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Articles 571 - 600 of 657
Full-Text Articles in Mechanical Engineering
Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo
Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo
Theses and Dissertations - UTB/UTPA
This thesis work deals with electrostatically actuated Carbon Nanotubes (CNTs) cantilevers. Four forces are acting on the CNTs cantilever, namely damping, elastic, electrostatic and van der Waals forces. The van der Waals force is significant for values of 50 nm or lower of the gap between the CNTs and the ground substrate. As both electrostatic and van der Waals forces are nonlinear, and the CNTs electrostatic actuation is given by alternating current (AC) voltage, the CNTs undergo nonlinear parametric dynamics. The Method of Multiple Scales (MMS) and Reduced Order Model (ROM) are employed to investigate the system under soft excitation …
Design And Optimization Of A Railroad Conductive Suspension Element Pad Composed Of Thermoplastic Polyurethane And Carbon Black, Ruben Suarez Jr.
Design And Optimization Of A Railroad Conductive Suspension Element Pad Composed Of Thermoplastic Polyurethane And Carbon Black, Ruben Suarez Jr.
Theses and Dissertations - UTB/UTPA
The AdapterPlus™ Pad, made from thermoplastic polyurethane (TPU), is used to enhance steering and prevent metal-to-metal contact between the railcar side frame and the bearing adapter. Although the AdapterPlus™ Pad acts as a pedestal liner in the suspension assembly, it must allow electric current to flow from the rail, through the bearing adapter wall to the side frame in order to activate a solenoid air valve that releases cargo gates. Currently, the pad uses copper inserts that allow current through. Because the Adapter Plus™ Pad is subject to large dynamic loads, the copper inserts permanently deform losing contact and cutting …
Development Of Hydrodynamic Channel Routing Model Of The Lower Rio Grande River To Assist In Flood And Stormwater Management, Andrew W. Leeper
Development Of Hydrodynamic Channel Routing Model Of The Lower Rio Grande River To Assist In Flood And Stormwater Management, Andrew W. Leeper
Theses and Dissertations - UTB/UTPA
Flooding and stormwater management of the Lower Rio Grande River (LRG) has become a major issue throughout the years with local entities along the river. The purpose of this study is to develop a hydrodynamic channel routing model to predict water surface elevation changes due to flooding. The study area consists of the LRG from Los Ebanos to Brownsville, Texas. This hydrodynamic model displays the hydraulics of the water flow through the LRG and determines where potential flood hazards exist. To verify the accuracy of the model a series of calculated output hydrographs were established at the Progreso Bridge and …
Calibration And Optimization Of A Load Sensor Embedded In A Railroad Bearing Adapter, Lorenzo Saenz Iv
Calibration And Optimization Of A Load Sensor Embedded In A Railroad Bearing Adapter, Lorenzo Saenz Iv
Theses and Dissertations - UTB/UTPA
Freight railcars rely heavily on weigh bridges and stations to determine cargo load. As a consequence, all load measurements are limited to certain locations and specified prices. To this end, this study presents work performed to develop one of the first economical, reliable sensors for keeping track of both dynamic and static loads on a freight railcar. Preliminary testing provided a strain-gauge based sensor that delivered load information in the laboratory environment. Federal Railroad Association (FRA) protocol testing was met and consistent results were obtained from the sensing device. The latter allowed for an optimized sensor that could potentially deliver …
Proper Orthogonal Decomposition Of High-Speed Flows, Oscar Huerta
Proper Orthogonal Decomposition Of High-Speed Flows, Oscar Huerta
Theses and Dissertations - UTB/UTPA
In an effort to understand physical characteristics of high speed flows such as an Impinging Jet (Mach 1.5) and Pulsed Jet (Mach 0.3) both propulsions systems are investigated from phased-locked Particle Image Velocimetry (PIV) data that is analyzed using Proper Orthogonal Decomposition (POD). The purpose of POD is to extract the most dominant features found in the flow. The method calculates the eigenvalues and the spatial eigenfunctions that are related to the total kinetic energy with only a few basis functions. Results for an Impinging Jet show about 70% of the energy in the first twenty modes that represent the …
Experimental Study Of Nanofiber Production Through Forcespinning, Simon Padron, Arturo Fuentes, Dumitru Caruntu, Karen Lozano
Experimental Study Of Nanofiber Production Through Forcespinning, Simon Padron, Arturo Fuentes, Dumitru Caruntu, Karen Lozano
Mechanical Engineering Faculty Publications
