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  • Formation exact self-similar solution of the problem of hydrodynamic thrust bearing calculation, which has a higher load capacity and damping properties, working on a two-layer lubrication in the transient regime of friction

    In this paper is presented a method of forming an exact self-similar solution of the problem of calculating the hydrodynamic thrust bearing with an adapted profile support surface and emfiruyuschimi properties in the transient regime of friction. Prepared and conducted evaluation of the main working characteristics: dimensionless load carrying capacity, dimensionless friction force and dimensionless costs. The optimal parameters for the main performance are gotten.

    Keywords: thrust bearing, two-layer lubrication, porous layer, the nonstationary problem

  • Being self-compacting concrete of the lowered density with application of a volcanic tufa

    Advantages of being self-сщьзсештп concrete of the lowered density (LSUB) before heavy and light concrete are shined, characteristics of components ЛСУБа and influence of their quantitative contents are provided in a mix on properties of the fresh and hardened concrete. The optimum mode of warmly moist processing is offered.

    Keywords: Self-compacting concrete, the supersoftener, knitting, filler, a volcanic tufa.

  • Solution of one-criterion optimization problem of crew actions scheduling on Russian segment of International space station

    The flight scheduling process is briefly described in the article. It is one of the most important stages of space flight control task solution. Three stages of flight scheduling are given: strategic, tactical and executive. The result of each scheduling phase is presented by special plan type: on-orbit operation summary, weekly lookahead plan, short-term plan. The difference of these plan types is in planning interval and data processing depth. The mathematical modeling of all required data and restrictions is made. A crew downtime minimization is the selected optimization criterion. Modified genetic algorithm for decision of assigned task is designed. The future tasks regarding crew activities scheduling process optimization are defined  

    Keywords: scheduling, flight operation, crew activities, optimization, mathematical modeling, genetic algorithm

  • Silent interval detection in speech signals

    A voice activity detector (VAD) is a device, which analyses a speech signal and generates the signal corresponding to the period containing only noise. In the present work is offered VAD, which increases the probability of correct detection the presence or absence of human speech.
    The correct detection begins with SNR 7-10 dB. The quality of  derived speech signal remains the same.  

    Keywords: voice activity detection, voice activity detector, VAD, silent interval detection, speech, speech signals

  • Issues of case-based reasoning, detalization, integration and similarity assessment of cases

    Case is an event that took place in the past and can be an example for similar steps in present. Case-based reasoning (CBR) is a methodology of finding a decision based on previous experience. The main difficulties in CBR are recognition of present situation of decision-making and finding similar case in the past. Making a decision in the field of purchasing drugs is a quite difficult and many-valued task with a plenty of various parameters, which however might be solved with the help of CBR. CBR is an important and perspective area of artificial intelligence (AI) decision support systems. Constantly growing research amount has already led to breakthroughs in theoretical part of AI and in AI-based applications. The general case model and formula for determining cases similarity is suggested in this work. Application of the formula will help determine similarity of cases and make the better decision.

    Keywords: case, case-based reasoning, case description, decision support system, case-based decision making

  • Key component of a personnel management system

    Selection of shots – one of key components of a personnel management system. Trial and error methods of the personnel share on active and passive, and sources of attraction of shots – external and internal. Active trial and error methods use, in the majority when on a labor market demand exceeds the offer. Passive trial and error methods use when the offer on a labor market exceeds demand. Most widespread of passive methods can call placement of announcements in which the name of open vacancy, requirements to competitors is indicated to a position, work terms of payment. To external sources of attraction of the shots, applied most actively, rank: the announcement on television, in newspapers, on radio, on the Internet; visit by employees of the company of educational institutions; appeal to the centers of employment of the population and staff recruitment agency. Search plus in the company is that fact that when filling vacancy to this position the person familiar with orders of the organization, with its personnel and rate of work that is pledge of successful work gets. The worker adapts for a new position easier. Advantage of an internal set is an increase of motivation at employees to better performance of duties. One more plus – comparative low cost in comparison with external. Qualitatively new approach to selection of the shots arriving for work in the prestigious companies is offered. The experts possessing desire and ability of strategic planning of development of business and as persons are necessary for the advanced company.  

    Keywords: personnel, selection, selection, integrated approach, strategic thinking, profit, collective

  • Automatic air temperature measurement system airflow

    A scheme of the experimental setup of the jet air temperature measurement. Experimental results confirm the dependence of the frequency stabilnost pneumatic signal from the flow temperature with a large number of measurements.

    Keywords: pneumatics, temperature, piezo, airflow, sensor stuyny

  • The load distribution in the adaptive friction clutches of the second generation (Part 1)

    With the increase in the coefficient of friction is a growth of the torque transmitted by the lead pair of friction of the main friction, reducing torque is transmitted by the slave pairs of friction friction core group and a couple of extra friction of the friction. Load transfer in the adaptive friction clutches reduces spacer force and accelerate the growth of the torque transmitted by the friction pair of the main driving frictional group.

