The study of the process of the development of marine robotics

Most projects of similar research are applied and become known mainly due to their commercial implementation. Undoubtedly, in the modern realities, it is more and more difficult to conduct scientific research regardless of the urgent production problems. Thus, cooperation of commercial structures, research institutions, military departments, etc. is required for the successful implementation of most projects. Certainly, the results of such projects can be effectively used by all the organizations listed above. For example, almost any innovation in the surveillance and search, under-ice and other studies in one form or another can be used for strategic or tactical military purposes

Construction of an algorithm for the analytical solution of the Kolmogorov-Feller equation with a nonlinear drift coefficient

The paper proposes a constructive method for solving the stationary Kolmogorov-Feller equation with a nonlinear drift coefficient. The corresponding algorithms are constructed and their convergence is justified. The basis of the proposed method is the application of the Fourier transform

Mathematical analysis of transport systems modeled by the stationary Kolmogorov-Feller equation with a nonlinear drift coefficient

The paper proposes the formulation of problems modeled with the stationary Kolmogorov-Feller equations with a nonlinear drift coefficient. Mathematical analysis of the model is given. The basis of the proposed method is the application of the Fourier transform to obtain analytical solutions to the problems under consideration

The use of fuzzy control methods for evaluation of complex systems on the example of maritime fleet equipment

At present, the interest in application of synchronous machines in the various systems of the electric drive and energy sources is still growing. Synchronous motors and their modifications enable to develop low-noise, reliable and economically efficient electric drive systems. They provide high maneuverability when using a propeller power plant of the submersible vehicles and the World fleet vessels. Synchronous generators are the major energy sources in the electric power systems of the variety autonomous plants: on vessels, offshore and coastal oil rigs, etc

Algorithmic approach of destabilizing factors of improving the technical systems efficiency

In work, the questions of stabilization of factors of reliability of operation of the ship equipment are considered. According to the Navy Register rules, ship electrical power system voltage fluctuations within ±10 % of the nominal voltage are admissible if not lasting longer than 5 seconds; longer fluctuations are admissible if they are within ±5 % of the nominal voltage. The work of the engine with loads is presented. The algorithm for parameter optimization was applied. The calculation is performed on real parameters

ALGORITHM DESIGN FOR SHIP’S STEERING WITH SPECIFIED LIMITATIONS UNDER VARIOUS WEATHER CONDITIONS

The problems of developing the risk assessment methods to estimate the level of safety of the vessel under the current conditions on a planned route before staring the pilotage as well as to make the decision on the beginning or suspension of pilotage in order to increase the level of navigational safety are discussed in the paper. Moreover, the application of the research results will reduce the affect of the human factor in decision-making in tasks related to the sea-going vessel’s operation. The developed method for the quantitative assessment of navigational risks will improve the safety of ship’s pilotage. It can also be applied in the decision-making support systems for the navigator in case of collision avoidance actions. The research results presented in this paper can be used to create automatic control systems

Modeling of Complex Structures for the Ship's Power Complex Using Xilinx System

One of the most essential tasks for a number of systems of the automatic controls in the autonomous electric power systems of the water transport is accurate calculation of variable harmonic components in the non-sinusoidal signal. In the autonomous electric power systems operating with full semiconductor capacity, the forms of line currents and voltages are greatly distorted, and generator devices generate voltage with inconsistent frequency, phase and amplitude. It makes calculation of harmonic composition of the distorted signals be a non-trivial task. The present paper provides a mathematical set for solution of the outlined problem including the realization in the discrete form. The simplicity and efficiency of the system proposed make possible to perform its practical realization with the help of cheap FPGA. The test of the developed system has been performed in the medium Matlab. The modern ship's electric power systems (SEPS) are characterized by the presence in its composition of a great number of the conversion load, including frequency transformer, un-interruptive power supply, inverters, rectifiers and other consuming devices varying in their non-linear volt-ampere features. Similar load has a negative impact on the supplying network of the alternating current, generating into it highest harmonic components of currents and voltages. At the same time, a great deal of the ship's automation systems apply the line currents and voltages to form the reference signal. Thus, for example, an automatic voltage regulator (AVR) of the ship's synchronous generators (SG) performs regulation by an average value of voltages and currents in the circuit. However, with the distorted form of the variable signals (that is caused by the presence of a wide range of highest harmonics) their average value increases and an automatic voltage regulator (AVR), correcting the error, decreases the exciting current of the synchronous generator that results in loss of voltage in the ship's electric power systems (SEPS). Consequently, decrease in relative value and increase in highest harmonics take place, and, thus, the electromagnetic moment of the non-synchronous motors decreases, the level of interferences influencing the systems of the ship's automatic controls becomes higher, and the losses in the power supply lines enlarge. Practically, such an error is corrected by the adjustment of the voltage corrector (VC). However, as the harmonic composition periodically varies depending on the mode of operation and the composition of the load of the electric power station, the setting of the voltage corrector should be changed constantly. This problem should be solved by measuring the level of the basic harmonics of the current and voltages of the ship's circuit. On the other side, it is known that filter-compensating devices (FCD) are the most efficient means to increase the quality of electric energy in the ship's power supply systems at the moment. Their efficiency in higher harmonic suppression and compensation of their volt-ampere reactive may be provided only by the high accuracy of the calculation of parameters in the target harmonics of the line currents and voltages. 2. Settlement of the problem Thus, the required functional set of the systems taken as an example determining their efficiency, in particular, and their operational performance in general, is a set for identification of external parameters of the control system. The major function of the block is extraction of harmonic components required for their analysis, calculation of their parameters from the distorted signal and application of the results of that analysis in the control of the means of the increasing values for quality of the electric Document type: Articl

