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Quantitative Characterization Of Complex Systems—An Information Theoretic Approach, Aditya Akundi, Eric Smith Dec 2021

Quantitative Characterization Of Complex Systems—An Information Theoretic Approach, Aditya Akundi, Eric Smith

Manufacturing & Industrial Engineering Faculty Publications and Presentations

A significant increase in System-of-Systems (SoS) is currently observed in the social and technical domains. As a result of the increasing number of constituent system components, Systems of Systems are becoming larger and more complex. Recent research efforts have highlighted the importance of identifying innovative statistical and theoretical approaches for analyzing complex systems to better understand how they work. This paper portrays the use of an agnostic twostage examination structure for complex systems aimed towards developing an information theorybased approach to analyze complex technical and socio-technical systems. Towards the goal of characterizing system complexity with information entropy, work was carried …


Force And Torque Model Sensitivity And Coarse Graining For Bedload-Dominated Sediment Transport, Liheng Guan, Jorge Salinas, ‪Nadim Zgheib, S. Balachandar Dec 2021

Force And Torque Model Sensitivity And Coarse Graining For Bedload-Dominated Sediment Transport, Liheng Guan, Jorge Salinas, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications and Presentations

We present results from Euler–Lagrange simulations of turbulent flow over an erodible monodisperse bed of particles at a shear Reynolds number of R e τ = 180 . The Galileo number G a and the ratio of Shields to the critical Shields number Θ / θ c r were varied in the range 11.4 to 29.8 and 1.32 to 5.98, respectively. Two drag force models were investigated along with the influence of lift, particle rotation, and tangential collision forces for each model. Both models give similar results as far as mean particle flux and Shields stress are concerned, however we …


Drug-Based Therapeutic Strategies For Covid-19-Infected Patients And Their Challenges, Khatereh Zarkesh, Elaheh Entezar-Almahdi, Parisa Ghasemiyeh, Mohsen Akbarian, Marzieh Bahmani, Shahrzad Roudaki, Rahil Fazlinejad, Soliman Mohammadi-Samani, Negar Firouzabadi, Majid Hosseini, Fatemeh Farjadian Nov 2021

Drug-Based Therapeutic Strategies For Covid-19-Infected Patients And Their Challenges, Khatereh Zarkesh, Elaheh Entezar-Almahdi, Parisa Ghasemiyeh, Mohsen Akbarian, Marzieh Bahmani, Shahrzad Roudaki, Rahil Fazlinejad, Soliman Mohammadi-Samani, Negar Firouzabadi, Majid Hosseini, Fatemeh Farjadian

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Emerging epidemic-prone diseases have introduced numerous health and economic challenges in recent years. Given current knowledge of COVID-19, herd immunity through vaccines alone is unlikely. In addition, vaccination of the global population is an ongoing challenge. Besides, the questions regarding the prevalence and the timing of immunization are still under investigation. Therefore, medical treatment remains essential in the management of COVID-19. Herein, recent advances from beginning observations of COVID-19 outbreak to an understanding of the essential factors contributing to the spread and transmission of COVID-19 and its treatment are reviewed. Furthermore, an in-depth discussion on the epidemiological aspects, clinical symptoms …


Subharmonic Resonance Of One Fourth Order Of Electrostatically Actuated Mems Circular Plates: Amplitude-Frequency Response, Dumitru Caruntu, Julio Beatriz, Miguel Martinez Nov 2021

Subharmonic Resonance Of One Fourth Order Of Electrostatically Actuated Mems Circular Plates: Amplitude-Frequency Response, Dumitru Caruntu, Julio Beatriz, Miguel Martinez

