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A Multi-Fidelity Approach To Address Multi-Objective Constrained Mixed-Discrete Nonlinear Programming Problems With Application To Greener Aircraft Design, Samarth Jain May 2018

A Multi-Fidelity Approach To Address Multi-Objective Constrained Mixed-Discrete Nonlinear Programming Problems With Application To Greener Aircraft Design, Samarth Jain

Open Access Theses

Engineering problems often involve solving constrained multi-objective Mixed-Discrete Nonlinear Programming (MDNLP) problems. These problems are inherently difficult to solve given the presence of multiple competing objectives, nonlinear objective and constraint functions, mixed-discrete type design variables, and expensive analysis tools. This work presents a multi-fidelity approach that addresses all these features together and exhibits its efficacy to solve constrained multi-objective MDNLP problems within a reasonable computational budget. The work addresses the high computational cost drawback associated with a previously developed “hybrid multi-objective optimization approach” that combines a Genetic Algorithm (GA) with the gradient-based Sequential Quadratic Programming (SQP) algorithm. The multi-fidelity hybrid …

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Effects Of Plant Growth Regulators On Salinity Tolerance In Perennial Ryegrass, Zhongjie Ji May 2018

Effects Of Plant Growth Regulators On Salinity Tolerance In Perennial Ryegrass, Zhongjie Ji

Open Access Theses

Salinity stress is a major abiotic stress that affects plant growth and development. Application of plant growth regulators (PGRs) can improve salinity tolerance. The objective of this study was to investigate effects of PGRs effect on growth and physiology of perennial ryegrass (Lolium Perenne) and alterations of endogenous plant hormone under salinity stress in perennial ryegrass cultivars. The reduced plant height, dry weight and fresh weight, and K+ concentration and increased Na+ concentration were observed in four cultivars of Brightstar SLT, Catalina, Inspire and SR4660ST under both 100 mM and 200 mM NaCl. No obvious PGR effects were found in …

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Dyadic Interactions In Children Exhibiting The Broader Autism Phenotype, Ashleigh M. Kellerman May 2018

Dyadic Interactions In Children Exhibiting The Broader Autism Phenotype, Ashleigh M. Kellerman

Open Access Theses

In families raising a child with an autism spectrum disorder (ASD), infant siblings are at elevated risk for ASD and other developmental concerns including subclinical ASD features, often called the Broader Autism Phenotype (BAP). Recognizing the importance of parent-child social interactions in early development and the known social difficulties associated with BAP, the present study aimed to expand our developmental understanding of the BAP by (1) examining performance on standardized measures, and (2) describing dyadic characteristics to determine if the BAP group is distinguishable from the TYP group on select dyadic constructs. As part of a prospective study, dyads were …

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Analyzing The Effect Of Policy, Field Geometry, And Environmental Criteria On Switchgrass Breakeven Price In A Landscape Design System, Thomas Karmel May 2018

Analyzing The Effect Of Policy, Field Geometry, And Environmental Criteria On Switchgrass Breakeven Price In A Landscape Design System, Thomas Karmel

Open Access Theses

A landscape design system (LDS) combines subfield management and precision agriculture to integrate a bioenergy crop into portions of a row crop field that is deemed unprofitable, environmentally unsustainable, or both. This analysis utilizes switchgrass as the bioenergy crop, and calculates the switchgrass breakeven price for inclusion in a LDS with corn. Field geometry is the arrangement of switchgrass subfields in a LDS. We utilize economic and environmental criteria to create multiple geometries for each field and calculate each one’s subsequent switchgrass breakeven price. This tests whether economic and environmental incentives align for a given field. We find the overlap …

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Tweets Of Wrath: Assessing Social Media Influence In Organizational Crisis, Megan Courtaney Kendall May 2018

Tweets Of Wrath: Assessing Social Media Influence In Organizational Crisis, Megan Courtaney Kendall

