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Physics, mathematics, and technology

Mathematics and computer science

About geometrical objects fields of the -framed hypersurface of the projective space

Abstract

The second-order curvature object contains the curvature object of the fundamental-group connection defined in the principal bundle; the curvature object of an affine connection over a manifold; second-order components. Differential comparisons for the components of the object of curvature of the second- order fundamental-group connection are made. These comparisons show that the curvature object forms a geometric object only in combination with components of the second-order connectivity object. In the general case, the object of curvature of the fundamental group connection of the second order does not form a tensor.

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The curvature object of the fundamental-group connection of the second-order

Abstract

The special class of (-framed) hypersurfaces of the projective space Pn — is defined, and its existence theorem is proved. In the differential 3rd order neighbourhood: (a) Norden–Timofeyev's normalization of the hypersurface; (b) two Norden's normalizations of the tangent -subbundle; (c) in each L-plane three one-parameter sheaves of its Norden's 2nd kind normals–are constructed internally invariantly.

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The hierarchy of the subgroups of the linear group at isolation of one index value

Abstract

Non effective, factor-effective and special-effective projective spaces are considered. In an non effective projective space the linear group is acting. When one index value is isolated in the Cartan structure equations of a linear group, the hierarchy of its seven subgroups is constructed.

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Theoretical and experimental physics

Modeling of the cathode thermal conditions

Abstract

This article provides results of the cathode of stationary plasma engine thermal vacuum test with various operating modes simulated, a thermal calculation and the cathode thermal mathematical model verification. Based on the calculations, the cathode thermal model and operating performances were assessed, the most efficient required cathode life time characteristics were selected, which are related to the cathode heater power and operating time with provision of emitter optimal temperature in the automatic mode and welded joints leak-tightness. It was determined that the minimum heater power for cathode start-up is 60 W, the time to prepare for a start-up is 140 sec. To improve the cathode stable operation it is recommended to replace the tail piece and getter cover material for Molybdenum М99.95-МП.

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Role visual models of the functional hybrid intelligent system with the heterogeneous visual field

Abstract

The paper presents role visual models of a homogeneous and heterogeneous problem, an autonomous and integrated method, an element that is an expert of collective intelligence, a functional hybrid intelligent system that is artificial collective intelligence. The proposed models are the basis for visual modeling of hybrid intelligent systems that dynamically synthesize an integrated model and method over heterogeneous model and visual fields and simulate the cooperation, relativity and complementarity of collective intelligence for finding solutions on verbal-symbolic and visual-shaped languages.

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A receiving-transmitting antenna system of a mobile object

Abstract

The article is devoted to the development of the structure and functional nodes of a short-wave range of a transmit-receive antenna with a controlled radiation pattern. The ways of solving the problem of electromagnetic compatibility of radio electronic means located in a limited volume on the surface of the mobile object and integrating the antenna into the flat surfaces of the hull are determined.

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To the question of creating a stationary plasma engine of increased power

Abstract

The new concept of powerful electric thrusters for spacecraft are aimed at creation of power plants for transportation of satellites with a large mass support manned space programs, space transportation and missions to study outer space. As the main engine for such systems, the choice of stationary plasma thruster (SPT) high power. This article presents an overview of SPT big power and issues when they are created.

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Visual modeling of group processes in decision-making by a small team of experts

Abstract

The features of the problem solving process by a small team of experts and their visualization are considered. Relevant application of the proposed visualization tools in virtual heterogeneous teams at different stages of the collective problem solving process will ensure their stability in the zone of discomfort when the probability of the team's disintegration is high. Visualization of the complex problem solving process in virtual heterogeneous teams will increase the degree of confidence in the results of their work due to a visual representation of the reasons that led to the decision.

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Mechanics

Dynamics of a cargo lift system

Abstract

A device for lifting of a cargo is modeled by a mechanical system with three degrees of freedom. With the increase in the weight of the load is reduced the steady-state rotation speed of the drum, the settling time varies slightly. The calculation of the oscillation frequency of the cable relative to the vertical. It is established that change of the angular velocity deviations correspond to oscillations of mathematical pendulum with variable length strings. Reducing the axial moment of inertia of the drum, ceteris paribus, affects neither the steady-state angular velocity of rotation of the drum or the value of the steady-state elongation of the cable, but changes during the transition process. However, affects the frequency and magnitude of deviations of the cable from the vertical. The increase in the initial angle only leads to the growth of the largest deviations of the cable from the vertical; increase the aerodynamic drag of the cargo to its reduction.

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