Mechanical Engineering Faculty Publications and Presentations

This work deals with the amplitude-frequency response subharmonic resonance of 1/4 order of electrostatically actuated circular plates. The method of multiple scales is used to model the hard excitations and to predict the response. This work predicts that the steady state solutions are zero amplitude solutions, and non-zero amplitude solutions which consist of stable and unstable branches. The effects of parameters such as voltage and damping on the response are predicted. As the voltage increases, the non-zero amplitude solutions are shifted to lower frequencies. As the damping increases, the non-zero steady-state amplitudes are shifted to higher amplitudes, so larger initial …


A Framework Of Dynamic Data Driven Digital Twin For Complex Engineering Products: The Example Of Aircraft Engine Health Management, Zhenhua Wu, Jianzhi Li Nov 2021

A Framework Of Dynamic Data Driven Digital Twin For Complex Engineering Products: The Example Of Aircraft Engine Health Management, Zhenhua Wu, Jianzhi Li

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Digital twin is a vital enabling technology for smart manufacturing in the era of Industry 4.0. Digital twin effectively replicates its physical asset enabling easy visualization, smart decision-making and cognitive capability in the system. In this paper, a framework of dynamic data driven digital twin for complex engineering products was proposed. To illustrate the proposed framework, an example of health management on aircraft engines was studied. This framework models the digital twin by extracting information from the various sensors and Industry Internet of Things (IIoT) monitoring the remaining useful life (RUL) of an engine in both cyber and physical domains. …


Forcespun Polyvinylpyrrolidone/Copper And Polyethylene Oxide/Copper Composite Fibers And Their Use As Antibacterial Agents, Md Toukir Hasan, Ramiro Gonzalez, Ari Alexis Munoz, Luis Materon, Jason Parsons, Mataz Alcoutlabi Oct 2021

Forcespun Polyvinylpyrrolidone/Copper And Polyethylene Oxide/Copper Composite Fibers And Their Use As Antibacterial Agents, Md Toukir Hasan, Ramiro Gonzalez, Ari Alexis Munoz, Luis Materon, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

Copper nanoparticles (CuNPs) embedded in polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO) fiber-matrices were prepared through centrifugal spinning of PVP/ethanol and PEO/aqueous solutions, respectively. The prime focus of the current study is to investigate the antibacterial activity of composite fibers against Escherichia coli (E. coli) and Bacillus cereus (B. cereus) bacteria. During the fiber formation, the centrifugal spinning parameters such as spinneret rotational speed, spinneret to collector distance, and relative humidity were carefully chosen to obtain long and continuous fibers. The structural and morphological analyses of both composite fibers were investigated using scanning electron microscopy, X-ray diffraction, …


Optimal Tracking In Switched Systems With Free Final Time And Fixed Mode Sequence Using Approximate Dynamic Programming, Tohid Sardarmehni, Xingyong Song Oct 2021

Optimal Tracking In Switched Systems With Free Final Time And Fixed Mode Sequence Using Approximate Dynamic Programming, Tohid Sardarmehni, Xingyong Song

Mechanical Engineering Faculty Publications and Presentations

Optimal tracking in switched systems with fixed mode sequence and free final time is studied in this article. In the optimal control problem formulation, the switching times and the final time are treated as parameters. For solving the optimal control problem, approximate dynamic programming (ADP) is used. The ADP solution uses an inner loop to converge to the optimal policy at each time step. In order to decrease the computational burden of the solution, a new method is introduced, which uses evolving suboptimal policies (not the optimal policies), to learn the optimal solution. The effectiveness of the proposed solutions is …


Numerical Study Of Fully Coupled Fluid-Structure Interaction Of Stented Ureter By Varying The Stent Side-Holes, Erick Martinez, Ben Xu, Jianzhi Li, Yingchen Yang Oct 2021

Numerical Study Of Fully Coupled Fluid-Structure Interaction Of Stented Ureter By Varying The Stent Side-Holes, Erick Martinez, Ben Xu, Jianzhi Li, Yingchen Yang

