Computer Engineering Commons^™

Parallel For Loops On Heterogeneous Resources, Frederick Edward Weber

Doctoral Dissertations

In recent years, Graphics Processing Units (GPUs) have piqued the interest of researchers in scientific computing. Their immense floating point throughput and massive parallelism make them ideal for not just graphical applications, but many general algorithms as well. Load balancing applications and taking advantage of all computational resources in a machine is a difficult challenge, especially when the resources are heterogeneous. This dissertation presents the clUtil library, which vastly simplifies developing OpenCL applications for heterogeneous systems. The core focus of this dissertation lies in clUtil's ParallelFor construct and our novel PINA scheduler which can efficiently load balance work onto multiple …

Kernel-Assisted And Topology-Aware Mpi Collective Communication Among Multicore Or Many-Core Clusters, Teng Ma

Doctoral Dissertations

Multicore or many-core clusters have become the most prominent form of High Performance Computing (HPC) systems. Hardware complexity and hierarchies not only exist in the inter-node layer, i.e., hierarchical networks, but also exist in internals of multicore compute nodes, e.g., Non Uniform Memory Accesses (NUMA), network-style interconnect, and memory and shared cache hierarchies.

Message Passing Interface (MPI), the most widely adopted in the HPC communities, suffers from decreased performance and portability due to increased hardware complexity of multiple levels. We identified three critical issues specific to collective communication: The first problem arises from the gap between logical collective topologies and …

Extending Structural Learning Paradigms For High-Dimensional Machine Learning And Analysis, Christopher Todd Symons

Doctoral Dissertations

Structure-based machine-learning techniques are frequently used in extensions of supervised learning, such as active, semi-supervised, multi-modal, and multi-task learning. A common step in many successful methods is a structure-discovery process that is made possible through the addition of new information, which can be user feedback, unlabeled data, data from similar tasks, alternate views of the problem, etc. Learning paradigms developed in the above-mentioned fields have led to some extremely flexible, scalable, and successful multivariate analysis approaches. This success and flexibility offer opportunities to expand the use of machine learning paradigms to more complex analyses. In particular, while information is often …

Dynamic Task Execution On Shared And Distributed Memory Architectures, Asim Yarkhan

Doctoral Dissertations

Multicore architectures with high core counts have come to dominate the world of high performance computing, from shared memory machines to the largest distributed memory clusters. The multicore route to increased performance has a simpler design and better power efficiency than the traditional approach of increasing processor frequencies. But, standard programming techniques are not well adapted to this change in computer architecture design.

In this work, we study the use of dynamic runtime environments executing data driven applications as a solution to programming multicore architectures. The goals of our runtime environments are productivity, scalability and performance. We demonstrate productivity by …

Using Player Profiling To Enhance Dynamic Difficulty Adjustment In Video Games, Aaron Burke

Computer Engineering

Video games have certainly come a long way since the days of pong. From humble beginnings of the first arcade machines they have bloomed into a multi-billion dollar industry and a global force to be reckoned with. Just like with movies there are enough genres out there to fit any demographic of gamer, and that’s not even just the game’s content but also the gameplay.

Unlike other types of media though, games are meant to be interacted with and played, which brings up new issues with accessibility and keeping things interesting for different levels of skill. Dynamic game difficulty adjustment …

The Quickiecomposer Android Application, Brigit Elizabeth Hawley

Liberal Arts and Engineering Studies

The QuickieComposer application is a program intended for use on Android Devices. Designed for the composer on the go, the QuickieComposer app is perfect for those “in the moment” compositions. In the following document, the functionality and development of the first version of the QuickieComposer application is explained.

Image Segmentation For Quantification Of Air-Water Interface In Micro-Ct Soil Images, Kranthi Kumar Potteti

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soils are complex environments comprising various biological (roots, water, air etc) and physical constituents (minerals, aggregates, etc). Synchrotron radiation based X-ray microtomography (XMT) is widely used in extracting qualitative and quantitative information regarding spatial distribution of biological and physical soil constituents. Segmentation of these micro-CT soil images is of interest to geologists, hydrologists, civil and petroleum engineers and soil scientists. In this present work, we study and implement segmentation algorithms for microhydrology studies, specifically for soil water conductivity. Three well-known image segmentation algorithms are studied for evaluating their performance for the task. We demonstrate the problems and ways to segment …

