Reactions to geovisualization: An experience from a European project

The paper is written jointly by two parties, computer scientists specializing in geovisualization and experts in forestry, who cooperated within a joint project. The authors tell a story about an attempt of the geovisualizers to introduce the foresters to the concept and principles of exploratory data analysis and to the use of visualization for systematic and comprehensive data exploration. This endeavor should be considered as an informal experiment rather than a rigorous scientific study. Unlike customary tests of the usability of specific tools and techniques, the geovisualizers did not give the forestry specialists a series of tasks to carry out by applying geovisualization tools and did not try to measure how well the foresters performed. The idea of the geovisualizers was to demonstrate the principles and power of exploratory data analysis to the foresters by example. For this purpose, the geovisualizers performed an exploration of a non‐trivial data set by themselves and reported the procedure, the principles, the techniques, and the findings to the foresters. The reaction of the foresters uncovered a range of fundamental issues that are relevant to geovisualization and information visualization research. The authors analyze these issues from their perspectives and formulate a set of questions which researchers in geovisualization should be asking

Исследование режимов работы токопроводов в системах питания кранов с индукционной подпиткой с учётом влияния высших гармоник тока

Purpose. Investigation of the influence of higher harmonics of current on current distribution, voltage and power losses in the supply systems of crane trolleys and development of a calculation method for practical use. Methodology. The analytical method and the results of the modeling method were used for research. Results. Analytical relationships have been obtained that make it possible to determine the current distribution, voltage and power losses in the systems of induction feeding of crane trolleys, taking into account the composition and amplitude of the higher harmonics of the current. Originality. For the first time, analytical dependences are obtained that take into account the effect of changing the trolley parameters on the frequency in the feed systems. Numerical values have been determined for the most commonly used induction feed systems for cranes. It is shown that with an increase in the cross-section of the feed bar there is a decrease in the main, and especially additional, losses. Practical value. Theoretical relationships have been obtained that can be used to calculate the optimization of induction feed systems in the presence of higher harmonic currents arising in power systems during operation of crane semiconductor controlled electric drives.У статті викладена методика розрахунку розподілу струму по струмопроводам, втрат напруги і потужності з урахуванням вищих гармонік струму в системах живлення кранів з індукційним підживленням. Отримані необхідні аналітичні залежності, що пов’язують параметри струмопроводів з відносними значеннями частоти вищих гармонійних і визначають їх вплив на струморозподіл, втрати напруги та потужності. Показано, що зі збільшенням перетину шин підживлення відбувається зниження втрат напруги і додаткових втрат, в тому числі і від струмів вищих гармонік, за рахунок перерозподілу цих струмів і втрат від них в шину подачі, що має практично незалежний від частоти активний опір. Показано, що основна частина додаткових втрат визначається амплітудами гармонік з порядком n≤7. Методика може бути застосована для систем живлення залізничного транспорту і розподільних систем, виконаних з застосуванням сталемідних і сталеалюмінієвих струмопроводів

Liquid crystal director fluctuations and surface anchoring by molecular simulation

We propose a simple and reliable method to measure the liquid crystal surface anchoring strength by molecular simulation. The method is based on the measurement of the long-range fluctuation modes of the director in confined geometry. As an example, molecular simulations of a liquid crystal in slab geometry between parallel walls with homeotropic anchoring have been carried out using the Monte Carlo technique. By studying different slab thicknesses, we are able to calculate separately the position of the elastic boundary condition, and the extrapolation length

Fractal formation and ordering in random sequential adsorption

We reveal the fractal nature of patterns arising in random sequential adsorption of particles with continuum power-law size distribution, $P(R)\sim R^{\alpha-1}$, $R \le R_{\rm max}$. We find that the patterns become more and more ordered as $\alpha$ increases, and that the Apollonian packing is obtained at $\alpha \to \infty$ limit. We introduce the entropy production rate as a quantitative criteria of regularity and observe a transition from an irregular regime of the pattern formation to a regular one. We develop a scaling theory that relates kinetic and structural properties of the system.Comment: 4 pages, RevTex, 4 postscript figures. To appear in Phys.Rev.Let

Transformations Functioning in the Spanish Translation of I. Bunin’s Story “The Beauty”

В работе подробно анализируются переводческие трансформации, использованные при переводе рассказа И. Бунина «Красавица» на испанский язык (замены, перестановки, добавления и т. д.), определяются факторы, влияющие на выбор именно этих переводческих решений.The research analyzes in detail the translation transformations used in the Spanish translation of I. Bunin’s story “The Beauty” (substitutions, permutations, additions, etc.) and determines the factors influencing the choice of these translation solutions

Liquid crystal anchoring transitions on aligning substrates processed by plasma beam

We observe a sequence of the anchoring transitions in nematic liquid crystals (NLC) sandwiched between the hydrophobic polyimide substrates treated with the plasma beam. There is a pronounced continuous transition from homeotropic to low tilted (nearly planar) alignment with the easy axis parallel to the incidence plane of the plasma beam (the zenithal transition) that takes place as the exposure dose increases. In NLC with positive dielectric anisotropy, a further increase in the exposure dose results in in-plane reorientation of the easy axis by 90 degrees (the azimuthal transition). This transition occurs through the two-fold degenerated alignment characteristic for the second order anchoring transitions. In contrast to critical behavior of anchoring, the contact angle of NLC and water on the treated substrates monotonically declines with the exposure dose. It follows that the surface concentration of hydrophobic chains decreases continuously. The anchoring transitions under consideration are qualitatively interpreted by using a simple phenomenological model of competing easy axes which is studied by analyzing anchoring diagrams of the generalized polar and non-polar anchoring models.Comment: revtex4, 18 pages, 10 figure

Energy-Saving Vibration Impulse Coal Degradation at Finely Dispersed Coal-Water Slurry Preparation

Theoretical and experimental research results of processes of finely dispersed coal-water slurry preparation for further generation of energetic gas in direct flow and vortex gas generator plants have been presented. It has been stated that frequency parameters of parabolic vibration impulse mill influence degradation degree. Pressure influence on coal parameters in grinding cavity has been proven. Experimental researches have proven efficiency of vibration impulse mill with unbalanced mass vibrator generator development. Conditions of development on intergranular walls of coal cracks have been defined

Polydisperse Adsorption: Pattern Formation Kinetics, Fractal Properties, and Transition to Order

We investigate the process of random sequential adsorption of polydisperse particles whose size distribution exhibits a power-law dependence in the small size limit, $P(R)\sim R^{\alpha-1}$. We reveal a relation between pattern formation kinetics and structural properties of arising patterns. We propose a mean-field theory which provides a fair description for sufficiently small $\alpha$. When $\alpha \to \infty$, highly ordered structures locally identical to the Apollonian packing are formed. We introduce a quantitative criterion of the regularity of the pattern formation process. When $\alpha \gg 1$, a sharp transition from irregular to regular pattern formation regime is found to occur near the jamming coverage of standard random sequential adsorption with monodisperse size distribution.Comment: 8 pages, LaTeX, 5 figures, to appear in Phys.Rev.