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Full-Text Articles in Physical Sciences and Mathematics

Evaluating The Historical Accuracy Of Blackwork Embroidery With Fractal Analysis, Rhiannon Cire May 2021

Evaluating The Historical Accuracy Of Blackwork Embroidery With Fractal Analysis, Rhiannon Cire

Undergraduate Theses and Capstone Projects

The intricate monochromatic embroidery that graced the collars and cuffs of Renaissance nobility and domestic materials from that era has been little studied beyond the historical costuming and crafting communities. This style, known as blackwork, for it was traditionally done in black silk on white linen, exemplifies how complex and visually-appealing designs can arise from repetition of simple forms, often demonstrating the fractal property of self-similarity. Though most blackwork patterns are not true fractals, fractal analysis offers a means of objectively quantifying their complexity and new lens through which to examine this embroidery technique. The purpose of this study was …

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Resources For Supporting Mathematics And Data Science Instructors During Covid-19, Eduardo C. Balreira, C. Hawthorne, G. Stadnyk, Z. Teymuroglu, M. Torres, J. R. Wares May 2021

Resources For Supporting Mathematics And Data Science Instructors During Covid-19, Eduardo C. Balreira, C. Hawthorne, G. Stadnyk, Z. Teymuroglu, M. Torres, J. R. Wares

Mathematics Faculty Research

In late May of 2020, a few months after the raging COVID-19 pandemic forced university faculty to quickly switch to online teaching, the Associated Colleges of the South (ACS) released a call for grant applications to support working groups "to help faculty within our consortium who will be teaching during the pandemic (e.g., from hybrid courses with some remote/online components to fully remote/online courses; socially distanced face-to-face courses)." We replied to this call and the ACS awarded the six of us (from four ACS schools) a Summer Rapid Response Grant in early June. The grant funded our efforts to create …

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A Zenith Z-100 Emulator, Joseph Matta May 2021

A Zenith Z-100 Emulator, Joseph Matta

Master’s Theses and Projects

The Zenith Z-100 computer was released by the Zenith Data Systems Corporation in 1982 as a competitor to the IBM PC. There are no known complete software emulations of the system. A Z-100 emulator is considered to be complete if it runs all functions of its monitor ROM BIOS program and is able to boot and run its two operating systems. One reason previous emulation attempts are not complete is that they ineffectively implement the floppy disk controller, preventing a proper transfer of the operating system from disk into memory. This project is an attempt to write a complete emulation …

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Order Relations Are Ubiquitously Fundamental: Alexandrov(-Zeeman) Theorem Extended From Space-Time Physics To Logical Reasoning And Decision Making, Vladik Kreinovich, Olga Kosheleva, Laxman Bokati, Laura Berrout May 2021

Order Relations Are Ubiquitously Fundamental: Alexandrov(-Zeeman) Theorem Extended From Space-Time Physics To Logical Reasoning And Decision Making, Vladik Kreinovich, Olga Kosheleva, Laxman Bokati, Laura Berrout

Departmental Technical Reports (CS)

In all areas of human activity, there are natural ordering relations: causality in space-time physics, preference in decision making, and logical inference in reasoning. In space-time physics, a 1950 theorem by A. D. Alexandrov proved that causality relation is fundamental: many other features, including numerical characteristics of time and space, can be reconstructed from this relation. In this paper, we provide simple proofs that, similarly, the corresponding ordering relations are fundamental in decision making and in logical reasoning.

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De-Icing Impacts On The Danforth Campus, Spring 2021, Nick Charlton-Perrin, Katie Halwachs, Jane Hrinya, Jake Muilenberg, Patrick Wiecko May 2021

De-Icing Impacts On The Danforth Campus, Spring 2021, Nick Charlton-Perrin, Katie Halwachs, Jane Hrinya, Jake Muilenberg, Patrick Wiecko

Sustainability Exchange

De-Icing Impacts on the Danforth Campus, Sustainability Exchange, Washington University in St. Louis, Spring 2021.

