Vol 13, No 1 (2015)

From the perspective of modern physics semiconductors represent the plasma, fully ionizer zed, but on average, electrically neutral gas. Semiconductor plasma has a number of specific ski features compared with gaseous plasma. First of all, the possibility of existence at very low temperatures down to absolute zero and a high concentration of particles. Moreover, this electrodynamic environment has properties of high-pass filter. In this paper, based on the trim account of the differential equation for the reflection coefficient was able to obtain the frequency characteristics of attenuation for inhomogeneous plasma layers at different angles of incidence of the electromagnetic wave. The problem for the homogeneous layer at various angles of incidence of the wave, as well as for the parabolic and linear layers with different angle of incidence of the polarized wave. The analysis of the frequency characteristics of attenuation in the passband, and lane keeping. It is shown that the design of microwave filters range it is best to use a frequency characteristic of the attenuation introduced by the semiconductor layer of plasma with a parabolic profile of the electron concentration. This characteristic has a large slew rate, transition region, compared with a linear profile, and less attenuation in the passband, compared with a uniform profile

Acousto-optic switch can route optical signals in a branched fiber-optical network providing the input optical fiber switching to the output fiber-optic array. The principle of its work is based on light beam diffraction by ultrasonic wave, created in optically transparent media. The refractive index of an optical medium is altered by the sound frequency. Based on the acousto-optic deflector properties analysis, expressions defining acousto-optic switch capacity and switching time are deduced. Acousto-optic switch capacity is the number of switching channels, which are determined by the acousto-optic deflector resolution, namely the number of distinct light point in space, which provides the deflector at a discrete sound frequency change. The number of distinct points is determined by maximum angular range and the Rayleigh criterion - minimum angular intervals wherein two light points will be visible. Linking resolution characteristics and acousto-optic deflector parameters we obtained that the acousto-optic switch capacity is determined by the acousto-optic deflector aperture, the sound wave velocity, and the frequency operating range. The optical signal can’t be transmitted in less time than the acoustic wave travel through the solid media of the acousto-optic deflector. Therefore, the switching time is the value for which the acoustic wave passes through the optical field in the transverse direction.

This paper describes the development of a software module for the simulation of communication systems with dynamic network topology. Developed module allows you to explore the effect of moving the network nodes on the quality of the transmitted information. With the help of the developed module the work of the communication system with dynamic network topology is analyzed. Simulation time is 2 to 6 hours. Transfer rate facilities ranged from 20 to 80 kmph. The data transfer rate was from 0.5 to 32 mbps. The experimental results show that the network is suitable for the provision of real-time traffic services (as online application) and data traffic by condition end2end delay of packet. By condition, the probability of packet loss this communication system suitable for the transmission of real-time traffic and for normal data traffic requires the use of a transport layer protocol that guarantees delivery of data packets, as TCP. Investigate methods for increase the coverage area of public communication systems can be used to provide Internet access to transport facilities such as river vessel, railway train or road transport, as buses or cargo vehicular.

For today the majority data networks are working on technology Ethernet, and used in a ring topology, thereby allowing optimal network reliability. Most of the equipment of such networks is access switches having from 8 to 48 ports for connecting subscribers. Such switches usually only work with frames, that is level 2 model OSI. But such a construction, in addition to simplicity, reliability and low cost, has its drawbacks, such as the possibility of Ethernet storms that can bring the entire network. The process of storms underlies at technology of Ethernet, namely in the absence of the removal mechanism of broadcast frames from the exclusive network. Consequently, this technology does not allow the existence of more than one communication switching channel between the two points exchanging information. For protection from storms special protocols to block redundant switching channels between the communications equipment are used. There are quite a lot of such protocols today, such as STP, PVSTP, RSTP, but the most common is MSTP. But they all have the same function, based on the finding of redundant channels of communication between the two switches. In finding happens, block all but one, selected on the basis of comparison of parameters based on the coefficients dependent on the bandwidth of the channel. Thereby, there is prohibition of the transmission of traffic on all channels except the selected one. Based on the basic principle these protocols impose restrictions on the use of all possible communication channels. This approach results in an inefficient allocation of all available bandwidth in the network. To solve this problem, we developed an algorithm that gives an opportunity to use all available network bandwidth, if it needs, without affecting to the quality of service for existing subscribers. Our algorithm uses the built-in mechanisms in existing protocols, thereby it allows at low changes improving the efficiency of the network to be almost doubled.

