Category Archives: Seminars

ME-EM Graduate Seminar: Computational and Experimental Biomechanics of Total Hip Wear Increase Due to Femoral Head Damage

dec11The ME-EM Graduate Seminar speaker on Thursday, December 11 at 4:00 in 103 EERC will be Karen Krueger, Postdoctoral Fellow from Orthopaedics Department, University of Iowa.

The title of her presentation will be ‘Computational and Experimental Biomechanics of Total Hip Wear Increase Due to Femoral Head Damage’.

Aseptic loosening due to wear-induced osteolysis remains a leading cause of failure in total hip arthroplasty (THA), par-ticularly in revisions required beyond the second decade of use. Historically, there have been large amounts of variability of wear within individual THA patient cohorts. Evidence indicates that femoral head damage can be a cause of this varia-bility. While femoral head damage as a result of third body particles and subluxation and dislocation events has been well documented, direct quantifiable linkage between such femoral head damage and wear acceleration remains to be estab-lished. Due to large ranges of observed retrieval damage, wear testing protocols for simulating third body and other dam-age effects have been widely variant, making it difficult to know where the clinical reality lies.

To study the effect of retrieval femoral head damage on total hip implant wear, a damage-feature-based finite element (FE) formulation was developed, which allowed for wear prediction due to individual scratch, scrape, and transfer deposit features. A multi-scale imaging procedure was also developed to globally map and quantify micron-level damage features appearing on retrieval femoral heads. This allowed for wear simulations of damage patterns observed on specific retrieval femoral heads. Retrieval damage was shown to be highly variable among patients, and capable of producing up to order-of-magnitude wear increases when compared to undamaged heads. Damage following dislocation and subsequent closed reduction maneuvers was found to be particularly detrimental, with average wear rate increases in the range of half an or-der of magnitude. These data were used to develop wear testing protocols for simulating clinically-occurring third body and other damage effects.

Karen Kruger is currently a postdoctoral fellow in the Orthopaedics depart-ment at the University of Iowa. She earned her B.S. in mechanical engineering and biomedical engineering from Michigan Technological University while com-peting in Varsity cross country and Nordic skiing. While at Michigan Tech, she received a Michigan Space Grant to study the effectsof spaceflight on the knee joint meniscus. She went on to complete her Ph.D. in Biomedical Engineering with a focus on orthopaedic biomechanics at the University of Iowa under the direction of Dr. Thomas Brown. Her dissertation work focused on wear in total hip replacements.

ME-EM Graduate Seminar: Correlative microscopy for in situ characterization of catalyst nanoparticles under reactive environments

dec4aThe ME-EM Graduate Seminar speaker on Thursday, December 4th at 4:00 in 103 EERC will be Dr. Renu Sharma from National Institute of Standards and Technology, Center for Nanoscale Science and Technology.

The title of her presentation will be ‘Correlative microscopy for in situ characterization of catalyst nanoparticles under reactive environments’.

In recent years the environmental transmission scanning electron microscope (ESTEM) has been success-fully employed to elucidate the structural and chemical changes occurring in the catalyst nanoparticles un-der reactive environments. While atomic-resolution images and the combination of high spatial and energy resolution is ideally suited to distinguish between active and inactive catalyst particles and identify active surfaces for gas adsorption, unambiguous data can only obtained from the area under observation. This lack of statistical information available from TEM measurements is generally compensated for by using other, ensemble measurement techniques such as x-ray or neutron diffraction, x-ray photoelectron spec-troscopy, infrared spectroscopy, Raman spectroscopy etc. However, it is almost impossible to create iden-tical experimental conditions in two separate instruments to make measurements that can be directly com-pared. Moreover, ambiguities in ESTEM studies may arise from the unknown effects of the incident elec-tron beam and uncertainty of the sample temperature. We have designed and built a unique platform that allows us to concurrently measure atomic-scale and micro-scale changes occurring in samples subjected to identical reactive environmental conditions by incorporating a Raman Spectrometer on the ESTEM. We have used this correlative microscopy platform i) to measure the temperature from 60 μm2 area using Ra-man shifts, ii) to investigate light/matter interactions iii) as a heating source, iii) for concurrent optical and electron spectroscopy such as cathodoluminescence, EELS and Raman. Details of the design, function, and capabilities will be illustrated with results obtained from in situ combinatorial measurements.