Open Access Theses

For businesses and organizations, public perception is a critical factor in determining the effectiveness of crisis response strategies in mitigating reputational damage. However, current crisis literature offers little investigation into how public response found on social media can be measured and assessed. This case study seeks to better understand the role of online public perception in crisis and how social media are disrupting crisis communication strategies. On April 9th, 2017, United Airlines faced global outrage in an exceptional case that is both relevant and interesting in considering how online publics engaged with the crisis via social media after a video …

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Investigation Into High Explosive Particle Dynamics Under Impact Loading, Nicholas E. Kerschen May 2018

Investigation Into High Explosive Particle Dynamics Under Impact Loading, Nicholas E. Kerschen

Open Access Theses

The shock or impact initiation of high explosives (HEs) at the particle scale remains of great interest to the military and other industries, yet there lacks an exhaustive understanding of the mechanisms by which this occurs. The most prevalent hypothesis to explain this phenomenon is termed hot spot theory. Hot spot theory proposes that energy inside the HE consolidates at locally concentrated sites due to an impact and that these localized pockets create the adequate temperature required for ignition. However, there is a dearth of experimental data at the microscale where hot spots occur. This study focuses on investigating the …

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Stretchable Thin-Film Electronics For Wearable Biomedical Applications, Min Ku Kim May 2018

Stretchable Thin-Film Electronics For Wearable Biomedical Applications, Min Ku Kim

Open Access Theses

Stretchable Thin-Film electronics which are mechanically reinforced by interconnected nanocomposite elastomers of high quality metallic nanowires deliver conducting paths for electronics. Due to the mechanical properties of the networked nanowires, the resistance against crack and edge delamination was improved. Theoretical and experimental studies demonstrates its enhancement in stretchability, adhesion to skin and resistance against crack generation and propagation. Such nanocomposite elastomer structures mechanically strengthened with networked nanocomposite can be fabricated into a class of biomedical devices capable of electrophysiological monitoring via the skin.

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Marchenko Redatuming And Imaging For Carbon Sequestration Monitoring: Application To The Frio Experiment., Mert Sinan Recep Kiraz May 2018

Marchenko Redatuming And Imaging For Carbon Sequestration Monitoring: Application To The Frio Experiment., Mert Sinan Recep Kiraz

Open Access Theses

The application of Marchenko redatuming and imaging for carbon sequestration monitoring using both synthetic and observed data from the Frio carbon sequestration experiment is investigated in this study. The Marchenko approach can be used to eliminate disturbing effects of overburden structure by placing virtual sources near target structures in the subsurface for seismic imaging. Two synthetic examples, one with a simple layered velocity model and one with a velocity model derived from the first arrival travel-times from the Frio carbon sequestration experiment are first investigated. Marchenko redatuming and inversion is then applied to the observed data from the Frio experiment …

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The Role Of Direct Insolation And Near-Surface Moisture Advection In The Recovery Of Cape On 31 March 2016 During Vortex-Southeast, Allison Lafleur May 2018

The Role Of Direct Insolation And Near-Surface Moisture Advection In The Recovery Of Cape On 31 March 2016 During Vortex-Southeast, Allison Lafleur

Open Access Theses

The relative roles of direct insolation and near-surface moisture advection in the recovery of convective available potential energy (CAPE) on 31 March 2016 in northern Alabama are examined using VORTEX-Southeast observations and numerical simulations. In between rounds of nontornadic morning storms and tornadic evening storms, CAPE over the VORTEX-Southeast domain increased from near zero to at least 500 J kg-1. A timeline of the day’s events is provided with a focus on the evolution of the lower levels of the atmosphere. In particular, we focus on its responses to solar insolation and moisture advection, which are hypothesized as the main …

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The Reliability Of Symphony Link In Emergency Scenarios, Anna Larson May 2018

The Reliability Of Symphony Link In Emergency Scenarios, Anna Larson

Open Access Theses

A wireless network is needed that can be taken into natural disaster areas. This network could use rapid requirements of group communication and be closely monitored with an assortment of sensors, for example displacement, temperature, noises, concentration, and pressure of chemicals (Chen et al., 2013). Disaster prevention is essential in any country, especially in metropolitan areas. Ad-hoc sensor networks have the ability to offer first responders with a quick deployable, economical, and dependable method to collect worthwhile knowledge in terms of possibility of people trapped within a comprised structure, and the condition of the area. From the statistical analysis, we …

