Engineering Commons^™

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

Parametric Study Of Residual Stresses In Wire And Arc Additive Manufactured Parts, Hisham Khaled Jamil Abusalma

Mechanical & Aerospace Engineering Theses & Dissertations

Wire and Arc Additive Manufacturing (WAAM) is a cost-effective additive manufacturing process due to its capability to fabricate large metal parts with high deposition rate and low equipment cost. Although this method is gaining popularity in manufacturing industry, more research is needed to understand process parameters’ effects on residual stress (RS) distribution and part distortion. As such, a 3D thermo-elastic-plastic transient model was established in ABAQUS and employed to investigate the effect of process parameters such as the torch speed, the deposition power and the interlayer dwell time on RS distribution and distortion in WAAM part. The numerical model utilized …

Docs_On_Blocks – A Defense In Depth Strategy For E-Healthcare, Saad Mohammed

Electronic Theses, Projects, and Dissertations

With the increase in the data breaches and cyber hacks, organizations have come to realize that cyber security alone would not help as the attacks are becoming more sophisticated and complex than ever. E-Healthcare industry has shown a promising improvement in terms of security over the past, but the threat remains. Thus, the E-Healthcare industries are aiming towards a Defense in Depth Strategy approach.

The project here describes how a Defense in Depth Strategy for E-Healthcare system can provide an environment for better security of the data and peer-to-peer interaction with stakeholders. The legacy systems have at some point failed …

Deep Reinforcement Learning For Collaborative Edge Computing In Vehicular Networks, Mushu Li, Jie Gao, Lian Zhao, Xuemin Shen

Electrical and Computer Engineering Faculty Research and Publications

Mobile edge computing (MEC) is a promising technology to support mission-critical vehicular applications, such as intelligent path planning and safety applications. In this paper, a collaborative edge computing framework is developed to reduce the computing service latency and improve service reliability for vehicular networks. First, a task partition and scheduling algorithm (TPSA) is proposed to decide the workload allocation and schedule the execution order of the tasks offloaded to the edge servers given a computation offloading strategy. Second, an artificial intelligence (AI) based collaborative computing approach is developed to determine the task offloading, computing, and result delivery policy for vehicles. …

Development Of Functional Materials And Devices On Flexible Platforms Using Additive Print Manufacturing Processes For Biomedical And Environmental Applications, Dinesh Maddipatla

Dissertations

In recent years, considerable research has been vested into the development of printed electronics (PE) to explore the best ways of fabricating electronic devices on flexible platforms using additive print manufacturing processes. PE produces flexible devices that are compatible with complex geometries, foldable applications and conformal to curved surfaces, with a promising potential for large‐area device fabrication at relatively lower manufacturing costs. This dissertation focuses majorly on the design and fabrication of novel flexible functional materials and devices for biomedical and environmental applications using additive printing processes.

Initially, a simple paper-based low cost and rapid prototypable platform with oxygen sensors …

Ppmexplorer: Using Information Retrieval, Computer Vision And Transfer Learning Methods To Index And Explore Images Of Pompeii, Cindy Roullet

Graduate Theses and Dissertations

In this dissertation, we present and analyze the technology used in the making of PPMExplorer: Search, Find, and Explore Pompeii. PPMExplorer is a software tool made with data extracted from the Pompei: Pitture e Mosaic (PPM) volumes. PPM is a valuable set of volumes containing 20,000 historical annotated images of the archaeological site of Pompeii, Italy accompanied by extensive captions. We transformed the volumes from paper, to digital, to searchable. PPMExplorer enables archaeologist researchers to conduct and check hypotheses on historical findings. We present a theory that such a concept is possible by leveraging computer generated correlations between artifacts using …

Atmospheric Turbulence Distortion In Video: Restoration Utilizing Sparse Analysis, Benjamin J. Sanda

Dissertations

The removal of atmospheric turbulence (AT) distortion in long range imaging is one of the most challenging areas of research in imaging processing with an immediate need for solutions in several applications such as in military and transportation systems. AT exacerbates distortion due to non-linear geometric blur and scintillations in long-distance images and videos, severely reducing image quality and information interpretation. AT negatively impacts both human and computer vision systems, compromising visibility essential for accurate object identification and tracking.

