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Faculty Publications

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Full-Text Articles in Engineering

Toward Building Resilient, Sustainable, And Smart Infrastructure In The 21st Century, Aly Mousaad Aly Nov 2018

Toward Building Resilient, Sustainable, And Smart Infrastructure In The 21st Century, Aly Mousaad Aly

Faculty Publications

In recent years, as a result of significant climate change, stringent windstorms are becoming more frequent than before. Given the threat that windstorms bring to people and property, wind/structural engineering research is imperative to improve the resilience of existing and new infrastructure, for community safety and assets protection. The Windstorm Impact, Science and Engineering (WISE) research program at Louisiana State University (LSU) focuses on creating new knowledge applicable to the mitigation of existing and new infrastructure, to survive and perform optimally under natural hazards. To achieve our research goals, we address two imperious challenges: (i) characterization of realistic wind ...


Development Of A Placement Exam To Increase Student Success In A Junior Level Circuits And Systems Class, David Parent Oct 2018

Development Of A Placement Exam To Increase Student Success In A Junior Level Circuits And Systems Class, David Parent

Faculty Publications

In this work, which is intended to be a Full Paper in the Innovative Practice Category, the implementation of an improved placement exam that increased the pass rate in a junior level systems course in the author’s electrical engineering department by 15% is presented. For almost 30 years the author’s EE department has used a face to face exam to place students in a junior level circuits and systems course or into a review workshop. The details of the exam and suggestions about future use in conjunction MyOpenMath analytics to increase student success are also given.


Integration Of An Electrical Engineering Capstone Course With Social Justice And Global Studies, David Parent, Patricia Backer Oct 2018

Integration Of An Electrical Engineering Capstone Course With Social Justice And Global Studies, David Parent, Patricia Backer

Faculty Publications

A four course package (six units total) consisting of two general education (GE) classes and two electrical engineering capstone classes that are taught in a highly integrated manner, that not only meets university GE requirements, but also meets the new ABET criteria in which the need to address a societal need is embedded with design criteria. The prompts for the new integrated GE/capstone Assessment results are also presented, along with methods to increase student motivation for studying GE.


Examination The Impact Of Various Factors On Student Success In An Introduction To Circuit Analysis Course, David Parent Oct 2018

Examination The Impact Of Various Factors On Student Success In An Introduction To Circuit Analysis Course, David Parent

Faculty Publications

In this work in progress, several models to predict student success in a sophomore introduction to circuit analysis class were created based on prior grade point average, grade in a pre-requisite physics class, the semester the pre-requisite physics class was taken, the number of units a student was taking, the number of times a student repeated the circuits class, and the number of times a student repeated any class prior to enrollment. While all models were statistically significant, the model that included prior GPA and the grade in a pre-requisite physics was the most significant for the data collection effort ...


Wireless Sensor Networks For Long-Term Monitoring Of Urban Noise, Courtney Peckens, Cédric Porter, Taylor Rink Sep 2018

Wireless Sensor Networks For Long-Term Monitoring Of Urban Noise, Courtney Peckens, Cédric Porter, Taylor Rink

Faculty Publications

Noise pollution in urban environments is becoming increasingly common and it has potential to negatively impact people’s health and decrease overall productivity. In order to alleviate these effects, it is important to better quantify noise patterns and levels through data collection and analysis. Wireless sensor networks offer a method for achieving this with a higher level of granularity than traditional handheld devices. In this study, a wireless sensing unit (WSU) was developed that possesses the same functionality as a handheld sound level meter. The WSU is comprised of a microcontroller unit that enables on-board computations, a wireless transceiver that ...


A Neuromorphic Quadratic, Integrate, And Fire Silicon Neuron With Adaptive Gain, David Parent, Eric Basham Jul 2018

A Neuromorphic Quadratic, Integrate, And Fire Silicon Neuron With Adaptive Gain, David Parent, Eric Basham

Faculty Publications

An integrated circuit implementation of a silicon neuron was designed, manufactured, and tested. The circuit was designed using the Quadratic, Integrate, and Fire (QIF) neuron model in 0.5 µm silicon technology. The neuron implementation was optimized for low current consumption, drawing only 1.56 mA per QIF circuit and utilized hysteretic reset, non-inverting integrator, and voltage-squarer circuits. The final area of each circuit in silicon was 268 µm height × 400 µm width. This design is the first IC of its kind for this neuron model and is successfully able to output true spiking that follows the behaviors of bistability ...


