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Full-Text Articles in Engineering

Open Source Software In Health Information Systems: Opportunities And Challenges, Hashim Twaakyondo Jun 2008

Open Source Software In Health Information Systems: Opportunities And Challenges, Hashim Twaakyondo

Tanzania Journal of Engineering and Technology (TJET)

The paper presents results of a study seeking to identify constraining and motivating factors associated with the adoption and use of Free Open Source Software to computerise health Information Systems in a developing country. The study approach is interpretive research to case study with a triangulation of several qualitative data collection methods such as interviews, group discussions and document analysis. The findings indicate that using open source software has advantages and disadvantages. The advantages are low entry cost to adopting software, possibilities of software localization, avoiding being hostage of proprietary software and foster knowledge acquisition among software developers. The disadvantages …


Clustering Of High-Dimensional Gene Expression Data With Feature Filtering Methods And Diffusion Maps, Rui Xu, Steven Damelin, Boaz Nadler, Donald C. Wunsch May 2008

Clustering Of High-Dimensional Gene Expression Data With Feature Filtering Methods And Diffusion Maps, Rui Xu, Steven Damelin, Boaz Nadler, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The importance of gene expression data in cancer diagnosis and treatment by now has been widely recognized by cancer researchers in recent years. However, one of the major challenges in the computational analysis of such data is the curse of dimensionality, due to the overwhelming number of measures of gene expression levels versus the small number of samples. Here, we use a two-step method to reduce the dimension of gene expression data. At first, we extract a subset of genes based on the statistical characteristics of their corresponding gene expression measurements. For further dimensionality reduction, we then apply diffusion maps, …


Dual-Function Neuron-Based External Controller For A Static Var Compensator, Ganesh K. Venayagamoorthy, Sandhya R. Jetti Apr 2008

Dual-Function Neuron-Based External Controller For A Static Var Compensator, Ganesh K. Venayagamoorthy, Sandhya R. Jetti

Electrical and Computer Engineering Faculty Research & Creative Works

The use of wide-area measurements for power system stabilization has recently been given a lot of attention by researchers and the power industry to avoid cascading failures and blackouts, such as the one in North America in August 2003. This paper presents the design of a nonlinear external damping controller based on wide-area measurements as inputs to a single dual-function neuron (DFN)-based controller. This DFN controller is specifically designed to enhance the damping characteristics of a power system over a wide range of operating conditions using an existing static var compensator (SVC) installation. The major advantage of the DFN controller …


Fault-Tolerant Optimal Neurocontrol For A Static Synchronous Series Compensator Connected To A Power Network, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy Feb 2008

Fault-Tolerant Optimal Neurocontrol For A Static Synchronous Series Compensator Connected To A Power Network, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel fault-tolerant optimal neurocontrol scheme (FTONC) for a static synchronous series compensator (SSSC) connected to a multimachine benchmark power system. The dual heuristic programming technique and radial basis function neural networks are used to design a nonlinear optimal neurocontroller (NONC) for the external control of the SSSC. Compared to the conventional external linear controller, the NONC improves the damping performance of the SSSC. The internal control of the SSSC is achieved by a conventional linear controller. A sensor evaluation and (missing sensor) restoration scheme (SERS) is designed by using the autoassociative neural networks and particle swarm …


Analysis Of Information Remaining On Hand Held Devices Offered For Sale On The Second Hand, Andy Jones, Craig Valli, Iain Sutherland Jan 2008

Analysis Of Information Remaining On Hand Held Devices Offered For Sale On The Second Hand, Andy Jones, Craig Valli, Iain Sutherland

Journal of Digital Forensics, Security and Law

The ownership and use of mobile phones, Personal Digital Assistants and other hand held devices is now ubiquitous both for home and business use. The majority of these devices have a high initial cost, a relatively short period before they become obsolescent and a relatively low second hand value. As a result of this, when the devices are replaced, there are indications that they tend to be discarded. As technology has continued to develop, it has led to an increasing diversity in the number and type of devices that are available, and the processing power and the storage capacity of …


Data Security Measures In The It Service Industry: A Balance Between Knowledge & Action, N. Mlitwa, Y. Kachala Jan 2008

Data Security Measures In The It Service Industry: A Balance Between Knowledge & Action, N. Mlitwa, Y. Kachala

