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Introduction: With the rapid development of human society and economy, the power generation technology of various new energy vehicles has begun to receive widespread attention. Methods: Due to the lack of inertia and frequency stability in the new energy vehicle power generation system, this paper proposes a power generation control method that combines linear active disturbance rejection control technology and virtual synchronous generator technology. This method first introduces the control strategy and inertial response of the virtual synchronous generator. Then, it uses linear active disturbance rejection control technology to improve the virtual synchronous generator technology to deal with the uncertainty and external interference in the system. Results: The results showed that when the virtual inertia coefficient was 0, and the new energy vehicles would hardly intervene in the regulation of the grid voltage. When the virtual inertia coefficient was 5, the decline rate of the DC bus voltage of new energy vehicles had slowed down. When the virtual inertia coefficient increased, the power output of new energy vehicles can be increased to the grid. When the load suddenly increased, and the corresponding DC bus voltage decreased more slowly. In the VSG output power comparison, under the research method, the frequency fluctuation only increased by 0.09 Hz and returned to the rated frequency of 50 Hz. Additionally, the dynamic process of the system output power was the shortest, lasting only 0.05 s. Discussion: The above results show that the research method has significant superiority and effectiveness in improving the inertial response and overall stability of the new energy vehicle power system. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles are a synergistic technology that complements other new technologies and is in constant development. The paper focuses on using artificial intelligence (AI) in security surveillance. This article aims to develop an unmanned aerial system to monitor border areas and detect human silhouettes in challenging environmental conditions. For this purpose, thermal imaging technology was used for remote sensing in combination with artificial intelligence, particularly Yolo algorithms. After testing various Yolo versions, the target algorithm was implemented on an NVIDIA Jetson Xavier NX edge device. Prototyping of the AI-based thermal detection system was carried out on the DJI S900 multi-rotor aircraft. The final solution was implemented on a vertical take-off and landing aircraft. A summary containing observations and conclusions, as well as perspectives for the development of future work, are included at the end of the paper. [ABSTRACT FROM AUTHOR]

Sowing depth is a critical factor in crop growth and is determined by both the soil conditions and the force of the opener. The trend for the future is to control sowing depth based on soil dynamic parameters. Therefore, this paper developed a downforce measurement and control system based on the 'T'-shaped furrow opener and investigated the influence of soil dynamic parameters and opener downforce on sowing depth. A test-rig was constructed and the accuracy of the system in measuring downforce and controlling downforce and sowing depth was verified. The study shows that at different sowing depths, soil moisture, bulk density and their interaction have a significant effect on downforce (P < 0.01). As the moisture content decreases and the bulk density increases, the required downforce increases for the same sowing depth. A mathematical model of downforce-sowing depth-soil bulk density-soil moisture content was established using experimental data, with an R2 of 0.916, VIF <5 and a Durbin-Watson value of 1.628. Field experiments show that, at an operating speed of 6 km h−1, the control strategy based on the soil dynamic parameters predicted by downforce theory significantly outperformed the strategy of adjusting the downforce in response to perceived changes in downforce. This indicates that after dynamic and rapid measurement of soil bulk density and moisture content during field operations, sowing depth can be accurately controlled based on the directed downforce of the opener. The mathematical model provides a theoretical basis for sowing depth control based on soil dynamic parameters. • Proposing a sowing depth control strategy based on soil dynamic parameters. • System developed under static conditions and validated through dynamic experiments. • A mathematical model for the precise control of sowing depth was established. [ABSTRACT FROM AUTHOR]

Electric Arc Furnaces (EAFs) are widely used in the steel manufacturing industry to melt scrap steel by employing a large number of electric arcs. EAFs play an important role in ensuring the efficient production of steel. However, their nonlinear and variable load characteristics have a significant impact on power quality. Because the active power of an electric arc depends on its length, a system for controlling the electrode positions is necessary. This paper presents a control system based on a fuzzy logic controller for the active power control of an electric arc furnace. Individual simulation scenarios were chosen with both reference values and the process taken into consideration. The reference, constant value, step variation, and the sequence of step variation were investigated, as well as step disturbances and the sequence of step disturbances from the viewpoint of the process. Furthermore, the procedure of changing the tap on a transformer was investigated. The proposed solution minimizes the time required for charge elaboration, but the main benefit is that there are no additional costs in the implementation process because the installation remains identical, with the only changes being improvements to soft control management. [ABSTRACT FROM AUTHOR]

