Engineering Commons^™

The Arm Motion (Amd) Detection Test, Maria C. Bengston, Leigh A. Mrotek, Tina M. Stoeckmann, Claude Ghez, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Stroke can lead to sensory deficits that impair functional control of arm movements. Here we describe a simple test of arm motion detection (AMD) that provides an objective, quantitative measure of movement perception related proprioceptive capabilities in the arm. Seven stroke survivors and thirteen neurologically intact control subjects performed the AMD test. In a series of ten trials that took less than 15 minutes to complete, participants used a two-button user interface to adjust the magnitude of hand displacements produced by a horizontal planar robot until the motions were just perceptible (i.e. on the threshold of detection). The standard deviation …

Characterization Of A Human Powered Nebulizer Compressor For Resource Poor Settings, Christopher J. Hallberg, Mary Therese Lysaught, Christopher E. Zmudka, William K. Kopesky, Lars E. Olson

Biomedical Engineering Faculty Research and Publications

Background

Respiratory disease accounts for three of the ten leading causes of death worldwide. Many of these diseases can be treated and diagnosed using a nebulizer. Nebulizers can also be used to safely and efficiently deliver vaccines. Unfortunately, commercially available nebulizers are not designed for use in regions of the world where lung disease is most prevalent: they are electricity-dependent, cost-prohibitive, and not built to be reliable in harsh operating conditions or under frequent use.

To overcome these limitations, the Human Powered Nebulizer compressor (HPN) was developed. The HPN does not require electricity; instead airflow is generated manually through a …

Which Design And Biomaterial Factors Affect Clinical Wear Performance Of Total Disc Replacements? A Systematic Review, Sai Y. Veruva, Marla J. Steinbeck, Jeffrey M. Toth, Dominik D. Alexander, Steven M. Kurtz

Biomedical Engineering Faculty Research and Publications

Background

Total disc replacement was clinically introduced to reduce pain and preserve segmental motion of the lumbar and cervical spine. Previous case studies have reported on the wear and adverse local tissue reactions around artificial prostheses, but it is unclear how design and biomaterials affect clinical outcomes.

Questions/purposes

Which design and material factors are associated with differences in clinical wear performance (implant wear and periprosthetic tissue response) of (1) lumbar and (2) cervical total disc replacements?

Methods

We performed a systematic review on the topics of implant wear and periprosthetic tissue response using an advanced search in MEDLINE and Scopus …

Evaluation Of Upper Extremity Movement Characteristics During Standardized Pediatric Functional Assessment With A Kinect®-Based Markerless Motion Analysis System, Jacob R. Rammer, Joseph J. Krzak, Susan A. Riedel, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

A recently developed and evaluated upper extremity (UE) markerless motion analysis system based on the Microsoft® Kinect® has potential for improving functional assessment of patients with hemiplegic cerebral palsy. 12 typically-developing adolescents ages 12-17 were evaluated using both the Kinect-based system and the Shriners Hospitals for Children Upper Extremity Evaluation (SHUEE), a validated measure of UE motion. The study established population means of UE kinematic parameters for each activity. Statistical correlation analysis was used to identify key kinematic metrics used to develop automatic scoring algorithms. The Kinect motion analysis platform is technically sound and can be applied to standardized task-based …

Diffusion Tensor Imaging Of The Spinal Cord: Insights From Animal And Human Studies, Aditya Vedantam, Michael B. Jirjis, Brian D. Schmit, Marjorie C. Wang, John L. Ulmer, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

Diffusion tensor imaging (DTI) provides a measure of the directional diffusion of water molecules in tissues. The measurement of DTI indexes within the spinal cord provides a quantitative assessment of neural damage in various spinal cord pathologies. DTI studies in animal models of spinal cord injury indicate that DTI is a reliable imaging technique with important histological and functional correlates. These studies demonstrate that DTI is a noninvasive marker of microstructural change within the spinal cord. In human studies, spinal cord DTI shows definite changes in subjects with acute and chronic spinal cord injury, as well as cervical spondylotic myelopathy. …

Evaluation Of Forearm Muscle Fatigue From Operating A Motorcycle Clutch, Megan O. Conrad, Richard W. Marklin