In this dissertation, a novel sparse analysis framework is developed to address efficient AT blur and scintillation removal in video. Operating …

Objectively Determining The Language-Related Communication Challenges For In-Flight Operations, Fehime Utkan

Dissertations

Communication breakdowns between pilots and air traffic controllers (ATCs) have been identified as primary factors in fatal airplane accidents (Wu et. al., 2019; Bauh & Stolzer, 2018; Ritter, 1996; Eurocontrol, 2011). Although there are various aspects that have affected communication efficiency, language-related issues have been mostly associated with transmissions involved in serious incidents, especially in multicultural flight environments (Sexton & Helmrich, 2000). More than 2,000 people have died in accidents where miscommunication was a primary factor (Bauh & Stolzer, 2018; Patty, 2016). By the year of 2025, the air transportation system is projected to become more complex, and the volume …

Flight Tests Of Trajectory Energy Management Systems Using A Vertical Takeoff And Landing Vehicle, Emils Senkans

Theses and Dissertations

The rise of new aircraft propulsion methods (e.g. powered by batteries, fuel cells or hybrid electric systems), the increased use of automated and integrated flight control systems, and the envisioned use of personal Vertical Takeoff and Landing (VTOL) vehicles in urban environments (urban aerial mobility) leads to novel technical and regulatory challenges for aircraft manufacturers, certification authorities and operators. Of primary concern is operational safety, and closely connected pilot situation awareness and workload. A particular safety factor for operating VTOL vehicles that depend on propulsive lift for the majority of their operations and that are operated over urban terrain, is …

Test And Evaluation Of An Artec Leo 3d Scanner, Chelsea Alexis Reichard

Theses and Dissertations

With new and innovative technologies, companies have begun utilizing 3-Dimensional Scanners to reverse engineer objects of virtually any size or complexity. These scanners increase efficiency, allowing companies to import physical items into the computer without the hassle of modeling it themselves in Computer Aided Design (CAD) software. Although these highly advanced devices can be very fast and effective, we will be studying the surfaces that are incompatible to these scanners. The study performed in this research will test the limitations of a new, highly advanced, wireless 3D Scanner; The Artec Leo. For many scanners, including the one used in this …

Efficient Edge Analytics: Addressing Cyber-Physical Masint With Machine Learning On Audio At The Edge, David Elliott

Theses and Dissertations

With the growth of the Internet of Things and the rise of Big Data, data processing and machine learning applications are being moved to cheap and low size, weight, and power (SWaP) devices at the edge, often in the form of mobile phones, embedded systems, or microcontrollers. The field of Cyber-Physical Measurements and Signature Intelligence (MASINT) makes use of these devices to analyze and exploit data in ways not otherwise possible, which results in increased data quality, increased security, and decreased bandwidth. However, methods to train and deploy models at the edge are limited, and models with sufficient accuracy are …

Cloud Computing Service Interoperability And Architectural Concepts, Anmar Salih

Theses and Dissertations

Today’s market with a vast number of Cloud-computing providers creates a challenge for practical cooperation between the various provider cloud service platforms. Not only does Cloud interoperability provide this needed cooperation, but it also avoids vendor lock-in and, additionally, saves time and cost. Although there is no established definition for Cloud interoperability, most researchers agree on the purposes of Cloud interoperability. Research and literature have attempted to explain interoperability as transferring data, moving workloads, and migrating virtual machines between Cloud platforms. Transferring data between Clouds refers to objects migrating between provider-specific domains. In comparison, data migration is the most commonly …

Development Of Nirs Based Noninvasive Cerebrovascular Regulation Assessment, Stephanie Marie Miller

Theses and Dissertations

Alterations to cerebral blood flow (CBF) have been implicated in diverse neurological conditions, including mild traumatic brain injury, microgravity induced intracranial pressure (ICP) and intraocular pressure (IOP) increases, and mild cognitive impairment. Near infrared spectroscopy (NIRS)-measured regional cerebral tissue oxygen saturation (rSO2) provides an estimate of oxygenation of the interrogated cerebral volume that is useful in identifying trends and changes in oxygen supply to cerebral tissue and has been used to monitor cerebrovascular function during surgery and ventilation. In this study, CO2-inhalation-based hypercapnic breathing challenges were used as a tool to simulate CBF dysregulation, and NIRS was used to monitor …