Marine engineering officers operate and maintain the ship's machinery during normal navigation. Most accidents on board are related to human factors which, at the same time, are associated with the workload of the crew members and the working environment. The number of alarms is so high that, most of the time, instead of helping to prevent accidents, it causes more stress for crew members, which can result in accidents. Convolutional Neural Networks (CNNs) are being employed in the recognition of images, which depends on the quality of the images, the image recognition algorithm, and the very complex configuration of the neural network. This research study aims to develop a user-friendly image recognition tool that may act as a visual sensor of alarms adjusted to the particular needs of the ship operator. To achieve this, a marine engineering simulator was employed to develop an image recognition tool that advises marine engineering officers when they are conducting their maintenance activities, with the aim to reduce their stress as a work risk prevention tool. Results showed adequate accuracy for three-layer Convolutional Neural Networks and balanced data, and the use of external cameras stands out for user-friendly applications. [ABSTRACT FROM AUTHOR]

Objective: To explore the relationship between parental mediation and adolescents' tendency of online game addiction, and the effect of self-control in it. Methods: Totally 553 senior high school students were tested with the Chinese version of Parental Mediation of Online Activities Questionnaire, Internet Gaming Disorder Scale-Short-form (IGDS9-SF) and Dual-mode of Self-control Scale for Adolescents (DMSC-S). Parental active mediation, restrictive mediation, Internet game addictive tendency, adolescent self-control impulsive system, control system were evaluated respectively. SPSS macro program PROCESS was used to test the mediating role. Results: The scores of restrictive mediation of parents were negatively associated with the scores of adolescents' tendency of online game addiction (β= 0. 14, P <0.001). Self-control scores played an independent mediating role between parental active mediation scores and online game addiction tendency scores (indirect effect = 0.09,95% CI = 0.090.01) and a partial mediating role between parental restrictive mediation scores and online game addiction tendency scores (indirect effect = 0.04,95% CI =0.00-0.07). Conclusion: Parental active and restrictive mediation are related to adolescents' tendency of online game addiction. Self-control plays a partial mediating role. [ABSTRACT FROM AUTHOR]

The article deals with the design of the educational model of the robot, where, in addition to kinematics, the control system of the robot and the simulation of the robot's activity in the GAZEBO environment are also addressed. Students can train different control algorithms on this model. At the same time, a graphical interface for simulating the robot's activity is also created. The control system is composed of a low-cost embedded Arduino system, which is very easy to program and create control systems. Simulations and experiments showed the correctness of the design methodology of such a robot model. [ABSTRACT FROM AUTHOR]

Even for short space flights, such as manned flights to the Moon back in the 60s, it became extremely obvious that electric batteries are completely unsuitable because of their huge mass needed to store the required supply of onboard energy. Therefore, already in the 60s of the last century, the USA and the USSR took the path of using a hydrogen storage system using hydrogen fuel cells. Solar-hydrogen energy systems for spacecraft reliably provide energy for carrying out various kinds of unscheduled work on board and for eliminating emergency situations. Surplus energy is constantly accumulated on board in the form of the chemical energy of cryogenic hydrogen. The article presents too the result of the development of a solar-hydrogen power supply system for spacecraft, the onboard network of which provides slow and fast processes. This paper delves into designing digital control systems for power conditioning devices on the example of charging-discharging device based on a boost DC-DC converter. The device was implemented to condition a storage battery by properly charging and discharging it. A technique for constructing a small signal model of the converter has been developed. This involves constructing a block diagram using the discontinuous switching functions and analog models of electrical circuit components. The transfer functions of the analog controllers for the two-loop subordinate control system were derived. Then the procedure of a bilinear z-transform to the given transfer functions was applied. As a result, the discrete transfer functions of the digital controllers were obtained. Realization both analog and digital controllers in Matlab Simulink confirmed their identical behavior and stability within the power converter. Experimental studies of the static and dynamic waveforms of the digital control system showed controllability and stability of the charging-discharging device for the storage battery in typical operating modes. Thus, the method of synthesizing digital control systems for energy converters is proved valid and applicable for designing new power conditioning devices within modern power supplies. [ABSTRACT FROM AUTHOR]

