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Articles 571 - 600 of 3436

Full-Text Articles in Physical Sciences and Mathematics

A Developer Usability Study Of Tls Libraries, Jonathan Blake Armknecht Sep 2020

A Developer Usability Study Of Tls Libraries, Jonathan Blake Armknecht

Theses and Dissertations

Transport Layer Security (TLS) is a secure communication protocol between a client and a server over a network. The TLS protocol provides the two endpoints with confidentiality through symmetric encryption, endpoint authentication using public-key cryptography, and data integrity using a MAC. However, studies show that security vulnerabilities within TLS connections are often caused by developers misusing TLS library APIs. We measure the usability of four TLS libraries by performing a developer user study. Participants were given code that connects to google.com through HTTP, and tasked with using a TLS library to change the code so that it connects securely to …

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Ansible: Select-To-Edit For Physical Widgets, Benjamin M. Crowder Sep 2020

Ansible: Select-To-Edit For Physical Widgets, Benjamin M. Crowder

Theses and Dissertations

Ansible brings select-to-edit functionality to physical widgets. When programming sets of physical widgets, it can be bothersome for a programmer to remember the name of the software object that corresponds to a specific widget. Click-to-edit functionality in GUI programming provides a physical action--moving the mouse to a widget and clicking a button on the mouse--to select a virtual widget. In a similar vein, when programming physical widgets, it is natural to point at a widget and think, "I want to program that one." Ansible allows physical user interface programmers to "click" on a physical widget by making a physical action: …

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Physical Characterization Of Crackle-Related Events In Military Jet Aircraft Noise, Aaron Burton Vaughn Aug 2020

Physical Characterization Of Crackle-Related Events In Military Jet Aircraft Noise, Aaron Burton Vaughn

Theses and Dissertations

Crackle is a perceptual feature of supersonic jet noise that is related to the presence of acoustic shocks. The skewness of the time-derivative of the pressure waveform, or derivative skewness, is used as a metric indicative of crackle perception. The three main objectives of this work are: 1) Determine the potential spatial origin of crackle-related events in the near field of a high-performance military aircraft via an event-based beamforming method. 2) Investigate the potential for nonlinear, irregular shock reflections occurring along the near-field ground array and their implications on derivative skewness. 3) Relate the near-field, crackle-related events to far-field crackle …

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Angular Dependence Of Nonlinear Thomson Scattering From Electrons In A High Intensity Laser Focus, Christoph Alexander Schulzke Aug 2020

Angular Dependence Of Nonlinear Thomson Scattering From Electrons In A High Intensity Laser Focus, Christoph Alexander Schulzke

Theses and Dissertations

The theory of nonlinear Thomson scattering is presented. A model for the scattered light is developed. The orthogonal polarizations of the second harmonic of the scattered light are examined. The predictions of the model are compared to measurements by our group in collaboration with the Extreme Light Laboratory at the University of Nebraska-Lincoln (UNL). The veracity of the theory and model are confirmed by comparison to the experimental data.

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Deep Learning To Predict Ocean Seabed Type And Source Parameters, David Franklin Van Komen Aug 2020

Deep Learning To Predict Ocean Seabed Type And Source Parameters, David Franklin Van Komen

Theses and Dissertations

In the ocean, light from the surface dissipates quickly leaving sound the only way to see at a distance. Different sediment types on the ocean floor and water properties like salinity, temperature, and ocean depth all change how sound travels across long distances. Hard sediment types, such as sand and bedrock, are highly reflective while softer sediment types, such as mud, are more absorptive and change the received sound upon arrival. Unfortunately, the vast majority of the ocean floor is not mapped and the expenses involved in creating such a map are far too great. Traditional signal processing methods in …

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Polarization Of Nonlinear Thomson Scattering From A High Intensity Laser Focus, Brittni Tasha Pratt Aug 2020

Polarization Of Nonlinear Thomson Scattering From A High Intensity Laser Focus, Brittni Tasha Pratt

