Engineering Commons^™

Front-End Cmos Transimpedance Amplifiers On A Silicon Photomultiplier Resistant To Fast Neutron Fluence, Mario Valles Montenegro

UNLV Theses, Dissertations, Professional Papers, and Capstones

Radiation hard electronics are indispensable in providing reliable diagnostics in fast radiation detection, which are necessary for new fundamental science research. In the case of radiation detection, transimpedance amplifiers are needed to magnify low photodetector signals to readable levels reliably. This thesis investigates a way to design a transimpedance CMOS-front-end transimpedance amplifier (TIA) as a first stage front-end amplifier. The TIA is to be mounted on silicon photomultiplier (SiPM), as a photodetector in fast neutron scintillation experiments capable of sustaining up to 10^15 n/cm of fast neutrons in the range of 0.1 to 20 MeV. The proposed TIA was designed …

On Action Quality Assessment, Paritosh Parmar

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation, we tackle the task of quantifying the quality of actions, i.e., how well an

action was performed using computer vision. Existing methods used human body pose-based features to express the quality contained in an action sample. Human body pose estimation in actions such as sports actions, like diving and gymnastic vault, is particularly challenging, since the athletes undergo convoluted transformations while performing their routines. Moreover, pose-based features do not take into account visual cues such as water splash in diving. Visual cues are taken into account by human judges. In our first work, we show that using …

Neural Network In Hardware, Jiong Si

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation describes the implementation of several neural networks built on a field programmable gate array (FPGA) and used to recognize a handwritten digit dataset – the Modified National Institute of Standards and Technology (MNIST) database. A novel hardwarefriendly activation function called the dynamic ReLU (D-ReLU) function is proposed. This activation function can decrease chip area and power of neural networks when compared to traditional activation functions at no cost to prediction accuracy.

The implementations of three neural networks on FPGA are presented: 2-layer online training fully-connected neural network, 3-layer offline training fully-connected neural network, and two solutions of Super-Skinny …

High-Speed Radhard Mega-Pixel Cis Camera For High-Energy Physics, Wenlan Wu

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation describes the schematic design, physical layout implementation, system-level hardware with FPGA firmware design, and testing of a camera-on-a-chip with a novel high-speed CMOS image sensor (CIS) architecture developed for a mega-pixel array. The novel features of the design include an innovative quadruple column-parallel readout (QCPRO) scheme with rolling shutter that increases pixel rate, its ability to program the frame rate and to tolerate Total Ionizing Dose effects (TID). Two versions of the architecture, a small (128 x 1,024 pixels) and large (768 x 1,024 pixels) version were designed and fabricated with a custom layout that does not include …

A Highly-Sensitive Global-Shutter Cmos Image Sensor With On-Chip Memory For Hundreds Of Kilo-Frames Per Second Scientific Experiments, Konstantinos Moutafis

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this work, a highly-sensitive global-shutter CMOS image sensor with on-chip memory that can capture up to 16 frames at speeds higher than 200kfps is presented. The sensor fabricated and tested is a 100 x 100 pixel sensor, and was designed to be expandable to a 1000 x 1000 pixel sensor using the same building blocks and similar architecture.

The heart of the sensor is the pixel. The pixel consists of 11 transistors (11T) and 2 MOSFET capacitors. A 6T front-end is followed by a Correlated Double Sampling (CDS) circuitry that includes 2 capacitors and a reset switch. The 4T …

The Effects Of Bone Morphogenic Protein 2 On The Viability And Proliferation Of Dental Pulp Stem Cell Isolates, Joseph Cinelli

UNLV Theses, Dissertations, Professional Papers, and Capstones

Growth factor is an umbrella term used to describe a signaling molecule present in organisms that serves the purpose of influencing a stimulatory or inhibitory response from the target cell it acts on. Growth factors are categorized and classified by the types of tissues they act on and the cellular responses they illicit. For example, there are growth factors that act primarily in connective tissue on fibroblasts and they are aptly classified as the fibroblast growth factor family. Similarly, there is another family of growth factors that act on bone forming cells, among others, and they are known as bone …