Renu Sharma is a Project Leader in the Nanofabrication Research Group. She received a B.S. and B.Ed. in Physics and Chemistry from Panjab University, India, and M.S. and Ph.D. degrees in Sol-id State Chemistry from the University of Stockholm, Sweden, where she had a Swedish Institute Fellowship. Renu joined the CNST in 2009, coming from Arizona State University (ASU), where she began as a Faculty Research Associate in the Department of Chemistry and Biochemistry and the Center for Solid State Science, and most recently served as a Senior Research Scientist in the LeRoy Eyring Center for Solid State Science and as an affiliated faculty member in the School of Materials and Department of Chemical Engineering. Renu has been a pioneer in the development of environmental scanning transmission electron microscopy (E(S)TEM), combining atomic-scale dynamic imaging with chemical analysis to probe gas-solid reactions. She has applied this powerful technique to characterize the atomic-scale mechanisms underlying the synthesis and reactivity of nanoparticles (including catalysts), nanotubes, nanowires, inorganic solids, ceramics, semiconductors, and superconductor materials. Renu has received a Deutscher Akademischer Austauschdienst (DAAD) Faculty Research Fellowship, is a past President of the Arizona Im-aging and Microanalysis Society, and has given over 70 invited presentations, and published 3 book chapters and over 160 research articles. At the CNST, Renu is establishing advanced E(S)TEM measurement capabilities for nanoscience re-search and contributing her research expertise to the operation of a new TEM facility in the NanoFab.

ME-EM Graduate Seminar: Prototype Verification System PVS: Cutting Edges Human-Machine Interactive Verification, Modeling and Analysis Software

New PictureThe ME-EM Graduate Seminar speaker on Thursday, November 20th at 4:00 in 103 EERC will be Amer Tahat, PhD Student, Computational Sciences and Engineering, Department of Computer Science, Michigan Tech University,

The title of his presentation will be ‘Prototype Verification System PVS: Cutting Edges Human-Machine Interactive Verification, Modeling and Analysis Software’.

PVS is an interactive prototype verification system developed by SRI (Stanford Research Institute) with collaboration of NASA. PVS has been widely used by NASA to verify the correctness of their designs under extreme safety measures e.g Next Generation Air Traffic System (NextGen) and Scalable Processor-Independent Design for Extended Reliability (SPIDER). It has very powerful and ultra-reliable specification and semi-automatic verification language which can capture wide range of real world applications like complicated critical and autonomous control systems in: Aerodynamics, Robotics, Security and Communication Protocols. It also has been used for the design and the verifications of hardware and software of parametric critical systems, mathematical theories, and it was used even in modeling and analyzing meta-physical arguments! In this seminar we would like to introduce the revolutionary features of interactive analysis and verification system PVS. We will provide some examples of its applications in solving real life problems. Dr. Ossama Abdelkhalik (ME-EM department) and Amer Tahat PhD student (CSE) are planning to conduct a tutorial about this tool here at MTU with a generous collaboration of NASA Langley.

PVS received CAV award in 2012 ( 2012 CAV (Computer-Aided Verification) Award). PVS is an open source since 1994 and is known for its user friendliness. It has been used in industry as well as in academic research. For more information about related research fields please visit NASA formal methods group (http://shemesh.larc.nasa.gov/fm/fm-pvs.html), and PVS SRI website (http://pvs.csl.sri.com/index.shtml).

Amer Tahat is a Computational Sciences and Engineering PhD student, computer science department, at Michigan Tech University. I joined my PhD program in Sept 2012. In Oct 2012 I attended NASA Langley and National Institute of Aeronautics PVS (Prototype Verification System) class, in Hampton Virginia. Between Oct 2012 and March 2013 I was involved in a short project using PVS with the collaboration of NASA Langley. Since then I have been a member of Software Design Laboratory at Michigan Tech university and have been part of two projects under supervision of Dr. Ali Ebnenasir funded by National Science Foundation in which I study the applications of mechanical verifications using theorem prover PVS. Between 2012 and 2014, I attended and participated in several international conferences in formal and automatic verification techniques. In particular NASA Formal Methods Symposiums of Automatic Reasoning (NFM) NFM13, Moffett Field, Silicon Valley, CA and NFM14 in Johns Space Center, Huston, TX. Also in Sept 2014 I participated by a paper in LOPSTR 14 (24th International Conference of logic-Based Program Synthesis and Transformation) in UK.

