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State Of R In Hydrological Modelling, J. A. Torres, E. Pebesma Dec 2016

State Of R In Hydrological Modelling, J. A. Torres, E. Pebesma

Open Water Journal

Access to clean and safe water is a human right and to grant it under a sustainable development point of view is paramount for well being of the future generations. Therefore, it is important to understand the interaction between the mate- rial flows to coastal waters that are constrained by catchment boundaries and the human activi- ties therein, and those materials that are tied to trade and other trans-boundary processes (e.g. re- sidence time, transport and fate of physical, chemi- cal and microbiological water-quality determinants) and their global implications on preserving the qua- lity of the natural environment.


Cmf - An Open Source Hydrological Modelling Toolkit, Philipp Kraft, Hans-Georg Frede, Lutz Breuer Dec 2016

Cmf - An Open Source Hydrological Modelling Toolkit, Philipp Kraft, Hans-Georg Frede, Lutz Breuer

Open Water Journal

In the past four decades, hundreds (if not thousands) of hydrological models have been developed to predict the transfer of water through landscapes. Despite this variety of models, the basic challenge for all kind of models is the same: solve the dynamic local to global water mass balance of a landscape. However, the transport processes, surface flow, subsurface flow, snow drift, evaporation and transpiration can be modelled with differing complexity, theory and parameterizations. Clark et al. (2011) denote, that a hydrological model is therefore not one hypothesis of process behaviour, but a multitude of interconnected hypotheses, which remain untested, since …


Using The Finite Volume Method For Generalized Approach Of Catchment Models, Ina Plesca, Philipp Kraft, Hans-Georg Frede, Lutz Breuer Dec 2016

Using The Finite Volume Method For Generalized Approach Of Catchment Models, Ina Plesca, Philipp Kraft, Hans-Georg Frede, Lutz Breuer

Open Water Journal

Classical mathematical models and methods have been constantly applied to solve different hydrological problems, especially for water flux processes description. The Catchment Modeling Framework (CMF) is an open source, modular and expandable platform which has been created to simulate the water balance from plot to landscape scale. CMF consists of several modules, each applied for specific flux-processes depending on different parameters or dimensions. The CMF expandability allows applying hydrological model structures that fit best the current context.


Discontinuous Finite Element Mechanistic Water Quality Model For The Simulation Of Adsorptive Pollutants Transport In River Systems., F. P. Fiengo, L. Sweeck, M. Elskens, W. Bauwens Dec 2016

Discontinuous Finite Element Mechanistic Water Quality Model For The Simulation Of Adsorptive Pollutants Transport In River Systems., F. P. Fiengo, L. Sweeck, M. Elskens, W. Bauwens

Open Water Journal

The close interaction between humans, animals and the river system requires to have control about the concentration of different pollutants in the water column in order to avoid damage to the environment. Due to the fact that the measurements are time consuming, expensive and in most of the cases very local, it is required to develop tools in order to predict the spatial and temporal distribution of the pollutants in the system.

Once pollutant effluents are discharged in waters, part of them is transported in liquid phase and the rest is attached to the suspended sediments and to the bed …


Python Package For Model Structure Analysis (Pystan), S. Van Hoey, Johannes Van Der Kwast, I Nopens, P. Seuntjens Dec 2016

Python Package For Model Structure Analysis (Pystan), S. Van Hoey, Johannes Van Der Kwast, I Nopens, P. Seuntjens

Open Water Journal

The selection and identification of a suitable hydrological model structure is more than fitting parameters of a model structure to reproduce a measured hydrograph. The procedure is highly dependent on various criteria, i.e. the modelling objective, the characteristics and the scale of the system under investigation as well as the available data. Rigorous analysis of the candidate model structures is needed to support and objectify the selection of the most appropriate structure for a specific case (or eventually justify the use of a proposed ensemble of structures). This holds both in the situation of choosing between a limited set of …


Influence Of Seasonality On Salmonella Concentration And Dynamics In Khartoum Wastewater Stabilization Station, Ayman A. Elshayeb, Abdelazim A. Ahmed, Adil A. El-Hussien Dec 2016

Influence Of Seasonality On Salmonella Concentration And Dynamics In Khartoum Wastewater Stabilization Station, Ayman A. Elshayeb, Abdelazim A. Ahmed, Adil A. El-Hussien

Open Water Journal

Introduction: Seasonal weather variables are universal and can obviously affect different Salmonella sp populations’ dynamics in wastewater influencing their fluctuations.