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Micro-Scale Waste Heat Recovery From Stationary Internal Combustion Engines By Sub-Critical Organic Rankine Cycle Utilizing Scroll Machinery, Alejandro C. Lavernia May 2018

Micro-Scale Waste Heat Recovery From Stationary Internal Combustion Engines By Sub-Critical Organic Rankine Cycle Utilizing Scroll Machinery, Alejandro C. Lavernia

Open Access Theses

The movement towards renewable energy sources has created new challenges for energy production and has promoted the concept of distributed energy production. High efficiency Generators for Small Electrical and Thermal Systems (GENSETS) provide a viable solution to residential-scale power production at low cost. In an effort to improve the energy production efficiency of small scale internal combustion engine generators, a waste heat recovery (WHR) bottoming cycle can boost the operating efficiency of such systems by up to 7%. Organic Rankine Cycle (ORC) technology is a popular method of achieving WHR from low temperature heat sources. However, the application of ORC …

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Air Traffic Delay Prediction Based On Machine Learning And Delay Propagation, Meng Li May 2018

Air Traffic Delay Prediction Based On Machine Learning And Delay Propagation, Meng Li

Open Access Theses

Flight Delay creates significant problems in the current aviation system. Methods are needed to analyze the manner in which delay propagates in the airport networks. Traditional methods are inadequate to the task. This paper presented a new machine learning based air traffic delay prediction model that combined multi-label random forest classification and approximated delay propagation model. To improve the prediction performance, an optimal feature selection process is introduced and demonstrated to have better performance than directly using all the features of available datasets. Departure delay and late arriving aircraft delay are shown to be the most critical features for delay …

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The Acute Effect Of Isoflurane And Propofol On The Olfactory-Cognitive Ability Of Brown Root Rot Disease Fungus Detection Dogs, Jessie Lien May 2018

The Acute Effect Of Isoflurane And Propofol On The Olfactory-Cognitive Ability Of Brown Root Rot Disease Fungus Detection Dogs, Jessie Lien

Open Access Theses

Scent detection dogs may get injured when performing their tasks and anesthesia is needed for medical attention of these dogs. Currently there is no study evaluating the effect of anesthesia on the olfactory ability of scent detection dogs. This study examined the effects of two commonly used anesthetics, isoflurane (an inhalant agent) and propofol (an injectable agent), on canine olfactory-cognitive circuitry in detecting brown root rot fungus (BRR). The study also evaluated a novel linear route scent detection system utilizing a leash suspended by a guide wire to minimize human hints in dogs. We hypothesized that 1) both anesthetics would …

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Dynamic Behavior Of Additively Manufactured 316l Stainless Steel, Cody D. Kirk May 2018

Dynamic Behavior Of Additively Manufactured 316l Stainless Steel, Cody D. Kirk

Open Access Theses

Additive manufacturing has become an enabling technology for making extremely complicated engineered structures that were once impossible to produce. However, the manufacturing process inherently introduces a multitude of variables that can affect the mechanical performance of the structure. In order to truly understand the mechanical response of the material it must be characterized under similar conditions. Therefore, it is necessary to perform high strain-rate experiments on materials to understand how mechanical properties change with respect to the loading rate. The dynamic behavior of additively manufactured 316L stainless steel, produced by the powder bed fusion method were investigated. The effects of …

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Iimpact Of Urbanization On Precipitation From Meta-Analysis And Causal Discovery, Jie Liu May 2018

Iimpact Of Urbanization On Precipitation From Meta-Analysis And Causal Discovery, Jie Liu

Open Access Theses

Recent decades have witnessed rapid urbanization across the globe. The temperature impacts of urbanization, referred to as urban heat island, in which the cities are typically warmer than the surrounding nonurban region are well known. A growing number of studies have recently also reported an interesting dynamical feedback on the regional weather and climate asserting that cities can modify thunderstorms and affect the rainfall in and around urban areas. However, unlike the temperature effects, the impact on rainfall are still unclear. A typical feature emerging from different studies is that there is some notable modification downwind of the cities -yet …