In recent times, renewable energy sources have gained significant popularity because of the dwindling reserves of fossil fuels and the significant environmental damage resulting from their use. Among the various renewable energy sources, hydrogen stands out as one of the most crucial technologies for the future. Hydrogen can be produced through several different methods, and electrolysis is among the most frequently used methods. This method employs electrical energy to decompose water into its constituent hydrogen and oxygen molecules. When this electrical energy is derived from renewable sources such as solar or wind, then green hydrogen is produced. Systems that use electrolysis to produce hydrogen are known as electrolyzers. One of the primary challenges in the electrolysis process is ensuring the purity of hydrogen; proper control of the levels and pressures of the gas tanks can improve this purity. Automatic control strategies are very important for regulating the levels and pressures of the oxygen and hydrogen tanks. Researchers have proposed various classical techniques for controller design to mitigate this issue. This study seeks to offer a comprehensive and up-to-date review of existing research on control methods for alkaline electrolyzers, which has attracted considerable attention in recent times. The findings of this review offer valuable insight for future studies aimed at developing new control strategies to enhance hydrogen purity. • Describe main control strategies applied to alkaline electrolyzers. • Comparison of control strategies applied to electrolyzers and finding gaps in the literature. • Describe the importance of hydrogen purity and its production control methods. • Identify applications of alkaline electrolyzers according to the control strategy. • Importance of electrolyzers with renewable energy sources as an energy vector. [ABSTRACT FROM AUTHOR]

Current trends in industries related to autonomous, mobile objects, such as aircraft manufacturing, are aimed at increasing the share of electrification or completely replacing all units in favor of electric ones. Replacing components and assemblies with fully electric ones corresponds to the concept of a fully electric aircraft, which is based on new power sources and sources of electric propulsion, such as lithium-ion batteries, hydrogen batteries, and sources based on renewable energy. At the same time, the requirements for energy efficiency and weight and size parameters of components and assemblies are increasing. These needs can be met through the multi-purpose use of equipment, as well as through new systems that combine a number of functions. The article discusses the use of an aircraft three-stage synchronous generator as a starting device for a gas turbine engine. The problems associated with the use of a three-stage generator are analyzed and a method for solving them is proposed. The article presents a method for creating a starting torque using the reactive component of the electromagnetic torque for a synchronous salient pole generator. The analysis was carried out from the point of view of the formation of electromagnetic torque in an aircraft generator using a voltage inverter. A generalized expression for the torque is obtained, regulated and controlled by the electrical parameters of the frequency converter. [ABSTRACT FROM AUTHOR]

In recent years, Japan has experienced numerous natural disasters, such as typhoons and earthquakes. Teleoperated ground robots (including construction equipment) are effective tools for restoration work at disaster sites and other locations that are dangerous and inaccessible to humans. Using visual information obtained from various viewpoints by a drone can allow for more effective remote control of a teleoperated ground robot, making it easier for the robot to perform a task. We previously proposed and developed a remote-controlled drone system using only human eyes. However, the effectiveness of using this drone system during the remote control of a robot has never been verified. In this paper, as the first step in verifying the effectiveness of the remote-controlled drone system using only the eyes when remote-controlling a robot, we consider its effectiveness in a simple task based on the task times, subjects' eye fatigue, and subjective evaluations of subjects. First, the previously proposed drone system is briefly described. Next, we describe an experiment in which a drone was controlled by the eyes using the drone system while a robot was controlled by hand, and an experiment in which both the drone and robot were controlled by hand without using the drone system. Based on the experimental results, we evaluate the effectiveness of the remote-controlled drone system using only the eyes when remote-controlling a robot. [ABSTRACT FROM AUTHOR]

In this study, we investigated inspection robots that can safely, accurately, and quickly perform hammer sound inspections on tile exterior walls and present new wall hammering inspection systems using two-wheeled multi-copters. Our results yielded the following five advantages. First, the proposed multi-copter can use its wheels not only to move freely on the walls of buildings but also to overcome obstacles on the walls. Therefore, almost any tile wall surface can be inspected for hammering sound. Second, the multi-copter was equipped with both hammer-shaped rods to hit the tile exterior wall and microphones to collect the hammer sound of the tile, while moving quickly on the wall surface. Third, the wall hammering inspection systems can be used safely with a work assistance mechanism using a wire even in densely populated areas, such as urban areas, because the multi-copter has high wind resistance against crosswinds by both pushing against the wall and operating by the wire. Fourth, we presented some automatic control systems that make the multi-copter operation easy during hammering inspections and demonstrated its usefulness through experiments. Fifth, we proposed useful methods for detecting floating tiles based on the hammering results, conducted some outdoor flight experiments on building exterior walls, and demonstrated that floating tiles can be determined with high accuracy. [ABSTRACT FROM AUTHOR]