A newly developed method of producing nanofibers, called forcespinning, has proven to be a viable alternative to mass produce nanofibers. Unlike electrospinning, the most common method currently being employed (which draws fibers through the use of electrostatic force), forcespinning utilizes centrifugal forces which allow for a host of new materials to be processed into nanofibers (given that electric fields are not required) while also providing a significant increase in yield and ease of production. This work presents a detailed explanation of the fiber formation process. The study is conducted using high speed photography to capture the jet initiation process at …
Fabrication And Characterization Of Polylactic Acid And Polylactic Acid/Multi-Walled Carbon Nanotube Nanofibers Through Centrifugal Spinning, Richard Patlan
Fabrication And Characterization Of Polylactic Acid And Polylactic Acid/Multi-Walled Carbon Nanotube Nanofibers Through Centrifugal Spinning, Richard Patlan
Theses and Dissertations - UTB/UTPA
Biocompatible polymer nanofibers hold great potential in the biomedical engineering field. Their biodegradable nature and enhanced properties could help solve a wide array of health related problems, particularly in the areas of tissue regeneration, drug delivery, and biosensor design. The novel ForcespinningTM method allows the production of submicron fibers without many of the drawbacks found in electrospinning, while also providing a substantial increase in fiber production. The aim of the study was to utilize this method to fabricate non-woven nanofibrous mats composed of polylactic acid (PLA) and polylactic acid/multi-walled carbon nanotube composite fibers. The morphology, thermal properties, and crystalline structure …
Development Of A Vibration And Temperature Measurement Device For Railroad Bearings, Andrea P. Arguelles
Development Of A Vibration And Temperature Measurement Device For Railroad Bearings, Andrea P. Arguelles
Theses and Dissertations - UTB/UTPA
Bearing related derailments cause very high cost and inconvenience to the railroad industry. Various wayside detection systems have been implemented to assess bearing condition and prevent premature failure. However, current devices fail to determine the internal condition of bearings or provide insight regarding the danger and severity of defects and abnormalities that may be present. To this end, a device combining both temperature and vibration detection was designed to be embedded in railroad bearing adapters. In order to efficiently design a railroad bearing condition-monitoring system, two factors that must be considered are the capabilities available to operate the different sensors …
Defect Detection In Railroad Tapered-Roller Bearings Using Vibration Analysis Techniques, Iris L. Alvarado
Defect Detection In Railroad Tapered-Roller Bearings Using Vibration Analysis Techniques, Iris L. Alvarado
Theses and Dissertations - UTB/UTPA
Derailments can often lead to great damage, loss of lives, and massive costs associated with the railroad infrastructure. A significant cause of derailments is premature bearing failure, and therefore bearing condition-monitoring systems that can detect developing defects are of great importance. Based on an investigation conducted at the University of Texas-Pan American on the development of a vibration and temperature monitoring system, an algorithm is devised utilizing various vibration analysis techniques. The proposed algorithm determines whether a bearing is defective, the type of defect present, the defective component (i.e. cup, cone, or roller), and the size of the defect. Speed-dependent …
Improving The Mechanical Properties Of Polymers By Adding Self-Healing Capabilities, Alma Perez
Improving The Mechanical Properties Of Polymers By Adding Self-Healing Capabilities, Alma Perez
Theses and Dissertations - UTB/UTPA
The addition of self-healing capabilities to polymers through the dispersion of First Generation Grubbs’ Catalyst (FGGC) and poly(urea-formaldehyde) (PUF) microcapsules filled with dicyclopentadiene (DCPD) as the healing agent, has been investigated by various experimental techniques such as Optical microscopy, Scanning Electron Microscopy, Tensile tests, Raman Spectroscopy, and Themogravimmetric Analysis (TGA). Optical and Scanning Electron Microscopy revealed the morphology of the surface of the PUF microcapsules, the diameter size distribution and the thickness of the shell, and their structure when dispersed in the polymeric matrices. Photos taken after the tensile test showed broken microcapsules on both polymer matrices having released the …
Development Of Algorithms And Criteria For Continuous Condition Monitoring Of Railroad Bearings, Sean Michael Woods
Development Of Algorithms And Criteria For Continuous Condition Monitoring Of Railroad Bearings, Sean Michael Woods
