Analysis of the Effect of a Gyrotropic Anisotropy on the Phase Constant and Characteristic Impedance of a Shielded Microstrip Line

In this work, we present an analytical modeling of a highly complex medium-based shielded microstrip line. The study aims at a numerical evaluation of the characteristic impedance and the dispersion characteristics of the dominant hybrid mode in the microstrip line printed on an anisotropic medium. The newly considered complex anisotropy has a full 3×3 tensor form of permittivity and permeability. The study is based on the derivation of the Green's functions of the general complex-medium-based structure in the Fourier domain. The spectral Method of Moments (MoM) and the Galerkin's procedure are combined to solve the resulting homogeneous system of equations. The effect of the gyrotropic anisotropy on the phase constant and the characteristic impedance is particularly investigated. Original and interesting numerical results are obtained and discussed. Our results are found to be in good agreement with available isotropic case data reported in literature

Design of a sequential axial turbocharger for automotive application

Copyright © 2019 by the authors. In the last few years, the perspective of climate change, energy, competitiveness, and fuel consumption in the transportation sector has become one of the most significant public policy issues of our time. As different methods are being adapted into light-duty vehicles like engine downsizing, on the other hand, the increase in carbon emissions of heavy-duty trucks is becoming a major concern. Although previous researches have studied the methodology for selecting optimized turbocharger performance, still further investigation is needed to create a method for achieving the highest performance for a sequential axial turbocharger. Therefore, in this study, the design of a two-stage turbocharger system that consists of a radial turbine connected in series to an axial turbine is considered. The specific two-stage turbine was designed specifically and will be tested on a MAN 6.9 L diesel truck engine. With the engine already equipped with a radial type turbine, the newly designed two-stage turbine will be adapted to the engine to give more efficiency and power to it. Firstly, the modelling and simulation of the engine were done in Gt-Power, to achieve the same power and torque curves presented in the MAN engine specification sheet. Once that was achieved, the second task was to design and optimise a radial and axial turbine, which will form part of a two-stage system, through Computational Fluid Dynamics (CFD) analysis. Necessary data were gathered from the engine’s output conditions, for the ability to design the new turbo system. Lastly, the new turbine data were entered into the new two-stage turbo GT-Power model, and a comparison of the results was made. The CFD analysis, executed in ANSYS, for the radial turbine gave an 83.4% efficiency at 85,000 rpm, and for the axial turbine, the efficiency achieved was 81.74% at 78,500 rp

Analysis of the Combinatory Effect of Uniaxial Electrical and Magnetic Anisotropy on the Input Impedance and Mutual Coupling of a Printed Dipole Antenna

The main objective of this work is to investigate the combinatory effects of both uniaxial magnetic and electrical anisotropies on the input impedance, resonant length and the mutual coupling between two dipoles printed on an anisotropic grounded substrate. Three different configurations: broadside, collinear and echelon are considered for the coupling investigation. The study is based on the numerical solution of the integral equation using the method of moments through the mathematical derivation of the appropriate Green's functions in the spectral domain. In order to validate the computing method and evaluated Matlab? calculation code, numerical results are compared with available literature treating particular cases of uniaxial electrical anisotropy; good agreements are observed. New results of dipole structures printed on uniaxial magnetic anisotropic substrates are presented and discussed, with the investigation of the combined electrical and magnetic anisotropies effect on the input impedance and mutual coupling for different geometrical configurations. The combined uniaxial (electric and magnetic) anisotropies provide additional degrees of freedom for the input impedance control and coupling reduction

Understanding behaviour change in context: examining the role of midstream social marketing programmes

This research examines how midstream social marketing programmes that adopt a relational and community-based approach create opportunities for individuals to make incremental changes to health behaviour. Specifically, it applies Bourdieusian theory to explore how interactions between community healthcare workers (CHWs) and members of the public generate impetus for change and foster individual agency for improved health. Qualitative interviews were carried out with members of the public and CHWs engaged in a Smokefree homes and cars initiative. The findings suggest that although CHWs are challenged by resource constraints, their practices in working with individuals and families build trust and enable dialogue that bridges smoking-related health insight with home logics. These interactions can promote individual agency with a transformative effect through small changes to smoking-related dispositions, norms and practices. However, tensions with the habitus of other household members and other capital deficits can inhibit progress towards embedding new practices. The study concludes that interventions built upon community relationships show potential for addressing limitations of information-focused campaigns but there is a need to also respond to key social structures relating to the field of action for new health dispositions to become embedded in practice