Theses and Dissertations

Thomson scattering from free electrons in a high-intensity laser focus has been widely studied analytically, but not many measurements of this scattering have been made. We measure polarization-resolved nonlinear Thomson scattering from electrons in a high-intensity laser focus using a parabolic mirror. The weak scattering signal is distinguished from background noise using single-photon detectors and nanosecond time-resolution to distinguish a prompt scattering signal from noise photons. The azimuthal and longitudinal components of the fundamental, second, and third harmonics were measured. Our measurements reasonably match theoretical results, but also show some asymmetry in the emission patterns.

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Secondary Mathematics Teachers' Mindsets, Emily Ann Hales Kunz Aug 2020

Secondary Mathematics Teachers' Mindsets, Emily Ann Hales Kunz

Theses and Dissertations

Much research supports that student mindset influences how well students do in school and that teacher actions influence student mindset. Research has also shown that just because a teacher has a growth mindset, it does not imply that their students will also have a growth mindset. This research looks closer as to why a teacher's mindset does not correlate with their students' mindset by further examining teacher mindset and the connection between teacher mindset and teacher actions. In summary, teachers' mindsets do not directly influence student mindset for a few reasons: secondary mathematics teachers have different mindsets towards honors and …

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Structure Of Collisional Metamorphism, Soft-Sediment Deformation, And Low-Angle Normal Faulting In The Beaver Dam Mountains, Jacob Isaac Voorhees Aug 2020

Structure Of Collisional Metamorphism, Soft-Sediment Deformation, And Low-Angle Normal Faulting In The Beaver Dam Mountains, Jacob Isaac Voorhees

Theses and Dissertations

Precambrian metamorphic rocks in the Beaver Dam Mountains display asymmetric, isoclinal folds with consistent fold axes plunging to the NW. These folds are parasitic and have a recursive nature that occurs on wavelengths from centimeters to perhaps kilometers as part of a NW-SE striking shear zone. The vergence of the folds indicates oblique shearing with a transport direction plunging 29° to the south. This shear zone may be associated with the collision of Yavapai Province island arcs with Laurentia. Structurally overlying, and adjacent to the metamorphic rocks are allochthonous and attenuated Mississippian limestone blocks and other strata debated to be …

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Dynamics Of Interal Phosporus Cycling In A Highly Eutrophic, Shallow, Fresh Water Lake In Utah Lake State Park, Utah, Usa, Sheena Marie Smithson Aug 2020

Dynamics Of Interal Phosporus Cycling In A Highly Eutrophic, Shallow, Fresh Water Lake In Utah Lake State Park, Utah, Usa, Sheena Marie Smithson

Theses and Dissertations

Eutrophication is an increasing global concern as human effluent saturates lakes with an over abundance of nutrients. Phosphorus, generally being the limiting nutrient, is often the most impactful, allowing cyanobacteria populations to grow out of control leading to harmful blooms that can produce cyanotoxins, anoxic lake conditions, and mass fish kills. Utah Lake, a shallow highly eutrophic fresh water lake located in central Utah Valley, has experienced these harmful algal blooms for the last several years. The internal phosphorus cycle is a significant driver in Utah Lake's eutrophication, as the sediments act as both a sink and a source for …

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Internships Shape Students' Future Career, Maria F. Arrayan Aug 2020

Internships Shape Students' Future Career, Maria F. Arrayan

Marriott Student Review

Finding an internship has been more difficult than before due to COVID-19. For many, the search for an internship may be frustrating or pointless during this difficult time. Students need to empower themselves with the right tools to find an internship. Maria Fernanda Arrayan talks about the benefits of an internship and four ways to find one. Read this article to find motivation in your search for an internship and try a new way to find your next internship!