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Esg Investing, Spring 2021, Joey Cook, Jess King, Ricky Kuehn, Yilin Li, Sam Shonfeld, Alex Staton May 2021

Esg Investing, Spring 2021, Joey Cook, Jess King, Ricky Kuehn, Yilin Li, Sam Shonfeld, Alex Staton

Sustainability Exchange

ESG Investing Project for Sustainability Exchange, Washington University in St. Louis, Spring 2021

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Bird Strike Mitigation, Spring 2021, Lizzy Washington University In St. Louis, Jonathan Kacvinsky, Sam Pensiero, Landon Tafoya, Reid Watson May 2021

Bird Strike Mitigation, Spring 2021, Lizzy Washington University In St. Louis, Jonathan Kacvinsky, Sam Pensiero, Landon Tafoya, Reid Watson

Sustainability Exchange

Bird Strike Migration Project for Sustainability Exchange, Washington University in St. Louis, Spring 2021

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Retail Trading And Stock Volatility: The Case Of Robinhood, Cooper Jones May 2021

Retail Trading And Stock Volatility: The Case Of Robinhood, Cooper Jones

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

We examine the relation between Robinhood usership and stock market volatility. We show that daily fluctuations in Robinhood usership, which is used to proxy retail trading, significantly influence various measures of volatility. These results might suggest that Robinhood users contribute to noise trading as they are generally individuals trading on name recognition, media coverage, popularity, and familiarity of products, rather than on fundamental values. In our empirical approach, we find that the percentage increase in Robinhood usership Granger causes increases in daily stock volatility.

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Functionalized Carbon Nanotubes (Cnts) For Water And Wastewater Treatment: Preparation To Application, Mian Muhammad-Ahson Aslam, Hsion-Wen Kuo, Walter Den, Muhammad Usman, Muhammad Sultan, Hadeed Ashraf May 2021

Functionalized Carbon Nanotubes (Cnts) For Water And Wastewater Treatment: Preparation To Application, Mian Muhammad-Ahson Aslam, Hsion-Wen Kuo, Walter Den, Muhammad Usman, Muhammad Sultan, Hadeed Ashraf

Water Resources Science and Technology Faculty Publications

As the world human population and industrialization keep growing, the water availability issue has forced scientists, engineers, and legislators of water supply industries to better manage water resources. Pollutant removals from wastewaters are crucial to ensure qualities of available water resources (including natural water bodies or reclaimed waters). Diverse techniques have been developed to deal with water quality concerns. Carbon based nanomaterials, especially carbon nanotubes (CNTs) with their high specific surface area and associated adsorption sites, have drawn a special focus in environmental applications, especially water and wastewater treatment. This critical review summarizes recent developments and adsorption behaviors of CNTs …

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Mathematical Models Of Covid-19, Kate Faria May 2021

Mathematical Models Of Covid-19, Kate Faria

Honors Program Theses and Projects

For more than a year, the COVID-19 pandemic has been a major public health issue, affecting the lives of most people around the world. With both people’s health and the economy at great risks, governments rushed to control the spread of the virus. Containment measures were heavily enforced worldwide until a vaccine was developed and distributed. Although researchers today know more about the characteristics of the virus, a lot of work still needs to be done in order to completely remove the disease from the population. However, this is true for most of the infectious diseases in existence, including Influenza, …

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Mining And Managing Big Data Refactoring For Design Improvement: Are We There Yet?, Eman Abdullah Alomar, Mohamed Wiem Mkaouer, Ali Ouni May 2021

Mining And Managing Big Data Refactoring For Design Improvement: Are We There Yet?, Eman Abdullah Alomar, Mohamed Wiem Mkaouer, Ali Ouni

Articles

Refactoring is a set of code changes applied to improve the internal structure of a program, without altering its external behavior. With the rise of continuous integration and the awareness of the necessity of managing technical debt, refactoring has become even more popular in recent software builds. Recent studies indicate that developers often perform refactorings. If we consider all refactorings performed across all projects, this consists of the refactoring knowledge that represents a rich source of information that can be useful for both developers and practitioners to better understand how refactoring is being applied in practice. However, mining, processing, and …