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Can-Based Forage Yield Monitoring, Amelia M. Lindsay May 2018

Can-Based Forage Yield Monitoring, Amelia M. Lindsay

Open Access Theses

The objectives of this research were to collect and parse CAN, topography, timing, and path data for forage operations leading to individual cylindrical round bales with highest possible accuracy for subsequent analysis, to analyze fuel consumption rate and engine load data to ascertain loading differences which could reflect baler consumption rate, and to determine the possible resolution extent of forage yield maps generated without load cells or specific baler instrumentation. An ISOBlue unit (open-source telematics) was used to record CAN messages pertaining to baling of large round bales which included time, Global Positioning System (GPS) Coordinates (hence speed), fuel consumption …

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Deep Neural Network Architectures For Modulation Classification, Xiaoyu Liu May 2018

Deep Neural Network Architectures For Modulation Classification, Xiaoyu Liu

Open Access Theses

This thesis investigates the value of employing deep learning for the task of wireless signal modulation recognition. Recently in deep learning research on AMC, a framework has been introduced by generating a dataset using GNU radio that mimics the imperfections in a real wireless channel, and uses 10 different modulation types. Further, a CNN architecture was developed and shown to deliver performance that exceeds that of expert-based approaches. Here, we follow the framework of O’shea [1] and find deep neural network architectures that deliver higher accuracy than the state of the art. We tested the architecture of O’shea [1] and …

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Supporting And Amplifying Teaching Experience Of New College Teachers, Siyan Liu May 2018

Supporting And Amplifying Teaching Experience Of New College Teachers, Siyan Liu

Open Access Theses

This thesis investigates how to amplify and support novice college teacher’s teaching experience. It has been found that a majority of percent novice teachers (55%) could not prepare there are lessons effectively (Fantilli & McDougall, 2009), many of them will spend a lot of time adapting to the educating and academic environment. The main issue is that these beginning teachers cannot recognize what kinds of methods are more effective to enhance their teaching efforts in the short period term. At the meanwhile, how to enhance their class quality as a crucial problem as well. There are several factors affecting the …

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Flammability Limits Of Neat And Blended Alcohol-To-Jet Synthetic Fuels, Alex Mastrean May 2018

Flammability Limits Of Neat And Blended Alcohol-To-Jet Synthetic Fuels, Alex Mastrean

Open Access Theses

Many companies are creating innovative new aviation fuels to decrease our reliance on traditional fossil fuels and provide more environmentally friendly solutions. Before introducing these fuels as standard alternative replacements, fuel properties such as concentration and temperature limits must be evaluated to determine safe handling and fire-safety standards. This study investigates the properties of Gevo’s Alcohol-to-Jet Synthetic Paraffinic Kerosene, hereby referred to as ATJ. ATJ was also blended with Jet-A producing a 70/30 vol% Jet-A/ATJ concentration, respectively. Lower and upper concentrations limits were tested at one atmosphere and temperatures ranging from 230-350 °F. The lower concentration flammability limit fuel air …

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Language Socialization During Study Abroad: Linguistic, Communicative, And Intercultural Competencies, Taryn Sydney Mcdowell May 2018

Language Socialization During Study Abroad: Linguistic, Communicative, And Intercultural Competencies, Taryn Sydney Mcdowell

Open Access Theses

This thesis examines the process of language socialization at the dinner table between native speakers and second language learners in the homestay setting of the study abroad experience. It specifically addresses the competencies affected in the development of second language learners of Spanish through the language socialization process at the dinner table with guidance from native Spanish speakers, as well as the specific strategies employed by native speakers to increase these competencies. These competencies and strategies were investigated through the use of naturalistic data obtained via video recordings of dinnertime conversations among host families and their host students. A qualitative …

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The Acquisition Of Obligatory And Variable Subjunctive Mood Selection In Temporal And Concessive Clauses In Heritage And L2 Spanish, Eduardo Lustres May 2018

