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Social Groups Characterization And Dynamics: A Network Science Approach, Josemar Faustino Da Cruz
Social Groups Characterization And Dynamics: A Network Science Approach, Josemar Faustino Da Cruz
Theses and Dissertations
Over the course of our lives, we tend to transition through many social groups. From an early age, our first social group is our family, then we have our schoolmates, later in life, our coworkers, and likely another family. As we move from one group to another, we embed ourselves in the dynamics of social groups’ losses and gains of new members. These dynamics are a complex system of interactions, which at scale, form the structural basis of our societies. In many years of sociological research, the details of social group interactions remained poorly understood. Certainly, not because of lack …
Building Datasets From Publicly Accessible Social Media Images For Biometric Analysis, Giordano Roberto Benitez Torres
Building Datasets From Publicly Accessible Social Media Images For Biometric Analysis, Giordano Roberto Benitez Torres
Theses and Dissertations
The world is developing at a rapid pace, and some of its advancement can be accredited to technological innovations that are affecting many aspects of society. A field within computer science that is increasingly reaching many industries is Biometrics, specifically the area face recognition. Researchers, scientists, and organizations actively try to improve the performance of tools and algorithms. Nevertheless, for it to occur, there is a need for high-quality datasets to test and develop new techniques. Never had humanity, in the course of the history of civilization, produced massive amounts of data as it currently does. Social media networks play …
A Compositional Analysis Of Artificial And Terrestrial Analog Martian Regolith Simulants, Beverly Watson Kemmerer
A Compositional Analysis Of Artificial And Terrestrial Analog Martian Regolith Simulants, Beverly Watson Kemmerer
Theses and Dissertations
Over the past 50 years, significant advances in the knowledge of the topography, climate, and geology of Mars have taken place. The global Martian regolith composition is highly basaltic, primarily composed of pyroxene, plagioclase, and olivine, a mixture of Fe oxides and Fe-Ti oxides, and some alteration minerals, i.e. sulfates, carbonates, and clays. The particle size distribution of Martian regolith ranges from 1 µm to 1000 µm, with average Martian soil grain sizes being 250 µm to 300 µm. These regolith properties, as well as geotechnical properties, all play a part in the outcome of certain in situ resource utilization …
A Taxonomy Of Security Features For The Comparison Of Home Automation Protocols, Amal Abdullah Alasiri
A Taxonomy Of Security Features For The Comparison Of Home Automation Protocols, Amal Abdullah Alasiri
Theses and Dissertations
Both academia and industry environments are getting significant attention to the Internet-of-Things (IoT) technology because of the unlimited benefits that this technology can bring to the environment. The technology presents a vision of a future Internet where computing systems, nodes, users, and daily nodes such as sensors and actuators cooperate with unprecedented convenience and economic benefits. The umbrella of IoT covers various applications as the following (smart home, transport, community, and national applications). Most of the studies focus on its technical and usage more than the security perspective. Especially, there are limited papers focus on smart home protocols security regarding …
Human-Robot Plan Communication, Rajaa A. Rahil
Human-Robot Plan Communication, Rajaa A. Rahil
Theses and Dissertations
Although the technical development of robots has made them more autonomous, they still benefit from some human skills and advice. Therefore, the robot needs to interact with a human and ask him for help to get out of difficulties in the best way. This dissertation addresses the problem of finding better mechanisms to communicate to a robot the directions for navigation in indoor environments. We identify which out of a set of combinations of speech, gestures, and drawing mechanisms are the most comfortable, easier to learn, and least error-prone for human users. Three different methods: a Speaking method, a Gesturing …
An Estimation Of Light Attenuation In A Shallow Estuary Using In-Situ Observations And Multispectral Satellite Imagery, Samin Taosif Aziz
An Estimation Of Light Attenuation In A Shallow Estuary Using In-Situ Observations And Multispectral Satellite Imagery, Samin Taosif Aziz