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Refactoring Practices In The Context Of Modern Code Review: An Industrial Case Study At Xerox, Eman Abdullah Alomar, Hussein Alrubaye, Mohamed Wiem Mkaouer, Ali Ouni, Marouane Kessentini May 2021

Refactoring Practices In The Context Of Modern Code Review: An Industrial Case Study At Xerox, Eman Abdullah Alomar, Hussein Alrubaye, Mohamed Wiem Mkaouer, Ali Ouni, Marouane Kessentini

Articles

Modern code review is a common and essential 2 practice employed in both industrial and open-source projects 3 to improve software quality, share knowledge, and ensure con4 formance with coding standards. During code review, developers 5 may inspect and discuss various changes including refactoring 6 activities before merging code changes in the code base. To date, 7 code review has been extensively studied to explore its general 8 challenges, best practices and outcomes, and socio-technical 9 aspects. However, little is known about how refactoring activities 10 are being reviewed, perceived, and practiced. 11 This study aims to reveal insights into …

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Finding The Needle In A Haystack: On The Automatic Identification Of Accessibility User Reviews, Eman Abdullah Alomar, Wajdi Aljedaani, Murtaza Tamjeed, Mohamed Wiem Mkaouer, Yasime Elglaly May 2021

Finding The Needle In A Haystack: On The Automatic Identification Of Accessibility User Reviews, Eman Abdullah Alomar, Wajdi Aljedaani, Murtaza Tamjeed, Mohamed Wiem Mkaouer, Yasime Elglaly

Articles

In recent years, mobile accessibility has become an important trend with the goal of allowing all users the possibility of using any app without many limitations. User reviews include insights that are useful for app evolution. However, with the increase in the amount of received reviews, manually analyzing them is tedious and time-consuming, especially when searching for accessibility reviews. The goal of this paper is to support the automated identification of accessibility in user reviews, to help technology professionals in prioritizing their handling, and thus, creating more inclusive apps. Particularly, we design a model that takes as input accessibility user …

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Voltage-Controlled Magnetic Anisotropy In Antiferromagnetic Mgo-Capped Mnpt Films, P. H. Chang, Wuzhang Fang, T. Ozaki, Kirill Belashchenko May 2021

Voltage-Controlled Magnetic Anisotropy In Antiferromagnetic Mgo-Capped Mnpt Films, P. H. Chang, Wuzhang Fang, T. Ozaki, Kirill Belashchenko

Kirill Belashchenko Publications

The magnetic anisotropy in MgO-capped MnPt films and its voltage control are studied using first-principles calculations. Sharp variation of the magnetic anisotropy with film thickness, especially in the Pt-terminated film, suggests that it may be widely tuned by adjusting the film thickness. In thick films the linear voltage control coefficient is as large as 1.5 and -0.6 pJ/Vm for Pt-terminated and Mn-terminated interfaces, respectively. The combination of a widely tunable magnetic anisotropy energy and a large voltage-control coefficient suggest that MgO-capped MnPt films can serve as a versatile platform for magnetic memory and antiferromagnonic applications.

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Vignette 12: The Blob, Nicholas Bond May 2021

Vignette 12: The Blob, Nicholas Bond

Institute Publications

A marine heat wave of unprecedented severity, areal extent and duration occurred in the Northeast Pacific Ocean during 2014-2016. This event, known as the “Blob,” had a wide variety of far- ranging effects on physical, chemical, and biological ocean properties. Because the Blob was such a massive perturbation, it represents an attractively large signal for inquiry in the Salish Sea. It represents a dress rehearsal for typical conditions in future decades due to global climate change.

