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Sediment Oxygen Demand And Stoichiometry Of Irl Nutrient Fluxes, Iulia Bibire
Sediment Oxygen Demand And Stoichiometry Of Irl Nutrient Fluxes, Iulia Bibire
Theses and Dissertations
Eutrophication of coastal systems has become a prominent global issue with a variety of detrimental effects, one of these being the shift in the composition of phytoplankton communities often promoting harmful algal blooms (HABs) resulting at least partially from changes to the relative abundance of N:P:Si. This study investigated nutrient fluxes from muck, a fine-grained and organic-rich sediment, and from sand to determine the importance of these sediments with regards to regulating N:P ratios in the water column. Overall sediment oxygen demand (SOD) was used as an indicator of aerobic decomposition and was found to decrease from north to south …
A Machine Learning Approach To Forecasting Sep Events With Solar Activities, Jesse Scott Torres
A Machine Learning Approach To Forecasting Sep Events With Solar Activities, Jesse Scott Torres
Theses and Dissertations
Solar energetic particles (SEPs) are fast-moving events which can cause severe damage to astronauts and their equipment, and can disrupt communications on Earth. There are no clear patterns in solar activities which indicate whether an SEP is about to occur, making physics-based methods inaccurate for SEP forecasting. Therefore, in order to provide an advance warning so that astronauts are able to get to safety, we apply neural networks to the problems of forecasting SEP occurrence and intensity. Our algorithm for predicting SEP occurrence uses a combination of observed CME properties and derived features and achieves a TSS of 0.846 and …
A Fast And Exact Motif Enumeration Algorithm For Dynamic Networks, Abbas Al-Thaedan
A Fast And Exact Motif Enumeration Algorithm For Dynamic Networks, Abbas Al-Thaedan
Theses and Dissertations
From social to biological networks, prior research in complex networks have demonstrated the importance of the frequency and distribution of different types of motifs to important network functions and properties. A network motif (or graphlet) is defined as a small connected sub-pattern which is over-represented in a network. Network motifs have been widely applied in a wide range of applications, namely biological, social, and technical networks. The counting of the network motif involves expensive enumeration of graph sub-patterns along with the detection of graph isomorphism. In general, network motif detection algorithms are computationally expensive and often designed to operate over …
Real-Time Full Face Closed Eyes Detection, Lucas De Morais Tramasso
Real-Time Full Face Closed Eyes Detection, Lucas De Morais Tramasso
Theses and Dissertations
Intelligent systems based on machine-learning techniques are becoming a common way of solving problems in many different areas. In this thesis, our goal is to apply machine learning to a computer vision problem. We propose a new solution to detect closed eyes in full-face images. Accurate detection of closed eyes can be used in many problems such as driver drowsiness detection, human-computer interaction, and computer user monitoring. Most algorithms used to detect blinks or closed eyes follow a similar workflow. They require detection of a region of interest that is then used with different algorithms and techniques to determine if …
Optimization Framework For Reconstructing Biomedical Images By Efficient Sample-Based Parameterization, Paul Richard Arbic Ii
Optimization Framework For Reconstructing Biomedical Images By Efficient Sample-Based Parameterization, Paul Richard Arbic Ii
Theses and Dissertations
An efficient computational approach for optimal reconstruction of binary-type images suitable for models in various biomedical applications is developed and validated. The methodology includes derivative-free optimization supported by a set of sample solutions with customized geometry generated synthetically. The entire framework has an easy to follow design due to a nominal number of tuning parameters which makes the approach simple for practical implementation in various settings, adjusting it to new models, and enhancing the performance. High efficiency in computational time is achieved through applying the coordinate descent method to work with individual controls in the predefined custom order. This technique …
Refinements Of The Concept Of Privacy In Distributed Computing, Entisar Seedi Alshammry
Refinements Of The Concept Of Privacy In Distributed Computing, Entisar Seedi Alshammry
Theses and Dissertations
In light of the tremendous development of technology in the modern world in which we live, privacy concerns are increasing, especially after the massive spread of distributed computing systems and the technologies that depend on it, whether in personal devices or public services. Hence, this research proposes refinements on the concept of privacy for enhancing the development of privacy-related strategies in distributed computing systems to address the elements of privacy. In particular, the study introduces the new concept of Privacy Appetite to describe and model the nature of the relationship between the intended disclosure of private information and gained value …
Real-Time Action Classification Using Intermediate Skeletal Pose Estimation, Kleanthis Zisis Tegos
