Volga State University of Water Transport

About: Volga State University of Water Transport is a education organization based out in Nizhny Novgorod, Russia. It is known for research contribution in the topics: Attractor & Deformation (engineering). The organization has 71 authors who have published 75 publications receiving 224 citations.

Applied Problems of Magnetism

Abstract: The saturation magnetization of single-crystalline garnet ferrite films of different compositions is calculated on the basis of the familiar relations of the Neel model on the sublattice structure of ferrimagnetic compounds. Other parameters of the films are calculated using the theory of strip domains and the stability theory of cylindrical magnetic domains. The presented material is educational and intended for use in practical exercises in the study of magnetism. The problem is given to students of specialties 22.03.01, Materials Science and Materials Technology (when studying the discipline of Physics of Magnetic Materials); 03.03.02, Physics (when studying the disciplines of General Physics, in the section on Electricity and Magnetism and the disciplines of the Magnetic Properties of Matter); and to students of specialty 13.03.02, Electric Power Engineering and Electrical Engineering (when studying the discipline of Magnetic Measurements) at Astrakhan State University.

Variable diesel-generator power plant based on double-fed machine

Abstract: The article considers the problem of improving power efficiency of the diesel generator power plants as one of the priority objectives for development of low power generation in Russia. Improving energy efficiency for autonomous facilities is directly related to the optimization of hydrocarbon fuel consumption by marine diesel engines. It is possible to optimize the fuel consumption of internal combustion engines by creating variable-speed diesel generators (VSDG), which are diesel-generator units with semiconductor converters, i.e. systems with valved generators. Optimization of specific fuel consumption by VSDG is provided by the forced regulation of the rotational speed of the shaft of the internal combustion engine in accordance with its multi-parameter characteristic in the shared load conditions of the power plant. The synchronous electric machine is used as a generator as part of a ship power station. Its use in the classic constant-speed diesel generators is more preferable than an asynchronous electric machine. In the development of VSDG - valved power plant - the use of an electric machine with a phase rotor as a generator is technically justified, because the installed capacity of the frequency converter in the rotor circuit of an asynchronous generator with a phase rotor is determined by the sliding power and, with a limited range of speed control, SDGV significantly reduces the installed capacity of the electrical equipment. Such power topology of a ship’s power plant is called VSDG based on a dual-power machine. There has been proposed to consider a variant of a ship power plant based on VSDG with a dual-power machine. Its functional diagram and mathematical model are developed. A structural diagram is presented and dynamic modes of the amplitude and frequency of the generated voltage are modeled during electrical load switching.

Stationary object servicing dispatching problems in a one-dimensional processor working zone

Abstract: We consider a system where servicing of a collection of stationary objects distributed inside a one-dimensional zone is done by a moving processor. One-time servicing of each object must be performed during two runs of the processor, direct and reverse. Servicing of any object cannot begin before a predefined time moment; each object is also associated with an individual penalty which is a monotone increasing function of the moment when servicing ends. For the resulting optimization problems, we propose algorithms based on dynamic programming, give examples of their implementation, show results of numerical experiments; we study the computational complexity of these algorithms and the problems themselves.