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- Mechanical Engineering Faculty Publications and Presentations (24)
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Articles 1 - 30 of 40
Full-Text Articles in Engineering
Liver Cancer: Current And Future Trends Using Biomaterials, Sue Anne Chew, Stefania Moscato, Sachin George, Bahareh Azimi, Serena Danti
Liver Cancer: Current And Future Trends Using Biomaterials, Sue Anne Chew, Stefania Moscato, Sachin George, Bahareh Azimi, Serena Danti
Health & Biomedical Sciences Faculty Publications and Presentations
Hepatocellular carcinoma (HCC) is the fifth most common type of cancer diagnosed and the second leading cause of death worldwide. Despite advancement in current treatments for HCC, the prognosis for this cancer is still unfavorable. This comprehensive review article focuses on all the current technology that applies biomaterials to treat and study liver cancer, thus showing the versatility of biomaterials to be used as smart tools in this complex pathologic scenario. Specifically, after introducing the liver anatomy and pathology by focusing on the available treatments for HCC, this review summarizes the current biomaterial-based approaches for systemic delivery and implantable tools …
Experimental Study Of Condensation In A Thermoacoustic Cooler With Various 3d Printed Regenerators Using Water Vapor As The Working Fluid, Aibek Bekkulov, Andrew Luthen, Ben Xu
Experimental Study Of Condensation In A Thermoacoustic Cooler With Various 3d Printed Regenerators Using Water Vapor As The Working Fluid, Aibek Bekkulov, Andrew Luthen, Ben Xu
Mechanical Engineering Faculty Publications and Presentations
Thermoacoustics (TA) deals with the conversion of heat into sound and vice versa. The device that transfers energy from a low temperature reservoir to a high temperature one by utilizing acoustic work is called TA cooler (TAC). The main components of a typical TAC are a resonator, a porous regenerator (e.g. stack of parallel plates) and two heat exchangers. The thermoacoustic phenomenon takes place in the regenerator where a nonzero temperature gradient is imposed, and interacts with the sound wave. The low temperature at the cold end of TAC can be used to condense water from the humid air and …
Numerical Simulations Of The Hall–Petch Relationship In Aluminium Using Gradient-Enhanced Plasticity Model, Yooseob Song, Jaeheum Yeon, Byoungjoon Na
Numerical Simulations Of The Hall–Petch Relationship In Aluminium Using Gradient-Enhanced Plasticity Model, Yooseob Song, Jaeheum Yeon, Byoungjoon Na
Civil Engineering Faculty Publications and Presentations
+e Hall-Petch relation in aluminium is discussed based on the strain gradient plasticity framework. +e thermodynamically consistent gradient-enhanced flow rules for bulk and grain boundaries are developed using the concepts of thermal activation energy and dislocation interaction mechanisms. It is assumed that the thermodynamic microstresses for bulk and grain boundaries have dissipative and energetic contributions, and in turn, both dissipative and energetic material length scale parameters are existent. Accordingly, two-dimensional finite element simulations are performed to analyse characteristics of the Hall–Petch strengthening and the Hall–Petch constants. +e proposed flow rules for the grain boundary are validated using the existing experimental …
Synergistic Effect Of Nanocoatings For Corrosion And Wear Protection Of Steel Surfaces, Jaime Taha-Tijerina, Laura Peña Parás, Antonio Sánchez Fernández, Demófilo Maldonado Cortés, Pablo Sarmiento Barbosa, Jesús Rolando Adán López
Synergistic Effect Of Nanocoatings For Corrosion And Wear Protection Of Steel Surfaces, Jaime Taha-Tijerina, Laura Peña Parás, Antonio Sánchez Fernández, Demófilo Maldonado Cortés, Pablo Sarmiento Barbosa, Jesús Rolando Adán López
Informatics and Engineering Systems Faculty Publications and Presentations
The purpose of this paper is to evaluate the corrosion and wear protection of a steel substrate by epoxy vinyl ester nanocomposite coatings with Zn and TiO2 nanoparticle fillers. Steel substrates were coated with epoxy vinyl ester nanocomposites, varying Zn and TiO2 nanofiller concentrations and combinations of both nanoparticles. Corrosion resistance was evaluated by salt spray fog test during 480 h, according to ASTM B-117. The degree of damage was obtained quantitatively by measuring the enhancement in corroded area compared to the scribe mark. Tribological evaluation was performed with a ball-on-disk tribotester, according to ASTM G-99. Results showed that the …
Investigation Into The Thermodynamics And Kinetics Of The Binding Of Cu2+ And Pb2+ To Tis2 Nanoparticles Synthesized Using A Solvothermal Process, Jesus Cantu, John Valle, Kenneth Flores, Diego Gonzalez, Carolina Valdes, Jorge Lopez, Victoria Padilla, Mataz Alcoutlabi, Jason Parsons