Thin 3d Multiplication Regions In Plasmonically Enhanced Nanopillar Avalanche Detectors, Pradeep Senanayake, Chung-Hong Hung, Alan C. Farrell, David A. Ramirez, Joshua Shapiro, Chi-Kang Li, Yuh-Renn Wu, Majeed M. Hayat, Diana L. Huffaker

Electrical and Computer Engineering Faculty Research and Publications

We demonstrate a nanopillar (NP) device structure for implementing plasmonically enhanced avalanche photodetector arrays with thin avalanche volumes (∼ 310 nm × 150 nm × 150 nm). A localized 3D electric field due to a core–shell PN junction in a NP acts as a multiplication region, while efficient light absorption takes place via surface plasmon polariton Bloch wave (SPP-BW) modes due to a self-aligned metal nanohole lattice. Avalanche gains of ∼216 at 730 nm at −12 V are obtained. We show through capacitance–voltage characterization, temperature-dependent breakdown measurements, and detailed device modeling that the avalanche region is on the order of …

Modeling Of Yeast Pheromone Pathway Using Petri Nets, Abhishek Majumdar

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Yeast (Saccharomyces cerevisiae) is one of the most widely studied single celled organisms. Mating of yeast cells occur between cells of opposite mating types a and alpha. Pheromone secretion by a cell alerts the corresponding opposite type cell about its presence and eventually facilitates the process of mating between them. The details of how pheromones affect cells can be studied from the pheromone response pathway in a yeast cell. A response pathway typically depicts the chain of interactions that happens between the different proteins in the cells in response to the pheromone. In this thesis we model the …

Pc-Based Automated Control System For Jordan Northern Grain Silo, Salem Al-Agtash

Computer Science and Engineering

This paper presents a PC-based automated control system operation of the Northern Grain Silo of Jordan. The system connects to a PLC (programmable logic controller) device, and combines operator interface, PLC programming and monitoring functions into one platform. The PLC portion handles direct operations control, while the PC portion handles interfacing and data intensive functions. A simulation package is developed. The package generates a graphical user interface for real-time graphic animations of the Grain Silo operation. We discuss anticipated benefits of such a system and phases of implementation.

Imitating Individualized Facial Expressions In A Human-Like Avatar Through A Hybrid Particle Swarm Optimization - Tabu Search Algorithm, Evan Husk

HIM 1990-2015

This thesis describes a machine learning method for automatically imitating a particular person's facial expressions in a human-like avatar through a hybrid Particle Swarm Optimization - Tabu Search algorithm. The muscular structures of the facial expressions are measured by Ekman and Friesen's Facial Action Coding System (FACS). Using a neutral face as a reference, the minute movements of the Action Units, used in FACS, are automatically tracked and mapped onto the avatar using a hybrid method. The hybrid algorithm is composed of Kennedy and Eberhart's Particle Swarm Optimization algorithm (PSO) and Glover's Tabu Search (TS). Distinguishable features portrayed on the …

A Unifying Approach To Behavioral Coverage, Elena Sherman

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Developing methods for validating that a program works as intended is one of the key research areas in software engineering. Ideally a program P must exhibit its expected be- havior, or property, φ on all of its inputs, i.e., P |= φ. The software engineering community has developed various program analysis approaches to assess whether P |= φ. In general, these approaches can be partitioned into dynamic and static program analysis. The former execute P on a particular input and checks that the execution conforms to φ. The latter in- terprets the code of P and check that on all …

Phoneme Weighting And Energy-Based Weighting For Speaker Recognition, Eric Fang

All Dissertations

This dissertation focuses on determining specific vowel phonemes which work best for speaker identification and speaker verification, and also developing new algorithms to improve speaker identification accuracy. Results from the first part of our research indicate that the vowels /i/, /E/ and /u/ were the ones having the highest recognition scores for both the Gaussian mixture model (GMM) and vector quantization (VQ) methods (at most one classification error). For VQ, /i/, /I/, /e/, /E/ and /@/ had no classification errors. Persons speaking /E/, /o/ and /u/ have been verified well by both GMM and VQ methods in our experiments. For …

Process Variation Aware Dram (Dynamic Random Access Memory) Design Using Block-Based Adaptive Body Biasing Algorithm, Satyajit Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Process variation can be defined as the deviation of process parameters from its nominal specifications. Variation is induced by several fundamental effects resulting from inaccuracies in the manufacturing equipment. It is a combination of systematic effects (e.g., lithographic lens aberrations) and random effects (e.g., dopant density fluctuations). The effect of process variation becomes particularly important at smaller process nodes, where the variation accounts for a major percentage of nominal length or width of the device. Process variations translate to a wide range in performance metrics of current designs. As technology scales, these die variations are getting larger, significantly affecting performance …

