Vol 13, No 3 (2015)

This work presents description of self-consistency method for solution interior electrodynamics problem concerned on distribution of current over surface of microstrip antenna based on chiral substrate. Requirements to physical model of microstrip antenna radiator were formulated. We represent derivation of elements of surface impedance matrix and elements of input admittance matrix for chiral layer where right-handed helixes were considered as conductor dopants. Singular integral equation with a Cauchy kernel for computing current dencity over microstrip antenna surface was obtained, and numerical solution of this equation is a well-set mathematical problem

Transmission of one-off messages over busy telecommunication channels provides to equip by new features both installed analogue and IP-telephony systems. Maximal power of one-off messages should be estimated by taking into account telephone channel parameters and signal properties to minimize influence of one-off messages overlapping on the noise immunity of analogue and discrete data transmission systems. This work describes how to evaluate relation of energy characteristics of continues information and one-off messages transmitted over telecommunication channels. We carried out information analysis of voice signal components and noise immunity. Probability of data signal distortion due to impulse noise would be stay almost constant either with or without one-off messages, if one-off message power would be less data power, and error probability weakly depends on power of signal propagating over channel. Therefore condition h 2 > 9 should be provided to eliminate one-off message strong influence on validity of analogue and discrete data transmission for channels with low level fluctuation noise. Here parameter h 2 is power ratio of relevant data signal to one-off message signal. We propose to use broadband signal to improve one-off message selection. Permissible relations of power levels of continues information and one-off messages in the kind of voice signals were defined for their successful simultaneous transmission.

This work is concerned on problems of information exchange organization between the host computer and discrete signal remote and distributed input/output modules ADAM-4055 (Advantech Co., Ltd., Taiwan) over computer distributed control and data acquisition system. Here host computer and modules are joined by industrial network based on RS-485 interface by using ASCII or Modbus protocol. The problem of data input/output between host computer and ADAM-4000 modules based on industrial network is solved by command issuing by host and following receiving the response from addressable module. We considered command list used for operating with discrete signal input/output modules, analyzed their structure, and developed application providing any command input to ADAM-4055 module and response receiving and visualization.

We present developed model of diversified manufacturing complex operating as a part of macroeconomic system. Model involves main outline of circular of material and financial flows. It takes into account structural features of cross-sector relationships based on interindustry balance methodology. Model covers features of investment demand accumulating investment flows over entire macroeconomic system in the investment market. It also takes into account regulatory control of monetary management via money market and goods market under influence of market uncertainty effects. We produced business case experiments to research the influence of monetary policy actions on management of diversified manufacturing complex operation as a part of macroeconomic system. According to obtained results, money growth and interest rate reduction provide step up the rate of GDP under constraints due to effects of investment and liquidity traps. Business case approach application for research of diversified manufacturing complex operation dynamics based on simulation helps to reveal the cause-and-effect relationships and trends of diversified manufacturing complex development over set of unbalanced cases under undertrained conditions.

A new pulse shape filter and a planar monopole antenna for satisfying the ETSI mask requirements on UWB communication systems radiation levels are designed in the paper. The microstrip filter on the basis of Chebyshev type of the 11 th order is designed in the way that can transform any UWB noise-like signal to the one, fitting the 6 ÷ 8,5 GHz band of the ETSI mask. The total filter size is 27×16 mm 2. The UWB planar antenna configuration was constructed on the basis of fractal technology, that allowed to provide impedance matching in the band 3,09÷15 GHz, while remaining the small dimensions (34×41 mm 2), which are inherent to UWB band. Both devices are made from the same material and can be easily implemented on one printed circuit board, that will reduce loss and increase the efficiency of ETSI mask matching and electromagnetic compatibility with the existing wireless devices.

This work presents the main features of HF-band radio systems. Here generally MIMO technology is used for radio channel bandwidth enhancing. We propose to apply hybrid both spatial and polarization sub-channel spacing. The last one is realized by using three-orthogonal antenna elements forming a circular antenna array. We produced synthesis of eight-element circular antenna array and analyzed resulting model to define its electrodynamics properties. Results of numerical analysis are represented in the form of radiation patterns competed for vertical and horizontal sections over three HF-band frequencies. We produced analysis of capacity limits for MIMO 6x6 channel formed by proposed circular antenna array. According to obtained results, solutions based on circular antenna array provide channel bandwidth enhancing due to higher spatial selectivity and thereby improved signal-to-noise ratio.

Currently, the industry's creation of information, educational and entertainment content for audio information inquiries, movies and music are widely used spoken language. In this connection there is the problem of providing automatic control of the use of speech and in particular to prevent unauthorized actions with it. In many ways, this control is advantageously carried out in a secretive mode, where information about the processes of encoding and appropriate action available only to a specific group of persons. The authors have to solve this problem, we propose a method of adaptive hidden coding control information, providing for a given error probability of high secrecy. The method is to use the power properties of the voice data, the mathematical basis is used as an orthogonal basis of eigenvectors sub-band matrix instead of a pseudo-random sequence (PRS), which is widely used at present in the hidden coding control information. The studies found that the proposed method of sub-band projections has a higher level of secrecy of information control over the method of spreading since it causes less change in the proportion of the energy of speech segment data. Minimizing variations in energy band of the portion where the coding is not carried out, it is achieved through the use of sub-band projections found for sub-band matrix of eigenvectors whose eigenvalues are close to unity.

University automated information system is based on integration of data and advanced telecommunication infrastructure with great number of users (access subjects) with varied access rights to different data elements (access objects). Problem of minimization of information system user access privilege should be solved to provide effective corporate data protection. We present model of user access policy which joins restrictions of subject domain and capability access policy DBMS Oracle. Here restrictions of subject domain under permitted access are defined by user affiliation to hierarchy nodes that corresponds to university department organizing structure. Model provides flexible response to variation of user affiliation to nodes of university department hierarchy. It was implemented to Orenburg State University as a part of project "Orenburg State University Information Analysis System".

All GUI applications in UNIX environment require both graphic and data communication protocols, and these applications are interactive. That means if performance would be lower some threshold, users will mark them as unapplicable. Also there is a high performance threshold, when users will not be able to detect improvements under its growing. The problem of low performance network can be sold by graphic protocol compression. However this approach for the high performance networks does not work. For example, network transmits graphic command much faster then command is generated by application or faster then graphic server capabilities to receive and process them. Also there is a case, when application operates fast enough under current resources. Here user will miss all application improvements if application provides feedback at 100 ms, and compression would be inappropriate. However generally the network is a bottleneck, and both compute server and graphic sever have reserve cycles for graphic protocol compression. Graphic protocol is a machine language that provides for application program operating in the one computer to interact with graphics server operating in another computer. This work is devoted to problem of lab environment development for X11 graphic protocol analysis for research and following developing of method providing network traffic reducing between X-server and X-user.