An iterative approach to solving the inverse kinematic problem with optimized choice of the initial approximation is proposed. The investigation is important for acoustic, optical, and seismic tomography in the conditions of geometric optics approximation.
Amounts of calculations intended for implementing various algorithms of cone-beam 3D tomography reconstruction are analyzed. A technically simple way of spiral scanning meeting the requirement of completeness condition is considered. Methods for reducing the amount of calculations by considering only the necessary part of projection data for object reconstruction at a specific point and by eliminating calculation of the beam index in the reciprocal projection are proposed. A method for modeling the cone-beam tomography process is illustrated using the proposed algorithm.
An approach to constructing specialized Internet portals is considered. These portals have to ensure access to knowledge and information resources of a certain field of knowledge. The information basis for such portals is formed by ontologies, which allow heterogeneous data and knowledge to be presented in a unified manner and ensure their relatedness. For simpler customization of the portal to a chosen field of knowledge, its ontology is divided into the base ontologies (ontologies of research activities and knowledge) independent of the knowledge domain of the portal and the domain-related ontology, which describes a certain field of knowledge. Based on the portal ontology, internal storages of data are constructed; management of information content, navigation and search in the information space of the portal are organized.
A method for digital stroboscopic holographic interferometry of focused images for measuring points of displacements of a metal plate vibrating at a resonant frequency is considered. Unlike classical holographic interferometry, in this method, the measurement process does not include the process of interferogram obtaining, recording, and interpretation.
M. V. Fursa Institute of Physical and Technical Information Science, Protvino, Russia
Fraunhofer Institute of Media Communication, St. Augustin, Germany E-mail: zyx@go.ru
Pages: 88-94
The problem of creating exact 3D models of complex real objects for virtual reality applications is considered. One of the systems reconstructing 3D coordinates of a scene from its 2D image by means of structured illumination is presented. Problems related with system operation and leading to reconstruction errors are described. A new method is proposed for improving performance of the system due to considering optical distortions and using several images for reconstructing the same scene area.
V. G. Khoroshevskya and V. A. Pavskyb aA. V. Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, E-mail: khor@isp.nsc.ru bTechnological Institute of the Food Industry, Kemerovo, Russia E-mail: pavvm@kemtipp.ru
Pages: 95-104
An approach to simplifying the calculation of efficiency indices of distributed computer system functioning is described. The approach makes it possible to derive, in terms of uniform methodology, equations for calculating probabilities of states as well as moments (initial and central) of arbitrary order for system transient functioning. Results of numerical analyzing the functioning efficiency of massively parallel processing computer systems are presented.
D. E. Denk
Institute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, E-mail: dima@iae.nsk.su
Pages: 105-110
The errors of quadrature signal interpolation are analyzed. Quantitative assessment of the noise effect and the quadrature signal distortion is given. A method for estimating the accuracy of quadrature output sensors is proposed.
P. S. Zavyalov, Yu. A. Lemeshko, L. V. Finogenov, and Yu. V. Chugui
Technological Design Institute of Scientific Instrument Engineering, Siberian Branch Russian Academy of Sciences, Novosibirsk, Russia E-mail: chugui@tdisie.nsc.ru
Pages: 111-117
The method for inspecting grid spacers (GSs) using diffractive optical elements is considered. Synthesis of diffractive elements, calculation of projecting optics, and also adjustment and calibration of the measurement system are presented. Methods for processing images obtained on different GS elements are described.
a:2:{s:4:"TEXT";s:124:"S. M. Borzova, S. T. Vaskova†, O. I. Potaturkina,b, and Zh. O. Sheishenova";s:4:"TYPE";s:4:"html";} aInstitute of Automation and Electrometry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia E-mail: borzov@iae.nsk.su bNovosibirsk State University, Novosibirsk, Russia
Pages: 118-124
A problem of tongue-selective diagnostics of the burning process in multiburner research and industrial installations is considered. The main factors that govern the response of optical sensors and gas analyzers to changing processes in the chamber as a result of fuel redistribution are determined. A simulation model of the object investigated is created. The model takes into account the determined dependences. A tongue-selective combustion diagnostics algorithm based on the developed model is proposed and demonstrated.
Results of applying domain engineering technologies to the development of distributed measurement systems are reviewed. An ontology of the subject domain