Real-Time Action Classification Using Intermediate Skeletal Pose Estimation, Kleanthis Zisis Tegos
Theses and Dissertations
The topic of Human Action Classification has attracted significant interest these past years, which can be attributed to the advancements in deep learning methodologies. Its applications range from robotics to surveillance and automated video categorization, as well as in the healthcare industry. The literature, however, has primarily focused on offline action classification, without significant attention being given to the constraints of an online real-time classifier. Using an intermediate skeletal representation of humans, while convoluted, provides a scalable means of tackling the action classification problem. This project discusses the existing literature, and adapts two of the state-of-the-art approaches for real-time analysis. …
Biometric Face Skintone Data Augmentation Using A Generative Adversarial Network, Rosalin Dash
Biometric Face Skintone Data Augmentation Using A Generative Adversarial Network, Rosalin Dash
Theses and Dissertations
Researchers seek methods to increase the accuracy and efficiency in identifying an individual using facial biometric systems. Factors like skin color, which may affect the accuracy of facial recognition, need to be investigated further. To analyze the impact of race with respect to skin color of face on biometric systems, we focused on generating a dataset with uniformly distributed images of different skin tones while preserving identities. Deep learning neural network architectures like the generative adversarial network (GAN) focus on modifying only certain features of the face like the color of the skin. In our experimental approach, we implemented a …
Polymer-Based Capacitive Gas Sensor For Machine Olfaction, Mohamed Fathy Hassan
Polymer-Based Capacitive Gas Sensor For Machine Olfaction, Mohamed Fathy Hassan
Theses and Dissertations
Transferring human abilities and knowledge to machines has been the focus of decades of work by scientists and engineers. With the progress in computation power and algorithms such as artificial neural networks, machines have surpassed humans in complicated games like chess and the Chinese game Go. Some senses can be mimicked including touch, with pressure sensors, hearing, with microphones, and vision with charged couple device (CCD)imaging chips. Yet, relatively little progress has been made with the senses of smell and taste. Machine olfaction, the ability to detect and quantify vapors in the environment, poses a range of challenges, which if …
Controlling Framing Effects For Web-Based Group Decision Support Systems, Badria Sulaiman Alfurhood
Controlling Framing Effects For Web-Based Group Decision Support Systems, Badria Sulaiman Alfurhood
Theses and Dissertations
The way the proposal and the available alternatives are presented or framed for a group decision may alter the ultimate group decision. Strategic framing is an attack method used to manipulate people into irrationally preferring a particular alternative. The adverse effects of framing threaten the trustworthiness and results of the group decision support systems (GDSSs). Nonetheless, the avoidance or reduction of framing effects is possible. Negative framing effects arise when users are not consistent with their choices if framing is applied for a collaborative decision using GDSSs. In this interdisciplinary research, human-computer interaction (HCI) informed methods, cognitive science, and political …
Effect Of Electron Demand On Sensing Behavior Of Carbazolopyridinophanes, Grace Abban
Effect Of Electron Demand On Sensing Behavior Of Carbazolopyridinophanes, Grace Abban
Theses and Dissertations
Hydrazine (HZ), monomethylhydrazine (MMH), and 1,1-dimethylhydrazine (UDMH) are widely used as high energy rocket propellants in bipropellant rocket engines. However, hydrazine and its derivatives are highly flammable and carcinogenic. Currently, hydrazine sensors used for detection are irreversible which makes them costly. Two proposed carbazolopyridinophanes containing intramolecular hydrogen bonds were synthesized to detect hydrazine as real-time reversible sensors. However, their thresholds for detection (100 and 25 ppb for CPand 22OMeCPrespectively) were above the regulatory limit of 10 ppbdue to background fluorescence. It was established that the quenching of carbazole in the presence of the CP system has a direct correlation to …
Optimal Control Of Multiphase Free Boundary Problems For Nonlinear Parabolic Equations, Evan Cosgrove
Optimal Control Of Multiphase Free Boundary Problems For Nonlinear Parabolic Equations, Evan Cosgrove
Theses and Dissertations
Dissertation research is on the optimal control of systems with distributed parameters described by singular nonlinear partial differential equations (PDE) modeling multi-phase Stefan type second order parabolic free boundary problems. This type of free boundary problems arise in various applications, such as biomedical engineering problem on the laser ablation of biological tissues, aerospace engineering problem on the ice accretion in aircrafts mid-flight, biomedical problem on the growth of cancerous tumor, and many other phase transition processes in thermophysics and fluid mechanics. The aim of the optimal control of distributed free boundary systems is two fold: identification of functional parameters of …
