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Full-Text Articles in Engineering

Power Management Strategies For Islanded Microgrids, Hisham Mahmood Dec 2014

Power Management Strategies For Islanded Microgrids, Hisham Mahmood

Electronic Thesis and Dissertation Repository

The focus of this thesis is on developing power management strategies for islanded microgrids, at the primary and the secondary hierarchal control layers. At the Primary Control Layer, the main objective of the proposed strategies is to achieve decentralized power management of Photovoltaic (PV) and battery storage in islanded microgrids. In contrast to the common approach of controlling the PV unit as a current source, in the proposed strategies, the PV unit is controlled as a voltage source that follows a multi-segment adaptive power/frequency characteristic curve. The strategies are implemented locally at the units using multi-loop controllers without relying on …


Posture-Dependent Projection-Based Force Reflection Algorithms For Bilateral Teleoperators, Ali Moatadelro Dec 2014

Posture-Dependent Projection-Based Force Reflection Algorithms For Bilateral Teleoperators, Ali Moatadelro

Electronic Thesis and Dissertation Repository

It was previously established that the projection-based force reflection (PBFR) algorithms improve the overall stability of a force reflecting teleoperation system. The idea behind the PBFR algorithms is to identify the component of the reflected force which is compensated by interaction with the operator's hand, and subsequently attenuate the residual component of the reflected force. If there is no a priori information regarding the behaviour of the human operator, the PBFR gain is selected equal to sufficiently small constant in order to guarantee stability for a wide range of human operator responses. Small PBRF gains, however, may deteriorate the transparency …


Design Of A Haptic Interface For Medical Applications Using Magneto-Rheological Fluid Based Actuators, Nima Najmaei Dec 2014

Design Of A Haptic Interface For Medical Applications Using Magneto-Rheological Fluid Based Actuators, Nima Najmaei

Electronic Thesis and Dissertation Repository

This thesis reports on the design, construction, and evaluation of a prototype two degrees-of-freedom (DOF) haptic interface, which takes advantage of Magneto-Rheological Fluid (MRF) based clutches for actuation. Haptic information provides important cues in teleoperated systems and enables the user to feel the interaction with a remote or virtual environment during teleoperation. The two main objectives in designing a haptic interface are stability and transparency. Indeed, deficiencies in these factors in haptics-enabled telerobotic systems has the introduction of haptics in medical environments where safety and reliability are prime considerations. An actuator with poor dynamics, high inertia, large size, and heavy …


Numerical Modeling Of Deformation, Oscillation, Spreading And Collision Characteristics Of Droplets In An Electric Field, Osameh Ghazian Dec 2014

Numerical Modeling Of Deformation, Oscillation, Spreading And Collision Characteristics Of Droplets In An Electric Field, Osameh Ghazian

Electronic Thesis and Dissertation Repository

Electric field induced flows, or electrohydrodynamics (EHD), have been promising in many fast-growing technologies, where droplet movement and deformation can be controlled to enhance heat transfer and mass transport. Several complex EHD problems existing in many applications were investigated in this thesis.

Firstly, this thesis presents the results of numerical simulations of the deformation, oscillation and breakup of a weakly conducting droplet suspended in an ambient medium with higher conductivity. It is the first time that the deformation of such a droplet was investigated numerically in a 3D configuration. We have determined three types of behavior for the droplets, which …


A Dc Distribution System For Power System Integration Of Plug-In Electric Vehicles; Modeling, Stability And Operation, Mansour Tabari Nov 2014

A Dc Distribution System For Power System Integration Of Plug-In Electric Vehicles; Modeling, Stability And Operation, Mansour Tabari

Electronic Thesis and Dissertation Repository

This thesis is mainly focused on (i) modeling of dc distribution systems for power system integration of plug-in electric vehicles (PEVs), (ii) proposing a method to enhance the stability of the dc distribution systems, and (iii) proposing an energy management strategy to control the power flow in the dc distribution system. The dc distribution system is expected to be more efficient and economical than a system of ac-dc battery chargers directly interfaced with an ac grid.

