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Full-Text Articles in Physical Sciences and Mathematics
The Role Of Biotic And Environmental Factors In Spatial And Temporal Variability Of Indian River Lagoon Copepod Communities, Hannah G. Kolb
The Role Of Biotic And Environmental Factors In Spatial And Temporal Variability Of Indian River Lagoon Copepod Communities, Hannah G. Kolb
Theses and Dissertations
The role of zooplankton communities as the link between phytoplankton and secondary consumers is dependent on the species make-up of the copepod community. Copepods often dominate zooplankton in numbers and biomass and are frequently the dominant grazers. Species variabilities in behavioral and morphological traits, and seasonal variances in species make-up, have the potential to alter trophic dynamics in planktonic communities. The goal of this study was to identify the driving forces behind copepod community composition and better understand the role of key species in the Northern Indian River Lagoon (N-IRL). Copepods made up 76% of the N-IRL zooplankton community and …
Influence Of Ndbc Buoy Design On Sea Surface Temperature Trends In The Coastal United States, Alexander Keith Nickerson
Influence Of Ndbc Buoy Design On Sea Surface Temperature Trends In The Coastal United States, Alexander Keith Nickerson
Theses and Dissertations
The sea surface temperature (SST) record is the one of the oldest climate records, stretching back to 1662. Since that time, voluntary observing ships (VOSs) have been including these data in their ship‘s log. Due to the sparseness of VOS data, moored buoys were created to provide data at regular intervals in order to provide a more continuous record with data collection unaffected by human error. The SST sensor in National Data Buoy Center (NDBC) buoys is inside a hull and not in direct contact with the ocean. Thus, the design of the buoy may subject them to additional biases …
Studies With Dynamic Nuclear Imaging Image Reconstruction Algorithm, Haoran Chang
Studies With Dynamic Nuclear Imaging Image Reconstruction Algorithm, Haoran Chang
Theses and Dissertations
Non-negative matrix factorization (NMF) is a useful method for those non-negative multivariate data. In nuclear imaging, NMF, which is also called factor analysis, is used to analyze the 4D image of positron emission tomography and single positron emission computed tomography. Normally, we use factor analysis of dynamic structure (FADS) for the dynamic reconstruction [1]. However, this reconstruction algorithm is extremely dependent on the initial data, which means the result may be unstable when the initial data is not good enough. There are several ways for the initializing, such as splined initialized (SIFADS) [2] and clustering initialized (CIFA) [3][4]. In this …
Cross-Spectral Biometric Performance Analysis On High-Resolution Face Images, Praveen Kumar Pandian Shanmuganathan
Cross-Spectral Biometric Performance Analysis On High-Resolution Face Images, Praveen Kumar Pandian Shanmuganathan
Theses and Dissertations
Biometrics is increasingly being used to authenticate the identity of individuals in critical use case devices like smart phones, laptops, and several other access-control systems in our day-to-day lives. Additionally, biometrics is also used in forensic and security sensitive areas to detect and identify suspects involved in bombings, robberies, and several police investigations. In each of these critical scenarios, the high-quality full-frontal face images of the subjects are not accurately captured as those subjects do not intend to register their identity to the Closed-Circuit Cameras. Hence in such cases, identification of the suspects becomes difficult even though we have the …
Soteria: A Persuasive Esecurity Assistant, Punica Bhardwaj
Soteria: A Persuasive Esecurity Assistant, Punica Bhardwaj
Theses and Dissertations
“…security is only as good as the weakest link, and people are the weakest link in the chain.” – B Schneier, 2002 Humans are often referred to as the “weakest link” in the security chain because of the poor security decisions taken by them. There can be many reasons for these decisions, such as lack of understandability of the software, lack of education, and lack of relevant information required to do that particular action. In this Thesis, we focus on the lack of relevant information required at the time of performing the action. In order to provide the user with …
Discrete And Continuous Operational Calculus In Stochastic Games, Kenneth Ibe Iwezulu
Discrete And Continuous Operational Calculus In Stochastic Games, Kenneth Ibe Iwezulu
Theses and Dissertations
First, we consider a class of antagonistic stochastic games between two players A and B. The game is specified in terms of two "hostile" stochastic processes representing mutual attacks upon random times exerting casualties of random magnitudes. This game is observed upon random epochs of time and the outcome of the game is not known in real time. The game ends at the time when the underlying fixed threshold of either player is crossed (referred to as the first passage time). The first passage time is then shifted to an epoch, i.e. upon one of the observation instants of time. …
Chemical Forms Of Nitrogen In Runoff From Diverse Florida Watersheds, Jessica Emily Voelker