Objectives: This work was conducted to create a predictive mathematical model for Salmonella spread, distribution and outbreak in local wastewater resources with understanding the mechanisms and impacts of seasonal environmental drivers.

Methods: Empirical models were developed to solve several biologically distinct mechanisms of Salmonella sp by which seasonality can impact their interactions, including seasonal changes in replication, distribution and mortality rates.

Results: Mathematical models and field observations show that the strength and mechanisms of seasonality can alter the spread and …


Finnish Teacher Collaboration: The Behaviors, Learning, And Formality Of Teacher Collaboration, Bruce H. Eschler Dec 2016

Finnish Teacher Collaboration: The Behaviors, Learning, And Formality Of Teacher Collaboration, Bruce H. Eschler

Theses and Dissertations

Finnish teachers continue to receive significant attention among educators, educational leaders, and policy makers in the United States and around the globe. In addition, teacher collaboration continues to receive support as a meaningful part of teacher work and practice. Teacher collaboration is frequently described in various ways within different contexts. This study aims to: (a) better understand the nature of Finnish teacher collaboration by examining three teacher collaboration behaviors (sharing information and knowledge, planning, and problem-solving); (b) explore the extent to which Finnish teacher collaboration is formal (or school-required) collaboration and informal (or voluntary) collaboration; and (c) investigate …


Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Free-Field Settlements, Brian David Peterson Dec 2016

Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Free-Field Settlements, Brian David Peterson

Theses and Dissertations

Liquefaction-induced settlement can cause significant damage to structures and infrastructure in the wake of a seismic event. Predicting settlement is an essential component of a comprehensive seismic design. The inherent uncertainty associated with seismic events makes the accurate prediction of settlement difficult. While several methods of assessing seismic hazards exist, perhaps the most promising is performance-based earthquake engineering, a framework presented by the Pacific Earthquake Engineering Research (PEER) Center. The PEER framework incorporates probability theory to generate a comprehensive seismic hazard analysis. Two settlement estimation methods are incorporated into the PEER framework to create a fully probabilistic settlement estimation procedure. …


Redbeds Of The Upper Entrada Sandstone, Central Utah: Facies Analysis And Regional Implications Of Interfingered Sabkha And Fluvial Terminal Splay Sediments, Jeffery Michael Valenza Dec 2016

Redbeds Of The Upper Entrada Sandstone, Central Utah: Facies Analysis And Regional Implications Of Interfingered Sabkha And Fluvial Terminal Splay Sediments, Jeffery Michael Valenza

Theses and Dissertations

First distinguished from other sedimentary successions in 1928, the Entrada Sandstone has been the subject of numerous studies. The western extent of the formation was initially described as laterally continuous "earthy" red beds, and categorized as sub- to supratidal marine-influenced sediments. Recent workers have reexamined the sedimentary facies hosted by the Entrada Sandstone, and findings suggest purely terrestrial depositional environments. Several outcrops of the upper Entrada hosted peculiar sedimentary features, including undulatory and convex-upward, parallel-laminated bedforms, reminiscent of hummocky cross-stratification- unexpected features in a terrestrial environment. The purpose of this study was to collect detailed outcrop measurements of these and …


Decision Making In The Backcountry While Carrying A Cellular Phone, Quinn S. Linford Dec 2016

Decision Making In The Backcountry While Carrying A Cellular Phone, Quinn S. Linford