Using Disruptive Coloration And Ultraviolet Light To Prevent Barnacle Settlement, Kailey Nicole Richard
Using Disruptive Coloration And Ultraviolet Light To Prevent Barnacle Settlement, Kailey Nicole Richard
Theses and Dissertations
Biofouling or the accumulation of unwanted micro and macro organisms is problematic for the shipping industry. Barnacles are one of the most abundant fouling organisms and their settlement on ship hulls can result in costly damage. Several methods have been developed to prevent the formation of biofouling, including antifouling coatings and mechanical techniques, but the search for more effective and environmentally friendly solutions is still ongoing. This thesis investigated two methods aimed at barnacle prevention: color patterning and the application of ultraviolet light. The first method utilized disruptive coloration, a common mechanism observed in nature by terrestrial organisms (i.e. butterflies) …
Organic Sediment Impacts On Seagrasses And Their Associations With Benthic Fauna, Sean Matthew Crowley
Organic Sediment Impacts On Seagrasses And Their Associations With Benthic Fauna, Sean Matthew Crowley
Theses and Dissertations
Human-population growth and rapid rates of urbanization have led to eutrophic conditions in estuaries throughout the world. Effects often include severe algal blooms, decreased dissolved oxygen levels, and the accumulation of fine-grained organic-rich sediments. One frequent negative consequence of eutrophication is the decline of seagrasses, a vital component of coastal ecosystems. Seagrasses provide shelter from predation, serve as nursery habitat, stabilize sediments, act as a sink for excess carbon, produce oxygen, and are a food source for many herbivores. Seagrasses are also sensitive to environmental changes, such as declining water quality and increased sedimentation rates. This study examines the impacts …
Numerical Simulation Of Low Reynolds Number Locomotion In Viscoelastic Media, Nesreen Abdulrahim Althobaiti
Numerical Simulation Of Low Reynolds Number Locomotion In Viscoelastic Media, Nesreen Abdulrahim Althobaiti
Theses and Dissertations
We use computational models to investigate 2D swimmers within various fluid media with low Reynolds Number. Extensions of the standard Immersed Boundary (IB) Method are proposed so that the fluid media may satisfy no slip, partial slip or free-slip conditions on the moving boundary. The fluid equations are solved through a Multigrid preconditioned GMRES solver. Our numerical results indicate that slip may lead to substantial speed enhancement for swimmers in a viscoelastic fluid, as well as in a viscoelastic two-fluid mixture. Under the slip conditions, the speed of locomotion is dependent in a nontrivial way on both the viscosity and …
A Web-Based User-Interface For Internet Of Things Device Management, Leena Mansour Alghamdi
A Web-Based User-Interface For Internet Of Things Device Management, Leena Mansour Alghamdi
Theses and Dissertations
With the growing advances in the Internet of Things (IoT) technology, which combines various devices with distinct functions, capabilities, and communication protocols, it is essential to provide a platform that enables IoT users to interact with their IoT devices directly and be able to manage them effortlessly via that platform from various locations at any time in order to protect their privacy when using IoT devices. In this study, we are aiming to provide a web-based user interface that can address that challenges and provide real-time data control; hence, we have created a user interface prototype, which can demonstrate the …
Analysis Of Fatty Acids In Chukchi Sea Sediments, Damilola Ajadi
Analysis Of Fatty Acids In Chukchi Sea Sediments, Damilola Ajadi
Theses and Dissertations
The Arctic Ocean and its marginal seas are key areas for understanding the global climate system. Climate change causes increased terrigenous materials to be carried into the ocean as well as higher production of marine organic matter in the ocean. This study determined the concentrations, distribution, and sources of fatty acids in core sediments from four locations: Stations H32, H30, BarC5 and H24 in the Chukchi Sea, which are in the Arctic Ocean. Fatty acids are valuable tracers of marine or terrigenous inputs and may give evidence to the extent of climate change. Fatty acids were analyzed, characterized using GC-MS …
Iot Tracking System Effectiveness In Enhancing Library Services, Khulud Alawaji
Iot Tracking System Effectiveness In Enhancing Library Services, Khulud Alawaji
Theses and Dissertations
The advantages that the Internet of Things (IoT) provides lead to an increase in the number of IoT solutions that integrate different fields. One of the important IoT contributions is in location-based IoT applications, which leverage the Indoor Positioning System (IPS) technology. IPS uses numerous technologies; one is the Beacon technology, which is based on a small wireless sensor device used to send signals. IPS based Beacon technology used in college libraries to increase the productivity, accuracy, safety, and efficiency of daily processes. This research proposed an IoT Beacon-based tracking system concept to be applied at Evans Library at Florida …