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Comparing Generic And Community-Situated Crowdsourcing For Data Validation In The Context Of Recovery From Substance Use Disorders, Sabirat Rubya, Joseph Numainville, Svetlana Yarosh May 2021

Comparing Generic And Community-Situated Crowdsourcing For Data Validation In The Context Of Recovery From Substance Use Disorders, Sabirat Rubya, Joseph Numainville, Svetlana Yarosh

Computer Science Faculty Research and Publications

Targeting the right group of workers for crowdsourcing often achieves better quality results. One unique example of targeted crowdsourcing is seeking community-situated workers whose familiarity with the background and the norms of a particular group can help produce better outcome or accuracy. These community-situated crowd workers can be recruited in different ways from generic online crowdsourcing platforms or from online recovery communities. We evaluate three different approaches to recruit generic and community-situated crowd in terms of the time and the cost of recruitment, and the accuracy of task completion. We consider the context of Alcoholics Anonymous (AA), the largest peer …

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Sub-Surface Structural Analysis Of The Appalachian Basin In Morrow County, Ohio, Adrian Isaiah-Sias Valdez May 2021

Sub-Surface Structural Analysis Of The Appalachian Basin In Morrow County, Ohio, Adrian Isaiah-Sias Valdez

Electronic Theses and Dissertations

Located in the western most region of the Appalachian Basin, Morrow County, Ohio, was once one of the largest oil-producing regions in the nation and continually produces today. To date, approximately 30 million barrels of oil and 6.5 billion cubic feet of gas have been produced, primarily from the Copper Ridge Dolomite. Past studies suggest that regional remnant doming within the Copper Ridge accounts for production, however it is hypothesized that faulting within the basement rock exerts an important control on trapping and migration of hydrocarbons. In order to gain insight into the underlying structure and the causes of significant …

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Vignette 16: Vulnerability And Climate Change Adaptation, Northwest Indian Fisheries Commission, Jamestown S'Klallam Tribe May 2021

Vignette 16: Vulnerability And Climate Change Adaptation, Northwest Indian Fisheries Commission, Jamestown S'Klallam Tribe

Institute Publications

The 2013 Jamestown Climate Vulnerability Assessment and Adaptation Plan provides an assessment of vulnerabilities of tribal resources to the negative impacts of climate change. The plan also identifies adaptation measures that the tribe is working to complete. Sea level rise, ocean acidification and climate models show potential for increased risks to critical habitats, tribal infrastructure and tribal health. As one of the first tribes in western Washington to complete a climate adaptation plan and vulnerability assessment, the Jamestown S’Klallam Tribe has identified and prioritized areas where changing climate conditions will leave tribal resources, infrastructure, economy and health most vulnerable, Climate …

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A Comparison Of Word Embedding Techniques For Similarity Analysis, Tyler Gerth May 2021

A Comparison Of Word Embedding Techniques For Similarity Analysis, Tyler Gerth

Computer Science and Computer Engineering Undergraduate Honors Theses

There have been a multitude of word embedding techniques developed that allow a computer to process natural language and compare the relationships between different words programmatically. In this paper, similarity analysis, or the testing of words for synonymic relations, is used to compare several of these techniques to see which performs the best. The techniques being compared all utilize the method of creating word vectors, reducing words down into a single vector of numerical values that denote how the word relates to other words that appear around it. In order to get a holistic comparison, multiple analyses were made, with …

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Applying Emotional Analysis For Automated Content Moderation, John Shelnutt May 2021

Applying Emotional Analysis For Automated Content Moderation, John Shelnutt

Computer Science and Computer Engineering Undergraduate Honors Theses

The purpose of this project is to explore the effectiveness of emotional analysis as a means to automatically moderate content or flag content for manual moderation in order to reduce the workload of human moderators in moderating toxic content online. In this context, toxic content is defined as content that features excessive negativity, rudeness, or malice. This often features offensive language or slurs. The work involved in this project included creating a simple website that imitates a social media or forum with a feed of user submitted text posts, implementing an emotional analysis algorithm from a word emotions dataset, designing …

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Making Valid Inferences With Decision Tree, George Ekow Quaye May 2021