Identifying Prevalent Mathematical Pathways To Engineering In South Carolina, Eliza Gallagher, Christy Brown, D. Andrew Brown, Kristin Kelly Frady, Patrick Bass, Michael A. Matthews, Thomas T. Peters, Robert J. Rabb, Ikhalfani Solan, Ronald W. Welch, Anand K. Gramopadhye Jun 2018

Identifying Prevalent Mathematical Pathways To Engineering In South Carolina, Eliza Gallagher, Christy Brown, D. Andrew Brown, Kristin Kelly Frady, Patrick Bass, Michael A. Matthews, Thomas T. Peters, Robert J. Rabb, Ikhalfani Solan, Ronald W. Welch, Anand K. Gramopadhye

Faculty Publications

National data indicate that initial mathematics course placement in college is a strong predictor of persistence to degree in engineering, with students placed in calculus persisting at nearly twice the rate of those placed below calculus. Within the state of South Carolina, approximately 95% of engineering-intending students who initially place below calculus are from in-state. In order to make systemic change, we are first analyzing system-wide data to identify prevalent educational pathways within the state, and the mathematical milestones along those pathways taken by students in engineering and engineering-related fields. This paper reports preliminary analysis of that data to understand ...


Enabling Autonomous Navigation For Affordable Scooters, Kaikai Liu, Rajathswaroop Mulky Jun 2018

Enabling Autonomous Navigation For Affordable Scooters, Kaikai Liu, Rajathswaroop Mulky

Faculty Publications

Despite the technical success of existing assistive technologies, for example, electric wheelchairs and scooters, they are still far from effective enough in helping those in need navigate to their destinations in a hassle-free manner. In this paper, we propose to improve the safety and autonomy of navigation by designing a cutting-edge autonomous scooter, thus allowing people with mobility challenges to ambulate independently and safely in possibly unfamiliar surroundings. We focus on indoor navigation scenarios for the autonomous scooter where the current location, maps, and nearby obstacles are unknown. To achieve semi-LiDAR functionality, we leverage the gyros-based pose data to compensate ...


Impact Of First-Year Initiatives On Retention Of Students: Are There Differences In Retention Of Students By Ethnicity And Gender?, Patricia Backer, Joseph Green, Bryan Matlen, Cindy Kato Apr 2018

Impact Of First-Year Initiatives On Retention Of Students: Are There Differences In Retention Of Students By Ethnicity And Gender?, Patricia Backer, Joseph Green, Bryan Matlen, Cindy Kato

Faculty Publications

Project Succeed is a campus-wide initiative funded by the U.S. Department of Education. Its focus is to improve the 5-year graduation and retention rates and close the achievement gap for Under-Represented Minorities (URMs) across all majors at San José State University (SJSU). In addition, SJSU has a high percent of first generation students. We have several thrusts under this project: block scheduling, Faculty/Staff Mentor program, expanding Peer Educators, developing a First Year Experience Program, and developing more student living learning communities. This project is in its fourth year and we have analyzed each project effort with respect to ...


Natural Sensations Evoked In Distal Extremities Using Surface Electrical Stimulation, Julia P. Slopsema, John M. Boss, Lane A. Heyboer, Carson M. Tobias, Brooke P. Draggoo, Kathleen E. Finn, Payton J. Hoff, Katharine H. Polasek Jan 2018

Natural Sensations Evoked In Distal Extremities Using Surface Electrical Stimulation, Julia P. Slopsema, John M. Boss, Lane A. Heyboer, Carson M. Tobias, Brooke P. Draggoo, Kathleen E. Finn, Payton J. Hoff, Katharine H. Polasek

Faculty Publications

Background: Electrical stimulation is increasingly relevant in a variety of medical treatments. In this study, surface electrical stimulation was evaluated as a method to non-invasively target a neural function, specifically natural sensation in the distal limbs.

Method: Electrodes were placed over the median and ulnar nerves at the elbow and the common peroneal and lateral sural cutaneous nerves at the knee. Strength-duration curves for sensation were compared between nerves. The location, modality, and intensity of each sensation were also analyzed. In an effort to evoke natural sensations, several patterned waveforms were evaluated.

Results: Distal sensation was obtained in all but ...