Investigation Into The Thermodynamics And Kinetics Of The Binding Of Cu2+ And Pb2+ To Tis2 Nanoparticles Synthesized Using A Solvothermal Process, Jesus Cantu, John Valle, Kenneth Flores, Diego Gonzalez, Carolina Valdes, Jorge Lopez, Victoria Padilla, Mataz Alcoutlabi, Jason Parsons
Mechanical Engineering Faculty Publications and Presentations
In the present study, titanium (IV) sulfide (TiS2) was synthesized and investigated for the removal of Cu2+ and Pb2+ ions from aqueous solutions. TiS2 nanoparticles synthesized through a solvothermal synthesis were characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM). The average particle size for the TiS2 material was determined to be 8.03 ± 0.98 nm from the diffraction pattern. Studies were performed to examine the effects of pH, temperature, time, and interfering ions on the binding of Cu2+ and Pb2+ to the TiS2. As well isotherm studies were performed to determine the binding capacity of TiS2 for both …
Energy And Exergy Analysis Of A Novel Multiple-Effect Vapor Chamber Distillation System For High-Salinity Wastewater Treatment, Hamidreza Shabgard, Ramkumar Parthasarathy, Ben Xu
Energy And Exergy Analysis Of A Novel Multiple-Effect Vapor Chamber Distillation System For High-Salinity Wastewater Treatment, Hamidreza Shabgard, Ramkumar Parthasarathy, Ben Xu
Mechanical Engineering Faculty Publications and Presentations
A novel modular thermally-driven multiple-effect vapor chamber distillation (MVCD) system is presented for compact and portable desalination applications. The MVCD system consists of several vapor chambers connected in series with the condenser section of the upstream vapor chambers serving as the evaporator section of the following effect. A heat transfer model accounting for the major thermal resistances was developed to predict the heat transfer and distilled water production rates. A mass transfer analysis was performed to evaluate the effect of the accumulation of the non-condensable gasses within the chambers. An exergy analysis was also conducted to quantify the efficiency of …
Novel Silica Filled Deep Eutectic Solvent Based Nanofluids For Energy Transportation, Changhui Liu, Hui Fang, Xinjian Liu, Ben Xu, Zhonghao Rao
Novel Silica Filled Deep Eutectic Solvent Based Nanofluids For Energy Transportation, Changhui Liu, Hui Fang, Xinjian Liu, Ben Xu, Zhonghao Rao
Chemistry Faculty Publications and Presentations
Liquid range of nanofluids is a crucial parameter as it intensively determines their application temperature scope. Meanwhile, improved thermal conductivity and stability are of great significances and comprise the main fundamental research topics of nanofluids. In this work, 2- butoxy-3,4-dihydropyran (DP), produced from a convenient one-pot three-component reaction in water, was employed as dual lipophilic brusher and metal nanoparticle anchor. It was found that DP was able to enhance the dispersing ability and thermal conductivity of SiO2 nanoparticle filled deep eutectic solvent (DES) based nanofluids simultaneously. The key to the success of this protocol mainly relies on the electrophilic property …
Novel Silica Filled Deep Eutectic Solvent Based Nanofluids For Energy Transportation, Changhui Liu, Hui Fang, Xinjian Liu, Ben Xu, Zhonghao Rao
Novel Silica Filled Deep Eutectic Solvent Based Nanofluids For Energy Transportation, Changhui Liu, Hui Fang, Xinjian Liu, Ben Xu, Zhonghao Rao
Mechanical Engineering Faculty Publications and Presentations
Liquid range of nanofluids is a crucial parameter as it intensively determines their application temperature scope. Meanwhile, improved thermal conductivity and stability are of great significances and comprise the main fundamental research topics of nanofluids. In this work, 2-butoxy-3,4-dihydropyran (DP), produced from a convenient one-pot three-component reaction in water, was employed as dual lipophilic brusher and metal nanoparticle anchor. It was found that DP was able to enhance the dispersing ability and thermal conductivity of SiO2 nanoparticle filled deep eutectic solvent (DES) based nanofluids simultaneously. The key to the success of this protocol mainly relies on the electrophilic property and …
Sub-Optimal Tracking In Switched Systems With Controlled Subsystems And Fixed-Mode Sequence Using Approximate Dynamic Programming, Tohid Sardarmehni, Xingyong Song
Sub-Optimal Tracking In Switched Systems With Controlled Subsystems And Fixed-Mode Sequence Using Approximate Dynamic Programming, Tohid Sardarmehni, Xingyong Song
Mechanical Engineering Faculty Publications and Presentations
Optimal tracking in switched systems with controlled subsystem and Discrete-time (DT) dynamics is investigated. A feedback control policy is generated such that a) the system tracks the desired reference signal, and b) the optimal switching time instants are sought. For finding the optimal solution, approximate dynamic programming is used. Simulation results are provided to illustrate the effectiveness of the solution.