Theses and Dissertations

The purpose of this study was to gain understanding about the influence of technology, specifically cellular phones, on decision making during potentially risky situations in the backcountry. Previous research in this area is contradictory and some studies indicate technology is influencing people to take more risks while others suggest it is not. Further confounding the relationship is the fact that previous studies have found people may be taking more risk in the presence of technology were based largely on respondent perceptions, not observation data. The current study used a scenario-based decision model to examine the difference in decision making between …


Comparison Of Simulation And Hands-On Labs In Helping High School Students Learn Physics Concepts, Matthew Charles Rytting Dec 2016

Comparison Of Simulation And Hands-On Labs In Helping High School Students Learn Physics Concepts, Matthew Charles Rytting

Theses and Dissertations

The purpose of the research was to determine whether PhET simulation labs or hands-on labs were more effective in helping students learn physics concepts. This measure was done by comparing quiz scores using recall, calculation, and transfer questions. Additionally, student perceptions of learning from both hands-on and simulation lab experiences were measured. Six labs were conducted with high school physics students on the topics of momentum, energy, circuits, angular momentum, pendulums, and friction. It was found that PhET simulation labs were as effective at creating student understanding, and sometimes more effective, as measured by quizzes given after the labs. Additionally, …


A Framework For Evaluating Recommender Systems, Michael Gabriel Bean Dec 2016

A Framework For Evaluating Recommender Systems, Michael Gabriel Bean

Theses and Dissertations

Prior research on text collections of religious documents has demonstrated that viable recommender systems in the area are lacking, if not non-existent, for some datasets. For example, both www.LDS.org and scriptures.byu.edu are websites designed for religious use. Although they provide users with the ability to search for documents based on keywords, they do not provide the ability to discover documents based on similarity. Consequently, these systems would greatly benefit from a recommender system. This work provides a framework for evaluating recommender systems and is flexible enough for use with either website. Such a framework would identify the best recommender system …


An Analysis Of Support For Elementary Engineering Education Offered In The Science Teacher Journal Science And Children, Tawnicia Meservy Stocking Dec 2016

An Analysis Of Support For Elementary Engineering Education Offered In The Science Teacher Journal Science And Children, Tawnicia Meservy Stocking

Theses and Dissertations

Teachers use professional journals such as Science and Children for ideas to incorporate into their own teaching. As such the purpose of this study was to investigate the support offered for integrating engineering education into science instruction. The research methodology for this was a qualitative content analysis inferring categories based on the information presented. Twenty-three issues of the journal were read, spanning two and a half volume years. The categories that emerged were mentioning, implementing, and integrating. Deeper examples of integration were found to match the mapping and infusion strategies presented by the National Academy of Engineering and National Research …


Asymmetry Of Gains And Losses: Behavioral And Electrophysiological Measures, Diego Gonzalo Flores Dec 2016

Asymmetry Of Gains And Losses: Behavioral And Electrophysiological Measures, Diego Gonzalo Flores

Theses and Dissertations

The purpose of this research was to explore the effects of small monetary or economic gains and/or losses on choice behavior through the use of a computerized game and to determine gain/loss ratio differences using both behavioral and electrophysiological measures. Participants (N=53) played the game in several 36 minute sessions. These sessions operated with concurrent variable-interval schedules for both rewards and penalties. Previously, asymmetrical effects of gains and losses have been identified through cognitive studies, primarily due to the work of nobel laureates Daniel Kahneman and Amos Tversky (1979). They found that the effect of a loss is twice (i.e., …


Evolvability And Excess Capability As A Response To Uncertain And Future Requirements, Jeffrey Douglas Allen Dec 2016

Evolvability And Excess Capability As A Response To Uncertain And Future Requirements, Jeffrey Douglas Allen

Theses and Dissertations

Product and system designers face many challenges in the modern world. Designing products that will be subject to emerging or uncertain requirements can be one of the most significant of these challenges. A major risk associated with emerging or uncertain requirements is premature obsolescence. Large-scale, complex engineered systems, such as, aircraft, spacecraft, large seagoing vessels, communication and power systems are especially susceptible to this issue. However, this challenge is not limited to only large-scale complex systems. Even relatively simple products can suffer from premature obsolescence and even failure to be initially accepted, due to inadequately understood or changing requirements. One …


