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Electroacoustic Assessment Of Hearing Aids And Psaps, Manan Sheel Dec 2018

Electroacoustic Assessment Of Hearing Aids And Psaps, Manan Sheel

Electronic Thesis and Dissertation Repository

Hearing aids and personal sound amplification products (PSAPs) are commonly used assistive devices for treating hearing loss. Due to the diversity in the hardware and signal processing algorithms in these devices, comprehensive verification of their performance is essential. Existing standards for assistive hearing devices are primarily used for quality control purposes and do not quantify their performance in a perceptually-relevant manner. This thesis developed a comprehensive electroacoustic testing toolbox for hearing devices that encompasses both quality control and perceptually-relevant measures. In particular, a test sequence was developed to assess the effectiveness of noise reduction feature in assistive hearing devices. Several …


Objective Assessment Of Machine Learning Algorithms For Speech Enhancement In Hearing Aids, Krishnan Parameswaran Dec 2018

Objective Assessment Of Machine Learning Algorithms For Speech Enhancement In Hearing Aids, Krishnan Parameswaran

Electronic Thesis and Dissertation Repository

Speech enhancement in assistive hearing devices has been an area of research for many decades. Noise reduction is particularly challenging because of the wide variety of noise sources and the non-stationarity of speech and noise. Digital signal processing (DSP) algorithms deployed in modern hearing aids for noise reduction rely on certain assumptions on the statistical properties of undesired signals. This could be disadvantageous in accurate estimation of different noise types, which subsequently leads to suboptimal noise reduction. In this research, a relatively unexplored technique based on deep learning, i.e. Recurrent Neural Network (RNN), is used to perform noise reduction and …


Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai Dec 2018

Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai

Electronic Thesis and Dissertation Repository

IEEE 802.11ax, which is one emerging WLAN standard, aims at providing highly efficient communication in ultra-dense wireless networks. However, due to a large number of stations (STAs) in dense deployment scenarios and diverse services to be supported, there are many technical challenges to be overcome. Firstly, the potential high packet collision rate significantly degrades the network efficiency of WLAN. In this thesis, we propose an adaptive station (STA) grouping scheme to overcome this challenge in IEEE 802.11ax using Uplink OFDMA Random Access (UORA). In order to achieve optimal utilization efficiency of resource units (RUs), we first analyze the relationship between …


Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil Dec 2018

Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil

Electronic Thesis and Dissertation Repository

Time synchronization is an issue that affects data accuracy within wireless sensor networks (WSNs). This issue is due to the complex nature of the wireless medium and can be mitigated with accurate time synchronization. This research focuses on the Flooding Time Synchronization Protocol (FTSP) since it is considered as the gold standard for accuracy in WSNs. FTSP minimizes the synchronization error by executing an algorithm that creates a unified time for the network reporting micro-second accuracy. Most synchronization protocols use the FTSP implementation as a benchmark for comparison. The current and only FTSP implementation runs on the TinyOS platform and …


A Biomechanical And Physiological Signal Monitoring System For Four Degrees Of Upper Limb Movement, Allison R. Goldman Sep 2018

A Biomechanical And Physiological Signal Monitoring System For Four Degrees Of Upper Limb Movement, Allison R. Goldman

Electronic Thesis and Dissertation Repository

A lack of adherence to prescribed physical therapy regimens in improper healing results in poor outcomes for those affected by musculoskeletal disorders (MSDs) of the upper limb. Societal and psychological barriers to proper adherence can be addressed through the system presented in this work consisting of the following components: an ambulatory biosignal acquisition sleeve, an electromyography (EMG) based motion repetition detection algorithm, and the design of a compatible capacitive EMG acquisition module.

The biosignal acquisition sleeve was untethered, unobtrusive to motion, contained only modular components, and collected biomechanical and physiological sensor data to form full motion profiles of the following …


Non-Pilot Protection Of The Inverter-Dominated Ac Microgrid, Houman Lahiji Sep 2018

Non-Pilot Protection Of The Inverter-Dominated Ac Microgrid, Houman Lahiji

Electronic Thesis and Dissertation Repository

The main objective of this research is to develop reliable non-pilot protection and control strategies for the inverter-dominated microgrid. First, an improved Proportional-Derivative (PD) droop control strategy is proposed for enhanced disturbance response of the inverter-dominated AC microgrid. The proposed strategy significantly improves microgrid dynamic response and stability without requiring communication between distributed energy resources. Moreover, the impacts of large startup currents of induction motors on the stability and power quality of the inverter-dominated microgrid are investigates and recommendations for minimizing the associated adverse effects are made.

