Engineering Commons^™

Distributed Spectrum Leasing Via Cooperation, Tariq Elkourdi

Dissertations

“Cognitive radio” networks enable the coexistence of primary (licensed) and secondary (unlicensed) terminals. Conventional frameworks, namely commons and property-rights models, while being promising in certain aspects, appear to have significant drawbacks for implementation of large-scale distributed cognitive radio networks, due to the technological and theoretical limits on the ability of secondary activity to perform effective spectrum sensing and on the stringent constraints on protocols and architectures.

To address the problems highlighted above, the framework of distributed spectrum leasing via cross-layer cooperation (DiSC) has been recently proposed as a basic mechanism to guide the design of decentralized cognitive radio networks. According …

Distributed Solar Photovoltaic Grid Integration System : A Case Study For Performance, Ming Shen

Dissertations and Theses

The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems come with increasing DG penetration in distribution networks. This thesis presents the Solar Energy Grid Integration System (SEGIS) Stage III project done by Portland General Electric (PGE), Advanced Energy, Sandia National Lab on a PGE selected distribution feeder. The feeder has six monitored commercial solar PV systems connected. The total power output from the PV systems has the potential to reach 30% of the feeder load. The author analyzes the performance of the solar …

Commentary And Interpretations Of Tagore’S 'Ode To Africa', Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

This is a commentary/interpretation of Rabindranath Tagore's poem "Ode to Africa."

Maximum Power Point Tracking Control Of Hydrokinetic Turbine And Low-Speed High-Thrust Permanent Magnet Generator Design, Hailong Zhou

Masters Theses

"River-based hydrokinetic turbine power generation systems have been studied to introduce an effective energy flow control method. Hydrokinetic turbine systems share a lot of similarities with wind turbine systems in terms of physical principles of operation, electrical hardware, and variable speed capability for optimal energy extraction. A multipole permanent magnet synchronous generator is used to generate electric power because of its ability to reach high power density and high thrust at low speed. A 3-phase diode rectifier is used to convert AC power from the generator into DC power and a boost converter is used to implement energy flow control. …

Engineering Evaluation Of Multi-Beam Satellite Antenna Boresight Pointing Using Land/Water Crossings, Catherine Susan May

Electronic Theses and Dissertations

The Microwave Radiometer (MWR) on the Aquarius/SAC-D mission measures microwave radiation from earth and intervening atmosphere in terms of brightness temperature (Tb). It takes measurements in a push-broom fashion at K (23.8GHz) and Ka (36.5 GHz) band frequencies using two separate antenna systems, each producing eight antenna beams. Pre-launch knowledge of the alignment of these beams with respect to the space-craft is used to geolocate the antenna footprints on ground. As a part of MWR’s on-orbit engineering check-out, the verification of MWR’s pointing accuracy is discussed here. The technique used to assess MWR’s pointing involved comparing the radiometer image of …

A Pseudo Spot Price Of Electricity Algorithm Applied To Environmental Economic Active Power Dispatch Problem, Celal Yaşar

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an environmental economic active power dispatch problem is transformed into an optimization problem with a single-objective function by applying the weighted sum method (WSM) and the conic scalarization method (CSM). A pseudo spot price of electricity algorithm (PSPA) is used to solve the transformed problem. This is demonstrated on an example problem, which is a lossy electrical power system having only thermal units The WSM and CSM methods are applied to the example problem, and the weight factor values of these methods is increased from 0 to 1 by a step size of 0.1. For each possible …

Identification Of Starry Milia-Like Cysts In Seborrheic Keratoses And Malignant Melanomas Using Image Processing Techniques, Viswanaath Subramanian

Masters Theses

"Seborrheic keratoses are the most common benign tumors found in older individuals. Seborrheic keratoses are normally benign in nature, but sometimes in a large lesion area of seborrheic keratoses, secondary tumors, or squamous cell carcinoma in situ or malignant melanoma may occur. It has been found that seborrheic keratoses have a few features that distinguish them from melanomas. Milia-like cysts, comedo-like openings and network-like structures are the most prominent features found in seborrheic keratoses. Comedo-like openings are pigmented structures and are mostly oval yellowish, brown or black in appearance. They can also be observed in melanocytic lesions and melanomas. Milia-like …

Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney

Articles

Medical imaging is a fertile area for computer graphics, image processing and real time visualization. In this paper we present a method for reducing noise in CT (Computed Tomography) and MR (Magnetic Resonance) images that (in addition to other noise sources) is characteristic of the numerical procedures required to construct the images, namely, the (inverse) Radon Transform. In both cases, MR imaging in particular, an additional noise source is due to the process of diffusion thereby predicating use of the Anisotropic Diffusion method for noise suppression. This method is based on a diffusion model for noise generation where the Diffusivity …

