In the development of cloud providers, not only the types of services they provide play a significant role, but also fault tolerance to service failures. It is important for a cloud service provider to prepare and configure the server and service for fault-tolerant operation so that the customer works with a high degree of readiness and reliability in the system allocated to him. To prepare such a server, it is very important to think carefully about the architecture of the virtual machine, on which all the necessary means of data exchange and integration for the operation of the service will be installed, and protection against network threats that can disrupt the server's performance will be configured. The purpose of the work is to create a virtual machine architecture protected from network threats, which provides customers with access to the iTOP CMDB system. Despite the fact that there can be any number of customers, the iTOP CMDB system should be provided to each customer with its own version, which he can administer. The user can log in using an Internet browser by entering the name of his organization as a domain. The authors present a demonstration of the iTOP CMDB system, which is located on a virtual machine protected from network threats.
Keywords: virtual machine, architecture, firewall, iTOP CMDB system, server, network threat, network attack, IP address, firewall, request
The article provides a solution to the problem of optimizing air ducts with a rectangular cross-section for ventilation and air conditioning systems. Based on the use of the methodology for optimizing air ducts according to the above costs, the optimal proportions of the sides of the rectangular cross-section of the duct are determined, depending on the amount of material costs for the duct device and the cost indicators of its operation. The obtained optimal aspect ratios of the cross sections of the ducts are universal and do not depend on the location of the duct relative to the system fan. These conditions allow, at the design stage of the ventilation system, to assess the degree of optimality of the decisions made on the choice of the dimensions of the cross-sections of the ducts and, if necessary, to make appropriate changes to the design solutions of the ventilation system. The obtained optimality conditions allow them to be included in the calculation programs of the air.
Keywords: fan, air heater, ventilation system, heating and ventilation system, energy, power, energy efficiency, energy conversion, mechanical power flow, thermodynamic system
The article analyzes network traffic in WINDOWS operating systems, as well as a description of its tools to identify a certain redundancy of network activity. The authors also conduct a comparative analysis of the most common software products that perform the functions of monitoring network traffic.
Keywords: operating system, detection systems, network protocol, network traffic analysis, networks, sniffer, traffic, network activity
The article presents an overview of the current situation in the field of energy saving of the Russian Federation. Topical issues of energy efficiency control of buildings and structures as an energy saving tool are considered. The proposed approach allows, while maintaining the General ideology of SP 50.13330.2012 "Thermal protection of buildings", to modify the scale of energy efficiency of buildings and structures, to make it comparable with similar scales adopted in leading European countries. A similar approach to solving this problem is implemented in order to move from the percentage deviation of the level of heat loss (from some basic value) directly to the specific level of these heat losses per unit area. The formula allowing to calculate both normalized and actual value of heat energy consumption for heating and ventilation of buildings is deduced. In the future, the above-mentioned formula is transformed into a formula that takes into account engineering solutions, both with a direct-flow ventilation system and with the use of a recuperative heat exchanger.
Keywords: heat supply, housing and communal services, energy efficiency, energy saving, energy efficiency scale, specific energy consumption, regulatory framework
The strength, deformability and width of the opening of normal cracks of prototypes 220, section 12.5x25 (h) cm, reinforced with composite canvases and laminates of different cross-sectional areas, made on the basis of glass and carbon plastics, are compared. The samples had working reinforcement, represented by 2Ø14А600, transverse - with double-section clamps Ø5В500, installed with a pitch of 100 mm. Samples were loaded with two concentrated forces applied in thirds of the span. With composite reinforcement, the appearance of the external composite reinforcement was varied, as well as the presence or absence of U-shaped anchoring clamps glued to the supporting sections of the beams. It has been established that the greatest reinforcing effect is provided by composite materials based on carbon fibers, in which the modulus of elasticity is comparable to the modulus of elasticity of steel.
Keywords: concrete, reinforced concrete, bending element, composite, fiberglass, carbon fiber, strength, deformability
The structural properties of cobalt catalysts and their active component are studied. The influence of metal oxides on the specific surface area, pore volume and size, the average crystallite size and the active surface area of the catalyst Co-Al2O3/SiO2 was studied.
Keywords: Fischer-Tropsch synthesis, synthetic hydrocarbons, catalyst, cobalt, promoter, carrier, specific surface, porous structure, catalytic activity, degree of reduction, active surface area
The physical and chemical properties of cobalt catalysts promoted by manganese oxides for the synthesis of hydrocarbons by the Fischer-Tropsch method are studied. The influence of polymorphic modifications of the alumina carrier on the specific surface area, pore volume, degree of reduction, size of cobalt crystallites,catalytic activity, dispersion degree of catalyst reduction is considered.