Journal of Digital Forensics, Security and Law

That “knowledge is power” is fast becoming a cliché within the intelligentsia. Such power however, depends largely on how knowledge itself is exchanged and used, which says a lot about the tools of its transmission, exchange, and storage. Information and communication technology (ICT) plays a significant role in this respect. As a networked tool, it enables efficient exchanges of video, audio and text data beyond geographical and time constraints. Since this data is exchanged over the worldwide web (www), it can be accessible by anyone in the world using the internet. The risk of unauthorised access, interception, modification, or even …


Investigation Of Millimetre Wave Generation By Stimulated Brillouin Scattering For Radio Over Fibre Applications, Markus Junker Jan 2008

Investigation Of Millimetre Wave Generation By Stimulated Brillouin Scattering For Radio Over Fibre Applications, Markus Junker

Doctoral

The rising demand for greater bandwidth and increased flexibility in modern telecommunication systems has lead to increased research activities in the field of Millimetre Wave-Photonics. The combination of an optical access network and the radio propagation of high data-rate signals provides a solution to meet these demands. Such structures are also known as Radio Over Fibre Systems. They implement the optical Millimetre Wave generation in a central station and the transmission of radio waves via a remote antenna unit to the radio cell. The expected data rate is very high, due to the fact that both the optical and the …


Real-Time Implementation Of A Statcom On A Wind Farm Equipped With Doubly Fed Induction Generators, Wei Qiao, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2008

Real-Time Implementation Of A Statcom On A Wind Farm Equipped With Doubly Fed Induction Generators, Wei Qiao, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Voltage stability is a key issue to achieve the uninterrupted operation of wind farms equipped with doubly fed induction generators (DFIGs) during grid faults. This paper investigates the application of a static synchronous compensator (STATCOM) to assist with the uninterrupted operation of a wind turbine driving a DFIG, which is connected to a power network, during grid faults. The control schemes of the DFIG rotor- and grid-side converters and the STATCOM are suitably designed and coordinated. The system is implemented in real-time on a real time digital simulator. Results show that the STATCOM improves the transient voltage stability and therefore …


Object Detection And Classification With Applications To Skin Cancer Screening, Jonathan Blackledge, Dmitryi Dubovitskiy Jan 2008

Object Detection And Classification With Applications To Skin Cancer Screening, Jonathan Blackledge, Dmitryi Dubovitskiy

Articles

This paper discusses a new approach to the processes of object detection, recognition and classification in a digital image. The classification method is based on the application of a set of features which include fractal parameters such as the Lacunarity and Fractal Dimension. Thus, the approach used, incorporates the characterisation of an object in terms of its texture.

The principal issues associated with object recognition are presented which includes two novel fast segmentation algorithms for which C++ code is provided. The self-learning procedure for designing a decision making engine using fuzzy logic and membership function theory is also presented and …


Identification Of Induction Machines Stator Currents With Generalized Neurons, Jing Huang, Ganesh K. Venayagamoorthy, Keith Corzine Jul 2007

Identification Of Induction Machines Stator Currents With Generalized Neurons, Jing Huang, Ganesh K. Venayagamoorthy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

A new approach to identify the nonlinear model of an induction machine using two generalized neurons (GNs) is presented in this paper. Compared to the multilayer perceptron feedforward neural network, a GN has simpler structure and lesser requirement in terms of memory storage which is makes it attractive for hardware implementation. This method shows that with less number of weights, GN is able to learn the dynamics of an induction machine. The proposed model is made by two coupled networks. A modified particle swarm optimization algorithm is designed to solve this distinctive GN training problem. A pseudo-random binary sequence signal …


Intelligent Local And Hierarchical Control Of Facts Devices, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Jul 2007

Intelligent Local And Hierarchical Control Of Facts Devices, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an overview of the applications of intelligent control techniques on local and hierarchical control of FACTS devices. These control techniques are superior to the conventional linear/nonlinear control schemes in the sense that they are independent of any mathematical model of the power system to be controlled. In addition, they do not depend on the operating conditions and the configuration of the system to which the FACTS device is connected. A static compensator (STATCOM) is used as the example in order to compare the performances of the proposed intelligent controllers with those of their linear counterparts. Nevertheless, the …


Interdisciplinary Team Teaching: Lessons For Engineering Instructors From A Capstone Course In Environmental Studies, David Braun, Emmit B. Evans, Randall Knight, Thomas Ruehr Jun 2007

Interdisciplinary Team Teaching: Lessons For Engineering Instructors From A Capstone Course In Environmental Studies, David Braun, Emmit B. Evans, Randall Knight, Thomas Ruehr