Theses and Dissertations - UTB/UTPA
This thesis summarizes research conducted at the University of Texas-Pan American to investigate the implementation of condition monitoring algorithms for use with railway roller bearings equipped with wireless temperature sensor nodes. Current temperature based condition monitoring techniques utilize wayside detection equipment intermittently located along the track to garner sporadic bearing cup temperatures. Such devices are not capable of detecting brief transient temperature trending events. The developed algorithms were tested using a fleet of ten railway freight cars instrumented with wireless sensor nodes and operated by an Australian freight transportation company. Eighteen months of continuous monitoring combined with the inspection of …
Control Charts For First Order Autoregressive Analysis With An Exogenous Variable, Becky M. Vela
Control Charts For First Order Autoregressive Analysis With An Exogenous Variable, Becky M. Vela
Theses and Dissertations - UTB/UTPA
There are many instances in industry, where the necessity of prediction models is extremely important. However, the difficulty of forecasting increases with the number of variables involved, and determining independent variables from dependent variables. Autocorrelation is one of the most common causes for many control charts and other quality measurement tools to falsely signal an error in the process. Time series models, such as autoregressive models, accommodate autocorrelated data to a certain extent. However, using a model that only analyzes historical data alone does not possess the accuracy necessary to be able to forecast data precisely. An addition of an …
Droplet Spray Behavior Of An Atomization-Based Cutting Fluid (Acf) System For Machining Of Titanium Alloys, Chandra Nath, Shiv G. Kapoor, Anil K. Srivastava, Jon Iverson
Droplet Spray Behavior Of An Atomization-Based Cutting Fluid (Acf) System For Machining Of Titanium Alloys, Chandra Nath, Shiv G. Kapoor, Anil K. Srivastava, Jon Iverson
Manufacturing & Industrial Engineering Faculty Publications
The aim of this research is to study droplet spray characteristics of an atomization-based cutting fluid (ACF) spray system including droplet entrainment angle and flow development regions with respect to three ACF spray parameters, viz., droplet and gas velocities, and spray distance. ACF spray experiments are performed by varying droplet and gas velocities. The flow development behavior is studied by modeling the droplets entrainment mechanism, and the density and distribution of the droplets across the jet flare. Machining experiments are also performed in order to understand the effect of the droplet spray behavior on the machining performances, viz., tool life/wear, …
Adding Autonomic Healing Capabilities To Polyethylene Oxide, Dorina M. Chipara, Maritza Flores, Alma Perez, Nancy Puente, Karen Lozano, Mircea Chipara
Adding Autonomic Healing Capabilities To Polyethylene Oxide, Dorina M. Chipara, Maritza Flores, Alma Perez, Nancy Puente, Karen Lozano, Mircea Chipara
Mechanical Engineering Faculty Publications
The addition of autonomic healing (frequently defined as self-healing) capabilities to a water-soluble polymer (polyethylene oxide, PEO) is for the first time reported. The self-healing system consists of urea-formaldehyde microcapsules filled with dicyclopentadiene and first-generation Grubbs catalyst, dispersed within polyethylene oxide. Raman spectroscopy, optical microscopy, electron microscopy, and thermogravimetric analysis were used to characterize this autonomic healing system. Self-healing capabilities were confirmed by mechanical testing (load–displacement, engineering stress–engineering strain, and true stress–true strain dependences) recorded at very slow elongation rates (0.01 mm/s). The testing fate was chosen to allow for the complete consumption of the monomer before fracture (the polymerization …
Load Sensor In An Elastomer Suspension Element, Jazmin Ley
Load Sensor In An Elastomer Suspension Element, Jazmin Ley
Theses and Dissertations - UTB/UTPA
Knowledge of the loading applied to railcar suspension elements is necessary for improved rail safety, efficiency, and for monitoring bearing health. An economical, reliable system for keeping track of both dynamic and static loads on a rail car bearing offers potential for many improvements in rail service. The difficulties of implementing such a system are considerable because the sensor must be in the bearing load path and is thus subject to all the stressors of that environment including high impact, high load, high temperature, and corrosion. This thesis describes an attempt to incorporate a load measurement system in a polyurethane …
