses and behaviors of children with ASD. In our investigation, we designed an autonomous social interactive music teaching system to fulfill this mission.

A novel modular robot-music teaching system consisting of three modules is presented. Module 1 provides an autonomous self-awareness positioning system for the ...


A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay Jan 2019

A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay

Electronic Theses and Dissertations

The proliferation of mobile devices in the BRIC countries has prompted them to develop policies to manage the security of these devices. In China, mobile devices are a primary tool for payments. As a result, China instituted in 2017 a cyber security policy that applies to mobile devices giving China broad authority to manage cyber threats. The United States has a similar need for a cyber policy. Mobile devices are likely to become a primary payment tool in the United States soon. DHS has also identified a need for more effective security policy in mobile devices for government operations. This ...


Optimal Design And Planning Of Hybrid Ac/Dc Microgrid, Hossein Lotfi Jan 2019

Optimal Design And Planning Of Hybrid Ac/Dc Microgrid, Hossein Lotfi

Electronic Theses and Dissertations

The traditional approach for microgrid design and deployment has been mainly focused on AC systems. DC microgrids, however, are gaining attention due to numerous advantages they provide over AC microgrids, such as removing the need for synchronization and frequency adjustment as well as appropriateness in supporting DC loads and distributed energy resources (DERs). Moreover, considering that both AC and DC DERs are utilized in microgrids, hybrid microgrids would provide viable and economic solutions as they can potentially eliminate the need for AC-to-DC or DC-to-AC voltage conversions. This dissertation focuses on a hybrid microgrid planning model with the objective of minimizing ...


Application Of Microgrids In Supporting The Utility Grid, Alireza Majzoobi Jan 2019

Application Of Microgrids In Supporting The Utility Grid, Alireza Majzoobi

Electronic Theses and Dissertations

Distributed renewable energy resources have attracted significant attention in recent years due to the falling cost of the renewable energy technology, extensive federal and state incentives, and the application in improving load-point reliability. This growing proliferation, however, is changing the traditional consumption load curves by adding considerable levels of variability and further challenging the electricity supply-demand balance. In this dissertation, the application of microgrids in effectively capturing the distribution network net load variability, caused primarily by the prosumers, is investigated. Microgrids provide a viable and localized solution to this challenge while removing the need for costly investments by the electric ...


3d Formation Control In Multi-Robot Teams Using Artificial Potential Fields, Sanjana Reddy Mohan Jan 2019

3d Formation Control In Multi-Robot Teams Using Artificial Potential Fields, Sanjana Reddy Mohan

Electronic Theses and Dissertations

Multi-robot teams find applications in emergency response, search and rescue operations, convoy support and many more. Teams of autonomous aerial vehicles can also be used to protect a cargo of airplanes by surrounding them in some geometric shape. This research develops a control algorithm to attract UAVs to one or a set of bounded geometric shapes while avoiding collisions, re-configuring in the event of departure or addition of UAVs and maneuvering in mission space while retaining the configuration. Using potential field theory, weighted vector fields are described to attract UAVs to a desired formation. In order to achieve this, three ...


Improvements Of And Extensions To Fsmweb: Testing Mobile Apps, Ahmed Fawzi Al Haddad Jan 2019

Improvements Of And Extensions To Fsmweb: Testing Mobile Apps, Ahmed Fawzi Al Haddad

Electronic Theses and Dissertations

A mobile application is a software program that runs on mobile device. In 2017, 178.1 billion mobile apps downloaded and the number is expected to grow to 258.2 billion app downloads in 2022 [19]. The number of app downloads poses a challenge for mobile application testers to find the right approach to test apps. This dissertation extends the FSMWeb approach for testing web applications [50] to test mobile applications (FSMApp). During the process of analyzing FSMWeb how it could be extended to test Mobile Apps, a number of shortcomings were detected which we improved upon. We discuss these ...