Electrical Engineering

The capstone course teaches students to analyze global environmental issues, resources, and human activities with a systems approach based on scientific, economic, political, social and ethical perspectives. Such an intrinsically multifaceted subject demands interdisciplinary treatment. To deliver the interdisciplinary treatment, the course uses diverse faculty teams comprised of faculty from fields in the natural and social sciences, engineering, and business. This work describes the interdisciplinary team teaching strategies adopted for the course and how they evolved with subsequent offerings of the course. We present assessment data measuring how well students achieve course objectives. Finally, experience gleaned from this course for …


Swarm Intelligence For Transmission System Control, Ganesh K. Venayagamoorthy, Ronald G. Harley Jun 2007

Swarm Intelligence For Transmission System Control, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Many areas related to power system transmission require solving one or more nonlinear optimization problems. While analytical methods might suffer from slow convergence and the curse of dimensionality, heuristics based swarm intelligence can be an efficient alternative. This paper highlights the application of swam intelligence techniques for solving some of the transmission system control problems.


Dynamic Modeling Of Wind Farms With Fixed-Speed Wind Turbine Generators, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy Jun 2007

Dynamic Modeling Of Wind Farms With Fixed-Speed Wind Turbine Generators, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

A wind farm typically consists of a large number of individual wind turbine generators (WTGs) connected by an internal electrical network. To study the impact of wind farms on the dynamics of the power system, an important issue is to develop appropriate wind farm models to represent the dynamics of many individual WTGs. This paper presents various dynamic models, including a detailed model and three reduced-order equivalent models, of wind farms with fixed-speed WTGs. These models are developed and compared by simulation studies in the PSCAD/EMTDC environment under different wind velocity and fluctuation conditions as well as gird fault conditions. …


Investigating Information Structure Of Phishing Emails Based On Persuasive Communication Perspective, Ki Jung Lee, Il-Yeol Song Apr 2007

Investigating Information Structure Of Phishing Emails Based On Persuasive Communication Perspective, Ki Jung Lee, Il-Yeol Song

Annual ADFSL Conference on Digital Forensics, Security and Law

Current approaches of phishing filters depend on classifying messages based on textually discernable features such as IP-based URLs or domain names as those features that can be easily extracted from a given phishing message. However, in the same sense, those easily perceptible features can be easily manipulated by sophisticated phishers. Therefore, it is important that universal patterns of phishing messages should be identified for feature extraction to serve as a basis for text classification. In this paper, we demonstrate that user perception regarding phishing message can be identified in central and peripheral routes of information processing. We also present a …


Monitoring And Surveillance In The Workplace: Lessons Learnt? – Investigating The International Legal Position, Verine Etsebeth Apr 2007

Monitoring And Surveillance In The Workplace: Lessons Learnt? – Investigating The International Legal Position, Verine Etsebeth

Annual ADFSL Conference on Digital Forensics, Security and Law

When considering the legal implications of monitoring and surveillance in the workplace, the question may be asked why companies deploy computer surveillance and monitoring in the first place. Several reasons may be put forward to justify why more than 80% of all major American firms monitor employee e-mails and Internet usage. However, what most companies forget is the fact that the absence or presence of monitoring and surveillance activities in a company holds serious legal consequences for companies. From the discussion in this paper it will become apparent that there is a vast difference in how most countries approach this …


The Evolution Of Internet Legal Regulation In Addressing Crime And Terrorism, Murdoch Watney Apr 2007

The Evolution Of Internet Legal Regulation In Addressing Crime And Terrorism, Murdoch Watney

Annual ADFSL Conference on Digital Forensics, Security and Law

Internet regulation has evolved from self-regulation to the criminalization of conduct to state control of information available, accessed and submitted. Criticism has been leveled at the different forms of state control and the methods employed to enforce state control. After the terrorist attack on the USA on 11 September 2001, governments justify Internet state control as a law enforcement and national security tool against the abuse and misuse of the Internet for the commission of serious crimes, such as phishing, child pornography; terrorism and copyright infringement. Some Internet users and civil rights groups perceive state control as an abomination which …


Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan Mar 2007

Selecting Electricity Generation Sources In Remote Locations, Kelly E. Kwan

Theses and Dissertations

The purpose of this research was to investigate the impact of using a decision analysis technique for the selection of an electrical generation system for remote locations. Specifically, this thesis sought to answer five research questions addressing the types of energy sources used in remote locations, the decision-making processes used to identify these sources, the types of constraints incorporated in such a process, other valued factors, and their level of importance in relation to each other. The research questions were answered through a comprehensive literature review and the 10-Step Value-Focused Thinking Process on a specific case study in the National …