Dynamics In Recommendations Of Updates For Free Open-Source Software, Shakre Elmane
Dynamics In Recommendations Of Updates For Free Open-Source Software, Shakre Elmane
Theses and Dissertations
In Free and Open-Source Software (FOSS) world, newer is not always better. Automatically updating to the latest version of FOSS applications involves real risks. The newer version could be missing features that are essential to some users, but are dropped by the developers. Another possible scenario, with even more serious consequences, is a project taken over by malicious developers who target users’ sensitive data, or try to control their systems. In this work we identify a set of security risks associated with changes of reviewers in automatic Free and Open-Source software (FOSS) updates. Automatic updates can be a prime target …
Blockchain Interoperability With Cross-Chain Stablecoin Payments, Ravi Balvantrai Pandhi
Blockchain Interoperability With Cross-Chain Stablecoin Payments, Ravi Balvantrai Pandhi
Theses and Dissertations
A Peer-to-peer payment system was one of the first proposed applications of blockchain technology. Cryptocurrencies have instead been used as a speculative investment. Stablecoins worth approximately 7 billion USD circulate the cryptocurrency market today, presenting a good case for their use in cryptocurrency payments [2]. Stablecoins have also been issued on a variety of blockchains that operate balkanized from each other. Cross-chain transfer between stablecoins is currently enabled by centralized middlemen. The actions of putting stablecoin transfer in the hands of intermediaries is a path towards centralization of control opposite to the decentralization ideology of blockchains. The inter blockchain transfer …
Discrete Moment Problems With Logconcave And Logconvex Distributions, Talal Alharbi
Discrete Moment Problems With Logconcave And Logconvex Distributions, Talal Alharbi
Theses and Dissertations
We introduce new shape constraints, logconcavity and logconvexity, to discrete moment problems for bounding the k-out-of-n type probabilities and expectations of higher order convex functions of discrete random variables with non-negative and finite support. The bounds are obtained as the optimum values of non-convex and convex nonlinear optimization problems, where the non-convex problem is reformulated as a bilinear optimization problem. We present numerical experiments to show the improvement in the tightness of the bounds when the shape of underlying unknown probability distribution is prescribed into discrete moment problems. We apply our optimization based bounding methodology in an insurance problem to …
Characterization Of Written Text Using Data And Network Science, Harith A. Hamdon Hamoodat
Characterization Of Written Text Using Data And Network Science, Harith A. Hamdon Hamoodat
Theses and Dissertations
The success of humans cannot be attributed to language, but it is certainly true that language and humans are inseparable. Since the first language appeared, we have seen that language continually evolving over space and social gatherings to formed around 7,000 languages today. The origin and evolution of languages still vague, and state-of-the-art in languages evolution still lack a comprehensive characterization. In general, this problem is mainly tackled by statistical measuring the changes on the part of the language ( e.g., words and sounds). Given the current availability of data and computational power, this dissertation proposes a comprehensive data-driven characterization …
Blockchain For Educational Certificate Distribution, Layla Asiri
Blockchain For Educational Certificate Distribution, Layla Asiri
Theses and Dissertations
There are many authenticity problems associated with paper certificates and diplomas. Besides the increase in the forgery of paper certificates and diplomas, other quality problems regarding paper certificates and diplomas deserve attention too. This study seeks to evaluate how alternative technologies may mitigate concerns for Florida Institute of Technology students and faculty and determine whether they support the adoption of Blockchain technology. In particular, this research aims to investigate the challenges of using Blockchain technology for issuing and verifying academic records, certificates, and diplomas for Florida Institute of Technology students and faculty. Blockchain technology can be difficult for institutions to …
A Blockchain Approach For Negotiating Trust In Iot, Skailer Knezevic
A Blockchain Approach For Negotiating Trust In Iot, Skailer Knezevic
Theses and Dissertations
“The internet is no longer a web that we connect to. Instead, its a computerized, networked, and interconnected world that we live in. This is the future, and what were calling the Internet of Things.”- Bruce Schneier, 2019 The Internet of Things is becoming a big part of our lives. Every year there are more devices with the capability to connect on the internet and communicate with each other. Today there are over 400 million IoT devices in the world, and this number is predicted to grow to 1.5 billion devices by 2022 [14]. It is becoming more difficult to …
Practical Adversarial Attacks Against Black Box Speech Recognition Systems And Devices, Yuxuan Chen
Practical Adversarial Attacks Against Black Box Speech Recognition Systems And Devices, Yuxuan Chen
Theses and Dissertations