2d Modeling Of Forcespinning™ Nanofiber Formation With Experimental Study And Validation, Simon Padron
2d Modeling Of Forcespinning™ Nanofiber Formation With Experimental Study And Validation, Simon Padron
Theses and Dissertations - UTB/UTPA
A newly developed method of producing nanofibers, called Forcespinning™, has proven to be a viable alternative to mass produce nanofibers. Forcespinning™ utilizes centrifugal forces which allow for a host of new materials to be processed into nanofibers while also providing a significant increase in yield and ease of production. To improve and enhance the Forcespinning™ production method, a 2D computational Forcespinning™ fluid dynamics model is developed. Three computer models, namely time-independent and time-dependent inviscid models and a viscous model are obtained and the influences of various parameters on Forcespinning™ fiber formation are obtained. This work also presents a detailed explanation …
Electromagnetic Interference Shielding Effectiveness Of Metallic Thin Films Deposited On High Density Polyethylene And Styrene Butadiene Copolymer Reinforced With Carbon Nanofibers, Horus Garcia
Theses and Dissertations - UTB/UTPA
Aluminum, Copper and Silver were deposited by thermal evaporation onto Vapor Grown Carbon Nanofiber (VGCNF) reinforced High Density Polyethylene (HDPE) and Styrene Butadiene Copolymer (SBC) composites. Electromagnetic Interference Shielding Effectiveness (EMI SE) was conducted on the structures to analyze the synergistic effect. Characterization was performed by Scanning Electron Microscopy, X-ray Diffraction, and Atomic Force Microscopy. Adhesion test and surface influence on SE were also performed. It was observed that a single layer metallic thin film on carbon nanofiber (CNF) polymer composite experienced a summation of shielding performance. The EMI SE increased with CNF content increase of 10, 15, and 20 …
Remanufacturing Cleaning Process Evaluation, Comparison And Planning, Ozan Yagar
Remanufacturing Cleaning Process Evaluation, Comparison And Planning, Ozan Yagar
Theses and Dissertations - UTB/UTPA
This thesis aims to combine previous research on remanufacturing cleaning processes and applications into a single decision-making tool, in the form of software, which a remanufacturer can use to find a cleaning system that matches their specific demands. This thesis will provide an in-depth review of each cleaning process, the chemicals used in those processes, and the contamination types for which they were developed. This research also provides evaluation and comparison that assists remanufacturers in designing their cleaning systems. Finally, there will be a description and demonstration of the software. The ultimate goal is to find correct cleaning process to …
A Case Study For Financial Feasibility Of Automated Costing Support In A Small Machine Shop, Benito A. Gonzalez
A Case Study For Financial Feasibility Of Automated Costing Support In A Small Machine Shop, Benito A. Gonzalez
Theses and Dissertations - UTB/UTPA
A knowledge-based cost estimating expert system is chosen by a Mexican machine shop. Differences between the traditional experience-based system employed and the automated system are studied. Data is gathered to analyze time effectiveness, accuracy and payback of the software. Data from seventy part models is recorded to study the time experiment, and data from fifty part models is used to study the accuracy and consistency. Data is analyzed by calculating mean, standard deviation, and test of hypothesis. The results indicate that the software is faster than the traditional quoting system; however, the payback point is high. Also, results show the …
Production And Characterization Of Biodegradable Nanofibers Via Forcespinning™ Technology, Zachary T. Mceachin
Production And Characterization Of Biodegradable Nanofibers Via Forcespinning™ Technology, Zachary T. Mceachin
Theses and Dissertations - UTB/UTPA
Among the myriad of methods for polymer nanofiber production, there are only a few methods that can produce submicron range fibers in bulk from melt or solution samples. The Forcespinning™ method allows a substantial increase in sample yield; this greatly reduces the time needed to produce bulk quantities of fibers which may be critical in many fields of research and industry, in particularly in fields relating to biopolymers. The aim of the first study was to utilize this method to form non-woven mats of polycaprolactone (PCL) nanofibers and to quantitatively analyze the production and characterization of the produced fibers. The …
Implementation Of Wireless Temperature Sensors For Continuous Condition Monitoring Of Railroad Bearings, Andoni Zagouris Ii
Implementation Of Wireless Temperature Sensors For Continuous Condition Monitoring Of Railroad Bearings, Andoni Zagouris Ii
Theses and Dissertations - UTB/UTPA