Pressure Effect On An Ocean-Based Humidification-Dehumidification Desalination Process, Yingchen Yang
Pressure Effect On An Ocean-Based Humidification-Dehumidification Desalination Process, Yingchen Yang
Mechanical Engineering Faculty Publications and Presentations
A new humidification-dehumidification (HDH) desalination process is proposed and analyzed. Being ocean based, the process does not produce any brine. It is largely powered jointly by solar energy, wind energy, and various types of ocean energies in a nearly natural way. A vacuum pump is employed to drive the air circulation throughout the HDH process. It is the only unit that consumes electricity. The HDH process is analyzed under various conditions, including using a low pressure (as low as to 0.2 atm) for humidification and the ambient pressure for dehumidification, running the entire HDH process around a low pressure (as …
Can Routers Provide Sufficient Protection Against Cyber Security Attacks?, David Leal, Sanjeev Kumar
Can Routers Provide Sufficient Protection Against Cyber Security Attacks?, David Leal, Sanjeev Kumar
Electrical and Computer Engineering Faculty Publications and Presentations
Nowadays many devices that make up a computer network are being equipped with security hardware and software features to prevent cyber security attacks. The idea is to distribute security features to intermediate systems in the network to mitigate the overall adverse effect of cyber attacks. In this paper, we will be focusing on the Juniper J4350 router with the Junos Software Enhanced, and it has security-attack protections in the router. We are going to evaluate how the Juniper router with built-in security protections affected the overall server performance under a cyber security attack.
A Physically Based Constitutive Model For Dynamic Strain Aging In Inconel 718 Alloy At A Wide Range Of Temperatures And Strain Rates, George Z. Voyiadjis, Yooseob Song
A Physically Based Constitutive Model For Dynamic Strain Aging In Inconel 718 Alloy At A Wide Range Of Temperatures And Strain Rates, George Z. Voyiadjis, Yooseob Song
Civil Engineering Faculty Publications and Presentations
Dynamic strain aging has a huge effect on the microstructural mechanical behavior of Inconel 718 high-performance alloy when activated. In a number of experimental researches, significant additional hardening due to the dynamic strain aging phenomenon was reported. A constitutive model without considering dynamic strain aging is insufficient to accurately predict the material behavior. In this paper, a new constitutive model for Inconel 718 high-performance alloy is proposed to capture the additional hardening, which is caused by dynamic strain aging, by means of the Weibull distribution probability density function. The derivation of the proposed constitutive relation for the dynamic strain aging-induced …
Centrifugally Spun Α-Fe2o3/Tio2/Carbon Composite Fibers As Anode Materials For Lithium-Ion Batteries, Luis Zuniga, Gabriel Gonzalez, Roberto Orrostieta Chavez, Jason C. Myers, Timothy P. Lodge, Mataz Alcoutlabi
Centrifugally Spun Α-Fe2o3/Tio2/Carbon Composite Fibers As Anode Materials For Lithium-Ion Batteries, Luis Zuniga, Gabriel Gonzalez, Roberto Orrostieta Chavez, Jason C. Myers, Timothy P. Lodge, Mataz Alcoutlabi
Mechanical Engineering Faculty Publications and Presentations
We report results on the electrochemical performance of flexible and binder-free α-Fe2O3/TiO2/carbon composite fiber anodes for lithium-ion batteries (LIBs). The composite fibers were produced via centrifugal spinning and subsequent thermal processing. The fibers were prepared from a precursor solution containing PVP/iron (III) acetylacetonate/titanium (IV) butoxide/ethanol/acetic acid followed by oxidation at 200 °C in air and then carbonization at 550 °C under flowing argon. The morphology and structure of the composite fibers were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), …
A Comparison Of Three Types Of Permeable Pavements For Urban Runoff Mitigation In The Semi-Arid South Texas, U.S.A, Taufiqul Alam, Ahmed Mahmoud, Kim D. Jones, Juan Cesar Bezares-Cruz, Javier Guerrero
A Comparison Of Three Types Of Permeable Pavements For Urban Runoff Mitigation In The Semi-Arid South Texas, U.S.A, Taufiqul Alam, Ahmed Mahmoud, Kim D. Jones, Juan Cesar Bezares-Cruz, Javier Guerrero
Civil Engineering Faculty Publications and Presentations