With the advance of speech recognition technologies, intelligent voice control devices such as Amazon Echo have became increasingly popular in our daily life. Currently, most state-of-the-art speech recognition systems are using neural networks to further improve the accuracy and efficacy of the system. Unfortunately, neural networks are vulnerable to adversarial examples: inputs specifically designed by an adversary to cause a neural network to misclassify them. Hence, it becomes imperative to understand the security implications of the speech recognition systems in the presence of such attacks. In this dissertation, we first introduce an effective audio adversarial attack towards one white box …
A Bio-Inspired Classification System For Cyber-Physical-Human Identity Resolution, Mary Catherine (Kay) Michel
A Bio-Inspired Classification System For Cyber-Physical-Human Identity Resolution, Mary Catherine (Kay) Michel
Theses and Dissertations
The Internet has created a need for understanding complex technology and identities today. Cybercrime can take years to solve, and a systematic design may aid in more rapid resolution. Classification of identities involves the arrangement of shared qualities or characteristics known as features set expression, useful for identifying specific types of cybercriminals based on empirical evidence and logic. In order for classification of a cyber identity to be explainable and acceptable to researchers, a holistic systematic approach is beneficial to organize natural and synthetic features of living and non-living organisms into a standardized model. Proven scientific methods in the biology …
A Computational Investigation Of The Biomechanics For Platelets Aggregation, Ghadah Mohammed Alhawael
A Computational Investigation Of The Biomechanics For Platelets Aggregation, Ghadah Mohammed Alhawael
Theses and Dissertations
The proximal cause of most heart attacks and many strokes is the rapid formation of a blood clot (thrombus) in response to the rupture or erosion of an arterial atherosclerotic plaque. The formation of a thrombus in arteries is a very complex process whose workings are subjects of intense research. In this dissertation, we investigate the biomechanics of platelet aggregation in large arteries using a two-phase continuum computational model. The model tracks the number densities of various platelet populations, the concentration of one platelet-activating chemical, as well as the number densities of inter-platelet bonds. Through the formation of elastic bonds, …
Iot-Based Solutions For Privacy-Preservation During Interaction With Assistive Robotics, Tahani Ali Albuluwi
Iot-Based Solutions For Privacy-Preservation During Interaction With Assistive Robotics, Tahani Ali Albuluwi
Theses and Dissertations
As mobile robot technologies become pervasive in daily life settings and share physical space with regular people, privacy concerns and complications arise. In particular, the independent and enhanced mobility features of mobile robots raise the potential of privacy violations through continuous surveillance, access to privacy-sensitive locations, or opportunities for witnessing embarrassing situations. In this paper, an IoT-based solution concept called PrivateLoc is proposed to empower end-users with the ability to use smartwatches to restrict robot perception and movement at home dynamically according to end-users’ privacy preferences, conditions, or locations. Thus, descriptive research was conducted using structured surveys with 104 participants, …
Optimal Control Of Coefficients For The Second Order Parabolic Free Boundary Problems, Ali Hagverdiyev
Optimal Control Of Coefficients For The Second Order Parabolic Free Boundary Problems, Ali Hagverdiyev
Theses and Dissertations
Dissertation aims to analyze inverse Stefan type free boundary problem for the second order parabolic PDE with unknown parameters based on the additional information given in the form of the distribution of the solution of the PDE and the position of the free boundary at the final moment. This type of ill-posed inverse free boundary problems arise in many applications such as biomedical engineering problem about the laser ablation of biomedical tissues, in-flight ice accretion modeling in aerospace industry, and various phase transition processes in thermophysics and fluid mechanics. The set of unknown parameters include a space-time dependent diffusion, convection …
Optimal Control Of The Second Order Elliptic Equations With Biomedical Applications, Saleheh Seif
Optimal Control Of The Second Order Elliptic Equations With Biomedical Applications, Saleheh Seif
Theses and Dissertations
Dissertation analyzes optimal control of systems with distributed parameters described by the general boundary value problems in a bounded Lipschitz domain for the linear second order uniformly elliptic partial differential equations (PDE) with bounded measurable coefficients. Broad class of elliptic optimal control problems under Dirichlet or Neumann boundary conditions are considered, where the control parameter is the density of sources, and the cost functional is the L2-norm difference of the weak solution of the elliptic problem from measurement along the boundary or subdomain. The optimal control problems are fully discretized using the method of finite differences. Two types of discretization …