At present there are no existing bearing health monitoring systems capable of continuous monitoring of railroad bearings. Current wayside equipment is used to collect intermittent bearing temperatures, which at times could be every 65 km (~40 mi). To answer this need, IONX, LLC, a subsidiary of Amsted Rail, Inc., has developed low power Wireless Sensor Nodes (WSNs) which can be retrofitted to existing bearing adapters. The WSNs provide continuous monitoring of bearing temperatures as well as the current ambient temperature. Since the nodes are affixed to the bearing adapter surface, a correlation is necessary to estimate the bearing cup temperature …
Development And Testing Of An Actively Adjustable Stiffness Mechanism, Eleazar Marquez, Robert Freeman, Horacio Vasquez
Development And Testing Of An Actively Adjustable Stiffness Mechanism, Eleazar Marquez, Robert Freeman, Horacio Vasquez
Mechanical Engineering Faculty Publications
This study presents the comparison of the theoretical and experimental results of the performance of an adjustable stiffness mechanism. In particular, the use of redundant actuation is emphasized in the design of a one degree-of-freedom Watt II mechanism capable of independently controlling the effective stiffness without a change in equilibrium position. This approach is in contrast to spring mechanism designs unable to actively control the spring rate independent of deflection, and with potential applications in various types of suspension and assembly systems. Results indicate that two direct drive brush-type direct current motors are required to drive the redundantly actuated mechanism …
Electrospun Carbon Nanofibers Decorated With Various Amounts Of Electrochemically-Inert Nickel Nanoparticles For Use As High-Performance Energy Storage Materials, Liwen Ji, Zhan Lin, Mataz Alcoutlabi, Ozan Toprakci, Yingfang Yao, Guanjie Xu, Shuli Li, Xiangwu Zhang
Electrospun Carbon Nanofibers Decorated With Various Amounts Of Electrochemically-Inert Nickel Nanoparticles For Use As High-Performance Energy Storage Materials, Liwen Ji, Zhan Lin, Mataz Alcoutlabi, Ozan Toprakci, Yingfang Yao, Guanjie Xu, Shuli Li, Xiangwu Zhang
Mechanical Engineering Faculty Publications
Carbon nanofibers decorated with various amounts of electrochemically-inert metallic nickel nanoparticles are synthesized through electrospinning and carbonization processes. The morphology and composition of Ni nanoparticles in carbon nanofibers are controlled by preparing different nanofiber precursors. The lithium-ion battery performance evaluations indicated that the content of electrochemically-inert Ni nanoparticles in carbon nanofibers has a great influence on the final electrochemical performance. For example, at certain Ni contents, these composite nanofibers display excellent electrochemical performance, such as high reversible capacities, good capacity retention, and excellent rate performance, when directly used as binder-free anodes for rechargeable lithium-ion batteries. However, when the Ni content …
An Investigation Into Temperature Trending In Railroad Tapered Roller Bearings Through Vibration Monitoring Techniques, Rafael Kristian Maldonado
An Investigation Into Temperature Trending In Railroad Tapered Roller Bearings Through Vibration Monitoring Techniques, Rafael Kristian Maldonado
Theses and Dissertations - UTB/UTPA
A series of laboratory experiments have been conducted at The University of Texas-Pan American to investigate the cause of bearing “temperature trending.” A combination of theoretical and experimental studies has identified potential sources for the abrupt changes in temperature often seen in railroad bearings. Previous studies suggest the possibility of vibration induced roller misalignment as the root cause for temperature trending. Subsequent research conducted by the UTPA team was designed to provide evidence through vibration monitoring techniques for the proposed hypothesis. To that end, a dynamic bearing tester was used to run four bearings at various speeds and loads experienced …
The Role Of Thermally-Induced Geometrical Changes In Temperature Trending Of Railroad Tapered Roller Bearings, Andrei G. Vaipan
The Role Of Thermally-Induced Geometrical Changes In Temperature Trending Of Railroad Tapered Roller Bearings, Andrei G. Vaipan
Theses and Dissertations - UTB/UTPA
The understanding of the phenomenon of temperature trending of railroad tapered roller bearings is of paramount importance to the railroad industry. The problem that this poses to the industry is that it leads to false alarms triggered by wayside detectors, which forces the premature removal of defect-free bearings. This thesis provides more insight into this phenomenon and answers questions regarding the importance of key tapered roller bearing components geometry and geometrical changes during temperature trending events. In this study, dynamic experiments conducted in the laboratory have represented the primary method of testing bearing temperature trending. The experimental results are brought …