Mechanical Engineering Faculty Research and Publications

A laboratory experiment evaluated the effect of motorcycle clutch design on the electromyography (EMG) activity of the primary agonist finger flexor muscle in the forearm. The goal was to compare muscle fatigue resulting from operation of two different motorcycle clutches in simulated traffic. EMG activity from the flexor digitorum superficialis (FDS) muscle of 12 female and 11 males were recorded while each participant operated an existing motorcycle clutch (requiring 98 N peak force) as well as an alternate design (requiring 36 N peak force) during 60-minute simulations. Muscle fatigue was quantified by measuring the decrease in median frequency of the …

Simultaneous Robotic Manipulation And Functional Magnetic Resonance Imaging: Feasibility In Children With Autism Spectrum Disorders, Nicole M.G. Salowitz, Bridget Dolan, Rheanna Remmel, Amy V. Van Hecke, Kristine M. Mosier, Lucia Simo, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

An unanswered question concerning the neural basis of autism spectrum disorders (ASD) is how sensorimotor deficits in individuals with ASD are related to abnormalities of brain function. We previously described a robotic joystick and video game system that allows us to record functional magnetic resonance images (FMRI) while adult humans make goal-directed wrist motions. We anticipated several challenges in extending this approach to studying goal-directed behaviors in children with ASD and in typically developing (TYP) children. In particular we were concerned that children with autism may express increased levels of anxiety as compared to typically developing children due to the …

Submovements During Reaching Movements After Stroke, Lucia S. Simo, Davide Piovesan, Jozsef Laczko, Claude Ghez, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Neurological deficits after cerebrovascular accidents very frequently disrupt the kinematics of voluntary movements with the consequent impact in daily life activities. Robotic methodologies enable the quantitative characterization of specific control deficits needed to understand the basis of functional impairments and to design effective rehabilitation therapies. In a group of right handed chronic stroke survivors (SS) with right side hemiparesis, intact proprioception, and differing levels of motor impairment, we used a robotic manipulandum to study right arm function during discrete point-to-point reaching movements and reciprocal out-and-back movements to visual targets. We compared these movements with those of neurologically intact individuals (NI). …

A Modular Low-Clearance Wrist Orthosis For Improving Wrist Motion In Children With Cerebral Palsy, Devon Holley, Michelle Johnson, Gerald F. Harris, Scott A. Beardsley

Biomedical Engineering Faculty Research and Publications

Children with Cerebral Palsy (CP) often exhibit impairments in the coordination of the grip and lift phases of arm movements that directly impact their ability to perform activities of daily living (ADLs). The application of assistive robotic therapy to children with spastic hemiplegic CP has shown that augmented movement training can lead to improved functional outcomes and improved arm kinematics. Assistive robotic therapy of the wrist has been shown to help improve motor skills in stroke patients, but the devices employed are often large and obtrusive, focusing on a repeated motion rather than a task-based itinerary. Here, we propose a …

Developing An At-Home System For Evaluating Manual Wheelchair Propulsion And Directing Rehabilitative Training To Optimize Biomechanical Efficiency, Gerald F. Harris

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Benefits Of Industry Involvement In Multidisciplinary Capstone Design Courses, Jay R. Goldberg, Vikram Cariapa, George Corliss, Kate Kaiser

Biomedical Engineering Faculty Research and Publications

Opportunities for industry involvement in capstone design courses go beyond industry sponsorship of capstone design projects. Representatives from industry can serve as guest lecturers, curriculum advisors, and design project sponsors and team mentors. Since 2000, industry participation has been a core part of the capstone design course at Marquette University. Practicing engineers provide a relevant, practical real-world perspective of their topic, reinforcing its importance to professional engineering practice. Students and faculty benefit from the up-to-date treatment of the topic provided by guest speakers from industry who have expertise in the topic and are willing to share their experiences with students. …

Lightweight Data Compression In Wireless Sensor Networks Using Huffman Coding, Henry P. Medeiros, Marcos C. Maciel, Richard D. Souza, Marcelo E. Pellenz

Electrical and Computer Engineering Faculty Research and Publications

This paper presents a lightweight data compression method for wireless sensor networks monitoring environmental parameters with low resolution sensors. Instead of attempting to devise novel ad hoc algorithms, we show that, given general knowledge of the parameters that must be monitored, it is possible to efficiently employ conventional Huffman coding to represent the same parameter when measured at different locations and time periods. When the data collected by the sensor nodes consists of integer measurements, the Huffman dictionary computed using statistics inferred from public datasets often approaches the entropy of the data. Results using temperature and relative humidity measurements show …