In the first part, a systematic method for developing a model for a dc distribution system, based on the configuration of the system is …


Monostatic Airborne Synthetic Aperture Radar Using Commercial Wimax Transceivers In The License-Exempt Spectrum, Kai Liu Nov 2014

Monostatic Airborne Synthetic Aperture Radar Using Commercial Wimax Transceivers In The License-Exempt Spectrum, Kai Liu

Electronic Thesis and Dissertation Repository

The past half-century witnessed an evolution of synthetic aperture radar (SAR). Boosted by digital signal processing (DSP), a variety of SAR imaging algorithms have been developed, in which the wavenumber domain algorithm is mature for airborne SAR and independent of signal waveforms. Apart from the algorithm development, there is a growing interest in how to acquire the raw data of targets’ echoes before the DSP for SAR imaging in a cost-effective way. For the data acquisition, various studies over the past 15 years have shed light on utilizing the signal generated from the ubiquitous broadband wireless technology – orthogonal frequency …


A Collaborative Access Control Model For Shared Items In Online Social Networks, Hanaa Al Shareef Nov 2014

A Collaborative Access Control Model For Shared Items In Online Social Networks, Hanaa Al Shareef

Electronic Thesis and Dissertation Repository

The recent emergence of online social networks (OSNs) has changed the communication behaviors of thousand of millions of users. OSNs have become significant platforms for connecting users, sharing information, and a valuable source of private and sensitive data about individuals. While OSNs insert constantly new social features to increase the interaction between users, they, unfortunately, offer primitive access control mechanisms that place the burden of privacy policy configuration solely on the holder who has shared data in her/his profile regardless of other associated users, who may have different privacy preferences. Therefore, current OSN privacy mechanisms violate the privacy of all …


Characterization Of A Contact-Stylus Surface Digitization Method Using Collaborative Robots: Accuracy Evaluation In The Context Of Shoulder Replacement Or Resurfacing, Sara Saud Zimmo Sep 2014

Characterization Of A Contact-Stylus Surface Digitization Method Using Collaborative Robots: Accuracy Evaluation In The Context Of Shoulder Replacement Or Resurfacing, Sara Saud Zimmo

Electronic Thesis and Dissertation Repository

Total shoulder arthroplasty (TSA) is the third most common joint replacement. While robot-assisted hip and knee replacement technologies have enjoyed extensive development, this has been limited in the upper limb. This work focused on quantifying the localization accuracy of a robotic system, and evaluating its efficacy in the context of TSA.

A collaborative robot was fitted with a stylus tip to perform manual surface digitizations using the robot’s encoder output. In the first experiment, two precision-machined master cubes, representing the working volume around a glenoid structure, were used for system validation. Next, cadaveric glenoids were digitized and compared to a …


Development And Integration Of Mems Based Inductive Sensors, Luyang Zhang Sep 2014

Development And Integration Of Mems Based Inductive Sensors, Luyang Zhang

Electronic Thesis and Dissertation Repository

Inductive sensors are one of the most widely used sensors especially in automotive. However, with the current PCB manufacture process, the large size of the sensor limits its usage in different applications. In this thesis, a novel method of fabricating bi-layer copper micro inductive sensor is demonstrated to solve the size issue. The two coil layers were built by UV LIGA process respectively, and a polyimide insulation film sandwiched in between. At the beginning, seeding layer was deposited on the substrate as electrode, and then the copper coil layer was created through electroplating in the patterned micromold. The coil was …


A Multiple Bit Parity Fault Detection Scheme For The Advanced Encryption Standard Galois/Counter Mode, Amir Hossein Ali Kouzeh Geran Sep 2014

A Multiple Bit Parity Fault Detection Scheme For The Advanced Encryption Standard Galois/Counter Mode, Amir Hossein Ali Kouzeh Geran

