Computer Engineering Commons^™

Improving The Resilience Of Cyber-Physical Systems Under Strategic Adversaries, Paul Wood

Open Access Dissertations

Renewable energy resources challenge traditional energy system operations by substituting the stability and predictability of fossil fuel based generation with the unreliability and uncertainty of wind and solar power. Rising demand for green energy drives grid operators to integrate sensors, smart meters, and distributed control to compensate for this uncertainty and improve the operational efficiency of the grid. Real-time negotiations enable producers and consumers to adjust power loads during shortage periods, such as an unexpected outage or weather event, and to adapt to time-varying energy needs. While such systems improve grid performance, practical implementation challenges can derail the operation of …

Exploring Dynamic Memory Allocations For Bioinformatics Applications, Nitya Kovur

School of Computing: Dissertations, Theses, and Student Research

The progression of scientific data leads to an increase in the demand of powerful high performance computers (HPC) where data can be stored and analyzed. High performance computing is used in several research areas to solve large problems. However, efficient usage of supercomputing resources that are available is a major concern for most of the researchers. The user has to choose the amount of resources needed for execution before submitting the job. Over or under subscription of resources leads to low system utilization and/or low user satisfaction.

Bioinformatics is one such field that heavily relies on HPC. One of the …

Activity Analysis Of Spectator Performer Videos Using Motion Trajectories, Anish Timsina

School of Computing: Dissertations, Theses, and Student Research

Spectator Performer Space (SPS) is a frequently occurring crowd dynamics, composed of one or more central performers, and a peripheral crowd of spectators. Analysis of videos in this space is often complicated due to occlusion and high density of people. Although there are many video analysis approaches, they are targeted for individual actors or low-density crowd and hence are not suitable for SPS videos. In this work, we present two trajectory-based features: Histogram of Trajectories (HoT) and Histogram of Trajectory Clusters (HoTC) to analyze SPS videos. HoT is calculated from the distribution of length and orientation of motion trajectories in …

Eventflowslicer: A Goal-Based Test Case Generation Strategy For Graphical User Interfaces, Jonathan Saddler

School of Computing: Dissertations, Theses, and Student Research

Automated test generation techniques for graphical user interfaces include model-based approaches that generate tests from a graph or state machine model of the interface, capture-replay methods that require the user to specify and demonstrate each test case individually, and modeling-language approaches that provide templates for abstract test cases. There has been little work, however, in automated goal-based testing, where the goal is a realistic user task, a function, or an abstract behavior. Recent work in human performance regression testing (HPRT) has shown that there is a need for generating multiple test cases that execute the same user task in different …

Asynchronous Data Processing Platforms For Energy Efficiency, Performance, And Scalability, Liang Men

Graduate Theses and Dissertations

The global technology revolution is changing the integrated circuit industry from the one driven by performance to the one driven by energy, scalability and more-balanced design goals. Without clock-related issues, asynchronous circuits enable further design tradeoffs and in operation adaptive adjustments for energy efficiency. This dissertation work presents the design methodology of the asynchronous circuit using NULL Convention Logic (NCL) and multi-threshold CMOS techniques for energy efficiency and throughput optimization in digital signal processing circuits. Parallel homogeneous and heterogeneous platforms implementing adaptive dynamic voltage scaling (DVS) based on the observation of system fullness and workload prediction are developed for balanced …

A System For Monitoring And Managing Indoor Air Quality And Environmental Conditions, Ali Ibrahim

Boise State University Theses and Dissertations

The quality of indoor air depends on different types of pollutant sources existing in a semi-enclosed environment. The sources can be biological, chemical, or toxic pollutants. These sources can cause health issues and discomfort for occupants. One of the indicators of poor indoor air quality is Carbon Dioxide (CO₂). CO₂ can be used to indicate the indoor air exchange rate. The lack of air exchange means higher levels of CO₂. High levels of indoor particulates can also be an indication of poor air quality. Due to the lack of fresh air, air circulation, and air …

Inducing Emotional Response In Interactive Media, Keenan M. Reimer

Master's Theses

Video games, and entertainment media have been developed for many years, and eliciting emotional experiences is an integral part of that process. Producing and editing game content in order to affect desired emotional experiences can be expensive and cumbersome to developers. This paper presents a study intended to show that such experiences can be affected with simple after-the-fact audio-visual effects. As subjects of the study, participants experience three different emotional states, fear, peace, and none, over three rounds and in three different game environments. They are given a simple narrative in each environment that directs them to gather various objects. …

Multi-Sensory Emotion Recognition With Speech And Facial Expression, Qingmei Yao

Dissertations

Emotion plays an important role in human beings’ daily lives. Understanding emotions and recognizing how to react to others’ feelings are fundamental to engaging in successful social interactions. Currently, emotion recognition is not only significant in human beings’ daily lives, but also a hot topic in academic research, as new techniques such as emotion recognition from speech context inspires us as to how emotions are related to the content we are uttering.