Macrospin approximation and quantum effects in models for magnetization reversal

The thermal activation of magnetization reversal in magnetic nanoparticles is controlled by the anisotropy-energy barrier. Using perturbation theory, exact diagonalization and stability analysis of the ferromagnetic spin-s Heisenberg model with coupling or single-site anisotropy, we study the effects of quantum fluctuations on the height of the energy barrier. Opposed to the classical case, there is no critical anisotropy strength discriminating between reversal via coherent rotation and via nucleation/domain-wall propagation. Quantum fluctuations are seen to lower the barrier depending on the anisotropy strength, dimensionality and system size and shape. In the weak-anisotropy limit, a macrospin model is shown to emerge as the effective low-energy theory where the microscopic spins are tightly aligned due to the ferromagnetic exchange. The calculation provides explicit expressions for the anisotropy parameter of the effective macrospin. We find a reduction of the anisotropy-energy barrier as compared to the classical high spin-s limit.Comment: 10 pages, 11 figure

Analysis of Chiral and Achiral Medium Based Coplanar Waveguide Using Improved Full Generalized Exponential Matrix Technique

In this work, an analytical study of the electromagnetic propagation in a complex medium-based suspended three-layer coplanar waveguide (CPW) is carried out. The study aims at a numerical calculation of the dominant hybrid mode complex propagation constant in the CPW printed on a bianisotropic substrate. The herein considered bianisotropy is characterized by full 3×3 tensors of permittivity, permeability and magnetoelectric parameters. The study is based on the numerical derivation of the Green's functions of such a complex medium in the spectral domain. The study is carried out using the Full Generalized Exponential Matrix Technique based on matrix-shaped compact mathematical formulations. The Spectral Method of Moments (SMoM) and the Galerkin's procedure are used to solve the resulting homogeneous system of equations. The effect of the chiral and achiral bianisotropy on the complex propagation constant is particularly investigated. Good agreements with available data for an anisotropic-medium-based suspended CPW structure are achieved. Various cases of chiral and achiral bianisotropy have been investigated, and particularly, the effect on the dispersion characteristics is presented and compared with cases of isotropic and bianisotropic Tellegen media

Política de estabilização de renda para a agricultura familiar: uma análise de risco.

Os produtores familiares foram prejudicados pelas políticas de substituição de importações e de modernização da agricultura, sofrendo com elevadas transferências de renda para fora do setor. Uma forma de ressarci-los seria implementando uma política de estabilização de renda que asseguraria rentabilidade estável aos produtores. O objetivo deste artigo é determinar os benefícios de uma política de estabilização de renda implementada na agricultura familiar para agricultores e consumidores de arroz, feijão, milho e mandioca, e os custos para agricultores comerciais nesses mercados. Utilizou-se o modelo de Newbery e Stiglitz, que considera a redução do risco com a política de estabilização de renda. A política implicaria aumento de receita para produtores familiares. Os benefícios de transferência superariam os de eficiência para produtores familiares e consumidores. Os benefícios para a agricultura familiar superariam os custos da agricultura comercial com a política nos mercados de feijão, mandioca e milho, e os benefícios totais superariam os custos totais nos mercados de feijão e milho, ao contrário ocorreria nos mercados de arroz e mandioca, embora neste fosse pequena a diferença. Conclui-se que a implementação da política seria viável nos mercados onde a participação da agricultura familiar fosse maior que a da comercial e naqueles importadores

Analysis of Chiral and Achiral Medium Based Coplanar Waveguide Using Improved Full Generalized Exponential Matrix Technique

