Mechanized Placement of Drip Tape in Potato Comb

Over the past two years, decrease in potato yield has been observed in the Moscow region. One of the main reasons is unfavorable weather conditions. To obtain a guaranteed yield, as well as to improve the quality of products, it is necessary to carry out reclamation works, including additional irrigation. Creation of the optimal water - air balance of the plant throughout the entire growing season will increase productivity, and improve the quality of agricultural products. Drip irrigation is the most economical method of irrigation, but its widespread use is hindered by the high proportion of manual labor when installing the drip tape. A mechanized method of laying the drip tape by placing the working equipment on the Grimme GF-75/4 comb former is offered. The existing methods for determining the irrigation rate do not consider the parameters of the humidification circuit, which leads to excessive irrigation and additional losses of irrigation water. The paper offers a method for determining the irrigation rate considering the shape of the humidification circuit and its geometric parameters.

Loss Modeling of Large Hydrogenerators for Cost Estimation of Reactive Power Services

A new approach to predict the additional costs of reactive power system services delivered by large hydrogenerators is proposed in this letter. It is based on the application of the accumulated average efficiency (AAE), which has recently been proposed. An optimal operational path within the capability diagram with minimal losses is derived. This path can be used to calculate additional losses from operational regimes deviating from the optimal one for each active power level. Finally, the additional losses are accumulated in a similar manner as the AAE to estimate the extra cost of the operational regime, with ideal operation as the reference. In addition, the accuracy of a data clustering approach is explored to speed up the computation of the AAE and the accumulation of additional costs.

Loss Modeling of Large Hydrogenerators for Cost Estimation of Reactive Power Services

A new approach to predict the additional costs of reactive power system services delivered by large hydrogenerators is proposed in this letter. It is based on the application of the accumulated average efficiency (AAE), which has recently been proposed. An optimal operational path within the capability diagram with minimal losses is derived. This path can be used to calculate additional losses from operational regimes deviating from the optimal one for each active power level. Finally, the additional losses are accumulated in a similar manner as the AAE to estimate the extra cost of the operational regime, with ideal operation as the reference. In addition, the accuracy of a data clustering approach is explored to speed up the computation of the AAE and the accumulation of additional costs.

INVESTIGATION OF ADDITIONAL LOSSES OF FIBER-OPTIC CONDUCTORS OF TYPE G-652 THAT OCCUR DURING BENDING

One of the problems of modern information transmission systems is the introduction of new methods of protecting information transmitted over fiber-optic transmission lines. Currently, new methods of unauthorized access are emerging, which are being improved and developed every year. Within the framework of this work, studies of additional losses during bending of the optical fiber were carried out in order to create an automatic control system for additional losses that occur during mechanical action leading to its bending. For this purpose, practical experiments were conducted to measure losses in optical fiber with multiple bends and a computer program was created based on the data obtained. With the help of this program, it is possible to estimate additional losses in the optical fiber when the wavelength changes from 1310 to 1625 nm and the bending angle indicators from 45 to 135 degrees. The program also allows you to automatically approximate the values of additional losses occurring in the optical fiber with different variations of different bending angles and their number. The study of additional losses will allow in the future to develop an automatic control system based on changes in the indicators of additional losses and, when they change, issue a warning signal about possible unauthorized connection to a fiber-optic cable.

Series Architecture on Hybrid Electric Vehicles: A Review

The use of series architecture nowadays is mainly on hybrid buses. In comparison with series-parallel and parallel architectures, which are usually exploited on medium-size cars, the series architecture allows achieving internal combustion engine higher efficiency. The downside of this architecture, due to a double energy conversion (i.e., mechanical energy converted in electrical energy and electrical energy converted again in mechanical energy), is that additional losses are introduced. For this reason, the parallel and the series/parallel architectures were considered more suitable for hybrid medium-size cars. Nevertheless, the use of new technologies can change this scenario. Regarding storage systems, supercapacitors achieved a significant energy density, and they guarantee much higher efficiency than battery storage. Moreover, the use of wide-bandgap components for power electronic converters, such as silicon carbide devices, assure lower losses. In this scenario, the series architecture can become competitive on medium-size cars. This paper shows a review of various studies performed on this topic.

Wideband Coil Based on Microstrip Line for Multiheteronuclear Magnetic Resonance Spectroscopy

Magnetic Resonance Spectroscopy of X-nucleus is a method for mapping metabolite quantity in-vivo in the desired region of the human body. However, this method has a lot of difficulties. Since natural abundance of X-nucleus is much lower than for hydrogen, to improve SNR of the spectrum we need to work in higher static magnetic fields. But, even at such high fields, X-nuclei imaging still a very difficult process. One of the problems are RF-coils, which are required for transmission and reception of signals. Traditionally, for human body X-nuclei MRS multi-tuned loop coils are used. However, such coils suffer from additional losses in the circuits required for double-frequency tuning and high complexity. In this work, we propose an alternative approach, based on a recently introduced leaky-wave antenna for MRI, that allows creating wideband excitation which provides wideband transmit and receive. This wideband frequency range covering 13C, 23Na and 31P Larmor resonant frequencies.

