Physical Sciences and Mathematics Commons^™

Hybrid Electric Vehicle Energy Management Strategy With Consideration Of Battery Aging, Bin Zhou

Dissertations, Master's Theses and Master's Reports

The equivalent consumption minimization strategy (ECMS) is a well-known energy management strategy for Hybrid Electric Vehicles (HEV). ECMS is very computationally efficient since it yields an instantaneous optimal control. ECMS has been shown to minimize fuel consumption under certain conditions. But, minimizing the fuel consumption often leads to excessive battery damage. The objective of this dissertation is to develop a real-time implementable optimal energy management strategy which improves both the fuel economy and battery aging for Hybrid Electric Vehicles by using ECMS. This work introduces a new optimal control problem where the cost function includes terms for both fuel consumption …

Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano

Dissertations, Master's Theses and Master's Reports

The study was focused on the Anak Krakatau sector collapse that occurred on 22 December 2018 in the Sunda Strait (Indonesia). The goal of the study was to monitor and analyze changes of the volcanic edifice and to try to understand causes that may have predisposed and triggered the sector collapse.

The use of different remote sensing techniques allowed the acquisition of thermal data, SO₂ emission data, structural data and the identification and analysis of the eruptive events that occurred on Anak Krakatau in the period from 1° January 2016 to 28 February 2019. The acquisition of 1221 thermal …

The Singular Value Expansion For Compact And Non-Compact Operators, Daniel Crane

Dissertations, Master's Theses and Master's Reports

Given any bounded linear operator T : X → Y between separable Hilbert spaces X and Y , there exists a measure space (M, Α, µ) and isometries V : L²(M) → X, U : L²(M) → Y and a nonnegative, bounded, measurable function σ : M → [0, ∞) such that

T = Um_σV ^†,

with m_σ : L²(M ) → L²(M ) defined by m_σ(f ) = σf for all f …

Cosmic-Ray Acceleration In The Cygnus Ob2 Stellar Association, Binita Hona

Dissertations, Master's Theses and Master's Reports

The Cygnus region of our Galaxy consists of an active star forming region and a wealth of various astrophysical sources such as pulsar wind nebulae (PWN), supernova remnants (SNRs), and massive star clusters. Massive stellar clusters and associations have been postulated as possible sources of cosmic rays (CRs) in our Galaxy. One example of a gamma-ray source associated with a stellar association lies in the Cygnus region known as the "Cygnus Cocoon". It is an extended region of gamma-ray emission in the Cygnus X region and attributed to a possible superbubble with freshly accelerated CRs which are hypothesized to produce …

Understanding The Mechanisms Controlling The Concentration-Discharge Relationships Of Streams In Northeastern And North Midwestern United States, Veronica Porter

Dissertations, Master's Theses and Master's Reports

Analysis of concentration-discharge (C-Q) power-law relationships (C=aQ^b) is a powerful diagnostic tool to unravel solute export processes. However, application to watersheds with less intensive data can be difficult due to unexplained variation in C-Q behavior. To tackle this problem, I started my study at a small but data-intensive watershed in Vermont and then applied the insights to 138 watersheds throughout the Great Lakes Basin (GLB). I found that an increase in solute concentrations from shallow to deep flowpaths results in chemodynamic dilution (negative b-coefficient), a decrease produces chemodynamic flushing (positive b-coefficient). When applied …

Magnetism In Γ-Fesi2 Nanostructures: A First Principles Study, Sahil Dhoka

Dissertations, Master's Theses and Master's Reports

First-principles calculations are performed on γ-FeSi₂ nanostructures grown on Si (111) and (001) substrate. An attempt to explain the origin of emergent magnetic properties of the metastable gamma phase of iron di-silicide (γ-FeSi₂) is made, which show ferromagnetic behavior on nanoscale, unlike its possible bulk form. Many papers try to explain this magnetism from factors like bulk, epitaxial strain, interface, surface, edges, and corners but doesn’t provide an analytical study for these explanations. Density functional theory is used to analyze the magnetic effects of these factors. The results for the epitaxial structures show no magnetic behavior for …