The demand and importance of emotion recognition have highly increased in many applications in recent years, such as video games, human computer interaction, cognitive computing, and affective computing. …

Cufa: A More Formal Definition For Digital Forensic Artifacts, Vikram S. Harichandran, Daniel Walnycky, Ibrahim Baggili, Frank Breitinger

Electrical & Computer Engineering and Computer Science Faculty Publications

The term “artifact” currently does not have a formal definition within the domain of cyber/ digital forensics, resulting in a lack of standardized reporting, linguistic understanding between professionals, and efficiency. In this paper we propose a new definition based on a survey we conducted, literature usage, prior definitions of the word itself, and similarities with archival science. This definition includes required fields that all artifacts must have and encompasses the notion of curation. Thus, we propose using a new term e curated forensic artifact (CuFA) e to address items which have been cleared for entry into a CuFA database (one …

Deleting Collected Digital Evidence By Exploiting A Widely Adopted Hardware Write Blocker, Christopher S. Meffert, Ibrahim Baggili, Frank Breitinger

Electrical & Computer Engineering and Computer Science Faculty Publications

In this primary work we call for the importance of integrating security testing into the process of testing digital forensic tools. We postulate that digital forensic tools are increasing in features (such as network imaging), becoming networkable, and are being proposed as forensic cloud services. This raises the need for testing the security of these tools, especially since digital evidence integrity is of paramount importance. At the time of conducting this work, little to no published anti-forensic research had focused on attacks against the forensic tools/process.We used the TD3, a popular, validated, touch screen disk duplicator and hardware write blocker …

Design And Implementation Of Benes/Clos On-Chip Interconnection Networks, Yikun Jiang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Networks-on-Chip (NoCs) have emerged as the key on-chip communication architecture for multiprocessor systems-on-chip and chip multiprocessors. Single-hop non-blocking networks have the advantage of providing uniform latency and throughput, which is important for cachecoherent NoC systems. Existing work shows that Benes networks have much lower transistor count and smaller circuit area but longer delay than crossbars. To reduce the delay, we propose to design the Clos network built with larger size switches. Using less than half number of stages than the Benes network, the Clos network with 4x4 switches can significantly reduce the delay. This dissertation focuses on designing high performance …

Design, Fabrication And Testing Of Monolithic Low-Power Passive Sigma-Delta Analog-To-Digital Converters, Angsuman Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Analog-to-digital converters are critically important in electronic systems. The

difficulty in meeting high performance parameters increases as integrated circuit design

process technologies advance into the deep nanometer region. Sigma-delta analog-todigital

converters are an attractive option to fulfill many data converter requirements.

These data converters offer high performance while relaxing requirements on the precision

of components within an integrated circuit. Despite this, the active integrators found within

sigma-delta analog-to-digital converters present two main challenges. These challenges are

the power consumption of the active amplifier and achieving gain-bandwidth necessary for

sigma-delta data converters in deep nanometer process technologies. Both of these

challenges …

Optimizing Virtual Resource Management In Cloud Datacenters, Liuhua Chen

All Dissertations

Datacenter clouds (e.g., Microsoft's Azure, Google's App Engine, and Amazon's EC2) are emerging as a popular infrastructure for computing and storage due to their high scalability and elasticity. More and more companies and organizations shift their services (e.g., online social networks, Dropbox file hosting) to clouds to avoid large capital expenditures. Cloud systems employ virtualization technology to provide resources in physical machines (PMs) in the form of virtual machines (VMs). Users create VMs deployed on the cloud and each VM consumes resources (e.g., CPU, memory and bandwidth) from its host PM. Cloud providers supply services by signing Service Level Agreement …

Learning In The Real World: Constraints On Cost, Space, And Privacy, Matt J. Kusner

McKelvey School of Engineering Graduate Student Theses & Dissertations

The sheer demand for machine learning in fields as varied as: healthcare, web-search ranking, factory automation, collision prediction, spam filtering, and many others, frequently outpaces the intended use-case of machine learning models. In fact, a growing number of companies hire machine learning researchers to rectify this very problem: to tailor and/or design new state-of-the-art models to the setting at hand.