In last summer 19-26 May 2014 I attended the Stanford Research International (SRI) forth summer school in formal techniques, Menlo College, Stanford, CA, in which assisted in organizing the student presentation secession. In the school I presented a PVS based analysis of a 1000 year metaphysical controversy http://fm.csl.sri.com/SSFT14/. I received an NSF generous award to attend this school.
Lately the work has been submitted to FSEN International Conference in Foundations of Software Engineering FSEN 15. Currently I am exploring more applications of PVS with the collaboration of Dr. Ossama Abedlkhalik ME-EM department on some other fields in Orbital Mechanics.

ME-EM Graduate Seminar: Positive Aspects of Negative Work

nov13The ME-EM Graduate Seminar speaker on Thursday, November 14th at 4:00 in 103 EERC will be Dr. Steven Elmer from Michigan Tech: Department of Kinesiology and Integrative Physiology.

The title of his presentation will be ‘Positive Aspects of Negative Work’.

For over 100 years, scientists have been intrigued by the observation that skeletal muscle can produce greater absolute force during active lengthening contractions (“negative work”) compared to active short-ening contractions (“positive work”). In addition to this increased capacity for force production, negative work can be performed at a lower energy cost and with less perceived effort compared to positive work. Taken together, these observations emphasize the high-force, low-cost nature of negative work and sug-gest that exercise training involving negative work could serve as a potent stimulus for improving skeletal muscle function. In this presentation, I will discuss how negative work exercise training has served as an effective method for increasing quadriceps muscle size, strength, and mobility in a variety of populations ranging from patients with chronic disease to older adults to competitive athletes. Subsequently, I will share some preliminary work in which my group has extended the application of negative work to the upper body. Along the way, I will point out some mechanical design and safety challenges that we have encoun-tered while developing the negative work lower and upper body ergometers. By the end of the presenta-tion I hope to convince the audience that if an engineer from department trained for eight weeks using negative work exercise (e.g., 10-30 minutes/session, 3 sessions/week) they would be more powerful than a Tour de France winning cyclist! On that note this presentation will highlight the “positive aspects” of “negative work”.

Steven Elmer is a new Assistant Professor in the Department of Kinesiol-ogy and Integrative Physiology at Michigan Technological University. He completed his doctoral and post-doctoral training at the University of Utah and previously worked at the University of Maine. His research in-terests in health are broad in nature and he uses a cycling model to investigate as-pects of skeletal muscle function and dysfunction. Applications for his research range from basic aspects of neuromuscular function to applied human perfor-mance in a variety of settings including injury, rehabilitation, ergonomics, and sport. As a new member of the Husky Family Dr. Elmer looks forward to devel-oping collaborations across campus.

ME-EM Graduate Seminar: Driveline Input Shaping via Clutch Torque to Mitigate Shuffle After Lash Crossing

nov06The ME-EM Graduate Seminar speaker on Thursday, November 6th at 4:00 in 103 EERC will be Dr. Jeffrey Doering from Ford Motor Company.

The title of his presentation will be ‘Driveline Input Shaping via Clutch Torque to Mitigate Shuffle After Lash Crossing’.

We will use simplified 2nd order linear equations of motion for a driveline after lash crossing to evaluate different simple torque input schemes and derive an ‘optimum’ input ramping scheme to achieve a desired steady-state driveline torque level with a minimum level of oscillation. Due to the simplicity of the type of inputs considered, closed form solutions for the driveline response are developed and evaluated to yield physical understanding of the driveline management problem after a lash crossing event, especially to pre-vent driveline rebound or shuffle. Using the stiffness, inertia and level of damping in the driveline, normal-ized ramp rates and ramp times are developed to coordinate the torque input after lash crossing with the twisting of the driveline and the initial twisting velocity at the end of lash crossing.

Jeff Doering received the B.S. in Aerospace Engineering from the University of Minnesota, Minneap-olis, in 1991 and the M.S. in Mechanical Engineering from Stanford University in 1992. In 2000, Jeff received his Ph.D. in Mechanical Engineering from Michigan Technological University. Since 1992, he has been with Ford Motor Company, Dearborn, MI, working in the areas of engine and vehicle controls in both product development and research, where he is currently a Technical Leader in Research and Advanced Engineering.
Jeff currently leads a team of engineers working on vehicle and engine controls, primarily focused on HE-V/PHEV/BEV applications. Jeff has received over 90 U.S. Patents, with approximately 30 in production in Ford vehicles.