Mechanical Engineering Faculty Publications and Presentations

Ureteral stents are a measure used for many medical issues involving urology, such as kidney stones or kidney transplants. The purpose of applying stents is to help relieve the urine flow while the ureter is either blocked or trying to close itself, which creates blockages. These ureteral stents, while necessary, cause pain and discomfort to patients due to them being a solid that moves around inside the patients’ body. The ureter normally moves urine to the bladder through peristaltic forces. Due to the ureter being a hyperelastic material, these peristaltic forces cause the ureter to deform easily, making it necessary …


Centrifugal Spinning And Characterization Of Co3o4 Coated Carbon Fibers, J. Ayala, D. Ramirez, Elizabeth M. Fletes, Helia Magali Morales, Jason Parsons, Mataz Alcoutlabi Oct 2021

Centrifugal Spinning And Characterization Of Co3o4 Coated Carbon Fibers, J. Ayala, D. Ramirez, Elizabeth M. Fletes, Helia Magali Morales, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications and Presentations

Centrifugally spun polyacrylonitrile (PAN) microfibers surface-coated with Co3O4 nanoparticles (NPs) were prepared as precursors to produce coated Co3O4 carbon-composite fibers. The Co3O4/C composite fibers were obtained through a staged heating process during which the Co3O4PAN precursor fibers were stabilized over four hours at 200 °C, and subsequently the stabilized fibers were carbonized for six hours at 600 °C. The synthesis process presented in this work provides an effective strategy for the fabrication of surface coated-fiber materials, including composite fibers with good structure and morphology. The characterization of the Co3O4/C composite fibers was performed using SEM, EDS, XPS, XRD …


Piezoelectric Properties Of Pvdf-Zn2geo4 Fine Fiber Mats, Fariha Rubaiya, Swati Mohan, Bhupendra B. Srivastava, Horacio Vasquez, Karen Lozano Sep 2021

Piezoelectric Properties Of Pvdf-Zn2geo4 Fine Fiber Mats, Fariha Rubaiya, Swati Mohan, Bhupendra B. Srivastava, Horacio Vasquez, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

The current paper presents the development and characterization of polyvinylidene fluoride (PVDF)-Zn2GeO4 (ZGO) fine fiber mats. ZGO nanorods (NRs) were synthesized using a hydrothermal method and incorporated in a PVDF solution to produce fine fiber mats. The fiber mats were prepared by varying the concentration of ZGO NRs (1.25–10 wt %) using the Forcespinning® method. The developed mats showed long, continuous, and homogeneous fibers, with average fiber diameters varying from 0.7 to 1 µm, depending on the ZGO concentration. X-ray diffraction spectra depicted a positive correlation among concentration of ZGO NRs and strengthening of the beta …


Micro Scalable Graphene Oxide Productions Using Controlled Parameters In Bench Reactor, Carolina S. Andrade, Anna Paula Godoy, Marcos Antônio Gimenes Benega, Ricardo J. E. Andrade, Rafael Cardoso Andrade, Wellington Marcos Silva, Josué Marciano De Oliveira Cremonezzi, Waldemar Augusto De Almeida Macedo, Hélio Ribeiro, Jaime Taha-Tijerina Aug 2021

Micro Scalable Graphene Oxide Productions Using Controlled Parameters In Bench Reactor, Carolina S. Andrade, Anna Paula Godoy, Marcos Antônio Gimenes Benega, Ricardo J. E. Andrade, Rafael Cardoso Andrade, Wellington Marcos Silva, Josué Marciano De Oliveira Cremonezzi, Waldemar Augusto De Almeida Macedo, Hélio Ribeiro, Jaime Taha-Tijerina

Manufacturing & Industrial Engineering Faculty Publications and Presentations

The detailed study of graphene oxide (GO) synthesis by changing the graphite/oxidizing reagents mass ratios (mG/mROxi), provided GO nanosheets production with good yield, structural quality, and process savings. Three initial samples containing different amounts of graphite (3.0 g, 4.5 g, and 6.0 g) were produced using a bench reactor under strictly controlled conditions to guarantee the process reproducibility. The produced samples were analyzed by Raman spectroscopy, atomic force microscopy (AFM), x-ray diffraction (XDR), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR) and thermogravimetry (TGA) techniques. The results showed that the major GO product comprised of nanosheets containing between 1–5 layers, …


