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The algorithm of formation to structure of self-regulating technical system, optimum on Pareto, which quality is defined by the plan of measurements from agents, on the basis of kvalikativny functions is considered.
Modern approaches to the creation of expert systems were considered. Also, the main prospects for the development of expert systems that work on the basis of neural networks were considered.
A technique and algorithms for early detection of the started attack and subsequent blocking of malicious traffic are proposed. The primary separation of mixed traffic into trustworthy and malicious traffic was carried out using cluster analysis. Classification of newly arrived requests was done using different classifiers with the help of received training samples and developed success criteria.
The current state of the problem of distributed attacks aimed at denial of service is investigated, the last DDoS attacks are monitored. The most popular type of DDoS attacks continues to be httpflood. The modern methods of diagnosing DDoS-attacks are investigated. Positive and negative aspects of these methods were identified.
Methods and software were developed for studying parameters of frequency dispersion for radio links of different length. We used SDR based sounding system for studying a HF radio channel and determining parameters of frequency dispersion. The software component was implemented using licensed software Lab VIEW. The hardware component was implemented using a programmable transceiver USRP N210. We studied...
Silicon carbide field emission arrays coated with two different type of nanocrystalline diamond thin film: undoped and highly boron-doped are compared. The last one shows two times lower electric field threshold for electron emission.
The problem of increasing the efficiency of data transmission through a HF radio channel in the case of using passive sounding was studied. The paper presents the main characteristics of the stochastic radio channel with scattering (delay spread, Doppler spread and the signal-to-noise ratio) and communication modem, which have an impact on the efficiency of a communication system. Algorithm for estimating...
Terbium garnet single crystals (terbium gallium garnet, TGG, and terbium-scandium gallium garnet, TSAG) combine relatively high Verdet constant, low absorption coefficient, high thermal conductivity and high optical quality. The combination of properties leads to TGG being the most popular magneto-optic material at high-power applications for creation compact and efficient optical rotators and isolators...
The use of thin disk active elements [1] leads to essential decrease in negative influence of the thermal distortions on the output parameters of solid-state lasers. We may increase the output power from the single disk without suffering from thermal distortion while using the multi beam pumping. The purpose of our work was the realization of phase synchronization of several laser channels with a...
The resistance of the BJT collector layer can be sharply reduced by the effective injection of minority carriers (holes) from base to collector. The conditions under which this process can occur are the short rise time and the high amplitude of the base pulse.
This article describes the design principles of optoelectronic system (OES) for instantaneous frequency measurement (IFM) of microwave signals based on the use of amplitude-phase modulation conversion of single optical carrier into symmetrical dual-frequency signal for additional frequency separation, its modulation by unknown frequency and subsequent “frequency-amplitude” measurement conversion in...
The cause-effect relations between the levels of pulsations of the antenna system, caused by main rotor rotating of the helicopter, and the probability of the bit error occurring in the digital data transmission channels were established. Graph-analytical method of error probability estimation was developed.
This paper studies the phenomenon of joint generation of terahertz (THz) and X-ray radiation in the argon nanocluster jet under the action of high-power femtosecond laser pulse in both the single-color and dual-color regimes. It was discovered that in a gas cluster beam the pulse duration affects the properties of THz and X-ray emission differently. For the same given total energy of optical pulse...
The paper is devoted to the critical analysis of the pseudo-random number generators (PRNG) classification. The conclusion about the need to review the existing classification is done. It is shown that in addition to the traditional Feistel's Network «Square» and «Cube» must be considered, as well as hybrid architecture using Feistel's Network which round function is realized according to the scheme...
For analysis of power consumption of resistance spot welding systems field-circuit modelling is required. It includes both 2D eddy-current FEA analysis for estimation of the leakage impedance of transformer and P-Spice program for the circuit simulation. It is shown that the design of the transformer influences on the output current and power consumption. We used the equivalent circuit of three-winding...
The paper proposes an original equivalent circuit of the multiwinding transformer based on the classical theory of transformers and the introduction of a new parameter — the mutual inductance on leakage fluxes. The results of the calculation of currents and losses in the windings of a powerful toroidal transformer on the base of the original equivalent circuit of the multiwinding transformer are confirmed...
Review on latest modification applied to chemical composition of PTR glass was made. Advancements of updated chemical composition of PTR glass was shown in comparison with commercially produced glass. Such properties as refractive index change, optimal exposition and optical losses in visible range for the glass with recorded hologram was studied. In work samples of two chemical compositions were...
Strong dependency of hot electron yield and energies in relativistic laser-plasma interaction on the pre-plasma properties is demonstrated. Experimental data and numerical simulation results are presented.
The angle measurement system intended for measuring angles between some directions set in the space by reflectors is presented in the report. The system operates by continuous rotation of platform with the autocollimating null-indicator and the ring laser or the holographic optical encoder.
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