ME-EM Graduate Seminar: Cavitation-Induced Damage in Brain Tissue and Surrogates: Relevance to TBI

oct30The ME-EM Graduate Seminar speaker on Thursday, October 30th at 4:00 in 103 EERC will be Dr. Ghatu Subhash from the University of Florida, Gainesville.

The title of his presentation will be ‘Cavitation-Induced Damage in Brain Tissue and Surrogates: Relevance to TBI’.

Traumatic brain injury (TBI) has reached epidemic proportions in US. Around 1.7 million people are diagnosed with TBI each year. While a majority of these injuries are due to physical blows that may occur because of a fall or during an athletic activity, blast-induced mild traumatic brain injury (bmTBI) is specific to soldiers who are exposed to frequent improvised explosive device (IED) blasts in a hostile environment. A blast wave consists of a high pressure front followed by a negative pressure tail. It is commonly believed that only the high pressure front causes significant damage to the brain tissue. In recent years, new evidence has emerged revealing that extensive cavitation indeed occurs in brain tissue due to the negative pressure that immediately follows the high pressure front in the blast wave. The negative pressure initiates cavitation bubbles which collapse and release shock waves, and cause significant local neuronal and astrocyte damage in sensitive areas of the brain. The current research focusses on investigating this specific phenomena in brain tissue and surrogates (e.g., gels). The first goal of this research is to develop an experimental facility to characterize cavitation in a simulated brain environment and measure associated deformation during bubble growth and collapse on a tissue surrogate. The second goal is to quantify the neuronal and astrocyte injury when a brain tissue is exposed to blast waves. A novel experimental facility has been developed to visualize controlled cavitation under high-rate stress wave loading, whose pressure profile mimics that of a blast shock wave, i.e., it contains a high pressure component followed by a negative pressure component. Highly sensitive pressure sensor measures the pressure inside the fluid filled chamber where a single air bubble is introduced at a specified location. Upon arrival of the pressure wave the bubble grows rapidly and collapses. Negative pressure magnitude, which dictates bubble growth rate and its final size, can be controlled. A high speed digital camera with frame rates up to 300,000 per second was employed to capture the tissue deformation characteristics. Digital Image Correlation (DIC) technique was employed on the gel tissue to capture the time varying strain field during the bubble growth, collapse, and subsequent generation of local shock wave. The relationships between the incident pressure, cavitation bubble dynamics, and induced deformation within a tissue surrogate during shock loading are investigated. In the next step, live brain tissue slices extracted from rats were tested with specified areas (e.g. Hippocampus) exposed to single bubble cavitation. Postmortem histological studies have been performed to quantify neuronal and astrocyte damage as a function of shock pressure. Our experiments have shown that the shock-induced cavitation bubble growth and collapse can be captured using this experimental facility and the results indicate that sensitive tissue damage indeed occurs due to the shock wave generated by cavitation bubble collapse.

Professor Subhash obtained his MS and PhD degrees from University of California San Diego and conducted post-doctoral research at California Institute of Technology, Pasadena, CA. He joined the faculty of Michigan Technological University (MTU) in 1993 and then moved to University of Florida (UF) in 2006. He has received numerous awards for excellence in teaching, research and professional service, including the ‘Significant Contribution Award’ American Nuclear Society – Materials Science and Technology Division (2014), Fellow of Society of Experimental Mechanics (2014) ‘Technology Innovator Award’ University of Florida (2014), UF Research Foundation Professor (2013), College of Engineering Teacher/Scholar of the year (2013), ‘2011 Researcher of the Year’ Mechanical and Aerospace Engineering Department, Second Place of the Best paper Awards at the 31st Annual American Ceramic Society meeting (2008), Michigan Tech Distinguished Research Award (2005), ASME Fellow (2004), ASME Student Section Advisor Award (2003), Society of Automotive Engineers (SAE) Ralph R. Teetor Educational Award (2000), American Society of Engineering Education (ASEE) Outstanding New Mechanics Educator Award(1996), and Distinguished Teaching Award at MTU (1994). He is an Associate Editor of Mechanics of Materials, Journal of the American Ceramic Society, Experimental Mechanics and ASME Journal of Engineering Materials and Technology. He has graduated 21 PhD students and is currently advising 12 PhD students in various fields related to processing, microstructural characterization and multiaxial behavior of advanced materials including ceramics, metals, composites, gels and brain tissue. He has authored around 150 peer reviewed journal papers and 70 conference proceedings. He has filed for 8 patent applications in various fields of material processing, mechanical testing, food packaging, and protective helmet design. His recent invention on fluid filled energy absorbing cushions for protective equipment has received widespread attention from major TV networks (Fox , CBS and 40 other local TV channels), and radio stations (including NPR) and articles by Reuters, ASEE morning bell and many local newspapers. He has given numerous invited lectures and seminars at many universities and international conferences.