The ability of flagellum-specific Proteus vulgaris bacteriophage PV22 to interact with Campylobacter jejuni flagella in culture

BACKGROUND: There has been a recent resurgent interest in bacteriophage biology. Research was initiated to examine Campylobacter jejuni-specific bacteriophage in the Russian Federation to develop alternative control measures for this pathogen. RESULTS: A C. jejuni flagellum-specific phage PV22 from Proteus vulgaris was identified in sewage drainage. This phage interacted with C. jejuni by attachment to flagella followed by translocation of the phage to the polar region of the bacterium up to the point of DNA injection. Electron microscopic examination revealed adsorption of PV22 on C. jejuni flagella after a five minute incubation of the phage and bacteria. A different phenomenon was observed after incubating the mix under the same conditions, but for twenty minutes or longer. Phage accumulated primarily on the surface of cells at sites where flagella originated. Interestingly, PV22 did not inject DNA into C. jejuni and PV22 did not produce lytic plaques on medium containing C. jejuni cells. The constant of velocity for PV22 adsorption on cells was 7 × 10(-9 )ml/min. CONCLUSION: It was demonstrated that a bacteriophage that productively infects P. vulgaris was able to bind C. jejuni and by a spot test that the growth of C. jejuni was reduced relative to control bacteria in the region of phage application. There may be two interesting applications of this effect. First, it may be possible to test phage PV22 as an antimicrobial agent to decrease C. jejuni colonization of the chicken intestine. Second, the phage could potentially be utilized for investigating biogenesis of C. jejuni flagella

SIMULATION AND SELECTION OF A PROTECTION TYPES IN THE DESIGN STAGE OF SHIPS AND OFFSHORE STRUCTURES

The requirements of the rules and regulations of the Classification Societies are based on the assumption that during the construction and operation of ships the hull corrosion protection measures are implemented according to the standards and other regulatory documents currently in force. For the purposes of designing the ship hull structures, the load components for different corrosion protection types have been obtained in the paper. There have been collected the data on the relationship between the corrosion protection weight load and the ship displacement, which enables to select the lowest corrosion protection type by weight. Technical and economic parameters of corrosion protection of ship hull structures have been analyzed. To achieve the objective of the paper a cumulative simplified approach of economic feasibility of selecting the corrosion protection type for ship hull structures has been employed. It has been determined that a total cost of protection from stress-corrosion fractures decreases for the ships with a displacement of more than 6000 [t] in the case of usage of the impressed current cathodic protection instead of the sacrificial anode cathodic one. The results of the investigation can be used by shipbuilders at the ship design stage, which enables to make a correct selection of a corrosion protection type and decreases its total cost

Comparison of Spider-Robot Information Models

The paper deduces a mathematical model of a spider-robot with six three-link limbs. Many limbs with a multi-link structure greatly complicate the process of synthesizing a model, since in total the robot has twenty-four degrees of freedom, i.e., three coordinates of the center of mass of the body in space, three angles of rotation of the body relative to its center of mass and three degrees of freedom for each limb, to describe the position of the links. The derived mathematical model is based on the Lagrange equations with a further transformation of the equations to the Cauchy normal form in a matrix form. To test the resulting model in a SimInTech environment, an information model is synthesized and two simple experiments ar carried out to simulate the behavior of real spiders: moving forward in a straight line and turning in place at a given angle. The experimental results demonstrate that the synthesized information model can well cope with the tasks and the mathematical model underlying it can be used for further research