Modeling The Effects Of Hydrologic Service Payments On The Hydrology Of Tropical Montane Watersheds In Central Veracruz, Mexico., Sergio Miguel López Ramírez

Dissertations, Master's Theses and Master's Reports

An analysis of the effects of the Land Use Land Cover (LULC) change and its impacts on the hydrological cycle of tropical montane catchments influenced by cloud forest (TMCF) is developed in Central Veracruz, Mexico. This work started with the analysis of data from monitored-micro-catchments with contrasting LULC. Later the suitability of an improved version of the Soil and Water Assessment Tool model for the Tropics (SWAT-T) was evaluated. Finally, potential future land use scenarios, including conservation targeting alternatives were evaluated using a calibrated Seasonal Water Yield model as part of the Integrated Valuation of Ecosystem Services and Tradeoffs framework …

The Impacts Of Accessibility On Vulnerability Of Place In Comfort Castle, Jamaica, Heather Thole

Dissertations, Master's Theses and Master's Reports

Jamaica experiences meteorological, hydrological, and geological natural hazards that can produce island-wide impacts. The island’s exposure to multiple hazard types requires effective and sustainable mitigation and disaster risk management to lessen potential impacts, especially for vulnerable populations and communities. Comfort Castle, a small rural farming community, sits in the upper Rio Grande Valley of Portland parish and experiences earthquakes, landslides, hurricanes, heavy rainfall, and floods. Steep terrain and remoteness due to geographic location affect the community’s geophysical vulnerability. Their social vulnerability results from a lack of employment, health, educational, and livelihood resources within the community. Together, geophysical, and social factors …

Rain Generated Lahars Prior To The 2018 Catastrophic Eruption Of Fuego Volcano, Guatemala, Claudia Buondonno

Dissertations, Master's Theses and Master's Reports

Fuego volcano is one of the most active and hazardous volcanoes in the world. It is located in the northern part of the Central American Volcanic Arc in Guatemala and its activity can be characterized by long term, low-level background activity, and sporadic larger explosive eruptions. Its historical observations of eruptions date back to 1531, but it has been erupting vigorously since 2002 with major activity throughout 2018, producing three main eruptions in February, June and November. Its almost persistent activity generates major ashfalls, pyroclastic flows, lava flows; when heavy rains mobilize its deposits, they can form damaging lahars. Phenomena, …

Uniform Three-Class Regular Partial Steiner Triple Systems With Uniform Degrees, Prangya Rani Parida

Dissertations, Master's Theses and Master's Reports

A Partial Steiner Triple system (X, T) is a finite set of points C and a collection T of 3-element subsets of C that every pair of points intersect in at most 1 triple. A 3-class regular PSTS (3-PSTS) is a PSTS where the points can be partitioned into 3 classes (each class having size m, n and p respectively) such that no triple belongs to any class and any two points from the same class occur in the same number of triples (a, b and c respectively). The 3-PSTS is said to be uniform if m = n = …

Quantifying Water Recharge And Water Use In Hand Dug Wells: A Case Study Of Thiawor, Senegal, West Africa, Celine Carus

Dissertations, Master's Theses and Master's Reports

For many rural communities in Senegal, water is an essential life-giving need received only through a network of hand dug wells. Increasing rainfall variability in the Sahel has driven greater water insecurity for those communities that rely on rain-irrigated systems for agriculture. This study investigates the retrieval, purposes, and quantities of seasonal water usage on a small domestic scale, as well as an analysis of perceived water availability in the wells during the rainy season. Additionally, using a combination of interview data and pumping test data obtained from the village wells, water usage and estimated daily needs are calculated and …

Higher Accuracy Methods For Fluid Flows In Various Applications: Theory And Implementation, Dilek Erkmen

Dissertations, Master's Theses and Master's Reports

This dissertation contains research on several topics related to Defect-deferred correction (DDC) method applying to CFD problems. First, we want to improve the error due to temporal discretization for the problem of two convection dominated convection-diffusion problems, coupled across a joint interface. This serves as a step towards investigating an atmosphere-ocean coupling problem with the interface condition that allows for the exchange of energies between the domains.

