The Radiation-Measuring Complex of the СПРУТ-VI System

The radiation-measuring complex of the -VI system is designed to determine the absorbed dose and values of heavy-nuclei fluxes under a program for investigating isolated failures in microcircuits. The complex is composed of active and passive elements. It is used to measure the total absorbed dose and the radiation doses received by exposed microelectronic elements behind shields of <0.3 and >1 g/cm² (across the range of 10^–4–5 Gy), establish a link between isolated failures and the actual radiation environment, detect nuclear fluxes with a charge of Z > 2 and energies of 30–200 MeV/nucleon, and determine the fluence of heavy charged particles across the range of 1 to 10⁵ cm^–2.     

The Radiation-Monitoring Complex of the СПРУТ-VI System

The radiation-monitoring complex of the -VI system was installed on board the Mir orbital station and used to study the fine structure of the Earth's inner radiation belt in low and near-equatorial latitudes. The complex comprised a system of gas-discharge counters, as well as electron and proton spectrometers. The range of measured energies was 0.1–2.0 MeV for electrons and 0.1–10.0 MeV for protons. The possibility of changing the work program of the complex under spaceflight conditions was provided for.     

Application of the Shack–Hartmann Wavefront Sensor for Monitoring the Parameters of a Supersonic Gas Jet

Results of an experimental study of the density distribution in a small-size (1–2 mm in diameter) supersonic gas jet in vacuum are reported. The measurements are performed by the developed Shack–Hartmann wavefront sensor, which consists of a microlens array with 100 × 100 elements and a video camera with a resolution of 2048 × 2048 pixels. The reliability of measurements in terms of the space and time resolution, as well as in terms of the minimum levels of phase changes induced by the tested object, is analyzed.     

The СПРУТ-VI Instrument Complex for the Mir Orbital Station

The basic elements of the instrument package program for orbital stations are presented. The characteristics of the -VI equipment developed for the Mir orbital station within the framework of this program are described. This equipment allows the simultaneous recording of the characteristics of near-earth space (electron, proton, and nucleus fluxes, magnetic fields, and low-frequency electromagnetic waves) and their effect on the elements of spaceborne equipment and systems. The mass of the equipment is 16 kg; the power consumption is no more than 20 W.     

Principles for Integrating the Smart Grid System with the Enterprise’s Cyberphysical System in Energy Transition 4.0

Russian Engineering Research - The interaction of the smart grid system with cyberphysical systems is investigated. Principles are developed for their integration within the enterprise’s...     

Integral backstepping sliding mode control for underactuated systems: Swing-up and stabilization of the Cart–Pendulum System

In this paper an integral backstepping sliding mode controller is proposed for controlling underactuated systems. A feedback control law is designed based on backstepping algorithm and a sliding surface is introduced in the final stage of the algorithm. The backstepping algorithm makes the controller immune to matched and mismatched uncertainties and the sliding mode control provides robustness. The proposed controller ensures asymptotic stability. The effectiveness of the proposed controller is compared against a coupled sliding mode controller for swing-up and stabilization of the Cart–Pendulum System. Simulation results show that the proposed integral backstepping sliding mode controller is able to reject both matched and mismatched uncertainties with a chattering free control law, while utilizing less control effort than the sliding mode controller.     

Prototype Probe Determining Waveguide–Gum Contact for a Robot Surgical System

Russian Engineering Research - A probe for cutting soft gum tissue combines a force sensor and a diode laser. In such operations, contact between the tip of the optical waveguide and the soft gum...     

Estimation of the Reliability of the Gear–Motor System Using a Markov Model

Journal of Machinery Manufacture and Reliability - In this article, the reliability of a gear–motor system is analyzed on the condition that the failure of the gear leads under certain...     

Micro-to-Nano Indentation and Scratch Hardness in the Ni–Co System: Depth Dependence and Implications for Tribological Behavior

Although size effects in hardness have been extensively reported and analyzed for the static (indentation) case, much less attention has been given to these effects in non-static (scratch) hardness measurements. In the present work, size effects in the indentation and scratch hardness response of the Ni–Co system are evaluated by performing tests at several penetration depths, from the micro to the nanometer range. It is shown that, for all the range of compositions, the hardness response of these materials is strongly affected by the depth of penetration of the indenter: when the depth decreases, both the indentation and scratch hardness increase several times. This result denotes that, when studying the wear behavior of materials, special care must be taken concerning the scale one is dealing with, since the tribo-mechanical response of the material may change significantly from the micrometric to the nanometric contact scale.     

