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As a team of eight scholars at the University of Texas, we collaborate to research issues that directly focus on the development, training, and experiences of anti-racist and social justice leaders in urban secondary schools. Each of us considered a personal event, or series of events, that significantly influenced our thinking about social justice. We share experiences of personal and institutional racism, and reflect on how these experiences continue to shape our awareness of race. Our perspectives capture how issues of race and racial discrimination persist in a status quo educational system and how past experiences directly influence our work.

This book provides a deeper understanding of what it means to promote social justice and equity work in schools and communities around the world. Throughout this book, narratives describe how authors continue to reshape the agenda for educational reform. They remind us of the significance meaningful relationships play in promoting and sustaining reform efforts that address the injustices vulnerable populations face in school communities. Their voices represent the need for engaging with obstacles and barriers and a resistant world through a web of relationships, an intersubjective reality (see Ayers, 1996). As authors engaged in thinking about addressing injustices, they describe how their thoughts transformed into actions moving beyond, breaking through institutional structures, attempting to rebuild and make sense of their own situations (see Dewey, 1938).

The purpose of this paper is to present a method for computing voltage spikes endured by the insulation of the first coils of high-temperature (HT°) synchronous machines fed by PWM inverters that deliver fast-fronted voltage pulses.

The transient state following each steep edge is computed by SPICE using the global high-frequency (HF) equivalent circuit of the motor winding. This equivalent circuit is automatically built using the proposed elementary coil model. Two inorganic HT° technologies are compared: the first one uses a round copper wire insulated by a thin ceramic layer and the second one is made with an anodized aluminum strip.

The winding made with an anodized aluminum strip, which has a higher turn-to-turn capacitance, yields a better voltage distribution between coils of the machine.

The elementary coil equivalent circuit is computed from impedance measurements performed on an elementary coil. Another starting point could be developed with an FE analysis to determine the parameters of the HF equivalent circuit, which would avoid the need for a prototype coil before the machine design.

For inorganic motors, the insulation layers have poorer electrical characteristics compared with standard organic ones. Therefore, the computation of voltage spikes distribution along the coils of each phase represents a major issue in the design of HT° machines.

The presented approach is a step toward the design of HT° (400-500°C) actuators fed by PWM inverters based on fast SiC electronic switches.

High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower breakdown voltages than the polymers used for insulating standard machines.

The voltage distribution between stator coils is computed with high-frequency (HF) equivalent circuits that consider the magnetic couplings and the stray capacitances. Two time scales are used for getting a fast computation of very short voltage spikes. For the first step, a medium time scale analysis is performed considering a simplified equivalent circuit made without any stray capacitance but with the full PWM pattern and the magnetic couplings. For the second step, a more detailed HF equivalent circuit computes voltage spikes during short critical time windows.

The computation made during the first step provides the critical time windows and the initial values of the state variables to the second one. The rise and fall time of the electronic switches have a minor influence on the maximum voltage stress. Conversely, the connection cable length and the common-mode capacitances have a large influence.

HF equivalent circuits cannot be used with random windings but only to formed coils that have a deterministic position of turns.

The proposed method can be used designing of HT° machine windings fed by PWM inverter and for improving the coils of standard machine used in aircraft’s low-pressure environments.

The influence of grounding system of the DC link is considered for computing the voltage spikes in the motor windings.

Because of the bioaccumulation effect, organophosphorus pesticides cause long-term damage to mammals, even at small concentrations. The ability to perturb the phospholipid bilayer structure as well as the overstimulation of cholinergic receptors makes them hazardous to humans. Therefore, there is a need for a quick and inexpensive detection of organophosphorus pesticides for agricultural and household use. As organophosphorus pesticides are acetylcholinesterase (AChE) inhibitors, biosensors using this mechanism hold a great promise to meet these requirements with a fraction of reagents and time used for measurement comparing to laboratory methods. This study aims to manufacture AChE-coated, screen-printed carbon electrodes applicable in such amperometric biosensors.

AChE enzyme, known for catalytic activity for the hydrolysis of acetylthiocholine (ATCh), could be used to obtain electrochemically active thiocholine from acetylthiocholine chloride in aqueous solutions. Using Malathion’s inhibitory effect towards AChE, pesticides’ presence can be detected by reduction of anodic oxidation peaks of thiocholine in cyclic voltammetry.

The conducted research proved that it is possible to detect pesticides using low-cost, simple-to-manufacture screen-printed graphite (GR) electrodes with an enzymatic (AChE) coating. Investigated electrodes displayed significant catalytic activity to the hydrolysis of ATCh. Owing to inhibition effect of the enzyme, amperometric response of the samples decreased in pesticide-spiked solution, allowing determination of organophosphorus pesticides.

Printed electronics has grown significantly in recent years as well as research focused on carbon-based nanocomposites. Yet, the utilization of carbon nanocomposites in screen-printed electronics is still considered a novelty in the market. Biosensors have proved useful not only in laboratory conditions but also in home applications, as glucometers are a superior solution for glucose determination for personal use. Although pesticides could be detected accurately using chromatography, spectroscopy, spectrometry or spectrophotometry, the market lacks low-cost, disposable solutions for pesticide detection applicable for household use. With biosensing techniques and electric paths screen-printed with GR or graphene nanocomposites, this preliminary research focuses on meeting these needs.

This paper explores the relationship between social movement protest, economic sabotage, state capitalism, the “Green Scare,” and public forms of political repression. Through a quantitative analysis of direct action activism highlighting the Earth Liberation Front and Animal Liberation Front, the discourse surrounding mechanisms of social change and their impact on state power and capitalist accumulation will be examined. The analyses examines the earth and animal liberation movements, utilizing a Marxist-anarchist lens to illustrate how these non-state actors provide powerful critiques of capital and the state. Specifically, the discussion examines how state-sanctioned violence against these movements represents a return to Foucauldian Monarchical power. A quantitative-qualitative history will be used to argue that the movements’ actions fail to qualify as “terrorism,” and to examine the performance of power between the radical left and the state. State repression demonstrates not only the capitalist allegiances between government and industry, but also a sense of capital’s desperation hoping to counter a movement that has produced demonstrable victories by the means of bankrupting and isolating corporations. The government is taking such unconstitutional measures as a “talk back” between the revolutionary potential of these movements’ ideology as well as the challenge they present to state capitalism.

The purpose of this study is to propose a new method to solve transient elasto-hydrodynamic lubrication (EHL) problem.

First, the steady-state EHL solution is modified so that the elastic deformation theory is combined with oil film stiffness distribution instead of steady-state Reynolds equation. Second, subsequent dynamic EHL procedure develops, recursively using transient distributed oil film stiffness and damping, where each time-marching solution is iteratively searched by ensuring both oil film force growth and elastic deformation update for each load increment.

This method increases calculation speed and provides both distributed EHL stiffness and damping for transient regimes.

This method is of interest for fast applications such as rolling bearings or gears.