The main diffuculty is to decouple the problem in an unconditionally stable way for using legacy code for subdomains. To overcome the issue, we apply the Deferred Correction (DC) method. The DC method …

Optical Dispersion Relations From Three-Dimensional Chiral Gold Nanocubes In Periodic Arrays, Manpreet Boora

Dissertations, Master's Theses and Master's Reports

Chiral metamaterials are artificially tailored materials that are composed of nanoparticles that lack in-plane mirror symmetry. Application of chirality to plasmonic nanostructures can lead to chiro-optical effects such as asymmetric transmission of circularly polarized light, circular dichroism and optical activity. When light is incident on metallic nanoparticles, conduction electrons undergo collective oscillations within the nanoparticles, resulting in localized surface plasmon (LSP) resonance. Surface lattice resonances (SLRs) are hybrid plasmonic-photonic modes arising from the radiative coupling between LSPs and electromagnetic waves diffracted in the plane of the periodic array. Because of the collective dipole interactions, SLRs have less radiative losses compared …

The Effect Of Spacing Of Vetiver Grass (Chrysopogon Zizanioides) Hedgerows On Hillslope Erosion In Eastern Region, Ghana, Evan R. Lanese

Dissertations, Master's Theses and Master's Reports

Soil erosion in Ghana negatively effects many small holder farmers due to heavy rainfall, continuous land use, and a changing climate. Inexpensive, local, and sustainable practices that can be used to reduce soil movement thus building productive soils would benefit farmers in Ghana. Vetiver grass (Chrysopogon zizanioides) has been used to this effect worldwide. Its local availability and positive reputation leaves desire to learn about its applicability in Ghana. A field study was conducted on plots of sloping farmland (10ft by 60ft) with three treatments: (1) control with no vetiver grass, (2) two vetiver grass hedgerows, (3) four …

Matlabta: A Style Critiquer For Novice Engineering Students, Marissa L. Walther

Dissertations, Master's Theses and Master's Reports

Novice programmers, considered to be those who have yet to understand the fundamentals of programming, exist in both engineering and computing fields. Within computing, various resources exist to help novice programmers understand fundamentals and style guidelines such as WebTA, a code critique program that gives Java students feedback about their error and style issues. There is, however, a gap in automated code critique for MATLAB, a programming language that is popular in the engineering community. When it comes to MATLAB, there are not many programs that help novices understand their errors, and even fewer that help them understand style guidelines. …

Demand-Driven Execution Using Future Gated Single Assignment Form, Omkar Javeri

Dissertations, Master's Theses and Master's Reports

This dissertation discusses a novel, previously unexplored execution model called Demand-Driven Execution (DDE), which executes programs starting from the outputs of the program, progressing towards the inputs of the program. This approach is significantly different from prior demand-driven reduction machines as it can execute a program written in an imperative language using the demand-driven paradigm while extracting both instruction and data level parallelism. The execution model relies on an executable Single Assignment Form which serves both as the internal representation of the compiler as well as the Instruction Set Architecture (ISA) of the machine. This work develops the instruction set …

Ratiometric Near-Infrared Fluorescent Probes For The Sensitive Detection Of Intracellular Ph And Bio-Thiols In Live Cells, Shuai Xia

Dissertations, Master's Theses and Master's Reports

In the past twenty years, fluorescence sensing and imaging based on fluorescent probes has been developed as an imperative technique due to the merits including excellent sensitivity, operational simplicity, instant time effectiveness and outstanding selectivity in the research areas such as mineralogy, gemology, biological medicine, materials and environmental engineering. Protons act as a significant role in a variety of pathological and physiological processes, and there are obvious differences in the pH among organelles: the pH in lysosomes is acid within the range of 4.5–5.5, whereas mitochondrial pH is basic that can be as high as 8.0. Abnormal intracellular pH is …

