Engineering Commons^™

Helicopters As A Theme In A Machine Design Course, Devin Turner, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

Helicopters as a Theme in Teaching Machine Design A machine design course is required in most undergraduate mechanical engineering curricula. This course generally covers an introduction to mechanical engineering design, a review of materials engineering, a review of mechanics of materials (shear force and bending moment diagrams, stress and strain analysis, deflection and stiffness analysis of beams, columns, etc.),models for failure due to static loading and variable fatigue, and then presents (in somewhat arbitrary order) the design of specific mechanical elements: shafts, fasteners, springs, bearings, gears, flexible elements such as belts, chain, and wire rope, clutches, brakes, couplings, etc. For …

Machine Design Experiments Using Mechanical Springs To Foster Discovery Learning, Peter William Malak, Mark L. Nagurka

Mechanical Engineering Faculty Research and Publications

Machine Design Experiments Using Mechanical Springs to Foster Discover Learning For the typical undergraduate engineering student the topic of mechanical springs is introduced and discussed in several courses. A first exposure may be in a physics course, where springs are presented as idealized mechanical energy storage components. Springs store potential energy,complementing masses that store kinetic energy and dampers that are resistive and offer no energy storage capability. In an electrical circuit course, springs are often presented as the analog of either capacitors or inductors, depending on which analogy is used. For mechanical engineering students, springs are a core component studied …

Learning Redundant Motor Tasks With And Without Overlapping Dimensions: Facilitation And Interference Effects, Rajiv Ranganathan, Jon A. Wieser, Kristine M. Mosier, Ferdinando A. Mussa-Ivaldi, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Prior learning of a motor skill creates motor memories that can facilitate or interfere with learning of new, but related, motor skills. One hypothesis of motor learning posits that for a sensorimotor task with redundant degrees of freedom, the nervous system learns the geometric structure of the task and improves performance by selectively operating within that task space. We tested this hypothesis by examining if transfer of learning between two tasks depends on shared dimensionality between their respective task spaces. Human participants wore a data glove and learned to manipulate a computer cursor by moving their fingers. Separate groups of …

The Impacts Of Triclosan On Anaerobic Community Structures, Function, And Antimicrobial Resistance, Patrick J. Mcnamara, Timothy M. Lapara, Paige J. Novak

Civil and Environmental Engineering Faculty Research and Publications

Triclosan is a widespread antimicrobial agent that accumulates in anaerobic digesters used to treat the residual solids generated at municipal wastewater treatment plants; there is very little information, however, about how triclosan impacts microbial communities in anaerobic digesters. We investigated how triclosan impacts the community structure, function and antimicrobial resistance genes in lab-scale anaerobic digesters. Previously exposed (to triclosan) communities were amended with 5, 50, and 500 mg/kg of triclosan, corresponding to the median, 95th percentile, and 4-fold higher than maximum triclosan concentration that has been detected in U.S. biosolids. Triclosan amendment caused all of the Bacteria and Archaea communities …

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

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 …

Electroencephalogram Coherence In Children With And Without Autism Spectrum Disorders: Decreased Interhemispheric Connectivity In Autism, Audrey Meyer Carson, Nicole M.G. Salowitz, Robert A. Scheidt, Bridget K. Dolan, Amy V. Van Hecke

Biomedical Engineering Faculty Research and Publications

Electroencephalogram coherence was measured in children with autism spectrum disorders (ASD) and control children at baseline and while watching videos of a familiar and unfamiliar person reading a story. Coherence was measured between the left and right hemispheres of the frontal, parietal, and temporal-parietal lobes (interhemispheric) and between the frontal and parietal lobes in each hemisphere (intrahemispheric). A data-reduction technique was employed to identify the frequency (alpha) that yielded significant differences in video conditions. Children with ASD displayed reduced coherence at the alpha frequency between the left and right temporal-parietal lobes in all conditions and reduced coherence at the alpha …

In Vivo Imaging Of Human Cone Photoreceptor Inner Segments, Drew Scoles, Yusufu N. Sulai, Christopher S. Langlo, Gerald A. Fishman, Christine A. Curcio, Joseph Carroll, Alfredo Dubra

Biomedical Engineering Faculty Research and Publications

Purpose.