Magnetic Cell Separation By Inkjet Printing For Disease Monitoring, Sylvia Lucia Natividad

Open Access Theses & Dissertations

The standard analysis technique for cell sorting, flow cytometry, requires centralized facilities such as tertiary Medical Centers. According to the U.S. Department of Health and Human Services Designated Health Professional Shortage Areas (HPSA) Statistics, in this country alone, more than 35 million people live in medically underserved areas, many of which need access to diagnostic procedures for proper management of their diseases. A cell sorting technique that can be done in low-resource settings at a decreased cost to the medical organization and the patient has been developed through this research project. By combining inkjet printing technology and magnetic labeling of …

On-Line Voltage Stability Load Index Estimation Based On Pmu Measurements, K. Joseph Makasa, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

A new method for estimation of Voltage Stability Load Index (VSLI) for a power system using data from optimally located phasor measurement units (PMU) is presented in this paper. Optimal PMU placement was carried out considering islanding operating conditions. vs.LI is estimated using a kind of recurrent neural network known as the Echo State Network (ESN). the development ESN is computational efficient and provides accurate estimation. Results of optimal PMU placement for normal and islanded operating conditions, and ESN estimation of vs.LI on the IEEE 14 bus system is presented. © 2011 IEEE.

Innovative Smart Grid Control Technologies, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The smart electric power grid will evolve into a very complex adaptive system under semi-autonomous distributed control. It will be spatially and temporally complex, non-convex, non-linear and non-stationary, with lots of variability and uncertainties beyond what the traditional power system experiences today. the distributed integration of intermittent sources of energy and energy storage to a power grid further adds complexity and challenges to modeling, control and optimization of the grid. Innovative control technologies are needed to handle the growing complexity of a smart grid, maximize the penetration of renewable energy, and provide maximum utilization of available energy storage, especially plug-in …

Intelligent Sense-Making For Smart Grid Stability, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

The power systems of the future - smart grids - will see an increase in both renewable energy sources and load demand, thus increasing the need for fast dynamic reconfiguration of system parameters to handle energy and load dispatches. Power systems will need to be monitored continuously to maintain stability under normal and abnormal operating conditions and when facing disturbances. a combination of system state prediction, dynamic power flow, system optimization, and solution stability checking will allow for a more reliable, affordable, efficient and clean power grid. the optimization and control systems on a smart grid will require a computational …

Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper summarizes past and ongoing research in the area of the application of computational intelligence (CI) for control of wind turbine generators (WTGs). Several intelligent design approaches and control strategies, including optimal design of WTG controllers using particle swarm optimization (PSO) and mean-variance optimization (MVO) algorithms and adaptive critic design-Based coordinated optimal adaptive control for wind plants and shunt FACTS devices, are presented for dynamic performance and fault ride-through enhancement of WTGs and the associated power grid. the effectiveness of these intelligent design approaches and control strategies are demonstrated by nonreal- and real-time simulations in PSCAD/EMTDC and RSCAD/RTDS, respectively. …

Linear Precoding For Mimo Multiple Access Channels With Discrete-Constellation Inputs, Mingxi Wang, Weiliang Zeng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we study linear precoding for multiple-input multiple-output (MIMO) multiple access channels (MAC) with discrete-constellation inputs. We derive the constellation-constrained capacity region for the MIMO MAC with an arbitrary number of users. Due to the non-concavity of the objective function, we obtain the necessary conditions for the weighted sum rate (WSR) maximization problem through Karush-Kuhn-Tucker (KKT) analysis. to find the optimal precoding matrices, we propose an iterative algorithm utilizing alternating optimization strategy and gradient descent update. Numerical results show that when inputs are digital modulated signals and the signal-to-noise ratio (SNR) is in the medium range, our proposed …

Smartpark As A Virtual Statcom, Pinaki Mitra, Ganesh K. Venayagamoorthy, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Power electronic-Based FACTS devices such as STATCOMs are sometimes essential for voltage support in transmission networks. They can also be used for continuous operation of doubly fed induction generator-Based wind turbines during faults. However, these devices are quite expensive and therefore cannot be used extensively. This paper explores the potential of a low-cost solution that utilizes the reactive power and voltage support capabilities of plug-in vehicles parked in charging stations (SmartParks) so that they can behave as virtual STATCOMs. for this solution, a 12-bus multimachine power system is considered wherein one of the conventional units is replaced by a 400 …

Development Of An Experimental Phased-Array Feed System And Algorithms For Radio Astronomy, Jonathan Charles Landon