Robotic grasping is a common operation scenario in industry and agriculture, in which the force sensing function is a significant factor to achieve reliable grasping. Existing force sensing methods of flexible grippers require intelligent materials or force sensors embedded in the flexible gripper, which causes such problems of higher manufacturing requirements and contact surface properties changing. In this paper, a novel rope-driven force sensing flexible gripper is designed based on the fin-shaped gripper structure, which can realize the grasping sensing functions of contact nodes and contact forces without the need for force sensors. Firstly, the rope-driven force sensing flexible gripper is designed, including the driving unit, the transmission part, the gripper unit, and the force sensing unit. The force sensing unit and the gripper unit are connected by rope, and the prototype of the rope-driven force sensing flexible gripper is completed. Secondly, a force sensing algorithm and control system based on finite element method and grasping geometric relationship are designed to realize the rope-driven force sensing flexible gripper grasping control and sensor data acquisition and processing. Finally, the experimental system of the rope-driven force sensing flexible gripper is built, and the grasping experimental tests of objects with different diameters and different contact nodes are carried out to verify the force sensing function of the rope-driven force sensing flexible gripper. The force sensing flexible gripper designed in this paper can provide a new idea for the design and force sensing method of intelligent robotic grasping system in robotic teaching, scientific research, and industrial applications. [ABSTRACT FROM AUTHOR]

In non-residential buildings, building energy management systems (BEMS) and the application of data hold significant promise in reducing energy consumption. Nevertheless, BEMS have different levels of complexity, benefit, and limitation. Despite the advanced technologies and improvements in building operation, there is a clear gap in the actual performance of buildings that has been attributed to the adoption of advanced technologies. Consequently, there is an increasing need for researchers and practitioners to study current practices in order to identify and address the challenges that compromise the core objectives of BEMS. For this reason, this paper aims to validate three research questions: (i) to examine the current state of BEMS and its functionalities; (ii) to analyze the type of control used; (iii) and to determine the availability of historical data compiled by BEMS and its application in non-residential buildings. A survey of 676 buildings and interviews with building professionals were conducted. The findings confirmed that most of the buildings applied BEMS with scheduled control. In addition, a lack of digitized data for analysis and predictions was detected. Indeed, only 0.60% of the investigated buildings implemented predictive control. Finally, using hierarchical clustering analysis, responses were grouped to analyze similarities between them. The study findings help to develop targeted actions for implementing predictive control in non-residential buildings. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural technology with a hydroponic system provides an alternative for farmers and communities who have limited land. This research aims to make innovations with a hydroponic monitoring system that can be done remotely via the internet that combines 2 systems, namely horizontal technique and nutrient film technique (NFT). The sample used in this study was curly mustard seeds. To combine the 2 systems, researchers designed a hydroponic prototype system using internet of things (IoT) in the form of smart hydroponics in the Blynk application. This research uses literature studies for research reference and flowcharts to regulate the flow of the program to be researched. The results showed that by using the IoT and the Blynk application, owners can monitor the nutrient content and pH of curly mustard greens remotely. The system automatically controls nutrients and pH according to the desired settings. In the growth control system of mustard curly, the use of smart hydroponics is proven to be better. Harvestable plants at the age of 34 days. Unlike the conventional system, the harvest period is at the age of 40-45 days. Therefore, smart hydroponics is more efficient because it shortens the harvesting time and saves labor. [ABSTRACT FROM AUTHOR]

In air conditioning systems, air curtains play a crucial role in reducing the exchange of hot and cold air between the interior and exterior environments. Nevertheless, the majority of current air curtains suffer from limited airtightness and real-time performance due to their complex jet trajectory, relying on traditional control methods. Thus, this paper introduces an angle control algorithm for air curtains based on a GA-optimized quadratic BP neural network. Initially, the BP neural network is trained using the Hayes dataset to develop the prediction model for temperature-jet angle. Subsequently, the optimization model for jet angles-windshield angle is constructed, and the optimal angles set meeting the fitness function is identified using GA global search. Later, the prediction model and the optimal angles set are once again trained using the BP neural network to generate prediction model for temperature-jet angles and windshield angle. Following CFD simulation, the airtightness indicator demonstrated a 26.5% improvement with the proposed control method compared to traditional ones, highlighting the superior airtightness. In comparison to other algorithms, the proposed algorithm demonstrates a remarkable 89% enhancement in real-time performance and stronger robustness. This study presents a novel approach for the intelligent control of air curtains, holding significant importance in advancing the intelligent development of air curtain technology and facilitating energy efficiency and emission reduction. [ABSTRACT FROM AUTHOR]

