Polarization holographic gratings in side-chain azobenzene polyesters with linear and circular photoanisotropy

We investigate thin phase polarization holographic gratings recorded with two waves with orthogonal linear polarizations in materials in which illumination with linearly/circularly polarized light gives rise to linear/circular birefringence. The theoretical analysis shows that the presence of circular photoanisot-ropy changes significantly the diffraction characteristics of the gratings. The intensities of the waves diffracted in the +1 and -1 orders of diffraction and their ratio depend substantially on the reconstructing-wave polarization. Experiments with films of side-chain liquid-crystalline azobenzene polyester that is a photoanisotropic material of the considered type confirm the unusual polarization properties. It is shown that polarization holography may be used for real-time simultaneous measurement of photoinduced linear and circular birefringence.     

Anomalies of Physical Properties inα-Bi2O3 — a Phase Transition Governed by the Electronic Mechanism?

A number of physical properties of -Bi₂O₃ was studied: the thermal expansion, thermally stimulated conductivity, electrical resistivity, and dielectric permeability. X-ray diffraction, DTA, and differential scanning calorimetry measurements were also carried out. Several anomalies were observed: a small maximum and drastic rise of the single crystal dielectric permeability, a sharp drop of the electric resistivity, a jump and change in sign of the thermally stimulated current, and an exothermal maximum in differential heat capacity. At the same time, the monoclinic lattice symmetry of -Bi₂O₃ was retained over the temperature range where these anomalies were found.     

Developing a software system for automata-based code generation

This paper is devoted to the development of the State Machine Generator system meant for automatic code generation based on the principles of automata-based programming. This system models program logic in terms of the finite-state automaton transition graph and generates program code on its basis. Basic functions of the developed software system and the mechanism of their implementation are described. This paper also proposes a new pattern for designing automaton programs. As an example, State Machine Generator is used to develop a bug tracker system for software testing.     

On stochastic linear programming problems with the quantile criterion

We study qualitative properties of a stochastic linear programming problem with quantile criterion for a wide class of distributions. We show convexity conditions for the criterion function with respect to the strategy, and continuity conditions with respect to the strategy and reliability level. We give sufficient conditions for the existence of a solution. We present a new algorithm for finding a guaranteeing solution of the problem, i.e., an admissible solution for which the quantile criterion function's value turns out to be close to optimal.     

Fast Lighting Independent Background Subtraction

This paper describes a simple method of fast background subtraction based upon disparity verification that is invariant to arbitrarily rapid run-time changes in illumination. Using two or more cameras, the method requires the off-line construction of disparity fields mapping the primary background images. At runtime, segmentation is performed by checking background image to each of the additional auxiliary color intensity values at corresponding pixels. If more than two cameras are available, more robust segmentation can be achieved and, in particular, the occlusion shadows can be generally eliminated as well. Because the method only assumes fixed background geometry, the technique allows for illumination variation at runtime. Since no disparity search is performed, the algorithm is easily implemented in real-time on conventional hardware.     

Particle positioning techniques for dusty plasma experiments

Video microscopy is a widely applied diagnostic to investigate the structure and the dynamics of particles in dusty plasmas. Reliable algorithms are required to accurately recover particle positions from the camera images. Here, four different particle positioning techniques have been tested on artificial and experimental data of dusty plasma situations. Two methods that rely on pixel-intensity thresholds were found to be strongly affected by pixel-locking errors and by noise. Two other methods-one applying spatial bandpass filters and the other fitting polynomials to the intensity pattern-yield subpixel resolution under various conditions. These two methods have been shown to be ideally suited to recover particle positions even from small-scale fluctuations that are used to derive the normal mode spectra of finite dust clusters.     

Computer aided comparative analysis of the binding modes of the adenosine receptor agonists for all known subtypes of adenosine receptors

Molecular models of all known subtypes (A1, A2A, A2B, and A3) of the human adenosine receptors were built in homology with bovine rhodopsin. These models include the transmembrane domain as well as all extracellular and intracellular hydrophilic loops and terminal domains. The molecular docking of adenosine and 46 selected derivatives was performed for each receptor subtype. A binding mode common for all studied agonists was proposed, and possible explanations for differences in the ligand activities were suggested.     

From the editors

Proceedings of the 7th International Conference on Pattern Recognition and Image Analysis: New Information Technologies (PRIA-7-2004)18–23 October, 2004, St. Petersburg, Russian Federation Revised papers

From the editors     

Superconductive toroidal solenoid of Tokamak-7

Conclusions Our tests have shown that the superconductive magnetic system of the T-7 unit is operative and that the main design and circuit features adopted on the basis of preliminary investigations are appropriate. In particular, it was shown that it is possible to use a hydraulic parallel joining of numerous sections without additional adjustment. The superconductive magnetic system could be efficiently cooled by liquid two-phase helium rather than by supercritical cold helium which was frequently discussed in the literature.The authors sincerely thank the friendly collective of engineers, designers, technicians, and workers who enthusiastically applied their efforts to the building of the Tokamak-7 unit and the execution of the tests.Translated from Atomnaya Énergiya, Vol. 45, No. 3, pp. 171–174, September, 1978.     

Experiments on the synthesis of neutron-deficient isotopes of kurchatovium in reactions with accelerated50Ti ions

Conclusions A number of conclusions can be drawn from the aggregate of experimental results.The method of synthesis of transfermium elements in the irradiation of lead isotopes with ions with mass A_I40 atomic units, investigated earlier [12] for the example of the reaction Pb(⁴⁰Ar, xn)Fm, is also extremely effective using⁵⁰Ti ions. The reactions Pb(⁴⁰Ar, 2n)Fm and Pb(⁵⁰Ti, 2n)Ku have approximately equal cross sections, which might have been expected on the basis of theoretical estimates. This permits us to hope that this method can be used successfully for the synthesis of heavier elements in the reactions induced by⁵⁴Cr,⁵⁵Mn, and⁵⁸Fe ions.In all probability, the substantial changes in the systematics of the half-lives for even-even isotopes of kurchatovium are associated with the structure of the barriers to fission of these nuclei. From this standpoint, it seems important to investigate the properties of more neutron-deficient isotopes of kurchatovium, using, in particular, the reactions with²⁰⁴Pb, and to attempt to advance into the region of elements with Z 106. On the other hand, a detailed theoretical analysis must be made of the data obtained on the basis of the modern theory of nuclear fission, which, in our opinion, will aid in a more reliable prediction of the properties of heavy and ultraheavy elements.Translated from Atomnaya Énergiya, Vol. 38, No. 6, pp. 382–390, June, 1975.