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Synthesis Of Bacterial Surface Glycans For Conjugate Vaccines, Teron D. Haynie Aug 2020

Synthesis Of Bacterial Surface Glycans For Conjugate Vaccines, Teron D. Haynie

Theses and Dissertations

Bacteria are coated with repeating units of oligosaccharides that exhibit remarkable diversity. Often, glycan units of three or even two sugars are sufficient to identify a species of bacteria. Such specificity makes bacterial surface glycans attractive vaccine targets. However, efforts to create effective vaccines against carbohydrates have been hampered by poor vaccine design as well as the human immune tendency to respond to glycan antigens with non-specific, T-cell independent mechanisms. As a result, carbohydrate vaccines have historically produced only adequate memory responses in healthy individuals and poor responses in the elderly or immunocompromised. To circumvent these issues, a novel conjugate …

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Building An Ins-1 Cdna Library For A Genome-Wide Crispr-Cas9 Screen, Idongesit Ekpo Aug 2020

Building An Ins-1 Cdna Library For A Genome-Wide Crispr-Cas9 Screen, Idongesit Ekpo

Undergraduate Honors Theses

By the year 2040, an estimated 642 million people are expected to have diabetes globally. Diabetes results from an elevation of metabolic stressors, such as glucotoxicity, lipotoxicity, oxidative stress and apoptosis. In type 2 diabetes, these stressful conditions contribute to the malfunction and loss of functional insulin-producing β-cells. Current treatment methods for diabetes include insulin therapy, islet transplant and anti-diabetes medication. These treatments are not curative and ignore other factors that contribute to the pathogenesis of diabetes beyond insulin resistance and islet β-cell failure. Previous research on β-cells has focused on ways to replace functional β-cell mass, trigger β-cell proliferation, …

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A Method For Reconstructing Historical Destructive Earthquakes Using Bayesian Inference, Hayden J. Ringer Aug 2020

A Method For Reconstructing Historical Destructive Earthquakes Using Bayesian Inference, Hayden J. Ringer

Theses and Dissertations

Seismic hazard analysis is concerned with estimating risk to human populations due to earthquakes and the other natural disasters that they cause. In many parts of the world, earthquake-generated tsunamis are especially dangerous. Assessing the risk for seismic disasters relies on historical data that indicate which fault zones are capable of supporting significant earthquakes. Due to the nature of geologic time scales, the era of seismological data collection with modern instruments has captured only a part of the Earth's seismic hot zones. However, non-instrumental records, such as anecdotal accounts in newspapers, personal journals, or oral tradition, provide limited information on …

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Breaking The Organic Mold: Introducing Copper Into The Influenza A Arena With Neutral And Divalent Complexes, Jonathan D. Lynch Aug 2020

Breaking The Organic Mold: Introducing Copper Into The Influenza A Arena With Neutral And Divalent Complexes, Jonathan D. Lynch

Theses and Dissertations

Influenza A (IVA) continues to pose a growing global threat even as current medications are becoming less effective. One of the main avenues of research into new anti-IVA drugs is its homotetrameric Matrix 2 proton channel (M2A), without which the virus would be unable to release its viral RNA into the host cell. The drug amantadine used to bind and block M2A until near-ubiquitous resistance formed as an M2A-S31N mutation, starting around 1995 and proceeding to 2005 when amantadine was disallowed for use as an anti-IVA drug. The standard organic structure currently being used for M2A inhibitor research comprises an …

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Discovery Of A Novel Regulatory Mechanism Of Tnk1 By 14-3-3 And Its Ubiquitin Association Domain Provides A Potential Therapeutic Targeting Opportunity In Cancer, Tsz Yin Chan Aug 2020

Discovery Of A Novel Regulatory Mechanism Of Tnk1 By 14-3-3 And Its Ubiquitin Association Domain Provides A Potential Therapeutic Targeting Opportunity In Cancer, Tsz Yin Chan