Thermal Tuning Of Mems Buckled Membrane Actuator Stiffness, Robert A. Lake, Kyle K. Ziegler, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

The thermal tuning characteristics of a microelectromechanical systems (MEMS) buckled membrane exhibiting regions of both positive and negative stiffness is examined and analyzed using finite element method (FEM) simulation and through experimentation. The membranes are fabricated by releasing a silicon/silicon dioxide (Si/SiO₂) laminated membrane from a silicon on insulator (SOI) wafer. The difference in thermal expansion coefficients between Si and SiO2 induces a compressive stress in the SiO₂ layer causing out-of-plane buckling of the membrane. This structure is found to have positive and negative stiffness regions when actuated with a transverse force. It is demonstrated that the …

Beluga Whale Vocalizations, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

Sound files:

A Chirp; A Whistle ; B Chirp; B Whistle: Buzz; C Whistle; CH6 A Chirp; D Whistle; Down Warble; Down Whistle; E Whistle; Voca

African Elephant Vocalizations, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

Sound files:

Croak ; Rumble ; Rev ; Snort ; Trumpet

Finite Element Analysis Of Frp Debonding Failure At The Tip Of Flexural/Shear Crack In Concrete Beam, Tayyebeh Mohammadi, Baolin Wan, Kent Harries

Civil and Environmental Engineering Faculty Research and Publications

One of the most common failure modes of strengthened RC beams with externally bonded FRP is intermediate crack (IC) debonding of FRP initiated at the tip of flexural/shear cracks. This study presents a method, using extended finite element method (XFEM), to model IC debonding in an FRP-strengthened concrete beam. In XFEM, as soon as a damage initiation criterion is reached in an element, additional degrees of element freedom are added to model crack initiation. Crack propagation is then modeled using fracture energy criterion. This method can be used to simulate debonding failure along an arbitrary, solution-dependent path without the requirement …

Heavy Vehicle Performance During Recovery From Forced-Flow Urban Freeway Conditions Due To Incidents, Work Zones And Recurring Congestion, Alexander Drakopoulos, Yue Liu, Alan Horowitz

Civil and Environmental Engineering Faculty Research and Publications

Information contained in the Highway Capacity Manual on the influence heavy vehicles have on freeway traffic operations has been based on few field data collection efforts and relied mostly on traffic simulation efforts. In the 2010 Manual heavy vehicle impact is evaluated based on “passenger car equivalent” values for buses, recreational vehicles and trucks. These values were calibrated for relatively uncongested freeway conditions (levels of service A through C) since inadequate field data on heavy vehicle behavior under congested conditions were available. A number of field data collection efforts, that were not included in deriving the passenger car equivalent values …

Depleted Energy Charge And Increased Pulmonary Endothelial Permeability Induced By Mitochondrial Complex I Inhibition Are Mitigated By Coenzyme Q1 In The Isolated Perfused Rat Lung, Robert D. Bongard, Ke Yan, Raymond G. Hoffmann, Said H. Audi, Xiao Zhang, Brian J. Lindemer, Mary I. Townsley, Marilyn P. Merker

Biomedical Engineering Faculty Research and Publications

Mitochondrial dysfunction is associated with various forms of lung injury and disease that also involve alterations in pulmonary endothelial permeability, but the relationship, if any, between the two is not well understood. This question was addressed by perfusing isolated intact rat lung with a buffered physiological saline solution in the absence or presence of the mitochondrial complex I inhibitor rotenone (20 μM). Compared to control, rotenone depressed whole lung tissue ATP from 5.66±0.46 (SEM) to 2.34±0.15 µmol·g⁻¹ dry lung, with concomitant increases in the ADP:ATP and AMP:ATP ratios. Rotenone also increased lung perfusate lactate (from 12.36±1.64 to 38.62±3.14 µmol·15 …

The Effects Of Gantry Tilt On Breast Dose And Image Noise In Cardiac Ct, Michael Hoppe, Diksha Gandhi, Grant Stevens, Dennis Foley, Taly Gilat-Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose:

This study investigated the effects of tilted-gantry acquisition on image noise and glandular breast dose in females during cardiac computed tomography (CT) scans. Reducing the dose to glandular breast tissue is important due to its high radiosensitivity and limited diagnostic significance in cardiac CT scans.

