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Protecting infrastructure networks from disinformation
Get PDFMassive amount of information shared on online platforms makes the verification of contents time-consuming.
Concern arises when the misleading or false information, called "disinformation", is exposed to many online platform users who have potential to react on it.
The spread of disinformation can cause malicious consequences such as damage to critical infrastructure networks such as electric power, gas, and water distribution networks.
Imagine a fake electricity discount, shared by disinformation campaigns, is exposed to many users on Twitter encouraging them to shift their electricity usage to a specific peak hour.
If the population of users who engage with the fake discount exceeds a threshold, a blackout can happen due to the overconsumption of electricity.
Thus, users access and exposure to accurate information on time can reinforce the infrastructures which are backbone of well-being for societies and economic growth.
In this dissertation, we propose solutions to protect infrastructure networks from disinformation campaigns.
The solutions include:
(i) an integrated epidemiological-optimization (EPO) model involving a mixed integer linear programming model (MIP) and SIR (Susceptible, Infected, Recovered) model to protect physical infrastructure networks by counter disinformation (accurate information) spread in information networks,
(ii) a disinformation interdiction model to influence physical infrastructure commodity consumers with accurate information given the topology of social network,
(ii) a robust mixed integer linear programming model to propose solutions superior to the original EPO model under uncertain spread of disinformation scenarios.
We illustrate our proposed models with two different case studies: (i) a sub-network of the western US interconnection power grid located in Los Angeles County in California, and (ii) the New York City subway system
Experimental Investigation of a Novel Working Fluid for Heat Extraction In Geothermal Wells
No full textThe exponential increase in the global atmospheric carbon dioxide has spurred research interest in the exploration and maximization of renewable energy exploits. This interest has in turn inspired the growth of the geothermal industry and has provided a great opportunity for the repurposing of inactive wells in the Midwest, Northeast and South region of the United States as these regions have been marked with significant carbon dioxide emissions. Despite the created opportunities, these regions are faced with a limitation of low enthalpy geothermal resources, which makes it challenging to extract large amount of heat energy without drilling deeper, thus it is pertinent to explore suitable geothermal primary working fluids which can maximize the heat extraction at these regions with low to medium enthalpy geothermal resources.
Conventionally, water is utilized as the geothermal primary working fluid, however, it is described by its high rate of corrosion, low boiling point and its high critical conditions. Studies have suggested that the high critical conditions of water poise a challenge to the rate of heat transfer, hence, supercritical carbon dioxide (CO2) has been suggested as a potential geothermal working fluid due its favorable properties, such as its low viscosity, low specific heat capacity, and low critical conditions. However, due to the high purchasing cost of CO2, additional costs associated with its insulation around the production well sections, and its limited application to low reservoir temperatures from research studies, it has constrained utilization. Molten salts asides from being relatively cheap have been reported to have excellent heat transfer fluid properties such as good thermal stability at high temperatures, low corrosion rates as it has been described to be a strong passivating agent with the materials used in the transfer of heat, and low vapor pressures as it has strong intermolecular forces which enables the unease to evaporation, thus high boiling point. These properties can present significant benefits when water is being beneficiated with molten salts, particularly nitrate salts as the passivation agent in nitrate salts could result in a reduction of the rate of corrosion in the resulting solution. The low vapor pressure of the salt could also extend the useful operating liquid temperature of the solution above the boiling point of water. This has the overall benefit of retaining or increasing the heat transfer efficiency of the resultant solution.
In this study, a novel working fluid formulated with molten nitrate salt was experimentally investigated for heat extraction in geothermal wells. A corrosion immersion test was performed to compare the rate of corrosion between the proposed novel fluid and water. Additionally, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) was utilized to validate the passivating property of the novel fluid, which led to a reduction in the corrosion rate when compared to water. The effect of the novel fluid and water on the mineralogy of a known rock sample was further examined using X-ray Diffraction, SEM-EDS, and Fourier transform infrared (FTIR) to determine changes in the mineral spectrum of the rock sample. Finally, a heat transfer setup was developed and used to investigate the convective heat transfer coefficient and the thermal energy generated for the different working fluids at various testing conditions. Comparative analysis was further conducted to determine the effect of fluid properties and operating conditions on the heat transfer coefficient and the thermal energy generated.