Embedded Curriculum With Industry-Recognized Certifications To Improve The Marketability Of Engineering Technology Graduates, Immanuel Edinbarough, Jesus A. Gonzalez-Rodriguez Jul 2021

Embedded Curriculum With Industry-Recognized Certifications To Improve The Marketability Of Engineering Technology Graduates, Immanuel Edinbarough, Jesus A. Gonzalez-Rodriguez

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Embedded Curriculum with Industry Recognized Certifications to Improve the Marketability of Engineering Technology Graduates

The Fourth Industrial Revolution is challenging the industries to change the way they manage and operate the manufacturing environment. This leads to the transformation of the world through artificial intelligence, next-generation robotics, automation, big data analytics, 5G technology and Internet of Things. This idea of Industry 4.0 forces the change in the industries of today and tomorrow. In this, cyber physical systems communicate with one another using the Internet of Things. The manufacturing sector takes full advantage of these technologies to produce innovative products to enhance …


Incorporating A Mid-Semester Project To Evaluate Communication, And Leadership Skills For Undergraduate Engineering Students In The Statics/Strength Of Materials Course: A Comparative Assessment Before And During Covid-19, Eleazar Marquez, Samuel Garcia Jul 2021

Incorporating A Mid-Semester Project To Evaluate Communication, And Leadership Skills For Undergraduate Engineering Students In The Statics/Strength Of Materials Course: A Comparative Assessment Before And During Covid-19, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications and Presentations

In this research study, a Popsicle-bridge project was assigned to a cohort of undergraduate engineering students enrolled in a Statics and Strength of Materials Course to enhance technical, communication, and leadership skills when working in a group setting. In most undergraduate engineering courses, the technical content is primarily emphasized for the academic development of the student. However, a practicing engineer must be able to possess and apply communication and leadership skills, which are often excluded from the existing curriculum. The first assessment of this project was completed with a cohort of 85 students in the Fall of 2019 before the …


Study Of Friction And Wear Effects In Aluminum Parts Manufactured Via Single Point Incremental Forming Process Using Petroleum And Vegetable Oil-Based Lubricants, Jose M. Diabb Zavala, Oscar Martinez-Romero, Alex Elias-Zuniga, Hector Manuel Leija Gutierrez, Alejandro Estrada-De La Vega, Jaime Taha-Tijerina Jul 2021

Study Of Friction And Wear Effects In Aluminum Parts Manufactured Via Single Point Incremental Forming Process Using Petroleum And Vegetable Oil-Based Lubricants, Jose M. Diabb Zavala, Oscar Martinez-Romero, Alex Elias-Zuniga, Hector Manuel Leija Gutierrez, Alejandro Estrada-De La Vega, Jaime Taha-Tijerina

Manufacturing & Industrial Engineering Faculty Publications and Presentations

This paper focuses on studying how mineral oil, sunflower, soybean, and corn lubricants influence friction and wear effects during the manufacturing of aluminum parts via the single point incremental forming (SPIF) process. To identify how friction, surface roughness, and wear change during the SPIF of aluminum parts, Stribeck curves were plotted as a function of the SPIF process parameters such as vertical step size, wall angle, and tool tip semi-spherical diameter. Furthermore, lubricant effects on the surface of the formed parts are examined by energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM) images, the Alicona optical 3D measurement system, …


Reshaping The Landscape Of The Future: Software-Defined Manufacturing, Lei Xu, Lin Chen, Zhimin Gao, Hiram Moya, Weidong Shi Jul 2021

Reshaping The Landscape Of The Future: Software-Defined Manufacturing, Lei Xu, Lin Chen, Zhimin Gao, Hiram Moya, Weidong Shi

Computer Science Faculty Publications and Presentations

We describe the concept of software-defined manufacturing, which divides the manufacturing ecosystem into software definition and physical manufacturing layers. Software-defined manufacturing allows better resource sharing and collaboration, and it has the potential to transform the existing manufacturing sector.