Theses and Dissertations
A methodology is used to predict the underwater light field using data from the WorldView-3 (WV-3) multispectral satellite sensor. WV-3 multispectral imagery is analyzed to estimate reflectance above the water surface, followed by application of empirical algorithms at different water depth locations to estimate light attenuation and penetration depths in shallow water. This approach uses (a) full bit resolution WV-3 imagery, (b) top of atmosphere spectral radiance to estimate reflectance at the sensor and (c) atmospheric corrections to estimate water surface reflectance just above the water. After the water reflectance is obtained, it is used to correct for water surface …
Measurements And Synthetic Imaging Of Water Surface Gravity Waves Using Optical Techniques, Jennifer Closson
Measurements And Synthetic Imaging Of Water Surface Gravity Waves Using Optical Techniques, Jennifer Closson
Theses and Dissertations
Remote sensing technologies are useful tools when gathering spatial and temporal information about dynamic coastal regions. A method is proposed using an in-situ space-time imaging technique for evaluating wave periods and wavelengths of surface water waves in shallow urban coastal water environments. Video imagery of shallow water waves was acquired using high definition video cameras. Video imagery records of surface water waves using staff gauges and simultaneously deployed targets were used to determine wave periods, wavelengths and wave amplitudes. Time series analyses is applied to the video derived time series. Wave energy spectrums are extracted and used to simulated synthetic …
Machine Learning Models On Prognostic Outcome Prediction For Cancer Images With Multiple Modalities, Gengbo Liu
Machine Learning Models On Prognostic Outcome Prediction For Cancer Images With Multiple Modalities, Gengbo Liu
Theses and Dissertations
Machine learning algorithms have been applied to predict different prognostic outcomes for many different diseases by directly using medical images. However, the higher resolution in various types of medical imaging modalities and new imaging feature extraction framework brings new challenges for predicting prognostic outcomes. Compared to traditional radiology practice, which is only based on visual interpretation and simple quantitative measurements, medical imaging features can dig deeper within medical images and potentially provide further objective support for clinical decisions. In this dissertation, we cover three projects with applying or designing machine learning models on predicting prognostic outcomes using various types of …
Analysis Of Interfaces For The Nonlinear Degenerate Second Order Parabolic Equations Modeling Diffusion-Convection Processes, Lamees Kadhim Ali Alzaki
Analysis Of Interfaces For The Nonlinear Degenerate Second Order Parabolic Equations Modeling Diffusion-Convection Processes, Lamees Kadhim Ali Alzaki
Theses and Dissertations
Dissertation pursues analysis of the short-time evolution of interfaces or free boundaries for the non-negative solutions of the nonlinear degenerate second order parabolic partial differential equation (PDE) ut = ( u m ) xx +b ( u γ ) x , x ∈ R,t > 0; m > 1, γ > 0,b ∈ R (1) modeling diffusion-convection processes arising in fluid or gas flow in a porous media, plasma physics, population dynamics in mathematical biology and other applications. Due to the implicit degeneration (m > 1), PDE (1) it possesses a property of the finite speed of propagation and develops interfaces or free boundaries …
Stability Analysis Of Neutral Functional Differential Equations Arising In Partial Element Equivalent Circuit Models, Howard Michael Allison
Stability Analysis Of Neutral Functional Differential Equations Arising In Partial Element Equivalent Circuit Models, Howard Michael Allison
Theses and Dissertations
Neutral Functional Differential Equations (NFDEs) arise in the study of the Partial Element Equivalent Circuit (PEEC) model with time delays. We present sufficient conditions for asymptotic stability and global stability in the delays of the PEEC NFDE’s, using Lyapunov-Razumikhin function methods.. We develop, for the first time, a standard mixing-type nonlinearity for the PEEC NFDEs. Introducing time invariant and time varying nonlinear perturbation to the PEEC NFDEs, we develop sufficient conditions for stability of the nonlinear perturbed PEEC NFDEs and convergence of the nonlinear system to the original stable linear autonomous system. We also develop sufficient conditions for stability and …
