Heat flow increase following the rise of mantle isotherms and crustal thinning

Heat flow measurements in the western United States define a zone of high heat flow which coincides with the Basin and Range Province where extension has taken place recently. In this region, the average reduced heat flow is approx 30 mW sq. meters higher than in stable continental provinces; locally (e.g., Battle Mountain High), the heat flow anomaly can be more than 100 mW/sq meters above average. Estimates of the amount of extension range between 30% and 100% for the past 30 Ma. In the Colorado Plateau, which has been uplifted without major tectonic deformation, the heat flow is only slightly above average. Analytical calculations show that an abrupt change in heat flow at the base of the lithosphere 30 Ma ago would not affect the surface significantly. Uplift would proceed at a slow rate. A thermal perturbation at the base of a 40 km thick crust, however, would reach the surface faster and, after 30 Ma, the increase in surface heat flow would be about 75% of the amplitude of the heat flow anomaly. The number of volcanic rocks in the Basin and Range suggests that magma intrusions may provide an effective heat transfer mechanism. It can be show that if the source of the intrusions is at the base of the lithosphere, the response time will be much longer than 30 Ma, and most ot the heat transferred from the asthenosphere will be absorbed in the lithosphere

Induced Flow in Coaxial Rotor Systems

In coaxial rotor helicopter systems, both rotors of the helicopter spin in opposite directions on the same vertical axis, requiring the bottom rotor to spin faster with a higher blade pitch angle and the top rotor to spin slower with a lower blade pitch angle. This was proven by Peters and Seidel [1]. As both blades are spinning, there is an induced flow of air between the rotors. The solution of the potential flow equations shows that the flow induced by the upper rotor on the lower is related to the adjoint velocity above the rotors and the time delays in the system. Therefore, the model used to determine the effects of the inflow will have both velocity states and co-states with included time delays. The time delays result from the effects of the vortex shed by the upper rotor, causing the induced flow on the upper rotor to decay with time as the flow on the lower rotor increases with time while the vortex moves downward. After the vortex has moved past the lower rotor, it decays again with an added time delay that matches that of the time it took to move between the two rotors. The main objective of this study is to determine how the velocity co-states affect the time delays on the Bode Plots for the transfer functions between rotor inputs and induced velocity on the two rotors. The computer language MATLAB and complex arithmetic are utilized in conjunction with Fourier Transforms to predict how the air will flow between the rotors when they are coupled through blade-element theory

COVID Anxiety and Stress in Higher Ed (CASH)

Access the online Pressbooks version of this article here. College is a time of increased stress and anxiety. The current changes in attendance and methods of instruction due to COVID-19 have demonstrated even higher levels of stress, anxiety, and mental health issues. Tailoring interventions to the specific needs of a campus community has been proposed as an appropriate means to the current crisis. This study identifies the mental health needs of students at a rural college as they pertain to the effects of the pandemic. Questionnaires collected data from college students (N=33) at Athens State University, a rural university in north Alabama, to understand the effects of the COVID-19 pandemic on their mental health and well-being. Data obtained from the 58-question instrument were analyzed through quantitative and qualitative methods. Results Data revealed that 33/33 (100%) students indicated higher levels of anxiety and stress due to the outbreak. Stressors contributing to the increased anxiety, stress, and depressive symptoms included anticipated duration of the pandemic (31/33, 93.9%), stress of current financial situation (24/33, 72.7%), uncertainty of the future (31/33, 93.9%), decreased social interactions and sense of community with peers (29/33, 87.9%), concerns about the health of loved ones and self (33/33, 100%). Students described a high level of comfort in participation in a flexible learning environment (31/33, 93.9%). Students identified various coping mechanisms. The results of our study underscore the need for directed mental health interventions for college students and flexible platforms of study. Consideration of developing a flexible learning environment should be included as part of directed mental health interventions

Reconciling Pyroclastic Flow and Surge: the Multiphase Physics of Pyroclastic Density Currents.

Two end-member types of pyroclastic density current are commonly recognized: pyroclastic surges are dilute currents in which particles are carried in turbulent suspension and pyroclastic flows are highly concentrated flows. We provide scaling relations that unify these end-members and derive a segregation mechanism into basal concentrated flow and overriding dilute cloud based on the Stokes number (ST), the Stability factor (ET) and the Dense-Dilute condition (DD). We recognize five types of particle behaviors within a fluid eddy as a function of ST and ET : (1) particles sediment from the eddy, (2) particles are preferentially settled out during the downward motion of the eddy, but can be carried during its upward motion, (3) particles concentrate on the periphery of the eddy, (4) particles settling can be delayed or “fast-tracked” as a function of the eddy spatial distribution, and (5) particles remain homogeneously distributed within the eddy. We extend these concepts to a fully turbulent flow by using a prototype of kinetic energy distribution within a full eddy spectrum and demonstrate that the presence of different particle sizes leads to the density stratification of the current. This stratification may favor particle interactions in the basal part of the flow and DD determines whether the flow is dense or dilute. Using only intrinsic characteristics of the current, our model explains the discontinuous features between pyroclastic flows and surges while conserving the concept of a continuous spectrum of density currents

French Connection: The culture and politics of Frenchness in Australia, 1890-1914

