U.S. Government and Politics in Principle and Practice: Democracy, Rights, Freedoms and Empire

This book is written for students early in college to provide a guide to the founding documents and structures of governance that form the United States political system. This book is called American Government and Politics in Principle and Practice because you will notice that what has been inscribed in law has not always been applied in practice-particularly for indigenous peoples, enslaved peoples, people of color, women, LGBTQIA+, people with disabilities, those formerly incarcerated, immigrants and the working class within U.S. society. In designing this book, we have two goals. First, we want you to know what the founding documents say and how our political institutions were formed. Second, and as important, we season the book with questions for you to investigate and learn concerning who has been excluded and who has benefited from the political structures of the United States. We will examine the contradictions and tensions that erupt, and how social movements have transformed our political landscape. We offer a range of questions/assignments that will allow you to help us keep this book up to date. You will read, across time, tensions between the federal and state governments, between individual and collective rights, between those with power and those without, and you will notice when and for whom rights have been protected by our government and when and for whom rights have been trampled. We will explore the historical context that informs significant political movements and structures of the present. This is history riddled with racism, xenophobia, sexism and imperialism, and also a vibrant history of struggle where groups of people imagine, fight for, and often achieve a more equitable society

A candidate fusion engineering material, WC-FeCr

A new candidate fusion engineering material, WC-FeCr, has been irradiated with He ions at 25 and 500 °C. Ions were injected at 6 keV to a dose of ~15 dpa and 50 at. % He, simulating direct helium injection from the plasma. The microstructural evolution was continuously characterised in situ using transmission electron microscopy. In the FeCr phase, a coarse array of 3–6 nm bubbles formed. In the WC, bubbles were less prominent and smaller (~2 nm). Spherical-cap bubbles formed at hetero-phase interfaces of tertiary precipitates, indicating that enhanced processing routes to minimise precipitation could further improve irradiation tolerance

Numerical investigation on the hydrodynamic performance of a 2D U-shaped Oscillating Water Column wave energy converter

The U-Oscillating Water Column (U-OWC) is a wave energy harvester exploiting the working principle of oscillating water columns for capturing and converting energy from sea waves. U-OWC devices can be integrated into a breakwater to enable wave energy extraction and provide shelter for port activities. In this work, a coupled Smoothed Particle Hydrodynamics (SPH) model was developed and applied to investigate the hydrodynamics of a U-OWC breakwater. The numerical model is validated against the experimental results over a range of regular wave conditions. An extensive campaign of computational tests is then carried out, studying the effects of geometrical parameters on the hydrodynamic performance and wave loading over the U-OWC breakwater. It shows that the geometrical parameters of the U-shape have a significant effect on the air pressure inside the chamber and the load phase difference between the two sides of the lip wall. The minimum load and maximum capture efficiency designs for U-OWC breakwaters cannot be satisfied geometrically at the same time. This demonstrates that it is necessary to consider comprehensively the structural reliability and hydrodynamic performance in the design and construction of a U-OWC breakwater

Learning and Controlling Silicon Dopant Transitions in Graphene using Scanning Transmission Electron Microscopy

We introduce a machine learning approach to determine the transition dynamics of silicon atoms on a single layer of carbon atoms, when stimulated by the electron beam of a scanning transmission electron microscope (STEM). Our method is data-centric, leveraging data collected on a STEM. The data samples are processed and filtered to produce symbolic representations, which we use to train a neural network to predict transition probabilities. These learned transition dynamics are then leveraged to guide a single silicon atom throughout the lattice to pre-determined target destinations. We present empirical analyses that demonstrate the efficacy and generality of our approach

Bearing signal separation enhancement with application to helicopter transmission system

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Bearing vibration signal separation is essential for fault detection of gearboxes, especially where the vibration is nonstationary, susceptible to background noise, and subjected to an arduous transmission path from the source to the receiver. This paper presents a methodology for improving fault detection via a series of vibration signal processing techniques, including signal separation, synchronous averaging (SA), spectral kurtosis (SK), and envelope analysis. These techniques have been tested on experimentally obtained vibration data acquired from the transmission system of a CS-29 Category A helicopter gearbox operating under different bearing damage conditions. Results showed successful enhancement of bearing fault detection on the second planetary stage of the gearbo