Printing Quality Improvement For Laser-Induced Forward Transfer Bioprinting: Numerical Modeling And Experimental Validation, Jie Qu, Chaoran Dou, Ben Xu, Jianzhi Li, Zhonghao Rao, Andrew Tsin Jul 2021

Printing Quality Improvement For Laser-Induced Forward Transfer Bioprinting: Numerical Modeling And Experimental Validation, Jie Qu, Chaoran Dou, Ben Xu, Jianzhi Li, Zhonghao Rao, Andrew Tsin

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Laser-induced-forward-transfer (LIFT)-based laser assisted bioprinting (LAB) has great advantages over other three-dimensional (3D) bioprinting techniques, such as none-contact, free of clogging, high precision, and good compatibility. In a typical LIFT based LAB process, a jet flow transfers the bioink from the ribbon to the substrate due to bioink bubble generation and collapse, and the printing quality is highly dependent on the jet flow regime (stable or unstable), so it is a great challenge to understand the connection between the jet flow and the printing outcomes. To tackle this challenge, a novel computational-fluid-dynamics (CFD)-based model was developed in this study to …


Scaffolding Student Success: Developing A Culturally Responsive Approach To Support Underrepresented Minorities In Engineering Undergraduate Research, Eleazar Marquez, Samuel Garcia Jul 2021

Scaffolding Student Success: Developing A Culturally Responsive Approach To Support Underrepresented Minorities In Engineering Undergraduate Research, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications and Presentations

In this research study, a scaffolding technique is implemented in undergraduate research to cultivate and enhance engineering related aptitudes and stimulate additional experience that will allow underrepresented minority students to fully engage in communication and leadership roles post-graduation. Developing and supporting the growth of underrepresented minorities as leaders who make significant innovative contributions to the global and interconnected scientific society requires awareness of contextual issues that shape their educational experiences and a commitment to enact on a framework that blends technical, communication, and leadership skills in undergraduate engineering education. In the context of this four year study, a total of …


Quality Mentorship Matters: An Innovative Approach To Supporting Student Success In Engineering Undergraduate Research, Eleazar Marquez, Samuel Garcia Jul 2021

Quality Mentorship Matters: An Innovative Approach To Supporting Student Success In Engineering Undergraduate Research, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications and Presentations

In this research study, the authors developed a new model of mentorship for faculty members to engage and support their group of students conducting undergraduate engineering research. Research efforts attest that mentoring undergraduate students is a critical role that can dramatically enhance student academic and personal outcomes. This finding is magnified in the context of STEM related disciplines, such as engineering, where efforts to pro-actively diversify the workforce are taking shape. Yet, not every form of faculty-student mentorship is proven to be effective, particularly when faculty conceal forms of knowledge and information regarding internship/employment resources, departmental and research opportunities, curriculum …


Investigation Of Theoretical Scaling Laws Using Large Eddy Simulations For Airborne Spreading Of Viral Contagion From Sneezing And Coughing, K. Liu, M. Allahyari, J. Salinas, ‪Nadim Zgheib, S. Balachandar Jun 2021

Investigation Of Theoretical Scaling Laws Using Large Eddy Simulations For Airborne Spreading Of Viral Contagion From Sneezing And Coughing, K. Liu, M. Allahyari, J. Salinas, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications and Presentations