    Keywords: the coefficient gain, a separate positive connection, the coefficient of friction, clutch, friction pair

  • The load distribution in the adaptive friction clutches of the second generation (Part 2)

    The coefficient of friction, whereby the total nominal load adaptive clutch transmitted only the leading pair of friction friction basic group is less than the maximum value, which may take the coefficient of friction in actual operation of the coupling. Appearance and an increase in the strength of the spacer when the external load and increasing at an elevated value of the friction coefficient begins at a certain minimum value of the external load, which depends on the total number of pairs of friction of the friction core and the gain. The dependences of the distributions of the torque between the lead pair of friction friction main group and driven friction pairs of basic friction and friction pair of extra friction.  

    Keywords: the coefficient gain, a separate positive connection, the coefficient of friction, clutch, friction pair

  • Methods for modeling the stress-strain state to determine residual life of reinforced concrete console spillway under various boundary conditions

    This article discusses methods of modeling the stress- strain state needed to evaluate the different boundary conditions of the technical state of reinforced concrete cantilever operated long spillway. Most long- operated hydraulic structures in Russia is unsatisfactory condition requiring modernization and refurbishment. After a long period of operation waterworks continue to work without a planned repairs necessary to make the technical reconstruction of buildings on the basis of innovation , as well as previously proven technology of repair. Console spillway - open conjugating hydraulic structure where the water first moves over the construction , and then - the water flow freely reset to unfortified ground. Such structures the most economical , since the same difference befov their reinforced concrete part of a much smaller, and no part of the stilling strengthened and basically they are arranged on the rocky soil . When soils are weak, then you must make the console damper on long distance or strengthen easily eroded soil in the fall of the water flow. In the most dangerous cases falling from the absorber fed to a stilling well, for energy dissipation , from which he subsequently moved away from the building. Assessed the degree of accident risk of reinforced concrete elements console spillway . In the experiment sought to identify the residual resource , namely the reliability of the technical state of facilities for the period of operation, more than 60 years , in different types of defects and damages , as well as the estimated residual life . A complex system using a database Microsoft Access.

    Keywords: waterworks, console spillway, the stress-strain state, numerical modeling, technical condition, residual life.

  • Algorithm for solving the problem of optimal allocation of energy resources of the region

    To solve the problem of choosing an algorithm of optimal allocation of resources to development of the energy producing industry, initially held the formalization of this task and the required payment ratio. The relationship led to the conclusion of one of the most effective methods for finding optimal solutions-dynamic programming method  

    Keywords: algorithm, еnergootrasl, distribution, development, function, script charts, dynamic programming

  • The method of functionally integrated laser-modulators design

    The proposed method of designing hardware components optical switching systems simplifies prototyping and development of systems of optical switching and multi-core VLSI. This method allows to automatically set parameters of the optical system at the design stage, depending on the requirements. This method may be cost-effective at the stage of technical specifications of the project, as will reduce the time required for its coordination between the customer and the design engineer.
    At the heart of developing a method of designing systems, optical switching elements is a comprehensive analysis of the equations and functions describing the electrical and optical properties of laser heterostructures, as well as electro-optic modulators and Fabry-Perrot resonators. Fundamental static and dynamic characteristics of semiconductor diode lasers can be calculated by using a set of kinetic equations describing the interaction of electrons, holes and photons in the active layer of the laser structure. At various stages of this method is processing, evaluation and calculation of the main characteristics of the elements of integrated optical switching systems.  

    Keywords: optical switching, integrated injection laser, quantum-scale heterostructure, amplitude modulation, terahertz range

  • The Electrically Active Impurities Inhomogeneous Distribution Influence on The Charge Carriers Transfer in Metal-semiconductor Contacts with Schottky Barrier

    The mathematical model and the simulation of metal-semiconductor contacts with Schottky barrier volt-ampere characteristics taking into account electrically active impurities inhomogeneous distribution in semiconductor are proposed in this work. The developed mathematical model takes into account quantum mechanical effects during the charge carriers transfer in metal-semiconductor junctions with Schottky barrier and allows forecasting their volt-ampere characteristics. The simulation results meet the experimental data from famous literary sources. The developed mathematical model can be used in computer aided design of integrated circuits elements.

    Keywords: Schottky diode, potential, Poisson equation, volt-ampere characteristic

  • SYSTEM ENGINEERING OF OPTIMAL DESIGN OF ELEMENTS OF STRUCTURAL UNITS

    Possibilities of using mathematical programming methods for obtaining optimal solutions of structural units were shown herein. Method of personal optimization based on monotonicity property of the used relations was applied as optimization algorithm. Advisability of using mathematical simulation methods when providing complex safety of construction facilities and reduction of breakdown occurrence is emphasized.

    Keywords: optimal design, mathematical simulation, complex safety, personal optimization, plate structures, risk.

  • Computer-aided Diagnostic System of Semiconductor Structures

    Computer-aided diagnostic system of semiconductor structures for the tested structures volt-ampere and voltage-capacitance characteristics measuring at different temperatures in wide ranging bias voltage was made in this work. Computer-aided diagnostic system of semiconductor structures allows to define parameters of deep-lying levels, profiles of alloying impurities distribution, charge carriers life span, surface states energy spectrum density with high reliability and efficiency and can be used for processing and optimization of technological modes for solid-state electronics structures generation.

    Keywords: diagnostics, dynamic spectroscopy of deep-lying levels , spectrum, deep-lying levels, surface states, profile of impurity distribution