Electronic Thesis and Dissertation Repository

The Advanced Encryption Standard (AES) is a symmetric-key block cipher for electronic data announced by the U.S. National Institute of Standards and Technology (NIST) in 2001. The encryption process is based on symmetric key (using the same key for both encryption and decryption) for block encryption of 128, 192, and 256 bits in size. AES and its standardized authentication Galois/Counter Mode (GCM) have been adopted in numerous security-based applications. GCM is a mode of operation for AES symmetric key cryptographic block ciphers, which has been selected for its high throughput rates in high speed communication channels. The GCM is an …


Optimal Sizing And Power Management Strategies Of Islanded Microgrids For Remote Electrification Systems, Faruk A. Bhuiyan Sep 2014

Optimal Sizing And Power Management Strategies Of Islanded Microgrids For Remote Electrification Systems, Faruk A. Bhuiyan

Electronic Thesis and Dissertation Repository

Over the past few years, electrification of remote communities with an efficient utilization of on-site energy resources has entered a new phase of evolution. However, the planning tools and studies for the remote microgrids are considered inadequate. Moreover, the existing techniques have not taken into account the impact of reactive power on component sizes. Thus, this thesis concentrates on optimal sizing design of an islanded microgrid (IMG), which is composed of renewable energy resources (RERs), battery energy storage system (BESS), and diesel generation system (DGS), for the purpose of electrifying off-grid communities. Owing to the utilization of both BESS and …


Adaptive Relay Techniques For Ofdm-Based Cooperative Communication Systems, Xin Gao Aug 2014

Adaptive Relay Techniques For Ofdm-Based Cooperative Communication Systems, Xin Gao

Electronic Thesis and Dissertation Repository

Cooperative communication has been considered as a cost-effective manner to exploit the spatial diversity, improve the quality-of-service and extend transmission coverage. However, there are many challenges faced by cooperative systems which use relays to forward signals to the destination, such as the accumulation of multipath channels, complex resource allocation with the bidirectional asymmetric traffic and reduction of transmission efficiency caused by additional relay overhead. In this thesis, we aim to address the above challenges of cooperative communications, and design the efficient relay systems.

Starting with the channel accumulation problem in the amplify-and-forward relay system, we proposed two adaptive schemes for …


Comprehensive Statcom Control For Distribution And Transmission System Applications, Shubham Gupta Aug 2014

Comprehensive Statcom Control For Distribution And Transmission System Applications, Shubham Gupta

Electronic Thesis and Dissertation Repository

This thesis presents the development of a comprehensive STATCOM controller for load compensation, voltage regulation and voltage balancing in electric power distribution and transmission networks. The behavior of this controller is first validated with published results. Subsequently, the performance of this STATCOM controller is examined in a realistic Hydro One distribution feeder for accomplishing the compensation of both mildly and grossly unbalanced loads, and balancing of network voltages using PSCAD/EMTDC software. The STATCOM voltage control function is utilized for increasing the connectivity of wind plants in the same distribution feeder. The thesis further presents a frequency scanning technique for simple …


Fault Location In Series Compensated Transmission Lines, Tirath Pal Singh Bains Aug 2014

Fault Location In Series Compensated Transmission Lines, Tirath Pal Singh Bains

Electronic Thesis and Dissertation Repository

Due to the integration of modern technology such as electric vehicles, the emphasis is expected to shift from mechanical to electric power. Therefore, the need of increasing the power transmission capacity of the electric grid gets highlighted. Since, the construction of transmission lines is a tedious task owing to legalities, environmental impacts and high costs, the series compensated transmission lines are gaining popularity due to lesser costs and faster construction time. The series capacitor compensated transmission lines are very crucial lines due to the greater power being transmitted through them. Therefore, an accurate fault location becomes a prerequisite for limiting …


A Phase-Angle Tracking Method For Synchronization Of Single- And Three-Phase Grid-Connected Converters, Farzam Baradarani Aug 2014

A Phase-Angle Tracking Method For Synchronization Of Single- And Three-Phase Grid-Connected Converters, Farzam Baradarani