Using a set of large eddy point-particle simulations, we explore the fluid dynamics of an ejected puff resulting from a cough/sneeze. The ejection contains over 61 000 potentially virus-laden droplets at an injection Reynolds number of about 46 000, comparable to an actual cough/sneeze. We observe that global puff properties, such as centroid, puff volume, momentum, and buoyancy vary little across realizations. Other properties, such as maximum extent, shape, and edge velocity of the puff, may exhibit substantial variation. In many realizations, a portion of the puff splits off and advances along a random direction, while keeping airborne droplet nuclei …


A State-Of-The-Art Review Of Laser-Assisted Bioprinting And Its Future Research Trends, Chaoran Dou, Victoria Perez, Jie Qu, Andrew Tsin, Ben Xu, Jianzhi Li Jun 2021

A State-Of-The-Art Review Of Laser-Assisted Bioprinting And Its Future Research Trends, Chaoran Dou, Victoria Perez, Jie Qu, Andrew Tsin, Ben Xu, Jianzhi Li

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Bioprinting is an additive manufacturing technology with great potential in medical applications. Among available bioprinting techniques, laser-assisted bioprinting (LAB) is a promising technique due to its high resolution, high cell viability, and the capability to deposit high-viscousity bioink. These characteristics allow the LAB technology to control cells precisely to reconstruct living organs. Recent developments of LAB technologies are reviewed in this paper, covering various designs of LAB printers, research progresses in energy-absorbing layer (EAL), the physical phenomenon that triggers the printing process in terms of bubble formation and jet development, printing process parameters, and major factors related to the post-printing …


Energy Harvesting Device For Powering Onboard Condition Monitoring Modules In Rail Service, Martin Amaro Jr., Constantine Tarawneh, Heinrich D. Foltz, Roberto A. Garcia Jun 2021

Energy Harvesting Device For Powering Onboard Condition Monitoring Modules In Rail Service, Martin Amaro Jr., Constantine Tarawneh, Heinrich D. Foltz, Roberto A. Garcia

Mechanical Engineering Faculty Publications and Presentations

Rail transportation plays an important role in today’s economy by delivering a large quantity of goods and passengers to various locations throughout North America in an economic and efficient manner. Bearing failure is one of the leading causes of derailments that result in significant capital loss and in extreme cases tragic human loss. The two widely used bearing health monitoring systems are the Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). These systems are reactive in nature and only give alerts when the bearings are nearing failure. To supplant that, a prototype wireless onboard condition monitoring system …


Peering Inside A Cough Or Sneeze To Explain Enhanced Airborne Transmission Under Dry Weather, Kai Liu, Majid Allahyari, Jorge S. Salinas, ‪Nadim Zgheib, S. Balachandar May 2021

Peering Inside A Cough Or Sneeze To Explain Enhanced Airborne Transmission Under Dry Weather, Kai Liu, Majid Allahyari, Jorge S. Salinas, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications and Presentations

High-fidelity simulations of coughs and sneezes that serve as virtual experiments are presented, and they offer an unprecedented opportunity to peer into the chaotic evolution of the resulting airborne droplet clouds. While larger droplets quickly fall-out of the cloud, smaller droplets evaporate rapidly. The non-volatiles remain airborne as droplet nuclei for a long time to be transported over long distances. The substantial variation observed between the different realizations has important social distancing implications, since probabilistic outlier-events do occur and may need to be taken into account when assessing the risk of contagion. Contrary to common expectations, we observe dry ambient …


Aloe Vera Extract-Based Composite Nanofibers For Wound Dressing Applications, Raul Barbosa, Alexa Villarreal, Cristobal Rodriguez, Heriberto De Leon, Robert Gilkerson, Karen Lozano May 2021

Aloe Vera Extract-Based Composite Nanofibers For Wound Dressing Applications, Raul Barbosa, Alexa Villarreal, Cristobal Rodriguez, Heriberto De Leon, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Natural, biocompatible, and biodegradable composite nanofibers made of Aloe vera extract, pullulan, chitosan, and citric acid were successfully produced via Forcespinning® technology. The addition of Aloe vera extract at different weight percent loadings was investigated. The morphology, thermal properties, physical properties, and water absorption of the nanofibers were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The developed nanofiber membranes exhibited good water absorption capabilities, synergistic antibacterial activity against Escherichia coli, and promoted cell attachment and growth. Its porous and high surface area structure make it a potential candidate for wound dressing …