Protection Of High-Voltage Transformer Bushings And Other Brittle Structures Against Impact, Christine Nichole Henderson Jan 2019

Protection Of High-Voltage Transformer Bushings And Other Brittle Structures Against Impact, Christine Nichole Henderson

Electronic Theses and Dissertations

This dissertation contributes unique approaches to improve the fundamental understanding of the impact behavior of porcelain high-voltage (HV) transformer bushings under high-velocity impact, with a focus on their protection with feasible methods which could be quickly applied in service to prevent vandalism and other undesirable impact situations. The bushings are brittle and pressurized; prone to explosive damage when hit by a high-velocity projectile. Damaged bushings can destroy transformers and entire substations in complex fashions. This can put the power grid at risk for cascading failures and electrical blackouts, affecting consumers. Therefore, suggesting practical approaches which could be used to protect ...


Studying Facial Expression Recognition And Imitation Ability Of Children With Autism Spectrum Disorder In Interaction With A Social Robot, Farzaneh Askari Jan 2018

Studying Facial Expression Recognition And Imitation Ability Of Children With Autism Spectrum Disorder In Interaction With A Social Robot, Farzaneh Askari

Electronic Theses and Dissertations

Children with Autism Spectrum Disorder (ASD) experience limited abilities in recognizing non-verbal elements of social interactions such as facial expressions [1]. They also show deficiencies in imitating facial expressions in social situations. In this Master thesis, we focus on studying the ability of children with ASD in recognizing facial expressions and imitating the expressions using a rear-projected expressive humanoid robot, called Ryan. Recent studies show that social robots such as Ryan have great potential for autism therapy. We designed and developed three studies, first to evaluate the ability of children with ASD in recognizing facial expressions that are presented to ...


Development Of A Locomotion And Balancing Strategy For Humanoid Robots, Emile Bahdi Jan 2018

Development Of A Locomotion And Balancing Strategy For Humanoid Robots, Emile Bahdi

Electronic Theses and Dissertations

The locomotion ability and high mobility are the most distinguished features of humanoid robots. Due to the non-linear dynamics of walking, developing and controlling the locomotion of humanoid robots is a challenging task. In this thesis, we study and develop a walking engine for the humanoid robot, NAO, which is the official robotic platform used in the RoboCup Spl. Aldebaran Robotics, the manufacturing company of NAO provides a walking module that has disadvantages, such as being a black box that does not provide control of the gait as well as the robot walk with a bent knee. The latter disadvantage ...


Force-Canceling Mixer Algorithm For Vehicles With Fully-Articulated Radially Symmetric Thruster Arrays, Joseph Nicholas Casabona Jan 2018

Force-Canceling Mixer Algorithm For Vehicles With Fully-Articulated Radially Symmetric Thruster Arrays, Joseph Nicholas Casabona

Electronic Theses and Dissertations

A new type of fully-holonomic aerial vehicle is identified and developed that can optionally utilize automatic cancellation of excessive thruster forces to maintain precise control despite little or no throttle authority. After defining the physical attributes of the new vehicle, a flight control mixer algorithm is defined and presented. This mixer is an input/output abstraction that grants a flight control system (or pilot) full authority of the vehicle's position and orientation by means of an input translation vector and input torque vector. The mixer is shown to be general with respect to the number of thrusters in the ...


Developing An Affect-Aware Rear-Projected Robotic Agent, Ali Mollahosseini Jan 2018

Developing An Affect-Aware Rear-Projected Robotic Agent, Ali Mollahosseini

Electronic Theses and Dissertations

Social (or Sociable) robots are designed to interact with people in a natural and interpersonal manner. They are becoming an integrated part of our daily lives and have achieved positive outcomes in several applications such as education, health care, quality of life, entertainment, etc. Despite significant progress towards the development of realistic social robotic agents, a number of problems remain to be solved. First, current social robots either lack enough ability to have deep social interaction with human, or they are very expensive to build and maintain. Second, current social robots have yet to reach the full emotional and social ...