Subsequently, a fast, selective, and reliable protection strategy for the inverter-dominated microgrid is …


Optimization And Management Techniques For Geo-Distributed Sdn-Enabled Cloud Datacenters' Provisioning, Khaled M. Alhazmi Aug 2018

Optimization And Management Techniques For Geo-Distributed Sdn-Enabled Cloud Datacenters' Provisioning, Khaled M. Alhazmi

Electronic Thesis and Dissertation Repository

Cloud computing has become a business reality that impacts technology users around the world. It has become a cornerstone for emerging technologies and an enabler of future Internet services as it provides on-demand IT services delivery via geographically distributed data centers. At the core of cloud computing, virtualization technology has played a crucial role by allowing resource sharing, which in turn allows cloud service providers to offer computing services without discrepancies in platform compatibility.

At the same time, a trend has emerged in which enterprises are adopting a software-based network infrastructure with paradigms, such as software-defined networking, gaining further attention …


Recurrent Neural Network Architectures Toward Intrusion Detection, Wafaa Anani Aug 2018

Recurrent Neural Network Architectures Toward Intrusion Detection, Wafaa Anani

Electronic Thesis and Dissertation Repository

Recurrent Neural Networks (RNN) show a remarkable result in sequence learning, particularly in architectures with gated unit structures such as Long Short-term Memory (LSTM). In recent years, several permutations of LSTM architecture have been proposed mainly to overcome the computational complexity of LSTM. In this dissertation, a novel study is presented that will empirically investigate and evaluate LSTM architecture variants such as Gated Recurrent Unit (GRU), Bi-Directional LSTM, and Dynamic-RNN for LSTM and GRU specifically on detecting network intrusions. The investigation is designed to identify the learning time required for each architecture algorithm and to measure the intrusion prediction accuracy. …


Development Of Image-Based Surgical Planning Software For Bone-Conduction Implants, Carlos D. Salgado Aug 2018

Development Of Image-Based Surgical Planning Software For Bone-Conduction Implants, Carlos D. Salgado

Electronic Thesis and Dissertation Repository

The BONEBRIDGE bone-conduction device is used to treat conductive and mixed hearing losses. The size of its floating mass transducer (FMT) can preclude implantation in certain anatomies, necessitating comprehensive surgical planning. Current techniques are time consuming and difficult to transfer to the operating room. The objective of this thesis was to develop software for calculating skull thickness to the dura mater to find locations for the FMT and to the first air cells which guarantee sufficient bone for the implant screws to grasp. Temporal bone computed tomography (CT) images were segmented and processed and custom Matlab code was written to …


Development Of An Emg-Based Muscle Health Model For Elbow Trauma Patients, Emma Farago Aug 2018

Development Of An Emg-Based Muscle Health Model For Elbow Trauma Patients, Emma Farago

Electronic Thesis and Dissertation Repository

Musculoskeletal (MSK) conditions are a leading cause of pain and disability worldwide. Rehabilitation is critical for recovery from these conditions and for the prevention of long-term disability. Robot-assisted therapy has been demonstrated to provide improvements to stroke rehabilitation in terms of efficiency and patient adherence. However, there are no wearable robot-assisted solutions for patients with MSK injuries. One of the limiting factors is the lack of appropriate models that allow the use of biosignals as an interface input. Furthermore, there are no models to discern the health of MSK patients as they progress through their therapy.

This thesis describes the …


Investigation Of Opto-Mechanics In Thin-Film Photonic Crystal Membranes, Brett D. Poulsen Aug 2018

Investigation Of Opto-Mechanics In Thin-Film Photonic Crystal Membranes, Brett D. Poulsen

Electronic Thesis and Dissertation Repository

Opto-mechanical interactions in photonic crystals (PC) require further investigation for their realization in practical applications. In particular their dynamic response and opto-mechanical coupling is not well understood. The static response of a thin-film 2D PC membrane was studied and the mechanical sensitivity of a static pressure sensor was increased by a factor of 4.9 times. A novel model formulation, correctly accounting for the fluid-structure interaction and the influence of nano-features, was developed to describe the dynamic response of a thin-film 2D PC membrane. The model accurately predicted damping response to within 10% as compared to experimental measurements. A novel 2D …


Signal Identification In Discrete-Time Based On Internal-Model-Principle, Jie Chen Aug 2018

Signal Identification In Discrete-Time Based On Internal-Model-Principle, Jie Chen