Structural Analysis Of Cell Signaling Complexes, Takuma Aoba Dec 2016

Structural Analysis Of Cell Signaling Complexes, Takuma Aoba

Theses and Dissertations

Bardet-Biedl syndrome (BBS) is a rare genetic disease that causes retinal degradation, obesity, kidney dysfunction, polydactyly, and other cilium-related disorders. To date, more than 20 BBS genes, whose mutants cause BBS phenotypes, have been identified, and eight of those (BBS1-2, 4-5, 7-9, and 18) are known to form the BBSome complex. Recent studies have revealed that the BBSome is closely involved in the trafficking of signaling proteins in the primary cilium. Mutations in BBS genes are highly pathogenic because trafficking in the primary cilium is not fully functional when BBS mutations impair assembly of the BBSome. However, the functional links …


Recognition Of Infrastructure Events Using Principal Component Analysis, Lane David Broadbent Dec 2016

Recognition Of Infrastructure Events Using Principal Component Analysis, Lane David Broadbent

Theses and Dissertations

Information Technology systems generate system log messages to allow for the monitoring of the system. In increasingly large and complex systems the volume of log data can overwhelm the analysts tasked with monitoring these systems. A system was developed that utilizes Principal Component Analysis to assist the analyst in the characterization of system health and events. Once trained, the system was able to accurately identify a state of heavy load on a device with a low false positive rate. The system was also able to accurately identify an error condition when trained on a single event. The method employed is …


Control Of Matrix Metalloproteinases In A Periodontitis Model: Molecules That Trigger Or Inhibit Mmp Production, Catalina Matias Orozco Dec 2016

Control Of Matrix Metalloproteinases In A Periodontitis Model: Molecules That Trigger Or Inhibit Mmp Production, Catalina Matias Orozco

Theses and Dissertations

In periodontitis, there is a disruption in the homeostasis of the oral microbiome by peridontopathogenic bacteria. However, while bacteria is essential for periodontitis to occur, the severity, pattern and progression of the disease is not solely determined by the microbial burden, and in fact has a lot to do with the overwhelming host inflammatory response. The response can vary even in two individuals with similar periodontopathogenic profiles. The host response leads to extracellular matrix (ECM) destruction, loss of attachment, alveolar bone resorption and eventually, edentulism. The host's reaction is orchestrated by proinflammatory cytokines and chemokines and matrix metalloproteinases (MMPs). MMPs …


How A Systematic Approach To Uncertainty Quantification Renders Molecular Simulation A Quantitative Tool In Predicting The Critical Constants For Large N-Alkanes, Richard Alma Messerly Dec 2016

How A Systematic Approach To Uncertainty Quantification Renders Molecular Simulation A Quantitative Tool In Predicting The Critical Constants For Large N-Alkanes, Richard Alma Messerly

Theses and Dissertations

Accurate thermophysical property data are crucial for designing efficient chemical processes. For this reason, the Design Institute for Physical Properties (DIPPR 801) provides evaluated experimental data and prediction of various thermophysical properties. The critical temperature (Tc), critical density (ρc), critical pressure (Pc), critical compressibility factor (Zc), and normal boiling point (Tb) are important constants to check for thermodynamic consistency and to estimate other properties. The n-alkane family is of primary interest because it is generally assumed that other families of compounds behave similarly to …


Some Spectral Properties Of A Quantum Field Theoretic Hamiltonian, Devin Burnell Mcghie Dec 2016

Some Spectral Properties Of A Quantum Field Theoretic Hamiltonian, Devin Burnell Mcghie

Theses and Dissertations

We derive the ground-state eigenvalues and eigenvectors for a simplified version of the 1-D QED single electron-photon model that Glasgow et al recently developed [2]. This model still allows for meaningful interaction between electrons and photons while keeping only the minimum needed to do so. We investigate the interesting spectral properties of this model. We determine that the eigenvectors are orthogonal as one would expect and normalize them.