Methods:

Tilted-gantry acquisition was investigated through computer simulations and experimental measurements. Upon IRB approval, eight voxelized phantoms were constructed from previously acquired cardiac CT datasets. Monte Carlo simulations quantified the dose deposited in glandular breast tissue over a range of tilt angles. The effects of tilted-gantry acquisition on breast dose were measured on a …

Exploiting Contextual Information For Prosodic Event Detection Using Auto-Context, Junhong Zhao, Wei-Qiang Zhang, Hua Yang, Michael T. Johnson, Jia Liu, Shanhong Xia

Electrical and Computer Engineering Faculty Research and Publications

Prosody and prosodic boundaries carry significant information regarding linguistics and paralinguistics and are important aspects of speech. In the field of prosodic event detection, many local acoustic features have been investigated; however, contextual information has not yet been thoroughly exploited. The most difficult aspect of this lies in learning the long-distance contextual dependencies effectively and efficiently. To address this problem, we introduce the use of an algorithm called auto-context. In this algorithm, a classifier is first trained based on a set of local acoustic features, after which the generated probabilities are used along with the local features as contextual information …

Visuo-Proprioceptive Interactions During Adaptation Of The Human Reach, Timothy Judkins, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

We examined whether visual and proprioceptive estimates of transient (mid-reach) target capture errors contribute to motor adaptation according to the probabilistic rules of information integration used for perception. Healthy adult humans grasped and moved a robotic handle between targets in the horizontal plane while the robot generated spring-like loads that varied unpredictably from trial-to-trial. For some trials, a visual cursor faithfully tracked hand motion. In others, the handle's position was locked and subjects viewed motion of a point-mass cursor driven by hand forces. In yet other trials, cursor feedback was dissociated from hand motion or altogether eliminated. We used time- …

Timoshenko Beam Effects In Lateral-Mode Microcantilever-Based Sensors In Liquids, Joshua A. Schultz, Stephen M. Heinrich, Fabien Josse, Nicholas J. Nigro, Isabelle Dufour, Luke A. Beardslee, Oliver Brand

Civil and Environmental Engineering Faculty Research and Publications

Recent experimental and analytical research has shown that higher in-fluid quality factors (Q) are achieved by actuating microcantilevers in the lateral flexural mode, especially for microcantilevers having larger width-to-length ratios. However, experimental results show that for these geometries the resonant characteristics predicted by the existing analytical models differ from the measurements. A recently developed analytical model to more accurately predict the resonant behaviour of these devices in viscous fluids is described. The model incorporates viscous fluid effects via a Stokes-type fluid resistance assumption and `Timoshenko beam' effects (shear deformation and rotatory inertia). Unlike predictions based on Euler-Bernoulli beam …

Calculation Of Magnet Losses In Concentrated-Winding Permanent-Magnet Synchronous Machines Using A Computationally Efficient Finite-Element Method, Peng Zhang, Gennadi Y. Sizov, Jiangbiao He, Dan M. Ionel, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

The proposed hybrid method combines computationally efficient finite-element analysis (CE-FEA) with a new analytical formulation for eddy-current losses in the permanent magnets (PMs) of sine-wave current-regulated brushless synchronous motors. The CE-FEA only employs a reduced set of magnetostatic solutions yielding substantial reductions in the computational time, as compared with the conventional FEA. The 3-D end effects and the effect of pulsewidth-modulation switching harmonics are incorporated in the analytical calculations. The algorithms are applied to two fractional-slot concentrated-winding interior PM motors with different circumferential and axial PM block segmentation arrangements. The method is validated against 2-D and 3-D time-stepping FEA.

Conditional Spectrum-Based Ground Motion Selection. Part Ii: Intensity-Based Assessments And Evaluation Of Alternative Target Spectra, Ting Lin, Curt B. Haselton, Jack W. Baker

Civil and Environmental Engineering Faculty Research and Publications

In a companion paper, an overview and problem definition was presented for ground motion selection on the basis of the conditional spectrum (CS), to perform risk-based assessments (which estimate the annual rate of exceeding a specified structural response amplitude) for a 20-story reinforced concrete frame structure. Here, the methodology is repeated for intensity-based assessments (which estimate structural response for ground motions with a specified intensity level) to determine the effect of conditioning period. Additionally, intensity-based and risk-based assessments are evaluated for two other possible target spectra, specifically the uniform hazard spectrum (UHS) and the conditional mean spectrum (CMS, without variability).It …

Conditional Spectrum-Based Ground Motion Selection. Part I: Hazard Consistency For Risk-Based Assessments, Ting Lin, Curt B. Haselton, Jack W. Baker