Analysis Of Bitcoin Cryptocurrency And Its Mining Techniques, Suman Ghimire

UNLV Theses, Dissertations, Professional Papers, and Capstones

Bitcoin is a peer-to-peer digital, decentralized cryptocurrency created by an individual under pseudonym Satoshi Nakamoto. In fact, it is the first digital, decentralized currency. Several developers and organizations have explored the importance of digital cryptocurrency and the concept of the blockchain. Bitcoin is assumed to be one of the secure and comfortable payment methods that can be used in the upcoming days. The backbone of Bitcoin mining is the concept of the blockchain, which is assumed to beone of the ingenious invention of this century. The blockchain is the collection of blocks that are linked together in such a way …

The Affective Perceptual Model: Enhancing Communication Quality For Persons With Pimd, Jadin Tredup

UNLV Theses, Dissertations, Professional Papers, and Capstones

Methods for prolonged compassionate care for persons with Profound Intellectual and Multiple Disabilities (PIMD) require a rotating cast of import people in the subjects life in order to facilitate interaction with the external environment. As subjects continue to age, dependency on these people increases with complexity of communications while the quality of communication decreases. It is theorized that a machine learning (ML) system could replicate the attuning process and replace these people to promote independence. This thesis extends this idea to develop a conceptual and formal model and system prototype.

The main contributions of this thesis are: (1) proposal of …

A Distributed Real-Time Short-Term Solar Irradiation Forecasting Network For Photovoltaic Systems, Michael Adelbert Gacusan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solar irradiation forecasting is essential for PV connected electrical grids to maintain reliability, stability, and effective matching of real-time demand to power distribution. This research paper develops and evaluates proposed forecasting methods using wireless sensor networks. Each node of the network is capable of monitoring illuminance data and communicate it through RF and/or WiFi. The nodes are calibrated with respect to irradiance data from an industry-standard pyranometer. Power consumption of each node type is also collected at different operating states. The proposed sensor network can estimate a cloud motion vector or a cloud shadow’s speed and direction from the data …

Design, Layout, And Testing Of Sige Apds Fabricated In A Bicmos Process, Dane Laurence Gentry

UNLV Theses, Dissertations, Professional Papers, and Capstones

This Thesis is concerned with the design, layout, and testing of avalanche photodiodes (APDs). APDs are a type of photodetector and, thus, convert light signals into electrical signals (current or voltage). APDs can be fabricated using silicon (Si). In this Thesis, however, three integrated circuit (IC) chips containing various silicon-germanium (SiGe) APDs with different sizes, structures, and geometries were designed, laid out, and fabricated using the Austriamicrosystems (AMS) 0.35μm SiGe BiCMOS (S35) process. This was done in order to compare SiGe APDs to Si only APDs and investigate the hypothesis that SiGe APDs are capable of detecting longer wavelengths than …

Variable Transition Time Inverters In A Digital Delay Line With Analog Storage For Processing Fast Signals And Pulses, James Kenton Mellott

UNLV Theses, Dissertations, Professional Papers, and Capstones

As the electronics industry moves forward there is an increasing need to process information faster and more accurately. High speed signals are used in scientific instrumentation, range finding devices, radar applications, and electro-optical interfaces. High-speed state of the art analog-to-digital converters are required to process these signals in real time. High frequency signals or very fast pulses are not able to be processed accurately due to either Nyquist-rate limitations or practical power consumption limits. For applications where signals are transient in nature and design size and power consumption are major factors, the proposed Variable Fast Transient Digitizer (VFTD) will be …

High Speed Fast Transient Digitizer Design And Simulation, Eric Clark Monahan

UNLV Theses, Dissertations, Professional Papers, and Capstones

In microelectronics, analog-to-digital converters (ADCs) are used as interfaces to convert analog inputs into discrete time or digital values that can be read via microcontrollers. As speed requirements and processing times in electronics continue to increase, high speed ADCs are increasingly critical components in the design of application-specific integrated circuits (ASICs). However, high speed ADCs introduce quantization error and are inefficient relative to size, cost, and power dissipation when compared to a High Speed Fast Transient Digitizer (HSFTD).