Critiquing Antipatterns In Novice Code, Leo C. Ureel Ii

Dissertations, Master's Theses and Master's Reports

Students in introductory computer science courses, are learning to program. Indeed, most students perceive that learning to code is the central topic explored in the courses. Students spend an enormous amount of time struggling to learn the syntax and understand semantics of a particular language. Instructors spend a similar amount of time reading student code and explaining the meaning of the cryptic error messages displayed by compilers. Messages provided by compilers are intended to give feedback on the adherence of one’s code to the language specification and conventions. Unfortunately, these message are geared towards experts who have a clear understanding …

Dissolved Organic Matter Movement Across Lake Superior’S Terrestrial-Stream-Coastal Interface, Karl M. Meingast

Dissertations, Master's Theses and Master's Reports

Dissolved organic matter (DOM) represents a carbon pool that can be easily translocated between ecosystems with the movement of water. This study examines the controls on DOM quantity and character delivered to Lake Superior primarily during the snowmelt period. We employed long-term stream dissolved organic carbon (DOC) data to determine quantity as well as absorption and fluorescence spectroscopy to analyze DOM structure. Our results indicate that an increasing trend in DOC concentrations, likely driven by decreases in acidity of precipitation, combined with slightly less annual runoff have resulted in relatively constant fluxes of DOM to Lake Superior. Additionally, our study …

The Stained Glass Of Knowledge: On Understanding Novice Mental Models Of Computing, Briana Christina Bettin

Dissertations, Master's Theses and Master's Reports

Learning to program can be a novel experience. The rigidity of programming can be at odds with beginning programmer's existing perceptions, and the concepts can feel entirely unfamiliar. These observations motivated this research, which explores two major questions: What factors influence how novices learn programming? and How can analogy by more appropriately leveraged in programming education?

This dissertation investigates the factors influencing novice programming through multiple methods. The CS1 classroom is observed as a "whole system", with consideration to the factors present in it that can influence the learning process. Learning's cognitive processes are elaborated to ground exploration into specifically …

Assessing The Accuracy Of A Uav Snow Depth Survey: Utqiagvik (Barrow), Alaska Calm Grid, Ian Nichols

Dissertations, Master's Theses and Master's Reports

Active layer depth and snow depth are annually collected across the Circumpolar Active Layer Monitoring (CALM) Network to observe the response of the active layer and near-surface permafrost to climate change over decadal-time scales. Snow depth is typically measured using a graduated steel probe at each grid node but, in this paper, we explore the viability of using Unmanned Aerial Vehicle (UAV) (drone) technology to collect snow depth measurements at the 1 km² Utqiagvik (Barrow), Alaska CALM grid. This is achieved by comparing estimated UAV snow depths to measured snow depths collected using a MagnaProbe (MP) at each of …

Stochastic Inversion Integrating Seismic Data, Litho-Facies Physical Properties, And Multiple-Point Geostatistics For Reservoir Characterization, Mohamed Mohamed

Dissertations, Master's Theses and Master's Reports

We proposed a novel seismic inversion approach that integrates the physical properties of litho-facies, and geophysical data, within the multiple-point geostatistical frameworks to reduce the uncertainty in predictions of litho-facies spatial arrangement away from wells or control points. The litho-facies groups (rock-type) in the well locations are defined and conditioned to the distribution of elastic properties, including P-wave velocity (Vp) and facies density (ρ) in the well locations. A conceptual geological model (training image) is utilized within a wavelet-based multiple-point geostatistical simulation (WAVESIM) algorithm to generate litho-facies realizations. In our inversion algorithm, the forward model is created by implementing the …

Joint Simulation Of Continuous And Categorical Variables For Mineral Resource Modeling And Recoverable Reserves Calculation, Sentle Augustinus Hlajoane

