Computer Engineering Commons^™

Linked Open Data Alignment & Querying, Prateek Jain

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The recent emergence of the "Linked Data" approach for publishing data represents a major step forward in realizing the original vision of a web that can "understand and satisfy the requests of people and machines to use the web content" i.e. the Semantic Web. This new approach has resulted in the Linked Open Data (LOD) Cloud, which includes more than 295 large datasets contributed by experts belonging to diverse communities such as geography, entertainment, and life sciences. However, the current interlinks between datasets in the LOD Cloud, as we will illustrate,are too shallow to realize much of the benefits promised. …

Cloudvista: A Framework For Interactive Visual Cluster Exploration Of Big Data In The Cloud, Zhen Li

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With the development and deployment of ubiquitous information sensing, mobile devices,wireless sensor networks, RFID readers, simulation, and computer generated software logs, big data have become precious resources for scientific study, business intelligence, and national security. As one of the most intuitive and effective analysis methods,visual cluster analysis remains as a significant challenge for big datasets. First, existing visualization models need to be updated to process big data in parallel. Second, processing big data inevitably bring large latency, which conflicts the requirement of interactivity. In this thesis, we develop the CloudVista framework to address the common problems with data reduction methods …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Abstraction Driven Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu

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Cloud computing has changed the way organizations create, manage, and evolve their applications. While many organizations are eager to use the cloud, tempted by substantial cost savings and convenience, the implications of using clouds are still not well understood. One of the major concerns in cloud adoption is the vendor lock-in of applications, caused by the heterogeneity of the numerous cloud service offerings. Vendor locked applications are difficult, if not impossible to port from one cloud system to another, forcing cloud service consumers to use undesired or suboptimal solutions. This dissertation investigates a complete and comprehensive solution to address the …

Winding Resistance And Winding Power Loss Of High-Frequency Power Inductors, Rafal P. Wojda

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The scope of this research is concentrated on analytical winding size optimization (thickness or diameter) of high-frequency power inductors wound with foil, solid-round wire, multi-strand wire, and litz-wire conductors.

The first part of this research concerns analytical optimization of the winding size (thickness or diameter) for the inductors conducting a sinusoidal current. Estimation of winding resistance in individual inductor layers made of foil, taking into account the skin and proximity effects is performed. Approximated equations for the winding power loss in each layer are given and the optimal values of foil thickness for each layer are derived.

A low- and …

Optimization Of Spectrum Allocation In Cognitive Radio And Dynamic Spectrum Access Networks, Tao Zhang

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Spectrum has become a treasured commodity. However, many licensed frequency bands exclusively assigned to the primary license holders (also called primary users) remain relatively unused or under-utilized for most of the time. Allowing other users (also called secondary users) without a license to operate in these bands with no interference becomes a promising way to satisfy the fast growing needs for frequency spectrum resources. A cognitive radio adapts to the environment it operates in by sensing the spectrum and quickly decides on appropriate frequency bands and transmission parameters to use in order to achieve certain performance goals. One of the …

Enhancing Spectrum Utilization In Dynamic Cognitive Radio Systems, Dusadee Treeumnuk

Electrical & Computer Engineering Theses & Dissertations

Cognitive radio (CR) is regarded as a viable solution to enabling flexible use of the frequency spectrum in future generations of wireless systems by allowing unlicensed secondary users (SU) to access licensed spectrum under the specific condition that no harmful interference be caused to the licensed primary users (PU) of the spectrum. In practical scenarios, the knowledge of PU activity is unknown to CRs and radio environments are mostly imperfect due to various issues such as noise uncertainty and multipath fadings. Therefore, important functionalities of CR systems are to efficiently detect availability of radio spectrum as well as to avoid …

Broadband Brewster Transmission Through 2d Metallic Gratings, Khai Q. Le, Christos Argyropoulos, Nadia Mattiucci, Giuseppe D'Aguanno, Mark J. Bloemer, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

Recently, we have introduced a mechanism to achieve ultrabroadband light funnelling and total transmission through 1D narrow metallic gratings at a specific incidence angle, the so-called plasmonic Brewster angle. This phenomenon is based on impedance matching between the guided modes supported by ultranarrow linear slits and transverse-magnetic waves at oblique incidence. In this paper, we demonstrate that such phenomenon, representing the equivalent of Brewster transmission for plasmonic screens, can also occur in 2D metallic gratings of various structural forms and shapes, and that it may be made insensitive to the azimuthal, or polarization, angle u. This finding may have relevant …