Development And Field Testing Of An Interactive Transit Station Information System (Itsis) Using Connected Vehicle Technologies, Huadong Meng, Jacob Tsao, Kun Zhou, Justin Picar, Bradley Mizuno, Wei-Bin Zhang Dec 2017

Development And Field Testing Of An Interactive Transit Station Information System (Itsis) Using Connected Vehicle Technologies, Huadong Meng, Jacob Tsao, Kun Zhou, Justin Picar, Bradley Mizuno, Wei-Bin Zhang

Faculty Publications

The objective of Interactive Transit Station Information System (ITSIS) is to better inform transit travelers during their trips and to enable dynamic transit operations to better serve travelers. The ultimate goal is to make transit more friendly and attractive to the traveling population such that transit will become a viable choice for travel and an integrated part of the solution for congestion relief. This report documents a research effort to develop and test a ITSIS prototype that uses Connected Vehicle technologies to enable the real-time interaction between passengers and transit systems at bus stations. The reports summarizes the findings from ...


Formal Performance Guarantees For An Approach To Human In The Loop Robot Missions, Damian Lyons, Ron Arkin, Shu Jiang, Matt O'Brien, Feng Tang, Peng Tang Oct 2017

Formal Performance Guarantees For An Approach To Human In The Loop Robot Missions, Damian Lyons, Ron Arkin, Shu Jiang, Matt O'Brien, Feng Tang, Peng Tang

Faculty Publications

Abstract— A key challenge in the automatic verification of robot mission software, especially critical mission software, is to be able to effectively model the performance of a human operator and factor that into the formal performance guarantees for the mission. We present a novel approach to modelling the skill level of the operator and integrating it into automatic verification using a linear Gaussians model parameterized by experimental calibration. Our approach allows us to model different skill levels directly in terms of the behavior of the lumped, robot plus operator, system.

Using MissionLab and VIPARS (a behavior-based robot mission verification module ...


Spin-Imbalance In A 2d Fermi-Hubbard System, Peter Brown, Debayan Mitra, Elmer Guardado-Sanchez, Peter Schauß, Stanimir Kondov, Ehsan Khatami, Thereza Paiva, Nandini Trivedi, David Huse, Waseem Bakr Sep 2017

Spin-Imbalance In A 2d Fermi-Hubbard System, Peter Brown, Debayan Mitra, Elmer Guardado-Sanchez, Peter Schauß, Stanimir Kondov, Ehsan Khatami, Thereza Paiva, Nandini Trivedi, David Huse, Waseem Bakr

Faculty Publications

The interplay of strong interactions and magnetic fields gives rise to unusual forms of superconductivity and magnetism in quantum many-body systems. Here, we present an experimental study of the two-dimensional Fermi-Hubbard model—a paradigm for strongly correlated fermions on a lattice—in the presence of a Zeeman field and varying doping. Using site-resolved measurements, we revealed anisotropic antiferromagnetic correlations, a precursor to long-range canted order. We observed nonmonotonic behavior of the local polarization with doping for strong interactions, which we attribute to the evolution from an antiferromagnetic insulator to a metallic phase. Our results pave the way to experimentally mapping ...


Examining Accident Reports Involving Autonomous Vehicles In California, Francesca Favaro, Nazanin Nader, Sky Eurich, Michelle Tripp, Naresh Varadaraju Sep 2017

Examining Accident Reports Involving Autonomous Vehicles In California, Francesca Favaro, Nazanin Nader, Sky Eurich, Michelle Tripp, Naresh Varadaraju

Faculty Publications

Autonomous Vehicle technology is quickly expanding its market and has found in Silicon Valley, California, a strong foothold for preliminary testing on public roads. In an effort to promote safety and transparency to consumers, the California Department of Motor Vehicles has mandated that reports of accidents involving autonomous vehicles be drafted and made available to the public. The present work shows an in-depth analysis of the accident reports filed by different manufacturers that are testing autonomous vehicles in California (testing data from September 2014 to March 2017). The data provides important information on autonomous vehicles accidents’ dynamics, related to the ...


