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The present study investigates the traversal of torsional wave at a corrugated interface between viscoelastic sandy medium and inhomogeneous half-space. In the lower half-space, the inhomogeneity has been assumed as an exponential variation in density and rigidity with respect to depth. We have taken the method of variable separation to obtain analytical solution of displacement components for layer and half-space. Consequently, we have obtained the wave velocity equation of torsional wave using sufficient boundary conditions. Moreover, the wave velocity equation has been reduced to the pre-established classical relationship of Love wave, when both the media are isotropic and homogeneous, as shown in special case. The comparative study of the influence of various parametric traits viz. sandiness, viscoelasticity, corrugated and inhomogeneity associated with the studied model on the traversal characteristics of torsional wave is one of the salient feature of the current investigation. The study may find its possible applications in various seismic prospecting techniques to analyse the nature of torsional wave propagation in the considered layered media. [ABSTRACT FROM AUTHOR]

It is a certainty that a rock massif is a very complex environment, known only partially; in the laboratory we cannot produce all the details encountered in situ; therefore, most of the properties determined experimentally not fully express their real value that they have in rock massif. As theoretical basis we might consider theory of similitude initiated by Newton, in the sense of similarity that we can establish to the boundary between theory and experiment. Based on this and considering the applicable theorems that define main properties and recognition criteria of phenomena to different scales to which material systems are analyzed and implicitly rocks, we have studied the variation manner of rock characteristics established on specimens of different shapes and sizes. This paper presents the influence of scale effect under mechanical characteristics of rocks, as result of studies realized on both cubical and cylindrical specimens. Increasing of geometric dimensions of the specimen involves a higher degree of inhomogeneity of rocks as regards the presence of discontinuities in specimens mass. An own calculation relationship of compressive breakage strength when the specimens cannot be performed to the diameter of 50 mm and for a slenderness ratio equal to 2, it is also proposed. [ABSTRACT FROM AUTHOR]

The present paper is concerned with the propagation of shear waves in an anisotropic inhomogeneous layer whose elastic constants are functions of temperature. The dependence of material properties on temperature gives rise to inhomogeneity of the layer which is one of the trivial characteristics of the constituent layers of earth which may cause due to the presence of various types of elements and compounds beneath the earth. The layer is lying over a rigid foundation and there is no loading on the upper boundary. The dispersion equation of shear waves has been obtained in closed form. Numerical computations are performed and graphs are plotted to show the effect of inhomogeneity and anisotropy factors on the dimensionless phase velocity. It is found that the phase velocity is considerably influenced by the inhomogeneity and anisotropy of the layer. [ABSTRACT FROM AUTHOR]

The sensitivity of magnetic Barkhausen noise (MBN) profile to changes in the excitation field strength has been investigated in case carburized EN36 steel. In general, the 0.5 mm case depth EN 36 steel specimen induces a double peak profile indicative of inhomogeneity through the detected depth in the magnetized landscape. Various excitation field amplitudes have been applied to the electromagnet to generate various excitation fields on the specimen surface. Excitation field at the lowest level induced an MBN emission of two peaks of equivalent heights at low current value. The first peak occurs at lower field than the second peak in each half magnetization cycle. As the excitation field increases, the height of both peaks increased but the second peak, at higher field, increases in a higher rate than that of the first peak at lower field. Beyond certain magnetizing voltage, both peaks heights began to saturate and no further increase in the MBN intensity has been noticed. The results are discussed on the basis of the available theories on MBN. [ABSTRACT FROM AUTHOR]

This work consists of a review and a systematical study of the process followed in thermal poling of polymeric thin films. Starting from the preparation of samples, the characterization of the materials used, up to the determination of their linear, nonlinear optical and electrical properties, a series of steps are presented, based on recent literature in this field. Using the available means within the optimum conditions emphasized in the literature, poling experiments on four different guest-host systems were carried out and compared. The results obtained show a significant increase in the degree of alignment of guest molecules in the host polymers with high Tg. Inhomogeneity on the surface of poled films was proven by SEM images and UV-visible absorption spectrum of the poled samples. [ABSTRACT FROM AUTHOR]

In this study, a mesoscopical inhomogeneous finite element method (MIFEM) of metal forming process is performed to predict surface roughening behavior. The mesoscopical inhomogeneous material parameter and its determination method obtained from microstructure observation and uni-axial tensile test are suggested. The validity of the MIFEM taking into consideration the mesoscopic material inhomogeneity determined by the above-mentioned method is verified by comparison with experimental results of free surface roughening and necking behavior under uniaxial tensile states. In addition, the validity of proposed MIFEM can be verified for the micro deep drawing process with contact situation between material and dies. From these results, the validity of proposed MIFEM for prediction of inhomogeneous deformation behavior of metal foil can be verified. [ABSTRACT FROM AUTHOR]

