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Full-Text Articles in Engineering

Homogenous Ensemble Phonotactic Language Recognition Based On Svm Supervector Reconstruction, Wei-Wei Liu, Wei-Qiang Zhang, Michael T. Johnson, Jia Liu Dec 2014

Homogenous Ensemble Phonotactic Language Recognition Based On Svm Supervector Reconstruction, Wei-Wei Liu, Wei-Qiang Zhang, Michael T. Johnson, Jia Liu

Electrical and Computer Engineering Faculty Research and Publications

Currently, acoustic spoken language recognition (SLR) and phonotactic SLR systems are widely used language recognition systems. To achieve better performance, researchers combine multiple subsystems with the results often much better than a single SLR system. Phonotactic SLR subsystems may vary in the acoustic features vectors or include multiple language-specific phone recognizers and different acoustic models. These methods achieve good performance but usually compute at high computational cost. In this paper, a new diversification for phonotactic language recognition systems is proposed using vector space models by support vector machine (SVM) supervector reconstruction (SSR). In this architecture, the subsystems share the same …


A Microfluidic Device For Thermal Particle Detection, Ashwin Kumar Vutha, Benyamin Davaji, Chung-Hoon Lee, Glenn M. Walker Nov 2014

A Microfluidic Device For Thermal Particle Detection, Ashwin Kumar Vutha, Benyamin Davaji, Chung-Hoon Lee, Glenn M. Walker

Electrical and Computer Engineering Faculty Research and Publications

We demonstrate the use of heat to count microscopic particles. A thermal particle detector (TPD) was fabricated by combining a 500-nm-thick silicon nitride membrane containing a thin-film resistive temperature detector with a silicone elastomer microchannel. Particles with diameters of 90 and 200 μm created relative temperature changes of 0.11 and −0.44 K, respectively, as they flowed by the sensor. A first-order lumped thermal model was developed to predict the temperature changes. Multiple particles were counted in series to demonstrate the utility of the TPD as a particle counter.


Thermal Characterization Of Liquid Samples With Three-Dimensional On-Chip Micro Calorimeter, Hye Jeong Bak Oct 2014

Thermal Characterization Of Liquid Samples With Three-Dimensional On-Chip Micro Calorimeter, Hye Jeong Bak

Master's Theses (2009 -)

This thesis presents a three dimensional on-chip microfabricated calorimeter (μ-calorimeter) to extract thermal diffusivity and specific heat capacity of liquid samples. These thermal properties are used to understand thermal reaction behavior, obtain information of stability for reactant molecules, and characterize a material. Thermally characterized solvents can be utilized to investigate a solute. The μ-calorimeter introduced in this work has 3D wafer-scale structure. The μ-calorimeter consists of a reaction chamber, a nickel heater, and a resistance temperature detector (RTD) sensor. The reaction chamber enables analysis of 200 nl liquid samples. Also, its enclosed structure prevents liquid sample evaporation during an experiment. …


A Microsoft Vba Application For Generating Heat Maps, Mark Polczynski, Michael Polczynski Oct 2014

A Microsoft Vba Application For Generating Heat Maps, Mark Polczynski, Michael Polczynski

Electrical and Computer Engineering Faculty Research and Publications

A choropleth map is a form of thematic map used to portray the structural characteristics of some particular geographical distribution not apparent in data presented in tabular form. Preparation of a choropleth map starts with the assignment of map features to classes based on the value of a specific feature attribute followed by the association of classes of features with appropriate map colors or symbols. Map features are often geographical regions with naturally or artificially defined boundaries, but choropleth maps can also be prepared by segmenting the area to be mapped into a regular grid of regions. Maps prepared with …


Speaker Independent Acoustic-To-Articulatory Inversion, An Ji Oct 2014

Speaker Independent Acoustic-To-Articulatory Inversion, An Ji

Dissertations (1934 -)

