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The possibility of assessing the impact of the concrete fracture relief and its interphase boundaries on the concrete strength characteristics is considered. Using the fractal theory, the fractal dimension of the concrete fracture relief in 3D space and the phase boundaries in 2D space is determined. The relationship between the above-mentioned fractal dimensions and the breaking load during compression of concrete samples is established. An increase in the indicators of the breaking load by 24% with an increase in the values of the fractal dimension of the fracture relief from 2.202 to 2.268 and the interphase boundaries from 1.699 to 1.782 was recorded. This trend of changes in the values of the breaking load and the fractal dimension of the relief and interfacial boundaries is explained from the standpoint of the mechanics of concrete destruction. A smoother surface of the fracture relief corresponds to higher indicators of its fractal dimension and the strength of concrete. The fractal dimension describes the compactness of filling the space with the object of study, which is higher for a smoother fracture surface. An increase in the fractal dimension of the interfacial boundaries indicates an increase in the energy spent on the work of destruction, and an increase in the strength of concrete accordingly. The obtained fractal models allow us to predict the values of the breaking load of concrete based on the analysis of the surface of the destroyed samples. [ABSTRACT FROM AUTHOR]

The multiparametricity of the production technology of mortar determines its complex structure. The multifractal analysis of a plasticized cement mortar macrostructure was carried out. By analyzing statistical dimensions of the multifractal Renyi spectrum, it was found that the mortar macrostructure has inhomogeneous areas with a predominance of sand or cement stone. Models for predicting bending strength are obtained with a regression analysis of the statistical dimensions values. A relatively high correlation of R2 = 0.75 and R2 = 0.81 among the models under consideration is observed between the fractal dimensions D0 of sand sites and pores. Also, a correlation with strength for the dimension of the structure light sections with sand D100 (R2 = 0.77) and the structure dark sections with a predominance of cement stone D-100 (R2 = 0.66) was established. The sensitivity coefficient between these characteristics was determined to assess the degree of influence of the spectrum of dimensions on bending strength. According to the sensitivity values, the dimensions were ranked to the determining parameter (strength): 1). 0.76 for Do of pores, 2). 0.61 for D100 of sand, 3). 0.60 for D-100 of cement stone, 4). 0.59 for Do of sand, 5). 0.44 for Do of cement stone, 6). 0.41 for D1 of cement stone, 7). 0.40 for D2 of cement stone. Establishing the sensitivity between the dimensions of elements of the mortar structure and the criteria of its quality gives the opportunity to filter out the experiment results, which do not allow us to predict the determining parameter with accuracy acceptable for practical purposes. [ABSTRACT FROM AUTHOR]

The article describes the process of operation of the rotary-scraper sowing device. The results of computer modeling of the process flow chart of the rotary-scraper sowing device, based on a multidimensional deterministic model, built on the input-output principle, are presented. [ABSTRACT FROM AUTHOR]

The article presents a study of the current state of the use of digital technologies in the agro-industrial complex. The development of the agro-industrial complex in the conditions of the digital economy involves the use of innovative, digital, cluster, information and computer technologies, as well as new managerial, economic, organizational methods, with fundamentally new properties, which are aimed at increasing the efficiency of production, management and implementation for all areas of the agro-industrial complex. Based on the analysis of foreign experience, the regulatory framework of the Russian Federation, digital standards, types of digital technologies, the paper considers the types of digital technologies in the agro-industrial complex and the possibility of their use for future development. The methodological basis of the study was the works of domestic scientists-economists on the development of innovations and digital technologies in the agro-industrial complex; general scientific research methods (abstract-logical, economic-statistical, etc.) were used, as well as open analytical materials on the development of digital technologies, the use of artificial intelligence and neural networks in the agro-industrial complex, etc. The article reveals that the range of digital technologies currently being created for the agro-industrial complex is diverse and it is aimed at solving a set of problems: growth of output and the efficiency of the agricultural enterprise, introduction of artificial intelligence; creation of insight based on images; determination of the optimal mixture for agronomic products; monitoring the state of crops; methods of automating irrigation and stimulating farmers, etc. As world best practices show, the use of digital technologies in agriculture makes it possible to achieve economic growth in the industry. However, the main problem of introducing digital technologies in agriculture is the high cost of their implementation. [ABSTRACT FROM AUTHOR]

There exists an entire cluster of robotics tasks, where a system of interconnected mobile platforms appears as the controlled object. When creating a control system for such objects, it is required to take into consideration the influence of all structural elements on their dynamic properties. One of the solutions to this problem lies in introducing a universal mathematical model, which could form the basis for synthesizing a control system. Mathematical model of a system containing interconnected mobile platforms for a mobile robot of a certain class is proposed in this work, which takes into consideration dynamics of all moving structural elements. Solution to the problems set in the work is based on the Gauss’s principle of least constraint. Results obtained are presented in the algorithmic form, and they determine the desired acceleration as a solution to simple linear algebraic equation. Simulation results using the Matlab Simulink software environment are presented. Based on the results of our work, a conclusion was formulated on the suitability of the obtained model for studying properties of the control object. [ABSTRACT FROM AUTHOR]