Abstraction Hierarchies For Multi-Agent Pathfinding, Aaron R. Kraft Jan 2017

Abstraction Hierarchies For Multi-Agent Pathfinding, Aaron R. Kraft

Electronic Theses and Dissertations

Multi-Agent Pathfinding is an NP-Complete search problem with a branching factor that is exponential in the number of agents. Because of this exponential feature, it can be difficult to solve optimally using traditional search techniques, even for relatively small problems. Many recent optimal solvers have attempted to reduce the complexity of the problem by resolving the conflicts between agent paths separately. Very little of this research has focused on creating quality heuristics to help solve the problem. In this thesis, we create heuristics using sub-problems created by removing agents from a complete problem instance. We combine this with the Independence ...


Explaining The Performance Of Bidirectional Dijkstra And A* On Road Networks, Sneha Sawlani Jan 2017

Explaining The Performance Of Bidirectional Dijkstra And A* On Road Networks, Sneha Sawlani

Electronic Theses and Dissertations

The heuristic search community traditionally uses A* as the baseline algorithm for their research methods. Research papers in the road networks community, however, often build upon Dijkstra's algorithm and use Bidirectional Dijkstra's algorithm as their baseline. This thesis investigates the performance of A* and Bidirectional Dijkstra in road networks to see how they compare and to see if there is a principled explanation for the different approaches. Our analysis reveals why Bidirectional Dijkstra can perform well in this domain, but also shows a simple mistake that can be made when building test problems that hurts the performance of ...


Optimized Trajectory Generation For Car-Like Robots On A Closed Loop Track, Tyler Friedl Jan 2017

Optimized Trajectory Generation For Car-Like Robots On A Closed Loop Track, Tyler Friedl

Electronic Theses and Dissertations

This thesis presents a method for generating an optimized path through a given track. The path is generated by choosing waypoints throughout the track then iteratively optimizing the position of these waypoints. The waypoints are then connected by optimized paths represented by curvature polynomials. The end result is a path through the track represented as a spline of curvature polynomials. This method is applied to multiple simulated tracks and the results are presented. By generating and representing the paths in the continuous domain, the method has improved computational efficiency from many of the discrete methods used to generate an optimal ...


System Identification Of A Circulation Control Unmanned Aerial Vehicle, Mohammed Agha Jan 2017

System Identification Of A Circulation Control Unmanned Aerial Vehicle, Mohammed Agha

Electronic Theses and Dissertations

The advancement in automation and sensory systems in recent years has led to an increase the demand of UAV missions. Due to this increase in demand, the research community has gained interest in investigating UAV performance enhancing systems. Circulation Control (CC), which is an active control flow method used to enhance UAV lift, is a performance enhancing system currently studied. In prior research, experimental studies have shown that Circulation Control wings (CCW) implemented on class-I UAVs can reduce take-off distance by 54%. Wind tunnel tests reveal that CC improves aircraft payload capabilities through lift enhancement. Increasing aircraft payload capabilities causes ...


Design And Development Of The Ebear: A Socially Assistive Robot For Elderly People With Depression, Amirhossein Kargarbideh Jan 2016

Design And Development Of The Ebear: A Socially Assistive Robot For Elderly People With Depression, Amirhossein Kargarbideh

Electronic Theses and Dissertations

There has been tremendous progress in the field of robotics in the past decade and especially developing humanoid robots with social abilities that can assist human at a socio-emotional level. The objective of this thesis is to develop and study a perceptive and expressive animal-like robot equipped with artificial intelligence in assisting the elderly people with depression. We investigated how social robots can become companions of elderly individuals with depression and improve their mood and increase their happiness and well-being. The robotic platform built in this thesis is a bear-like robot called the eBear. The eBear can show facial expression ...