Acoustic-to-articulatory inversion, the determination of articulatory parameters from acoustic signals, is a difficult but important problem for many speech processing applications, such as automatic speech recognition (ASR) and computer aided pronunciation training (CAPT). In recent years, several approaches have been successfully implemented for speaker dependent models with parallel acoustic and kinematic training data. However, in many practical applications inversion is needed for new speakers for whom no articulatory data is available. In order to address this problem, this dissertation introduces a novel speaker adaptation approach called Parallel Reference Speaker Weighting (PRSW), based on parallel acoustic and articulatory Hidden Markov Models …


Flux-Weakening Control For Permanent-Magnet Synchronous Motors Based On Z-Source Inverters, Muyang Li Oct 2014

Flux-Weakening Control For Permanent-Magnet Synchronous Motors Based On Z-Source Inverters, Muyang Li

Master's Theses (2009 -)

Permanent magnet synchronous machines (PMSMs) have high efficiency, high power density, high torque-to-inertia ratio, and fast dynamic response. These features make this kind of machines very attractive for electric vehicle (EV) applications. However, because of their nature, i.e., constant magnet flux provided by magnets, these machines have a narrow constant power speed range (CPSR). This limitation is a strong drawback for application of PMSMs in electric vehicles, where high speed is the top requirement. Two different approaches can extend the maximum speed under constant power: (1) Increasing a drive's output voltage, and (2) implementing flux-weakening (FW) control methods. However, a …


Surface Acoustic Wave (Saw)-Based Gas Flow Sensor, Nisar Ahmad Oct 2014

Surface Acoustic Wave (Saw)-Based Gas Flow Sensor, Nisar Ahmad

Dissertations (1934 -)

There has been a growing interest in using SAW devices for sensing various physical parameters such as pressure, acceleration, temperature, and gas. The current research has been undertaken to derive a model of a SAW-based gas flow rate sensor, using the principle of heat transfer with the flow of gas. It consists of a SAW delay line fabricated on a suitable substrate and a thin film heater to heat the SAW device to a suitable temperature above the ambient. The delay line is connected in the feedback loop of an rf-amplifier resulting in a delay line stabilized SAW oscillator. When …


A Paper-Based Calorimetric Microfluidics Platform For Bio-Chemical Sensing, Benyamin Davaji, Chung Hoon Lee Sep 2014

A Paper-Based Calorimetric Microfluidics Platform For Bio-Chemical Sensing, Benyamin Davaji, Chung Hoon Lee

Electrical and Computer Engineering Faculty Research and Publications

In this report, a paper-based micro-calorimetric biochemical detection method is presented. Calorimetric detection of biochemical reactions is demonstrated as an extension of current colorimetric and electrochemical detection mechanisms of paper-based biochemical analytical systems. Reaction and/or binding temperature of glucose/glucose oxidase, DNA/hydrogen peroxide, and biotin/streptavidin, are measured by the paper-based micro-calorimeter. Commercially available glucose calibration samples of 0.05, 0.15 and 0.3% wt/vol concentration are used for comparing the device performance with a commercially available glucose meter (electrochemical detection). The calorimetric glucose detection demonstrates a measurement error less than 2%. The calorimetric detection results of DNA concentrations from 0.9 to 7.3 mg/mL …


Application Of Information And Communication Technologies For Historical Research, Michael Polczynski, Mark Polczynski Sep 2014

Application Of Information And Communication Technologies For Historical Research, Michael Polczynski, Mark Polczynski

Electrical and Computer Engineering Faculty Research and Publications

No abstract provided.


Applying Data Mining Tools To Archaeological "Big Data", Michael Polczynski, Mark Polczynski Sep 2014

Applying Data Mining Tools To Archaeological "Big Data", Michael Polczynski, Mark Polczynski

Electrical and Computer Engineering Faculty Research and Publications

No abstract provided.