Threshold Power Of Canonical Antennas For Inducing Sar At Compliance Limits In The 300-3000 Mhz Frequency Range, Mohammod Ali, Mark G. Douglas, Abu T.M. Sayem, Antonio Faraone, Chung-Kwang Chou Feb 2007

Threshold Power Of Canonical Antennas For Inducing Sar At Compliance Limits In The 300-3000 Mhz Frequency Range, Mohammod Ali, Mark G. Douglas, Abu T.M. Sayem, Antonio Faraone, Chung-Kwang Chou

Faculty Publications

A study of the specific absorption rate (SAR) in an exposed body induced by canonical antennas is presented, with the aim of determining an upper bound for the antenna transmit power that demonstrates that a product is inherently compliant with internationally accepted radio frequency (RF) exposure limits. Starting from the fundamental limits in antenna quality factor (Q) and the corresponding bandwidth, several antenna sizes are selected, and their SAR distributions are computed using the method of moments (MoM) and finite-difference time domain (FDTD) method in the frequency range 300-3000 MHz. The threshold powers are then determined, below which the peak …


Modelling And Computer Simulation Of Radarscreening Using Plasma Clouds, Jonathan Blackledge Jan 2007

Modelling And Computer Simulation Of Radarscreening Using Plasma Clouds, Jonathan Blackledge

Conference papers

Following a brief introduction on the principles of screening an aerospace vehicle using a plasma, we develop models for the Impulse Response Functions (IRFs) associated with microwave (Radar) back-scattering from a strong and weakly ionized plasma screen. For a weakly ionized plasma, the conductivity is determined by the number density of electrons. We develop a model for an electron beam induced plasma that includes the effect of cascade ionization and losses due to diffusion and recombination. Qualitative results are then derived for the number density of a plasma screen over a sub-sonic aerospace vehicle and a numerical simulation considered that …


A Critical Review On Electromagnetic Precursors And Earthquake Prediction, Levent Sevgi̇ Jan 2007

A Critical Review On Electromagnetic Precursors And Earthquake Prediction, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Seismo-electromagnetic precursory-based earthquake prediction studies are criticized in terms of their scientific content, problem complexity, signal excitation and propagation, causal relations with earthquakes, and public awareness and expectations. One aim is to trigger a new debate on this hot topic in the Electromagnetic Society.


Monitoring And Surveillance In The Workplace: Lessons Learnt? – Investigating The International Legal Position, Verine Etsebeth Jan 2007

Monitoring And Surveillance In The Workplace: Lessons Learnt? – Investigating The International Legal Position, Verine Etsebeth

Journal of Digital Forensics, Security and Law

When considering the legal implications of monitoring and surveillance in the workplace, the question may be asked why companies deploy computer surveillance and monitoring in the first place. Several reasons may be put forward to justify why more than 80% of all major American firms monitor employee e-mails and Internet usage. However, what most companies forget is the fact that the absence or presence of monitoring and surveillance activities in a company holds serious legal consequences for companies. From the discussion in this paper it will become apparent that there is a vast difference in how most countries approach this …


The Evolution Of Internet Legal Regulation In Addressing Crime And Terrorism, Murdoch Watney Jan 2007

The Evolution Of Internet Legal Regulation In Addressing Crime And Terrorism, Murdoch Watney

Journal of Digital Forensics, Security and Law

Internet regulation has evolved from self-regulation to the criminalization of conduct to state control of information available, accessed and submitted. Criticism has been leveled at the different forms of state control and the methods employed to enforce state control. After the terrorist attack on the USA on 11 September 2001, governments justify Internet state control as a law enforcement and national security tool against the abuse and misuse of the Internet for the commission of serious crimes, such as phishing, child pornography; terrorism and copyright infringement. Some Internet users and civil rights groups perceive state control as an abomination which …


Investigating Information Structure Of Phishing Emails Based On Persuasive Communication Perspective, Ki J. Lee, Il-Yeol Song Jan 2007

Investigating Information Structure Of Phishing Emails Based On Persuasive Communication Perspective, Ki J. Lee, Il-Yeol Song

Journal of Digital Forensics, Security and Law

Current approaches of phishing filters depend on classifying messages based on textually discernable features such as IP-based URLs or domain names as those features that can be easily extracted from a given phishing message. However, in the same sense, those easily perceptible features can be easily manipulated by sophisticated phishers. Therefore, it is important that universal patterns of phishing messages should be identified for feature extraction to serve as a basis for text classification. In this paper, we demonstrate that user perception regarding phishing message can be identified in central and peripheral routes of information processing. We also present a …