Connecting Architecture, Fitness, Optimizations And Performance Using An Anisotropic Diffusion Filter, Sumedh Naik

All Theses

Over the past decade, computing architectures have continued to exploit multiple levels of parallelism in applications. This increased interest in parallel computing has not only fueled the growth of multi-core processors but has also lead to an emergence of several non-traditional computing architectures like General Purpose Graphical Processing Units (GP-GPUs), Cell Processors, and Field Programmable Gate Arrays (FPGAs). Of these non-traditional computing architectures, GP-GPUs have gained widespread popularity due to their massively parallel computational abilities and relative ease of programmability.
Several software development ecosystems have emerged to harness the power of these parallel architectures. Although several threading libraries like POSIX …

Assessment Of Audio Interfaces For Use In Smartphone Based Spatial Learning Systems For The Blind, Shreyans Jain

Electronic Theses and Dissertations

Recent advancements in the field of indoor positioning and mobile computing promise development of smart phone based indoor navigation systems. Currently, the preliminary implementations of such systems only use visual interfaces—meaning that they are inaccessible to blind and low vision users. According to the World Health Organization, about 39 million people in the world are blind. This necessitates the need for development and evaluation of non-visual interfaces for indoor navigation systems that support safe and efficient spatial learning and navigation behavior. This thesis research has empirically evaluated several different approaches through which spatial information about the environment can be conveyed …

Post Processing Of Optically Recognized Text Using First Order Hidden Markov Model, Spandana Malreddy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis, we report on our design and implementation of a post processing system for Optically Recognized text. The system is based on first order Hidden Markov Model (HMM). The Maximum Likelihood algorithm is used to train the system with over 150 thousand characters. The system is also tested on a file containing 5688 characters. The percentage of errors detected and corrected is 11.76% with a recall of 10.16% and precision of 100%

Hardware-Software Co-Design, Acceleration And Prototyping Of Control Algorithms On Reconfigurable Platforms, Desta Kumsa Edosa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Differential equations play a significant role in many disciplines of science and engineering. Solving and implementing Ordinary Differential Equations (ODEs) and partial Differential Equations (PDEs) effectively are very essential as most complex dynamic systems are modeled based on these equations. High Performance Computing (HPC) methodologies are required to compute and implement complex and data intensive applications modeled by differential equations at higher speed. There are, however, some challenges and limitations in implementing dynamic system, modeled by non-linear ordinary differential equations, on digital hardware. Modeling an integrator involves data approximation which results in accuracy error if data values are not considered …

Towards Trustworthy, Efficient And Scalable Distributed Wireless Systems, Ze Li

All Dissertations

Advances in wireless technologies have enabled distributed mobile devices to connect with each other to form distributed wireless systems. Due to the absence of infrastructure, distributed wireless systems require node cooperation in multi-hop routing. However, the openness and decentralized nature of distributed wireless systems where each node labors under a resource constraint introduces three challenges: (1) cooperation incentives that effectively encourage nodes to offer services and thwart the intentions of selfish and malicious nodes, (2) cooperation incentives that are efficient to deploy, use and maintain, and (3) routing to efficiently deliver messages with less overhead and lower delay. While most …

Learning Visual Features For The Avatar Captcha Recognition Challenge, Mohammed Korayem, Abdallah A. Mohamed, David Crandall, Roman Yampolskiy

Faculty Scholarship

Captchas are frequently used on the modern world wide web to differentiate human users from automated bots by giving tests that are easy for humans to answer but difficult or impossible for algorithms. As artificial intelligence algorithms have improved, new types of Captchas have had to be developed. Recent work has proposed a new system called Avatar Captcha, in which a user is asked to distinguish between facial images of real humans and those of avatars generated by computer graphics. This novel system has been proposed on the assumption that this Captcha is very difficult for computers to break. In …

De-Embedding In High Speed Design, Don Degroot, David Dunham

Faculty Publications

No abstract provided.