This thesis presents the design, layout, and simulation of a HSFTD designed to sample, in time at a fast rate, a high-speed …

Analysis And Design Of Analog Front-End Circuitry For Avalanche Photodiodes (Apd) And Silicon Photo-Multipliers (Sipm) In Time-Of-Flight Applications, Vikas Vinayaka

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis reports the analysis and design of analog front-end circuitry for reading out signals from avalanche photodiodes (APD) or silicon photomultiplier (SiPM) in time-of-flight (ToF) applications. An integrated circuit was designed using AMS SiGe 0.35 um BiCMOS process. The chip measured 2 mm x 2 mm (2000 umx2000 um). The chip mainly contains the following circuits: an APD with photoactive area measuring 24 umx24 um, an SiPM with 8x8 APDs with 236 k ohm quench resistors, a transimpedance amplifier (TIA), a comparator and a R-2R digital to analog converter (DAC). The TIA is based on the shunt-shunt feedback topology. …

Design And Analysis Of First And Second Order K-Delta-1-Sigma Modulators In Multiple Fabrication Processes, Shada Sharif

UNLV Theses, Dissertations, Professional Papers, and Capstones

Analog to digital converters (ADC) are an important category of electronic circuits that are required in order to convert real-world analog signals into the digital domain. One of the main trade-offs in ADC design is between data conversion speed and resolution. Delta Sigma ADCs are commonly used for high precision data conversion of low bandwidth signals such as those found in audio, industrial and biomedical applications. A major disadvantage of traditional Delta Sigma ADC architectures is that they have limited signal bandwidth and are not suited for high speed applications such as communication systems. The continuous time K-Delta-1-Sigma (KD1S) modulator …

Channel Estimation And Ici Cancelation In Vehicular Channels Of Ofdm Wireless Communication Systems, Vahid Vahidi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Orthogonal frequency division multiplexing (OFDM) scheme increases bandwidth efficiency (BE) of data transmission and eliminates inter symbol interference (ISI). As a result, it has been widely used for wideband communication systems that have been developed during the past two decades and it can be a good candidate for the emerging communication systems such as fifth generation (5G) cellular networks with high carrier frequency and communication systems of high speed vehicles such as high speed trains (HSTs) and supersonic unmanned aircraft vehicles (UAVs). However, the employment of OFDM for those upcoming systems is challenging because of high Doppler shifts. High Doppler …

Design & Delivery Of Automated Winston-Lutz Test For Isocentric & Off-Axis Delivery Stability Utilizing Truebeam Developer Mode & Electronic Portal Imaging Device, Mahmoud Mohammad Yaqoub

UNLV Theses, Dissertations, Professional Papers, and Capstones

The uncertainties in treatment delivery cannot be ignored in radiation therapy. Thus, the quality assurance QA tests are very important task of the medical physicist in clinical practice. Assuring the coincidence between the mechanical isocenter of the Linear Accelerator (LINAC) and its radiation beams isocenter is one of the most important qualities need to be tested, and the Winston Lust (WL) test is the

most popular technique to perform this task, especially for the treatment modalities which need high precision in beam delivery such as the stereotactic radiosurgery/stereotactic body radiotherapy (SRS/SBRT). The linear accelerator-based SRS/SBRT is a well-established method in …

Affinity Points In Variable Frequency Drive – Motor Systems, Christophe Hicks

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis work will quantify power flow characteristics of variable frequency drive (VFD) systems at utilization voltages (208V3 phase) under normal and abnormal operating conditions. Abnormal operating conditions are defined in this thesis work as over or under

voltages at or exceeding 10% of the nominal rated voltage for 1sec to 10sec durations. Motivation and direction towards efficient power use has produced new devices which can be implemented at utilization voltage levels. Those devices are designed to modernize use

through efficient energy consumption. Existing system planning methodologies incorporate larger VFD motor system (>4160V) dynamics and lump lower voltage levels …

The Combined Effect Of Photovoltaic And Electric Vehicle Penetration On Conservation Voltage Reduction In Distribution System, Narayan Bhusal