This study examines the hydrologic and environmental performance of three types of permeable pavement designs: Porous Concrete Pavement (PCP), Permeable Interlocking Concrete (PICP), and Interlocking Block Pavement with Gravel (IBPG) in the semi-arid South Texas. Outflow rate, storage, Normalized Volume Reduction (NVR), Normalized Load Reductions (NLR) of Total Suspended Solids (TSS), and Biochemical Oxygen Demand (BOD5) were compared to results obtained from adjacent traditional pavements at different regional parking lots. A notable percentage of peak flow attenuation of approximately 31–100% was observed when permeable pavements were constructed and implemented. IBPG was capable to hold runoff from rainfall depths …
Winslamm Simulation Of Hydrologic Performance Of Permeable Pavements—A Case Study In The Semi-Arid Lower Rio Grande Valley Of South Texas, United States, Taufiqul Alam, Ahmed Mahmoud, Kim D. Jones, Juan Cesar Bezares-Cruz, Javier Guerrero
Winslamm Simulation Of Hydrologic Performance Of Permeable Pavements—A Case Study In The Semi-Arid Lower Rio Grande Valley Of South Texas, United States, Taufiqul Alam, Ahmed Mahmoud, Kim D. Jones, Juan Cesar Bezares-Cruz, Javier Guerrero
Civil Engineering Faculty Publications and Presentations
his study used the Source Loading and Management Model for Windows (WinSLAMM) to develop a set of calibrated hydrologic models for three types of regional permeable pavements—porous concrete pavement (PCP), permeable interlocking concrete pavement (PICP), and interlocking block pavement with gravel (IBPG). The objective was to assess the hydrologic performance of permeable pavements, including the runoff depth, peak discharge, percentage increment in runoff reduction of pavements as a function of rainfall depth, development area, and base aggregate porosity, respectively. The permeable pavements were monitored over a wide range of rainfall events in the semi-arid Lower Rio Grande Valley of South …
Evaluating The Rheological And Tribological Behaviors Of Coconut Oil Modified With Nanoparticles As Lubricant Additives, Vicente Cortes, Javier A. Ortega
Evaluating The Rheological And Tribological Behaviors Of Coconut Oil Modified With Nanoparticles As Lubricant Additives, Vicente Cortes, Javier A. Ortega
Mechanical Engineering Faculty Publications and Presentations
In metal-forming processes, the use of lubricants for providing desirable tribological conditions at the tool–workpiece interface is critical to increase the material formability and prolonging tool life. Nowadays, the depletion of crude oil reserves in the world and the global concern in protecting the environment from contamination have renewed interest in developing environmentally-friendly lubricants derived from alternative sources such as vegetable oils. In the present study, the rheological and tribological behavior of coconut oil modified with nanoparticle additives was experimentally evaluated. Two different nanoparticle additives were investigated: Silicon dioxide (SiO2) and copper oxide (CuO). For the two conditions, …
Tribological And Thermal Transport Performance Of Sio2-Based Natural Lubricants, Jaime Taha-Tijerina, Karla Aviña, Jose Manual Diabb
Tribological And Thermal Transport Performance Of Sio2-Based Natural Lubricants, Jaime Taha-Tijerina, Karla Aviña, Jose Manual Diabb
Informatics and Engineering Systems Faculty Publications and Presentations
Fluids and lubricants are critical for the mechanical manufacturing processing of metals, due to a high amount of friction generated, also reflected as heat, could wear and damage tooling and machine components. The proper application of lubricants increases machinery lifetime, decreases long-term costs, and energy and time consumption due to the maintenance or components exchange/repairs. Besides being non-renewable, mineral oils bring consequences to the environment due to their low biodegradability and could affect the user with respiratory and skin diseases. Recently, due to an increase in environmental awareness, the search of biocompatible and efficient lubricants has become a technology goal. …
Design And Validation Of A Modular Instrument To Measure Torque And Energy Consumption In Industrial Operations, Mary De La Cruz, Ramiro Gonzalez, Jesus A. Gomez, Atilano Mendoza, Javier A. Ortega
Design And Validation Of A Modular Instrument To Measure Torque And Energy Consumption In Industrial Operations, Mary De La Cruz, Ramiro Gonzalez, Jesus A. Gomez, Atilano Mendoza, Javier A. Ortega