An often overlooked prerequisite to cone photoreceptor gene therapy development is residual photoreceptor structure that can be rescued. While advances in adaptive optics (AO) retinal imaging have recently enabled direct visualization of individual cone and rod photoreceptors in the living human retina, these techniques largely detect strongly directionally-backscattered (waveguided) light from normal intact photoreceptors. This represents a major limitation in using existing AO imaging to quantify structure of remnant cones in degenerating retina.

Methods.

Photoreceptor inner segment structure was assessed with a novel AO scanning light ophthalmoscopy (AOSLO) differential phase technique, that we termed nonconfocal split-detector, in two healthy …

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 …

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 …

An Ecohydrological Perspective On Drought-Induced Forest Mortality, Anthony J. Parolari, Gabriel Katul, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Regional‐scale drought‐induced forest mortality events are projected to become more frequent under future climates due to changes in rainfall patterns. The occurrence of these mortality events is driven by exogenous factors such as frequency and severity of drought and endogenous factors such as tree water and carbon use strategies. To explore the link between these exogenous and endogenous factors underlying forest mortality, a stochastic ecohydrological framework that accounts for random arrival and length of droughts as well as responses of tree water and carbon balance to soil water deficit is proposed. The main dynamics of this system are characterized with …

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. …

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 …

Feedback Regulation Of Limb Position Characterized Using Fmri, Aaron J. Suminski, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Faculty Internships For Capstone Design Instructors: Maintaining An Up-To-Date Capstone Design Course, Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Robotic Resistance/Assistance Training Improves Locomotor Function In Individuals Poststroke: A Randomized Controlled Study, Ming Wu, Jill M. Landry, Janis Kim, Brian D. Schmit, Sheng-Che Yen, Jillian Macdonald

Biomedical Engineering Faculty Research and Publications

Objective

To determine whether providing a controlled resistance versus assistance to the paretic leg at the ankle during treadmill training will improve walking function in individuals poststroke.

Design

Repeated assessment of the same patients with parallel design and randomized controlled study between 2 groups.

Setting

Research units of rehabilitation hospitals.

Participants

Patients (N=30) with chronic stroke.

Intervention

Subjects were stratified based on self-selected walking speed and were randomly assigned to the resistance or assistance training group. For the resistance group, a controlled resistance load was applied to the paretic leg at the ankle to resist leg swing during treadmill walking. …

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 …

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 …

The Derivation Of Euler's Equations Of Motion In Cylindrical Vector Components To Aid In Analyzing Single Axis Rotation, James J. Jennings

Master's Theses (2009 -)

The derivation of Euler's equations of motion in using cylindrical vector components is beneficial in more intuitively describing the parameters relating to the balance of rotating machinery. Using the well established equation for Newton's equations in moment form and changing the position and angular velocity vectors to cylindrical vector components results in a set of equations defined in radius-theta space rather than X-Y space. This easily allows for the graphical representation of the intuitive design parameters effect on the resulting balance force that can be used to examine the robustness of a design. The sensitivity of these parameters and their …

Computational Evaluation Of Shear Stress And Restenosis In Stented Coronary Arteries Using Optical Coherence Tomography, Joshua K. Hughey

Master's Theses (2009 -)

The cause of coronary artery neointimal thickness (NT) leading to restenosis in ~10% of drug-eluting stents (DES) is unknown, but adverse wall shear stress (WSS) may contribute. Prior studies comparing WSS to restenosis for first generation DES yielded conflicting results, and cited different mechanisms of action for DES agents. Studies to date have not accounted for stent geometry, which dictates local WSS patterns influencing drug concentration. The objective of this investigation was to evaluate current generation stent platforms via their WSS patterns and their respective impact on NT. We prospectively enrolled 19 patients, who were randomized to thin-strut (81μm) 2-link …

Markerless Analysis Of Upper Extremity Kinematics During Standardized Pediatric Assessment, Jacob R. Rammer

Master's Theses (2009 -)

