Computer Engineering Commons^™

Computation Offloading Decisions For Reducing Completion Time, Salvador Melendez

Open Access Theses & Dissertations

Mobile devices are being widely used in many applications such as image processing, computer vision (e.g. face detection and recognition), wearable computing, language translation, and battlefield operations. However, mobile devices are constrained in terms of their battery life, processor performance, storage capacity, and network bandwidth. To overcome these issues, there is an approach called Computation Offloading, also known as cyber-foraging and surrogate computing. Computation offloading consists of migrating computational jobs from a mobile device to more powerful remote computing resources. Upon completion of the job, the results are sent back to the mobile device. However, a decision must be made; …

Project Maelstrom: Forensic Analysis Of The Bittorrent-Powered Browser, Jason Farina, M-Tahar Kechadi, Mark Scanlon

Journal of Digital Forensics, Security and Law

In April 2015, BitTorrent Inc. released their distributed peer-to-peer powered browser, Project Maelstrom, into public beta. The browser facilitates a new alternative website distribution paradigm to the traditional HTTP-based, client-server model. This decentralised web is powered by each of the visitors accessing each Maelstrom hosted website. Each user shares their copy of the website;s source code and multimedia content with new visitors. As a result, a Maelstrom hosted website cannot be taken offline by law enforcement or any other parties. Due to this open distribution model, a number of interesting censorship, security and privacy considerations are raised. This paper explores …

Mission-Aware Vulnerability Assessment For Cyber-Physical System, Xiaotian Wang

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Designing secure cyber-physical systems (CPS) is fundamentally important. An indispensable step towards this end is to perform vulnerability assessment. This thesis discusses the design and implementation of a mission-aware CPS vulnerability assessment framework. The framework intends to accomplish three objectives including i) mapping CPS mission into infrastructural components, ii) evaluating global impact of each vulnerability, and iii) achieving verifiable results and high flexibility. In order to accomplish these objectives, a model-based analysis strategy is employed. Specifically, a CPS simulator is used to model dynamic behaviors of CPS components under different missions; the framework facilitates a bottom-up approach to traverse a …

Automatic Emotion Identification From Text, Wenbo Wang

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People's emotions can be gleaned from their text using machine learning techniques to build models that exploit large self-labeled emotion data from social media. Further, the self-labeled emotion data can be effectively adapted to train emotion classifiers in different target domains where training data are sparse.

Emotions are both prevalent in and essential to most aspects of our lives. They influence our decision-making, affect our social relationships and shape our daily behavior. With the rapid growth of emotion-rich textual content, such as microblog posts, blog posts, and forum discussions, there is a growing need to develop algorithms and techniques for …

A Language For Inconsistency-Tolerant Ontology Mapping, Kunal Sengupta

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Ontology alignment plays a key role in enabling interoperability among various data sources present in the web. The nature of the world is such, that the same concepts differ in meaning, often so slightly, which makes it difficult to relate these concepts. It is the omni-present heterogeneity that is at the core of the web. The research work presented in this dissertation, is driven by the goal of providing a robust ontology alignment language for the semantic web, as we show that description logics based alignment languages are not suitable for aligning ontologies.

The adoption of the semantic web technologies …

Orthogonal Moment-Based Human Shape Query And Action Recognition From 3d Point Cloud Patches, Huaining Cheng

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With the recent proliferation of 3D sensors such as Light Detection and Ranging (LIDAR), it is essential to develop feature representation methods that can best characterize the point clouds produced by these devices. When these devices are employed in targeting and surveillance of human actions from both ground and aerial platforms, the corresponding point clouds of body shape often comprise low-resolution, disjoint, and irregular patches of points resulted from self-occlusions and viewing angle variations. The prevailing method of depth image analysis has the limitation of relying on 2D features that are not native representation of 3D spatial relationships. On the …

Ontology Pattern-Based Data Integration, Adila Alfa Krisnadhi

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Data integration is concerned with providing a unified access to data residing at multiple sources. Such a unified access is realized by having a global schema and a set of mappings between the global schema and the local schemas of each data source, which specify how user queries at the global schema can be translated into queries at the local schemas. Data sources are typically developed and maintained independently, and thus, highly heterogeneous. This causes difficulties in integration because of the lack of interoperability in the aspect of architecture, data format, as well as syntax and semantics of the data. …

Learning To Rank Algorithms And Their Application In Machine Translation, Tian Xia

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In this thesis, we discuss two issues in the learning to rank area, choosing effective objective loss function, constructing effective regresstion trees in the gradient boosting framework, as well as a third issus, applying learning to rank models into statistcal machine translation. First, list-wise based learning to rank methods either directly optimize performance measures or optimize surrogate functions of performance measures that have smaller gaps between optimized losses and performance measures, thus it is generally believed that they should be able to lead to better performance than point-and pair-wise based learning to rank methods. However, in real-world applications, state-of-the-art practical …