Label-Free Optical Biomarkers Detect Early Calcific Aortic Valve Disease In A Wild-Type Mouse Model, Ishita Tandon, Shelby Johns, Alan Woessner, Jessica Perez, Delaney Cross, Asya Ozkizilcik, Timothy Muldoon, Srikanth Vallurupalli, Muralidhar Padala, Kyle P. Quinn, Kartik Balachandran

Biomedical Engineering Faculty Publications and Presentations

Background

Calcific aortic valve disease (CAVD) pathophysiology is a complex, multistage process, usually diagnosed at advanced stages after significant anatomical and hemodynamic changes in the valve. Early detection of disease progression is thus pivotal in the development of prevention and mitigation strategies. In this study, we developed a diet-based, non-genetically modified mouse model for early CAVD progression, and explored the utility of two-photon excited fluorescence (TPEF) microscopy for early detection of CAVD progression. TPEF imaging provides label-free, non-invasive, quantitative metrics with the potential to correlate with multiple stages of CAVD pathophysiology including calcium deposition, collagen remodeling and osteogenic differentiation.

Methods …

Noise And Detectivity Limits In Organic Shortwave Infrared Photodiodes With Low Disorder, Zhenghui Wu, Ning Li, Naresh Eedugurala, Jason D. Azoulay, Dong Seok Leem, Tse Nga Ng

Faculty Publications

© 2020, The Author(s). To achieve high detectivity in infrared detectors, it is critical to reduce the device noise. However, for non-crystalline semiconductors, an essential framework is missing to understand and predict the effects of disorder on the dark current. This report presents experimental and modeling studies on the noise current in exemplar organic bulk heterojunction photodiodes, with 10 donor–acceptor combinations spanning wavelength between 800 and 1600 nm. A significant reduction of the noise and higher detectivity were found in devices using non-fullerene acceptors (NFAs) in comparison to those using fullerene derivatives. The low noise in NFA blends was attributed …

Large Eddy Simulation Of Turbidity Currents In A Narrow Channel With Different Obstacle Configurations, Danial Goodarzi, Kaveh Sookhak Lari, Ehsan Khavasi, Soroush Abolfathi

Research outputs 2014 to 2021

© 2020, The Author(s). Turbidity currents are frequently observed in natural and man-made environments, with the potential of adversely impacting the performance and functionality of hydraulic structures through sedimentation and reduction in storage capacity and an increased erosion. Construction of obstacles upstream of hydraulic structures is a common method of tackling adverse effects of turbidity currents. This paper numerically investigates the impacts of obstacle’s height and geometrical shape on the settling of sediments and hydrodynamics of turbidity currents in a narrow channel. A robust numerical model based on LES method was developed and successfully validated against physical modelling measurements. This …

Sequential Damage Study Induced In Fiber Reinforced Composites By Shear And Tensile Stress Using A Newly Developed Arcan Fixture, Israr Ud Din, Shanshan Tu, Pei Hao, Stéphane Panier, Kamran Ahmed Khan, Rehan Umer, Syed Z. H. Shah, Gérald Franz, Muhammad Aamir

Research outputs 2014 to 2021

This work presents the application of both uniaxial and bi-axial in-plane loads to unidirectional carbon fiber reinforced polymer laminates using a newly developed Arcan fixture, which is a reliable experimental set-up to obtain a uniform shear stress field in a butterfly specimen. The set-up can be used for both damage model validation and parameters identification at various fiber orientations while using the same specimens. A sequential damage study was completed to highlight the influence of diffused damage induced in pure shear on the fiber direction tensile behavior of the laminate. This was accomplished by applying load on the specimens in …

Homotopy Simulation Of Dissipative Micropolar Flow And Heat Transfer From A Two-Dimensional Body With Heat Sink Effect: Applications In Polymer Coating, O. A. Bég, B. Vasu, A. K. Ray, T. A. Beg, A. Kadir, H. J. Leonard, Rama S. R. Gorla

Faculty Publications

Non-Newtonian flow from a wedge constitutes a fundamental problem in chemical engineering systems and is relevant to processing of polymers, coating systems, etc. Motivated by such applications, the homotopy analysis method (HAM) was employed to obtain semi-analytical solutions for thermal convection boundary layer flow of incompressible micropolar fluid from a two-dimensional body (wedge). Viscous dissipation and heat sink effects were included. The non-dimensional boundary value problem emerges as a system of nonlinear coupled ordinary differential equations, by virtue of suitable coordinate transformations. The so-called Falkner-Skan flow cases are elaborated. Validation of the HAM solutions was achieved with earlier simpler models, …