Network Traffic Monitoring on the Basis of Sequential and Associative–Sequential Search Principles

Network traffic monitoring on the basis of sequential and associative–sequential principles of current- information search is assessed in terms of efficiency. Associative–sequential search for information in network traffic permits increased productivity and faster decision making during searches in large information spaces.     

Study of the Wheel–Rail System of Open-Pit Locomotives in Traction Mode

As a result of theoretical and experimental surveys, it is established that the value of the limiting gradient of industrial railways affects the temperature change in the contact area of the wheel–rail system of the locomotives and is characterized by the temperature coefficient of the gradient (k_gradient).     

Influence of the Addition of Vanadium Nitride on the Structure and Specifications of a Diamond–(Fe–Cu–Ni–Sn) Composite System

This article discusses the influence of the addition of vanadium nitride on the mechanical and operational properties of diamond composite material based on metallic bond comprised of iron, copper, nickel, and tin obtained by sintering in a mold at 800°C for 1 h with subsequent hot repressing. It has been established that the addition of vanadium nitride in the amount of 2 wt % to diamond–(51Fe–32Cu–9Ni–8Sn) increases the ultimate compressive strength from 846 to 1640 MPa and bending strength from 680 to 1120 MPa, as well as decreases the wear intensity of the composite material from 0.0069 to 0.0033 g/km. The mechanism of improving the tribological properties has been revealed.     

Wear–Corrosion Resistance of DLC/CoCrMo System for Medical Implants with Different Surface Finishing

The field of medical implants in the human body is a growing area with diverse tribological aspects. This application field has its own specific characteristics, dominated by stringent quality requirements due to the human suffering and sometimes life-threatening consequences of a surface failing to fulfil its required function. Combined wear–corrosion tests could provide more complete information about the implant behaviour in the aggressive body environment than separate wear and corrosion testing. Combined wear–corrosion experiments were performed using a reciprocating ball-on-plate apparatus equipped with an electrochemical cell. Untreated CoCrMo alloy samples as well as diamond-like carbon (DLC) coated samples were used as plate. The DLC coatings were tested with three different surface finishes: as-deposited, polished with diamond and brushed. All DLC coated samples with and without mechanical finishing had lower corrosion activity under wear–corrosion conditions and also smaller wear tracks when compared with the CoCrMo alloy. The current density for the coated alloy was about two orders of magnitude lower on average (10^?5 vs. 10^?3 A cm^?2) and had a final coefficient of friction of only 50% of the uncoated metal (0.15 vs. 0.3). The brushed DLC showed the lowest current density and its behaviour was better than polished DLC and DLC as-deposited up to a potential of +0.93 V.     

Features of application of the extremely-low-frequency–very-low-frequency atmospherics spectrum analyzer for monitoring the earth–ionosphere waveguide state

Features of the operation algorithm of the atmospherics spectrum analyzer and its application for diagnosing the earth–ionosphere waveguide are discussed. It is shown that the selected structure of the spectrum analyzer is expedient. The results are based on the seasonal data obtained at two Polar Geophysical Institute (PGI) observatories, which are located at polar latitudes (“Lovozero” in the Murmansk oblast and “Barentzburg” at the Spitsbergen archipelago).     

Effect of Hydrostatic Pressure on the Optical Parameters of Fiber-Optic Cables for the Calibration System of the НТ-200 Neutrino Telescope

The effect of hydrostatic pressure and its gradient on the optical parameters of fiber-optic cables for the calibration system of the -200 Baikal neutrino telescope was investigated. The mean delay time of the light signal in the fiber-optic cables of the system is shown to be virtually constant at absolute pressures varying from 0 to 150 atm; incidentally, the average signal amplitude decreases by 5%. When the pressure difference changes from 0 to 7 atm, the average signal delay time increases by 0.5 ns, and the average signal amplitude decreases by 17%.     