UNLV Theses, Dissertations, Professional Papers, and Capstones

Global conditions over the past dozen years have led to an expanded appetite for renewable energy sources: The diminishing fossil fuel supply, the political instability of countries producing these fossil fuels, the ever-more destructive effects of global warming, and the lowering of costs for renewable energy technologies have made countries around the world reconsider their sources of energy. The proliferation of photovoltaic (PV) systems especially has surged dramatically with the decreasing initial costs for installation, and increasing government support in the form of renewable energy portfolios, feed-in-tariffs,

tax incentives, etc. Furthermore, electric vehicles (EV) are also becoming widespread due to …

Design On High Performance Nanoscale Cmos Circuits With Low Temperature Sensitivity, Ming Zhu

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the rapid development of integrated circuit (IC) design and manufacturing technology, the transistor size now can be shrunk into only couple of nanometers whereas billions of transistors can be squeezed into a square millimeter, providing unprecedented computation power. However, accompanied with continuous device miniaturization and increased integration density is the explosive growth of on-chip power dissipation and a wide range of temperature fluctuation, which can heavily and negatively affect the delay performance of the circuit, or in the worst case, the circuit may malfunction and the system can be unreliable. Therefore, improved performance resilience against temperature variations has become …

Linear And Nonlinear Adaptive Attitude Control Of Asteroid-Orbiting Spacecraft Using State Feedback And Output Feedback, Nicholas Moya

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents the derivation of both a linear and nonlinear adaptive control law for the attitude states of a spacecraft in orbit around rotating asteroids. The asteroid is assumed to be irregularly shaped and in an elliptical orbit around the sun. The linearized, time-varying spacecraft model will assume to include unknown parameters and will have external disturbances present. The objective is to control the roll, pitch, and yaw angle trajectories of the spacecraft such that they track desired reference trajectories. To achieve this, the control law will be composed of (1) a feedback controller, sufficiently robust to disturbance such …

Parents' Perceptions Of Smartphone Use And Parenting Practices, David Jackson Johnson

UNLV Theses, Dissertations, Professional Papers, and Capstones

The present study is a qualitative examination aiming to gain insight into parents’ perceptions of their smartphone use and the effects it may be having on their children as well as parenting practices. Participants (N=12) were smartphone using parents that consisted mostly of young college-educated females. Thematic analysis of individual interviews resulted in five primary themes: (1) Disengagement, (2) Concern for Future, (3) Change in Social Norms, (4) Boundaries, and (5) Cognitive Dissonance. These findings indicate significant effects parental smartphone use is having in the lives of study participants. These thematic findings call for additional research examining the impact parental …

Improving Hyperspectral Subpixel Target Detection Using Hybrid Detection Space, Ruixing Li

UNLV Theses, Dissertations, Professional Papers, and Capstones

A Hyper-Spectral Image (HSI) has high spectral and low spatial resolution. As a result, most targets exist as subpixels, which pose challenges in target detection. Moreover, limitation of target and background samples always hinders the target detection performance. In this thesis, a hybrid method for subpixel target detection of an HSI using minimal prior knowledge is developed. The Matched Filter (MF) and Adaptive Cosine Estimator (ACE) are two popular algorithms in HSI target detection. They have different advantages in differentiating target from background. In the proposed method, the scores of MF and ACE algorithms are used to construct a hybrid …

Simulating Distributed Battery And Solar Array Placement For Voltage Regulation, Michael Misch

UNLV Theses, Dissertations, Professional Papers, and Capstones

Energy storage has been around for many years in the US, mainly in the form of pumped hydro. However, in recent years, other storage technologies have developed quickly, with lithium ion batteries receiving significant investment and delivering technological and price improvements. Electricity storage has the potential to assist the US in transitioning to a smarter grid, as well as enabling increasing amounts of renewable generation to connect to the grid, without costly reinforcement works. Electricity storage can be co-located with power generation assets, installed along distribution systems for network services, or placed behind the meter, i.e., on the customer’s premises. …

Optimization Of Prosthetic Hands: Utilizing Modularity To Improve Grip Force, Grasp, And Versatility, Jordan William Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

It has been demonstrated that although many varieties of upper limb prosthetics exist, commercially available prosthetics are outdated and unsatisfactory. Ineffectiveness and limitations have led to some prosthesis wearers having to own multiple devices, whereas others have given up on them entirely. Even though ample research has been conducted to design and test new hand designs, the industry appears to rest in an overall stagnated state.