Theses and Dissertations

Phased array feeds (PAFs) are a promising new technology for astronomical radio telescopes. While PAFs have been used in other fields, the demanding sensitivity and calibration requirements in astronomy present unique new challenges. This dissertation presents some of the first astronomical PAF results demonstrating the lowest noise temperature and highest sensitivity at the time (66 Kelvin and 3.3 m^2/K, respectively), obtained using a narrowband (425 kHz bandwidth) prototype array of 19 linear co-polarized L-band dipoles mounted at the focus of the Green Bank 20 Meter Telescope at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. Results include …

Automatic Merging Of Lidar Point-Clouds Using Data From Low-Cost Gps/Imu Systems, Scott E. Budge, K. Von Niederhausern

Electrical and Computer Engineering Faculty Publications

Stationary lidar (Light Detection and Ranging) systems are often used to collect 3-D data (point clouds) that can be used for terrain modelling. The lidar gathers scans which are then merged together to map a terrain. Typically this is done using a variant of the well-known Iterated Closest Point (ICP) algorithm when position and pose of the lidar scanner is not accurately known. One difficulty with the ICP algorithms is that they can give poor results when points that are not common to both scans (outliers) are matched together. With the advent of MEMS (microelectromechanical systems)-based GPS/IMU systems, it is …

Portable Solar Desalination System, Genaro Sanchez, Alan Galarza, Erick Del Real

Electrical Engineering

Clean water and reliable energy can be difficult to obtain in remote locations such as desert villages, secluded islands, and other places where no fresh water can be found. The primary goal for this project is address these problems by implementing a portable desalinization plant system that is to be powered by solar energy PV system as the main energy source.

Optimizing Resource Allocation In Next-Generation Optical Access Networks, Jingjing Zhang

Dissertations

To meet rapidly increasing traffic demands caused by the popularization of Internet and the spouting of bandwidth-demanding applications, Passive Optical Networks (PONs) exploit the potential capacities of optical fibers, and are becoming promising future-proof access network technologies. On the other hand, for a broader coverage area and higher data rate, integrated optical and wireless access is becoming a future trend for wireless access. This thesis investigates three next-generation access networks: Time Division Multiplexing (TDM) PONs, Wavelength Division Multiplexing (WDM) PONs, and WDM Radio-Over-Fiber (RoF) Picocellular networks.

To address resource allocation problems in these three networks, this thesis first investigates respective …

The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati

Makara Journal of Technology

Eucheuma cottonii seaweed is a species of seaweed cultured in Indonesian waters, because its cultivation is relatively easy and inexpensive. It has a wide variety of colors from green to yellow green, gray, red and brown, indicating photosynthetic pigments, such as chlorophyll and carotenoids. An important factor in the effectiveness of pigment extraction is the choice of solvent. The correct type of solvent in the extraction method of specific natural materials is important so that a pigment with optimum quality that is also benefical to the society can be produced. The target of this research is to obtain a high …

Solar Power System Modeling And Performance Analysis, Jiaqi Wang

Electronic Theses and Dissertations

At present the main source of our power and energy needs are from fossil fuel; almost all transportation tools and nearly 70% of electrical power are produced by fossil fuel. But unfortunately these materials are limited in our planet, with obvious drawback such as pollution. So looking for new kinds of energy supply is an urgent matter. Solar-powered photovoltaic system provides a clean energy solution to this problem. It is developing fast all over the world in terms of both research work and actual applications. It is estimated that the power supplied by solar energy can provide 10 percent of …

Performance Analysis Of Mimo-Sess With Alamouti Scheme Over Rayleigh Fading Channels, Shichuan Ma, Lim Nguyen, Yaoqing Lamar Yang, Won Mee Jang

Department of Electrical and Computer Engineering: Faculty Publications

Self-encoded spread spectrum (SESS) is a novel modulation technique that acquires its spreading sequence from the random input data stream rather than through the use of the traditional pseudo-noise code generator. It has been incorporated with multiple-input multiple-output (MIMO) systems as a means to combat fading in wireless channels. In this paper, we present the analytical study of the bit-error rate (BER) performance of MIMO-SESS systems under Rayleigh fading. The BER expressions are derived in closed form, and the veracity of the analysis is confirmed by numerical calculations that demonstrate excellent agreement with simulation results. The performance analysis shows that …

Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu Subandhu Hirlekar

Masters Theses

"Voltage instability has become a growing concern in the operation of power systems in recent years. The reason is that power systems all over are being operated with reduced margins because of increased demand exacerbated by a general reluctance to invest in improvement of the electric grid infrastructure. Until recently it was difficult to predict voltage instability in the on-line environment. However, advances in technology has made possible the on-line monitoring and assessment of voltage stability. Synchrophasors is a relatively new technology in the field of power systems which allows system operators to monitor the system conditions at specific measurement …