Some Free Boundary Problems For The Nonlinear Degenerate Multidimensional Parabolic Equations Modeling Reaction-Diffusion Processes, Amna Abu Weden
Some Free Boundary Problems For The Nonlinear Degenerate Multidimensional Parabolic Equations Modeling Reaction-Diffusion Processes, Amna Abu Weden
Theses and Dissertations
This dissertation presents a full classification of the short-time behavior of the interfaces or free boundaries for the nonlinear second order degenerate multidimensional parabolic partial differential equation (PDE) ut −∆u m +buβ = 0, x ∈ R N ,0 < t < T (1) with m > 0, β > 0,b ∈ R, arising in various applications in fluid mechanics, filtration of oil or gas in a porous media, plasma physics, reaction-diffusion equations in chemical kinetics, population dynamics in mathematical biology etc. as a mathematical model of nonlinear diffusion phenomena in the presence of the absorption or release of energy. Cauchy problem with compactly supported and nonnegative initial function …
An Agile And Rapidly Reconfigurable Test Bed For Hardware-Based Security Features, Daniel Smith Beard
An Agile And Rapidly Reconfigurable Test Bed For Hardware-Based Security Features, Daniel Smith Beard
Theses and Dissertations
Current general-purpose computing hardware and the software that runs on it have evolved over more than a half century from large mainframe systems in corporate, military, and research use to interconnected commodity devices more common than wrist watches. Computational power, storage capacity, and communication capabilities have increased in wonderful and staggering ways; however, when we read about the latest vulnerability or data breach it seems that cybersecurity is stuck somewhere between 1983 when Matthew Broderick first heard a synthesized voice ask “Shall we play a game?”, [93] and 1988 when the Morris worm hit the Internet [116]. Multics [82] and …
Computational Models For Biological Locomotion In Gels, Hashim Mohammed Alshehri
Computational Models For Biological Locomotion In Gels, Hashim Mohammed Alshehri
Theses and Dissertations
We investigated Low Reynold’s Number Locomotion in two-phase biological gels. The gel is composed of two materials: a viscous fluid solvent phase and a viscoelastic polymer network phase. A novel Two-phase Immersed Boundary Method (IBM) is developed to simulate the complicated interactions between an elastic boundary and a mixture of two fluids with very different physical properties. A further extension of the method is developed for the case where fluids satisfy partial-slip and free-slip conditions on the elastic boundary. Our major conclusions are summarized as following: (i) Our numerical scheme is proved to be robust and efficient. It can successfully …
Gut Content Analysis Of Benthic Foraging Fish Compared To Invertebrate Infauna Distributions In Dredged Vs. Undredged Habitats, Danielle Louise Juzwick
Gut Content Analysis Of Benthic Foraging Fish Compared To Invertebrate Infauna Distributions In Dredged Vs. Undredged Habitats, Danielle Louise Juzwick
Theses and Dissertations
The Indian River Lagoon (IRL) has experienced a loss in seagrasses due to organic sediment accumulation and harmful algal blooms. Seagrasses are an essential nursery habitat for many fishes and benthic invertebrates. IRL fish known to utilize benthic habitat and feed on invertebrates include Atlantic croaker (Micropogonias undulates), juvenile Red Drum (Sciaenops ocellatus), and Mojarra (Eucinostomus spp.). The most abundant major infaunal taxa of the IRL are crustaceans, polychaetes, and mollusks. Environmental dredging in the IRL’s Turkey Creek is intended to improve water quality, remove harmful sediments and restore benthic habitat. Such dredging may impact benthic invertebrate populations and, indirectly, …
Applying Formal Methods For Integrating Advanced Algorithms In Safety Critical Systems, Milton Stafford
Applying Formal Methods For Integrating Advanced Algorithms In Safety Critical Systems, Milton Stafford
Theses and Dissertations
In software engineering it is essential that updates are deployed for continual improvement. While software updates bring new functionality, updates also may introduce instability. This leads to failures of various kinds. This is especially problematic in safety-critical systems where there is a potential for injury or loss of life. However, newer and more sophisticated software carries potential advantages, including higher performance and reliability. Therefore, there are benefits in adopting newer software if the integration process is assured. In this thesis, I present a framework for assured integration; one that links requirements, design, and implementation. The proposed framework includes a new …
