Ball and socket joints provide accurate biaxial gimbal

Ball-and-socket joints are used to connect two rotating inputs to orthogonally pivoted outputs. This provides an accurate biaxial gimbal which will operate in continuous motion without backlash

The Applicability of Gamma-Ray Spectrometry within Soil Science

Detailed spatial soil information is needed to better address environmental challenges across regional, national, and global scales. In the U.S., point-scale soil data are available to provide information on chemical and physical properties of soil as well as polygons where soils occur on the landscape. However, the soil data suffer from several shortcomings in terms of internal consistency as well as an inaccurate portrayal of soil variability. Passive aerial gamma-ray radiometrics is a tool that has been successfully used to represent soil variation because it may represent changes in parent materials. Legacy aerial gamma radiometric data is currently available across the United States but as such, has not been compared with soil properties. Therefore, the overall objective of this study was to assess the applicability of aerial gamma-ray spectrometry for the application of mapping soil properties associated across the U.S. Gamma radiometrics were compared with legacy soil samples across the United States. The quality of the initial aerial gamma-ray surveys were assessed by first comparing soil properties against with proximal gamma-ray surveys, followed by proximal and aerial radiometric comparisons within different parent materials in the state of Texas. After determining that aerial gamma radiometric variation is best understood in terms of physiography, results indicated weak to moderately significant relationships between the two datasets for soil properties such as soil texture and cation-exchange capacity. Results support the conclusion that the soil sampling locations as well as the poor spatial resolution of the legacy gridded gamma radiometric data contribute to low correlation coefficients. Proximal survey results indicate that aerial gamma-ray spatial patterns are related with soil properties such as texture and inorganic carbon within different parent materials. Results also indicate that poor geo-spatial positioning of aerial surveys drives the decrease in quality of correlations with soil data on the ground. Aerial gamma-ray spectrometry has utility for mapping soil properties, but consideration must first be given toward parent material and physiography type. Future studies should consider understanding aerial gamma radiometrics in the United States by surveying additional parent materials not present in this study

Wave speeds and Green’s tensors for shear wave propagation in incompressible, hyperelastic materials with uniaxial stretch

Assessing elastic material properties from shear wave propagation following an acoustic radiation force impulse (ARFI) excitation is difficult in anisotropic materials because of the complex relations among the propagation direction, shear wave polarizations, and material symmetries. In this paper, we describe a method to calculate shear wave signals using Green's tensor methods in an incompressible, hyperelastic material with uniaxial stretch. Phase and group velocities are determined for SH and SV propagation modes as a function of stretch by constructing the equation of motion from the Cauchy stress tensor determined from the strain energy density. The Green's tensor is expressed as the sum of contributions from the SH and SV propagation modes with the SH contribution determined using a closed-form expression and the SV contribution determined by numerical integration. Results are presented for a Mooney-Rivlin material model with a tall Gaussian excitation similar to an ARFI excitation. For an experimental configuration with a tilted material symmetry axis, results show that shear wave signals exhibit complex structures such as shear splitting that are characteristic of both the SH and SV propagation modes

Модернизация органов государственной власти в европейском союзе и российской федерации: взгляд молодежи

Цель этой статьи – оценить, является ли модель идеальной организаци

Quantum Concentration Inequalities

We establish Transportation Cost Inequalities (TCIs) with respect to the quantum Wasserstein distance by introducing quantum extensions of well-known classical methods: First, we generalize the Dobrushin uniqueness condition to prove that Gibbs states of 1D commuting Hamiltonians satisfy a TCI at any positive temperature and provide conditions under which this first result can be extended to non-commuting Hamiltonians. Next, using a non-commutative version of Ollivier’s coarse Ricci curvature, we prove that high temperature Gibbs states of commuting Hamiltonians on arbitrary hypergraphs H= (V, E) satisfy a TCI with constant scaling as O(|V|). Third, we argue that the temperature range for which the TCI holds can be enlarged by relating it to recently established modified logarithmic Sobolev inequalities. Fourth, we prove that the inequality still holds for fixed points of arbitrary reversible local quantum Markov semigroups on regular lattices, albeit with slightly worsened constants, under a seemingly weaker condition of local indistinguishability of the fixed points. Finally, we use our framework to prove Gaussian concentration bounds for the distribution of eigenvalues of quasi-local observables and argue the usefulness of the TCI in proving the equivalence of the canonical and microcanonical ensembles and an exponential improvement over the weak Eigenstate Thermalization Hypothesis

A mudança organizacional e as estratégias utilizadas para implementação do modelo de gestão por processo: o caso EMATER-PR

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção

Laboratório virtual de imunologia-brucelose

Orientador: Ida Cristina GubertCo-orientador: Luiz Felipe CaronRemy LessnauMonografia(Bacharelado) - Universidade Federal do Paraná. Setor de Ciencias Biológicas. Curso de Graduaçao em Ciencias Biológica

Dynamics of Particle Migration in Confined ViscoElastic Poiseuille Flows

Particles migrate in the transverse direction of the flow due to the existence of normal stress anisotropy in weakly viscoelastic liquids. We test the ability of theoretical predictions to predict the transverse velocity migration of particles in a confined Poiseuille flow according to the viscoelastic constitutive parameters of dilute polymers solutions. Firstly, we carefully characterize the viscoelastic properties of two families of dilute polymer solutions at various concentrations using shear rheometry and capillary breakup experiments. Secondly, we develop a specific 3D particle tracking velocimetry method to measure with a high accuracy the dynamics of particles focusing in flow for Weissenberg numbers Wi ranging from $10^{-2}$ to $10^{-1}$ and particle confinement $\beta$ of 0.1 and 0.2. The results show unambiguously that the migration velocity scales as $\text{Wi}\beta^2$, as expected theoretically for weakly elastic flows of an Oldroyd-B liquid. We conclude that classic constitutive viscoelastic laws are relevant to predict particle migration in dilute polymer solutions whereas detailed analysis of our results reveals that theoretical models overestimate by a few tenth the efficiency of particle focusing.Comment: 24 pages, 7 figure

Measuring elastic nonlinearity in a soft solid using a tilted acoustic radiation force for shear wave excitation

Excitation of multiple wave modes using shear wave elastography can result in additional information about the tissue's material characteristics and, potentially, improve disease diagnosis. Theoretically, tilting the acoustic radiation force excitation axis with respect to the material's symmetry axis should excite several wave modes in the material. In this work, we have experimentally demonstrated proof of concept in a uniaxially stretched phantom, while increasing the stretch level. Tilted acoustic radiation force experiments showed a clearly visible second wave mode across the stretch direction for larger stretches (>160%)