Electronic Thesis and Dissertation Repository

This work presents an implementation of a signal identification algorithm which is based on the internal model principle. By using several internal models in feedback with a tuning function, this algorithm can decompose a signal into narrow-band signals and identify the frequencies, amplitudes and relative phases. A desired band-pass filter response can be achieved by selecting appropriate coefficients of the controllers and tuning functions, which can reject the noise and improve the performance. To achieve a result with fast transient characteristics, this system is then modified by adding a low-pass filter. This work is based on the previous work in …


Real-Time Intrusion Detection Using Multidimensional Sequence-To-Sequence Machine Learning And Adaptive Stream Processing, Gobinath Loganathan Aug 2018

Real-Time Intrusion Detection Using Multidimensional Sequence-To-Sequence Machine Learning And Adaptive Stream Processing, Gobinath Loganathan

Electronic Thesis and Dissertation Repository

A network intrusion is any unauthorized activity on a computer network. There are host-based and network-based Intrusion Detection Systems (IDS's), of which there are each signature-based and anomaly-based detection methods. An anomalous network behavior can be defined as an intentional violation of the expected sequence of packets. In a real-time network-based IDS, incoming packets are treated as a stream of data. A stream processor takes any stream of data or events and extracts interesting patterns on the fly. This representation allows applying statistical anomaly detection using sequence prediction algorithms as well as using a stream processor to perform signature-based intrusion …


Integration Of Rfid And Industrial Wsns To Create A Smart Industrial Environment, Ning Pan Jul 2018

Integration Of Rfid And Industrial Wsns To Create A Smart Industrial Environment, Ning Pan

Electronic Thesis and Dissertation Repository

A smart environment is a physical space that is seamlessly embedded with sensors, actuators, displays, and computing devices, connected through communication networks for data collection, to enable various pervasive applications. Radio frequency identification (RFID) and Wireless Sensor Networks (WSNs) can be used to create such smart environments, performing sensing, data acquisition, and communication functions, and thus connecting physical devices together to form a smart environment.

This thesis first examines the features and requirements a smart industrial environment. It then focuses on the realization of such an environment by integrating RFID and industrial WSNs. ISA100.11a protocol is considered in particular for …


Privacy-Protection In Cooperative Distributed Systems, Ali Saleh May 2018

Privacy-Protection In Cooperative Distributed Systems, Ali Saleh

Electronic Thesis and Dissertation Repository

The new form of digital computational capabilities and internet connectivity are promptly grow. This introduced a new form of computation that is emerging rapidly with cloud computing, mobile computing, wearable computing and the Internet-of-Things. All can be characterized as a class of “Cooperative Distributed Systems” (CDS) in open environment. A major drive of the growth involves massive number of people and organization, that has been engaged within their all daily life aspects and businesses activities. In this context, users’ privacy protection for a becoming crucial and essential requirement beyond the traditional approaches. This requires a formal treatment of “privacy …


Design Of An All-Dielectric Sublayer For Enhanced Transmittance In Stacked Antenna Array Applications, Matthew Bester May 2018

Design Of An All-Dielectric Sublayer For Enhanced Transmittance In Stacked Antenna Array Applications, Matthew Bester

Electronic Thesis and Dissertation Repository

In spatially constrained applications, the overlapping of antenna arrays can be unavoidable and its presence can lead to a blockage in the line-of-sight for the underlying antennas. Although previous investigations focused predominantly on the contribution of the ground plane and feed network-which were resolved through the use of frequency selective surfaces and proper feed network design, respectively-it is believed that the ground plane, substrate, and patch regions can emplace a substantial combined impedance. To rectify the transmission through these layers, an all-dielectric implementation is suggested based on the properties of complementary media and Fabry-Perot resonance shifting phenomena. Consequently, both spherical …


Performance Enhancement By Exploiting The Spatial Domain For Cost, Space And Spectrum Constraint 5g Communication, Golara Zafari Apr 2018

Performance Enhancement By Exploiting The Spatial Domain For Cost, Space And Spectrum Constraint 5g Communication, Golara Zafari

Electronic Thesis and Dissertation Repository

With everlasting increase of connectivity demand and high speed data communication, lots of progresses have been made to provide a sufficient quality of services (QoS). Several advanced technologies have been the cornerstone of this trend in academia as well as in industry. Nevertheless, there are some implementation challenges, which needs to be closely investigated. In this thesis, among all challenges, we elaborate on those related to number of radio frequency (RF) chains and resource scarcity.