Mechanical Engineering Faculty Publications and Presentations
A modular torque measuring instrument capable of performing tapping torque tests (TTT) according to the ASTM D-5619 standard was designed, developed, and validated. With this new instrument, the performance of different lubricants can be evaluated in terms of frictional torque and energy consumption during tapping processes. This instrument can adapt onto any conventional milling machine or CNC machine and operate under various machining operations such as tapping, drilling, and other processes. To validate the design and performance of this new device, three commercially available lubricants were evaluated. From the three tested conditions, the results showed good repeatability, with consistent results …
Raman Spectroscopy And Molecular Bases Of Elasticity: Sebs-Graphite Composites, Dorina M. Chipara, Denis M. Panaitescu, Karen Lozano, Raluca Augusta Gabor, Cristian Andi Nicolae, Mircea Chipara
Raman Spectroscopy And Molecular Bases Of Elasticity: Sebs-Graphite Composites, Dorina M. Chipara, Denis M. Panaitescu, Karen Lozano, Raluca Augusta Gabor, Cristian Andi Nicolae, Mircea Chipara
Mechanical Engineering Faculty Publications and Presentations
For polymer-based (nano)composites, the strain/stress induced by reinforcing agents within the polymer may be identified and quantified at molecular level by Raman spectroscopy. The manuscript focuses on correlations between mechanical properties of composites and their Raman spectra, with emphasis on the displacements of the position(s) of Raman lines due to local strains/stress. Investigations on polystyrene-(ethylene-co-butylene)-styrene block copolymers filled with various amounts of graphite are reported. The modifications of Raman's parameters (line intensity, position, and width) upon the loading with graphite are analyzed. Raman revealed a strong dampening of molecular vibrations within the polymer, upon the loading with graphite, …
On The Role Of Sidewalls In The Transition From Straight To Sinuous Bedforms, Nadim Zgheib, S. Balachandar
On The Role Of Sidewalls In The Transition From Straight To Sinuous Bedforms, Nadim Zgheib, S. Balachandar
Mechanical Engineering Faculty Publications and Presentations
We present results from direct numerical simulation on the transition from straight-crested to sinuous-crested bedforms. The numerical setup is representative of turbulent open channel flow over an erodible sediment bed at a shear Reynolds number of Reτ = 180. The immersed boundary method accounts for the presence of the bed. The simulations are two-way coupled such that the turbulent flow can erode and modify the bed, and in turn, the bed modifies the overlying flow. Coupling from the flow to the bed occurs through the Exner equation, while back coupling from the bed to the flow is achieved by …
Prognostics Models For Railroad Tapered Roller Bearings With Spall Defects On Inner Or Outer Rings, Constantine Tarawneh, Jennifer Lima, Nancy De Los Santos, Robert Jones
Prognostics Models For Railroad Tapered Roller Bearings With Spall Defects On Inner Or Outer Rings, Constantine Tarawneh, Jennifer Lima, Nancy De Los Santos, Robert Jones
Mechanical Engineering Faculty Publications and Presentations
Rolling contact fatigue (RCF) is one of the major causes of failure in railroad bearings used in freight service. Subsurface inclusions resulting from impurities in the steel used to fabricate the bearings initiate subsurface fatigue cracks, which propagate upwards and cause spalling of the rolling surfaces. These spalls start small and propagate as continued operation induces additional crack formation and spalling. Studies have shown that the bearing temperature is not a good indicator of spall initiation. In many instances, the temperature of the bearing increases markedly only when the spall has spread across major portions of the raceway. In contrast, …
Effects Of Epoxy Adhesive Layer Thickness On Bond Strength Of Joints In Concrete Structures, Jaeheum Yeon, Yooseob Song, Kwan Kyu Kim, Julian Kang
Effects Of Epoxy Adhesive Layer Thickness On Bond Strength Of Joints In Concrete Structures, Jaeheum Yeon, Yooseob Song, Kwan Kyu Kim, Julian Kang
Civil Engineering Faculty Publications and Presentations