On The Viability Of Quantitative Assessment Methods In Software Engineering And Software Services, Joseph D. Lucente Jun 2015

On The Viability Of Quantitative Assessment Methods In Software Engineering And Software Services, Joseph D. Lucente

Electronic Theses and Dissertations

IT help desk operations are expensive. Costs associated with IT operations present challenges to profit goals. Help desk managers need a way to plan staffing levels so that labor costs are minimized while problems are resolved efficiently. An incident prediction method is needed for planning staffing levels. The potential value of a solution to this problem is important to an IT service provider since software failures are inevitable and their timing is difficult to predict. In this research, a cost model for help desk operations is developed. The cost model relates predicted incidents to labor costs using real help desk ...


Alternative Models Of Connectivity: Reclaiming Networked Spaces, Philip M. Bain Jun 2015

Alternative Models Of Connectivity: Reclaiming Networked Spaces, Philip M. Bain

Electronic Theses and Dissertations

Alternative networking is a growing field of study and practice due to advancements in computer networking hardware, and software protocols. Methods of integrating alternative networking configurations into infrastructure present enhanced forms of empowerment and embodiment for participants. Through an analysis of multiple hardware and software examples, this research suggests that practices of sharing and collaboration, which are embedded in the history of computer networking, have the potential to reinvigorate the notion of a virtual public sphere, and support the ideals of digital democracy.


Fail-Safe Test Generation Of Safety Critical Systems, Salwa Elakeili Mar 2015

Fail-Safe Test Generation Of Safety Critical Systems, Salwa Elakeili

Electronic Theses and Dissertations

This dissertation introduces a technique for testing proper failure mitigation in safety critical systems. Unlike other approaches which integrate behavioral and failure models, and then generate tests from the integrated model, we build safety mitigation tests from an existing behavioral test suite, using an explicit mitigation model for which we generate mitigation paths which are then woven at selected failure points into the original test suite to create failure-mitigation tests (safety mitigation test).


Towards Closed-Loop Deep Brain Stimulation: Behavior Recognition From Human Stn, Soroush Niketeghad Jan 2015

Towards Closed-Loop Deep Brain Stimulation: Behavior Recognition From Human Stn, Soroush Niketeghad

Electronic Theses and Dissertations

Deep brain stimulation (DBS) provides significant therapeutic benefit for movement disorders such as Parkinson’s disease (PD). Current DBS devices lack real-time feedback (thus are open loop) and stimulation parameters are adjusted during scheduled visits with a clinician. A closed-loop DBS system may reduce power consumption and side effects by adjusting stimulation parameters based on patient’s behavior. Thus behavior detection is a major step in designing such systems. Various physiological signals can be used to recognize the behaviors. Subthalamic Nucleus (STN) Local field Potential (LFP) is a great candidate signal for the neural feedback, because it can be recorded ...


Secure Map Generation For Multiplayer, Turn-Based Strategy Games, Stephen L. Rice Jan 2014

Secure Map Generation For Multiplayer, Turn-Based Strategy Games, Stephen L. Rice

Electronic Theses and Dissertations

In strategy games, players compete against each other on randomly generated maps in an attempt to prove their superior skill. Traditionally, these games rely on a client/server architecture with one player fulfilling the role of server and holding responsibility for the map generation process. We propose, analyze and evaluate a method that allows these maps to be created in a peer-to-peer fashion and thus reduce the potential for cheating. We provide an example map generation program that puts these concepts into action and demonstrate how it can be extended and customized for any game. Finally, we analyze the performance ...


Fabrication And Application Of A Polymer Neuromorphic Circuitry Based On Polymer Memristive Devices And Polymer Transistors, Robert A. Nawrocki Jan 2014

Fabrication And Application Of A Polymer Neuromorphic Circuitry Based On Polymer Memristive Devices And Polymer Transistors, Robert A. Nawrocki

Electronic Theses and Dissertations

Neuromorphic engineering is a discipline that aims to address the shortcomings of today's serial computers, namely large power consumption, susceptibility to physical damage, as well as the need for explicit programming, by applying biologically-inspired principles to develop neural systems with applications such as machine learning and perception, autonomous robotics and generic artificial intelligence.