Multi-Objective Tradeoffs In The Design Optimization Of A Brushless Permanent-Magnet Machine With Fractional-Slot Concentrated Windings, Peng Zhang, Gennadi Y. Sizov, Muyang Li, Dan M. Ionel, Nabeel Demerdash, Steven J. Stretz, Alan W. Yeadon Sep 2014

Multi-Objective Tradeoffs In The Design Optimization Of A Brushless Permanent-Magnet Machine With Fractional-Slot Concentrated Windings, Peng Zhang, Gennadi Y. Sizov, Muyang Li, Dan M. Ionel, Nabeel Demerdash, Steven J. Stretz, Alan W. Yeadon

Electrical and Computer Engineering Faculty Research and Publications

In this paper, a robust parametric model of a brushless permanent magnet machine with fractional-slot concentrated windings, which was developed for automated design optimization is presented. A computationally efficient finite-element analysis method was employed to estimate the dq-axes inductances, the induced voltage and torque ripple waveforms, and losses of the machine. A method for minimum effort calculation of the torque angle corresponding to the maximum torque per ampere load condition was developed. A differential evolution algorithm was implemented for the global design optimization with two concurrent objectives of minimum losses and minimum material cost. An engineering decision process based on …


Generalized Approach Of Stator Shifting In Interior Permanent-Magnet Machines Equipped With Fractional-Slot Concentrated Windings, Patel B. Reddy, Kum-Kang Huh, Ayman M. El-Refaie Sep 2014

Generalized Approach Of Stator Shifting In Interior Permanent-Magnet Machines Equipped With Fractional-Slot Concentrated Windings, Patel B. Reddy, Kum-Kang Huh, Ayman M. El-Refaie

Electrical and Computer Engineering Faculty Research and Publications

Electrical drive systems, which include electrical machines and power electronics, are a key enabling technology for advanced vehicle propulsion systems that reduce the petroleum dependence of the ground transportation sector. To have significant effect, electric drive technologies must be economical in terms of cost, weight, and size while meeting performance and reliability expectations. Interior permanent magnet machines with fractional-slot concentrated windings have been shown to be good candidates for hybrid traction applications. One of the key challenges is the additional stator magnetomotive force sub- and superharmonic components that lead to higher losses in the rotor as well as saturation effects. …


Comparative Assessment Of Diverse Strategies For Malaria Vector Population Control Based On Measured Rates At Which Mosquitoes Utilize Targeted Resource Subsets, Gerry F. Killeen, Samson Sifael Kiware, Aklilu Seyoum, John E. Gimnig, George Corliss, Jennifer Stevenson, Christopher J. Drakeley, Nakul Chitnis Aug 2014

Comparative Assessment Of Diverse Strategies For Malaria Vector Population Control Based On Measured Rates At Which Mosquitoes Utilize Targeted Resource Subsets, Gerry F. Killeen, Samson Sifael Kiware, Aklilu Seyoum, John E. Gimnig, George Corliss, Jennifer Stevenson, Christopher J. Drakeley, Nakul Chitnis

Electrical and Computer Engineering Faculty Research and Publications

Background

Eliminating malaria requires vector control interventions that dramatically reduce adult mosquito population densities and survival rates. Indoor applications of insecticidal nets and sprays are effective against an important minority of mosquito species that rely heavily upon human blood and habitations for survival. However, complementary approaches are needed to tackle a broader diversity of less human-specialized vectors by killing them at other resource targets.

Methods

Impacts of strategies that target insecticides to humans or animals can be rationalized in terms of biological coverage of blood resources, quantified as proportional coverage of all blood resources mosquito vectors utilize. Here, this concept …


Deterministic And Stochastic Resilience Analysis Of Minimum-Time-Controlled Discrete-Time Systems, Jennifer L. Bonniwell, Susan C. Schneider Phd, Edwin E. Yaz Aug 2014

Deterministic And Stochastic Resilience Analysis Of Minimum-Time-Controlled Discrete-Time Systems, Jennifer L. Bonniwell, Susan C. Schneider Phd, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

The resilience of discrete-time systems subject to minimum-time control is analysed for both deterministic and stochastic control gain perturbations. Lyapunov analysis is used to determine a tight upper bound on the control gain perturbations to maintain asymptotic stability.