Development Of An Intelligent Autonomous Coffee Maker, Nicholas J. Vanderpool Jan 2007

Development Of An Intelligent Autonomous Coffee Maker, Nicholas J. Vanderpool

Browse all Theses and Dissertations

Using Intelligent Control Methodology Home coffee machines have improved over time with the addition of features such as self-activating timers and crude temperature controlled heating elements. However, home coffee brewer development has stagnated and has yet to achieve full automation status. Present coffee machines leave the user burdened with the mundane and messy task of preparing the coffee maker every time. Also, should the user decide to prepare less than an entire pot, he/she must estimate the correct amount of water and coffee to add. This can lead to a weak or strong brew, giving undesirable results. In order to …


Optimal Neuro-Fuzzy External Controller For A Statcom In The 12-Bus Benchmark Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2007

Optimal Neuro-Fuzzy External Controller For A Statcom In The 12-Bus Benchmark Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal neuro-fuzzy external controller is designed in this paper for a static compensator (STATCOM) in the 12-bus benchmark power system. The controller provides an auxiliary reference signal for the STATCOM in such a way that it improves the damping of the rotor speed deviations of its neighboring generators. A Mamdani fuzzy rule base constitutes the core of the controller. A heuristic dynamic programming-based approach is used to further train the controller and enable it to provide nonlinear optimal control at different operating conditions of the power system. Simulation results are provided that indicate the proposed neuro-fuzzy external controller is …


Comparison Of Nonuniform Optimal Quantizer Designs For Speech Coding With Adaptive Critics And Particle Swarm, Ganesh K. Venayagamoorthy, Wenwei Zha Jan 2007

Comparison Of Nonuniform Optimal Quantizer Designs For Speech Coding With Adaptive Critics And Particle Swarm, Ganesh K. Venayagamoorthy, Wenwei Zha

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design of a companding nonuniform optimal scalar quantizer for speech coding. The quantizer is designed using two neural networks to perform the nonlinear transformation. These neural networks are used in the front and back ends of a uniform quantizer. Two approaches are presented in this paper namely adaptive critic designs and particle swarm optimization, aiming to maximize the signal-to-noise ratio. The comparison of these optimal quantizer designs over a bit-rate range of 3-6 is presented. The perceptual quality of the coding is evaluated by the International Telecommunication Union's Perceptual Evaluation of Speech Quality standard


A Proportional-Integrator Type Adaptive Critic Design-Based Neurocontroller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Yamille Del Valle, Ronald G. Harley Jan 2007

A Proportional-Integrator Type Adaptive Critic Design-Based Neurocontroller For A Static Compensator In A Multimachine Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Yamille Del Valle, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

A novel nonlinear optimal controller for a static compensator (STATCOM) connected to a power system, using artificial neural networks, is presented in this paper. The action dependent heuristic dynamic programming, a member of the adaptive critic designs family is used for the design of the STATCOM neurocontroller. This neurocontroller provides optimal control based on reinforcement learning and approximate dynamic programming. Using a proportional-integrator approach, the proposed neurocontroller is capable of dealing with actual rather than deviation signals. Simulation results are provided to show that the proposed controller outperforms a conventional PI controller for a STATCOM in a small and large …


Neural Network Based Method For Predicting Nonlinear Load Harmonics, Joy Mazumdar, Ronald G. Harley, Frank C. Lambert, Ganesh K. Venayagamoorthy Jan 2007

Neural Network Based Method For Predicting Nonlinear Load Harmonics, Joy Mazumdar, Ronald G. Harley, Frank C. Lambert, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Generation of harmonics and the existence of waveform pollution in power system networks are important problems facing the power utilities. The increased use of nonlinear devices in industry has resulted in direct increase of harmonic distortion in the industrial power system in recent years. Interaction between loads and sources in a power distribution network is a complex process and often not possible to explain analytically without making assumptions. The determination of true harmonic current distortion of a load is further complicated by the fact that the supply voltage waveform at the point of common coupling (PCC) is rarely a pure …


Optimal Wide Area Controller And State Predictor For A Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2007

Optimal Wide Area Controller And State Predictor For A Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal wide area controller is designed in this paper for a 12-bus power system together with a Static Compensator (STATCOM). The controller provides auxiliary reference signals for the automatic voltage regulators (AVR) of the generators as well as the line voltage controller of the STATCOM in such a way that it improves the damping of the rotor speed deviations of the synchronous machines. Adaptive critic designs theory is used to implement the controller and enable it to provide nonlinear optimal control over the infinite horizon time of the problem and at different operating conditions of the power system. Simulation …