This doctoral dissertation presents work performed fabricating a previously developed type of polymer neuromorphic architecture, termed Polymer Neuromorphic Circuitry (PNC), inspired by the McCulloch-Pitts model of an artificial neuron. The major contribution of this dissertation is a development of processing techniques necessary to realize the Polymer ...


Dexterous Hexrotor Uav Platform, Guangying Jiang Nov 2013

Dexterous Hexrotor Uav Platform, Guangying Jiang

Electronic Theses and Dissertations

Mobile manipulation is a hot area of study in robotics as it unites the two classes of robots: locomotors and manipulators. An emerging niche in the field of mobile manipulation is aerial mobile manipulation. Although there has been a fair amount of study of free-flying satellites with graspers, the more recent trend has been to outfit UAVs with graspers to assist various manipulation tasks. While this recent work has yielded impressive results, it is hampered by a lack of appropriate testbeds for aerial mobile manipulation, similar to the state of ground-based mobile manipulation a decade ago. Typical helicopters or quadrotors ...


Human Action Recognition Via Fused Kinematic Structure And Surface Representation, Salah R. Althloothi Aug 2013

Human Action Recognition Via Fused Kinematic Structure And Surface Representation, Salah R. Althloothi

Electronic Theses and Dissertations

Human action recognition from visual data has remained a challenging problem in the field of computer vision and pattern recognition. This dissertation introduces a new methodology for human action recognition using motion features extracted from kinematic structure, and shape features extracted from surface representation of human body. Motion features are used to provide sufficient information about human movement, whereas shape features are used to describe the structure of silhouette. These features are fused at the kernel level using Multikernel Learning (MKL) technique to enhance the overall performance of human action recognition. In fact, there are advantages in using multiple types ...


Multiple Bounding Boxes Algorithm In Collision Detection And Its Performances In Sequential Vs Cuda Parallel Processing, Min Qi Jan 2013

Multiple Bounding Boxes Algorithm In Collision Detection And Its Performances In Sequential Vs Cuda Parallel Processing, Min Qi

Electronic Theses and Dissertations

The traditional method for detecting collisions in a 2D computer game uses a axisaligned bounding box around each sprite, and checks to determine if the bounding boxes overlap periodically. Using this single bounding box method may result in a large amount of pixel intersection tests, since a sprite may be composed of areas where the pixels are empty and the intersecting bounding box test results in false positives.

Our algorithm analysis shows that the optimal two or three bounding boxes is the best partition we can get for a reasonable time complexity. The results further show significantly diminishing returns for ...


Reducing Communication Delay Variability For A Group Of Robots, Goncalo Martins Jan 2013

Reducing Communication Delay Variability For A Group Of Robots, Goncalo Martins

Electronic Theses and Dissertations

A novel architecture is presented for reducing communication delay variability for a group of robots. This architecture relies on using three components: a microprocessor architecture that allows deterministic real-time tasks; an event-based communication protocol in which nodes transmit in a TDMA fashion, without the need of global clock synchronization techniques; and a novel communication scheme that enables deterministic communications by allowing senders to transmit without regard for the state of the medium or coordination with other senders, and receivers can tease apart messages sent simultaneously with a high probability of success. This approach compared to others, allows simultaneous communications without ...


Robot Team Formation Control Using Communication "Throughput Approach", Fatmazahra Ahmed Benhalim Jan 2013

Robot Team Formation Control Using Communication "Throughput Approach", Fatmazahra Ahmed Benhalim

Electronic Theses and Dissertations

In this thesis, we consider a team of robots forming a mobile robot network cooperating to accomplish a mission in an unknown but structured environment. The team has no a-priori knowledge of the environment. Robots have limited memory storage capabilities, not enough to map the environment. Each robot also has limited sensor capability and computational power. Due to the need to avoid obstacles and other environment effects, some robots get delayed from the rest. Using tracking controller, the robot team should follow the leader in a flexible formation shape without losing network connectivity, and that was achieved by monitoring the ...