Stochastic Analysis Of Cascading-Failure Dynamics In Power Grids, Mahshid Rahnamay-Naeini, Zhuoyao Wang, Nasir Ghani, Andrea Mammoli, Majeed M. Hayat Jul 2014

Stochastic Analysis Of Cascading-Failure Dynamics In Power Grids, Mahshid Rahnamay-Naeini, Zhuoyao Wang, Nasir Ghani, Andrea Mammoli, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

A scalable and analytically tractable probabilistic model for the cascading failure dynamics in power grids is constructed while retaining key physical attributes and operating characteristics of the power grid. The approach is based upon extracting a reduced abstraction of large-scale power grids using a small number of aggregate state variables while modeling the system dynamics using a continuous-time Markov chain. The aggregate state variables represent critical power-grid attributes, which have been shown, from prior simulation-based and historical-data-based analysis, to strongly influence the cascading behavior. The transition rates among states are formulated in terms of certain parameters that capture grid's operating …


Analysis Of Sensor Signals And Quantification Of Analytes Based On Estimation Theory, Karthick Sothivelr Jul 2014

Analysis Of Sensor Signals And Quantification Of Analytes Based On Estimation Theory, Karthick Sothivelr

Master's Theses (2009 -)

Compact sensor systems for on-site monitoring of groundwater for trace organic compounds are currently under development. To permit near real-time analysis of samples containing multiple analytes, the present work investigates a sensor signal processing approach based on estimation theory, specifically using Kalman Filter and Extended Kalman Filter. As a first step towards the analysis of groundwater samples containing multiple compounds, the approach presented in this work permits estimation of analyte concentration(s) in binary mixtures and single analyte samples on-line, before the sensor response reaches steady-state. Sensor signals from binary mixtures and single analyte samples of BTEX compounds (benzene, toluene, ethylbenzene, …


Analysis Of The Detection Of Organophosphate Pesticides In Aqueous Solutions Using Polymer-Coated Single Idt Sensors, Michael J. Mccarthy Jul 2014

Analysis Of The Detection Of Organophosphate Pesticides In Aqueous Solutions Using Polymer-Coated Single Idt Sensors, Michael J. Mccarthy

Master's Theses (2009 -)

The single interdigital transducer (IDT) device was investigated as a micro-chemical sensor for the detection of organophosphates compounds in aqueous solutions. The compounds of interest are: parathion, parathion-methyl, and paraoxon. The polymers used as a partially-selective coating for the direct detection of these compounds are 2,2'-diallylbisphenol A- 1,1,3,3,5,5-hexamethyltrisiloxane (BPA-HMTS) and polyepichlorohydrin (PECH). BPA-HMTS is synthesized here at Marquette University. The measurement of interest for the single IDT is the change radiation resistance. The radiation resistance represents the energy stored in the propagating acoustic wave. As analyte absorbs into the polymer coating, changes in the film's properties will undergo resulting in …


Terahertz Photoacoustic Spectroscopy Using An Mems Cantilever Sensor, Nathan E. Giauvitz, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie Jun 2014

Terahertz Photoacoustic Spectroscopy Using An Mems Cantilever Sensor, Nathan E. Giauvitz, Ronald A. Coutu Jr., Ivan R. Medvedev, Douglas T. Petkie

Electrical and Computer Engineering Faculty Research and Publications

In this paper, a microelectromechanical systems cantilever sensor was designed, modeled, and fabricated to measure the photoacoustic (PA) response of gases under very low vacuum conditions. The micromachined devices were fabricated using silicon-on-insulator wafers and then tested in a custom-built, miniature, vacuum chamber during this first-ever demonstration. Terahertz radiation was amplitude modulated to excite the gas under test and perform PA molecular spectroscopy. Experimental data show a predominantly linear response that directly correlates measured cantilever deflection to PA signals. Excellent low pressure (i.e., 2-40 mTorr) methyl cyanide PA spectral data were collected resulting in a system sensitivity of 1.97 × …