Improving The Classification Of Tiny Images For Forensic Analysis, Roba Jafar Alharbi
Improving The Classification Of Tiny Images For Forensic Analysis, Roba Jafar Alharbi
Theses and Dissertations
Forensics can be defined as the approach that connects with and uses in governments and different organizations in order to detect any malicious activity. Digital forensics has become an essential approach to cyber investigation. Image forensics is one of the most beneficial ways that are used in digital forensics in order to help investigators in cybercrimes. Therefore, investigators can discover some new evidence besides what is already available on their systems when they use some digital forensics techniques. This thesis focuses on identifying an image based on its contents, especially tiny images. We investigated ways to improve the performance of …
Nonlocal Boundary Value Problems For Linear Hyperbolic Systems With Two Independent Variables, Afrah Almutairi
Nonlocal Boundary Value Problems For Linear Hyperbolic Systems With Two Independent Variables, Afrah Almutairi
Theses and Dissertations
Nonlocal boundary value problems in a characteristic rectangle for second order linear hyperbolic systems are considered. There are established: (i) Unimprovable sufficient conditions for general boundary value problems to possess the Fredholm property; (ii) Optimal sufficient conditions of unique solvability of general boundary value problems; (iii) Effective sufficient conditions for doubly periodic problems to possess the Fredholm property; (iv) Unimprovable sufficient conditions of unique solvability of doubly periodic problems; (v) Effective sufficient conditions for boundary value problems of periodic type to possess the Fredholm property; (vi) Unimprovable sufficient conditions of unique solvability of boundary value problems of periodic type; (vii) …
Metastable-State Photoacids And Polymers With High Photoacidity, Thaaer Khalil
Metastable-State Photoacids And Polymers With High Photoacidity, Thaaer Khalil
Theses and Dissertations
In recent years, metastable-state photoacids (mPAH) have been utilized to control various chemical processes using visible light and have found many applications in materials, energy, and biomedical areas. An introduction of metastable state photoacid is given in Chapter 1. In chapter 2, to clearly understand the relationship between the structures and the physicochemical properties of mPAHs, a series of mPAHs were designed and synthesized. The reversibility, stability, reverse reaction rate, and photoreaction of the mPAHs were studied in detail using UV/VIS spectroscopy. The results demonstrated that the electron-withdrawing groups on the electron-accepting moiety enhance the overall photoreaction and stability of …
How Could Robots Successfully Elicit Help From Humans?, Layla Alarifi
How Could Robots Successfully Elicit Help From Humans?, Layla Alarifi
Theses and Dissertations
With the rapid growth of robot usages, more attention has been focused on the robots’ hardware and software to improve functionality. However, the interaction between humans and robots can be key to enhancing robots’ performance. Autonomous mobile robots may more successfully complete their tasks if they effectively solicit help from humans when they reach their limits. Hence, in this thesis, we examine three different manners, friendly, polite, and indirect, combining different interaction modalities, like speech and gestures. We conducted an experiment (involving 45 subjects) where the NAO robot addresses bystanders with the aforementioned three manners to elicit help with opening …
Analysis Of N-Alkanes And N-Alkenes In Chukchi Sea Sediments, Salomey Asantewaa Sasu
Analysis Of N-Alkanes And N-Alkenes In Chukchi Sea Sediments, Salomey Asantewaa Sasu
Theses and Dissertations
This study determined the concentrations, distribution and sources of n-alkanes in core sediments from four locations: Stations H24, H30, H32 and BarC5 in the Chukchi Sea, which is in the Arctic Ocean. n-Alkanes are valuable tracers of aquatic, terrigenous and petroleum inputs and may give evidence to the extent of climate change. The study of climate change in the Arctic is important since the Arctic is warming faster than any other part of Earth. The increase in temperature is causing enhanced evaporation leading to a higher precipitation rate and hence enhanced erosion. The n-alkanes C12-C35 were analysed and characterized using …