The Acquisition Of Obligatory And Variable Subjunctive Mood Selection In Temporal And Concessive Clauses In Heritage And L2 Spanish, Eduardo Lustres

Open Access Theses

The current study examines the acquisition of the obligatory and variable subjunctive mood selection in epistemic adverbial clauses by L2 learners and heritage speakers (HSs) of Spanish. The acquisition of the Spanish subjunctive shows significant variability among both L2 learners (e.g., Borgonovo, Bruhn de Garavito, & Prévost, 2008; Sánchez-Naranjo, 2009) and heritage speakers of Spanish (e.g., Potowski, Jegerski, & Morgan-Short, 2009). Several studies comparing L2 learners and heritage speakers show that heritage speakers outperform L2 learners at low and intermediate levels (e.g., Montrul & Perpiñán, 2011). Some studies claim that differences between HSs and L2 learners can be explained because …

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A Vehicle Routing Problem With Payload-Range Dependency By Fuel Consumption, Archit Chandrakant Mokashi May 2018

A Vehicle Routing Problem With Payload-Range Dependency By Fuel Consumption, Archit Chandrakant Mokashi

Open Access Theses

In this research, a new variant of vehicle routing problem is introduced. Fuel consumption constitutes a significant component of transportation costs especially when large volumes of goods are transported using means of transportation such as aircrafts. Hence, the objective of this research is to perform efficient routing of a heterogeneous fleet of vehicles such that fuel consumption costs are minimized. Reduced fuel consumption also reduces greenhouse gases emission and creates a positive impact on the environment. Another unique characteristic studied is the dependence between load carried by a vehicle and the maximum distance it can travel without stopping. Weight of …

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Effect Of Cyclic Heat Stress And Supplemented Inorganic And Organic Zinc Source Levels On Grow-Finish Pig Growth Performance, Estimated Body Composition, Intestinal Morphology And Gene Expression., Kayla Mills May 2018

Effect Of Cyclic Heat Stress And Supplemented Inorganic And Organic Zinc Source Levels On Grow-Finish Pig Growth Performance, Estimated Body Composition, Intestinal Morphology And Gene Expression., Kayla Mills

Open Access Theses

Heat stress is a physiologic state where an animal can no longer properly regulate it’s body temperature to prevent hyperthermia. It has been well documented that heat stress can negatively impact feed intake, growth performance, carcass characteristics, gut morphology and integrity in swine. Finishing swine are particularly sensitive to heat stress which costs the U.S. swine industry millions of dollars annually. There are several ways heat challenges can be mitigated to reduce the negative impacts of heat stress during warmer temperatures, one of which being nutrition. Knowing that heat stress alters intestinal barrier function and morphology, we took a holistic …

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Father Helps Best: Paternal Social Support In Television Sitcoms, Chelsea Moss May 2018

Father Helps Best: Paternal Social Support In Television Sitcoms, Chelsea Moss

Open Access Theses

The term paternal involvement is multi-faceted and includes engagement, accessibility, and responsibility (Lamb & Oppenheim, 1989). Specifically, when considering engagement, or actual time spent in interaction with children (Lamb, 2000; Lamb & Oppenheim, 1989), social support is one important consideration when understanding fathers’ influence on their children. In accordance with social role theory, individuals should expect to see television sitcom fathers behave in certain ways based on their social positions (Biddle, 1979; Eagly & Wood, 2011), potentially providing their children with various types and amounts of social support based on factors such as employment status of wife, socioeconomic status, and …

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Soil Microbial Community Dynamics During The Decomposition Period Of Winter Cover Crops, Clayton J. Nevins May 2018

Soil Microbial Community Dynamics During The Decomposition Period Of Winter Cover Crops, Clayton J. Nevins