The findings from this research study illustrate the significant benefits of the developed novel working fluid compared to water as the novel fluid exhibited favorable thermal properties yielding more thermal energy generation. The novel fluid was observed to reduce the rate of corrosion by over 30% and 60% at 77◦F and 150◦F when compared with water across all tested aging time. Generally, it was observed that the temperature effect on viscosity as well as changes in the flow rate, significantly affected the convective heat transfer coefficient while the thermal energy was observed to be significantly affected by the fluid differential temperature, the flow rate, and the specific heat capacity
Avian behavior in a changing world: how human effects change behavioral expression at the individual, population, and community level
Get PDFHuman induced rapid environmental change (HIREC) is one of the largest threats to avian biodiversity and abundance (Rosenberg et al. 2019; Sih, Ferrari, and Harris 2011). Since selection acts on individual behavioral variation first, understanding which behavioral phenotypes are favored under these new selection pressures is necessary to understand how HIREC will eventually affect populations and communities (Alley et al. 2003; Bergstrom et al. 2015). With climate change acting so quickly, organisms have little time to respond and adapt to the novel conditions they face (Radchuk et al. 2019; Sih 2013). Under these altered conditions, selection may favor behavioral phenotypes that are maladaptive, such as individuals favoring a resource that lowers fitness, i.e. an ecological trap (Dwernychuk and Boag 1972; Robertson, Rehage, and Sih 2013). Understanding how maladaptive behaviors are selected from a spectrum of available behavioral phenotypes can help us reduce trap susceptibility and potentially even prevent ecological traps from occurring.
Behavioral plasticity is necessary for an individual adjust to HIREC to avoid fitness loss and death. Understanding how phenotypic plasticity responds to a changing environment can aid us in understanding how these individuals will persist in HIREC. However, we do not know the limits of behavioral flexibility under these extremely altered conditions. While activational behavioral plasticity (i.e. behavioral flexibility) can help individuals respond to immediate extreme events, developmental plasticity (i.e. plasticity) can limit the types or number of responses an individual can produce (Buchholz et al. 2019; Both et al. 2004). Understanding these behavioral flexibility and plasticity limits can help us understand how individuals can mitigate the negative consequences of HIREC and give us an idea of future trait selection.
This dissertation focused on how HIREC will affect avian behavioral responses, at the individual, population, community level in birds. My first chapter focuses on the effects of elevated noise levels on avian parental care and nestling development in eastern bluebirds (Sialia sialis). Anthropogenic noise is a ubiquitous feature of the American landscape, and is a known stressor for many bird species, leading to negative effects in behavior, physiology, reproduction, and ultimately fitness. While many studies examined how anthropogenic noise affects avian fitness, few also examined how noise impacts the relationship between parental care behavior and nestling fitness. We conducted Brownian noise playbacks for six hours a day during the nesting cycle on Eastern Bluebird (Sialia sialis) nest boxes to investigate if experimentally elevated noise affected parental care behavior, nestling body conditions, and nestling stress indices. We documented nest attendance by adult females using radio frequency identification (RFID), and we assessed nestling stress by measuring baseline corticosterone levels and telomere lengths. Adult bluebirds exposed to noise had significantly higher feeding rates earlier in the brood cycle than adults in the control group, but reduced feeding rates later in the cycle. Nestlings exposed to noise had higher body conditions than the control nestlings at eleven days of age, but conditions equalized between treatments by day fourteen. We found no differences in nestling baseline corticosterone levels or nestling telomere lengths between the two treatment groups. Our results revealed that noise altered adult behavior, which corresponded with altered nestling body condition. However, the absence of indicators of longer-term effects of noise on offspring suggests adult behavior may have been a short-term response.
My second chapter focused on simulating how current and future climate conditions alter avian soundscapes using agent-based models, and how individual vocalizing behavior can impact the entire population. Climate change is increasing aridity in grassland and desert habitats across the southwestern United States, reducing available resources and drastically changing the breeding habitat of many bird species. Increases in aridity will reduce sound propagation distances, potentially impacting habitat soundscapes, and leading to a breakdown of the avian soundscapes, which could lead to the loss of vocal culture, reduced mating opportunities, and local population extinctions. We developed an agent-based model to examine how changes in aridity will affect both sound propagation and the ability of territorial birds to audibly contact their neighbors. We simulated vocal signal attenuation under a variety of environmental scenarios for the south central semi-arid prairies of the United States, ranging from contemporary weather conditions to predicted extremes under climate change. We also simulated how changes in physiological conditions, mainly evaporative water loss (EWL) would affect singing behavior. Under extreme climate change conditions, we found significantly fewer individuals successfully contacted all adjacent neighbors than did individuals in either the contemporary or mean climate change conditions. We also found that at higher sound frequencies and higher EWL, fewer individuals were able to successfully contact all of their neighbors, particularly in the extreme and extreme climate change conditions. These results indicate that climate change-mediated aridification may disrupt the avian soundscape, such that vocal communication no longer effectively functions for mate attraction or territorial defense. As climate change progresses increased aridity in current grasslands may favor shifts toward low frequency songs, colonial resource use, and altered songbird community compositions.
