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The problem of laboratory experiment automation, encountered by almost every experimenter, was considered in the paper. A great range of solutions is proposed by the industry. However, these solutions are rather sophisticated, expensive and do not offer a comprehensive approach to the problem solution. Therefore, the issue of developing software and hardware platform for laboratory experiment automation with minimum time, force and means expenditures is topical nowadays. The ultimate objective of the paper is development and implementation of software and hardware platform for experiment control and data gathering and processing. The principle requirements for the platform include simplicity of design and use, portability and low cost. The platform developed consists of three main blocks: an interface of stepper motors, data gathering system and software for digital signal processing and creation of client application for PC. The interface of stepper motors includes control unit for stepper motors drivers, which is connected to PC via COM port, and stepper motors drivers themselves, which allow implementing a micro step up to 1/32 of nominal step of stepper motor. Any analog-to-digital converter can be used as measuring instrument. In this case, standard PC audio card was chosen as the most affordable and cheap device for measuring signals with admissible metrological characteristics. Software synchronous detector was applied for reducing the influence of background noise on the measured signal. It allows measuring signals with error not exceeding 1% and signal-to-noise ratio 10dB. [ABSTRACT FROM AUTHOR]

The problem of obtaining information redundancy contained in random, generally nonstationary by the mathematical expectation dynamic processes under control was considered in the paper. A mathematical model of predicting critical emissions in random atmosphere pollution processes with the correction to asymmetry of the processes was proposed. The procedure of testing a multicomponent pollution process by parameters during a multivariable control considering its extrapolated values was described. An algorithm of a parametric significance test concerning stationarity violations with regard to risks of the first type control was developed. The test implements a procedure of verifying statistical hypotheses. This approach allows using the extrapolation model, adjusted towards the mathematical expectation, reducing risks of the second-type control. The research results, described in this paper can be used by specialists in the field of ecological control and monitoring, as well as in information systems and technologies. [ABSTRACT FROM AUTHOR]

In this paper, it is proposed to use the midfrequency of the emissions of the controlled parameters as a criterion for environmental control of the gaseous emissions and liquid discharges of the energyintensive enterprises. A mathematical model of the midfrequency of the emissions of the controlled pollution process as the sum of the amplitude and phase components is considered. Analytical expressions of these components are obtained. Graphical interpretations of the components for optimizing the control and preventive limits, and intervals for a minimum criterion of the midfrequency of the emissions are analyzed. Experimental use of the model of the midfrequency of the emissions during the active control of the concentrations of sulfur oxide in the power plant emissions is considered. The obtained results allow adjusting the control and preventive limits and optimally organizing them during planning. Using this model increases the reliability, sensitivity of control to prevent the violations of natural resource management. [ABSTRACT FROM AUTHOR]

The differences between the existing technologies of traffic light control by phases and signal groups were determined in the paper. It was proved that the signal group control technology is more perfect and to a greater extent corresponds to the changing traffic conditions at intersections. Approach for compiling the traffic light regulation cycle structure based on the analysis of conflict of traffic and pedestrian flows, taking into account traffic volume, the number of road accidents in the conflict zones was defined. Also, in compiling the structure, the need to reduce the delays of vehicles and pedestrians was taken into account. Based on the signal group control technology, an algorithm for determining the parameters of traffic light regime, taking into account the traffic light cycle structure optimization, compiled for implementation on a computer was proposed. Using the developed approach will allow to increase the efficiency of traffic light regulation in both improving the traffic safety of vehicles and pedestrians and in reducing their delays before intersections. [ABSTRACT FROM AUTHOR]

The analysis of methods for rotation speed control of direct-current traction motors with the series and compound excitation is conducted in the paper. The scheme to improve energy efficiency of speed control devices of traction electric motors of public electric transport rolling stock is proposed. The proposed scheme using the increasing DC-DC converter allows to perform a smooth TEM field weakening, improve the shunt coil copper use and reduce electric power consumption at starting the rolling stock. In this case, weakening the compound excitation TEM field is conducted by changing the current in both series, due to the input converter circuit, and shunt coil. Moreover, current control in the shunt coil, the magnetizing force of which is directed opposite the magnetizing force of the series coil, is performed due to the output converter circuit. The electrical schematic diagram of the test stand and results of studying the proposed field weakening method are proposed. [ABSTRACT FROM AUTHOR]