A review of existing auxiliary control system for prosthesis has been carried out. The concept is proposed for an intelligent prosthesis that will expand the possibilities of application and simplify the use of the prosthesis. An approach to the creation of a human-machine interface system is defined. The required actions are considered for the vision system in automatic and manual capture modes. The sequence of operation of the subsystems of the vision system has been determined. The system of force-torque drive gripper is proposed. The necessity of implementing a decision-making system is shown. The article proposes a variant of the prosthesis design with a reduced number of drives, the possibility of introducing intelligent systems and overload protection. The possibility of constructing the described prosthesis is shown. [ABSTRACT FROM AUTHOR]

A series of experiments were performed by using following geometric primitives and its combinations: sharp and blunt edges, wedge, half-length with "flamholder" or "bump" elements, cylinder, EXOMARS and others. Shock-wave structures are presented in the paper. Numerical calculations are carried out by using the author's codes for the study of aerothermodynamic processes on the model surfaces. [ABSTRACT FROM AUTHOR]

Collisions of asymmetric nuclei (Cu+Au) differ essentially from the case of symmetric nuclei (Cu+Cu, Au+Au) collisions in the geometry of overlap region. This leads to a number of consequences, which provide more absolute and accurate information about fundamental properties of matter under extreme conditions. Nuclear modification factors for π-mesons in Cu+Au interactions at 200 GeV were measured in PHENIX Experiment at RHIC. New experimental data on measurement of flows of different order (v1, v2) for light hadrons in Cu+Au interactions at 200 GeV will be discussed in this paper. [ABSTRACT FROM AUTHOR]

The phase diagram of two-color QCD with a chiral chemical potential is studied on the lattice. The focus is on the confinement/deconfinement phase transition and the breaking/restoration of chiral symmetry. The simulations are carried out with dynamical staggered fermions without rooting. The dependence of the Polyakov loop, the chiral condensate and the corresponding susceptibilities on the chiral chemical potential and the temperature are presented. [ABSTRACT FROM AUTHOR]

We report on the first results for the spectrum of divertor stray light (DSL) and the signal-to-background ratio for D-α light emitted from the far SOL and divertor in JET in the recent ITER-like wall (ILW) campaign. The results support the expectation of a strong impact of DSL upon the H-alpha (and Visible Light) Spectroscopy Diagnostic in ITER. [ABSTRACT FROM AUTHOR]

Plasmonic crystals are metal-dielectric nanostructures that utilize plasmon mediation to enhance material properties. In this talk, I will give an example each for the structures made by either having metal patterns on dielectric or dielectric patterns on metal-dielectric interface or patterned dielectric with metal overlayer. Magneto-plasmonic crystals made by having metal gratings on ferromagnetic thin films are used to demonstrate three orders of magnitude enhancement in transverse magneto-optical Kerr effect (MOKE). For the first time, plasmon mediated enhancement in MOKE in transmission geometry and the use of MOKE measurement as a sensitive tool for detecting surface plasmonpolariton (SPP) resonance has been demonstrated. In structures with dielectric pattern on metal-dielectric interface, possibility of controlling SPP dispersion by choosing appropriate pattern and measurement geometry has been shown. Patterned dielectric with metal overlayer has been used to study the SPP dynamics. [ABSTRACT FROM AUTHOR]

The outstanding performance features of multi-beam klystrons enabled the application of concepts of low power integrated circuits to high power complex microwave devices (CMD). Essential features of CMDs are individual, selective, mutual matching of all sub-components that constitute the CMD, and operational interchangeability of the CMD as a complete system. The CMD concept has enabled a significant decrease in the mass and dimensions of radio-electronic systems and has substantially improved their operational parameters, especially for use in mobile systems. Examples of CMDs are presented. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The work presented here reports the successful construction of photoactive ITO-electrodes based on a layer-by-layer approach. Our strategy, employing donor-linked fullerenes, provides several advantages: Firstly, and far most important, it allows the control over the thickness and composition of the assembled films at a molecular level. Secondly, it guarantees the specific alignment and the orientation of the incorporated donor-acceptor system as a crucial means to facilitate the electron transfer among adjacent layers. Thus, the efficiency of the generated photocurrents is expected to depend on the cooperative interaction of these individual parameters (i.e., film thickness, alignment, orientation, etc.). [ABSTRACT FROM AUTHOR]

A new high precision measurement of the J/Ψ- and Psi′-meson masses has been performed at the VEPP-4M collider using the KEDR detector. The resonant depolarization method has been employed for the absolute calibration of the beam energy. The following mass values have been obtained. MJ/Ψ = 3096.917 ± 0.010 ± 0.007 MeV, MΨ′ = 3686.111 ± 0.025 ± 0.009 MeV. The relative measurement accuracy has reached 4.10-6 for J/Ψ and 7.10-6 for Ψ′, approximately 3 times than in the previous precise experiments. The description of the experiment and the error analysis can be found in hep-ex/0306050, Phys. Lett. B573 (2003) 63-79. [ABSTRACT FROM AUTHOR]