An Adaptive Algorithm For Corrupted Images, Deborah D. Duran-Herrmann, Qilin Qi, Yaoqing Lamar Yang

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Noise is ever-present in communication channels and can produce devastating degradation to the images at the receiver end. In this paper, a novel approach to detecting different types of noise models in corrupted images is presented. Basically, it is a two-step process that has the ability to handle real-time applications due to its computational simplicity. The proposed algorithm handles error correction more efficiently in the second stage of processing, given a means to detect the type of noise present in the first stage. This algorithm will be verified and tested against existing methods on different noise models. Preliminary results show …

Automation Laboratory Development Focusing On Industrial Hands-On Experience, Simulation Software, And Application Research Projects, Cheng Y. Lin, John R. Hackworth

Engineering Technology Faculty Publications

This paper describes the development of an Automation Control Lab in the Department of Engineering Technology at the University. The lab facility includes pneumatic actuators/sensors, electrical relays/switches, and Programmable Logic Controllers (PLC). The major goal of the development is to help students gain hands-on industrial experience by conducting simple projects during the lecture hours and more advanced projects during the lab hours. Simulation software is also applied to reduce implementation time when developing complicated pneumatic circuits and PLC programs. In addition, three examples of industrial automation projects using PLC from the Technology Application Center (TAC) are also introduced to students …

Many-To-One Communication Protocol For Wireless Sensor Networks, Chansu Yu, Robert Fiske, Seungmin Park, Won-Tae Kim

Electrical and Computer Engineering Faculty Publications

This paper proposes a novel communication protocol, called Many-to-One Sensors-to-Sink (MOSS), tailored to wireless sensor networks (WSNs). It exploits the unique sensors-to-sink traffic pattern to realize low-overhead medium access and low- latency sensors-to-sink routing paths. In conventional schedule-based MAC protocols such as S-MAC, sensor nodes in the proximity of the event generate reports simultaneously, causing unreliable and unpredictable performance during a brief but critical period of time when an event of interest occurs. MOSS is based on time division multiple access (TDMA) that avoids energy waste due to collisions, idle listening and overhearing and avoids unreliable behavior mentioned above. A …

Computer Aided Design Algorithmic Technique For Very Large Scale Integrated Circuit Design And Smart Home Embedded System Design, Xiaodao Chen

Dissertations, Master's Theses and Master's Reports - Open

To tackle the challenges at circuit level and system level VLSI and embedded system design, this dissertation proposes various novel algorithms to explore the efficient solutions. At the circuit level, a new reliability-driven minimum cost Steiner routing and layer assignment scheme is proposed, and the first transceiver insertion algorithmic framework for the optical interconnect is proposed. At the system level, a reliability-driven task scheduling scheme for multiprocessor real-time embedded systems, which optimizes system energy consumption under stochastic fault occurrences, is proposed. The embedded system design is also widely used in the smart home area for improving health, wellbeing and quality …

Design Of Efficient In-Network Data Processing And Dissemination For Vanets, Congyi Liu

Dissertations, Master's Theses and Master's Reports - Open

By providing vehicle-to-vehicle and vehicle-to-infrastructure wireless communications, vehicular ad hoc networks (VANETs), also known as the “networks on wheels”, can greatly enhance traffic safety, traffic efficiency and driving experience for intelligent transportation system (ITS). However, the unique features of VANETs, such as high mobility and uneven distribution of vehicular nodes, impose critical challenges of high efficiency and reliability for the implementation of VANETs. This dissertation is motivated by the great application potentials of VANETs in the design of efficient in-network data processing and dissemination. Considering the significance of message aggregation, data dissemination and data collection, this dissertation research targets at …

Multimodal Performance And Reliability Analysis Of The Pierre Auger Observatory North Site, Maira Maskevics

Dissertations, Master's Theses and Master's Reports - Open

The Pierre Auger Cosmic Ray Observatory North site employs a large array of surface detector stations (tanks) to detect the secondary particle showers generated by ultra-high energy cosmic rays. Due to the rare nature of ultra-high energy cosmic rays, it is important to have a high reliability on tank communications, ensuring no valuable data is lost. The Auger North site employs a peer-to-peer paradigm, the Wireless Architecture for Hard Real-Time Embedded Networks (WAHREN), designed specifically for highly reliable message delivery over fixed networks, under hard real-time deadlines.

