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A two-stage method for adaptive traffic signal control based on an estimate of the predicted weighted traffic flow passing through an intersection is proposed. At the first stage, we estimate the travel time required for each vehicle to pass the intersection using an artificial neural network model and estimate the predicted traffic flow through the intersection for a given phase of the traffic signal cycle. At the second step, a weighted flow estimate is formed, which takes into account the waiting time of vehicles. The proposed method for choosing the traffic signal phase is based on maximizing the weighted traffic flow. The results of experimental studies allow us to conclude that the proposed approach outperforms the classical approaches and state-of-the-art methods of traffic signal control based on reinforcement learning.

The results of numerical simulation based on the Mie theory of the superresonance effect for a dielectric sphere with a low refractive index are presented. Water is used as a material of the mesoscale sphere. It is shown that not only the previously studied weakly dissipative mesoscale spheres made of a material with a “medium” (about 1.5) and high (more than 2) refractive index, but also a low one (about 1.3) support the high-order Fano resonance effect associated with internal Mie modes. In this case, the intensities of resonant peaks for both magnetic and electric fields in the vicinity of the poles of the sphere can reach extremely high values of the order of 10⁶-10⁷ for a water droplet with a Mie size parameter of about 70.

The effect of changes in the thermophysical properties of the molybdenum film during intermediate oxidation during laser ablation on the dimensional effect of track formation is investigated by numerical simulation. In accordance with the data obtained, the hypothesis explaining the reduction of the track width in the ablation zone of the film in comparison with the effective diameter of the laser beam is refined. It is shown that a specific change in the thermal conductivity coefficient of a substance at the time of oxidation has a significant effect on the distribution of the temperature field, expressed in narrowing of the characteristic of the temperature distribution over the film surface, which has not been previously considered. It is established that the change in the density, specific heat capacity, and thermal effect of the chemical reaction of molybdenum oxidation during film oxidation does not significantly affect the temperature distribution in the zone of exposure to the laser beam.

The features of formation of face images of extended absolutely slit objects with an arbitrary opening of holes are studied in a coherent-optical system. On the base of the constructive approximation of the spectra of spatial frequencies (Fraunhofer diffractional patterns) of objects with different dimensions of front and back apertures, formulas for the field in the image of the front face are obtained and analyzed. Cases of objects with significantly expanding and significantly narrowing apertures of an extended hole (the differences in aperture sizes are much larger than the size of the Fresnel zone) are investigated in detail. It is found that the image structure of faces depends on the type of the opening. With a positive opening, where the back face is in the shadow region, the field at the output of the system corresponds to the image of the front face; with a negative opening, the image of the back face is observed. It is shown that error of determination of boundaries in the image of the active face of the object is inversely proportional to the square of the aperture difference. The invariant properties of the projection system for forming images of external faces of extended holes with an arbitrary opening are analyzed.

Design principles for the implementation of an infrared microscope registering the intrinsic thermal radiation of objects are considered. The infrared microscope temperature resolution, depending on the optical system parameters, design and photoelectric parameters of multielement infrared focal plane arrays (IR FPAs) are analyzed.

The paper presents experimental and theoretical study of crystal nucleation and growth in aluminum and structure development in the aluminum melt after the introduction of a cubic-shaped nanoparticle modifier and using the electron-beam surface treatment method. The output of this study is the rate of solid phase nucleation as a function of TiCN nanoparticle size dispersed in molten aluminum. The numerical simulation of crystal structure growth for a sample of AlSi12Cu2NiMg alloy treated by electron beam was performed using the MAGMASOFT computer code.

The mechanisms of excitation of low-frequency unstable combustion of a methane-air mixture in full-scale low-emission combustion chambers are experimentally studied. Experimental investigations of the flow characteristics without combustion in low-emission combustion chambers shows that the central zone of reverse flows can serve as a source of regular hydrodynamic pressure oscillations in a wide range of flow regimes. A model of low-frequency unstable combustion is proposed. The model is based on hydrodynamic instability of the flow in the central zone of reverse flows, which can excite low-frequency regimes of unstable combustion. Methods for suppressing thermohydrodynamic instability of combustion are developed. Based on the proposed model and with the use of methods that ensure suppression of combustion instability, a low-emission combustion chamber with a stable process of combustion in the entire range of its operation conditions is created and tested, which confirms the feasibility of the proposed approach.

An increase in the rate of combustion (gasification) of solid propellants exposed to a sufficiently intense blowing gas flow was discovered experimentally in the 1940s and called erosive burning. Later it was found that for some propellants at relatively low blowing speeds, there may be a decrease in the burning rate, called negative erosion. Attempts to theoretically study negative erosion have been made since 1971 and focused on analyzing changes in the intensity of heat transfer on a burning surface with the leading role of gas-phase reactions, taking into account the effect of large-scale fluctuations in gas velocity and temperature, the effect of the differences in diffusion coefficients and thermal diffusivity of the gas, and the effect of flame stretching. This paper presents an analysis of propellant combustion under blowing conditions in the presence of intense subsurface heat release due to exothermic reactions in the condensed phase. In the case where the surface temperature is limited by the boiling point, local temperature maxima can form in the subsurface layer, leading to an uneven response on the surface and to the occurrence of “intrinsic” turbulence in the adjacent gas layer. This turbulence leads to a change in the heat input to the propellant and allows one to qualitatively explain the effect of negative erosion.

The propagation of a high-temperature synthesis wave through a perforated metal plate mounted inside a cylindrical sample of a powder mixture of Ni + Al was studied experimentally and theoretically. Copper and steel plates of different thickness were used. The passage of the exothermic reaction front through a hole in the barrier was investigated for different thermophysical characteristics of the plate and different geometric dimensions of the hole. Depending on the parameters of the plate, the minimum critical diameter of the hole required for the propagation of the combustion wave in the sample was determined as a function of plate parameters.

The influence of mechanical activation (MA) and Mn content on the rate and maximum combustion temperature, sample elongation during combustion, size of composite particles, mixture yield after MA, phase composition, and morphology of synthesis products in the Ni-Al-Mn system was studied. The mechanical activation of the Ni + Al + Mn mixture expanded the manganese content limit, at which it is possible to realize the combustion of samples without preheating, from 14 to 49 % (wt.). Preliminary MA made it possible to synthesize a compound containing all three initial metals - the (Ni, Mn)Al phase, which is an ordered solid solution of variable composition based on NiAl. In addition, after MA, the burning rate, elongation of product samples and their porosity increased, and the maximum combustion temperature decreased. An increase in the proportion of manganese in the Ni + Al + Mn mixture led to a decrease in the size of composite particles, elongation of product samples, the maximum combustion temperature, and an increase in the yield of the mixture after MA. The dependence of the combustion rate on the proportion of manganese in the activated mixture Ni + Al + Mn has a maximum.