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Effect of the Microstructure on the Corrosion Behavior of AlCuNiMn and AlCuNiMnSi high entropy alloys in a 3.5wt% NaCl solution
Get PDFIn this study, the AlCuNiMn and AlCuNiMnSi high entropy alloys (HEAs) are investigated to characterize the effect of Si addition and subsequent annealing treatments on the corrosion behavior in a 3.5wt% NaCl solution at room temperature. The microstructure evolution from the as-received condition and after annealing at 600°C, 800°C, and 1000°C for 24 hours in air is examined. The microstructural transformation of HEAs is extensively reported in the literature. However, its impact on the corrosion resistance of HEAs has not received the same attention. In this study, an increase in the annealing temperature of the base AlCuNiMn alloy improved the corrosion resistance due to element redistribution and homogenization of the microstructure. Annealing resulted in the appearance of new microconstituents with a higher resistance to corrosion compared to the alloy in the as-received condition. Introducing Si to the AlCuNiMn alloy system enhances the corrosion resistance. The addition of Si alters the morphology of the microstructure in three noticeable ways: 1) a redistribution of the other four elements, 2) the appearance of a new MnSi-rich microconstituent, and 3) a decrease in the size of voids. The results indicate that the AlCuNiMnSi alloy in the as-received condition is the superior alloy compared to the base AlCuNiMn alloy as it possesses the best corrosion resistance to the 3.5wt% NaCl solution. The presence of the Ni-rich microconstituent with small traces of Si slows the dissolution rate of the alloy. However, the phase fraction of Ni begins to dwindle then dissipates when the annealing temperature is increased to 800°C, leading to a slight increase in the corrosion rate
Resource Scarcity Caused By Environmental Changes: Driving Factor In Terrorism Attacks In Afghanistan, Pakistan, Syria
Get PDFClimate change, resource scarcity, and terrorist attacks are ever-growing crises that disproportionately impact different states. They are crises that can impact the stability and resilience of humanity in the following decades if they are not addressed and mitigated. This study addresses the impact of resource scarcity caused by climate change that can then serve as a driving force in terrorist attacks in climate-sensitive and conflict-prone states. The objective of this mixed-methods study is to identify the correlation between climate changes that lead to resource scarcity such as rainfall and surface temperatures with terrorist attacks when taking into consideration other demographic, economic, and political stressors, in the states of Afghanistan, Pakistan, and Syria. This study will obtain time series data between 1989 and 2019 from the following sources: World Bank, Freedom House, UN Database, and the University of Marylandâ??s Global Terrorism Database. The correlation between the independent variables of rainfall and surface temperatures and the number of total annual terrorist attacks per state will be evaluated and compared to the correlation that the control variables (stressors) will have on these documented terrorist attacks. Upon lagging all the variables observed and running a fixed-effects model on STATE to assess the relationship amongst variables, the results proved to be unsupported by the data. Such results were likely attributed to the overall sample size used and limitation of data. However, to further evaluate the trends that exist within the observed variables line charts were created. Such trends further indicated the need for future studies that integrate data from a larger sample size across a greater range of states
Automated Composition of Multivariable Scientific Workflows Considering Scientific Assumptions
Get PDFMany ground-breaking scientific experiments require the execution of multiple complex scientific computations. Thus, scientific workflows (i.e., a sequence of scientific computations) have received significant attention, more specifically, the automated composition of scientific workflows. Scientific workflows that repurpose data may have unique scientific assumptions that need to be considered when composing a workflow. Workflow composition tools have enabled a wider range of stakeholders (e.g., policymakers, the general public, and researchers) to create and execute workflows; however, domain expertise is still required for these tasks. The overarching goal of this work is to further improve the automatic composition of scientific workflows by validating if the scientific assumptions taken during the creation of a dataset are aligned with the scientific assumptions required to use these datasets for a specific scientific computation. This work aims to answer the following research questions: How can metadata and provenance be used to describe scientific assumptions of data consumed by scientific computations for the improvement of automated scientific workflow composition and repurposing of data? and to what extent can current Artificial Intelligence (AI) planning techniques with a heuristic function be used to formulate a scientific workflow that considers scientific assumptions in a hydrology domain? Our initial work focused on exploring automatic workflow composition with components that require and produce multiple scientific variables for an abstract case study (i.e., domain-free) using graph traversal. In addition, a second case study was conducted for a real-world hydrology scenario, which provided us with insights into how scientific assumptions could be described to enable model-to-model integration. In both cases, abstract and real-world scenarios, we use domain-independent vocabulary to represent a workflow for interoperability between different workflow management systems. We extended existing and widely used ontologies and vocabularies for describing scientific assumptions that are used in the automated composition of workflows. In addition, we propose a heuristic function for optimizing the algorithm. Our work aims to support scientific decision-making by enabling a wider range of stakeholders (e.g., policymakers, the general public) to automatically generate scientific workflows leveraging additional domain knowledge captured in metadata that can be executed in frameworks compatible with the standard workflow language used in this work
Race, Severe Mental Illness, and Crime: An Intersectional Look into Stigma and Policy Implications
Get PDFCriminal behavior has been a long-discussed topic in the United States and often is tied to characteristics such as race and mental illness. The presumed connection between criminal behavior and being a member of a racial minority group or having a mental illness have been researched for years, however few researchers have sought to take an intersectional approach to investigate the unique experiences of people belonging to both groups in the criminal legal system. Using the lenses of attribution and intersectionality theories, the proposed studies sought to understand the effect of race that influences policy support of justice-involved people with mental illness using participants gathered from Amazonâ??s CloudResearch platform. The study found that participants were significantly more likely to support rehabilitative correctional policies as compared to punitive policies, no matter the vignette information they were shown. However, attitudes about these groups of people and the police drove money allocation patterns. Mutability of justice-involved people, attitudes towards mental illness and support of the Defund the Police movement were some of the most notable. Though, these patters were not always in the direction expected; individuals who were not supportive of the Defund the Police movement, but saw the Black, violent vignette were much more likely to allocate money to mental health services as compared to correctional facilities or the police. The results suggests that there may be an element of social desirability in the participants, or it may be a demonstration of people overcorrecting for historical biases against Black men. The results have implications for both policymakers and in research, including the need for further exploration into concern for minority groups in the context of the criminal justice system, and the identification of areas that would benefit from educational interventions to reduce the discrepancies that are currently seen in the criminal justice system and offer more fair and just treatment