Sheep Updates 2015 - Merredin, Bruce Mullan, Kate Pritchett, Kimbal Curtis, Chris Wilcox, Lynne Bradshaw, Geoff Lindon, Katherine Davies, Joe Young, Stephen Lee, Dawson Bradford, Khama Kelman, Lucy Anderton, Jaq Pearson, Jackie Jarvis, Ben Patrick

Sheep Updates

This session covers fourteen papers from different authors:

1. The Sheep Industry Business Innovation project, Bruce Mullan, Sheep Industry Development Director, Department of Agriculture and Food, Western Australia

2. Western Australian sheep stocktake, Kate Pritchett and Kimbal Curtis, Research Officers, Department of Agriculture and Food, Western Australia

3. Wool demand and supply - short term volatility, long term opportunities, Chris Wilcox, Principal of Poimena Analysis

4. Myths, Facts and the role of animal welfare in farming, Lynne Bradshaw, president, RSPCA WA

5. Latest research and development on breech strike prevention, Geoff Lindon, Manager Productivity and Animal Welfare, AWI

6. …

Stargrazer One: A New Architecture For Distributed Maximum Power Point Tracking Of Solar Photovoltaic Sources, Edgard Munoz-Coreas

Theses and Dissertations--Electrical and Computer Engineering

The yield from a solar photovoltaic (PV) source is dependent on factors such as light and temperature. A control system called a maximum power point tracker (MPPT) ensures that the yield from a solar PV source is maximized in spite of these factors. This thesis presents a novel implementation of a perturb and observe (PO) MPPT.

The implementation uses a switched capacitor step down converter and a custom digital circuit implementation of the PO algorithm. Working in tandem, the switched capacitor step down converter and the custom digital circuit implementation were able to successfully track the maximum power point of …

Browser Based Visualization For Parameter Spaces Of Big Data Using Client-Server Model, Kurtis M. Glendenning

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Visualization is an important task in data analytics, as it allows researchers to view abstract patterns within the data instead of reading through extensive raw data. Allowing the ability to interact with the visualizations is an essential aspect since it provides the ability to intuitively explore data to find meaning and patterns more efficiently. Interactivity, however, becomes progressively more difficult as the size of the dataset increases. This project begins by leveraging existing web-based data visualization technologies and extends their functionality through the use of parallel processing. This methodology utilizes state-of-the-art techniques, such as Node.js, to split the visualization rendering …

Owl Query Answering Using Machine Learning, Todd Huster

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The formal semantics of the Web Ontology Language (OWL) enables automated reasoning over OWL knowledge bases, which in turn can be used for a variety of purposes including knowledge base development, querying and management. Automated reasoning is usually done by means of deductive (proof-theoretic) algorithms which are either provably sound and complete or employ approximate methods to trade some correctness for improved efficiency. As has been argued elsewhere, however, reasoning methods for the Semantic Web do not necessarily have to be based on deductive methods, and approximate reasoning using statistical or machine-learning approaches may bring improved speed while maintaining high …

Temporally Biased Search Result Snippets, J. Abhiram Tatineni

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The search engine result snippets are an important source of information for the user to obtain quick insights into the corresponding result documents. When the search terms are too general, like a person's name or a company's name, creating an appropriate snippet that effectively summarizes the document's content can be challenging owing to multiple occurrences of the search term in the top ranked documents, without a simple means to select a subset of sentences containing them to form result snippet. In web pages classified as narratives and news articles, multiple references to explicit, implicit and relative temporal expressions can be …

Design Of A Novel Low - Cost, Portable, 3d Ultrasound System With Extended Imaging Capabilities For Point-Of-Care Applications, Michail Tsakalakis

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Ultrasound Imaging (USI) or Medical Sonography (MS), as it is formally called, has been widely used in biomedical applications over the last decades. USI can provide clinicians with a thorough view of the internal parts of the human body, making use of sound waves of higher frequencies than humans can perceive. USI systems are considered highly portable and of low-cost, compared to other imaging modalities. However, despite those advantages, Ultrasound Systems (US) and especially 3D ones, have not been yet extensively utilized for Point-of-Care (POC) applications, due to numerous restrictions and artifacts that they currently present.