ME-EM Graduate Seminar: Local Aggregation Characteristics and Visualization of Intermediate Layers during Evaporation of Nanofluid Droplets

oct23The ME-EM Graduate Seminar speaker on Thursday, October 23rd at 4:00 in 103 EERC will be Dr. Dong Hwan Shin a post doc in the Mechanical Engineering Department at Michigan Tech.

The title of his presentation will be ‘Local Aggregation Characteristics and Visualization of Intermediate Layers during Evaporation of Nanofluid Droplets’.

Recently, nanofluids (NF) are of substantial interest because of their potentials in exhibiting improved thermal performance. Thus, nanofluids are expected as the next generation of cooling fluids for automobiles and electronic devices. One of Dr. Shin’s research interests is about characterization of nanofluid droplet evaporation by using confocal and regular inverted microscopic systems. This presentation will introduce his recent work regarding the nanofluid droplet evaporation: Evaporation characteristics of nanofluid droplets with various volume fractions of 50 nm alumina (Al2O3) particles are experimentally examined. The effect of particle concentrations on droplet evaporation rates is examined. The corresponding wettability changes and the total evaporation time are also examined. Besides, he will also introduce the spatial non-uniformity of suspended nanoparticles in the droplet caused by the local aggregation visualized by using the inverted microscope system. The results show that the effective thermal conductivity should be changed according to the non-uniform distribution of nanoparticles inside a droplet on the surface. Next, the contact lines of nanofluids droplets during evaporation are visualized using a high-speed reflected mode slit-confocal. The present work deals with a challenging issue on the experimental visualization of the intermediate layer because the conventional optical approach cannot visualize this layer due to the optical limitation. The intermediate layer thickness varies with time during evaporation, which is observed based on the fringe pattern analysis. Those results show the feasibility of using fringe patterns of contact lines can provide instability of a contact-line region in the thin film and further explain heat and mass transfer in this region.

Dr. Dong Hwan (DH) Shin is a post-doctoral research scholar of Mechanical Engineering-Engineering Mechanics at Michigan Technological University. He received his B.S., M.S. and Ph.D in Mechanical Engineering in Chung-Ang University (CAU) in 2008, 2010 and 2014, respectively. He has already been to MTU as a visiting scholar three times in 2010, 2012 and 2013. His research interests are nanofluids and its applications, micro-droplet evaporation and its applications, flame spray and its applications, and computational fluid dynamics. He has published 17 journal papers and 22 proceedings.

ME-EM Graduate Seminar: Automotive Powertrain Control: Opportunities and Challenges

oct16The ME-EM Graduate Seminar speaker on Thursday, October 16 at 4:00 in 103 EERC
will be Dr. Chen-Fang Chang of GM Global Research & Development.

The title of his presentation will be ‘Automotive Powertrain Control: Opportunities and Challenges’.

Advanced powertrain systems are being introduced into passenger vehicles to meet regulatory and customer demands, simultaneously increasing fuel economy, reducing emissions and enhancing driveability. As the powertrain systems become more sophisticated, it will force a dramatic increase in control complexity and calibration effort. This presentation will detail the challenges facing automotive control community and the approaches a control engineer can take to confront these challenges. IC engine controls will be used to exemplify a whole engine controller development cycle. Future outlook will also be provided.

Dr. Chang is currently the Lab Group Manager of the Propulsion Control Systems Group at GM Global R&D. Since joining GM in 1994, he has worked on cylinder-pressure-based engine controls, diesel aftertreatment controls, HCCI engine controls, and, most recently, information-rich propulsion controls. Dr. Chang received his Ph.D. degree in Mechanical Engineering with minor in Electrical Engineering from Stanford University. He holds 43 US patents and has numerous technical publications. He is the recipient of 2013 ASME Rudolf Kalman Award and 2001 SAE Arch T. Coldwell Merit Award.