Hydro-Electric Generation System For The Dc House Project, Dennis Kwan, Mitchell Krug

Electrical Engineering

This paper focuses on the design, integration, and construction of a system that harnesses energy from flowing water. The system will be used in conjunction with the DC House Project. The proposed system employs a DC generator and DC-DC Boost-converter to provide electricity to the DC House at approximately 200-300W. Results of the testing and measurement show that the goal of the system is feasible, but currently limited. The generator could not output the specified power. Details of the design, along with ideas for further improvement, are presented in this report.

Weak Gradient Inverse Scattering Solutions, Jonathan Blackledge

Conference papers

The paper briefly reviews formal methods and associated conditions for solving the forward and inverse Schrodinger ¨ scattering problem for a three-dimensional elastic scattering potential. These methods are based on an application of the Green’s function and are conditional upon the properties of the scattering potential, e.g. that the scattering potential is a ‘weak scatterer’. In this paper, we explore an alternative route to solving the problem which depends on properties imposed on the scattered wavefield rather than the scattering potential. In particular, we explore the case when the gradient of the scattered wavefield is weak relative to its frequency. …

Impulse Oscillometric Features And Parsimonious Respiratory Models Track Small Airway Function In Hispanic And Anglo Children, Erika Guadalupe Meraz Tena

Open Access Theses & Dissertations

Asthma is an inflammatory condition of the peripheral (small) airways resulting in airway hyper-reactivity and, among other symptoms, airflow obstruction. It is the most prevalent chronic respiratory disease in children. Reliable and patient-friendly instruments and methods are required to help pulmonologists accurately detect asthma and Small Airway Impairment (SAI) with acceptable clinical accuracy, specificity and sensitivity. Impulse Oscillometry System (IOS) based on the Forced Oscillation Technique (FOT) has been successfully used to measure lung function in children with a high degree of sensitivity and specificity to SAI and Asthma. IOS is a patient-friendly lung function to measure the mechanical impedance …

Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle

Articles

— Electricity and the inherent risks associated with its use in the built environment have long since been a priority for the electrical services industry and also the general public who must live and work in this environment. By its nature virtual reality has the advantage of being safe for both the user and equipment. In addition, it offers the user an opportunity to be exposed to a range of scenarios and conditions that either occur infrequently or are hazardous to replicate. This paper presents a prototype desktop virtual reality model, to enhance electrical safety and design in the built …

Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley

Department of Electrical and Computer Engineering: Faculty Publications

This paper summarizes past and ongoing research in the area of the application of computational intelligence (CI) for control of wind turbine generators (WTGs). Several intelligent design approaches and control strategies, including optimal design of WTG controllers using particle swarm optimization (PSO) and mean-variance optimization (MVO) algorithms and adaptive critic design-based coordinated optimal adaptive control for wind plants and shunt FACTS devices, are presented for dynamic performance and fault ride-through enhancement of WTGs and the associated power grid. The effectiveness of these intelligent design approaches and control strategies are demonstrated by nonreal- and real-time simulations in PSCAD/EMTDC and RSCAD/RTDS, respectively.

Secure Relay Beamforming Over Cognitive Radio Channels, Junwei Zhang, Mustafa Cenk Gursoy

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, a cognitive relay channel is considered, and amplify-and-forward (AF) relay beam forming designs in the presence of an eavesdropper and a primary user are studied. Our objective is to optimize the performance of the cognitive relay beamforming system while limiting the interference in the direction of the primary receiver and keeping the transmitted signal secret from the eavesdropper. We show that under both total and individual power constraints, the problem becomes a quasiconvex optimization problem which can be solved by interior point methods. We also propose two sub-optimal null space beamforming schemes which are obtained in a …

Reducing Dimensionality Of Hyperspectral Data With Diffusion Maps And Clustering With K-Means And Fuzzy Art, Louis Du Plessis, Rui Xu, Steven Damelin, Michael Sears, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

It is very difficult to analyse large amounts of hyperspectral data. Here we present a method based on reducing the dimensionality of the data and clustering the result in moving toward classification of the data. Dimensionality reduction is done with diffusion maps, which interpret the eigenfunctions of Markov matrices as a system of coordinates on the original dataset in order to obtain an efficient representation of data geometric descriptions. Clustering is done using k-means and a neural network clustering theory, Fuzzy ART (FA). The process is done on a subset of core data from AngloGold Ashanti, and compared to results …