Ventilation And Recirculation Airway Design For An Autonomous, Climate Controlled, Hydroponic Demonstration Unit, Nicholas Cross

Biological and Agricultural Engineering Undergraduate Honors Theses

For this Honors Thesis project, I designed and fabricated a ventilation and recirculation airway sub-system prototype for a hydroponic demonstration unit to be used as an educational demonstration for prospective students, illustrating the capabilities of biological engineers. This thesis focuses on the design of an autonomous air system that toggles between ventilation and recirculation modes based upon sensor output. In the literature review I discuss how ventilation can be used to achieve a targeted climate, the benefits of hands-on projects for education, and the optimum parameters for growing herbs in a hydroponic system.

In the design and fabrication process, every …

Defect Evolution In High-Temperature Irradiated Nuclear Graphite, Steve Johns

Boise State University Theses and Dissertations

Graphite has historically been used as a moderator material in nuclear reactor designs dating back to the first man-made nuclear reactor to achieve criticality (Chicago Pile 1) in 1942. Additionally, graphite is a candidate material for use in the future envisioned next-generation nuclear reactors (Gen IV); specifically, the molten-salt-cooled (MSR) and very-high-temperature reactor (VHTR) concepts. Gen IV reactor concepts will introduce material challenges as temperature regimes and reactor lifetimes are anticipated to far exceed those of earlier reactors. Irradiation-induced defect evolution is a fundamental response in nuclear graphite subjected to irradiation. These defects directly influence the many property changes of …

Direct Solar Absorption Nanoparticle Doped Membranes For A Hybrid Membrane Distillation And Photovoltaic Cell, Alejandro Espejo Sanchez

Boise State University Theses and Dissertations

The growing demand for clean water supplies is driving the need for an innovative approach of water desalination. Developing a method for treating water with high salinities is possible with membrane distillation (MD). Additionally, MD is very attractive for pairing with solar energy due to the low temperature requirements. The integration of a membrane distillation system with a photovoltaic (PV) system will result in the co-production of electricity and clean water, thereby improving the economics of MD. Such a hybrid system will directly absorb thermal energy in the membrane for desalination while taking advantage of the spectrally selective nature of …

Additive Manufacturing Of Graphene-Based Devices For Flexible Hybrid Electronics, Twinkle Pandhi

Boise State University Theses and Dissertations

In this work, I investigate and enhance the fundamental sensing properties of printed electronic nanomaterials (e.g., graphene) in real-world environments while decreasing weight, cost, and power consumption. The dissertation addresses this issue with the following foci in mind: (1) developing a straightforward and repeatable process to synthesize graphene ink which is also compatible with Inkjet-printing (IJP) and Aerosol Jet printing (AJP). (2) Tuning additive manufacturing printing (IJP and AJP) parameters to establish a repeatable manufacturing process and print high performing (graphene-based) electrodes and interconnects, compatible with the underlying substrate. (3) Investigate power dissipation and electrical breakdown in AJP printed graphene …

Constitutive Modeling Of Force-Controlled Fatigue Testing In Human Meniscus Tissue, Bradley Scott Henderson

Boise State University Theses and Dissertations

The meniscus is a wedge-shaped fibrocartilaginous tissue located between the femur and tibia that helps stabilize the knee and protect the underlying cartilage. There are 2.5 million reported knee injuries each year, making it the most injured joint in the human body. Nearly twenty percent of these injuries are due to a torn meniscus, leading to over half a million meniscus surgeries performed in the United States annually. Therefore, it is critical to understand the failure modes of meniscus tissue to prevent these debilitating injuries. A failure mode that accounts for one-third of all meniscus injuries is repeated exposure to …

Large Displacement J-Integral Double Cantilever Beam (Dcb) Test Method For Mode I Fracture Toughness, Joshua Gunderson

Boise State University Theses and Dissertations

The J-integral is used to develop an alternative double cantilever beam (DCB) test method for the Mode I fracture toughness suitable for both small and large displacements. The current focus is the experimental determination of the Mode I interlaminar fracture toughness of composite materials, but the method is generally applicable to other similar tests and material systems, such as to the Mode I fracture toughness of adhesives. A series of five identical specimens are tested to compare the linear-elastic fracture mechanics method recommended by ASTM, which makes use of linear beam theory with root rotation, large displacement, and end …

