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A theoretical model to study the localized surface spin states, along two different directions [001] and [011] is presented. The model is mainly used to analyze the antiferromagnetic monoxide network of spins, using the matching method theory. The magnon spectrum is determined by numerical calculations based on the Landauer-Büttiker formalism of the scattering matrix. Our simulation results show the interference effects between magnon states of the monoxide continuum and the localized magnon modes created by the surface region with Fano resonance characteristics. Additionally, the results are obtained by computing different possibilities of the magnetic parameters, characterizing the antiferromagnetic and the ferromagnetic couplings between spin sites on the monoxide structures. The interactions between the refection and the propagating spin modes describe several types of oscillations. We notice that the magnetic spectra at the surface of monoxide lattices are proportional to the magnetic coupling and the spin intensity of the antiferromagnetic lattices. Simulations and numerical calculations relating to spin excitations in monoxide lattices make it possible to extract useful information for the elaboration of sensors for specific applications. [ABSTRACT FROM AUTHOR]

Metal particles, difficult to be eliminated in gas-insulated metal-enclosed switchgear (GIS), can cause GIS discharge and breakdown between electrodes, or flashover on the insulator surface. It influences the development of ultra-high voltage (UHV) projects. Therefore, the work optimised the model of metal particle movement under AC voltage, studying the metal particle movement and distribution characteristics between ball-plane electrodes through experiment and simulation. Under AC voltage, the particle jumps on a small scale on the plane surface. With the increase of voltage, the jump amplitude increases. However, the collision frequency decreases until the particle collides with the ball electrode. When the initial phase angle of power changes, the particle-moving pattern is symmetrical in the angle ranging from 0 to 180°, and from 180 to 360°. The collision frequency changes slightly with the increase of jump amplitude when the angel ranges from 0 to 120°.

• We present a rigorous method to evaluate the scattering of a plane electromagnetic wave by a perfectly conducting elliptic cylinder parallel to a generally reflecting plane surface. • The solution is based on the Spectral Domain method and the plane-wave expansion of the elliptical cylindrical waves. • The surface is characterized by means of a reflection coefficient. • The analytical method is implemented in specific computational code to achieve a numerical solution. • Results are validated by means of a finite element method commercial software. Validation trials, show good agreement between the two independent computational methodologies. In this paper, we present a rigorous analytical and numerical method to evaluate the scattering of a plane electromagnetic wave by an infinite, perfectly conducting elliptic cylinder parallel to a non-perfectly reflecting plane surface. The analytical solution is based on the spectral domain method and the plane-wave expansion of the elliptic cylindrical waves and is applicable in a broad variety of cases in which the properties of the plane surface may be expressed by means of a reflection coefficient. The proposed approach is suitably implemented in a specific computational code to achieve a numerical solution. Results of validation trials, performed by using finite element method commercial software, are provided. [ABSTRACT FROM AUTHOR]

Elliptic Cylindrical Waves (ECW), defined as the product of an angular Mathieu function by its corresponding radial Mathieu function, occur in the solution of scattering problems involving two-dimensional structures with elliptic cross sections. In this paper, we explicitly derive the expansion of ECW, along a plane surface, in terms of homogeneous and evanescent plane waves, showing the accuracy of the numerical implementation of the formulas and discussing possible applications of the result. [ABSTRACT FROM AUTHOR]

On the basis of analytical solutions of classical tasks, by analogy with the latter but using qualitative methods, the criteria of realization of the instability of a free surface of conductive liquid for its different geometry are derived for uniform and nonuniform distribution of surface density induced by an external electrostatic field or its own charge. The criteria of instability of a charged jet, a charged spheroidal drop, and a plane surface of the conductive liquid are found in a nonuniform electrostatic field of a point charge, thin loaded rod, and dipole. [ABSTRACT FROM AUTHOR]

Heat transfer between the vertical and inclined (45°) plane surface, and the longitudinally upward flow of statically stable foam was investigated experimentally. The value variation regularities of the heat transfer coefficient along and across the plane surface were determined. The dependence of the mean intensity of the plane surface heat transfer to the foam flow on the foam volumetric void fraction and flow velocity was determined, and the criterion equation was obtained. It was noticed that the intensity of the inclined (45°) plane surface cooling by the foam flow was more than that of the vertical surface. The comparison of the mean intensity of the vertical plane surface cooling with that of the in-line 1.5x 1.5 tube bundle showed that the cooling of the tube bundle was more intensive. [ABSTRACT FROM AUTHOR]

Abstract: Design and operation of a double-fiber sensor for displacement measurements are reported in this study. In this arrangement, one fiber transmits the laser light to the target and the second one receives the light reflected off the target and transmits to a photodetector. Utilizing inexpensive plastic optical fibers offers advantages such as higher reflexability and more robustness at a reasonable cost, which are required for some applications. The novelties of the reported design are compactness of the fiber probe, flexibility, long dynamic range (22mm), and it is possible to use the source and the detector at the same side. The displacement of the target causes the intensity modulation and such a power variation is the base of sensor operation. Measurements for the metallic and non-metallic surfaces are performed and the results for aluminum, copper, and bronze sheets are presented here. Our results indicate that the sensitivity is highest for the plane mirror (288.8mV/mm), high for the shiny metallic surfaces (230.6mV/mm), but it can be used for other surfaces with a reasonable sensitivity. Important parameters of the sensor such as reproducibility (1.0%) and hysteresis effect (1.8%) are also investigated for this device. The theoretical formulation of the sensor operation is also developed and the computed results are compared with the experimental ones. The obtained experimental respond curve agrees well with the theoretical one, which verifies the successful operation of the proposed sensor system for precise displacement measurements. [Copyright &y& Elsevier]

The present work describes the mass transfer process between a moving fluid and a slightly soluble solid mass buried in a packed bed of small inert particles with uniform voidage, by both advection and diffusion/dispersion. Numerical solutions of the differential equations describing solute mass conservation were undertaken to obtain the concentration profiles, for each concentration level, the width and downstream length of the corresponding contour surface and the mass transfer flux was integrated to give the Sherwood number as a function of the relevant parameters. Mathematical expressions that relate the dependence with the Peclet number and aspect ratio are proposed to describe the approximate size of the diffusion wake downstream of the reactive solid mass. [ABSTRACT FROM AUTHOR]

The contact interaction of a pneumatic tire with a roadbed is studied. The discrepancy between the Gim-Nikravesh analytic model and experimental data is established to be due to the one-dimensionality of the model and the assumption that the pressure of the wheel on the roadbed is symmetric [ABSTRACT FROM AUTHOR]

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Discrete track media were successfully fabricated by Cr ion implantation. The saturation magnetization of the CoCrPt-SiO2 perpendicular recording layer was decreased down to 6% by implanting Cr ions with a dosage of 1 x 1017 ions/cm² and an ion energy of 20 keV. A resist mask with a discrete track pattern was prepared by e-beam lithography and the pattern was transferred to the recording layer by Cr ion implantation. A clear magnetic contrast of the tracks was observed and the average surface roughness was maintained less than 1 nm. A clear servo signal was obtained by spin-stand measurement using a flying head. Feasibility of discrete track media fabrication by Cr ion implantation was confirmed. [ABSTRACT FROM AUTHOR]