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Local Properties (local + property)
Selected AbstractsForce Spectroscopic Investigations During the Local Oxidation of n -Octadecyltrichlorosilane Monolayers,ADVANCED FUNCTIONAL MATERIALS, Issue 1 2006S. Hoeppener Abstract Scanning force spectroscopy (SFS) is a powerful tool for investigating surface properties with high precision. Unlike most common spectroscopic techniques, information about local properties can also be obtained from surface areas with nanometer dimensions. This makes SFS a useful investigative tool for small lithographic structures. We apply the continuous recording of force curves to extract valuable information about the local oxidation of a monolayer of n -octadecyltrichlorosilane molecules self-assembled on silicon. The oxidation is carried out while simultaneously recording the force curves during the application of a bias voltage to the tip. The dynamics of the induced surface modifications and changes in the surface properties are followed by analyzing specific spots in the force curves. [source] A comprehensive catastrophe theory for non-linear buckling of simple systems exhibiting fold and cusp catastrophesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 2 2002X. A. Lignos Abstract Non-linear static buckling of simple systems associated with typical discrete critical points is comprehensively presented using elementary Catastrophe Theory. Attention is focused on the Fold and Cusp Catastrophe, all local properties of which are assessed in detail. Hence, in dealing with stability problems of potential systems there is no need to seek any of these properties since all of these are known a priori. Then, one has only to classify, after reduction, the total potential energy of a system into one of the universal unfoldings of the above types of catastrophe. Two illustrative numerical examples show the methodology of the proposed technique. Copyright © 2002 John Wiley & Sons, Ltd. [source] Do local properties function as cues for musical key perception?,JAPANESE PSYCHOLOGICAL RESEARCH, Issue 2 2009RIE MATSUNAGA Abstract:, A global property (i.e., pitch set) of a melody appears to serve as a primary cue for key identification. Previous studies have proposed specific local properties in a melody (e.g., the augmented fourth, the perfect fifth, etc.) that may function as further cues. However, the role of the latter in key identification is controversial. The present study was designed to investigate what kinds of local properties, if any, function as reliable cues for key identification. Listeners were asked to identify keys for 450 melodies that consisted of the same pitch set, but which differed in sequential constraints. Using multiple discriminant analyses, we evaluated relative contributions of as many kinds of local properties as possible (e.g., single intervals, single pitch classes in each sequential position, etc.). The results showed that, except for the pitch class of the final tone, for which interpretation should be taken cautiously, none of the specific local properties examined contributed significantly to key identification. This finding suggests that, contrary to prior findings, key identification is derived from unidentified properties other than the specific local properties. [source] Granular mixing and segregation in a horizontal rotating drum: A simulation study on the impact of rotational speed and fill levelAICHE JOURNAL, Issue 12 2008M. M. H. D. Arntz Abstract The rich phase behavior of granular beds of bidisperse hard spherical particles in a rotating horizontal drum is studied by Discrete Element Method (DEM) simulations. Several flow regimes and various forms of radial segregation, as well as mixing, are observed by systematically varying the operational parameters of the drum, i.e. fill level and angular velocity, over a wide range. Steady states after several dozen revolutions are summarized in two bed behavior diagrams, showing strong correlations between flow regime and segregation pattern. An entropy method quantifies the overall degree of mixing, while density and velocity plots are used to analyze the local properties of the granular bed. The percolation mechanism may provide a qualitative explanation for the distinct segregation processes, and for the transient mixing in nonradially segregated beds. Initially blockwise segregated beds are found to mix before radial segregation sets in. High fill fractions (>65%) show the most intense segregation. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] Local Viscosity of Si-O-C-N Nanoscale Amorphous Phases at Ceramic Grain BoundariesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2001Giuseppe Pezzotti Internal friction characterization has been used to quantitatively assess the viscosity characteristics of Si-O-C-N glasses segregated to nanometer-sized grain boundaries of polycrystalline Si3N4 and SiC ceramics. A relaxation peak of internal friction, which arises with rising temperature from the viscous sliding of glassy grain boundaries, was systematically collected and analyzed with respect to its shift upon changing the oscillation frequency. As a result of such an analysis, both activation energy for viscous grain-boundary flow and inherent viscosity of the intergranular glass film could be quantitatively evaluated. Two main features are shown: (i) the presence of N and/or C greatly affects the viscosity characteristics of SiO2 phases at Si3N4 and SiC grain boundaries; and (ii) the internal friction method has potential as a unique experimental tool for understanding the local properties of nanoscale amorphous phases in new ceramic materials. [source] Search for solar cycle changes in the signature of rapid variation in BiSON dataMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2004G. A. Verner ABSTRACT The second helium ionization zone and the base of the convective envelope are regions of rapid variation of solar structure which introduce characteristic signatures into the frequencies of p-mode oscillations. These signals provide a direct seismological method to probe the acoustic properties of these regions. In this work we isolate these signatures in over 9 yr of low-degree BiSON data and extract information on the acoustic depth and local properties from each signal. Any temporal variations are investigated by fitting the signals extracted from 432, 864 and 1728-d spectra. The extracted parameters are found to be in agreement over the different length spectra and within one formal standard deviation of the values obtained for model ,S'. There is no evidence found for any systematic variation in the acoustic depth, width or magnitude of the second helium ionization zone, which suggests any activity-dependent disturbance to the near surface layers does not propagate down to this layer. The convection zone signal does show some temporal variation that may be correlated with solar activity, although further analysis with current data is required. The isolation of these signatures in low-degree data confirms that this method can be used to provide structural information on Sun-like stars once similar asteroseismic data become available. [source] The Noise Prediction Model SATINPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2003J. Ostertag Dipl.-Ing. This paper presents the noise prediction model SATIN (Statistical Approach to Turbulence Induced Noise) which is based on Lighthill's acoustic analogy. It allows to predict both, the far-field noise radiation as well as near-field wall-pressure fluctuations. Far-field noise radiation may result from the scattering of wall-pressure fluctuations at geometrical discontinuities and is therefore important for many practical problems. Within this paper, we focus on the calculation of far-field noise radiation. The required input values of SATIN are local properties of turbulence, namely the turbulent kinetic energy and the integral length scale which can be obtained by steady solutions of the Reynolds-averaged Navier-Stokes equations with a two equation turbulence model. It is assumed that the turbulence is axisymmetric and homogenous, which is taken into account by introducing two anisotropy parameters. The validation of SATIN is done for trailing-edge noise originating from a thin flat plate using measurements of a phased array. As expected, the anisotropic formulation of SATIN improves the prediction quality considerably compared to isotropic turbulence. [source] | |||||||||||||