Compared to agricultural environments, afforestation sites are more complex, often presenting issues such as undulating and uneven terrain. These conditions lead to instability in hole digging depth and plant spacing during continuous movement, and the hole shape may not meet expectations. Additionally, the hydraulic system exhibits slow response speed and long steady-state time, affecting the quality of sapling planting. To address these issues, this paper designs an intelligent planting control system for intermittent hole digging under continuous dynamic movement, based on a large tree planter. The focus is on studying the dynamic accuracy of the hole digging cylinder to resolve the instability of plant spacing and planting depth in actual planting processes. Firstly, a motion trajectory model of the intermittent hole digging mechanism is established to obtain the relationship between the displacement trajectory of the rotating cutter and the displacements of the floating cylinder and the hole digging cylinder. Secondly, a mathematical model of the electro-hydraulic servo system is established to control the dynamic accuracy of the hole digging operation. Finally, a Simulink simulation model of the system is established to analyze the performance indicators of the hydraulic system during operation using step and sinusoidal excitation signals. The test results show that the displacement of the hydraulic piston rod can ensure a linear extension trend within the range of 0 to 0.4 m, and the extension distance of the hole digging cylinder in the planting system is 0 to 0.35 m, ensuring linear change within this stroke. When the system's extension command is 1 V, the actual output is 0.6 m, with a relative error of less than 10% compared to the simulation value, indicating that the control strategy can effectively improve the dynamic performance of the system. When the hydraulic system is in a steady-state extension state at 50 to 58.6 s, the relative error with the simulation value is 7.3%, meeting the "double ten indicators" requirement. The research results clearly verify the superior performance of the proposed intelligent control system, and the proposed control strategy has great potential in practical applications, promising to improve afforestation quality by stabilizing planting spacing and planting depth. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the formation isolation regulation issue regarding multiple Autonomous Underwater Vehicles (AUVs) characterized by a "leader–follower" framework. Considering the cooperative–competitive relationship among the follower AUVs and the impact of unknown external disturbances, an extended state observer is designed based on backstepping to mitigate these disturbances, and an event-triggered control scheme is designed to realize the two-part consensus control within the multi-AUV system. Through rigorous theoretical analysis, it is shown that the system achieves asymptotic steadiness and is free from Zeno behavior under the proposed event-triggered control scheme. Finally, numerical simulations confirm the efficiency of the regulation strategy in achieving formation separation within the multi-AUV, where the trajectory tracking errors of individual AUVs gather in a compact vicinity close to the source, and the structure convergence is achieved, with the absence of Zeno behavior also demonstrated. [ABSTRACT FROM AUTHOR]

