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The influence of the interferometer optical system characteristics on the distribution of spectral power density of partially coherent light passing through the system is investigated. The results of effective wavelength measurements for partially coherent light sources are presented. It is shown that the optical system transforms the spectra, which leads to a systematic error of interference measurements using the scattered light phase. With atomically smooth surfaces used as a reference mirror, the influence of this system on the phase distortion is investigated. The systematic error is found to be approximately 5 nm in terms of height owing to phase distortion. It is shown that the use of atomically smooth surfaces as a perfect measurement surface allows this error to be significantly reduced down to 0.12 nm. The results of measuring an echelon of atomic steps with a countable number of monoatomic layers on the silicon crystal surface are reported. The interatomic (interplane) distance in the crystal lattice of Si with orientation [111] is experimentally measured for the first time by low-coherence optical interferometry, and its value is found to be 3.145 0.003Å.

The unique variability of modern fiber and integrated optics and also the development of physics of complex nonlinear optical phenomena and nanophotonics have contributed to the development of qualitatively new approaches to the implementation and control of pulsed lasing in fiber lasers in the last decade. In this paper, we present a structured review and comparative analysis of current methods for static and dynamic control of the regimes and parameters of generation in mode-locked fiber lasers.

Modified holographic photopolymer materials developed at NIOCH SB RAS, which, as a result of post-processing, provide high diffraction efficiency with a small thickness of the recording layer, have been studied by the method of recording reflection and transmission volume elementary holograms. Samples of volume reflection holograms with a diffraction efficiency of about 90% are obtained with a recording layer thickness of about 6 μm and refractive index modulation ∆n of no less than 0.036. The obtained holograms have high transparency in the entire visible range of the spectrum, low shrinkage, and good uniformity of the spatial structure of the grating, as evidenced by a clear picture of the side lobes of the spectral response contour.

The method and the possibility of realizing isotropic Bessel-Hilbert diagnostics of the phase optical density fields of gaseous, condensed, and reacting media are discussed. The probing field in such systems is formed as a mono- or polychromatic configuration of the Bessel beams. The spatial-frequency Fourier spectrum of the Bessel beams is optically coupled with the concentric phase structure of the isotropic Hilbert filter, and the color structure corresponds to the spectral sensitivity of the photomatrix of a video camera connected to a computer, which analyzes the frame-by-frame sequence of the resulting images. The structure of such a probing field is resistant to diffraction disturbances induced by the medium under study and their influence on the isotropy of the Hilbert visualization of the phase optical density. The area of possible applications is experimental hydro and gas dynamics, thermal physics, oceanology, as well as the corresponding industrial technologies.

It is shown that the use of an ensemble of reading heads of a certain format, consistent with the parameters of the measuring raster and the matrix of indicator rasters in readheads, can significantly reduce the distorting effect of the systematic component of the instrumental error of the raster. It is noted that the specific technical solution considered in the present paper for matching the parameters of complementary lattice filters is not the only one for the raster used.

The results of experiments aimed at studying the concentration dependences and the time and temperature stability of the quadratic response of guest-host type materials based on polycarbonate and original synthesized dyes are presented. It is shown that modifications of the chromophore by dendronic side substituents significantly improve the solubility, which allows construction of polymer materials with a high content of optically active particles. The materials have high time and temperature stability and exhibit d₃₃ up to 80 pm/V at a chromophore concentration of 2.5^.10²⁰ cm^-3.

The main approaches to identifying the contours of objects in hyperspectral images are considered. Algorithms for extracting the contours of spectrally selective objects based on the spatial spectral correlation and interspectral difference of gradients are presented. The efficiency of the proposed algorithms for processing real hyperspectral images under the condition of additive Gaussian noise is demonstrated.

The paper is devoted to solving the problem of constructing a state estimation of a finite discrete-time Markov chain. A Markov chain is considered as a linear dynamic system with incomplete state information. The state estimation is based on the Luenberger observer. The conditions for state estimation invariance to perturbations of transition probabilities in a Markov chain are obtained. A numerical example is considered.

The first note about the outbreaks of the Siberian moth Dendrolimus sibiricus Tschetv. (Lepidoptera, Lasiocampidae) was published 125 years ago. The pest outbreaks of the 1950s and 1960s are poorly documented in Krasnoyarsk Krai. For the first time we provide the details of planning, organizing and implementing large-scale measures to combat the Siberian moth outbreak in the second half of the 1960s. The outbreaks that occurred in the southern taiga forests of the region covered an area of 260 thousand hectares. The maximal insect density reached 7 thousand caterpillars per one fir tree. The outbreak was successfully suppressed thanks to its early prediction, development and implementation of surveillance methods, as well as methods of aerial treatment and assessment of efficiency of protection measures. In 1967-1969, the crews of 45 An-2 aircraft during 2.5 thousand flight hours treated more than 200 thousand hectares of the pest foci with the dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane solution. Over 1,100 people took part in the aeronautical work, including about 250 engineers and technicians. During the 1960s outbreak, the total labor costs for airborne combat with the Siberian moth exceeded 22.000 man-days. To control the Siberian moth, for the first time, high concentration of the insecticide was used, i. e. 20 % oil solution of DDT + hexachlorocyclohexane, with ultra-low consumption rates of working solutions (from 3 to 5 l/ha). The Siberian moth outbreak that occurred on in Krasnoyarsk Territory in the mid-1960s clearly demonstrated high importance of cooperation between scientists and forest protection practitioners. The joint work contributed to the initiation of a specialized institution - the Station (later the Center) of forest protection of the Krasnoyarsk Territory, which leaders in different years were the researchers from the V. N. Sukachev Institute of Forest Sib. Br. Rus. Acad. Sci.

The principles of organization in the forest protection system and the principles of decision-making in the tasks of carrying out protective measures are discussed. The problem of assessing costs and risks in the course of forest protection measures is considered. The functioning of a security service is better understood when viewed as an agent-principal system. In the «agent-principal» system, agency relations are established when one person - the principal or the owner (principal) - transfers certain rights to another person - the agent. In this case, the agent, in accordance with the contract concluded between them, is obliged to act in the interests of the principal in exchange for remuneration. The agent problem, well known in the contract theory of economic systems management, is that if the managing manager is not the owner (principal) of the control structure, then there is a mismatch between the management goals of the principal and the agent. Each of them - both the agent and the principal - has their own interests. The agent has its own interests, and he tends to follow the goals of the principal only to the extent that the contract encourages him to do so. In such a system, there is an uneven distribution of information between the agent and the principal. By analogy with such economic systems, the system of forest protection is considered, where the state or the region is the principal, and the heads of regional structures of the forest protection system have information about the state of the forest ecosystem and the right to make managerial decisions. The features of the functioning of such a system are discussed. The problem of decision-making when carrying out protective measures is considered. The main feature of the decision-making process when protecting a forest from an attack by insects is that there is a lag between the moment a decision is made to switch to protective measures and the moment when protective measures begin. A decision-making model that minimizes the risks of errors is considered. The proposed approach makes it possible to evaluate the efficiency of decision-making in forest protection tasks, depending on the management principles used. The optimal decision on carrying out protective measures will be while minimizing errors of the first and second genera and the risk of damage to the plantation. In the proposed decision-making model, the coefficients for a certain type of pest can be determined from long-term survey data, while as an indicator of the state of the population, it is possible to use not only the values of its density, but also other indicators.