Effect Of Cohorts On Student Retention In Engineering, Patricia Backer, Cindy Kato Jun 2017

Effect Of Cohorts On Student Retention In Engineering, Patricia Backer, Cindy Kato

Faculty Publications

Project Succeed is a campus-wide initiative funded by the U.S. Department of Education. Its focus is to improve the 5-year graduation and retention rates and close the achievement gap for Under-Represented Minorities (URMs) across all majors at San José State University (SJSU). There are three major goals: strengthen SJSU’s core academic performance in retention and graduation; provide an improved supportive environment for URM students; and enhance the delivery and integration of academic and co-curricular support services. For Fall 2015, newly matriculated students in the College of Business, College of Engineering, and Child and Adolescent Development Department (CHAD) were ...


An Approach To Robust Homing With Stereovision, Fuqiang Fu, Damian Lyons Apr 2017

An Approach To Robust Homing With Stereovision, Fuqiang Fu, Damian Lyons

Faculty Publications

Visual Homing is a bioinspired approach to robot navigation which can be fast and uses few assumptions. However, visual homing in a cluttered and unstructured outdoor environment offers several challenges to homing methods that have been developed for primarily indoor environments. One issue is that any current image during homing may be tilted with respect to the home image. The second is that moving through a cluttered scene during homing may cause obstacles to interfere between the home scene and location and the current scene and location. In this paper, we introduce a robust method to improve a previous developed ...


Biotemplating Pores With Size And Shape Diversity For Li-Oxygen Battery Cathodes, Dahyun Oh, Cagla Ozgit-Akgun, Esin Akca, Leslie Thompson, Loza Tadesse, Ho-Cheol Kim, Gökhan Demirci, Robert Miller Apr 2017

Biotemplating Pores With Size And Shape Diversity For Li-Oxygen Battery Cathodes, Dahyun Oh, Cagla Ozgit-Akgun, Esin Akca, Leslie Thompson, Loza Tadesse, Ho-Cheol Kim, Gökhan Demirci, Robert Miller

Faculty Publications

Synthetic porogens provide an easy way to create porous structures, but their usage is limited due to synthetic difficulties, process complexities and prohibitive costs. Here we investigate the use of bacteria, sustainable and naturally abundant materials, as a pore template. The bacteria require no chemical synthesis, come in variable sizes and shapes, degrade easier and are approximately a million times cheaper than conventional porogens. We fabricate free standing porous multiwalled carbon nanotube (MWCNT) films using cultured, harmless bacteria as porogens, and demonstrate substantial Li-oxygen battery performance improvement by porosity control. Pore volume as well as shape in the cathodes were ...


Multi-Valued Sequences Generated By Power Residue Symbols Over Odd Characteristic Fields, Begum Nasima, Yasuyuki Nogami, Satoshi Uehara, Robert Morelos-Zaragoza Apr 2017

Multi-Valued Sequences Generated By Power Residue Symbols Over Odd Characteristic Fields, Begum Nasima, Yasuyuki Nogami, Satoshi Uehara, Robert Morelos-Zaragoza

Faculty Publications

This paper proposes a new approach for generating pseudo random multi-valued (including binary-valued) sequences. The approach uses a primitive polynomial over an odd characteristic prime field $\f{p}$, where p is an odd prime number. Then, for the maximum length sequence of vectors generated by the primitive polynomial, the trace function is used for mapping these vectors to scalars as elements in the prime field. Power residue symbol (Legendre symbol in binary case) is applied to translate the scalars to k-value scalars, where k is a prime factor of p-1. Finally, a pseudo random k-value sequence is obtained. Some important ...


Performance Verification For Robot Missions In Uncertain Environments, Damian Lyons, Ron Arkin, Shu Jiang, Matt O'Brien, Feng Tang, Peng Tang Jan 2017

Performance Verification For Robot Missions In Uncertain Environments, Damian Lyons, Ron Arkin, Shu Jiang, Matt O'Brien, Feng Tang, Peng Tang

Faculty Publications

Abstract—Certain robot missions need to perform predictably in a physical environment that may have significant uncertainty. One approach is to leverage automatic software verification techniques to establish a performance guarantee. The addition of an environment model and uncertainty in both program and environment, however, means the state-space of a model-checking solution to the problem can be prohibitively large. An approach based on behavior-based controllers in a process-algebra framework that avoids state-space combinatorics is presented here. In this approach, verification of the robot program in the uncertain environment is reduced to a filtering problem for a Bayesian Network. Validation results ...