Dissertations, Master's Theses and Master's Reports

Spatial variability and uncertainty of continuous variables (grade) and categorical variables (rock-types) in mineral evaluation significantly impact the economics of mining projects. The conventional approach of simulating grades using deterministic rock- types is problematic since spatial variability, and uncertainty of grades at rock-type contacts are not well captured in deposits where the grade changes gradually between rock-types. Therefore, jointly simulating these variables can improve confidence (reduce uncertainty) in a resource model. Also, resource classification and recoverable reserve calculation can significantly improve the understanding of the deposit and its economic viability. This research utilized the Plural-Gaussian geostatistical simulation to jointly simulate …

Sub-Sampled Matrix Approximations, Joy Azzam

Dissertations, Master's Theses and Master's Reports

Matrix approximations are widely used to accelerate many numerical algorithms. Current methods sample row (or column) spaces to reduce their computational footprint and approximate a matrix A with an appropriate embedding of the data sampled. This work introduces a novel family of randomized iterative algorithms which use significantly less data per iteration than current methods by sampling input and output spaces simultaneously. The data footprint of the algorithms can be tuned (independent of the underlying matrix dimension) to available hardware. Proof is given for the convergence of the algorithms, which are referred to as sub-sampled, in terms of numerically tested …

Fluid Inclusion Study Of Selected Calcite Associated With Native Copper, Quincy Mine, Keweenaw Peninsula, Michigan, David Kelly

Dissertations, Master's Theses and Master's Reports

The Keweenaw Peninsula is famous for hosting the largest accumulation of native copper anywhere in the world. Previous studies have looked for the fluids responsible for creating the native copper deposits but were unable to conclusively demonstrate that fluid inclusions can provide valuable insight into the hydrothermal/metamorphogenic fluids responsible for these unique deposits.

This report focused on fluid inclusions from calcite precipitated during the native copper mineralizing event. Calcite crystals with inclusions of native copper growing into vugs from a single location, the Quincy Mine, were hypothesized to have a higher chance to be undisturbed by seismic events that would …

Exploring Substrate Specificity Of Fructose Transporters En Route To Glut Specific Probes For Biochemical And Biomedical Applications, Vagarshak Vigenovich Begoyan

Dissertations, Master's Theses and Master's Reports

Carbohydrate Transporters (GLUTs) are responsible for the transportation of sugars into the cell and have been of great interest in research for decades. Alterations or mutations that result in overexpression of GLUTs have been linked to a great number of diseases including, obesity, diabetes, and cancer. Differentiation between transporters has been shown to be incredibly difficult due to the highly conserved nature of the transporter structure, and thus specific targeting of transporters has proven a difficult challenge. Additionally, the GLUTs have been shown to high flexibility in their conformations, so it is difficult to determine what can or cannot pass …

Physical Modeling Of The Krauklis Waves: Insights From Two Experimental Apparatuses, Haitao Cao

Dissertations, Master's Theses and Master's Reports

Fractures play an important role in the geological related processes such as hydraulic fracturing, water-water disposal, and volcanic earthquake. Seismic waves can provide useful information from fractures at a relatively low cost. In particular, the acoustic property of fractures containing magmatic or hydrothermal fluids can provide useful information about the fracture size and the fluid composition within the fracture. For instance, in volcanology, the resonant frequency of long-period events that are linked to crack interface waves is used to obtain fluid properties of cracks in magmatic systems. However, in order to rely on seismic data, they should be precisely characterized …

A Multi-Year Analysis From 2014 To 2017 Of Snowfall Types In Marquette, Michigan: A Differentiation Between Synoptic Snow Events And Lake Effect Snow Events Impacted By The Presence Of Lake Superior, Roberto Piemontese

Dissertations, Master's Theses and Master's Reports

The present study analyzes four winter seasons of data from 2014 to 2017 collected from the National Weather Service in Marquette, Michigan. The two main instruments installed are the MRR, which provides a vertical reflectivity profile from ground level to 3 km, and the PIP, a horizontal camera pointing towards a light source, which measures the physical characteristics of each particle. The observations show that LES events are shallow, with heights of up to 1500 m, meanwhile synoptic events are deep, with vertical profile of 3000 m or beyond. The shallow events have bigger and low-density particles and synoptic events …