The WAHREN design included two retransmission protocols, Micro- and Macro- retransmission. To fully …

Adaptive Sampling With Mobile Sensor Networks, Shuo Huang

Dissertations, Master's Theses and Master's Reports - Open

Mobile sensor networks have unique advantages compared with wireless sensor networks. The mobility enables mobile sensors to flexibly reconfigure themselves to meet sensing requirements. In this dissertation, an adaptive sampling method for mobile sensor networks is presented. Based on the consideration of sensing resource constraints, computing abilities, and onboard energy limitations, the adaptive sampling method follows a down sampling scheme, which could reduce the total number of measurements, and lower sampling cost. Compressive sensing is a recently developed down sampling method, using a small number of randomly distributed measurements for signal reconstruction. However, original signals cannot be reconstructed using condensed …

Automatic Food Intake Assessment Using Camera Phones, Fanyu Kong

Dissertations, Master's Theses and Master's Reports - Open

Obesity is becoming an epidemic phenomenon in most developed countries. The fundamental cause of obesity and overweight is an energy imbalance between calories consumed and calories expended. It is essential to monitor everyday food intake for obesity prevention and management. Existing dietary assessment methods usually require manually recording and recall of food types and portions. Accuracy of the results largely relies on many uncertain factors such as user's memory, food knowledge, and portion estimations. As a result, the accuracy is often compromised. Accurate and convenient dietary assessment methods are still blank and needed in both population and research societies.

In …

Decision Strategies For A P2p Computing System, Grzegorz Chmaj, Krzysztof Walkowiak

Electrical & Computer Engineering Faculty Research

Peer-to-Peer (P2P) computing (also called ‘public-resource computing’) is an effective approach to perform computation of large tasks. Currently used P2P computing systems (e.g., BOINC) are most often centrally managed, i.e., the final result of computations is created at a central node using partial results – what may be not efficient in the case when numerous participants are willing to download the final result. In this paper, we propose a novel approach to P2P computing systems. We assume that results can be delivered to all peers in a distributed way using three types of network flows: unicast, Peer-to-Peer and anycast. We …

Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay

Turkish Journal of Electrical Engineering and Computer Sciences

Hash functions are one of the ubiquitous cryptographic functions used widely for various applications such as digital signatures, data integrity, authentication protocols, MAC algorithms, RNGs, etc. Hash functions are supposed to be one-way, i.e., preimage resistant. One interesting property of hash functions is that they process arbitrary-length messages into fixed-length outputs. In general, this can be achieved mostly by applying compression functions onto the message blocks of fixed length, recursively. The length of the message is incorporated as padding in the last block prior to the hash, a procedure called the Merkle-Damgard strengthening. In this paper, we introduce a new …

A Robust Adaptive Fuzzy Control Of A Unified Power Flow Controller, Sebaa Morsli, Allaoui Tayeb, Denai Mouloud, Chaker Abdelkader

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the control of a unified power flow controller (UPFC) to improve the stability of a power system, hence providing security under increased power flow conditions. The proposed control methods include a direct proportional and integral (PI) controller and an adaptive fuzzy logic controller (AFLC). The performances of these controllers were evaluated under different operating conditions of the power system and the results demonstrated that PI and AFLC are very effective in improving the transient power system stability and very robust against variable transmission line parameters.

Mathematical Modeling And Vertical Flight Control Of A Tilt-Wing Uav, Kaan Taha Öner, Ertuğrul Çeti̇nsoy, Efe Sirimoğlu, Cevdet Hançer, Mustafa Ünel, Mahmut Faruk Akşi̇t, Kayhan Gülez, İlyas Kandemi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a mathematical model and vertical flight control algorithms for a new tilt-wing unmanned aerial vehicle (UAV). The vehicle is capable of vertical take-off and landing (VTOL). Due to its tilt-wing structure, it can also fly horizontally. The mathematical model of the vehicle is obtained using Newton-Euler formulation. A gravity compensated PID controller is designed for altitude control, and three PID controllers are designed for attitude stabilization of the vehicle. Performances of these controllers are found to be quite satisfactory as demonstrated by indoor and outdoor flight experiments.