Electronic Thesis and Dissertation Repository

This thesis proposes a phase-angle tracking method, i.e., based on discrete Fourier transform for synchronization of three-phase and single-phase power-electronic converters under distorted and variable-frequency conditions. The proposed methods are designed based on fixed sampling rate and, thus, they can simply be employed for control applications. For three-phase applications, first, analytical analysis are presented to determine the errors associated with the phasor estimation using standard full-cycle discrete Fourier transform in a variable-frequency environment. Then, a robust phase-angle estimation technique is proposed, which is based on a combination of estimated positive and negative sequences, tracked frequency, and two proposed compensation coefficients. …


Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis Aug 2014

Automated Image Interpretation For Science Autonomy In Robotic Planetary Exploration, Raymond Francis

Electronic Thesis and Dissertation Repository

Advances in the capabilities of robotic planetary exploration missions have increased the wealth of scientific data they produce, presenting challenges for mission science and operations imposed by the limits of interplanetary radio communications. These data budget pressures can be relieved by increased robotic autonomy, both for onboard operations tasks and for decision- making in response to science data.

This thesis presents new techniques in automated image interpretation for natural scenes of relevance to planetary science and exploration, and elaborates autonomy scenarios under which they could be used to extend the reach and performance of exploration missions on planetary surfaces.

Two …


Evaluating Human Performance For Image-Guided Surgical Tasks, Matthew Kenneth Kramers Aug 2014

Evaluating Human Performance For Image-Guided Surgical Tasks, Matthew Kenneth Kramers

Electronic Thesis and Dissertation Repository

The following work focuses on the objective evaluation of human performance for two different interventional tasks; targeted prostate biopsy tasks using a tracked biopsy device, and external ventricular drain placement tasks using a mobile-based augmented reality device for visualization and guidance. In both tasks, a human performance methodology was utilized which respects the trade-off between speed and accuracy for users conducting a series of targeting tasks using each device. This work outlines the development and application of performance evaluation methods using these devices, as well as details regarding the implementation of the mobile AR application. It was determined that the …


Estimation Of Hidden Markov Models And Their Applications In Finance, Anton Tenyakov Aug 2014

Estimation Of Hidden Markov Models And Their Applications In Finance, Anton Tenyakov

Electronic Thesis and Dissertation Repository

Movements of financial variables exhibit extreme fluctuations during periods of economic crisis and times of market uncertainty. They are also affected by institutional policies and intervention of regulatory authorities. These structural changes driving prices and other economic indicators can be captured reasonably by models featuring regime-switching capabilities. Hidden Markov models (HMM) modulating the model parameters to incorporate such regime-switching dynamics have been put forward in recent years, but many of them could still be further improved. In this research, we aim to address some of the inadequacies of previous regime-switching models in terms of their capacity to provide better forecasts …


Online Virtual Network Provisioning In Distributed Cloud Computing Data Centers, Khaled Mefarh Alhazmi Aug 2014

Online Virtual Network Provisioning In Distributed Cloud Computing Data Centers, Khaled Mefarh Alhazmi

Electronic Thesis and Dissertation Repository

Efficient virtualization methodologies constitute the core of cloud computing data center implementation. Clients are attracted to the cloud model by the ability to scale available resources dynamically and the flexibility in payment options. However, performance hiccups can push them to return to the buy-and-maintain model. Virtualization plays a key role in the synchronous management of the thousands of servers along with clients' data residing on them. To achieve seamless virtualization, cloud providers require a system that performs the function of virtual network mapping. This includes receiving the cloud client requests and allocating computational and network resources in a way that …


A Cfd Assisted Control System Design For Supercritical Water Cooled Reactor, Rohit V. Maitri Jul 2014

A Cfd Assisted Control System Design For Supercritical Water Cooled Reactor, Rohit V. Maitri

Electronic Thesis and Dissertation Repository

In this study, the methodology to construct a control system based on computational fluid dynamics (CFD) simulations is developed for supercritical water cooled reactor (SCWR). The CFD model using Reynolds Stress Model (RSM) and k-w SST model is validated with the experimental cases of steady state and vertically up flowing supercritical water in circular tubes for normal heat transfer and deteriorated heat transfer (DHT) cases. This model is extended to simulate the transient thermal-hydraulic behaviour of supercritical fluid flow and heat transfer, and the results are also compared with the 1-D numerical model, THRUST. The DHT phenomenon is investigated using …