This thesis is a cultural history of ideas about France and the French in Australia during the late-nineteenth and early-twentieth centuries. It explores the links between representations of France, and of the French, and the ways in which different groups of individuals, whether they were French migrants or Australian colonists, mobilised these representations in social life. Until recently, studies of the French presence in Australia have tended to encase French lives in an ethnic framework, linked primarily to a social history of migrants. Although this has rescued some of their stories for posterity, it has also tended to marginalise them from a broader national story. This project, in contrast, combines French and Australian private and public sources (memoirs, letters, newspapers and works of fiction, as well as official government archives) to examine the shifting relational significance of France, both for the Australian nation and for individuals who lived during a formative period in its history. Pitched in the liminal space between two countries’ records, the thesis demonstrates that the tensions that arose in the articulation of cultural difference between Australian colonists and French and francophone migrants are revealing of the complex and sometimes paradoxical expressions of Frenchness in the antipodes in the decades before the Great War. They show some of the processes at play in the on-going definition of Australian culture and character in the early Federation era and bring to light a range of political and personal meanings that France had in people’s lives. In underscoring the connections that the Australian colonies, and later the Australian nation, entertained with France, this work helps bring to light the global and transnational connections constitutive of Australian history and identity

Addressing Complexity in Laboratory Experiments: The Scaling of Dilute Multiphase Flows in Magmatic Systems.

The kinematic and dynamic scaling of dilute multiphase mixtures in magmatic systems is the only guarantee for the geological verisimilitude of laboratory experiments. We present scaling relations that can provide a more complete framework to scale dilute magmatic systems because they explicitly take into account the complexity caused by the feedback between particles (crystal, bubble, or pyroclast) and the continuous phase (liquid or gas). We consider three canonical igneous systems: magma chambers, volcanic plumes, and pyroclastic surges, and we provide estimates of the proposed scaling relations for published experiments on those systems. Dilute magmatic mixtures can display a range of distinct dynamical regimes that we characterize with a combination of average (Eulerian) properties and instantaneous (Lagrangian) variables. The Eulerian properties of the mixtures yield the Reynolds number (Re), which indicates the level of unsteadiness in the continuous phase. The Lagrangian acceleration of particles is a function of the viscous drag and gravity forces, and from these two forces are derived the Stokes number (ST) and the stability number (ΣT), two dimensionless numbers that describe the dynamic behavior of the particles within the mixture. The compilation of 17 experimental studies relevant for pyroclastic surges and volcanic plumes indicates that there is a need for experiments above the mixing transition (Re>104), and for scaling ST and ΣT. Among the particle dynamic regimes present in surges and plumes, some deserve special attention, such as the role of mesoscale structures on transport and sedimentary processes, or the consequences of the transition to turbulence on particle gathering and dispersal. The compilation of 7 experimental studies relevant to magma bodies indicates that in the laminar regime, crystals mostly follow the motion of the melt, and thus the physical state of the system can be approximated as single phase. In the transition to turbulence, magmas can feature spatially heterogeneous distributions of laminar regions and important velocity gradients. This heterogeneity has a strong potential for crystals sorting. In conclusion, the Re-ST-ΣT framework demonstrates that, despite numerous experimental studies on processes relevant to magmatic systems, some and perhaps most, geologically important parameter ranges still need to be addressed at the laboratory scale

MEMS 411: Soccer Robot

This design project was altered from the 2018 ASME Soccer Robot competition. Dr. Jackson Potter led a competition where groups built remote control robots to compete against each other in 1v1 matches based on a modified rule set from the initial 2018 competition

Numerical simulations of the mingling caused by a magma intruding a resident mush

Currently, our ability to interpret the mechanics of magma mingling and mixing is limited by an incomplete understanding of the modes of mixing across all melt fractions and compositions. Here, we present numerical simulations of the emplacement of crystal-free magma in crystal-rich reservoirs employing a computational fluid dynamics and discrete element method (CFD–DEM). We performed two runs corresponding to the emplacement of basalt into two end-member types of magmas mush (basaltic and dacitic). We found that the intruded volumes have similar shapes and are surrounded by a halo where the crystal volume fraction of the mush is lower. The dynamics of intruded melt are, however, different. Importantly, the mingling of the intruded and host materials starts after emplacement and consists in the incorporation of mush material into the intruded magma. Our findings imply that purely thermo-mechanical processes controlled by grain-scale dynamics are sufficient to explain fundamental aspects of recharge

Exile Vol. XI No. 1

FICTION By the Fire of the Chief by Peggy Schmidt 9-17 From the Diary of a Vanishing Man by Ed Brunner 19-29 Dialogue by Ken Booth 35-37 POETRY Johnny Joe by Bill West 6-7 Caterpillar by Barb Bergantz 17 Poem by Bonnie McCarthy 29 The Queen by Hugh Wilder 31 The Clown by Barb Bergantz 32 Poem by Gretchen Schenck 33 Treatise on Cosmology by P. M. Grout 37 Stimulus by Susan Sherwood 37 Depot by Susan Sherwood 39 GRAPHICS Pen and Ink by Dave Goodwin 7 Pen and Ink by Ramona Gibbs 8 Pen and Ink by Tod Riddell 18 Charcoal by Dave Goodwin 30 Woodcut by Parker Waite III 34 Woodcut by Lela Giles 3

A methodology for the capture and analysis of hybrid data: a case study of program debugging

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