A Secure, Reliable And Performance-Enhancing Storage Architecture Integrating Local And Cloud-Based Storage, Christopher Glenn Hansen Dec 2016

A Secure, Reliable And Performance-Enhancing Storage Architecture Integrating Local And Cloud-Based Storage, Christopher Glenn Hansen

Theses and Dissertations

The constant evolution of new varieties of computing systems - cloud computing, mobile devices, and Internet of Things, to name a few - have necessitated a growing need for highly reliable, available, secure, and high-performing storage systems. While CPU performance has typically scaled with Moore's Law, data storage is much less consistent in how quickly performance increases over time. One method of improving storage performance is through the use of special storage architectures. Such architectures often include redundant arrays of independent disks (RAID). RAID provides a meaningful way to increase storage performance on a variety of levels, some higher-performing than …


Life-Cycle Benefit-Cost Analysis Of Safety Related Improvements On Roadways, Jordan Browne Frustaci Dec 2016

Life-Cycle Benefit-Cost Analysis Of Safety Related Improvements On Roadways, Jordan Browne Frustaci

Theses and Dissertations

The Highway Safety Manual (HSM) lists four different methods for determining the change in crash frequency in order of reliability. Currently, the Utah Department of Transportation (UDOT) uses the fourth reliable method. The goal of this research was to develop a tool that the most reliable method mentioned in the HSM could be used to perform life-cycle benefit-cost analyses. A spreadsheet program was built that performs the HSM's Part C Predictive Method for 11 different roadway segment types mentioned in HSM using Excel macros and Visual Basic for Applications (VBA) programming. Intersections were not included in this spreadsheet program as …


Investigation Of Dynamic Biological Systems Using Direct Injection And Liquid Chromatography Mass Spectrometry, Adam Clayton Swensen Dec 2016

Investigation Of Dynamic Biological Systems Using Direct Injection And Liquid Chromatography Mass Spectrometry, Adam Clayton Swensen

Theses and Dissertations

In biological systems, small changes can have significant impacts. It is, therefore, very important to be able to identify these changes in order to understand what is occurring in the organism. In many cases, this is not an easy task. Mass spectrometry has proven to be a very useful tool in elucidating biological changes even at a very small scale. Several different mass spectrometry based techniques have been developed to discover and investigate complex biological changes. Some of these techniques, such as proteomics, have been through years of development and have advanced to the point that anyone can complete complex …


Algorithms For Learning The Structure Of Monotone And Nonmonotone Sum-Product Networks, Aaron W. Dennis Dec 2016

Algorithms For Learning The Structure Of Monotone And Nonmonotone Sum-Product Networks, Aaron W. Dennis

Theses and Dissertations

The sum-product network (SPN) is a recently-proposed generative, probabilistic model that is guaranteed to compute any joint or any marginal probability in time linear in the size of the model. An SPN is represented as a directed, acyclic graph (DAG) of sum and product nodes, with univariate probability distributions at the leaves. It is important to learn the structure of this DAG since the set of distributions representable by an SPN is constrained by it. We present the first batch structure learning algorithm for SPNs and show its advantage over learning the parameters of an SPN with fixed architecture. We …


Facies Analysis And Depositional Environments Of The Saints & Sinners Quarry In The Nugget Sandstone Of Northeastern Utah, Jesse Dean Shumway Dec 2016

Facies Analysis And Depositional Environments Of The Saints & Sinners Quarry In The Nugget Sandstone Of Northeastern Utah, Jesse Dean Shumway

Theses and Dissertations

The Saints & Sinners Quarry preserves the only known vertebrate body fossils in the Nugget Sandstone and the most diverse fauna known from the Nugget-Navajo-Aztec erg system. The fauna includes eight genera and >18,000 bone and bone fragments assignable to >76 individuals, including theropods, sphenosuchians, sphenodontians, drepanosaurs, procolophonids, and a dimorphodontid pterosaur. Cycadeoid fronds are the only plant fossils. There are two depositional environments at the site – dune and interdune, each consisting of two or more faces. The dune facies are (1) Trough Cross-Stratified Sandstone (TCS) representing dry dunes, and (2) Massive and Bioturbated Dunes (MBD) representing bioturbated, damp …


