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Landsat Thematic Mapper Data Set
No full textLandsat 5 TM (Thematic Mapper) data set was collected in 7 bands from the late 1980's to early 1990's, centered around 1990
An Exposition of User Privacy on the Web: Fingerprinting and Tracking
No full textBrowser fingerprinting techniques are commonly used by websites and online services to track users for various purposes, such as targeted advertising, user authentication, and fraud detection. These techniques aim to uniquely identify web browsers by utilizing attributes such as browser vendor and version, plugins and extensions, canvas rendering, fonts, performance characteristics, platform, clock skews, and screen resolutions, collected through JavaScript APIs and HTTP headers. However, with the enactment of data protection regulations like General Data Protection Regulation (GDPR), California Consumer Privacy Act (CCPA), and General Data Protection Law (LGPD), which require user consent for data collection and processing, there has been a growing emphasis on safeguarding user privacy. Despite these regulations, research has shown that online services often resort to deceptive tactics, lack opt-out options, or have complex user interfaces for consent. Even when users exercise their rights, data mishandling and weak authentication mechanisms may lead to unauthorized data access. Regulators have mainly focused on auditing compliance of well-known corporations, but there is a lack of systematic mechanisms to detect infringements at scale. Previous research has largely ignored cases where compliance is conveyed correctly but online services fail to comply, raising concerns about their commitment to user privacy.
The objective of this dissertation research is to contribute to the understanding of modern privacy issues on the internet. The study is organized into four main parts: (1) design of attacks to breach privacy, (2) design of privacy defense tools, (3) measurement of privacy compliance, and (4) measurement of browser fingerprinting in targeting and tracking. The first part involves the de-velopment of an attack called ���Gummy Browser��� that targets fingerprint-based tracking algorithms. This attack allows a malicious actor to impersonate a victim and view victim-specific (potentially sensitive) ads, thereby gaining more information about the victim. Additionally, a privacy defense method based on Canvas Fingerprinting was devised to defend against fingerprinting attacks. In addition, the research includes an evaluation of privacy compliance by investigating the relation-ships among various roles on the internet, including consent management platforms, advertisers, websites, and tracking methods such as cookies. Finally, the measurement was undertaken to assess the utilization of browser fingerprinting in the realms of targeting and tracking
Examining Carbon Emission Patterns in Different Stages of National Economic Development
No full textCountries undergo development at different times and rates, raising the question of whether more developed countries will simply outsource their demand for pollution-intensive goods to countries in lower stages of development. Using regression models for both linear OLS and the Environmental Kuznets Curve (EKC) models, this paper analyzes the relationship between aggregate carbon dioxide emissions and GDP per capita on a country-year level in the time period 1995-2020 to examine the differences in emissions production patterns for countries in different stages of development and determine whether countries developing later in time experience advantage or disadvantage in lowering environmental pollution rates. The two different regression models are used in order to determine whether emissions continually increase or if they reach a point when they start to decrease, accounting for controls that may affect development and pollution levels; regressions are applied to the entire dataset to assess global trends of carbon pollution, as well as subgroups (low, lower-middle, upper-middle, and high) based on average income per capita in 1995 as a proxy to assess emission patterns in different stages of development. The study finds that the EKC hypothesis is generally supported in trends for low-income and lower-middle income countries, as GDP per capita is correlated with CO2 emissions in these subgroups. However, the correlation becomes less significant as average income per capita increases, with both the upper-middle-income and high-income groups showing a lack of statistical significance for GDP per capita on emissions. In high-income countries, growth of CO2 emissions is associated more strongly with growth of population and average life expectancy rather than GDP per capita growth. EKC model calculations for GDP per capita turning points are 16677.02 for the lower-middle-income group, and 53626.94. However, the GDP coefficient of the EKC does not seems to hold statistical significance for the upper-middle and high-income groups. Additionally, the passage of time correlates with emissions decrease in all subgroups, and the continuously-decreasing GDP per capita turning points for CO2 emissions in subgroups serves as evidence of the latecomer���s advantage