Impact Of Reviewer Social Interaction On Online Consumer Review Fraud Detection, Kunal Goswami, Younghee Park, Chungsik Song Jan 2017

Impact Of Reviewer Social Interaction On Online Consumer Review Fraud Detection, Kunal Goswami, Younghee Park, Chungsik Song

Faculty Publications

Background Online consumer reviews have become a baseline for new consumers to try out a business or a new product. The reviews provide a quick look into the application and experience of the business/product and market it to new customers. However, some businesses or reviewers use these reviews to spread fake information about the business/product. The fake information can be used to promote a relatively average product/business or can be used to malign their competition. This activity is known as reviewer fraud or opinion spam. The paper proposes a feature set, capturing the user social interaction behavior ...


Robust And Agile System Against Fault And Anomaly Traffic In Software Defined Networks, Mihui Kim, Younghee Park, Rohit Kotalwar Jan 2017

Robust And Agile System Against Fault And Anomaly Traffic In Software Defined Networks, Mihui Kim, Younghee Park, Rohit Kotalwar

Faculty Publications

The main advantage of software defined networking (SDN) is that it allows intelligent control and management of networking though programmability in real time. It enables efficient utilization of network resources through traffic engineering, and offers potential attack defense methods when abnormalities arise. However, previous studies have only identified individual solutions for respective problems, instead of finding a more global solution in real time that is capable of addressing multiple situations in network status. To cover diverse network conditions, this paper presents a comprehensive reactive system for simultaneously monitoring failures, anomalies, and attacks for high availability and reliability. We design three ...


A Multi-Value Sequence Generated By Power Residue Symbol And Trace Function Over Odd Characteristic Field, Yasuyuki Nogami, Satoshi Uehara, Kazuyoshi Tsuchiya, Nasima Begum, Hiroto Ino, Robert Morelos-Zaragoza Dec 2016

A Multi-Value Sequence Generated By Power Residue Symbol And Trace Function Over Odd Characteristic Field, Yasuyuki Nogami, Satoshi Uehara, Kazuyoshi Tsuchiya, Nasima Begum, Hiroto Ino, Robert Morelos-Zaragoza

Faculty Publications

This paper proposes a new multi-value sequence generated by utilizing primitive element, trace, and power residue symbol over odd characteristic finite field. In detail, let p and k be an odd prime number as the characteristic and a prime factor of p-1, respectively. Our proposal generates k-value sequence T={ti | ti=fk(Tr(ωi)+A)}, where ω is a primitive element in the extension field $\F{p}{m}$, Tr(⋅) is the trace function that maps $\F{p}{m} \rightarrow \f{p}$, A is a non-zero scalar in the prime field $\f{p}$, and fk(⋅) is a certain mapping function based ...


Wind Power: Frustrating Yet Inevitable, Garth Woodruff Nov 2016

Wind Power: Frustrating Yet Inevitable, Garth Woodruff

Faculty Publications

No abstract provided.


Measuring Vapor Intrusion: From Source Science Politics To A Transdisciplinary Approach, Peter C. Little, Kelly G. Pennell Oct 2016

Measuring Vapor Intrusion: From Source Science Politics To A Transdisciplinary Approach, Peter C. Little, Kelly G. Pennell

Faculty Publications

Investigation of indoor air quality has been on the upswing in recent years. In this article, we focus on how the transport of subsurface vapors into indoor air spaces, a process known as ‘vapor intrusion’, (VI) is defined and addressed. For environmental engineers and physical scientists who specialize in this emerging indoor environmental exposure science, VI is notoriously difficult to characterize, leading the regulatory community to seek improved science-based understandings of VI pathways and exposures. Yet despite the recent growth in VI science and competition between environmental consulting companies, VI studies have largely overlooked the social and political field in ...


Investigation Of Shadowing Effects In Typical Propagation Scenarios For High Speed Railway At 2350 Mhz, Liu Liu, Cheng Tao, David W. Matolak, Tao Zhou, Houjin Chen Sep 2016

Investigation Of Shadowing Effects In Typical Propagation Scenarios For High Speed Railway At 2350 Mhz, Liu Liu, Cheng Tao, David W. Matolak, Tao Zhou, Houjin Chen

Faculty Publications

Based on realistic measurements in China, shadowing characteristics at the frequency of 2350 MHz were investigated in typical High-Speed Railway environments. After confirming that the measured shadowing satisfies wide-sense stationarity (assessed via the reverse arrangement test method), we quantify the shadowing correlation. Three types of correlation models are compared for the shadowing characterization, and the Normalized Mean Square Error is used to determine the best matching model: a single decaying exponential function. Decorrelation distances were found to be 11.9 m, 17.7 m, and 8.3 m in our three HSR scenarios, respectively. The results should be useful for ...