Bounded plasma exhibit many interesting behavior that are not found in plasmas of "infinite" extent such as space and astrophysical plasmas. Our studies have revealed that the dispersion properties of waves in a bounded magnetoplasma deviates considerably from the predictions of the Clemmow-Mullaly-Allis (CMA) model, giving rise to new regimes of wave propagation and absorption. The anisotropy of the medium dictated by the length scales of plasma nonuniformity and magnetostatic field inhomogeneity lead to rotation of the polarization axis an effect similar to the Cotton-Mouton effect in a magneto-optic medium but with distinct differences due to wave induced resonances. This article highlights some of these interesting effects observed experimentally and corroborated with Monte Carlo simulations. One of the principal outcomes of this research is the genesis of a novel multielement focused ion beam (MEFIB) system that utilizes compact bounded plasmas in a minimum - B field to provide intense focused ion beams of a variety of elements for new research in nanoscience and technology. [ABSTRACT FROM AUTHOR]

Hydrological parameters have major impact to water, energy, civil engineering, industry and other commercial and non-economic branches. For the determination of the hydrological processes are: observed, measured and recorded data on hydrological phenomena. Our knowledge of these phenomena modes is the basis for good planning and management of water resources. As a source of information for defining the characteristics we used measured data. The effectiveness of water systems depends on the measurement and hydrological phenomena, depends of the impact of inaccurate data. Scientific's paper refers to the collection of hydrological data, determining the properties, checking their accuracy, testing consistency and homogeneity caused by natural or artificial means. For this purpose will we used, ANOVA model for analysis of variance and software for computer modeling, which this paper presents good technique for determining the variables of hydrological processes. [ABSTRACT FROM AUTHOR]

Studies were conducted on inhomogeneous distribution of acoustic field in shallow water target radiated noise measurement. Acoustic vector processing theoretical model for this scenario was derived, and detailed examples showed that the inhomogeneous distribution of acoustic fields in testing sea is related to many factors, such as target sound source structure, radiation directivity, the bandwidth and frequency of the signals, boundary constraint, seabed acoustic properties, the spatial location of sound sources, navigation condition of target acoustic sources and so on. The simulation and field test results show that considering the inhomogeneous distribution of acoustic field can improve the accuracy of radiated noise measurement. [ABSTRACT FROM PUBLISHER]

We analyze the plane-parallel bias of the shortwave cloud radiative forcing (SWCRF) of liquid and ice clouds at 1 degree scales using global MODIS (Terra and Aqua) cloud optical property retrievals for four months of 2005 representative of the meteorological seasons. The (negative) bias is estimated as the difference of the SWCRF calculated using the Plane-Parallel Homogeneous (PPH) method and the Independent Column Approximation (ICA). These calculations require MODIS-derived means (for PPH calculations) and distributions (for ICA calculations) of cloud optical thickness and effective radius as well as ancillary surface albedo and atmospheric information, that are inserted into a broadband solar radiative transfer code. The absolute value of global SWCRF bias of liquid clouds at the top of the atmosphere is ∼6 Wm-2 for MODIS overpass times while the SWCRF bias for ice clouds is smaller in absolute terms by ∼0.7 Wm-2, but with stronger spatial variability. Marine clouds of both phases are characterized by larger (more negative) SWCRF biases than continental clouds. For clouds of both phases the SWCRF bias is collectively about 4 Wm-2 for diurnal averages. [ABSTRACT FROM AUTHOR]

The local electronic properties of Bi2Sr1.6Ln0.4CuO6+y, (Ln = La, Gd) is investigated by scanning tunneling microscopy/spectroscopy (STM/STS). As increasing the magnitude of out-of-plane disorder by increasing the mismatch of Ln-ion doping, enlargement of deviation of Δ (σΔ) is detected. The value of σΔ is linearly enhanced as decreasing Tc including the results of optimum Bi2Sr2CaCu2O8+y. These results suggest the out-of-plane disorder suppresses the superconductivity and enhances pseudogap regions in superconducting state efficiently. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this work, I-V characteristics of Al/p-Si Schottky (SD) diode were measured in the temperature range of 178–440 K. Obtained data were analyzed a Gaussian distribution of the barrier height (BH). It has been concluded that the temperature dependence of the forward I-V characteristics of the Schottky barrier diodes can be explained on the basis of thermionic emission (TE) mechanism with a Gaussian distribution of the barrier heights. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]