Hardware complexity and real-time …

Mining Behavior Of Citizen Sensor Communities To Improve Cooperation With Organizational Actors, Hemant Purohit

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Web 2.0 (social media) provides a natural platform for dynamic emergence of citizen (as) sensor communities, where the citizens generate content for sharing information and engaging in discussions. Such a citizen sensor community (CSC) has stated or implied goals that are helpful in the work of formal organizations, such as an emergency management unit, for prioritizing their response needs. This research addresses questions related to design of a cooperative system of organizations and citizens in CSC. Prior research by social scientists in a limited offline and online environment has provided a foundation for research on cooperative behavior challenges, including 'articulation' …

Tunable Absorption Based On Plasmonic Nanostructures Loaded With Graphene, Christos Argyropoulos

Department of Electrical and Computer Engineering: Faculty Publications

We present simulations of a hybrid graphene-plasmonic device constituted by periodic metallic nanowires placed over a dielectric spacer layer and a metallic film. The spacer layer is composed of a thin silica layer combined with an one-atom-thick graphene sheet. An electrically controlled ultra-compact absorption modulator can be realized based on the proposed theoretical device.

Robust Optimization For Bidirectional Dispatch Coordination Of Large-Scale V2g, Xiaoqing Bai, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a robust optimization (RO) model for bidirectional dispatch coordination of large-scale plugin electric vehicles (PEVs) in a power grid in which the PEVs are aggregated to manage. The PEV aggregators are considered as a type of dispatchable demand response and energy storage resource with stochastic behaviors, and can supply load or provide ancillary services such as regulation reserve to the grid. The proposed RO model is then reformulated as a mixedinteger quadratic programming model, which can be solved efficiently. Computer simulations are performed for a power grid with ten generators and three PEV aggregators to validate the …

Optimal Bidding Strategy Of A Strategic Wind Power Producer In The Short-Term Market, Ting Dai, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Wind energy is a clean and renewable energy source which is rapidly growing globally. As the penetration level of wind power grows, the system operators need to consider wind power producers as strategic producers whose bidding behaviors will have an impact on the locational marginal prices. This paper proposes a bilevel stochastic optimization model to obtain the optimal bidding strategy for a strategic wind power producer in the short-term electricity market. The upper level problem of the model maximizes the profit of the wind power producer, while the lower level problem represents the market clearing processes of both day-ahead and …

Multiobjective Optimization Of Switched Reluctance Motors Based On Design Of Experiments And Particle Swarm Optimization, Cong Ma, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a comprehensive framework for multiobjective design optimization of switched reluctance motors (SRMs) based on a combination of the design of experiments and particle swarm optimization (PSO) approaches. First, the definitive screening design was employed to perform sensitivity analyses to identify significant design variables without bias of interaction effects between design variables. Next, optimal third-order response surface (RS) models were constructed based on the Audze–Eglais Latin hypercube design using the selected significant design variables. The constructed optimal RS models consist of only significant regression terms, which were selected by using PSO. Then, a PSO-based multiobjective optimization coupled with …

A Survey On Wind Turbine Condition Monitoring And Fault Diagnosis−Part I: Components And Subsystems, Deli Qiao, Dingguo Lu

Department of Electrical and Computer Engineering: Faculty Publications

This paper provides a comprehensive survey on the state-of-the-art condition monitoring and fault diagnostic technologies for wind turbines. The Part I of this survey briefly reviews the existing literature surveys on the subject, discusses the common failure modes in the major wind turbine components and subsystems, briefly reviews the condition monitoring and fault diagnostic techniques for these components and subsystems, and specifically discusses the issues of condition monitoring and fault diagnosis for offshore wind turbines.

A Survey On Wind Turbine Condition Monitoring And Fault Diagnosis−Part Ii: Signals And Signal Processing Methods, Wei Qiao, Dingguo Lu

Department of Electrical and Computer Engineering: Faculty Publications

This paper provides a comprehensive survey on the state-of-the-art condition monitoring and fault diagnostic technologies for wind turbines. The Part II of this survey focuses on the signals and signal processing methods used for wind turbine condition monitoring and fault diagnosis.

A Real-Time Information Based Demand-Side Management System In Smart Grid, Feng Ye, Yi Qian, Rose Qingyang Hu

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, we study a real-time information based demand-side management (DSM) system with advanced communication networks in smart grid. DSM can smooth peakto- average ratio (PAR) of power usage in the grid, which in turn reduces the waste of fuel and the emission of greenhouse gas. We first target to minimize PAR with a centralized scheme. To motivate power suppliers, we further propose another centralized scheme targeting minimum power generation cost. However, customers may not be motivated by a centralized scheme since such a scheme requires total control and privacy from them. A centralized scheme also requires too much …

An Isolated Three-Port Bidirectional Dc-Dc Converter For Photovoltaic Systems With Energy Storage, Jianwu Zeng, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper proposes a new isolated, three-port, bidirectional, DC-DC converter for simultaneous power management of multiple energy sources. The proposed converter has the advantage of using the least number of switches and soft switching for the main switch, which is realized by using a LCL-resonant circuit. The converter is capable of interfacing sources of different voltage-current characteristics with a load and/or a DC microgrid. The proposed converter is constructed for simultaneous power management of a photovoltaic (PV) panel, a rechargeable battery, and a load. Simulation and experimental results show that the proposed converter is capable of maximum power point tracking …