Keywords: Synthesis of Fischer-Tropsch, synthetic hydrocarbons, the cobalt catalyst, promoter MnO2, the carrier of Al2O3, specific surface area, the degree of recovery of the catalytic activity, dispersion, and the crystallites of cobalt
The parameters of the porous structure and the active surface of cobalt catalysts for Fischer-Tropsch synthesis (SFT) prepared by the impregnation method have been studied. Characteristics of composition and porous structure were studied using elemental analysis and the Brunauer-Emmett-Taylor method (BET). The effect of the addition of oxide promoters on the specific surface area, pore volume and pore size of the Co / SiO2 catalyst has been studied.
Keywords: Fischer-Tropsch synthesis, heterogeneous catalyst, promoter, carrier, specific surface area, porous structure, selectivity, activity, dipping method
The parameters of the porous structure and the outer surface of cobalt catalysts for the synthesis of Fischer-Tropsch, promoted by magnesium, prepared by the impregnation method according to moisture capacity, were studied. The effect of polymorphic modification (γ, θ, α) of the carrier on the physicochemical properties of the catalyst Co-Mg / Al2O3 was studied.
Keywords: Fischer-Tropsch synthesis, polymorphic modifications of Al2O3, synthetic motor fuel, catalyst, carrier, elemental analysis, BET method, specific surface, porous structure
Three batches of Co-MxOy / SiO2 catalysts were prepared with different methods of introducing an oxide additive. Physicochemical studies of catalysts by elemental analysis and Brunauer-Emmett-Taylor (BET) methods have been carried out. The effect of additives of oxide promoters and the method of their introduction on the specific surface, volume and pore sizes for Fischer-Tropsch synthesis catalysts were studied.
Keywords: Fischer-Tropsch synthesis, carbon-containing resources, catalyst, active component, silicate carrier, Al2O3 and ZrO2 promoters, elemental analysis, BET method, surface area, volume and pore size
Using the methods of thermo-programmed reduction (TPV) and thermo-programmed hydrogen desorption (TPD H2), physico-chemical studies of Co-MxOy / SiO2 catalysts obtained by various methods of introducing a promoter additive were carried out. The effect of the introduction method and the nature of the promoting oxide additive on the properties of the active component of the Fischer-Tropsch synthesis catalysts was studied.
Keywords: Fischer-Tropsch synthesis, catalyst, active component, silicate carrier, Al2O3 and ZrO2 promoters, TPV and TPD H2 methods, crystallite size, degree of reduction, dispersity
The physical and chemical properties of cobalt catalysts for Fischer-Tropsch synthesis have been studied. The effect of copper and iron oxides on the specific surface, pore volume and dimensions, and the degree of reduction of metallic cobalt on the surface of the Co-Al2O3 / SiO2 catalyst have been studied.
Keywords: Fischer-Tropsch synthesis, synthetic hydrocarbons, catalyst, cobalt, promoter, carrier, specific surface, porous structure, catalytic activity, reduction degree
The dispersion parameters of the active component of cobalt catalysts promoted by nickel for Fischer-Tropsch synthesis by the temperature-programmed hydrogen desorption method (TPD H2) were studied. The influence of the polymorph (γ, θ, α) of the support on the physicochemical properties of the Co-Ni / Al2O3 catalyst was studied.
Keywords: Fischer-Tropsch synthesis, biomass, catalyst, support, Ni promoter, polymorphic Al2O3 modifications, TPD H2 method, active surface, dispersity, cobalt crystallites
The article proposes a technique for constructing a model for optimizing the taxation of profits for its implementation in the practice of organizations - large taxpayers in both the Rostov region and the Russian Federation as a whole. Methods for calculating the coefficients for assessing the efficiency of the mechanism for optimizing the taxation of profits of organizations - large taxpayers - are proposed.
Keywords: financial stability, tax burden, tax benefit, optimization, taxation, taxpayer, profit
The article deals with the issues related to the study of aerodynamic and energy characteristics of the two layout solutions of mechanical ventilation and air conditioning systems - with the placement of the fan before and after the heater. Based on the use of graphoanalytic method of studying the parameters of the fan in the ventilation network, the dependences determining the aerodynamic and energy characteristics of the systems in three characteristic modes of their operation - at ambient temperatures equal to the design, the average temperature of the heating period and +8 ° C are obtained. The obtained dependences indicate that the installation of the air heater after the fan allows to increase the level of energy efficiency of the system in comparison with the placement of the air heater in front of the fan in the cold period of the year under the thermally unsteady operation of the supply ventilation system.
Keywords: fan, air heater, ventilation system, air conditioning system, power, energy saving, energy efficiency, non-stationary mode, the cold period of the year, the method of imposing characteristics