Analysis And Design Of An Anisotropic, Compliant Suspension Component, Samantha Jean Salinas
Analysis And Design Of An Anisotropic, Compliant Suspension Component, Samantha Jean Salinas
Theses and Dissertations - UTB/UTPA
A steering pad on a train is meant to reduce the force on the wheel while moving along a curve in the rail. A new steering pad was desired with properties tuned for a new suspension system design. An anisotropic, compliant pad was designed for a specific stiffness anisotropy, 20:1. Finite element analysis was performed on various models as a guide to designing a pin with the desired stiffness ratio. A design was chosen for a prototype made of thermoset polyurethane, a similar material to that currently used. Experiments were performed on the prototype pad model to determine vertical and …
The Evaluation And Analysis Of The Impact Of Variability On The Twelve Workstation Factory, Hernando Garrido
The Evaluation And Analysis Of The Impact Of Variability On The Twelve Workstation Factory, Hernando Garrido
Theses and Dissertations - UTB/UTPA
Presently, there is theory and work examples about factory performance presented in the book ―Optimizing factory Performance‖ by James Ignizio, Ph.D. The theory explains how to determine performance using three fundamental equations by considering the impact and propagation of variability through a 12-Workstation Factory Model, and a number of its variations. The objective of developing a simulation model was to serve as a tool for instructors to illustrate the impact and propagation of variability in the manufacturing industry and to investigate phenomena (i.e., time to reach steady state, impact of variability) in the three dimensions of manufacturing. The validation of …
Development And Implementation Of Challenge-Based Instruction In Engineering Graphics, Gregory A. Potter
Development And Implementation Of Challenge-Based Instruction In Engineering Graphics, Gregory A. Potter
Theses and Dissertations - UTB/UTPA
This thesis discusses the challenge-based instructional (CBI) lessons currently being developed for the Engineering Graphics course at UTPA. This endeavor concentrates on student retention, as well as the students’ ability to practically apply their new skills. Minority science, technology, engineering, and math (STEM) students have been found, in recent studies, to depart from STEM undergraduate fields to some extent because of the lack of real world connections to the subject matter. Also, the traditional way of teaching theory first and then assigning a task may actually stifle creative thought and innovation required in later STEM courses. Our use of CBI …
Characterizing And Optimizing The Molten Salt Cleaning, Yangyang Long
Characterizing And Optimizing The Molten Salt Cleaning, Yangyang Long
Theses and Dissertations - UTB/UTPA
Molten salt cleaning is an important cleaning approach in remanufacturing which can remove a variety of contaminants from metal substrates with high efficiency. Facing the very limited research of this approach in literature, this thesis intends to characterize molten salt cleaning process and optimize its parameters when big parts with complicated shapes are cleaned. Based on the development of molten salt cleaning and studies on contaminations, two experiments are conducted. The first one investigates the influences of the hot salts on three metal substrates and shows the applicable of cleaning carbon steel and grey iron parts with molten salt. The …
Polarization Sensitive Near-Complete Reflection From Photonic Crystal Slab In Centered Rectangular Lattice, Simon Padron, Kris Ohlinger, Karen Lozano, Yuankun Lin
Polarization Sensitive Near-Complete Reflection From Photonic Crystal Slab In Centered Rectangular Lattice, Simon Padron, Kris Ohlinger, Karen Lozano, Yuankun Lin
Mechanical Engineering Faculty Publications
In this study, reflective properties have been systematically calculated for two-dimensional photonic crystal slabs in centered rectangular lattices with elliptical patterns for transverse electric polarization along perpendicular x- and y-directions. The slab structures can be geometrically optimized for a near-complete reflection over a broad wavelength range. The reflection from the photonic crystal slabs is polarization selective, allowing a complete reflection for one polarization and complete transmission for the other polarization, which could be useful for a laser cavity mirror without using Brewster windows. The dependence of the reflection on the slab thickness and the structural parameters demonstrates the effect of …