In the construction field, adhesives are frequently used to improve adhesion between two objects. Epoxy adhesives are applied as long-term solutions, improving the bond between repair materials and existing concrete structures. Experimental investigations of the relationship between the thickness of an adhesive layer and its shear strength have been conducted by a number of industries outside of the construction sector. However, that research used metal plates as adherends when determining the shear strengths of epoxy adhesives. Therefore, this study examines epoxy adhesives’ shear strength development when applied to concrete adherends. The test results show that the thickness of the bond …
Multidirectional Pin-On-Disk Testing Device To Evaluate The Cross-Shear Effect On The Wear Of Biocompatible Materials, Vicente Cortes, Carlos A. Rodriguez Betancourth, Javier A. Ortega, Hasina Huq
Multidirectional Pin-On-Disk Testing Device To Evaluate The Cross-Shear Effect On The Wear Of Biocompatible Materials, Vicente Cortes, Carlos A. Rodriguez Betancourth, Javier A. Ortega, Hasina Huq
Mechanical Engineering Faculty Publications and Presentations
One of the main causes of hip prostheses failure is the premature wear of their components. Multi-directional motion or “cross-shear” motion has been identified as one of the most significant factors affecting the wear rate of UHMWPE in total hip joint replacement prostheses. To better evaluate the effect of this cross-shear motion on the tribological behavior of different biomaterials, a new wear testing device has been designed and developed. This new instrument is capable to reproduce the “cross-shear” effect with bidirectional motion on bearing materials and to determine coefficient of friction (COF) between surfaces during testing. To validate the functionality …
Prototyping A Conductive Polymer Steering Pad For Rail Freight Service, Anthony A. Villarreal, Constantine Tarawneh, Miguel Ontiveros, James Aranda, Robert Jones
Prototyping A Conductive Polymer Steering Pad For Rail Freight Service, Anthony A. Villarreal, Constantine Tarawneh, Miguel Ontiveros, James Aranda, Robert Jones
Mechanical Engineering Faculty Publications and Presentations
The AdapterPlus™ steering pad is a polymer component on a railcar that helps to reduce stresses on the axle as a railcar rounds a curve. One railway application requires a minimum of 240 mA to be passed through the steering pad to the rail, which activates air valves that control automated cargo gates. Currently, two copper studs are inserted into the pad to provide a conductive path. However, after continuous cyclic loading caused by normal service operation, the copper studs deform, wear, and eventually lose contact between the two surfaces rendering the pad nonconductive. One proposed solution to this problem …
Estimating The Outer Ring Defect Size And Remaining Service Life Of Freight Railcar Bearings Using Vibration Signatures, Joseph Montalvo, Constantine Tarawneh, Jennifer Lima, Jonas Cuanang, Nancy De Los Santos
Estimating The Outer Ring Defect Size And Remaining Service Life Of Freight Railcar Bearings Using Vibration Signatures, Joseph Montalvo, Constantine Tarawneh, Jennifer Lima, Jonas Cuanang, Nancy De Los Santos
Mechanical Engineering Faculty Publications and Presentations
The railroad industry currently utilizes two wayside detection systems to monitor the health of freight railcar bearings in service: The Trackside Acoustic Detection System (TADS™) and the wayside Hot-Box Detector (HBD). TADS™ uses wayside microphones to detect and alert the conductor of high-risk defects. Many defective bearings may never be detected by TADS™ since a high-risk defect is a spall which spans more than 90% of a bearing’s raceway, and there are less than 20 systems in operation throughout the United States and Canada. Much like the TADS™, the HBD is a device that sits on the side of the …
Implementation Of Visual Supplements To Strengthen Pedagogical Practices And Enhance The Physical Understanding Of Fundamental Concepts In Engineering Mechanics, Eleazar Marquez, Samuel Garcia, Samuel Molina
Implementation Of Visual Supplements To Strengthen Pedagogical Practices And Enhance The Physical Understanding Of Fundamental Concepts In Engineering Mechanics, Eleazar Marquez, Samuel Garcia, Samuel Molina
Mechanical Engineering Faculty Publications and Presentations