Open Access Theses

Across the Midwest United States, there is an increasing number of agriculturalists incorporating cover crops and reduced tillage residue management into sustainable nutrient management plans. However, the impact of these treatments on the soil microbial community, and subsequently, on soil nutrient cycling and inorganic nitrogen (N) availability, is largely unknown. Therefore, this research had two objectives: i) to determine the impact of cover crop species on soil and litter enzyme activity and soil nitrogen supply during the cover crop decomposition period, and ii) to evaluate the impact of cover crops and reduced tillage on the soil microbial community diversity and …

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A Systematic Literature Review Of Project Management Tools And Their Impact On Project Management Effectiveness, Michelle Newton May 2018

A Systematic Literature Review Of Project Management Tools And Their Impact On Project Management Effectiveness, Michelle Newton

Open Access Theses

This thesis was conducted to examine project effectiveness and the best methodologies to use for managing projects as supported by the literature. Project effectiveness depends on multiple dimensions and has many situational issues that demand flexibility in method selection and utilization. Three of the most important dimensions explored in this study included: organizational structures, cost and schedule management typologies and leadership styles. A systematic literature review was utilized to collect data on the most common project management methods found to be effective according to the current literature. As projects are complex and vary greatly it was concluded from the literature …

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Good Capa Practice - A Six Sigma Approach To Reduce Cost Of Non-Compliance, Reham Osama Nour May 2018

Good Capa Practice - A Six Sigma Approach To Reduce Cost Of Non-Compliance, Reham Osama Nour

Open Access Theses

Within pharmaceutical and medical devices-based industries, there are no generalized or standardized procedures for design, implement, and control a compliance CAPA structure. Simultaneously, FDA observation reports and warning letters revealed that CAPA is still not fully understood by many of pharmaceutical/medical devices manufacturing community members. This study expands knowledge in the field of quality system regulation by offering methods and tools that work efficiently within the CAPA structure. while, at the same time, sustaining productivity through critical evaluation of FDA warning letters which considered a great tool for professionals and researchers. This provide a great insight on how to build …

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“I’M Helping To Put A Man On The Moon”: Communicating Higher Purpose In The Workplace, Kristen Michele Olson May 2018

“I’M Helping To Put A Man On The Moon”: Communicating Higher Purpose In The Workplace, Kristen Michele Olson

Open Access Theses

Higher purpose in one’s work can be defined as a driving force that extends beyond oneself that fulfills some larger need, goal, or hope and perhaps benefits others. This construct may have important implications for workplace motivation and engagement. A survey by Calling Brands (2012) found that 65% of workers would put in more effort for an organization with a higher purpose. Furthermore, a joint study by Net Impact and Rutgers University found that for 24% of the workforce and 45% of college students, “a job that seeks to make a social or environmental difference in” (Zukin & Szeltner, 2012, …

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Effect Of Starch-Based Hydrogel On Early Growth Of Corn, Vaibhav Pathak May 2018

Effect Of Starch-Based Hydrogel On Early Growth Of Corn, Vaibhav Pathak

Open Access Theses

Seed coating with highly absorbent polymers can potentially improve the water availability for early growth of seeds under dry conditions and therefore prevent associated delays in the emergence and reduced crop stand. The limited number of studies on hydrogel seed coatings have shown that their effect on seed growth is not always beneficial, and varies with plant species, amount of hydrogel used and amount of available water in the growing medium. The current work studied the effect of hydrogel seed coating on the early growth of corn using starch-based biodegradable hydrogels. The hydrogels were prepared from potato starch (PS) and …

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Feature Learning As A Tool To Identify Existence Of Multiple Biological Patterns, Aleksandr Patsekin May 2018

Feature Learning As A Tool To Identify Existence Of Multiple Biological Patterns, Aleksandr Patsekin

Open Access Theses

This paper introduces a novel approach for assessing multiple patterns in biological imaging datasets. The developed tool should be able to provide most probable structure of a dataset of images that consists of biological patterns not encountered during the model training process. The tool includes two major parts: (1) feature learning and extraction pipeline and (2) subsequent clustering with estimation of number of classes. The feature-learning part includes two deep-learning techniques and a feature quantitation pipeline as a benchmark method. Clustering includes three non-parametric methods. K-means clustering is employed for validation and hypothesis testing by comparing results with provided ground …

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