Chemical Forms Of Nitrogen In Runoff From Diverse Florida Watersheds, Jessica Emily Voelker
Theses and Dissertations
Watershed use along the Indian River Lagoon (IRL) on the central east coast of Florida has changed drastically during the past century, bringing with it declining water quality, eutrophication, hypoxia and fish kills. The decline of the lagoon has been directly linked to nutrient overloading; however, the sources and chemical forms of nutrients to the IRL are still not well constrained. This study was designed to determine how watershed land use impacts concentrations and fluxes of the various forms of dissolved nitrogen to the IRL. Five tributaries to the IRL were sampled monthly from July 2015 – September 2016. Storm …
The Tolerance Of Benthic Infauna To Fine-Grained Organic Rich Sediments In A Shallow Subtropical Estuary, Daniel Christopher Hope
The Tolerance Of Benthic Infauna To Fine-Grained Organic Rich Sediments In A Shallow Subtropical Estuary, Daniel Christopher Hope
Theses and Dissertations
Fine-grained organic-rich sediments (FGORS) from anthropogenic impacts are a growing concern for bays and estuaries around the world. This study explores the relationships between infaunal community diversity and species’ abundances with FGORS in the Indian River Lagoon and its tributaries. To examine these potential relationships, infauna were collected monthly using a Petit Ponar grab at 16 stations in the central Indian River Lagoon from October 2015 to August 2016. Abundant taxa in these sediments include polychaete worms (e.g., the polychaete Nereis succinea), molluscs (e.g., clam Parastarte triquetra), and arthropods (e.g., the tanaid Leptochelia dubia) with densities as high as 5.3x10⁴ …
Benthic Foraminiferal Distributions In A Shallow Subtropical Estuary And The Influence Of Environmental Factors, Maria Angelica Zamora-Durán
Benthic Foraminiferal Distributions In A Shallow Subtropical Estuary And The Influence Of Environmental Factors, Maria Angelica Zamora-Durán
Theses and Dissertations
Benthic foraminiferal communities are potentially useful tools for assessing and monitoring estuarine ecosystems and as bioindicators of water quality and pollution. To evaluate this indicator for the Indian River Lagoon (IRL) benthic ecosystem, the densities and distributions of Foraminifera were measured in Turkey Creek (Palm Bay, Florida), Crane Creek (Melbourne, Florida), and the adjacent IRL. Spatial population patterns were compared with parameters characterizing benthic sediments, including silt and clay content, organic matter (OM), and associated boundary water column conditions including salinity, temperature, and dissolved oxygen (DO. Samples (n=145) were collected from October 2015 to December 2015 at 12 locations. Four …
Phytotoxicity Of Silver Species To Egeria Densa And Applications To Phytoremediation, Leonard James Bernas
Phytotoxicity Of Silver Species To Egeria Densa And Applications To Phytoremediation, Leonard James Bernas
Theses and Dissertations
Silver species pose a significant threat to aquatic ecosystems because the use of silver nanoparticles (AgNps) for industrial applications is significantly increasing, as are discharges into waterways. The effects have only been studied on select fish and aquatic plants, so more research is needed to understand the risks associated with silver species in the environment. Egeria densa (E. densa, also known as Elodea densa), a common freshwater submerged macrophyte, was exposed to 0-1.25 ppm silver cations and 2 and 15 nm AgNps in an aqueous environment for 7 days. E. densa was chosen for this study because it is a …
Digital Quorum Sensing For Self-Organizing Malware, Mark E. Fioravanti Ii
Digital Quorum Sensing For Self-Organizing Malware, Mark E. Fioravanti Ii
Theses and Dissertations
INTRODUCTION: Malware authors present an interesting problem for the security community as they evolve and adapt to overcome network and host defenses. The determined adversary is a special class of malware author who may attempt to disrupt national interests. These adversaries may seek potentially novel Command and Control (C2) channels to coordinate their activities. Isolated and air-gapped networks pose an interesting challenge that these adversaries must adapt to in order to maintain persistence on these networks. In this work we propose that a determined adversary may seek to implement a digital quorum sensing system inspired by the quorum sensing systems …
Gbann-V: Genetically Based Artificial Neural Network With Validation For Optimal Feature Selection And Data Mining, Eric W. Worden
Gbann-V: Genetically Based Artificial Neural Network With Validation For Optimal Feature Selection And Data Mining, Eric W. Worden
Theses and Dissertations
In data mining and machine learning systems, highly predictive feature attributes help researchers and data analysts classify the problem space in the most optimal way. In this thesis paper, a feature subset selection classifier system for data mining and machine learning will be presented. This feature subset selection system will test data from the PIMA Indian Diabetes Data and the Breiman Waveform Data Set. The system collects the input features and then processes them through an evolutionary search process in order to reduce the feature space into an optimal feature set. Reducing irrelevant attributes can decrease the complexity and processing …