Theses and Dissertations

While a relatively limited number of known oncogenes underlie a large percentage of cancers, a variety of new genes have emerged as low-frequency cancer drivers. Each of these new oncogenes represents a frontier for targeted therapy. However, the discovery of low-frequency targetable oncogenic drivers is challenging. This study focuses on the poorly understood Tyrosine kinase non-receptor-1 (TNK1), which has been reported to have both oncogenic and tumor suppressive functions. TNK1 has been identified to promote cancer cells survival and promote chemoresistance in multiple independent studies. On the other hand, whole-body constitutive deletion of TNK1 in mice caused an increase in …

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Zipperotf: Automatic, Precise, And Simple Data Race Detection For Task Parallel Programs With Mutual Exclusion, S. Jacob Powell Jul 2020

Zipperotf: Automatic, Precise, And Simple Data Race Detection For Task Parallel Programs With Mutual Exclusion, S. Jacob Powell

Theses and Dissertations

Data race in parallel programs can be difficult to precisely detect, and doing so manually can often prove unsuccessful. Task parallel programming models can help reduce defects introduced by the programmer by restricting concurrent functionalities to fork-join operations. Typical data race detection algorithms compute the happens-before relation either by tracking the order that shared accesses happen via a vector clock counter, or by grouping events into sets that help classify which heap locations are accessed sequentially or in parallel. Access sets are simple and efficient to compute, and have been shown to have the potential to outperform vector clock approaches …

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Clarque: Chatbot Recognizing Ambiguity In The Conversation And Asking Clarifying Questions, Shreeya Himanshu Mody Jul 2020

Clarque: Chatbot Recognizing Ambiguity In The Conversation And Asking Clarifying Questions, Shreeya Himanshu Mody

Theses and Dissertations

Recognizing when we need more information and asking clarifying questions are integral to communication in our day to day life. It helps us complete our mental model of the world and eliminate confusion. Chatbots need this technique to meaningfully collaborate with humans. We have investigated a process to generate an automated system that mimics human communication behavior using knowledge graphs, weights, an ambiguity test, and a response generator. It can take input dialog text and based on the chatbot's knowledge about the world and the user it can decide if it has enough information or if it requires more. Based …

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Age-Suitability Prediction For Literature Using Deep Neural Networks, Eric Robert Brewer Jul 2020

Age-Suitability Prediction For Literature Using Deep Neural Networks, Eric Robert Brewer

Theses and Dissertations

Digital media holds a strong presence in society today. Providers of digital media may choose to obtain a content rating for a given media item by submitting that item to a content rating authority. That authority will then issue a content rating that denotes to which age groups that media item is appropriate. Content rating authorities serve publishers in many countries for different forms of media such as television, music, video games, and mobile applications. Content ratings allow consumers to quickly determine whether or not a given media item is suitable to their age or preference. Literature, on the other …

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Optimal Learning Rates For Neural Networks, Tyler Moncur Jul 2020

Optimal Learning Rates For Neural Networks, Tyler Moncur

Theses and Dissertations

Neural networks have long been known as universal function approximators and have more recently been shown to be powerful and versatile in practice. But it can be extremely challenging to find the right set of parameters and hyperparameters. Model training is both expensive and difficult due to the large number of parameters and sensitivity to hyperparameters such as learning rate and architecture. Hyperparameter searches are notorious for requiring tremendous amounts of processing power and human resources. This thesis provides an analytic approach to estimating the optimal value of one of the key hyperparameters in neural networks, the learning rate. Where …

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Applications Of Mathematical Optimization Methods To Digital Communications And Signal Processing, Spencer Giddens Jul 2020

Applications Of Mathematical Optimization Methods To Digital Communications And Signal Processing, Spencer Giddens

Theses and Dissertations

Mathematical optimization is applicable to nearly every scientific discipline. This thesis specifically focuses on optimization applications to digital communications and signal processing. Within the digital communications framework, the channel encoder attempts to encode a message from a source (the sender) in such a way that the channel decoder can utilize the encoding to correct errors in the message caused by the transmission over the channel. Low-density parity-check (LDPC) codes are an especially popular code for this purpose. Following the channel encoder in the digital communications framework, the modulator converts the encoded message bits to a physical waveform, which is sent …

