Boundary controllability of incompressible Euler fluids with Boussinesq heat effects

2015 ◽  
Vol 28 (1) ◽  
Author(s):  
Enrique Fernández-Cara ◽  
Maurício C. Santos ◽  
Diego A. Souza
Keyword(s):  
Boundary Controllability ◽  
Heat Effects ◽  
Incompressible Euler ◽  
Euler Fluids

Incompressible Euler Fluids

2009 ◽  
pp. 197-232
Author(s):  
C. Truesdell ◽  
K. R. Rajagopal
Keyword(s):  
Incompressible Euler ◽  
Euler Fluids

Neural and sociocultural mediators of ethnic differences in pain

2020 ◽  
Author(s):  
EAR Losin ◽  
CW Woo ◽  
NA Medina ◽  
JR Andrews-Hanna ◽  
Hedwig Eisenbarth ◽  
...  
Keyword(s):  
African Americans ◽  
Ethnic Differences ◽  
Nociceptive Pain ◽  
Common Belief ◽  
Pain Mechanisms ◽  
Thermal Pain ◽  
Heat Effects ◽  
Pain Report ◽  
And Gender ◽  
Ethnicity And Gender

© 2020, The Author(s), under exclusive licence to Springer Nature Limited. Understanding ethnic differences in pain is important for addressing disparities in pain care. A common belief is that African Americans are hyposensitive to pain compared to Whites, but African Americans show increased pain sensitivity in clinical and laboratory settings. The neurobiological mechanisms underlying these differences are unknown. We studied an ethnicity- and gender-balanced sample of African Americans, Hispanics and non-Hispanic Whites using functional magnetic resonance imaging during thermal pain. Higher pain report in African Americans was mediated by discrimination and increased frontostriatal circuit activations associated with pain rating, discrimination, experimenter trust and extranociceptive aspects of pain elsewhere. In contrast, the neurologic pain signature, a neuromarker sensitive and specific to nociceptive pain, mediated painful heat effects on pain report largely similarly in African American and other groups. Findings identify a brain basis for higher pain in African Americans related to interpersonal context and extranociceptive central pain mechanisms and suggest that nociceptive pain processing may be similar across ethnicities.

scholarly journals Thin-Film Processing of Polypropylene and Polystyrene Sheets by a Continuous Wave CO2 Laser with the Cu Cooling Base

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1448
Author(s):  
Nobukazu Kameyama ◽  
Hiroki Yoshida ◽  
Hitoshi Fukagawa ◽  
Kotaro Yamada ◽  
Mitsutaka Fukuda
Keyword(s):  
Thin Film ◽  
Co2 Laser ◽  
Continuous Wave ◽  
Cw Laser ◽  
Heat Effects ◽  
Film Processing ◽  
Carbon Dioxide Co2 ◽  
A Minor ◽  
Residual Heat ◽  
Thin Film Processing

Carbon dioxide (CO2) laser is widely used in commercial and industrial fields to process various materials including polymers, most of which have high absorptivity in infrared spectrum. Thin-film processing by the continuous wave (CW) laser is difficult since polymers are deformed and damaged by the residual heat. We developed the new method to make polypropylene (PP) and polystyrene (PS) sheets thin. The sheets are pressed to a Cu base by extracting air between the sheets and the base during laser processing. It realizes to cut the sheets to around 50 µm thick with less heat effects on the backside which are inevitable for thermal processing using the CW laser. It is considered that the boundary between the sheets and the base is in thermal equilibrium and the base prevents the sheets from deforming to support the backside. The method is applicable to practical use since it does not need any complex controls and is easy to install to an existing equipment with a minor change of the stage.

scholarly journals Shock Structure and Relaxation in the Multi-Component Mixture of Euler Fluids

Symmetry ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 955
Author(s):  
Damir Madjarević ◽  
Milana Pavić-Čolić ◽  
Srboljub Simić
Keyword(s):  
Relaxation Times ◽  
Thermal Relaxation ◽  
Collision Operator ◽  
Weak Form ◽  
Shock Structure ◽  
Theory Approach ◽  
Component Mixture ◽  
Single Temperature ◽  
The Difference ◽  
Euler Fluids

The shock structure problem is studied for a multi-component mixture of Euler fluids described by the hyperbolic system of balance laws. The model is developed in the framework of extended thermodynamics. Thanks to the equivalence with the kinetic theory approach, phenomenological coefficients are computed from the linearized weak form of the collision operator. Shock structure is analyzed for a three-component mixture of polyatomic gases, and for various combinations of parameters of the model (Mach number, equilibrium concentrations and molecular mass ratios). The analysis revealed that three-component mixtures possess distinguishing features different from the binary ones, and that certain behavior may be attributed to polyatomic structure of the constituents. The multi-temperature model is compared with a single-temperature one, and the difference between the mean temperatures of the mixture are computed. Mechanical and thermal relaxation times are computed along the shock profiles, and revealed that the thermal ones are smaller in the case discussed in this study.