Human Metaphase Chromosome Analysis Using Image Processing, Akila M.S Subasinghe Arachchige Jul 2014

Human Metaphase Chromosome Analysis Using Image Processing, Akila M.S Subasinghe Arachchige

Electronic Thesis and Dissertation Repository

Development of an effective human metaphase chromosome analysis algorithm can optimize expert time usage by increasing the efficiency of many clinical diagnosis processes. Although many methods exist in the literature, they are only applicable for limited morphological variations and are specific to the staining method used during cell preparation. They are also highly influenced by irregular chromosome boundaries as well as the presence of artifacts such as premature sister chromatid separation.

Therefore an algorithm is proposed in this research which can operate with any morphological variation of the chromosome across images from multiple staining methods. The proposed algorithm is capable …


Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia Jun 2014

Plasmonic Optical Sensors: Performance Analysis And Engineering Towards Biosensing, Peipei Jia

Electronic Thesis and Dissertation Repository

Surface plasmon resonance (SPR) sensing for quantitative analysis of chemical reactions and biological interactions has become one of the most promising applications of plasmonics. This thesis focuses on performance analysis for plasmonic sensors and implementation of plamonic optical sensors with novel nanofabrication techniques.

A universal performance analysis model is established for general two-dimensional plasmonic sensors. This model is based on the fundamental facts of surface plasmon theory. The sensitivity only depends on excitation light wavelength as well as dielectric properties of metal and dielectrics. The expression involves no structure-specified parameters, which validates this formula in broad cases of periodic, quasiperiodic …


Protecting Personal Private Information In Collaborative Environments, David S. Allison Jun 2014

Protecting Personal Private Information In Collaborative Environments, David S. Allison

Electronic Thesis and Dissertation Repository

The ability to collaborate has always been vitally important to businesses and enterprises. With the availability of current networking and computing power, the creation of Collaborative Working Environments (CWEs) has allowed for this process to occur anytime over any geographical distance. Sharing information between individuals through collaborative environments creates new challenges in privacy protection for organizations and the members of organizations. This thesis confronts the problems when attempting to protect the personal private information of collaborating individuals.

In this thesis, a privacy-by-policy approach is taken to addressing the issue of protecting private information within collaborative environments. A privacy-by-policy approach to …


Design And Development Of Magneto-Rheological Actuators With Application In Mobile Robotics, Wenjun Li May 2014

Design And Development Of Magneto-Rheological Actuators With Application In Mobile Robotics, Wenjun Li

Electronic Thesis and Dissertation Repository

In recent years, Magneto-Rheological (MR) fluids devices are widely studied and used for various purposes. Among these MR fluids devices, the MR actuator has attracted increasing attention for last two decades. An MR actuator is usually made of an active component (motor) and MR clutches. Compared with the regular actuators, the MR actuator features compliance due to the existence of MR fluids, which is commonly consider as benefits at the aspect of safety. On the other hand, the MR actuator has advantages on controllable bandwidth, torque-mass and torque-inertia ratios compared with the other compliant actuators.

In this study, a new …


Oriented Collagen And Applications Of Waveguide Evanescent Field Scattering (Wefs) Microscopy, Qamrun Nahar Apr 2014

Oriented Collagen And Applications Of Waveguide Evanescent Field Scattering (Wefs) Microscopy, Qamrun Nahar

Electronic Thesis and Dissertation Repository

In this thesis, Waveguide Evanescent Field Scattering (WEFS) microscopy is developed as a non-invasive, label-free live cell imaging technique. This new high-contrast imaging can be employed to study the first hundred nanometers from the surface as it utilizes the evanescent field of a waveguide as the illumination source. Previously, waveguide evanescent field fluorescence (WEFF) microscopy was developed as a fluorescence imaging technique comparable to the total internal reflection fluorescent (TIRF) microscopy. Both the WEFF and WEFS technique utilizes the same fundamental concepts except in WEFS microscopy imaging is accomplished without the application of any fluorescent labeling. In this work, bacterial …