A Network-Driven Approach For Characterizing Emoji Usage In Social Media, Seyed Mohammad Mahdi Seyednezhad
A Network-Driven Approach For Characterizing Emoji Usage In Social Media, Seyed Mohammad Mahdi Seyednezhad
Theses and Dissertations
With the rapid growth in the number of online users, people tend to use emojis to enrich their text with emotions. In this dissertation, after an overview of the previous studies on emojis, we provide a brief introduction to emojis and the way they are constructed by the Unicode codes points. Then, we extract the emojis from messages collected from Twitter in different topics. In the first step towards analyzing the emoji usage on social media, we created the directed weighted co-occurrence network of emojis for each topic. By analyzing these networks, we realized that emoji usage has a similar …
Metastable-State Photoacid: A Comprehensive Theoretical Study Of The Photoreaction, Reverse Reaction, Thermal Isomerization, And Td-Dft Absorption In Solvent, Arwa Wasel Hamed Alharbi
Metastable-State Photoacid: A Comprehensive Theoretical Study Of The Photoreaction, Reverse Reaction, Thermal Isomerization, And Td-Dft Absorption In Solvent, Arwa Wasel Hamed Alharbi
Theses and Dissertations
The main objective of the research is to investigate the fundamentals of novel metastable-state photoacids. These photoacids can reversibly produce a large concentration of protons while undergoing photo-irradiation. This change in proton concentration can induce and catalyze chemical reactions, biological functions, and material properties that do not occur in the dark. (IMAGE) Scheme 1. Energy diagram of the photoreaction. (The red route is the forward photoreaction; the blue route is the reverse reaction; and the process that involves the proton dissociation of the photoacid in the dark is the green route; "t-" means trans- and "c-" means cis-). Scheme 1 …
Identification Of Parameters In Systems Biology, Roby Poteau
Identification Of Parameters In Systems Biology, Roby Poteau
Theses and Dissertations
Systems Biology is an actively emerging interdisciplinary area between biology and applied mathematics, based on the idea of treating biological systems as a whole entity which is more than the sum of its interrelated components. One of the major goals of systems biology is to reveal, understand, and predict such properties through the development of mathematical models based on experimental data. In many cases, predictive models of systems biology are described by large systems of nonlinear differential equations. Quantitative identification of such systems requires the solution of inverse problems on the identification of parameters of the system. This dissertation explores …
Ensemble Correlation Coefficient For Variable Association Detection, Wejdan Deebani
Ensemble Correlation Coefficient For Variable Association Detection, Wejdan Deebani
Theses and Dissertations
Subjects in a population are represented by their characteristics, and the characteristics are represented by variables. Identifying the relationship between these variables is essential for prediction, hypothesis testing, and decision making. The relation between two variables is often quantified using a correlation factor. Once correlations between response and independent variables are known, they can be used to make predictions regarding response variables. That is, if two variables are correlated, by observing one, we can make predictions about the other one. A more accurate prediction can be made where there is a strong relationship between variables. Several correlation factors have been …
Deep Space Radiation Shelter Through Magnetic Shielding, Lauren Elizabeth Eastberg Persons
Deep Space Radiation Shelter Through Magnetic Shielding, Lauren Elizabeth Eastberg Persons
Theses and Dissertations
As human space exploration begins to reach beyond Earth for the first time in 50 years, we must prepare for the eventuality of long-duration missions outside the protection of Earth's magnetic field. In interplanetary space astronauts are exposed to highly energetic galactic cosmic radiation, most commonly in the range of 1-GeV protons. Present day shielding technologies are not sufficient to protect astronauts against such particles; as such, the following paper proposes an alternate method of creating deep space radiation shelters through the use of magnetic shielding. Using a series of circular superconducting loops arranged in the shape of a shell, …