Designing And Evaluating Of Mimo Systems For Millimeter-Wave Communications, Mojtaba Ahmadi Almasi

Boise State University Theses and Dissertations

The fifth generation (5G) of wireless communications will integrate all existing technologies while bringing its own to the system. Amongst these technologies, millimeter-wave (mmWave) is emerging as a promising solution for 5G systems. However, to fully harness the potential of mmWave communications, obstacles such as severe path loss, channel sparsity, and hardware complexity should be overcome. The existing cost-effective systems can considerably reduce the hardware complexity and partially severe path loss, while channel sparsity still remains a main problem. Other factors such as transmission reliability and coverage area should be considered in 5G mmWave communications. Non-orthogonal multiple access (NOMA) is …

Understanding Mesoscopic Chemo-Mechanical Distress And Mitigation Mechanisms Of Concrete Subject To Asr, Md Asif Rahman

Boise State University Theses and Dissertations

Alkali-silica reaction (ASR) is one of the common sources of concrete damage worldwide. The surrounding environment, namely, temperature and humidity greatly influence the alkali-silica reaction induced expansion. Global warming (GW) has caused frequent change in the climate and initiated extreme weather events in recent years. These extreme events anticipate random change in temperature and humidity, and convey potential threats to the concrete infrastructure. Moreover, external loading conditions also affect the service life of concrete. Thus, complex mechanisms of ASR under the impact of seasonal change and global warming require a precise quantitative assessment to guide the durable infrastructure materials design …

In Vitro Method To Quantify And Visualize Volumetric Wear In Meniscus Subjected To Joint Loading Using A 3d Optical Scanner, Kate J. Benfield

Boise State University Theses and Dissertations

The menisci are fibrocartilaginous soft tissues that act to absorb and distribute load across the surface of the knee joint. As a result of mechanical wear and large repetitive loading, meniscus tissue can begin to breakdown, or degenerate. Meniscus degeneration increases the risk of tearing, weakened tissue integrity, and the progression of osteoarthritis. Therefore, it is imperative to understand the wear behavior of whole human meniscus to identify conditions that may significantly increase the risk of degeneration.

The objective of this study is to develop and validate an in vitro methodology for characterizing volumetric wear behavior in whole human meniscus …

Current-Mode Photon-Counting Circuit With Sige Bicmos Input Stage, Gonzalo Guadalupe Arteaga

UNLV Theses, Dissertations, Professional Papers, and Capstones

Continued advances in photodetector technology have helped improve the imaging capabilities of LiDAR systems or other time-of-flight imaging efforts. As a major part of the receiver within a LiDAR system, the photodetector can offer features such as faster rise times, narrower pulse widths, or larger gains to help achieve greater timing resolution or sensitivity to faint light levels. These benefits, however, are contingent on the ability of the accompanying readout circuit to reliably process the fast, electrical signals generated by the photodetector. While common front-end circuits involve the use of feedback amplifiers, their stability can become a major concern at …

Validation Of Novel Obstructive Sleep Apnea Treatment With Silicone Gel Experimental Models, Dustin Walter Burd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Predictive modeling to increase treatment success rates for surgical procedures is becoming more common in the scientific community. For obstructive sleep apnea (OSA), modeling has been predominately performed using computers as opposed to experimental models. Computer simulation saves time by eliminating the need to fabricate complex experimental models but comes at the expense of insight gained through physical observations made in real time. Experimental models for studying OSA are needed to validate computational work, provide perspective on anatomical scale and demonstrate complex deformations in real time. This work addresses prior hurdles in experimental model fabrication with a novel process using …

Salt Transport To Saturated Porous Media Under Unstable Conditions: Experimental, Analytical, And Numerical Studies, Kamal Mamoua

Theses and Dissertations

There are three main transport mechanisms that occur under unstable flow conditions: a) The transport of saltwater from the overlying salt source to the underlying porous media, b) the transport of an equivalent volume of displaced groundwater from the porous media into the source, and c) the transport of the saltwater through the porous media. In many situations; such as, estuaries, salt lakes, and landfills, it may be necessary to determine the rate of saltwater transport from an overlying unstable salt source that has heavier saline water overlying porous media fully saturated by lighter saline water. Studies of unstable density …