BACKGROUND: In order to address the issues of uneven pesticide deposition and low pesticide utilization in rubber gardens caused by the traditional diffuse plant protection spraying method, this study focuses on the air‐assisted powder sprayer and proposes a variable pesticide application control system. A variable pesticide application decision‐making model integrating the leaf area index (LAI) was designed based on powdery mildew control standards and individual rubber tree information. According to the target powder spraying accuracy requirements, a control model of the air velocity adjustment device was established and a fuzzy proportional‐integral‐differential (PID) air velocity control system was developed. RESULTS: The simulation results indicate that the wind speed control system exhibits a maximum overshoot of 2.18% and an average response time of 1.48 s. The field experiment conducted in a rubber plantation revealed that when the air‐assisted powder sprayer operates in the variable powder spraying mode, the average response time of the control system is 2.5 s. The control accuracy of each executive mechanism exceeded 95.9%. The deposition coefficient of variation (CV) at different canopy heights was relatively consistent, with values of 35.38%, 36.26% and 36.90%. In comparison to the quantitative mode, the variable mode showed a significant 20.03% increase in the effective utilization rate of sulfur powder. CONCLUSION: These research findings provide valuable technical support for the advancement of mechanized variable powder spraying equipment in rubber tree cultivation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The ever-growing concerns about global warming and the rapid depletion of fossil fuels have triggered a rising interest in the research for cleaner, more efficient, and cost-effective energy generation. Organic Rankine cycle systems have immense potential to become a strong alternative to conventional methods of energy generation. However, such systems' efficiency is limited by the performance of the incorporated gas expanders or prime movers. Conventional gas expanders often utilize ports or cam-operated valves. Ported expanders offer limited efficiency and controllability and produce high emissions, causing a large amount of heated and compressed gas to be wasted. Cam-operated valves, in contrast, increase expansion performance compared to ported expanders; however, they have no variability and adaptability to changes in system parameters such as gas pressure, temperature, dryness fraction, and load variation, to name a few. On a positive note, this issue can be addressed by adopting a variable timing and fast-operating, control valve with an accurate and adaptive control mechanism at the expander inlet. A properly designed and controlled valve can greatly improve the system performance of gas expanders and pave the way for an efficient low-cost alternative energy generation. This manuscript provides a comparative review of recent progress on the design, modeling, optimization, and control aspects of valves for gas expanders. A clear pathway on the scope of further development is also drawn based on the present state of the art. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A multilevel-multiphase topology based on modified Cuk converter is proposed in this paper. This paper employs the combination of multiphase and multilevel topology which is applied to the modified dc-dc the Cuk converter serves as the fundamental cell topology to achieve low-ripple high-ratio DC-DC converter. The multiphase approach will generate smaller current ripples in the input and output sides so it will be beneficial for ripple-prone sources or load, for example photovoltaic panel or battery. Meanwhile, the multilevel approach will generate high ratio amplification for input voltage, provided by PV panel or battery, to reach typical 380-400VDC in the output voltage which is suitable for DC microgrid applications. A four levels multilevel-multiphase modified Cuk converter topology is successfully developed. The derivation of the mathematical expression of the voltages applicable to the proposed converter is conducted. Loss analysis is conducted to observe the contributing factor of losses to the total efficiency is conducted. A double-loop control system is proposed for the proposed converter to achieve the desired reference operation point for various conditions. It can be demonstrated that the proposed converter generates high ratio total output voltage while maintaining notably small current ripple. Simulation and experiment are conducted to verify the performance of the proposed converter. [ABSTRACT FROM AUTHOR]

Gas purification in ferroalloy furnaces is vital for the efficiency and quality of the entire production process. To enhance the efficiency of the gas purification system, an upgrade to the bag filter regeneration control system has been proposed. Using the SimInTech dynamic modeling environment, the performance of the control system was evaluated before and after modernization. Key quality indicators and misalignment errors were calculated to assess the proposed engineering solution. The speed increased by 3.8 times, reducing response time to 2.9 s, the stability increased by 3 times, achieving a stability degree of 1.05, the reliability of the control system increased by 4.2%, reaching a reliability rate of 96.3%, and the misalignment error decreased by 30 s, resulting in a misalignment error of 25 s. Operational data from the Aktobe Ferroalloy Plant were used to assess the impact of the modernization on productivity, energy efficiency, and the overall quality of the gas purification system. The average efficiency coefficient of the regeneration system was determined to be 34.75%. [ABSTRACT FROM AUTHOR]

Four control systems are generated using Matlab software based on different regulators for the granulation process in a fluidized bed: PID controller and optimal LQR for linear systems and MPC and those based on fuzzy logic for nonlinear systems. For each control system, transient characteristics are obtained and system efficiency indicators are given. [ABSTRACT FROM AUTHOR]