Children with hemiplegic cerebral palsy experience reduced motor performance in the affected upper extremity and are typically evaluated based on degree of functional impairment using activity-based assessments such as the Shriners Hospitals for Children Upper Extremity Evaluation (SHUEE), a validated clinical measure, to describe performance prior to and following rehabilitative or surgical interventions. Evaluations rely on subjective therapist scoring techniques and lack sensitivity to detect change. Objective clinical motion analysis systems are an available but time-consuming and cost-intensive alternative, requiring uncomfortable application of markers to the patient. There is currently no available markerless, low-cost system that quantitatively assesses upper extremity …

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 …

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 …

A One-Dimensional Model Of A Closed-Loop Refrigeration Test Block For Centrifugal Compressors, Paul D. Gessler

Master's Theses (2009 -)

The increasingly competitive building equipment and control industry pushes manufacturers to continually improve the performance and efficiency of their products to develop and maintain a competitive edge. Compressor development is an expensive endeavor, but the cost and time required for testing can be minimized by developing a model of the compressor test block to predict its behavior with a given prototype compressor at specified operating conditions. This thesis presents a thermodynamic model of a hot gas bypass test block used to evaluate centrifugal compressor performance at a compressor development facility. The test block uses cooling towers to reject the heat …

A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Background: Proprioception plays important roles in planning and control of limb posture and movement. The impact of proprioceptive deficits on motor function post-stroke has been difficult to elucidate due to limitations in current tests of arm proprioception. Common clinical tests only provide ordinal assessment of proprioceptive integrity (eg. intact, impaired or absent). We introduce a standardized, quantitative method for evaluating proprioception within the arm on a continuous, ratio scale. We demonstrate the approach, which is based on signal detection theory of sensory psychophysics, in two tasks used to characterize motor function after stroke.

Methods: Hemiparetic stroke survivors and neurologically intact …

Long-Term Results Of Comprehensive Clubfoot Release Versus The Ponseti Method: Which Is Better?, Peter A. Smith, Ken N. Kuo, Adam Graf, Joseph Krzak, Ann Flanagan, Sahar Hassani, Angela Caudill, Frederick Dietz, Jose Morcuende, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

Background

Clubfoot can be treated nonoperatively, most commonly using a Ponseti approach, or surgically, most often with a comprehensive clubfoot release. Little is known about how these approaches compare with one another at longer term, or how patients treated with these approaches differ in terms of foot function, foot biomechanics, or quality-of-life from individuals who did not have clubfoot as a child.

Questions/purposes

We compared (1) focused physical and radiographic examinations, (2) gait analysis, and (3) quality-of-life measures at long-term followup between groups of adult patients with clubfoot treated either with the Ponseti method of nonsurgical management or a comprehensive …

Design And Development Of An Affordable Haptic Robot With Force-Feedback And Compliant Actuation To Improve Therapy For Patients With Severe Hemiparesis, Andrew R. Theriault, Mark L. Nagurka, Michelle J. Johnson

Mechanical Engineering Faculty Research and Publications

The study describes the design and development of a single degree-of-freedom haptic robot, Haptic Theradrive, for post-stroke arm rehabilitation for in-home and clinical use. The robot overcomes many of the weaknesses of its predecessor, the TheraDrive system, that used a Logitech steering wheel as the haptic interface for rehabilitation. Although the original TheraDrive system showed success in a pilot study, its wheel was not able to withstand the rigors of use. A new haptic robot was developed that functions as a drop-in replacement for the Logitech wheel. The new robot can apply larger forces in interacting with the patient, thereby …

Quantification Of Local Hemodynamic Alterations Caused By Virtual Implantation Of Three Commercially Available Stents For The Treatment Of Aortic Coarctation, Sung Kwon, Jeffrey A. Feinstein, Ronak Jashwant Dholakia, John F. Ladisa

Biomedical Engineering Faculty Research and Publications

Patients with coarctation of the aorta (CoA) are prone to morbidity including atherosclerotic plaque that has been shown to correlate with altered wall shear stress (WSS) in the descending thoracic aorta (dAo). We created the first patient-specific computational fluid dynamics (CFD) model of a CoA patient treated by Palmaz stenting to date, and compared resulting WSS distributions to those from virtual implantation of Genesis XD and modified NuMED CP stents, also commonly used for CoA. CFD models were created from magnetic resonance imaging, fluoroscopy and blood pressure data. Simulations incorporated vessel deformation, downstream vascular resistance and compliance to match measured …

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

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 …