A Self-Organized Approach For Detecting Communities In Networks, Ben Collingsworth
A Self-Organized Approach For Detecting Communities In Networks, Ben Collingsworth
Theses and Dissertations
The community structure of networks reveals hidden information about the whole network structure that cannot be discerned using other topological properties. Yet, the importance of identifying community structure in networks to many fields such as medicine, social sciences and national security, calls for better approaches for performing this identification. The prevalent community detection algorithms, such as the one proposed by Girvan and Newman, utilize a centralized approach that is unlikely to scale to very large networks and does not handle dynamic networks. Further, existing algorithms provide limited information regarding community overlap, where an individual participates in multiple communities. We propose …
Robotic Arm Tracing Curves Recognized By Camera, Timothy Karl Findling
Robotic Arm Tracing Curves Recognized By Camera, Timothy Karl Findling
Theses and Dissertations
Applications such like soldering require robot arms to follow the soldering line as present on a surface. We assume here that the surface to be soldered is remote from the robotic arm, that the soldering is performed via a laser beam, and that the line to be followed can be a curve that may self-intersect (e.g. a crack in the material). We describe research conducted using a robotic arm pointing a laser for tracing a remote line on a smooth surface. The image of the line is converted to a one pixel width skeleton line generated from images using a …
Categorizing “Muck” In The Indian River Lagoon, Florida, Based On Chemical, Physical And Biological Characteristics, Katherine Mae Beckett
Categorizing “Muck” In The Indian River Lagoon, Florida, Based On Chemical, Physical And Biological Characteristics, Katherine Mae Beckett
Theses and Dissertations
During the past six decades, the thickness and areal extent of muck sediments have continually increased in the Indian River Lagoon (IRL), Florida. These sediments are anoxic, store and release nutrients, and destroy natural benthic habitats. The main objective of this research was to develop guidelines that help prioritize sites for muck removal based on the following: (1) biological abundance and diversity, (2) muck thickness, and (3) the physical and chemical composition of muck. Thinner muck deposits (20-40 cm), collected during two seasons at eight locations in the lagoon and adjacent creeks, had greater variability in sediment composition and ~5 …
Proactive Approach For The Prevention Of Ddos Attacks In Cloud Computing Environments, Brad Alshehry
Proactive Approach For The Prevention Of Ddos Attacks In Cloud Computing Environments, Brad Alshehry
Theses and Dissertations
Contemporary security systems attempt to provide protection against distributed denial-of-service (DDoS) attacks; however, they mostly use a variety of computing and hardware resources for load distribution and request delays. As a result, ordinary users and website visitors experience timeouts, captchas, and lowspeed connections. In this paper, we propose a new multilayer system for protection against DDoS in the cloud that utilizes Threat Intelligence techniques and a proactive approach to detect traffic behavior anomalies. The first layer of the model analyzes the source IP address in the header of incoming traffic packets and the second layer analyzes the speed of requests …
Exploring The Role Of Biofilms In The Transport And Establishment Of Invasive Marine Macrofoulers, Lynn Holly Sweat
Exploring The Role Of Biofilms In The Transport And Establishment Of Invasive Marine Macrofoulers, Lynn Holly Sweat
Theses and Dissertations
Biofilms dominated by bacteria and diatoms universally colonize submerged surfaces and mediate larval recruitment in benthic marine systems. The ability for macrofoulers to be transported by vessels and become globally established is likely affected by cues from the biofilm organisms they encounter. This study investigates how macrofoulers respond to biofilms shaped by local geography, transport processes and relocation. Biofilm assemblages in neighboring ports were largely unique to the site at which they were developed. Bacteria were primary drivers of variations among sites, and overall bacterial richness was an order of magnitude higher than has been reported for other marine environments. …
An Analysis Of The Moisture And Moist Static Energy Budgets In Amip Simulations, Kristine Adelaide Boykin
An Analysis Of The Moisture And Moist Static Energy Budgets In Amip Simulations, Kristine Adelaide Boykin
Theses and Dissertations
An analysis of the second phase of the Atmospheric Model Intercomparison Project (AMIP) simulations has been conducted to understand the physical processes that control precipitation in the tropics. This is achieved primarily through the analysis of the moisture and moist static energy budgets. Overall, there is broad agreement between the simulated and observed precipitation, although specific tropical regions such as the Maritime Continent poses challenges to these simulations. The models in general capture the latitudinal distribution of precipitation and key precipitating regions including the Inter-Tropical Convergence Zone (ITCZ) and the Asian Monsoon. The simulations portrayed the global patterns of evaporation …
