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This paper reviews the experimental work conducted at the physicochemical workstation of the Novosibirsk free electron laser (FEL) since 2005 on developing methods for studying the fractional composition of nanoobjects of different nature. It has been found that the submillimeter radiation of the FEL leads to soft ablation of biological macromolecules. Furthermore, the molecules are transferred to the aerosol phase separately, each type of molecules forms its own fraction of aerosol nanoparticles without destruction and denaturation, and their sizes correlate with molecular weight. It is suggested that submillimeter laser ablation can be used to determine the sizes of nanoobjects of different origin. The paper discusses the results of experiments with mineral clusters, nanopowders, synthetic and biological polymers carried out using traditional methods of investigation of the fractional composition of nanoscale materials (atomic force microscopy, scanning electron microscopy, dynamic light scattering, and x-ray diffractometry) and using the new method-the analysis of the aerosol products of submillimeter laser ablation. It is shown that submillimeter laser ablation with the subsequent registration of aerosol products by modern equipment is a versatile, simple, fast, and accurate method which can complement the above-mentioned methods.

Characteristics of a system of polarization-optical detection of a pulsed terahertz spectrometer in nonlinear crystals of zinc telluride (ZnTe) are considered. The influence of the ZnTe crystal thickness (0.5, 1, and 2 mm) on the detection system sensitivity is studied experimentally; a comparison with model calculations is performed. The effect of the time step and the interval of scanning of the terahertz pulse on the spectral resolution and range of the spectrometer is demonstrated experimentally and theoretically. Terahertz transmission spectra of typical container materials are measured.

Pulsed generation of terahertz radiation in GaAs, InAs, and InSb semiconductors under the action of femtosecond laser radiation at the wavelength of 775 nm is studied. The generation efficiency is shown to increase by a factor of 2.7 if InAs is placed into a magnetic field of 0.8 T. An increase in the generation efficiency by the mechanism of optical rectification in InAs samples with the 〈111〉 orientation is demonstrated.

The rate of data transfer through an optical communication channel with a photon counter based on an avalanche photodiode being used as a detector in this channel is studied. The rate of data transfer through the optical channel is found as a function of the reverse bias voltage of the photodiode, the optical signal power, and the threshold level of detection.

This paper considers the results of using a two-mirror multiple-beam reflection interferometer (RI) which has a response function in reflection similar to the response function of a Fabry-Perot interferometer in transmission. The two-mirror cavity of the RI included two flat mirrors, one of which was highly reflective, and the other had an asymmetric coefficient of reflection from different sides. The light reflected from the RI was brought to an optical fiber through a collimator lens. The optical fiber, collimator, and RI constituted an integrated fiber RI, which was first used for continuous tuning of the wavelength of an erbium ring fiber laser with a continuous generation in the spectral range 1520-1566 nm.

This paper analyzes the effect of changes in the key parameters of an algorithm for identifying cracks in images of rolls of continuous casting machines. The effects of the background threshold of binary conversion and the filter kernel size on the total error of calculations of geometric characteristics of cracks are considered. The range of crack lengths for which the developed algorithm is suitable is calculated based on experimental data.

It is noted that, in many cases, object control is performed under conditions of a prior uncertainty in external actions and uncertainty in the current state of the object. Guaranteed methods are described which provide quantitative estimates of the boundaries of all possible phase states of a system taking into account all actions. Examples of calculations of inclusions of reachable sets are given

An analysis is made of the effect of zeros and poles of a closed-loop automatic control system on its direct measures of performance: overcontrol and control time. The necessity of determining the dominant poles in the root-locus plane is shown. A criterion for the ε-dominance of the components of the transient function of automatic control system is presented. A method for calculating direct measures of performance based on the location of zeros and poles of the system is developed. Numerical examples are considered.

The structure, operation logic, and hardware tools of the control system of a linear induction accelerator for an X-ray complex are considered. The hardware developed in the CompactPCI standard for the control system is described. The possibility of embedding of smart microelectronic equipment into high-voltage elements of the facility is analyzed.

The functional structure of typical representatives of intelligent systems is considered in relation to technological control objects. A generalized structure of intelligent control systems is developed. The proposed approach was instantiated for specific processes.