Carbon Nanotori Structures For Thermal Transport Applications On Lubricants, Jaime Taha-Tijerina, Karla Aviña, Juan Manuel Martínez, Patsy Yessenia Arquieta-Guillén, Marlon González-Escobedo Apr 2021

Carbon Nanotori Structures For Thermal Transport Applications On Lubricants, Jaime Taha-Tijerina, Karla Aviña, Juan Manuel Martínez, Patsy Yessenia Arquieta-Guillén, Marlon González-Escobedo

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Carbon nanostructures have been recently applied to improve industrial manufacturing processes and other materials; such is the case for lubricants used in the metal-mechanic industry. Nanotori are toroidal carbon nanostructures, obtained from chemical treatment of multi-wall carbon nanotubes (MWCNTs). This material has been shown to have superb anti-wear and friction reduction performance, having the ability to homogeneously disperse within water in concentrations between 1-2 wt.%. Obtained results of these novel nanostructures under water mixtures and novel additives were a set point to our studies in different industrial lubricants. In the present work, nanotori structures have been applied in various filler …


Teaching Engineering Virtually: A Rapid Response To Address The Academic Challenges Generated By Covid-19, Eleazar Marquez, Samuel Garcia Mar 2021

Teaching Engineering Virtually: A Rapid Response To Address The Academic Challenges Generated By Covid-19, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications and Presentations

In this study, an alternative pedagogical model was established to address the academic challenges posed when undergraduate engineering students in a private university in Texas were mandated to seek off-campus housing due to the outbreak of COVI-19. As a result of the rapid transition to remote instruction, traditional and effective pedagogical methods implemented for in-person instruction had to be modified to overcome challenges such as the lack of academic resources, established campus practices that promote effective learning (e.g., study groups), and time-zone differences. Additionally, the instructional format had to be adjusted to ensure that the academic development of the students …


High Pressure Responsive Luminescence Of Flexible Eu3+ Doped Pvdf Fibrous Mats, Carlos Hernandez, Santosh K. Gupta, Jose P. Zuniga, Jorge Vidal, Rene Galvan, Hector Guzman, Lilian N. Chavez, Karen Lozano, Yuanbing Mao Mar 2021

High Pressure Responsive Luminescence Of Flexible Eu3+ Doped Pvdf Fibrous Mats, Carlos Hernandez, Santosh K. Gupta, Jose P. Zuniga, Jorge Vidal, Rene Galvan, Hector Guzman, Lilian N. Chavez, Karen Lozano, Yuanbing Mao

Mechanical Engineering Faculty Publications and Presentations

Exploring lanthanide doped materials and their high-pressure optical properties is important from the perspective of designing pressure sensors, piezoelectric materials, scintillators, and optoelectronic devices, just to mention a few. Understanding the high-pressure optical properties of polymeric fibrous mats provides significant advantages in terms of flexibility, tunability, facile processability, and malleability. In this work, we have developed flexible polyvinylidene difluoride (PVDF) fibrous mats doped with an Eu3+ source of Eu(NO3)3·5H2O (EN-PF) or Eu2(SO4)3 (ES-PF) by a Forcespinning® method. Microstructural analysis of these two systems indicates that Eu(NO3)3·5H2O and Eu2(SO4)3 are homogeneously distributed and dispersed into the PVDF matrix. Fiber formation …


Tunable Cspb(Br/Cl)3 Perovskite Nanocrystals And Further Advancement In Designing Light Emitting Fiber Membranes, Sk Shamim Hasan Abir, Santosh K. Gupta, A. Ibrahim, Bhupendra B. Srivastava, Karen Lozano Mar 2021