Synthesis Of Photoactive Molecules And Silicon Containing Compounds, Mozhgan Navidi
Synthesis Of Photoactive Molecules And Silicon Containing Compounds, Mozhgan Navidi
Theses and Dissertations
Retinoids are a class of synthetic and natural molecules that are functionally and structurally related to Vitamin A. They have various biological roles and potential therapeutic values. Providing treatment for eye diseases requires more detailed understanding of the visual process. However, investigating every aspect of the visual phenomenon is constrained by the difficulties involved in the synthesis of pure retinoids with the desired stereochemistry. Therefore, developing a suitable and valuable synthetic route for 11-cis-retinal and its analogues is highly desirable. The first chapter of this dissertation explains new synthetic pathways for 11-cisretinal. In addition, the total synthesis of stereoselectively deuterium-labeled …
Photocleavable Endogenous And Exogenous Molecules, Charitha Madhusanka Guruge
Photocleavable Endogenous And Exogenous Molecules, Charitha Madhusanka Guruge
Theses and Dissertations
The spatiotemporal regulation of biomolecules in their physiological environment is an essential aspect of biological research. In neuroscience, the activity of neurotransmitters can be regulated by protecting the molecules with photoresponsive protecting groups (PPGs), also known as cages. Diverse set of PPGs have been developed for caging of biomolecules. PPGs can be categorized based on their absorbing wavelengths (ranging from UV to near-IR) and photochemical properties (quantum yield, photo-cross section, solubility). PPGs absorb light and undergo intramolecular electron transitions and bond rearrangements that result in the release of the caged substrates. Hence, the caging of a specific substrate is unique …
A Probabilistic Approach To Generating Representative Wind Forcing And Wave Heights Within An Estuarine Environment, Vanessa Maria Haley
A Probabilistic Approach To Generating Representative Wind Forcing And Wave Heights Within An Estuarine Environment, Vanessa Maria Haley
Theses and Dissertations
While wind driven waves affect erosion, sediment resuspension, and flow in shallow estuaries like the Indian River Lagoon (IRL), neither winds nor waves are well observed in this environment. In order to calculate accurate significant wave heights, the winds used for the calculation must be consistent with the observed winds over the lagoon. Given the complex land/water geometry and subsequent limited fetch, a probabilistic approach is used to produce a representative wind field over the IRL. Observed winds, near the IRL, are used to sample wind distributions obtained from 180 high resolution atmospheric model simulations in order to generate a …
Ecological Responses To Eutrophication And Restoration In A Shallow Subtropical Estuary, Xiao Ma
Ecological Responses To Eutrophication And Restoration In A Shallow Subtropical Estuary, Xiao Ma
Theses and Dissertations
Like many other estuaries in the world, the Indian River Lagoon (IRL) is experiencing serious environmental health challenges in recent years. Ecosystem challenges include the connected phenomena of Harmful Algal Blooms (HABs) due to eutrophication and accumulation of fine-grained organic-rich sediments on the benthos. Fine-grained organic-rich sediments, referred to as “muck”, is a source of nutrients and fuels algal blooms in the water column, and excess particles associated with algal blooms sink to bottom and contribute to muck. This dissertation aims to better understand these problems by addressing two main objectives: first, to determine whether key herbivorous mesozooplankton have the …
Detecting Conflicts Among Autonomous Devices In Smart Homes, Fahd Alharithi
Detecting Conflicts Among Autonomous Devices In Smart Homes, Fahd Alharithi
Theses and Dissertations
Emerging technologies such as Internet-of-Things, sensors, and communication networks have been introduced into traditional homes to offer a wide range of smart home services to simplify home appliances or home care and enhance people’s lifestyles. Currently, the smart home system has been integrated with various features of the production line and equipped with multiple sensors and actuators to meet home occupants specifications by setting customized user policies. These days home automation systems have become widely adopted. When privileged users interact with a smart home system, their intents of using this system are probable to be various, which might lead to …