The principle idea behind our proposed initial solution is to exploit the spatial domain as an additional degree of freedom. To be more specific, we …


Efficient Traffic Management Algorithms For The Core Network Using Device-To-Device Communication And Edge Caching, Hessam Yousefi Apr 2018

Efficient Traffic Management Algorithms For The Core Network Using Device-To-Device Communication And Edge Caching, Hessam Yousefi

Electronic Thesis and Dissertation Repository

Exponentially growing number of communicating devices and the need for faster, more reliable and secure communication are becoming major challenges for current mobile communication architecture. More number of connected devices means more bandwidth and a need for higher Quality of Service (QoS) requirements, which bring new challenges in terms of resource and traffic management. Traffic offload to the edge has been introduced to tackle this demand-explosion that let the core network offload some of the contents to the edge to reduce the traffic congestion. Device-to-Device (D2D) communication and edge caching, has been proposed as promising solutions for offloading data. D2D …


Simplified Numerical Models In Simulating Corona Discharge And Ehd Flows, Sara Mantach Apr 2018

Simplified Numerical Models In Simulating Corona Discharge And Ehd Flows, Sara Mantach

Electronic Thesis and Dissertation Repository

Corona discharge is used in many practical applications. For designing and optimization of corona devices, the discharge phenomenon should be numerically simulated. Most often, the corona discharge model is simplified by neglecting the process dynamics and assuming a limited number of reactions and species. In the extreme case, monopolar corona models with just one species and no reactions are studied. However, there is a problem with determining boundary conditions for the space charge density. The simplest solution to this problem was suggested by Kaptzov, who hypothesized that the electric field on the electrode surface remains constant and equal to the …


Novel Channel Estimation Techniques For Next Generation Mimo-Ofdm Wireless Communication Systems: Design And Performance Analysis, Mohammed Zourob Apr 2018

Novel Channel Estimation Techniques For Next Generation Mimo-Ofdm Wireless Communication Systems: Design And Performance Analysis, Mohammed Zourob

Electronic Thesis and Dissertation Repository

During the last decade, major evolutions were introduced for Multiple Input Multiple Output (MIMO) wireless communication systems. To reap the full benefits of MIMO systems, the Base Station (BS) and user equipments require accurate Channel State Information (CSI), which can be acquired using one of the two major approaches for Channel Estimation (CE): pilot-based or blind-based CE.

In this thesis, a pilot-based lower complexity channel estimator for Cell-Specific Reference Signals (C-RS) and User Equipment RS (UE-RS) in LTE-A Downlink (DL) system is proposed based on using a hybrid Wiener filter. The proposed system is a sub-optimum scheme that requires 8.8% …


Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen Apr 2018

Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen

Electronic Thesis and Dissertation Repository

Conjugated polymers are a class of electromechanically active materials that can produce motion in response to an electric potential. This motion can be harnessed to perform mechanical work, and therefore these materials are particularly well suited for use as sensors and actuators in microelectromechanical systems. Conventional methods to fabricate conjugated polymer actuators result in planar morphologies that limit fabricated devices to simplistic linear or bending actuation modes. To overcome this limitation, this work develops a conjugated polymer formulation and associated additive manufacturing method capable of realizing three-dimensional conductive polymer structures. A light-based additive manufacturing technique known as vat polymerization is …


Numerical Studies Of Electrohydrodynamic Flow Induced By Corona And Dielectric Barrier Discharges, Chaoao Shi Feb 2018

Numerical Studies Of Electrohydrodynamic Flow Induced By Corona And Dielectric Barrier Discharges, Chaoao Shi

Electronic Thesis and Dissertation Repository

Electrohyrodynamic (EHD) flow produced by gas discharges allows the control of airflow through electrostatic forces. Various promising applications of EHD can be considered, but this requires a deeper understanding of the physical mechanisms involved.

This thesis investigates the EHD flow generated by three forms of gas discharge. First, a multiple pin-plate EHD dryer associated with the positive corona discharge is studied using a stationary model. Second, the dynamics of a dielectric barrier discharge (DBD) plasma actuator is simulated with a time-dependent solver. Third, different configurations of the extended DBD are explored to enhance the EHD flow.

The results of the …


A High Gain Dc-Dc Full-Bridge Converter, Prashanth Prabhu Jan 2018

A High Gain Dc-Dc Full-Bridge Converter, Prashanth Prabhu

Electronic Thesis and Dissertation Repository

High gain DC-DC converters have become increasingly popular in recent years as there is greater need to interface low voltage DC sources such as solar cells and batteries with much higher voltage DC buses. A new high gain DC-DC converter with high gain, galvanic isolation and an integrated passive snubber network is proposed in the thesis. In the thesis, the general operation of the converter is discussed, its modes of operation are explained and its features are reviewed. The design of the converter is then discussed and a set of general guidelines that can be used in the design are …