Mechanical Engineering is a discipline highly dependent on designing and implementing mechanical, thermal, or energy systems for the improvement of the human environment. Thus being a proficient Engineer involves having a strong mathematical background and a thorough physical understanding on how systems operate in order to apply analytical or numerical schemes during a design process. However, most of the students’ academic development is centered on deriving tedious equations and solving textbook problems, which are difficult to visualize and physically understand, and cloud their intuitive nature to comprehend a problem on its entirety. These conventional approaches and methods of disseminating content …
Zinc Ferrite Based Gas Sensors: A Review, Kaidi Wu, Jianzhi Li, Chao Zhang
Zinc Ferrite Based Gas Sensors: A Review, Kaidi Wu, Jianzhi Li, Chao Zhang
Manufacturing & Industrial Engineering Faculty Publications and Presentations
Flammable, explosive and toxic gases, such as hydrogen, hydrogen sulfide and volatile organic compounds vapor, are major threats to the ecological environment safety and human health. Among the available technologies, gas sensing is a vital component, and has been widely studied in literature for early detection and warning. As a metal oxide semiconductor, zinc ferrite (ZnFe2O4) represents a kind of promising gas sensing material with a spinel structure, which also shows a fine gas sensing performance to reducing gases. Due to its great potentials and widespread applications, this article is intended to provide a review on the latest development in …
Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota
Incorporating Antecedent Soil Moisture Into Streamflow Forecasting, Abdoul Oubeidillah, Glenn Tootle, Thomas Piechota
Civil Engineering Faculty Publications and Presentations
This study incorporates antecedent (preceding) soil moisture into forecasting streamflow volumes within the North Platte River Basin, Colorado/Wyoming (USA). The incorporation of antecedent soil moisture accounts for infiltration and can improve streamflow predictions. Current Natural Resource Conservation Service (NRCS) forecasting methods are replicated, and a comparison is drawn between current NRCS forecasts and proposed forecasting methods using antecedent soil moisture. Current predictors used by the NRCS in regression-based streamflow forecasting include precipitation, streamflow persistence (previous season streamflow volume) and snow water equivalent (SWE) from SNOTEL (snow telemetry) sites. Proposed methods utilize antecedent soil moisture as a predictor variable in addition …
Creating A Learning Environment That Engages Engineering Students In The Classroom Via Communication Strategies, Eleazar Marquez, Samuel Garcia
Creating A Learning Environment That Engages Engineering Students In The Classroom Via Communication Strategies, Eleazar Marquez, Samuel Garcia
Mechanical Engineering Faculty Publications and Presentations
In this research effort, the authors claim that possessing technical knowledge is not a sufficient asset to establish a learning environment that renders engagement with engineering students during lecture sessions, but rather the integration of various communication strategies that support students’ academic development. Research has noted that classroom context and conditions impact the degree of student learning and engagement and are further enhanced when students feel comfortable communicating with the instructor and with their peers. If such acquaintance is nonexistent, student participation may be stifled and limited despite the technical concerns arising during lecture sessions. Thus, it is imperative for …
Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah
Tree-Ring Reconstructions Of Streamflow For The Tennessee Valley, Sallyrose Anderson, Ross Ogle, Glenn Tootle, Abdoul Oubeidillah
Civil Engineering Faculty Publications and Presentations
This study reports the preliminary results from a statistical screening of tree-ring width records from the International Tree-Ring Data Bank (ITRDB), to evaluate the strength of the hydrological signal, in dendrochronological records from the Tennessee Valley. We used United States Geological Survey (USGS) streamflow data from 11 gages, within the Tennessee Valley, and regional tree-ring chronologies, to analyze the dendroclimatic potential of the region, and create seasonal flow reconstructions. Prescreening methods included correlation, date, and temporal stability analysis of predictors to ensure practical and reliable reconstructions. Seasonal correlation analysis revealed that large numbers of regional tree-ring chronologies were significantly correlated …