Religiosity And Executive Compensation Tournaments
No full textThis paper examines the effect that local religiosity has on executive compensation tournaments. The main finding suggests that a higher degree of local religiosity significantly reduces the magnitude of executive compensation tournaments. Subsample analyses involving the majority religious group of Christianity show that a higher local presence of Protestants relative to Catholics and other non-religious population heightens the negative effect of community-level religiosity on the magnitude of executive compensation tournaments. Additional subsample analyses involving the minority religious denominations also show that the effect of overall community religiosity is not solely driven by the different sects within the Christian denomination. Minority religious denominations as a composite group also appear to have a reasonably strong influence on reducing the magnitude of executive compensation tournaments similar to the Christian denomination. The main findings hold across multiple robustness tests and suggest that community religiosity is an essential determinant of executive compensation tournaments\u27 magnitude. Overall, the study attests to the positive value implications of religiosity on the equitable and fair distribution of wealth and other organizational or institutional resources
Sulfonated Polyethersulfone Membranes For Electrodialysis Desalination And The Influence Of Solvent Evaporation On Current Efficiency, Salinity Reduction, And Permselectivity
Get PDFThe high cost of ion exchange membranes significantly limits the public application of electrodialysis. The research of novel, inexpensive ion exchange membranes is essential to developing and applying electrodialysis desalination technology. This research focuses on fabricating cation exchange membranes with polyethersulfone (PES) and sulfonated PES (sPES) for water treatment. N-Methyl-2-Pyrrolidone (NMP) was used as an organic solvent to dissolve PES. After different solvent evaporation times were optimized from 0 hr to 24 hr, those membranes were formed through the phase inversion technique. The performance results show that the PES membranes performed the best when the solvent evaporated at 3 hr, while sPES membranes performed the best when the solvent evaporated within 1 hr. The electrodialysis (ED) test results were evaluated with different running conditions such as voltages, flow velocities, and feed solutions. LabVIEW software was used to collect data, including voltage, current, conductivity, etc. Compared with commercial Neosepta cation exchange membranes under the same test conditions, the salinity reduction rates performance of fabricated PES and sPES membranes are approximately 40% and 60% of Neosepta commercial membranes, respectively. Finally, the two membrane combinations with fabricated PES and sPES membranes have a relative transport number (RTN) of SO4 2-/Cl- both around 0.1; this is probably due to the co-ion transport through fabricated CEMs. The developed membranes have great potential in cost-effective desalination to address the global water crisis
Understanding The Limits Of Deep Packet Inspection For Network Traffic Classification
Get PDFWe present our human network application labeling system that contributes a new level of distinction between the network traffic that should be labeled from the network traffic that should not be labeled. This distinction improves the label accuracy of the training data set produced from the human labeled data and will subsequently improve the performance of supervised machine learning classifiers used for network traffic classification. This system also allows for the human network user to label traffic, with little effort, in a manner consistent with normal network usage, i.e., no need for a contrived experiment. Lastly, we use human supplied ground truth network application labels to analyze the performance of deep packet inspection techniques, specifically the nDPI library
El Testimonio De Los Niños De El Parque: Discipline Practices And The Impact On Public High School Students
No full textWhat happens to our students when they do not complete their studies and drop out of school? Perhaps this question is probably not something that we reflect on as educators. This study seeks to amplify three studentsâ?? voices and explore their unique experiences and the challenges they faced after they did not complete their high school studies. The interviews that I conducted tell the story of three minority students from lower-income families. Their stories highlight the overall purpose of this study, which is how students who find themselves involved in disciplinary issues are pushed out of school. The interviews capture the lived experiences as well as the resilience of these individuals. My research question focuses on understanding the personal and systemic challenges that marginalized youth face and how they navigate and make sense of the obstacles in their daily lives. I used qualitative and Testimonio methodology involving semi-structured interviews. The studentsâ?? lives are similar in that they are affected by socio-economic disadvantages and racial and ethnic marginalization. The interview protocol was designed to offer a safe and respectful environment to ensure that the participants shared their stories and perspectives openly. These interviews provided a rich collection of narratives that revealed significant insights into the adversities faced by these students, such as discrimination, limited access to resources, and social exclusion. The findings from my study not only shed light on the needs and challenges of these kids but also highlight the need for the development of all-encompassing strategies and supportive policies that can support studentsâ?? well-being and provide opportunities for them to complete their studies at the secondary level. My research contributes to a broader understanding of the intersectionality of disadvantage and resilience, offering guidance to educators, policymakers, and community stakeholders to better support vulnerable populations
Resisting Relapse: Positive Identity and Empowerment for Youth on the Frontera
No full textThis contribution chronicles the incorporation of culturally connected theatrical work for young people to reinforce positive identity formation during the height of the pandemic by an institution of higher learning. An interactive website, with the rasquache-infused production of Cenicienta at the heart, was created and made accessible to the underrepresented youth of El Paso, Texas. The author offers that institutions of higher learning are responsible for serving their home communities and must produce work that reflects such service – even after the pandemic; the temptation to revert to pre-pandemic programming should be combated with a renewed focus on purpose over product