Modeling And Control Of A Three-Port Dc-Dc Converter For Pv-Battery Systems, Jianwu Zeng, Wei Qiao, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

This paper presents modeling and decoupled control design for an isolated three-port DC-DC converter (TPC), which interfaces a photovoltaic (PV) panel, a rechargeable battery, and an isolated load. A small signal model is derived from the state-space equations of the TPC. Based on the model, two decoupled controllers are designed to control the power flows of the two sources and the load voltage independently. Experimental studies are performed to verify that the two controllers are capable of regulating the power flows of the PV panel and the battery while maintaining a constant output voltage for the TPC.

Optimal Joint Transmission And Harvested Energy Scheduling For Renewable Energy Harvesting Enabled Cellular Network Under Coordinated Multi-Point Transmission, Zejue Wang, Hongjia Li, Dan Hu, Song Ci

Department of Electrical and Computer Engineering: Faculty Publications

On-grid energy consumption of base stations (BSs) contributes up a significant fraction of the total carbon dioxide (CO₂) emissions of cellular networks, among which remote radio units (RRUs) absorb most of the energy consumption. To eliminate the on-grid energy consumption and the corresponding CO₂ emission, we propose a new transmission framework, in which all RRUs and associated power amplifiers (PAs) are powered by hybrid energy sources including on-grid energy source and off-grid renewable energy source. Based on the framework, we pursue a systematic study on the joint transmission and harvested energy scheduling algorithm for the hybrid energy …

Cmi Analysis And Precoding Designs For Correlated Multi-Hop Mimo Channels, Nguyen N. Tran, Song Ci, Ha X. Nguyen

Department of Electrical and Computer Engineering: Faculty Publications

Conditional mutual information (CMI) analysis and precoding design for generally correlated wireless multi-hop multi-input multi-output (MIMO) channels are presented in this paper. Although some particular scenarios have been examined in existing publications, this paper investigates a generally correlated transmission system having spatially correlated channel, mutually correlated source symbols, and additive colored Gaussian noise (ACGN). First, without precoding techniques, we derive the optimized source symbol covariances upon mutual information maximization. Secondly, we apply a precoding technique and then design the precoder in two cases: maximizing the mutual information and minimizing the detection error. Since the optimal design for the end-to-end system …

Integral Equation Analysis Of Em Scattering From Multilayered Metallic Photonic Crystal Accelerated With Adaptive Cross Approximation, Jianxun Su, Zengrui Li, Xujin Yuan, Yaoqing (Lamar) Yang, Junhong Wang

Department of Electrical and Computer Engineering: Faculty Publications

A space-domain integral equation method accelerated with adaptive cross approximation (ACA) is presented for the fast and accurate analysis of electromagnetic (EM) scattering from multilayered metallic photonic crystal (MPC). The method directly solves for the electric field in order to easily enable the periodic boundary condition (PBC) in the spatial domain. The ACA is a purely algebraic method allowing the compression of fully populated matrices; hence, its formulation and implementation are independent of integral equation kernel (Green’s function).Therefore, the ACA is very well suited for accelerating integral equation analysis of periodic structure with the integral kernel of the periodic Green’s …

Drive Systems Including Sliding Mode Observers And Methods Of Controlling The Same, Long Wu, Yue Zhao, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

At least one example embodiment discloses a drive system including a motor including a rotor, the motor configured to receive a measured current, a controller configured to generate a Voltage command for the motor, a sliding mode observer configured to determine an estimated current for the motor based on the Voltage command, determine a difference between the measured current and the estimated current, and determine a Switching control vector and an estimator con figured to estimate a rotor position based on the Switching control vector, the Switching control vector being determined based on the difference and adaptive parameters of the …

Probes For Multidimensional Nanospectroscopic Imaging And Methods Of Fabrication Thereof, Alexander Weber-Bargionii, Stefano Cabrini, Wei Bao, Mauro Melli, Eli Yablonovitch, Peter J. Schuck

Department of Electrical and Computer Engineering: Faculty Publications

This disclosure provides systems, methods, and apparatus related to probes for multidimenisonal nanospectroscopic imaging. In one aspect, a method includes providing a transparent tip comprising a dielectric material. A four-sided pyramidal-shaped structure is formed at an apex of the transparent tip using a focus ion beam. Metal layers are deposited over two opposing sides of the four-sided pyramidal-shaped structure.

Table Of Contents

Journal of International Technology and Information Management

No abstract provided.