My third and final chapter tested the conclusions outlined in chapter 2 on how avian singing activity and species composition vary across local climate conditions and access to water resources. Climate change is increasing aridity across multiple habitats throughout the world, which is likely reducing critical resources for songbirds in environments that are already resource limited. In addition to reducing food and water availability, increased aridity can reduce sound transmission distances and impose stress in the form of evaporative water loss on singing birds. To determine how aridity and water access affect avian vocal activity and detectability, we used automated recording units (ARUs) to sample soundscapes in shrub- and grassland ecosystems across an aridity gradient in Oklahoma, Texas, and New Mexico. We also examined the effect of water availability experimentally by providing supplemental water in two of the study sites. Avian vocal behavior decreased with increasing aridity across sites but was consistent across the morning acoustic period. Supplemental water did lead to increased detectable vocal behavior during arid conditions but only in one of the supplemental water experiments. During extremely arid conditions, only the most arid sites demonstrated significant negative responses, indicating these communities have some resilience to increasing aridity. Reduced vocal communication due to high aridity could be a warning sign of at-risk avian communities in some arid environments. Future studies should focus on how community composition and vocal characteristics change under increasing aridity
Design, Development, and Characterization of a Low Velocity Impact System
Get PDFThis paper introduces low-velocity impacts (LVI), presents a concept for evaluating them, tests various materials for proof-of-concept, and discusses how the machine could be used in future university projects as well as how it could be improved. The paper begins by defining low-velocity impacts and describing the factors that influence them. The second topic is the iterative design process involved with making an impact machine so that accurate results can be obtained. In the third section, some of the challenges and opportunities associated with the concept of low velocity impacts with a variety of tests conducted on the machine and with different materials. A summary of the design and results of the study is presented at the end of the paper, followed by some suggestions for further research and improvements that could be made
Business, Belonging, and Culture Within the Realms of Culturally Based Fraternal Organizations (CBFO)
Get PDFThis qualitative research study aimed to explore the membership experience of culturally based
Greek organizations in relation to childhood upbringing and background. Through in-depth
interviews with collegiate and alumni members, the study sought to understand what factors
from childhood and cultural background motivates individuals to join a Culturally Based
Fraternal Organizations (CBFO) and examines the themes of belonging and business within the
overall CBFO membership experience. Information from this study is beneficial to understand
the needs, motivations, and values of current members and future members. Leadership from
national to local CBFOs can utilize the insight gained from this study to examine how
organization’s operation and programming can make improvements to cater to the needs of their
targeted demographic
A Comparison of the Ivan Galamian and Rachel Barton Pine editions of the Sonata No. 3 in C Major for Solo Violin by Johann Sebastian Bach, BWV 1005
Get PDFStudy of the Sonatas and Partitas by Johann Sebastian Bach (1685—1750) is an
inevitable avenue of the violinist’s artistic journey. The most commonly studied version of the
Sonatas and Partitas is the edition published in 1971 by the renowned 20th century pedagogue
Ivan Galamian. In recent years, interest and observance of historical performance practice has
increased. As such, new editions and treatises of the Sonatas and Partitas have been published
featuring historically-informed interpretations, including one such edition by Rachel Barton Pine
in 2017.
Of the Sonatas and Partitas, the Sonata No. 3 in C Major BWV 1005 tends to be
considered as one of the most challenging of the set. This document will therefore compare the
classic fingerings and bowings of the Ivan Galamian and the historically-informed approach of
Rachel Barton Pine of the Sonata No. 3 in C Major. There are two major factors that lead to the
differences. First, violinists of the early 18th century tended to utilize first position while
contemporary violinists use a wider variety of positions. Second, bowing styles were better
suited to a different bow, as evidenced by the bowings included in the autograph manuscript. The
Pine edition tends to remain closer to the bowings indicated in the autograph manuscript, where
the Galamian edition makes a number of changes that better suit the modern bow. The fingerings
and bowings are the chosen criteria for comparison as they account for the two most significant
areas of editing that are found in both editions.
Both editions offer unique and illuminating insight, which merits in-depth study. Ideally,
a violinist would adopt ideas from both editions (and styles) in forming their own interpretations
of the Sonata No. 3 in C Major, BWV 1005
The Impact of Titanium Dioxide Nanoparticles on the Spoilage Bacterial Growth on Spinach Leaves
Get PDFNanoparticles are increasingly being considered for various agricultural applications, ranging from nano-based fertilizers to nano-pesticides that can easily attach to the produce. This work aspires to isolate spoilage bacteria from spinach leaves, determine the surface electrodynamic energies of bacteria isolates, evaluate the impact of nanoparticles on bacterial attachment from leafy vegetables, and determine the changes in Lifshitz-van der Waals and Lewis Acid/Base interfacial forces of bacteria in the surface with and without the presence of nanoparticles. It was hypothesized that titanium dioxide reduces the growth of spoilage bacteria on spinach leaves. The methods were divided into six sections: bacterial growth, isolating bacterial consortiums, contact angle measurements, xDLVO model, bacterial growth with the presence of titanium dioxide, and statistical analysis. Spinach spoilage took 35 days to form; LB media (Lysogeny broth) was used then for bacterial growth as the most recognized bacteria found was likely to be Erwinia species.