Making Valid Inferences With Decision Tree, George Ekow Quaye

Open Access Theses & Dissertations

HypoThesis testing and Confidence Interval (CI) estimates are key statistics in predicting future values in data analysis. Most often, CI estimates are directly obtained from the summary statistics of a particular statistical methodology output. However, when it comes to the summary of decision tree outputs, these CI estimates are not directly obtained. So a na\"{i}ve way of making node-level inference is to construct a $(1-\alpha) \times 100\%$ confidence interval for a node mean $\bar{y}_t$ using the relation: $\bar{y}_t \, \pm \, z_{1-\alpha/2} \, \frac{s_t}{\sqrt{n_t}}$, where $\bar{y}_t$ is the node mean and $s_t$ is the standard deviation estimates from the decision …

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Organic Synthesis For Solving Clinical Conundrums Of Drug Activation And For Facilitating Natural Product Drug Discovery, Elkin Libardo Romero May 2021

Organic Synthesis For Solving Clinical Conundrums Of Drug Activation And For Facilitating Natural Product Drug Discovery, Elkin Libardo Romero

Open Access Theses & Dissertations

Organic chemistry is an exploratory world in which chemists translate their knowledge by creating new molecules and explore their biological and physical properties. For the past three years, our research has been focused on organic synThesis and chemical biology to solve challenges in this area. Two major approaches have been faced: First, the chemical synThesis of the active metabolite of antithrombotic prodrug Plavix (clopidogrel). Clopidogrel (CPG) has been widely used as an antithrombotic prodrug, which undergoes extensive metabolism in patients; among it, only a trivial portion is converted through a series of cytochrome P450 (CYP)-catalyzed thiophene degradation to form active …

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High Frequency Electron Spin Resonance Investigations On Quasi-Two-Dimensional Chromium Halide Magnets, Christian Saiz May 2021

High Frequency Electron Spin Resonance Investigations On Quasi-Two-Dimensional Chromium Halide Magnets, Christian Saiz

Open Access Theses & Dissertations

Broadening the knowledge and understanding on the magnetic correlations in van der Waals layered magnets is critical in realizing their potential next-generation applications in devices such as spintronics. In this study, we employ high frequency (ν = 120 GHz, 240 GHz) electron spin resonance (ESR) spectroscopy on plate-like CrX3 (where X = Cl, Br, I) to gain insight into the magnetic interactions as a function of temperature (200 – 4.4 K) and the angle of rotation θ (degrees). We find that the temperature dependence of the ESR linewidth is well described by the Ginzburg-Landau critical model, indicative of antiferromagnetic correlations …

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Multiplicative And Additive Arithmetic Functions And Formal Power Series, John Byron Snell May 2021

Multiplicative And Additive Arithmetic Functions And Formal Power Series, John Byron Snell

Open Access Theses & Dissertations

The theory of arithmetic functions and the theory of formal power series are classical andactive parts of mathematics. Algebraic operations on sets of arithmetic functions, called convolutions, have an important place in the theory of arithmetic functions. The theory of formal power series also has its place firmly anchored in abstract algebra. A first goal of this Thesis will be to present a parallelism of known characterizations of the concepts of multiplicative and additive for arithmetic functions (Theorems 2.1.2 and 2.2.3) on the one hand and for formal power series on the other (Theorems 3.4.3 and 3.4.4). Therefore, in Chapter …

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Digital Twin Technology Applications For Transportation Infrastructure - A Survey-Based Study, Hector Cruz May 2021

Digital Twin Technology Applications For Transportation Infrastructure - A Survey-Based Study, Hector Cruz

Open Access Theses & Dissertations

In the past couple of decades, various industries have taken advantage of emerging advanced technologies, such as digital twin (DT), to find more effective solutions in their respective areas. In the transportation infrastructure sector, the concept and implementation of DT technologies are slowly gaining traction but lagging behind other major industries. To better understand the limitations, opportunities and challenges for the adoption of DT in this sector, a survey questionnaire was distributed to collect information from industry professionals involved in transportation infrastructure projects. The purpose of this study is to understand how DT technology is being perceived by the industry. …

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Novel N-Derivatized-7-Nitroindolines For The Synthesis Of Photocleavable Crosslinkers, And For Solid Phase Peptide Synthesis, Hector Patricio Del Castillo May 2021

Novel N-Derivatized-7-Nitroindolines For The Synthesis Of Photocleavable Crosslinkers, And For Solid Phase Peptide Synthesis, Hector Patricio Del Castillo