Design Of Analog Cmos Circuits For Batteryless Implantable Telemetry Systems, Kyle G. A. De Gannes Apr 2014

Design Of Analog Cmos Circuits For Batteryless Implantable Telemetry Systems, Kyle G. A. De Gannes

Electronic Thesis and Dissertation Repository

A wireless biomedical telemetry system is a device that collects biomedical signal measurements and transmits data through wireless RF communication. Testing medical treatments often involves experimentation on small laboratory animals, such as genetically modified mice and rats. Using batteries as a power source results in many practical issues, such as increased size of the implant and limited operating lifetime. Wireless power harvesting for implantable biomedical devices removes the need for batteries integrated into the implant. This will reduce device size and remove the need for surgical replacement due to battery depletion. Resonant inductive coupling achieves wireless power transfer in a …


Modeling And Control Of Steerable Ablation Catheters, Mahta Khoshnam Tehrani Apr 2014

Modeling And Control Of Steerable Ablation Catheters, Mahta Khoshnam Tehrani

Electronic Thesis and Dissertation Repository

Catheters are long, flexible tubes that are extensively used in vascular and cardiac interventions, e.g., cardiac ablation, coronary angiography and mitral valve annuloplasty. Catheter-based cardiac ablation is a well-accepted treatment for atrial fibrillation, a common type of cardiac arrhythmia. During this procedure, a steerable ablation catheter is guided through the vasculature to the left atrium to correct the signal pathways inside the heart and restore normal heart rhythm. The outcome of the ablation procedure depends mainly on the correct positioning of the catheter tip at the target location inside the heart and also on maintaining a consistent contact between the …


Contextual Anomaly Detection Framework For Big Sensor Data, Michael Hayes Apr 2014

Contextual Anomaly Detection Framework For Big Sensor Data, Michael Hayes

Electronic Thesis and Dissertation Repository

Performing predictive modelling, such as anomaly detection, in Big Data is a difficult task. This problem is compounded as more and more sources of Big Data are generated from environmental sensors, logging applications, and the Internet of Things. Further, most current techniques for anomaly detection only consider the content of the data source, i.e. the data itself, without concern for the context of the data. As data becomes more complex it is increasingly important to bias anomaly detection techniques for the context, whether it is spatial, temporal, or semantic. The work proposed in this thesis outlines a contextual anomaly detection …


Biomechanical Modeling And Inverse Problem Based Elasticity Imaging For Prostate Cancer Diagnosis, Seyed Reza Mousavi Apr 2014

Biomechanical Modeling And Inverse Problem Based Elasticity Imaging For Prostate Cancer Diagnosis, Seyed Reza Mousavi

Electronic Thesis and Dissertation Repository

Early detection of prostate cancer plays an important role in successful prostate cancer treatment. This requires screening the prostate periodically after the age of 50. If screening tests lead to prostate cancer suspicion, prostate needle biopsy is administered which is still considered as the clinical gold standard for prostate cancer diagnosis. Given that needle biopsy is invasive and is associated with issues including discomfort and infection, it is desirable to develop a prostate cancer diagnosis system that has high sensitivity and specificity for early detection with a potential to improve needle biopsy outcome. Given the complexity and variability of prostate …


Adaptive Real-Time Optimal Dispatch Of Privately Owned Energy Storage Systems, Hadi Khani Apr 2014

Adaptive Real-Time Optimal Dispatch Of Privately Owned Energy Storage Systems, Hadi Khani

Electronic Thesis and Dissertation Repository

In this thesis, a real-time optimal dispatching (RTOD) algorithm is developed by formulating a mixed integer linear programming problem to determine charging and discharging power set-points of a privately owned energy storage system (ESS) in a competitive electricity market. The objective of the optimization problem is to generate revenue by exploiting price volatility in the day-ahead/week-ahead market. Moreover, this thesis aims to evaluate and improve the usefulness of publicly available electricity market prices for RTOD of a privately owned ESS in a competitive electricity market by developing a new adaptive technique. The pre-dispatch and the corresponding ex-post hourly Ontario energy …