Attitude Diagrams for the Description of the Attitude Drift of Torquefree Asymmetric Gyros

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Analysis of the process of immersion of kernels in liquids with different specific mass

In a grain pile there is material other than grain including poisonous ergot sclerotia. Grain and sclerotia of ergot by linear dimensions and speed of soaring have similar characteristics. Complete separation of grain from ergot by these properties in a single process is impossible. Cleaning seeds from ergot sclerotia with the specific mass less than the specific mass of grain is possible in a salt solution. To mechanize the separation of ergot sclerotia from rye seeds by the wet method, there is an urgent need in the development of an appropriate device. Under study was an immersion in water (ρzh = 1.0∙103 kg/m3 ) and aqueous solutions of sodium chloride (NaCl) with a specific mass ρzh = 1.09∙103 and 1.15∙103 kg/m3 of individual rye grains with their specific mass ρz = 1.2...1.5∙103 kg/m3 , length lz = 5.0...10.0 10-3 m, width в = 1.4...3.6∙10-3 m and thickness δ = 1.2...3.5∙10-3 m. Theoretical studies were carried out on the basis of mathematical modeling methods using the laws of hydrodynamics, which were confirmed by experimental studies with winter rye grains of the Falenskaya 4 variety with a specific mass ρz = 1.1...1.3 103 kg/m3 , length lz = 5.0...8.0∙10-3 m, width в = 1.4...3.6∙10-3 m and thickness δ = 1.2...3.5∙10-3 m. It has been established that the calculated values of the immersion velocity of cylindrical kernels and spheroidal kernels in comparison with the experimental values in water (ρzh = 1.0∙103 kg/m3 ) is not more than 2%, and in aqueous solutions of sodium chloride (NaCl) the specific mass ρzh = 1.09∙103 and 1.15∙103 kg/m3 – 7 and 10%, respectively. This approach to determining the speed of immersion of grain in liquid can be used in the development of the machine for cleaning grain according to specific mass using wet method to substantiate its structural and technological parameters

Performance of Technical Trading Rules in the US and Swedish Stock Markets

Master thesis Business Administration- University of Agder, 2015In this thesis I am testing the performance of two of the most popular market-timing strategies, the simple-moving average and time-series momentum, compared to the performance of the passive buy-and-hold strategy using in-sample testing. The strategies are implemented on two sets of data, one being the S&P500 for the period 1926 to 2013, and the second the Swedish stock market for the period 1919 to 2006. I replicate the results of previous studies on the S&P500, and also contribute to the ongoing research by extending the testing of the performance of the market-timing strategies to the Swedish stock market. The results of the in-sample test show that the market-timing strategies have better performance than the passive buy-and-hold strategy. However there are too many uncertain factors to conclude that the market-timing strategies are superior to the passive buy-and-hold strategy without conducting further extensive research

Development of Technology for Processing Oil Sludge with Application of Super High Frequency Electromagnetic Fields

This article considers the problem of processing and disposing of oil sludge of various origins. Large oil companies are concerned about the problem of incomplete processing of oil sludge. The most hazardous from an environmental point of view include oil sludge formed at all stages of oil production, transportation and refining. In recent years, oil-producing enterprises have introduced various technological solutions aimed at waste management into production, but there is no single method for processing oil sludge for the purpose of neutralization and disposal. All known oil sludge processing technologies by processing methods can be divided into the following groups: thermal - burning in open barns, furnaces of various types, obtaining bitumen residues; physical - burial in special cemeteries, separation in a centrifugal field, vacuum filtration and filtration under pressure; physical and chemical - the use of specially selected reagents that change the physical and chemical properties, followed by processing on special equipment; and biological - microbiological decomposition in the soil directly in storage, biothermal decomposition. Each of them, while having certain advantages, also has its drawbacks. For over 50 years, microwave heating technology has been used in industry. To present the advantages of this method, one needs to turn to the theory of microwave heating. Keywords: oil sludge, oil waste, influence of electromagnetic fields, water-in-oil emulsion

Viscosity and electric conductivity of melt system of CaO – Al2O3 - B2O3

It was studied the viscosity and electric conductivity of the melt system CaO - Al2O3 - B2O3. On the base of experimental data it was created the mathematical model of studied features dependence on chemical structure of melt and temperature. There were created the computer programs which allow to calculate the temperature range at 1 823 – 1 973 K. There were constructed the triaxial diagrams based on models. It was found the reduction of viscosity and extension of electric conductivity of melt CaO - Al2O3 by adding B2O3

Improvement of Efficiency of Air Cooling Devices By Creation of Independent Modules with Evolvent Profile Composition of Finned Tubes

An analysis of the composition of the heat-exchange equipment at the petrochemical plants reveals that nominally more than 30% (and by weight about 50% of the total equipment) is heat-exchange equipment, including air-cooled units requiring replacement and reconstruction as a result of the end of their service life or corrosion erosion wear. Therefore, work aimed at improving the effectiveness of ABO is relevant. The existing problem of reducing the efficiency of air cooling in hot calm weather is compounded by the need for short-term humidification using a humidifier mounted directly behind the fan wheel when the air enters the diffuser. This dramatically increases the processes of corrosion and the formation of deposits on the surface of finned tubes (scale, fluff and dust). We have carried out a set of computational and experimental studies to evaluate the thermal efficiency of small-sized ABOs of various designs using a universal experimental industrial bench. The results of studies have established that vertical-cylindrical ABO designs are more energy-efficient and less metal-intensive compared to typical horizontal ones and allow for the influx of cold atmospheric air to the ABO inlet during the hot season. Keywords: air cooler; heat transfer coefficient; thermal efficiency; design of a vertical cylindrical air-cooling apparatus; involute profile layou

Erstarren eines antriebslosen dissipativen Modellkreisels

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Strukturelle Resonanzen und die Lagedrift drehmomentfreier Kreiselsatelliten

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Национально-региональные энциклопедии России: основа и особенности развития

The article presents the main development stages of the national regional encyclopedia science of Russia in the context of European and world encyclopedias formation. The main specific problems of encyclopedic activity and its role and place in modern science and practice in Russia at the present stage are discussed in the paper.В статье представлены основные этапы и истоки развития национально-регионального энциклопедического дела России и Башкортостана в контексте становления европейской и мировой энциклопедистики. Определены основные проблемы, характерные для энциклопедического дела в России на современном этапе, рассматриваются его роль и место в современной науке и практике