Using The Gauge Condition To Simplify The Elastodynamic Analysis Of Guided Wave Propagation, Bhuiyan Yeasin Md, Victor Giurgiutiu Sep 2016

Using The Gauge Condition To Simplify The Elastodynamic Analysis Of Guided Wave Propagation, Bhuiyan Yeasin Md, Victor Giurgiutiu

Faculty Publications

In this article, gauge condition in elastodynamics is explored more to revive its potential capability of simplifying wave propagation problems in elastic medium. The inception of gauge condition in elastodynamics happens from the Navier-Lame equations upon application of Helmholtz theorem. In order to solve the elastic wave problems by potential function approach, the gauge condition provides the necessary conditions for the potential functions. The gauge condition may be considered as the superposition of the separate gauge conditions of Lamb waves and shear horizontal (SH) guided waves respectively, and thus, it may be resolved into corresponding gauges of Lamb waves and ...


Imaging Right Ventricular Function To Predict Outcome In Pulmonary Arterial Hypertension, Alessandro Bellofiore, Melanie Brewis, Rebecca Vanderpool, Naomi Chesler, Martin Johnson, Robert Naeije, Andrew Peacock Sep 2016

Imaging Right Ventricular Function To Predict Outcome In Pulmonary Arterial Hypertension, Alessandro Bellofiore, Melanie Brewis, Rebecca Vanderpool, Naomi Chesler, Martin Johnson, Robert Naeije, Andrew Peacock

Faculty Publications

Right ventricular (RV) function is a major determinant of outcome in pulmonary arterial hypertension (PAH). However, uncertainty persists about the optimal method of evaluation.MethodsWe measured RV end-systolic and end-diastolic volumes (ESV and EDV) using cardiac magnetic resonance imaging and RV pressures during right heart catheterization in 140 incident PAH patients and 22 controls. A maximum RV pressure (Pmax) was calculated from the nonlinear extrapolations of early and late systolic portions of the RV pressure curve. The gold standard measure of RV function adaptation to afterload, or RV–arterial coupling (Ees/Ea) was estimated by the stroke volume (SV)/ESV ...


Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff Aug 2016

Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff

Faculty Publications

No abstract provided.


Toward Risk Assessment 2.0: Safety Supervisory Control And Model-Based Hazard Monitoring For Risk-Informed Safety Interventions, Francesca Favaro, Joseph Saleh Aug 2016

Toward Risk Assessment 2.0: Safety Supervisory Control And Model-Based Hazard Monitoring For Risk-Informed Safety Interventions, Francesca Favaro, Joseph Saleh

Faculty Publications

Probabilistic Risk Assessment (PRA) is a staple in the engineering risk community, and it has become to some extent synonymous with the entire quantitative risk assessment undertaking. Limitations of PRA continue to occupy researchers, and workarounds are often proposed. After a brief review of this literature, we propose to address some of PRA׳s limitations by developing a novel framework and analytical tools for model-based system safety, or safety supervisory control, to guide safety interventions and support a dynamic approach to risk assessment and accident prevention. Our work shifts the emphasis from the pervading probabilistic mindset in risk assessment toward ...


Guided Wave Based Crack Detection In The Rivet Hole Using Global Analytical With Local Fem Approach, Bhuiyan Yeasin Md, Yanfeng Shen, Victor Giurgiutiu Jul 2016

Guided Wave Based Crack Detection In The Rivet Hole Using Global Analytical With Local Fem Approach, Bhuiyan Yeasin Md, Yanfeng Shen, Victor Giurgiutiu

Faculty Publications

In this article, ultrasonic guided wave propagation and interaction with the rivet hole cracks has been formulated using closed-form analytical solution while the local damage interaction, scattering, and mode conversion have been obtained from finite element analysis. The rivet hole cracks (damage) in the plate structure gives rise to the non-axisymmetric scattering of Lamb wave, as well as shear horizontal (SH) wave, although the incident Lamb wave source (primary source) is axisymmetric. The damage in the plate acts as a non-axisymmetric secondary source of Lamb wave and SH wave. The scattering of Lamb and SH waves are captured using wave ...