The ways of practical scientific knowledge application in the complex systems science (CS) of organizational and technical (holonic) type are discussed in the article. Consumers of scientific knowledge are the decision makers (DM): they are managers, experts and other specialists in business management. The purpose of the first method is an information exchange between decision-makers through publications (theses, monographs, articles, essays, research papers). In the article, the fields related to information exchange conventionally are called the dissertation science. The purpose of the second method is technical progress, aimed at innovation in the field of business. Knowledge related to technological progress is called innovative knowledge in this article, and the area of science associated with them is innovative science. Decision-makers in the management of the CS used two kinds of knowledge: verified and axiological. Verified knowledge is the result of research. They are objective, repeatedly tested and widely known. Cost of verified knowledge equals to the price of training DM. Axiological knowledge is subjective and unique, known for a wide range of decision-makers (or even a single person). They have a contractual commercial price that is equal to their cost of risk. Innovations are novelties dramatically improving the work of the CS. Effective innovations related to the axiological knowledge at the stage of successful verification - they are called innovative knowledge. The article describes the features of the use of verified and axiological knowledge in dissertation and innovative science. Criticism of modern quackery, which plays an important role in both cases, is presented in the article.

In the article is inspected the antenna on the basis of magnetized gyromagnetic resonator (GR). Antenna consists of the feeder line, the magnetizing coil, volumetric disk resonator and spherical gyromagnetic resonator (YIG). Magnetized gyromagnetic resonator is excited through the feeder line microwave field and then, in turn, excites the volume resonator (RR), which radiates into the space of the electromagnetic field of a rotating polarization. Moreover, the coefficient of ellipticity of the radiation field is close to unity in the radiation direction. This emitter has a number of unique properties, which are provided by magnetized GR: radiation field circular polarization; electric switching on-Board rotation, high frequency selectivity and the magnetic reconstruction of the Central frequency radiation-treatment. The direction of rotation of the vector field is due to the switching of the current in the electromagnetic-Nita. The shift of the Central frequency of the radiation can be produced by changing the current in padminidevi-ing the spool of wire. In the axial direction, the coefficient of ellipticity of the radiation field is close to the unit-n. Experimental measurements of antenna parameters are on the basis of magnetized GR. In the article the analysis of characteristics of the antenna on the gyromagnetic resonator with different types of open volume roadways resonators are studied. We investigated the ER with a metal disk on the basis of dielectric and ferrite substrate, a ring radiator on a ferrite substrate and the PR type «glass». Antenna with some types of EOS provides a higher gain (RR type «glass»), others close to one of the coefficients are consistent with a person of the ellipticity (disk OR on a ferrite substrate). In more detail, polarization characteristics of the antenna are important for the creation of the probes and modulators of the ellipticity of the radiation. The curves of the dependence of the ellipticity coefficient in space and formulae for calculation of the characteristics of antennas based magnetized GR. The calculated and experimental data is close enough match.

The aim of this work is to develop a steganographic algorithm, which is able to organize covert channel data in terms of a targeted attack on a container. Robust against an active attack on a steganographic algorithms is used to solve a number of applied problems. For example, the task of adding a new functionality to a fixed format. It is proposed to use the state diagram to describe the possible transformations of a digital object as a result of the attacks. The transition between the two states is characterized by the distortion introduced in the original object, and if the distortion produces a number of different objects, the corresponding state in the diagram is marked with infinity symbolizes sign which the attitude of "one-to-many". Thus, the problem of constructing robust against an active attack steganography is reduced to obtaining an algorithm that is able to extract hidden information from all the states in the diagram. There are two theoretical methods of construction robust against an active attack steganography: method of reducing a plurality of containers and method of assessing distortion. The first method is based on the assumption that among a plurality of containers. There can be such containers that the attack does not destroy embedded information. The second method allows you to build a robust embedding algorithm if the distortion introduced by the attack is limited by modulo in a metric space of containers. This paper gives a practical application of the proposed methods for the construction of steganography system that is robust against conversion of color images to grayscale. The program implementation in the programming language Python is given.

The problems of cryptography and steganography are taught at two universities - PGUTI (Samara) and the University of Shumen (Bulgaria) on basis of scientific cooperation agreement. It is a brief overview of the initial course content of "Informatics" in PSUTI. The course teaches students to learn the basic concepts of computer science and get a first glimpse of data protection methods of cryptography and steganography. There are basic ideas of published works. The first work on steganography in PSUTI were published in 2002. A few original ideas are described. For example, in the cryptosystem manage operations in addition to the exclusive-OR is used to encrypt the logical equivalence of the operation, as well as arithmetic operations of addition and subtraction. Another cryptosystem uses a secure communication protocol TCP / IP. Thus there is a deliberate change in the length of the transmitted packets. In Shumen University since 2004 cryptography and steganography are studied in several disciplines for students of «Safety Management» and «Computer Science». In 2010, the Faculty of Mathematics and Informatics in Bulgaria introduced the course «Computer Steganography» for the first time. Research on steganology was conducted by the scientific research Laboratory «Computer Security», which was developed by the cluster computer system with a total capacity of 180 GFLOPS and the energy efficiency of 19 MFLOPS / Watt. According to the study conducted by the teachers together with students at two universities, several monographs and textbooks have been published as well as articles in scientific and technical journals, more than 70 scientific papers were presented at scientific conferences, the patents were received, a number of theses have been prepared and defended. An agreement on creative collaboration was concluded between PSUTI and SHU universities.