ME-EM Graduate Seminar: Space Tethers, Small Satellites, and System Engineering

oct9The ME-EM Graduate Seminar speaker on Thursday, October 9 at 4:00 in 103 EERC will be Dr. Nestor Voronka, Principal, M42 Technologies.

The title of his presentation will be ‘Space Tethers, Small Satellites, and System Engineering’.

This seminar will present an overview of space tether technology, its applications, and the
results of space tether missions to date. Space tethers present interesting system engineering challenges and in particular when integrated into small satellites. System engineering challenges
of both large and small spacecraft systems will be discussed along with some lessons learned and recommendations.

Dr. Nestor Voronka is the Principal of M42 Technologies, which develops, advanced technologies, provides alternative and relevant solutions to space and aerospace challenges and is currently focused on developing project solutions and flight systems for the DoD, NASA and commercial space customers. From 2003 to 2013 Mr. Voronka served as the Chief Technologist and VP of Tethers Unlimited, Inc where he led various product and technology development efforts designing space tether systems, nanosatellite components, propulsion systems, RF systems, spacecraft antennas, 3D printable radiation shielding, and UAV towed sensor systems. Mr. Voronka was the lead engineer responsible for the design, development, testing, and delivery, and operations of the MAST 3U CubeSat experiment that launched in April 2007. From 1996 to 2003, Mr. Voronka was Chief Engineer at Cybernet Systems Corp. where he was led the development of products and technologies in a number of areas including computer networking, force feedback devices, motor control, motion capture, machine vision, electro-optics, inertial navigation, aviation systems, and medical devices. While at the UM-Space Physics Research Lab 1991-1996 first as a student and then a staff engineer, Mr. Voronka worked the Tethered Satellite System (TSS-1R) that flew on the Space Shuttle Columbia STS-75 flight in February of 1996. Mr. Voronka has two Master’s degrees from the University of Michigan in Electrical Engineering in the areas of electromagnetics, and Signal/Image Processing.

ME-EM Graduate Seminar: Human-Centered Monitoring: From Enabling Technology, Human Factor to Computational Diagnosis

oct2The ME-EM Graduate Seminar speaker on Thursday, October 2 at 4:00 in 103 EERC will be Dr. Ye (Sarah) Sun from Michigan Tech Mechanical Engineering – Engineering Mechanics Department.

The title of her presentation will be ‘Human-Centered Monitoring: From Enabling Technology, Human Factor to Computational Diagnosis’.

The rapidly growing population ageing is a global phenomenon in the recent decades. The concomitant prevalence of chronic diseases necessitates proactive, human-centered approaches to reduce the high cost and enhance the biocompatibility and operability of the current healthcare systems. For drivers at all ages, drowsiness is one of the most prevalent root causes of accidents. Driver health and state monitoring provides an effective way to reduce the risk of driver related crashes. This study aims to facilitate the development of human-centered monitoring in healthcare and transportation safety. A comprehensive framework for human-centered monitoring has been developed that includes three major components, i.e., enabling technology, human factor and computational diagnosis. In the technology part, this study establishes a non-intrusive and non-contact interface platform for human health and state monitoring. Unlike the conventional clinical bio-potential measurement system, the platform is able to acquire the electrophysiological signals with a gap between the skin and the electrodes that is occupied by hair, cloth, and air. The non-contact platform avoids skin irritation and allergic contact dermatitis and is suitable for long-term monitoring purpose. To increase the flexibility in practical application, a body area network has also been integrated for different scenarios such as driving and home monitoring. The developed enabling technology was validated using simulated driving scenario, since it constitutes a high stress and high risk condition, especially for people with chronic diseases. For the human factor part, analyses were conducted on the physiological data collected from the drivers operating a high fidelity driving simulator. This involves driver state analyses particularly related to drowsiness and mental stress. The computational component involved the development of algorithms to assess the robustness of different physiological indicators for the extent of driver fatigue. Moreover, physiological signals for mental stress were also investigated which will serve as the technical basis for timely assistance.

Dr. Ye (Sarah) Sun is an assistant professor in the Department of
Mechanical Engineering-Engineering Mechanics at Michigan Technological
University. She received her Ph.D. degree in Electrical Engineering
from Case Western Reserve University. Her research is an
interdisciplinary resort that integrates engineering innovation with
human health and human behaviors. The primary focus is on
human-centered smart monitoring technologies that integrate advance
sensor technology and decision support to improve healthcare
and transportation safety.