Investigation of the Inverse Fracture Occurrence in Drop Weight Tear Tests of X65 Q&T Pipeline Steels Under Impact Loading
No full textAbnormal fracture appearance (AFA) in Drop Weight Tear Testing (DWTT) constitute substantial matters of concern, particularly in sectors such as pipeline construction, where material integrity holds paramount importance for ensuring safety and reliability. AFA in DWTT refers to unexpected and non-standard patterns of material fracture during impact testing, such as reverse fractures or irregular fracture paths. The statistical nature of this occurrence requires a deterministic approach to resolve it in the form of reducing its likelihood during experiments. In order to set a strategy, a phenomenological continuum level model is developed to account for the ductile-brittle transition behavior of X65 Q&T and strain rate effect, which will provide a platform to conduct parametric studies on boundary conditions defining the recurrence of reverse fracture morphology. The selected material exhibits strain rate sensitivity and discontinuous yield stress region (L��ders band) at room and low temperatures, which diminishes as temperature decreases in about 15% of plastic strain at yielding. Moreover, the Charpy impact test indicates that the 85% shear area transition temperature is ��� 105��C, while reverse fracture appears at higher temperatures in the range of ���15��C to ���45��C. This transition temperature shift is allegedly attributed to the compressive pre-strain induced by the impact hammer in the back of the samples, which damages the region before the propagating crack reaches. In this thesis work, a well-sound engineering model is proposed and adjusted for a given DWTT condition, in which AFA takes place, to numerically capture salient features such as ductile-brittle fracture transition (DBT). DBT is characterized by having a crack propagating initially ductile with a flat surface perpendicular to the opening stresses which eventually turns into a cleavage fracture. Using this model various configurations of the experimental setup (boundary conditions) are explored with the aim at to reduce the likelihood of AFA. It turns out that by varying boundary conditions a significant reduction of reverse fracture morphology is observed indicating that by controlling the experimental setup features such as hammer shape, surface roughness, and specimen geometry the occurrence of this phenomenon can be controlled
Transcriptomic Alterations to Renal CD31+/Podoplanin+ Cells in Hypertension
No full textHypertension (HTN) is a condition of chronically elevated blood pressure (BP) and the most common risk factor for severe cardiovascular disease. HTN can directly lead to renal damage, immune cell activation, and inflammation. This vicious cycle contributes to a progressive decline in renal function and further elevation in BP. Since lymphatic vessels are responsible for removing interstitial immune cells and resolving inflammation, previous studies examined the role of renal lymphatic endothelial cells (LECs) in HTN and revealed that renal LECs expand in number and coverage in multiple murine HTN models. Additionally, augmentation of renal lymphangiogenesis through genetic or therapeutic means can reduce or prevent a rise in BP, as well as reduce the number of pro-inflammatory immune cells in the kidney. Single-cell RNA sequencing (scRNAseq) was utilized to determine the effects of angiotensin II-induced HTN (A2HTN) and salt sensitive HTN (SSHTN) on renal CD31+/podoplanin+ cells. LECs, myeloid immune cells (MICs), and a novel stem cell-like population dubbed support cells (SCs) were identified based on their distinct gene expression profiles and existing datasets. Using differential gene expression, regulon activity, and gene set enrichment analyses, changes in LECs and SCs in control and HTN samples were evaluated. Renal LECs underwent a marked inflammatory response due to HTN, particularly in terms of genes, pathways, and regulons related to inflammation-driven proliferation and immune checkpoint activity. SCs, which display both stem cell characteristics and expression of marker genes for multiple distinct nephron cell types, downregulated genes related to suppression of stem cell activity, upregulated genes involved in stem cell regeneration and proliferation, and upregulated fewer inflammation-related genes compared to LECs in HTN. Potential signaling interactions between LECs, SCs, and MICs were identified, including differential signaling activity between control and HTN samples in LECs and SCs. Tgfb1 had significant, consistent effects in each cell type in the control samples while the HTN samples had a higher quantity of enriched downstream targets in LECs and SCs. Future work will be needed to verify the findings presented here and to determine how they can best be manipulated therapeutically to help reduce BP and renal damage and inflammation