Reduction Of Vibration-Induced Artifacts In Synthetic Aperture Radar Imagery, Qi Wang, Matthew Pepin, Aleck Wright, Ralf Dunkel, Tom Atwood, Balu Santhanam, Walter Gerstle, Armin W. Doerry, Majeed M. Hayat Jun 2014

Reduction Of Vibration-Induced Artifacts In Synthetic Aperture Radar Imagery, Qi Wang, Matthew Pepin, Aleck Wright, Ralf Dunkel, Tom Atwood, Balu Santhanam, Walter Gerstle, Armin W. Doerry, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Target vibrations introduce nonstationary phase modulation, which is termed the micro-Doppler effect, into returned synthetic aperture radar (SAR) signals. This causes artifacts, or ghost targets, which appear near vibrating targets in reconstructed SAR images. Recently, a vibration estimation method based on the discrete fractional Fourier transform (DFrFT) has been developed. This method is capable of estimating the instantaneous vibration accelerations and vibration frequencies. In this paper, a deghosting method for vibrating targets in SAR images is proposed. For single-component vibrations, this method first exploits the estimation results provided by the DFrFT-based vibration estimation method to reconstruct the instantaneous vibration displacements. …


Electrical Machine Topologies: Hottest Topics In The Electrical Machine Research Community, Aldo Boglietti, Ayman M. El-Refaie, Oliver Drubel, Avoki M. Omekanda, Nicola Bianchi, Emmanuel B. Agamloh, Mircea Popescu, Antonino Di Gerlando, James Borg Bartolo Jun 2014

Electrical Machine Topologies: Hottest Topics In The Electrical Machine Research Community, Aldo Boglietti, Ayman M. El-Refaie, Oliver Drubel, Avoki M. Omekanda, Nicola Bianchi, Emmanuel B. Agamloh, Mircea Popescu, Antonino Di Gerlando, James Borg Bartolo

Electrical and Computer Engineering Faculty Research and Publications

In this article, the state of the art in electrical machine design is outlined underlining the problems and challenges to be solved by engineers. As highlighted in this article, even if electrical machine design is often considered a mature issue from the technical and technological point of view, every year, new progresses and steps forward are made. New and more sophisticated design tools can be used worldwide, and innovative manufacturing processes, new insulation materials, and higher performance magnetic materials are available on the market. In addition, the evolution of the hardware used in digital control and new powerful power electronic …


Sensorimotor Adaptation Of Speech Using Real-Time Articulatory Resynthesis, Jeffrey J. Berry, Cassandra North, Michael T. Johnson May 2014

Sensorimotor Adaptation Of Speech Using Real-Time Articulatory Resynthesis, Jeffrey J. Berry, Cassandra North, Michael T. Johnson

Speech Pathology and Audiology Faculty Research and Publications

Sensorimotor adaptation is an important focus in the study of motor learning for non-disordered speech, but has yet to be studied substantially for speech rehabilitation. Speech adaptation is typically elicited experimentally using LPC resynthesis to modify the sounds that a speaker hears himself producing. This method requires that the participant be able to produce a robust speech-acoustic signal and is therefore not well-suited for talkers with dysarthria. We have developed a novel technique using electromagnetic articulography (EMA) to drive an articulatory synthesizer. The acoustic output of the articulatory synthesizer can be perturbed experimentally to study auditory feedback effects on sensorimotor …


The Electromagnetic Articulography Mandarin Accented English (Ema-Mae) Corpus Of Acoustic And 3d Articulatory Kinematic Data, Jeffrey J. Berry, An Ji, Michael T. Johnson May 2014