Tunable Cspb(Br/Cl)3 Perovskite Nanocrystals And Further Advancement In Designing Light Emitting Fiber Membranes, Sk Shamim Hasan Abir, Santosh K. Gupta, A. Ibrahim, Bhupendra B. Srivastava, Karen Lozano

Mechanical Engineering Faculty Publications and Presentations

Cesium lead halide perovskite nanocrystals (NCs) have drawn a great deal of interest in optoelectronic and photonic applications due to their intrinsic and attractive photoluminescence properties. Though, their commercially viability is of concern due to their intrinsic instability. In this study, blue and green luminous PMMA-CsPbX3(X=Cl/Br) fibers were fabricated via forcespinning technique, where the polymer matrix encapsulated the NCs. Blue CsPbX3 NCs (b- CPX NCs) were synthesized at ambient conditions while blue to green CsPbX3 NCs (g-CPX NCs) fine color tuning was obtained after heat treatment at 150°C.Field emission scanning electron microscopy (FESEM) shows fibers with diameters in the single …


Defect Detection In Freight Railcar Tapered-Roller Bearings Using Vibration Techniques, Constantine Tarawneh, Joseph Montalvo, Brent Wilson Feb 2021

Defect Detection In Freight Railcar Tapered-Roller Bearings Using Vibration Techniques, Constantine Tarawneh, Joseph Montalvo, Brent Wilson

Mechanical Engineering Faculty Publications and Presentations

Currently, there are two types of defect detection systems used to monitor the health of freight railcar bearings in service: wayside hot-box detection systems and trackside acoustic detection systems. These systems have proven to be inefficient in accurately determining bearing health, especially in the early stages of defect development. To that end, a prototype onboard bearing condition monitoring system has been developed and validated through extensive laboratory testing and a designated field test in 2015 at the Transportation Technology Center, Inc. in Pueblo, CO. The devised system can accurately and reliably characterize the health of bearings based on developed vibration …


Campus Carbon Footprint Study At A South Texas University, Monica Garcia, Christian Florez, Diego Lopez, Jongmin Kim, Maysam Pournik Feb 2021

Campus Carbon Footprint Study At A South Texas University, Monica Garcia, Christian Florez, Diego Lopez, Jongmin Kim, Maysam Pournik

Mechanical Engineering Faculty Publications and Presentations

A campus carbon footprint study was conducted at the University of Texas Rio Grande Valley, a Southern Texan university. This initiative was the school’s strategic plan to set a baseline for overall campus resource utilization status as well as to answer global requests to track and reduce campus greenhouse gas emissions and achieve greater sustainability on campus. For fiscal years of 2016 to 2018, an overall increase of campus carbon footprint was about 0.6%. The biggest increase was observed from sources owned or controlled by the school while the emissions associated with power usage decreased. The university’s carbon footprint was …


The Role Of Bed-Penetrating Kelvin–Helmholtz Vortices On Local And Instantaneous Bedload Sediment Transport, Liheng Guan, J. S. Salinas, ‪Nadim Zgheib, S. Balachandar Feb 2021

The Role Of Bed-Penetrating Kelvin–Helmholtz Vortices On Local And Instantaneous Bedload Sediment Transport, Liheng Guan, J. S. Salinas, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications and Presentations

We present results from open-channel, Euler–Lagrange (EL) simulations of turbulent flow over an erodible particle bed at a shear Reynolds number of Reτ=180 . Upon space and time averaging, our simulations correctly reproduce the Wong & Parker (ASCE J. Hydraul. Engng, vol. 132, issue 11, 2006, pp. 1159–1168) bedload transport relation (WP). However, local and instantaneous sediment flux shows orders of magnitude scatter around the WP prediction. Visualization of the vortical structures using swirling strength shows the existence of bed-penetrating Kelvin–Helmholtz (KH) vortex packets, which coupled with particle inertia are primarily responsible for the large scatter. The results also show …