Extending The Battery-Powered Operating Time Of A Wireless Environmental Monitoring System, Ross Matthew Butler

Boise State University Theses and Dissertations

Advances in low-power microelectronics and sensor technologies have enabled the creation of sophisticated environmental monitoring systems capable of operating on battery power. Independence from a power outlet connection opens up many new potential applications, but limited battery life still imposes significant restrictions on a monitoring system’s capabilities and the number of systems that can be economically deployed and maintained. These restrictions have motivated much research into reducing monitoring system energy usage, increasing battery capacity, and harnessing alternative energy sources. While most of the research focuses on new system design, there is a need for techniques to extend the battery-powered operating …

Validation Of Weak Form Thermal Analysis Algorithms Supporting Thermal Signature Generation, Elton Lewis Freeman

Masters Theses

Extremization of a weak form for the continuum energy conservation principle differential equation naturally implements fluid convection and radiation as flux Robin boundary conditions associated with unsteady heat transfer. Combining a spatial semi-discretization via finite element trial space basis functions with time-accurate integration generates a totally node-based algebraic statement for computing. Closure for gray body radiation is a newly derived node-based radiosity formulation generating piecewise discontinuous solutions, while that for natural-forced-mixed convection heat transfer is extracted from the literature. Algorithm performance, mathematically predicted by asymptotic convergence theory, is subsequently validated with data obtained in 24 hour diurnal field experiments for …

Mapping And Visualizing Ancient Water Storage Systems With An Rov – An Approach Based On Fusing Stationary Scans Within A Particle Filter, William D. Mcvicker

Master's Theses

This paper presents a new method for constructing 2D maps of enclosed un- derwater structures using an underwater robot equipped with only a 2D scanning sonar, compass and depth sensor. In particular, no motion model or odometry is used. To accomplish this, a two step offline SLAM method is applied to a set of stationary sonar scans. In the first step, the change in position of the robot between each consecutive pair of stationary sonar scans is estimated using a particle filter. This set of pair wise relative scan positions is used to create an estimate of each scan’s position …

Low Cost Neurochairs, Frankie Pike

Master's Theses

Electroencephalography (EEG) was formerly confined to clinical and research settings with the necessary hardware costing thousands of dollars. In the last five years a number of companies have produced simple electroencephalograms, priced below $300 and available direct to consumers. These have stirred the imaginations of enthusiasts and brought the prospects of "thought-controlled" devices ever closer to reality. While these new devices were largely targeted at video games and toys, active research on enabling people suffering from debilitating diseases to control wheelchairs was being pursued. A number of neurochairs have come to fruition offering a truly hands-free mobility solution, but whether …

Hardware Implementation Of Processor Allocator For Mesh Connected Chip Multiprocessors, Rana Sangram Reddy Marri

UNLV Theses, Dissertations, Professional Papers, and Capstones

The advancements in the semiconductor process technology and the current demand for highly parallel computing has led to the advent of Chip Multiprocessors (CMPs). CMP is the integration of two or more independent processor cores, which can read and execute program instructions, on to a single integrated circuit die. CMPs are the main computing platforms for research and development in parallel and high performance computing environments. They offer minimum inter-core communication latencies as the processor cores are present on a single chip.

The Operating System (OS) plays a key role in using a CMP effectively. The OS should support a …

Amaethon – A Web Application For Farm Management And An Assessment Of Its Utility, Tyler Yero

Master's Theses

Amaethon is a web application that is designed for enterprise farm management. It takes a job typically performed with spreadsheets, paper, or custom software and puts it on the web. Farm administration personnel may use it to schedule farm operations and manage their resources and equipment. A survey was con- ducted to assess Amaethon’s user interface design. Participants in the survey were two groups of students and a small group of agriculture professionals. Among other results, the survey indicated that a calendar interface inside Amaethon was preferred, and statistically no less effective, than a map interface. This is despite the …

Casting A Wider Net, Lynn Stein

Lynn Andrea Stein

This article is a book review of Mung Chiang's book Networked Life: 20 Questions and Answers. In this text intended for both classroom and online learning, Chiang uses questions about our online lives to explore the technology and computer science behind the Internet, wireless, and Web industries.

The Legal Challenges Of Networked Robotics: From The Safety Intelligence Perspective, Yueh-Hsuan Weng, Sophie T.H. Zhao

Yueh-Hsuan Weng

Mobile First Web And Content Strategy, Stefanie Havelka, David Stevens

Publications and Research

The paradigm shift from the traditional desktop to the mobile web experience is fast approaching, and providing relevant date, location and time-sensitive content to users via mobile devices becomes an essential piece of the overall web strategy. This presentation demonstrates the concepts, techniques and technologies used to develop both the overall mobile content strategy and user experience, as well as the aggregation and delivery of content to both the desktop and mobile form factors from a single content source.