It was proposed here, that one problem with prosthetic research is an excess of variables involved in testing, and therefore the improper application of the scientific method. It seems that each time a research …

Cyclist Detection, Tracking, And Trajectory Analysis In Urban Traffic Video Data, Farideh Foroozandeh Shahraki

UNLV Theses, Dissertations, Professional Papers, and Capstones

The major objective of this thesis work is examining computer vision and machine learning detection methods, tracking algorithms and trajectory analysis for cyclists in traffic video data and developing an efficient system for cyclist counting. Due to the growing number of cyclist accidents on urban roads, methods for collecting information on cyclists are of significant importance to the Department of Transportation. The collected information provides insights into solving critical problems related to transportation planning, implementing safety countermeasures, and managing traffic flow efficiently. Intelligent Transportation System (ITS) employs automated tools to collect traffic information from traffic video data. In comparison to …

Automated Quantification Of White Blood Cells In Light Microscopic Images Of Injured Skeletal Muscle, Yang Jiao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Muscle regeneration process tracking and analysis aim to monitor the injured muscle tissue section over time and analyze the muscle healing procedure. In this procedure, as one of the most diverse cell types observed, white blood cells (WBCs) exhibit dynamic cellular response and undergo multiple protein expression changes. The characteristics, amount, location, and distribution compose the action of cells which may change over time. Their actions and relationships over the whole healing procedure can be analyzed by processing the microscopic images taken at different time points after injury. The previous studies of muscle regeneration usually employ manual approach or basic …

Sparse Mri And Ct Reconstruction, Ali Pouryazdanpanah Kermani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Sparse signal reconstruction is of the utmost importance for efficient medical imaging, conducting accurate screening for security and inspection, and for non-destructive testing. The sparsity of the signal is dictated by either feasibility, or the cost and the screening time constraints of the system. In this work, two major sparse signal reconstruction systems such as compressed sensing magnetic resonance imaging (MRI) and sparse-view computed tomography (CT) are investigated.

For medical CT, a limited number of views (sparse-view) is an option for whether reducing the amount of ionizing radiation or the screening time and the cost of the procedure. In applications …

Deployment Strategies For A Fleet Of Unmanned Aerial Vehicles Providing Cellular And Data Services, Nima Mohseni

UNLV Theses, Dissertations, Professional Papers, and Capstones

Wireless voice and data communications have become an essential part of our day to day lives. In order to provide these services to as many people as possible, a great infrastructure has been put in place over the last two decades throughout the world. The current infrastructure is mainly consists of cellular towers with gateways to the telecommunication backbone. The wireless infrastructure is doing an adequate job of providing voice and data services, getting more powerful and efficient every day. However, because wireless infrastructure is mainly based on fixed cell towers, it lacks the flexibility and dynamism that may be …

Analog And Mixed Signal Verification Using Satisfiability Solver On Discretized Models, Nikita Ramesh Wanjale

UNLV Theses, Dissertations, Professional Papers, and Capstones

With increasing demand of performance constraints and the ever reducing size of the IC chips, analog and mixed-signal designs have become indispensable and increasingly complex in modern CMOS technologies. This has resulted in the rise of stochastic behavior in circuits, making it important to detect all the corner cases and verify the correct functionality of the design under all circumstances during the earlier stages of the design process. It can be achieved by functional or formal verification methods, which are still widely unexplored for Analog and Mixed-Signal (AMS) designs.

Design Verification is a process to validate the performance of the …

Novel Methods For The Time-Dependent Maxwell’S Equations And Their Applications, Sidney Shields

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation investigates three different mathematical models based on the time domain Maxwell's equations using three different numerical methods: a Yee scheme using a non-uniform grid, a nodal discontinuous Galerkin (nDG) method, and a newly developed discontinuous Galerkin method named the weak Galerkin (WG) method. The non-uniform Yee scheme is first applied to an electromagnetic metamaterial model. Stability and superconvergence error results are proved for the method, which are then confirmed through numerical results. Additionally, a numerical simulation of backwards wave propagation through a negative-index metamaterial is given using the presented method. Next, the nDG method is used to simulate …