Screw dislocation in functionally graded magnetoelectroelastic solids

A screw dislocation in a functionally graded magnetoelectroelastic material is investigated. The material properties exponentially changing along both x and y directions are considered and the mechanical–electric–magnetic coupling is discussed. Closed-form expressions for the mechanical, electric and magnetic components are derived using the general stress function method. The solutions can be applied as a fundamental result and reduced into the classic and piezoelectric cases. The study puts forth a direct way for screw dislocation analysis in inhomogeneous structures with multifield coupling.     

Simultaneous determination of thin-film inertia and shear stiffness using thickness-twist and face-shear modes of an AT-cut quartz resonator

We propose the use of thickness-twist (TT) and face-shear (FS) vibration modes of an AT-cut quartz crystal plate resonator for simultaneous determination of the inertia and stiffness of a thin film deposited on a crystal surface. A theoretical analysis using Mindlin's first-order theory for crystal plates is performed to demonstrate the idea. Expressions for the stiffness ratio and mass ratio between the thin film and the resonator are presented in terms of frequency shifts of FS and TT modes, which are experimentally measurable. A numerical example is given.     

A piezoelectric gyroscope based on thickness-shear modes of an AlN bimorph with inclined c-axes

We propose a new structure for piezoelectric gyroscope application. It consists of a two-layered plate of AlN with inclined c-axes. Through a theoretical analysis, it is shown that when the plate is electrically driven into thickness-shear (TSh) vibration in one direction and is rotating about the plate normal, the rotation causes a TSh vibration in a perpendicular direction with an electrical output which can be used to measure the angular rate of the rotation. Since AlN can be made into thin film devices much smaller than conventional crystal acoustic wave devices, the proposed gyroscope can be made much smaller than existing piezoelectric gyroscopes. The structure can also work with other crystals of class 6mm such as ZnO and polarized ceramics.     

Grain boundary phase observed in Al–5 at.% Zn alloy by using HREM

The nature and behaviour of grain boundary (GB) phases is very important since they can control strength, plasticity, resistivity, grain growth, corrosion resistance, etc, especially in nanocrystalline materials. For nanocrystalline Al-based light alloys, extremely high plasticity has been observed in restricted temperature and concentration intervals close to the solidus line. This phenomenon is not fully understood. It can be explained by formation of GB phases not included in the bulk phase diagram. Therefore, the structure of GB phases, as well as thermodynamic conditions for their existence, has to be carefully studied. In this work the structure and composition of GBs and GB triple junctions in Al–5 at.% Zn polycrystals annealed in the temperature region above and below the bulk solidus line were studied by high-resolution electron microscopy and analytical transmission electron microscopy. Evidence has been obtained that a thin layer of a liquid-like phase exists in GBs and GB triple junctions slightly below the bulk solidus line.     

A general solution of elasto-hydrodynamics of two-dimensional quasicrystals

Dynamic problems of quasicrystals are analysed within the framework of continuum mechanics. Phonon excitations yield wave propagation while phason excitations yield atomic diffusion. Phonon fields obey the equations of motion and phason fields obey the diffusion equations. Governing equations of elasto-hydrodynamics of decagonal quasicrystals combine characteristics of the equations of motion and diffusion. A general solution is derived in terms of two introduced auxiliary functions. It provides an easy-to-use approach to solve initial-boundary value problems encountered in elasticity problems for quasicrystals. Explicit expressions for displacements and stresses in the phonon and phason fields can be directly obtained. A derived general solution is also applicable to some planar quasicrystals such as pentagonal quasicrystals with fivefold symmetry.     

Quantum information in an evolutionary perspective

An approach to quantum phenomena is reviewed that deals with the possibility of their realistic interpretation in the sense that they represent manifestations of hermeneutic circles between quantum “objects” and their experimental boundary conditions. Quantum cybernetics provides an evolutionary perspective in that all higher‐level organizations like molecules, cells, living systems, etc., can be discussed under one and the same systemic viewpoint: a hermeneutic circularity between a “core” (or “nucleus") and a relevant “periphery” (or “environment") which constitutes the systems’ organization and information potential.

Generally, in realistic theories, an individual quantum system is analyzable into a local “particle‐like” nonlinearity of a generally nonlocal “wave‐like” mode of some sub‐quantum structure of the vacuum ("Dirac ether"). In this view, a “particle” can be considered as being “guided” along one specific route by the (generally nonlocal) configurations of superimposed waves, which spread along all possible paths of an experimental setup. Moreover, in the approach of Quantum Cybernetics, an additional focus is given on the fact that the energy and momentum of a particle also determine the wave behavior. Thus, “waves” and “particles” are mutually and self‐consistently defined, and Quantum Cybernetics puts particular emphasis on the circular relationship—mediated by plane waves—between a quantum system and its macroscopically defined boundary conditions.     

认知决策中锚定效应的量子模型研究

文章回顾了锚定效应研究中个体层面和群体层面的相关文献,认为选择易得性模型理论能够很好地解释锚定效应的发生机制。同时,通过回顾决策认知领域的最新研究观点——量子模型,包括从只利用量子论空间性质到使用薛定谔方程的两种表述,阐述了这一领域的研究趋势。并通过为锚定效应建立量子模型(个体层面和两人层面),拓展了锚定效应的研究。     

COSMOLOGY FROM ALPHA TO OMEGA: RESPONSE TO REVIEWS

I gratefully acknowledge and respond here to four reviews of my recent book, Cosmology from Alpha to Omega. Nancey Murphy stresses the importance of showing consistency between Christian theology and natural science through a detailed examination of my recent model of their creative interaction. She suggests how this model can be enhanced by adopting Alasdair MacIntyre's understanding of tradition in order to adjudicate between competing ways of incorporating science into a wider worldview. She urges the inclusion of ethics in my model and predicts that this would successfully challenge the competing naturalist tradition in contemporary society. John F. Haught weighs the alternatives of viewing divine action as objective versus subjective and of divine action at one level in nature or at all levels. He asks whether physics is fundamental to nature, arguing instead that metaphysics should be considered as fundamental. Michael Ruse assesses occasional versus universal divine action, the problems raised to divine action when it is related to quantum mechanics, and the way these relations exacerbate the challenge of natural theodicy. As an alternative he suggests viewing God as outside time and acting through unbroken natural law. Willem B. Drees discusses my use of the bridge metaphor for the relation between theology and science, the implications when science is inspired by theology, the role of contingency and necessity in the anthropic principle/many-worlds debate, and the challenge of cosmology to eschatology with the ensuing problem of theodicy.     

On Different Proof-Search Strategies for Orthologic

In this paper, we consider three different search strategies for a cut-free sequent system formalizing orthologic, and estimate the respective search spaces. Applying backward search, there are classes of formulae for which both the minimal proof length and the search space are exponential. In a combined forward and backward approach, all proofs are polynomial, but the potential search space remains exponential. Using a forward strategy, the potential search space becomes polynomial yielding a polynomial decision procedure for orthologic and the word problem for free ortholattices.