Authors:E. Firatligil-Durmuş, A. Sýkorová, E. Šárka, Z. Bubník, M. Schejbal, and J. Příhoda
Digital image analysis was used to test the quality parameters of six varieties of
L. and one variety of
L. — projected area, equivalent diameter, MaxFeret and MinFeret (minimum or maximum perpendicular distance between parallel tangents touching opposite sides of the profile of the chosen object), perimeter, thickness and crease depth (both measured using a digital calliper) of a kernel ranging from 16.52–20.22 mm
, 4.58–5.07 mm, 16.70–20.82 mm, 6.21–7.29 mm, 3.32–3.78 mm, 2.69–3.12 mm, 0.23–0.42 mm. The size data were used for calculation of volumes and surface areas of wheat kernels modelled as a general ellipsoid. The calculation of surface area using finite element method (FEM) was based on computer software MAPLE 9.0 and the results were compared with a simplified method. The volumes of kernels from the ellipsoid model were corrected with consideration of measured average crease depth; the difference was then max. 3.6%.We tested the correlation of volume and surface areas obtained from the ellipsoidal model with the measured projected areas; the resulting high correlation coefficient for the varieties of
enables the use of only 2D image analysis measurement, for quick estimation of surface and volume parameters, without time consuming thickness measuring. However, the shape of
kernels was a little different and the designed geometrical model was thus not suitable.We recommend image analysis as a simple and rapid method for obtaining the parameters of wheat grain for engineering purposes.
analytic solutions derived for simple geometricmodels. It is clear that the actual burn off behaviour of both graphite samples differed greatly from the predictions. The analytic solutions feature burn off functions that either increase or decrease with
Authors:Radu Sestraş, Lorentz Jäntschi, and Sorana Bolboacă
A small series of steroid hormones and synthetic steroid anabolics, eluted from a sample by using classical methanol-water mobile phase, was designed at molecular level with in vitro geometrical modeling. Structure-based properties of the compounds were extracted for different strategies of geometry optimization and were related with the percent retardation factors observed in the experiment by using classical linear regression approach. The obtained models were assessed and the most accurate model was selected. The obtained relationship between the structure and retardation factor was interpreted in order to express the main factors driving liquid phase mobility of compounds as a function of their structure. The analysis allowed a series of general conclusions regarding the modeled property (percent of retardation factor), modeling strategy (with help of a family of molecular descriptors) as well as about the level of theory in geometrical modeling (Ab-initio 6-31G*, CLHF, core Hamiltonian guess, symmetric orthogonalization).
The paper stresses the need to distinguish between two subtypes of binary laryngeal systems, viz. [voice] languages versus [spread glottis] languages (“laryngeal realism”—Honeybone 2005). It criticizes the use of the primes H and L for this distinction in Government Phonology, and proposes an alternative representation, based on Backley-Takahashi (1998) and Nasukawa-Backley (2005). This feature geometric model assumes the same set of melodic components for obstruents and sonorants within a system but with a difference in the status of source elements across the language types. Therefore, accompanied by the mechanism of element activation, it is claimed to capture the cross-linguistic observations more adequately.
Authors:Nan Qian, Thomas Krings, Eric Mauerhofer, Dezhong Wang, and Yunfei Bai
Improved methods for the reconstruction of the isotope specific activity content in nuclear waste drums with data obtained
by a gamma scanning system developed at Shanghai Jiao Tong University require an analytical function of the detector response.
In this work we derive an analytical detector response function for a collimated HPGe detector with a square collimation window.
The model is based on a purely geometric model respecting the configuration of the collimated detector system, the positions
of radioactive point sources and the absorption of γ-rays in the matrix as well as in the HPGe crystal. We show that the derived
analytical detector response function is in good agreement with data simulated by MCNP5.
In this paper the following themes ate discussed: the original meaning of two words: the Greek ballein (βάλλω) and the Latin aleatory (aleatorius). The signs of subtraction (−), division (\), and absolute value (|a|). The meanings of the words hyperbola (ύπɛρβάλλω) and symbol (σύμβgoλgoν). The sign of the Greek and Saint Andrew’s Cross (Crux decussata), addition (+) and multiplication (X).Origin in the Eucledian geometry and in the hyperbolic space. The center point of the ball and the Cartesian coordinate system on the sphere.The crucifix: its horizontal direction is a stretching line, reciprocal vector (←→, ↔), its vertical direction (on the cross) gravitates (↓), and rises at the time of the church building (↕). Corpuscular matrix, the mosaic and the experience of color in divisionism (the centre point of the quadruple division, grid and pixel). The modern gnostic idea of the geometrical model, the logic of “there is only one whole” and a defense of the immortality of the soul (Bernard Bolzano).
The reactions between silicon nitride and carbon take place in two stages, the surface silica of silicon nitride powders reacts
with carbon first followed by the decomposition of silicon nitride and the residual silicon reacting with carbon. The kinetics
of the two stage reactions has been studied by isothermal thermogravimetric analysis. Physico-geometric models for both of
the reaction stages have been proposed, and the kinetic parameters have been calculated. The implications of the kinetic models
and parameters are discussed.
Authors:József Prokisch, Levente Czeglédi, Béla Kovács, Lajos Daróczi, Éva Széles, János Tamás, Frédéric Mabille, and Zoltán Győri
Marshall, D.R. Ellison, F.W. and Mares, D.J. (1984) Effects of grain shape and size on milling yields in wheat. I. Theoretical analysis based on simple geometricmodels. Australian Journal of Agricultural Research. 35.(5) 619
Authors:Donatella Senatra, C. Ziparo, Cecilia Gambi, and L. Lanzi
A water-in-oil microemulsion composed of water, AOT and decane with volume fraction φ=0.50 and molar ratio X=40.8 was analysed by DSC. The percolation and the bicontinuous transitions as well as the melting endotherms and the freezing
exotherms were measured. The main attention was focussed on the system energy balance. It was found that, by freezing the
samples after the occurrence of the percolative transition, the total heat released is significantly less than the heat absorbed
in the melting endotherms. A simple geometrical model was used as an analysis tool of the aforementioned energy difference.
Since the system studied exhibits a percolative transition of dynamic type, on approaching the percolation threshold temperature
(T≤Tp) and a static percolation for T≥Tp, the structural change from the connecting water-droplet-cluster to a connecting water channel was schematised in the model
as a change from a sphere-necklace to a water-cylindrical channel of equal volume and equal length. The surface energy associated
with the formation of the two different geometrical surfaces was evaluated and the amount of saved energy compared with the
experimentally measured one.
Authors:M. E. Brown, A. K. Galwey, and G. G. T. Guarini
The literature reveals that the mechanisms of some solid-state dehydrations are more complicated than has been generally accepted. Reactions at a thin advancing reactant-product interface provide the geometric models on which the most widely employed rate equations are based. For some systems, this “thin interface” model is a simplification of observed behaviour. Elimination of water from crystallographic sites may occur to a significant extent within a much thicker zone of reactant towards which the active interface is progressing. Consequently the region of chemical change may not coincide with the region of structural transformation. Limited initial dehydration may occur across all crystal faces prior to the onset of a nucleation and growth process that is usually regarded as the dominant rate process in the dehydrations of many large crystals. Experimental observations for solid-state dehydrations are discussed and reaction mechanisms with different rate controlling processes are distinguished. Studies of dehydrations have contributed substantially to the theory of solid-state reactivity, and advances in understanding may have wider application to other solid-state reactants.