However, we can generalize a large set of the machine learning problems encountered in practical settings into three categories: cost, space, and privacy. The first category (cost) considers problems that need to balance the accuracy of a machine learning model …

A Multilingual Semi-Supervised Approach In Deriving Singlish Sentic Patterns For Polarity Detection, Siaw Ling Lo, Erik Cambria, Raymond Chiong, David Cornforth

Research Collection School Of Computing and Information Systems

Due to the huge volume and linguistic variation of data shared online, accurate detection of the sentiment of a message (polarity detection) can no longer rely on human assessors or through simple lexicon keyword matching. This paper presents a semi-supervised approach in constructing essential toolkits for analysing the polarity of a localised scarce-resource language, Singlish (Singaporean English). Corpus-based bootstrapping using a multilingual, multifaceted lexicon was applied to construct an annotated testing dataset, while unsupervised methods such as lexicon polarity detection, frequent item extraction through association rules and latent semantic analysis were used to identify the polarity of Singlish n-grams before …

Improving The Efficiency Of Ci With Uber-Commits, Matias Waterloo

School of Computing: Dissertations, Theses, and Student Research

Continuous Integration (CI) is a software engineering practice where developers break their coding tasks into small changes that can be integrated with the shared code repository on a frequent basis. The primary objectives of CI are to avoid integration problems caused by large change sets and to provide prompt developer feedback so that if a problem is detected, it can be easily and quickly resolved. In this thesis, we argue that while keeping changes small and integrating often is a wise approach for developers, the CI server may be more efficient operating on a different scale. In our approach, the …

Variable Response Of A Thermally Tuned Mems Pressure Sensor, Robert A. Lake, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

A typical microelectromechanical systems (MEMS) pressure sensor consists of a thin, deformable membrane and sensing element such as a piezoresistive element which is used to measure the amount of deflection in response to an applied pressure. Previous efforts demonstrated that buckled membranes, from silicon on insulator (SOI) wafers, can be thermally tuned via joule heating. By applying heat to the membrane through a resistive heating element, compressive stress is induced in the membrane causing it to buckle further out of plane and increasing its overall stiffness response. It is demonstrated that by increasing the stiffness of the membrane, the response …

Use Of Clustering Techniques For Protein Domain Analysis, Eric Rodene

School of Computing: Dissertations, Theses, and Student Research

Next-generation sequencing has allowed many new protein sequences to be identified. However, this expansion of sequence data limits the ability to determine the structure and function of most of these newly-identified proteins. Inferring the function and relationships between proteins is possible with traditional alignment-based phylogeny. However, this requires at least one shared subsequence. Without such a subsequence, no meaningful alignments between the protein sequences are possible. The entire protein set (or proteome) of an organism contains many unrelated proteins. At this level, the necessary similarity does not occur. Therefore, an alternative method of understanding relationships within diverse sets of proteins …

Design Of Ferroelectric Mems Energy Harvesting Devices, Noah T. Blach, Robert A. Lake, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Waste heat is a widely available but little used source of power. Converting a thermal gradient into electricity is conventionally done using the Seebeck effect, but devices that use this effect are naturally inefficient. An alternate approach uses microelectromechanical systems (MEMS) to generate movement and time-varying temperature from a constant temperature gradient. Ferroelectric materials can harvest electricity from moving structures and temperature variations. This concept was realized using traditional silicon microprocessing techniques. A silicon on insulator (SOI) wafer was backside Deep Reactive Ion Etched (DRIE) to form a one mm² by 7 micron thick silicon/silicon dioxide membrane. Lead zirconate …

Engineered Surfaces To Control Secondary Electron Emission For Multipactor Suppression, James M. Sattler, Ronald A. Coutu Jr., Robert A. Lake, Tod V. Laurvick

Electrical and Computer Engineering Faculty Research and Publications

A significant problem for space-based systems is multipactor - an avalanche of electrons caused by repeated secondary electron emission (SEE). The consequences of multipactor range from altering the operation of radio frequency (RF) devices to permanent device damage. Existing efforts to suppress multipactor rely heavily on limiting power levels below a multipactor threshold [1]. This research applies surface micromachining techniques to create porous surfaces to control the secondary electron yield (SEY) of a material for multipactor suppression. Surface characteristics of interest include pore aspect ratio and density. A discussion is provided on the advantage of using electroplating (vice etching) to …