The Electromagnetic Articulography Mandarin Accented English (Ema-Mae) Corpus Of Acoustic And 3d Articulatory Kinematic Data, Jeffrey J. Berry, An Ji, Michael T. Johnson

Speech Pathology and Audiology Faculty Research and Publications

There is a significant need for more comprehensive electromagnetic articulography (EMA) datasets that can provide matched acoustics and articulatory kinematic data with good spatial and temporal resolution. The Marquette University Electromagnetic Articulography Mandarin Accented English (EMA-MAE) corpus provides kinematic and acoustic data from 40 gender and dialect balanced speakers representing 20 Midwestern standard American English L1 speakers and 20 Mandarin Accented English (MAE) L2 speakers, half Beijing region dialect and half are Shanghai region dialect. Three dimensional EMA data were collected at a 400 Hz sampling rate using the NDI Wave system, with articulatory sensors on the midsagittal lips, lower …


Model-Based Edge Detector For Spectral Imagery Using Sparse Spatiospectral Masks, Biliana S. Paskaleva, Sebastian E. Godoy, Woo-Yong Jang, Steven C. Bender, Sanjay Krishna, Majeed M. Hayat May 2014

Model-Based Edge Detector For Spectral Imagery Using Sparse Spatiospectral Masks, Biliana S. Paskaleva, Sebastian E. Godoy, Woo-Yong Jang, Steven C. Bender, Sanjay Krishna, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Two model-based algorithms for edge detection in spectral imagery are developed that specifically target capturing intrinsic features such as isoluminant edges that are characterized by a jump in color but not in intensity. Given prior knowledge of the classes of reflectance or emittance spectra associated with candidate objects in a scene, a small set of spectral-band ratios, which most profoundly identify the edge between each pair of materials, are selected to define a edge signature. The bands that form the edge signature are fed into a spatial mask, producing a sparse joint spatiospectral nonlinear operator. The first algorithm achieves edge …


Evaluation Of The Importance Of Time-Frequency Contributions To Speech Intelligibility In Noise, Chengzhu Yu, Kamil K. Wójcicki, Philipos C. Loizou, John H. L. Hansen, Michael T. Johnson May 2014

Evaluation Of The Importance Of Time-Frequency Contributions To Speech Intelligibility In Noise, Chengzhu Yu, Kamil K. Wójcicki, Philipos C. Loizou, John H. L. Hansen, Michael T. Johnson

Electrical and Computer Engineering Faculty Research and Publications

Recent studies on binary masking techniques make the assumption that each time-frequency (T-F) unit contributes an equal amount to the overall intelligibility of speech. The present study demonstrated that the importance of each T-F unit to speech intelligibility varies in accordance with speech content. Specifically, T-F units are categorized into two classes, speech-present T-F units and speech-absent T-F units. Results indicate that the importance of each speech-present T-F unit to speech intelligibility is highly related to the loudness of its target component, while the importance of each speech-absent T-F unit varies according to the loudness of its masker component. Two …


A Novel On-Chip Three-Dimensional Micromachined Calorimeter With Fully Enclosed And Suspended Thin-Film Chamber For Thermal Characterization Of Liquid Samples, Benyamin Davaji, Hye Jeong Bak, Woo-Jin Chang, Chung-Hoon Lee May 2014

A Novel On-Chip Three-Dimensional Micromachined Calorimeter With Fully Enclosed And Suspended Thin-Film Chamber For Thermal Characterization Of Liquid Samples, Benyamin Davaji, Hye Jeong Bak, Woo-Jin Chang, Chung-Hoon Lee

Electrical and Computer Engineering Faculty Research and Publications

A microfabricated calorimeter (μ-calorimeter) with an enclosed reaction chamber is presented. The 3D micromachined reaction chamber is capable of analyzing liquid samples with volume of 200 nl. The thin film low-stress silicon nitride membrane is used to reduce thermal mass of the calorimeter and increase the sensitivity of system. The μ-calorimeter has been designed to perform DC and AC calorimetry, thermal wave analysis, and differential scanning calorimetry. The μ-calorimeter fabricated with an integrated heater and a temperature sensor on opposite sides of the reaction chamber allows to perform thermal diffusivity and specific heat measurements on liquid samples with same device. …