Reconstructing Terrestrial Environments Using Stable Isotopes in Fossil Teeth and Paleosol Carbonates

2012 ◽  
Vol 18 ◽  
pp. 167-194 ◽  
Author(s):  
Benjamin H. Passey
Keyword(s):  
Isotopic Composition ◽  
Soil Temperature ◽  
Carbon Isotopes ◽  
Oxygen Isotopes ◽  
Precipitation Amount ◽  
Radiative Heating ◽  
Mammal Species ◽  
Isotopic Compositions ◽  
Heat Effects ◽  
Oxygen Isotopic

Carbon isotopes in Neogene-age fossil teeth and paleosol carbonates are commonly interpreted in the context of past distributions of C3 and C4 vegetation. These two plant types have very different distributions in relation to climate and ecology, and provide a robust basis for reconstructing terrestrial paleoclimates and paleoenvironments during the Neogene. Carbon isotopes in pre-Neogene fossil teeth are usually interpreted in the context of changes in the δ13C value of atmospheric CO2, and variable climate-dependent carbon-isotope discrimination in C3 plants. Carbon isotopes in pre-Neogene soil carbonates can be used to estimate past levels of atmospheric CO2. Oxygen isotopes in fossil teeth and paleosol carbonates primarily are influenced by the oxygen isotopic compositions of ancient rainfall and surface waters. The oxygen isotopic composition of rainfall is has a complex, but tractable, relationship with climate, and variably relates to temperature, elevation, precipitation amount, and other factors. Mammal species that rely on moisture in dietary plant tissues to satisfy their water requirements (rather than surface drinking water) may have oxygen isotopic compositions that track aridity. Thus, oxygen isotopes of fossil mammals can place broad constraints on paleoaridity. Carbonate clumped isotope thermometry allows for reconstruction of soil temperatures at the time of pedogenic carbonate mineralization. The method is unique because it is the only thermodynamically based isotopic paleothermometer that does not require assumptions about the isotopic composition of the fluid in which the archive mineral formed. Soil temperature reflects a complex interplay of air temperature, solar radiative heating, latent heat effects, soil thermal diffusivity, and seasonal variations of these parameters. Because plants and most animals live in and/or near the soil, soil temperature is an important aspect of terrestrial (paleo)climate.

scholarly journals Circulation and Energy Theorem Preserving Stochastic Fluids

2019 ◽  
Vol 150 (6) ◽  
pp. 2776-2814 ◽  
Author(s):  
Theodore D. Drivas ◽  
Darryl D. Holm
Keyword(s):  
Variational Principle ◽  
Energy Conservation ◽  
Euler Equations ◽  
Navier Stokes ◽  
Fluid Models ◽  
Smooth Solutions ◽  
Stochastic Fluid Models ◽  
Natural Extensions ◽  
Stochastic Fluid ◽  
Incompressible Euler

AbstractSmooth solutions of the incompressible Euler equations are characterized by the property that circulation around material loops is conserved. This is the Kelvin theorem. Likewise, smooth solutions of Navier–Stokes are characterized by a generalized Kelvin's theorem, introduced by Constantin–Iyer (2008). In this note, we introduce a class of stochastic fluid equations, whose smooth solutions are characterized by natural extensions of the Kelvin theorems of their deterministic counterparts, which hold along certain noisy flows. These equations are called the stochastic Euler–Poincaré and stochastic Navier–Stokes–Poincaré equations respectively. The stochastic Euler–Poincaré equations were previously derived from a stochastic variational principle by Holm (2015), which we briefly review. Solutions of these equations do not obey pathwise energy conservation/dissipation in general. In contrast, we also discuss a class of stochastic fluid models, solutions of which possess energy theorems but do not, in general, preserve circulation theorems.

Sign in / Sign up

Export Citation Format

Share Document