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Teachers' Mathematical Meanings: Decisions For Teaching Geometric Reflections And Orientation Of Figures, Porter Peterson Nielsen Jul 2020

Teachers' Mathematical Meanings: Decisions For Teaching Geometric Reflections And Orientation Of Figures, Porter Peterson Nielsen

Theses and Dissertations

Teachers' instructional decisions are important for students' mathematics learning as they determine the learning opportunities for all students. This study examines teachers' decisions about the activities and tasks they choose for students' mathematics learning, the ordering and connecting of mathematics topics, and the mathematics within curricula not to cover. These decisions are referred to as curricular decisions. I also identify teachers' mathematical schemes, referred to as mathematical meanings, in relation to geometric reflections and orientation of figures and examine teachers' reasoning with their mathematical meanings as they make these curricular decisions. Additionally, based on the results of this study I …

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Facing The Hard Problems In Fgvc, Connor Stanley Anderson Jul 2020

Facing The Hard Problems In Fgvc, Connor Stanley Anderson

Theses and Dissertations

In fine-grained visual categorization (FGVC), there is a near-singular focus in pursuit of attaining state-of-the-art (SOTA) accuracy. This work carefully analyzes the performance of recent SOTA methods, quantitatively, but more importantly, qualitatively. We show that these models universally struggle with certain "hard" images, while also making complementary mistakes. We underscore the importance of such analysis, and demonstrate that combining complementary models can improve accuracy on the popular CUB-200 dataset by over 5%. In addition to detailed analysis and characterization of the errors made by these SOTA methods, we provide a clear set of recommended directions for future FGVC researchers.

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Implications Of Geochemistry And Textures Of Titanite For The Geologic Histories Of The Notch Peak Intrusion And Little Cottonwood Stock, Utah, Porter Henze Jul 2020

Implications Of Geochemistry And Textures Of Titanite For The Geologic Histories Of The Notch Peak Intrusion And Little Cottonwood Stock, Utah, Porter Henze

Theses and Dissertations

Textural and compositional variations in titanite, along with whole-rock geochemistry, provide constraints on the emplacement and cooling histories of two plutons: the Jurassic Notch Peak pluton and the Oligocene Little Cottonwood stock, both in Utah. Titanite textures observed with back-scattered electron (BSE) imaging along with their compositions were used to determine four periods of growth: cores, rims, interstitial overgrowths, and secondary replacements. Brightness in BSE images correlates mostly with rare earth elements (REE). REE patterns in cores and rims are compositionally similar in both plutons, although the Notch Peak intrusion tend to be slightly more enriched in REE. Overgrowths and …

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Specialization: Do Your Job Well Helping Students Who Are Considering A Career In Programming Know How To Invest Their Time., Scott Pulley Jul 2020

Specialization: Do Your Job Well Helping Students Who Are Considering A Career In Programming Know How To Invest Their Time., Scott Pulley

Marriott Student Review

The article examines the effects of specialization on the hiring process for undergraduates studying programming whether in information systems or computer science.

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The Role Of The Chaperone Cct In Assembling Cell Signaling Complexes, Nicole C. Tensmeyer Jul 2020

The Role Of The Chaperone Cct In Assembling Cell Signaling Complexes, Nicole C. Tensmeyer

Theses and Dissertations

In order to function, proteins must be folded into their native shape. While this can sometimes occur spontaneously, the process can be hindered by thermodynamic barriers, trapped intermediates, and aggregation prone hydrophobic interactions. Molecular chaperones are proteins that help client proteins or substrates overcome these barriers so that they can be folded properly. One such chaperone is the chaperonin CCT, a large MDa protein made up of 16 paralogous subunits that form a double ring structure. CCT encapsulates its substrates in a central cavity, where they are sequestered and folded, using ATP binding and hydrolysis to drive conformational changes in …