Using The K-Means Clustering Algorithm To Classify Features For Choropleth Maps, Mark Polczynski, Michael Polczynski Apr 2014

Using The K-Means Clustering Algorithm To Classify Features For Choropleth Maps, Mark Polczynski, Michael Polczynski

Electrical and Computer Engineering Faculty Research and Publications

Common methods for classifying choropleth map features typically form classes based on a single feature attribute. This technical note reviews the use of the k-means clustering algorithm to perform feature classification using multiple feature attributes. The k-means clustering algorithm is described and compared to other common classification methods, and two examples of choropleth maps prepared using k-means clustering are provided.


Reliability Of Heterogeneous Distributed Computing Systems In The Presence Of Correlated Failures, Jorge E. Pezoa, Majeed M. Hayat Apr 2014

Reliability Of Heterogeneous Distributed Computing Systems In The Presence Of Correlated Failures, Jorge E. Pezoa, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

While the reliability of distributed-computing systems (DCSs) has been widely studied under the assumption that computing elements (CEs) fail independently, the impact of correlated failures of CEs on the reliability remains an open question. Here, the problem of modeling and assessing the impact of stochastic, correlated failures on the service reliability of applications running on DCSs is tackled. The service reliability is modeled using an integrated analytical and Monte-Carlo (MC) approach. The analytical component of the model comprises a generalization of a previously developed model for reliability of non-Markovian DCSs to a setting where specific patterns of simultaneous failures in …


Analysis Of Power Converter's Control Techniques In Grid-Tie And Ac Micro/Smart Grid, Abdulgafor Mohammed Alfares Apr 2014

Analysis Of Power Converter's Control Techniques In Grid-Tie And Ac Micro/Smart Grid, Abdulgafor Mohammed Alfares

Master's Theses (2009 -)

Power converters have an outstanding potential in micro and smart grid applications that require flexible and fast power control as well as rigid voltage regulation at the point of common coupling. Power converters are required to properly operate under several modes of operation such as grid-tie and micro-grid modes of operations. In addition, the control system should be designed to enable proper load sharing between several units. Several control techniques have been proposed in the literature to address most of the control requirements of the power converters under different operating modes mentioned above. However, references found in the literatures are …


Blending As A Multi-Horizon Time Series Forecasting Tool, Tian Gao Apr 2014

Blending As A Multi-Horizon Time Series Forecasting Tool, Tian Gao

Master's Theses (2009 -)

Every day, millions of cubic feet of natural gas is transported through interstate pipelines and consumed by customers all over the United States of America. Gas distributors, responsible for sending natural gas to individual customers, are eager for an estimate of how much natural gas will be used in the near future. GasHour software, a reliable forecasting tool from the Marquette University GasDay lab, has been providing highly accurate hourly forecasts over the past few years. Our goal is to improve current GasHour forecasts, and my thesis presents an approach to achieve that using a blending technique. This thesis includes …


Using Evolutionary Programming To Increase The Accuracy Of An Ensemble Model For Energy Forecasting, James Gramz Apr 2014

Using Evolutionary Programming To Increase The Accuracy Of An Ensemble Model For Energy Forecasting, James Gramz

Master's Theses (2009 -)

Natural gas companies are always trying to increase the accuracy of their forecasts. We introduce evolutionary programming as an approach to forecast natural gas demand more accurately. The created Evolutionary Programming Engine and Evolutionary Programming Ensemble Model use the current GasDay models, along with weather and historical ow to create an overall forecast for the amount of natural gas a company will need to supply to their customers on a given day. The existing ensemble model uses the GasDay component models and then tunes their individual forecasts and combines them to create an overall forecast. The inputs into the Evolutionary …