It was found that the addition of high titanium dioxide concentrations resulted in a decreased number of colony-forming units. Still, low titanium dioxide concentrations showed no statistical difference from bare spinach leaves. The Gibbs free energies of attachment for both Lifshitz-van der Waals and Lewis acid-base interactions were calculated to be negative for Erwinia with spinach leaves but positive for Erwinia with titanium dioxide. Because negative free energies correspond to a favorable interfacial thermodynamic interaction, and positive free energies correspond to an unfavorable interaction, this difference may partially explain the different observed spoilage behaviors in the absence and presence of titanium dioxide
Correlation between Perceived Emotional Support and Satisfying Interpersonal Communication: Technology Enabled and In-Person
Get PDFIn stark contrast to In-Person Communication (IPC), Technology Enabled Communication (TEC) presents challenges for interactions due to constraints on the transmission of social cues. This is hugely problematic as TEC increases the likelihood that messages will not be interpreted true to the meaning in which the sender intends. Despite the variety of ways individuals are connected through TEC, it seems that with missing social cues and modalities of communication, there is an overall sacrifice to the full potential of interactions. Instead of hearing and seeing the other, a text may substitute an impulse for communication at the cost of a substantial amount of unrealized social cues. Because the Mentalizing System (MS) and Mirror Neuron Systems (MNS) are central to participating in social interactions, the richest setting for having the ability to anticipate others’ intentions through gestural communication, imitation and empathy appears to take place in the context of IPC, with face-to-face interactions. Ultimately, well-being is impacted by how an individual uses TEC. As TEC communication with the identified support person increased, satisfaction with life scores decreased. As anticipated, however, IPC was shown to have a significant negative association with relationship stress in that higher rates of IPC were related to lower rates of stress within the relationship with the identified support person.
keywords: Communication Satisfaction, Emotional Support, In-Person Communication, Technology Enabled Communication, Mirror Neurons, Mentalizing Syste
Stabilization of drilling foams using nanoparticles
Get PDFUnderbalanced drilling often uses foam because of its superior hole-cleaning capacity, low density, and reduced liquid requirements. However, it must be stable under borehole conditions to function as a drilling fluid. When the foam is unstable, it loses its viscosity, causing the liquid to drain and create slugging flow, causing a temporary overbalance that may damage the formation. This study aims to improve aqueous foam stability using nanoparticles with unique surface properties.
Nanoparticles possess unique properties due to their small size and high specific surface area. Furthermore, their surfaces can be modified to display desired properties. As part of this study, bare (NS1) and functionalized silicon oxide nanoparticles (NS2, and NS3) were studied to improve the stability of aqueous foams. A foam circulating flow loop with horizontal pipe viscometers and a vertical drainage testing cell was used to create foam and analyze its characteristics. Foams with varying nanoparticle concentrations (1 to 3% by wt.) and foam qualities (40 to 60%) were generated at 1000 psi. The rheology and stability of these materials were then investigated. To assess the drainage, the hydrostatic pressure distribution was measured as a function of time after a fully generated foam was trapped in a vertical test cell.
A significant increase in apparent viscosity and reduction in liquid drainage was observed when the baseline foam quality (in-situ gas volumetric concentration) was raised from 40% to 60%. Similar changes in property were also observed in nanoparticles containing foam. In addition to this, experiments showed that nanoparticles have an impact on the properties of foams. With the addition of nanoparticles, foams became more viscous and stable. The type (coating) of nanoparticles also influences their effectiveness. For instance, amino-functionalized silica nanoparticles (NS2) provide better foam stability than regular nanoparticles (NS1) and nanoparticles treated with silane (NS3)
The role of personality in television streaming-related motivations and parasocial behaviors
Get PDFThis paper explores the relationship between personality traits and motivations for using streaming video on demand (SVOD) services. The study aims to fill a gap in the literature on the individual differences and uses and gratifications of SVOD consumption by integrating the HEXACO personality factors and facets of motivations for using SVOD services. The study finds that all HEXACO factors are significant predictors of SVOD motivations overall, with honesty-humility, emotionality, extraversion, and agreeableness predicting the majority of the 16 SVOD motivations. The findings provide fresh information about how people perceive, are motivated by, and intend to utilize internet streaming technologies to view recorded movies, television shows, and live broadcasts, and identify if people with certain personality traits are more or less likely to use SVOD for certain motivations. The study contributes to the body of academic literature on the streaming industry, which has become increasingly split off into niche services with narrow-casted content