Civil and Environmental Engineering Faculty Research and Publications

The conditional spectrum (CS, with mean and variability) is a target response spectrum that links nonlinear dynamic analysis back to probabilistic seismic hazard analysis for ground motion selection. The CS is computed on the basis of a specified conditioning period, whereas structures under consideration may be sensitive to response spectral amplitudes at multiple periods of excitation. Questions remain regarding the appropriate choice of conditioning period when utilizing the CS as the target spectrum. This paper focuses on risk-based assessments, which estimate the annual rate of exceeding a specified structural response amplitude. Seismic hazard analysis, ground motion selection, and nonlinear dynamic …

Microelectromechanical Systems (Mems) Resistive Heaters As Circuit Protection Devices, Ronald A. Coutu Jr., Scott A. Ostrow

Electrical and Computer Engineering Faculty Research and Publications

With increased opportunities for the exploitation (i.e., reverse engineering) of vulnerable electronic components and systems, circuit protection has become a critical issue. Circuit protection techniques are generally software-based and include cryptography (encryption/decryption), obfuscation of codes, and software guards. Examples of hardware-based circuit protection include protective coatings on integrated circuits, trusted foundries, and macro-sized components that self-destruct, thus destroying critical components. This paper is the first to investigate the use of microelectromechanical systems (MEMS) to provide hardware-based protection of critical electronic components to prevent reverse engineering or other exploitation attempts. Specifically, surface-micromachined polycrystalline silicon to be used as meandering resistive heaters …

Slow Potentials Of The Sensorimotor Cortex During Rhythmic Movements Of The Ankle, Ryan J. Mckindles

Dissertations (1934 -)

The objective of this dissertation was to more fully understand the role of the human brain in the production of lower extremity rhythmic movements. Throughout the last century, evidence from animal models has demonstrated that spinal reflexes and networks alone are sufficient to propagate ambulation. However, observations after neural trauma, such as a spinal cord injury, demonstrate that humans require supraspinal drive to facilitate locomotion. To investigate the unique nature of lower extremity rhythmic movements, electroencephalography was used to record neural signals from the sensorimotor cortex during three cyclic ankle movement experiments. First, we characterized the differences in slow movement-related …

Physiologically-Motivated Feature Extraction Methods For Speaker Recognition, Jianglin Wang

Dissertations (1934 -)

Speaker recognition has received a great deal of attention from the speech community, and significant gains in robustness and accuracy have been obtained over the past decade. However, the features used for identification are still primarily representations of overall spectral characteristics, and thus the models are primarily phonetic in nature, differentiating speakers based on overall pronunciation patterns. This creates difficulties in terms of the amount of enrollment data and complexity of the models required to cover the phonetic space, especially in tasks such as identification where enrollment and testing data may not have similar phonetic coverage. This dissertation introduces new …

A Novel Design Optimization Of A Fault-Tolerant Ac Permanent Magnet Machine-Drive System, Peng Zhang

Dissertations (1934 -)

In this dissertation, fault-tolerant capabilities of permanent magnet (PM) machines were investigated. The 12-slot 10-pole PM machines with V-type and spoke-type PM layouts were selected as candidate topologies for fault-tolerant PM machine design optimization problems. The combination of 12-slot and 10-pole configuration for PM machines requires a fractional-slot concentrated winding (FSCW) layout, which can lead to especially significant PM losses in such machines. Thus, a hybrid method to compute the PM losses was investigated, which combines computationally efficient finite-element analysis (CE-FEA) with a new analytical formulation for PM eddy-current loss computation in sine-wave current regulated synchronous PM machines. These algorithms …

Design Synthesis And Optimization Of Permanent Magnet Synchronous Machines Based On Computationally-Efficient Finite Element Analysis, Gennadi Sizov

Dissertations (1934 -)

In this dissertation, a model-based multi-objective optimal design of permanent magnet ac machines, supplied by sine-wave current regulated drives, is developed and implemented. The design procedure uses an efficient electromagnetic finite element-based solver to accurately model nonlinear material properties and complex geometric shapes associated with magnetic circuit design. Application of an electromagnetic finite element-based solver allows for accurate computation in intricate performance parameters and characteristics. The first contribution of this dissertation is the development of a rapid computational method that allows accurate and efficient exploration of large multi-dimensional design spaces in search of optimum design(s). The computationally efficient finite element-based …