Simulating Bottom Reflectance Retrievals Using An Analytical Solution For The Two-Flow Irradiance Models, Tyler A. Rotkiske
Simulating Bottom Reflectance Retrievals Using An Analytical Solution For The Two-Flow Irradiance Models, Tyler A. Rotkiske
Theses and Dissertations
Existing analytical solutions to the two-flow irradiance equations are used to obtain new relations for simulating hyperspectral bottom reflectance signatures. Synthetic bottom reflectance signatures are compared to measured bottom reflectance signatures in order to test the model equation limitations of the formulations. Measured hyperspectral bottom reflectance signatures for a dead reef, Elkhorn coral, seagrass and sand, sand, and turtle grass are used. Estimated collimated and diffuse irradiances are inputs needed to run model formulations. Also, specific absorption, specific backscattering coefficients, and water depth for ocean, coastal, and estuarine waters are used as inputs to simulate bottom reflectance retrievals. The specific …
Surface Cooling Due To Precipitation In The Tropics, Camila Gomes Martins Ramos
Surface Cooling Due To Precipitation In The Tropics, Camila Gomes Martins Ramos
Theses and Dissertations
Precipitation is an important component of the global hydrological cycle. It affects the upper ocean salinity by adding freshwater to the ocean. In addition, precipitation plays a role in cooling the ocean and land surfaces, when the temperature of the raindrops is lower than the temperature of the surface. However, the surface cooling due to precipitation (QP) remains an overlooked feature and is not included in the Intergovernmental Panel on Climate Change (IPCC) models. One might expect that heavy precipitation events may lead to large QP, which can impact the surface temperature, surface energy balance, and local- to regional-scale circulations. …
Analysis Tools And Defense Mechanisms For Dos Hash Attacks, Pratick Henry Bakhtiani
Analysis Tools And Defense Mechanisms For Dos Hash Attacks, Pratick Henry Bakhtiani
Theses and Dissertations
This thesis focuses on creating tools for the gathering and management of data for analyzing Denial of Service attacks on the advertisement-based synchronization mechanism used in the DirectDemocracyP2P application. In this report we present two tools that were developed as part of this eort: AttackerClient and Decoding and Distribution. These tools are used to perform the attack and analyze the captured network packets of the attack data, storing them in a database. The Decoding and Distribution tool can distinguish between dierent types of messages. It can also assemble fragmented messages from UDP chunks. The created tools help to manage a …
Geological Conditions Required For The Fluvial Erosion Of Titan’S Impact Craters, Rebeca M. Kinser
Geological Conditions Required For The Fluvial Erosion Of Titan’S Impact Craters, Rebeca M. Kinser
Theses and Dissertations
In comparison to other icy satellites, Titan has a small number of impact craters on its surface. Its dense atmosphere screens smaller impactors from the surface, but this alone does not account for the lack of impact craters, especially at large diameters. This suggests that Titan has a relatively young surface and/or erosional processes have effectively removed craters from its surface. For example, fluvial erosion could degrade craters such that they would be unrecognizable from an orbiting spacecraft such as Cassini. The amount of erosion, however, will depend on a number of factors including the geological and meteorological conditions of …
Reverberation Mapping Of The Dusty Torus In Active Galactic Nuclei, Erich Franz Geisert
Reverberation Mapping Of The Dusty Torus In Active Galactic Nuclei, Erich Franz Geisert
Theses and Dissertations
The Dusty Torus is a structure that is believed to exist in Active Galactic Nuclei. The Torus is physically too small to be spatially resolved, so Reverberation Mapping can be performed in order to replace spatial resolution with temporal resolution, yielding observations that can unravel the mystery of the Dusty Torus. One of the unknowns about the Torus is how the dust is distributed. The two competing theories are that either the dust resides in discrete clouds or that there is a solid wall of dust. This thesis presents the results of a year long observation program, starting in August …
Robust Structured Tracking, Ivan Bogun
Robust Structured Tracking, Ivan Bogun
Theses and Dissertations
Model-free visual tracking is an important problem in computer vision. The abundance of applications make the problem attractive, and, as a result, significant progress was made, especially in the recent years. A number of reasons make tracking a hard problem: change of lighting conditions throughout the video, change of scale and rotation of the object, as well as frequent and occlusions. In this dissertation, we build upon a tracker known as Struck, which is based on a structured support vector machine. To make the structured tracker robust, we improve it in a number of ways. To make the structured tracker …