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Links Between Eruptive Styles, Magmatic Evolution, And Morphology Of Low-Shield Volcanoes: Snake River Plain, Idaho, Katelyn J. Barton Jul 2020

Links Between Eruptive Styles, Magmatic Evolution, And Morphology Of Low-Shield Volcanoes: Snake River Plain, Idaho, Katelyn J. Barton

Theses and Dissertations

In this study, connections between chemical composition, eruption style, and topographic features of two shield volcanoes on the Snake River Plain, Idaho are examined. These relationships may then be applied to understanding silicate volcanic features throughout the inner solar system. Despite their similar ages and geographic locations, two young basaltic shield volcanoes—Kimama Butte (87 Ka) and Rocky Butte (95 Ka)—have strikingly different topographic profiles. The Kimama Butte shield has a diameter of 9 km and a height of 210 m. In contrast, Rocky Butte has a broad 36 km topographic shield that rises 140 m with less than 1° slopes. …

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Vulnerability Analysis Of Infrastructure Systems, Sean Theodore Lane Jul 2020

Vulnerability Analysis Of Infrastructure Systems, Sean Theodore Lane

Theses and Dissertations

Complex cyber-physical systems have become fundamental to modern society by effectively providing critical services and improving efficiency in various domains. Unfortunately, as systems become more connected and more complex, they also can become more vulnerable and less robust. As a result, various failure modes become more common and easily triggered from both unanticipated and malicious perturbations. Research has been conducted in the area of vulnerability analysis for cyber-physical systems, to assist in locating these possible vulnerabilities before they can fail. I present two case studies on different forms of critical infrastructure systems to identify vulnerabilities and understand how external perturbations …

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High Order Numerical Methods For Problems In Wave Scattering, Dane Scott Grundvig Jun 2020

High Order Numerical Methods For Problems In Wave Scattering, Dane Scott Grundvig

Theses and Dissertations

Arbitrary high order numerical methods for time-harmonic acoustic scattering problems originally defined on unbounded domains are constructed. This is done by coupling recently developed high order local absorbing boundary conditions (ABCs) with finite difference methods for the Helmholtz equation. These ABCs are based on exact representations of the outgoing waves by means of farfield expansions. The finite difference methods, which are constructed from a deferred-correction (DC) technique, approximate the Helmholtz equation and the ABCs to any desired order. As a result, high order numerical methods with an overall order of convergence equal to the order of the DC schemes are …

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Information Geometry And Model Reduction In Oscillatory And Networked Systems, Benjamin Lane Francis Jun 2020

Information Geometry And Model Reduction In Oscillatory And Networked Systems, Benjamin Lane Francis

Theses and Dissertations

In this dissertation, I consider the problem of model reduction in both oscillatory and networked systems. Previously, the Manifold Boundary Approximation Method (MBAM) has been demonstrated as a data-driven tool for reducing the parametric complexity of so-called sloppy models. To be effective, MBAM requires the model manifold to have low curvature. I show that oscillatory models are characterized by model manifolds with high curvature in one or more directions. I propose methods for transforming the model manifolds of these models into ones with low curvature and demonstrate on a couple of test systems. I demonstrate MBAM as a tool for …

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Multi-Objective Intent-Based Path Planning For Robots For Static And Dynamic Environments, Meher Talat Shaikh Jun 2020

Multi-Objective Intent-Based Path Planning For Robots For Static And Dynamic Environments, Meher Talat Shaikh

Theses and Dissertations

This dissertation models human intent for a robot navigation task, managed by a human and undertaken by a robot in a dynamic, multi-objective environment. Intent is expressed by a human through a user interface and then translated into a robot trajectory that satisfies a set of human-specified objectives and constraints. For a goal-based robot navigation task in a dynamic environment, intent includes expectations about a path in terms of objectives and constraints to be met. If the planned path drifts from the human's intent as the environment changes, a new path needs to be planned. The intent framework has four …

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