YesIn this work, an analytical study of the electromagnetic propagation in a complex medium-based suspended three-layer coplanar waveguide (CPW) is carried out. The study aims at a numerical calculation of the dominant hybrid mode complex propagation constant in the CPW printed on a bianisotropic substrate. The herein considered bianisotropy is characterized by full 3×3 tensors of permittivity, permeability and magnetoelectric parameters. The study is based on the numerical derivation of the Green's functions of such a complex medium in the spectral domain. The study is carried out using the Full Generalized Exponential Matrix Technique based on matrix- shaped compact mathematical formulations. The Spectral Method of Moments (SMoM) and the Galerkin's procedure are used to solve the resulting homogeneous system of equations. The effect of the chiral and achiral bianisotropy on the complex propagation constant is particularly investigated. Goo d agreements with available data for an anisotropic-medium-based suspended CPW structure are achieved. Various cases of chiral and achiral bianisotropy have been investigated, and particularly, the effect on the dispersion characteristics is presented and compared with cases of isotropic and bianisotropic Tellegen media.FCT/MEC through national funds and when applicable co-financed by the ERDF, under the PT2020 Partnership Agreement under the UID/EEA/50008/2019 project

The Specificity of Peptides Bound to Human Histocompatibility Leukocyte Antigen (HLA)-B27 Influences the Prevalence of Arthritis in HLA-B27 Transgenic Rats

Human histocompatibility leukocyte antigen B27 is highly associated with the rheumatic diseases termed spondyloarthropathies, but the mechanism is not known. B27 transgenic rats develop a spontaneous disease resembling the human spondyloarthropathies that includes arthritis and colitis. To investigate whether this disease requires the binding of specific peptides to B27, we made a minigene construct in which a peptide from influenza nucleoprotein, NP383-391 (SRYWAIRTR), which binds B27 with high affinity, is targeted directly to the ER by the signal peptide of the adenovirus E3/gp19 protein. Rats transgenic for this minigene, NP1, were made and bred with B27 rats. The production of the NP383-391 peptide in B27+NP1+ rats was confirmed immunologically and by mass spectrometry. The NP1 product displaced ∼90% of the 3H-Arg-labeled endogenous peptide fraction in B27+NP1+ spleen cells. Male B27+NP1+ rats had a significantly reduced prevalence of arthritis, compared with B27+NP− males or B27+ males with a control construct, NP2, whereas colitis was not significantly affected by the NP1 transgene. These findings support the hypothesis that B27-related arthritis requires binding of a specific peptide or set of peptides to B27, and they demonstrate a method for efficient transgenic targeting of peptides to the ER

Analysis of the combinatory effect of uniaxial electrical and magnetic anisotropy on the input impedance and mutual coupling of a printed dipole antenna

YesThe main objective of this work is to investigate the combinatory effects of both uniaxial magnetic and electrical anisotropies on the input impedance, resonant length and the mutual coupling between two dipoles printed on an anisotropic grounded substrate. Three different configurations: broadside, collinear and echelon are considered for the coupling investigation. The study is based on the numerical solution of the integral equation using the method of moments through the mathematical derivation of the appropriate Green’s functions in the spectral domain. In order to validate the computing method and evaluated Matlab® calculation code, numerical results are compared with available literature treating particular cases of uniaxial electrical anisotropy; good agreements are observed. New results of dipole structures printed on uniaxial magnetic anisotropic substrates are presented and discussed, with the investigation of the combined electrical and magnetic anisotropies effect on the input impedance and mutual coupling for different geometrical configurations. The combined uniaxial (electric and magnetic) anisotropies provide additional degrees of freedom for the input impedance control and coupling reduction.This work is part of the POSITION-II project funded by the ECSEL joint Undertaking under grant number Ecsel-7831132-Postitio-II-2017-IA,www. position-2.eu and partly funded by FCT/MCTES through national funds and when applicable co-funded EU funds under the project UIDB/50008/2020- UIDP/50008/2020. This work was also supported in part by the DGRSDT (General Directorate of Scientific Research and Technological Development) - MESRS (Ministry of Higher Education and Scientific Research), Algeria, and RTI2018-095499-B-C31, Funded by Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER,UE)