A РК-АГ-02 α–γ-Radiometer–Spectrometer for Proximate Monitoring of 241Am and Other Transuranium Radionuclides

A --02 –-radiometer–spectrometer is made up of a refined detector on the basis of a GSO scintillator and a CASSIOPEIA A-11A laptop personal computer. This instrument can measure ²⁴¹Am activity in samples, without their concentration and radiochemical treatment, against a high (10^–3) background level due to the accompanying radionuclides (¹³⁴Cs, ¹³⁷Cs, ¹⁵⁴Eu, ¹⁵⁵Eu, etc). The maximum detectable activities for field and laboratory modifications of the instrument are 0.7 and 0.25 Bq per sample, respectively (for a measurement time of 8 h). In addition, this instrument can measure an -particle flux density from 0.15 s^–1cm^–2and perform the spectrometry of low-energy -rays over a 20- to 200-keV range (analog spectrometry by three differential channels and multichannel spectrometry with the use of an external analyzer).     

Development of a 635 nm-Laser Diode Spectrometer for Continuous Monitoring of Amino Nitrogen in the Beet Sugar Industry

Abstract

The quality of sugar beet is affected by harmful nitrogen compounds. Although nitrogen is one of the essential elements for plants, introduction of excess nitrogen as fertilizer to the soil increases the nitrogen containing compounds in beet which deteriorates the quality of sugar production. Hence, the concentration of soluble nitrogen in beets was monitored as a routine process in the sugar industry. In this work, a low cost, but very long life time laser diode spectrometer, was developed for continuous monitoring of amino nitrogen compounds in sugar beets. A laser diode source emits monochromatic light at 635 nm which is the maximum of absorption spectrum of Cu(II)-glutamine complex. A standard solution of Cu(II) ion and glutamine was prepared at pH = 6.0 to calibrate the laser diode spectrometer. The formation of Cu(II)-glutamine complex was examined at pH = 5.0, 6.0, and 7.0 by a continuous variations method and we found a monovalent complex, Cu(II)(glutamine) at pH = 6.0, and a divalent complex, Cu(II)(glutamine)₂ at pH = 7.0. A continuous mixing system with a peristaltic pump and tubing was set for monitoring of harmful nitrogen in beets, besides sugar determination with a polarimeter and Na and K measurement with a flame photometer, synchronously. The calibration of the laser diode spectrometer yielded a linear correlation coefficient of R² = 0.999. A negative correlation between sugar digestion and amino nitrogen content of sugar beets was found, with a correlation coefficient of R² = 0.807.     

Application of Computational Fluid Dynamics and Fluid–Structure Interaction Method to the Lubrication Study of a Rotor–Bearing System

Computational methods were used to analyse the elasto-hydrodynamic lubrication of a complex rotor–bearing system. The methodology employed computational fluid dynamics (CFD), based on the Navier–Stokes equation and a fluid–structure interaction (FSI) technique. A series of models representing the system were built using the CFD–FSI methodology to investigate the interaction between the lubrication of the fluid film, and elastic dynamics of the rotor and journal bearing. All models followed an assumption of isothermal behaviour. The FSI methodology was implemented by setting nodal forces and displacements to equilibrium at the fluid–structure interface, therefore allowing the lubrication of the fluid and the elastic deformation of structures to be solved simultaneously. This is significantly different to the more common techniques—such as the Reynolds equation method—that use an iterative solution to balance the imposed load and the force resulting from the pressure of the fluid film to within a set tolerance. Predictions using the CFD–FSI method were compared with the results of an experimental study and the predictions from an ‘in-house’ lubrication code based on the Reynolds equation. The dynamic response of the system was investigated with both rigid and flexible bodies for a range of different bearing materials and dynamic unbalanced loads. Cavitation within the fluid film was represented in the CFD–FSI method using a simplified phase change boundary condition. This allowed the transition between the liquid and vapour phases to be derived from the lubricant’s properties as a function of pressure. The combination of CFD and FSI was shown to be a useful tool for the investigation of the hydrodynamic and elasto-hydrodynamic lubrications of a rotor–bearing system. The elastic deformation of the bearing and dynamic unbalanced loading of the rotor had significant effects on the position of its locus.