Research of operating modes of conductors in power supply systems of cranes with induction feed, taking into account the influence of higher harmonics of the current

Purpose. Investigation of the influence of higher harmonics of current on current distribution, voltage and power losses in the supply systems of crane trolleys and development of a calculation method for practical use. Methodology. The analytical method and the results of the modeling method were used for research. Results. Analytical relationships have been obtained that make it possible to determine the current distribution, voltage and power losses in the systems of induction feeding of crane trolleys, taking into account the composition and amplitude of the higher harmonics of the current. Originality. For the first time, analytical dependences are obtained that take into account the effect of changing the trolley parameters on the frequency in the feed systems. Numerical values have been determined for the most commonly used induction feed systems for cranes. It is shown that with an increase in the cross-section of the feed bar there is a decrease in the main, and especially additional, losses. Practical value. Theoretical relationships have been obtained that can be used to calculate the optimization of induction feed systems in the presence of higher harmonic currents arising in power systems during operation of crane semiconductor controlled electric drives.

The Corona Phenomenon in Overhead Lines: Critical Overview of Most Common and Reliable Available Models

Research on corona discharge, shared by physics, chemistry and electrical engineering, has not arrested yet. As a dissipative process, the development of corona increases the resistive losses of transmission lines and enhances the line capacitance locally. Introducing additional losses and propagation delay, along the line, non-linearity and non-uniformity of the line parameters; therefore, corona should not be neglected. The present work is meant to provide the reader with comprehensive information on the corona macroscopic phenomenology and development, referring to the most relevant contributions in the literature on this subject. The models proposed in the literature for the simulation of the corona development are reviewed in detail, and sensitivity curves are provided to highlight their dependence on the input parameters.

SEMI-SUPERVISED SEGMENTATION OF CONCRETE AGGREGATE USING CONSENSUS REGULARISATION AND PRIOR GUIDANCE

In order to leverage and profit from unlabelled data, semi-supervised frameworks for semantic segmentation based on consistency training have been proven to be powerful tools to significantly improve the performance of purely supervised segmentation learning. However, the consensus principle behind consistency training has at least one drawback, which we identify in this paper: imbalanced label distributions within the data. To overcome the limitations of standard consistency training, we propose a novel semi-supervised framework for semantic segmentation, introducing additional losses based on prior knowledge. Specifically, we propose a lightweight architecture consisting of a shared encoder and a main decoder, which is trained in a supervised manner. An auxiliary decoder is added as additional branch in order to make use of unlabelled data based on consensus training, and we add additional constraints derived from prior information on the class distribution and on auto-encoder regularisation. Experiments performed on our concrete aggregate dataset presented in this paper demonstrate the effectiveness of the proposed approach, outperforming the segmentation results achieved by purely supervised segmentation and standard consistency training.

On the issue of occurrence of fire-hazardous situations with unbalanced power consumption

The influence of phase current unbalance on the probability of occurrence of fire-hazardous situations in industrial premises that receive power in various power supply systems is considered. The theoretical prerequisites for the occurrence of fire-hazardous situations are described. It is shown that zero-sequence flows flowing through a neutral conductor in an unbalanced mode significantly heat it, which can lead to short circuits and conditions for the occurrence of fires. The results of studies of unbalanced conditions in Russia and abroad are presented. It is shown that the zero-sequence flows resulting from current unbalance lead to an increase in additional losses of active power and electrical energy. It is proved that additional heat losses caused by unbalanced power consumption can destroy the insulation of neutral and phase conductors, which is the main cause of short circuits and, as a result, fires. Based on the use of the Matlab graphical editor, dynamic characteristics of variations in phase and interphase currents and voltages, as well as the power loss coefficient, which characterizes the increase in heat losses, are constructed. The analysis of fires and their consequences for various objects in the Russian Federation is made. A computational unit has been developed in Matlab, which is used for calculating and plotting the dynamics of fires and their consequences over the investigated period of time. It is shown that the occurrence of fires and their consequences due to violations of the rules of operation of electrical installations occurs in any premises and sometimes reaches more than 20% of all possible causes of fires. Methods and technical means of minimizing zero-sequence currents as a means of preventing the occurrence of fire-hazardous situations are considered. The principle of operation of an automatically controlled shunt-symmetric device with a minimum resistance to zero-sequence currents is described.