Open Access Theses & Dissertations

7-Nitroindoline-based photochemistry has focused mostly on N-acyl-7-nitroindolines, which have been used as photocleavable protecting groups for carboxylic acids that can be efficiently removed by illumination with UV-light. They offer an alternative to the more commonly used o-nitrobenzyl-based photocleavable protecting groups. N-acyl-7-nitroindolines can also be used as photochemical acylating agents in inert solvents. For example, they have found application in peptide fragment condensation, the convergent synThesis of N-glycopeptides, and the synThesis of peptide thioesters, forming amide and thioester bonds with amine and thiol nucleophiles, respectively, under neutral conditions. The photochemical activation of N-acyl-7-nitroindolines can occur with UV light (λ = 350 …

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Impact Of Various Hydrophobic Cargoes On The Structural Properties Of Pluronic-F127 Based Micelles Near The Standard Critical Transition Zone, Tahmida Raheen Iqbal May 2021

Impact Of Various Hydrophobic Cargoes On The Structural Properties Of Pluronic-F127 Based Micelles Near The Standard Critical Transition Zone, Tahmida Raheen Iqbal

Open Access Theses & Dissertations

Pluronic F-127 is a triblock copolymer (PEO-PPO-PEO) that can form a micelle at critical micelle concentration (CMC). CMC for Pluronic F-127 is 0.7% at 25 0C. Micelles are lipid molecules that can arrange themselves in a spherical form in an aqueous solution with a hydrophobic core and hydrophilic shell. Pluronic F-127 can encapsulate poor water-soluble drugs and administrate the medicine to the targeted area with a controlled drug release rate and low toxicity. The purpose of this study is to understand the structural variation in Pluronic F-127 micelles after loading with different hydrophobic cargoes (alkanes, fatty acids, anticancer therapeutic agents). …

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Robust Variable Selection In Multiple Linear Regression Via Penalized Least Trimmed Squares., Reagan Kesseku May 2021

Robust Variable Selection In Multiple Linear Regression Via Penalized Least Trimmed Squares., Reagan Kesseku

Open Access Theses & Dissertations

Variable selection has been studied using different approaches. Its growing importance lies in numerous applications to high-dimensional data from experiments and natural phenomena. Often, models are to be constructed from such data based on significant variables for estimation or prediction purposes. This demands not just any variable selectionmethod, but one that is robust, computationally efficient and with other desirable statistical properties. Besides the high-dimensionality of such data, the presence of outliers is common due to heterogeneous sources. Though outliers often contain useful information, they can unduly influence non-robust estimators to produce misleading results. This is the case for ordinary least …

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Deep Learning-Based Object Detection Of Barley Seeds, Jiayi Li May 2021

Deep Learning-Based Object Detection Of Barley Seeds, Jiayi Li

Theses and Dissertations

Computer vision techniques have been widely used in the food manufacturing industry today due to their speed, convenience, and low labor cost. As an important raw material in beer, barley seeds largely determine the flavor and taste of the beer brewing process. To ensure the quality of beer, beer brewers will strictly screen the varieties of barley seeds and ensure the purity of malt. Traditional manual detection needs a lot of professional training, and because of the high similarity between different kinds of barley seeds, tedious and time-consuming manual detection leads to a high error rate. However, chemical testing requires …

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Machine Learning Representations For Optimization Of Process Systems, Logan Watts May 2021

Machine Learning Representations For Optimization Of Process Systems, Logan Watts

Chemical Engineering Undergraduate Honors Theses

The optimal operation of chemical processes provides the foundation for optimization problems to determine the most effective way to operate or design a given process. Chemical processes can be represented as nonlinear systems of equations with decision variables, resulting in a problem that can be solved through nonlinear solvers. The downfalls of nonlinear solvers create the need for improved methods of finding globally optimal solutions to the design or operation of a chemical process. The project will seek to evaluate the use of artificial neural networks to approximate nonlinear systems of equations for the purpose of optimizing chemical processes. The …

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