Inhibition Of Clostridium Perfringens Growth During Extended Cooling Of Cooked Uncured Roast Turkey And Roast Beef Using A Concentrated Buffered Vinegar Product And A Buffered Vinegar Product, Andrew Mitchell Smith Dec 2016

Inhibition Of Clostridium Perfringens Growth During Extended Cooling Of Cooked Uncured Roast Turkey And Roast Beef Using A Concentrated Buffered Vinegar Product And A Buffered Vinegar Product, Andrew Mitchell Smith

Theses and Dissertations

This research evaluates the effectiveness of a concentrated, buffered vinegar product (CBV) and a simple buffered vinegar product (BV) for controlling Clostridium perfringens outgrowth during extended cooling times of ready-to-eat roast turkey and roast beef respectively. Whole turkey breasts and beef inside rounds were injected with a typical brine, then ground and mixed with CBV (0.0, 2.01, 2.70 and 3.30% wt/wt) or BV (0.0, 1.75, 2.25, and 3.75% wt/wt) and a three-strain C. perfringens spore cocktail to a detectable level of ca. 2-3 log CFU/g. The meat was divided into 10g portions and vacuum packaged and stored frozen until tested. …


Integrated Design Of Downwind Land-Based Wind Turbines Using Analytic Gradients, Andrew Ning, Derek Petch Dec 2016

Integrated Design Of Downwind Land-Based Wind Turbines Using Analytic Gradients, Andrew Ning, Derek Petch

Faculty Publications

Wind turbines are complex systems where component-level changes can have significant system-level effects. Effective wind turbine optimization generally requires an integrated analysis approach with a large number of design variables. Optimizing across large variable sets is orders of magnitude more efficient with gradient-based methods as compared to gradient-free method, particularly when using exact gradients. We have developed a wind turbine analysis set of over 100 components where 90% of the models provide numerically exact gradients through symbolic differentiation, automatic differentiation, and adjoint methods. This framework is applied to a specific design study focused on downwind land-based wind turbines.

Downwind machines …


Direct Band Gap Measurements, John Ryan Peterson Nov 2016

Direct Band Gap Measurements, John Ryan Peterson

Student Works

This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis and then explain the mechanism of photoluminsecence used to measure indirect band gap energies of semiconductors. Our experimental setup is shown. Direct band gaps of lead sulfide quantum dots synthesized in ferritin are reported. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations of the reactants. We compare stability of quantum dots in ferritin to quantum dots synthesized without …


Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, Zoe Hughes Nov 2016

Determining The Index Of Refraction Of Aluminum Fluoride In The Ultra Violet Spectrum, Zoe Hughes

Student Works

A NASA project called Large UV/Optical/Infrared Surveyor (LUVOIR) is looking into ways to coat a mirror for a new space telescope. We contributed to this project by investigating aluminum fluoride (AlF3) as a possible coating for the mirror. We measured the index of refraction of AlF3 in the wavelength range 6 – 49.5 nm by testing three sample mirrors, each made up of a silicon wafer with a coating of AlF3. We took data at the Advanced Light Source (ALS) in Berkeley, California and in the laboratory at Brigham Young University (BYU). There are discrepancies …


Quantum Dot Band Gap Measurements, John Ryan Peterson Nov 2016

Quantum Dot Band Gap Measurements, John Ryan Peterson

Student Works

This presentation was given during the summer of 2016 as part of the BYU REU program funded by the NSF. Here I give a brief explanation of our quantum dot synthesis as well as explain the use of absorption spectroscopy to measure indirect band gap energies of semiconductors. Our experimental setup is shown and recent improvements are explained. We report indirect band gaps of quantum dots containing varying amounts of cobalt oxide and manganese oxide and synthesized in the protein ferritin. The data show that the band gap can be tuned arbitrarily in a certain range by varying the concentrations …