Introduction. In accordance with one of the ways of solving the problem of increasing the smoothness of the vehicles, a controlled suspension is proposed, which is created on the basis of the use of «smart» materials – magnetorheological elastomers, the mechanical properties of which, in particular, damping, can be changed with the help of a controlling magnetic field. This is implemented with the help of the magnetorheological actuator of the suspension control system, which has the form of an elastic bushing of the suspension arm, consisting of several electrically connected in series toroid-like coils (with a core of magnetorheological elastomer). The device is powered by current, the value of which is controlled by the operator, or automatically, depending on the road profile and driving mode. Magnetorheological actuators (elastic bushings) are placed in the holes of the suspension levers instead of standard rubber ones and combined with a controlled current source. Thus, the suspension becomes controllable, which makes it possible to set the necessary vibration damping of the vehicle body to increase its smoothness. Problem. The disadvantage of the previous designs of the magnetorheological actuator is the insufficient amount of the magnetic flux density and the unevenness of its distribution within the elastic bushings. As a result, the damping properties of such controlled suspensions become insufficiently effective, which reduces the possibility of increasing the smoothness of the vehicles. The purpose of the work is to increase the damping properties of the magnetorheological actuator of the vehicle suspension control system, which will increase the control efficiency. The task is to improve the design of the performing magnetorheological device, to carry out calculations and develop a calculation scheme of the study, to determine the average magnetic flux density value and its distribution across the crosssection of the device, to calculate the dependence of the device damping indicator on the magnetic flux density, to compare the damping indicators of the improved device with previously known ones. Methodology. Research tasks were solved on the basis of magnetic field analysis using methods of magnetic field theory and SOLIDWORKS® and FEMM software packages, as well as analysis of the dependence of the damping properties of bushings from magnetorheological elastomers on magnetic flux density. A description of the design and principle of operation of the magnetorheological actuator of the vehicle suspension characteristics control system is given, based on which the calculation scheme was developed. Results. The results of research calculations showed that the average value of magnetic flux density in the proposed design of the device reached 0.85 T, its distribution became fairly uniform, and there were no zones where it was abnormally small. For the first time, the dependence of the damping index on the magnetic flux density of the controlling magnetic field has signs of scientific novelty. It was found that this indicator for the proposed design of the device increased by 22 % compared to previous other designs, which will increase the efficiency of the control system and the smoothness of the vehicle. A positive result was achieved due to the following features of the proposed design of the suspension actuator: the elastic sleeve consists of several coaxially located actuators made of anisotropic magnetorheological elastomer, in which the conglomerates of the ferromagnetic filler during the manufacturing process are located collinear to the direction of the angular deformations of the sleeve and the control magnetic field flux density vector, and the devices have control coils located on their surfaces, which are made of conductive elastic elastomer and electrically connected in a series circuit. Originality. The control method, previous designs and construction of this controlled suspension are protected by patents of Ukraine. Practical value. The direction of further research is to optimize the parameters of the control coils in order to reduce the energy consumption for them and to protect them from overheating. References 20, figures 10. [ABSTRACT FROM AUTHOR]

Four control systems are generated using Matlab software based on different controllers for the granulation process in a fluidized bed: controllers for linear systems — PID and optimal LQR, controllers for nonlinear systems — MPC and those based on fuzzy logic. For each control system, transient characteristics are obtained and system efficiency indicators are given. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose. To analyze the energy saving reserves under the conditions of implementation and integration of the system in order to find rational driving modes in the general system of managing underground electrified transport. Methodology. The work presents the method for processing data arrays obtained experimentally with the help of a measuring system and theoretically with the use of the “Rational Trajectory” software. Findings. Experimental studies were carried out using a testing system created on the basis of a refurbished train with energy recovery system. Theoretical studies were carried out using the “Rational Trajectory” software, which is based on the principle of solving a multi-criteria problem by the method of the main criterion. The minimum amount of electricity consumption from the overhead contact line was chosen as the main criterion. The software was developed in the LabVIEW graphical programming environment in order to determine the rational modes of driving rolling stock and energy indicators in a given area of its operation. The amount of electricity consumed for traction and the amount of electricity generated by the train during regenerative braking were determined based on the results of experimental and theoretical studies, respectively, under typical and rational modes of driving the train for given identical operating conditions. Originality. Further research on the analysis of energy saving reserves on the rolling stock of underground electrified transport was achieved due to the introduction of a system for finding a rational driving mode. Practical value. It has been established that the implementation and incorporation of the “Rational Trajectory” software into the train control system will save up to 14.7 % of the amount of electricity consumed for traction, compared to typical modes operation on a given track section. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles are a synergistic technology that complements other new technologies and is in constant development. The paper focuses on using artificial intelligence (AI) in security surveillance. This article aims to develop an unmanned aerial system to monitor border areas and detect human silhouettes in challenging environmental conditions. For this purpose, thermal imaging technology was used for remote sensing in combination with artificial intelligence, particularly Yolo algorithms. After testing various Yolo versions, the target algorithm was implemented on an NVIDIA Jetson Xavier edge device. Prototyping of the AI-based thermal detection system was carried out on the DJI S900 multi-rotor aircraft. The final solution was implemented on a vertical take-off and landing aircraft. A summary containing observations and conclusions, as well as perspectives for the development of future work, are included at the end of the paper.

Introduction. In accordance with one of the ways of solving the problem of increasing the smoothness of the vehicles, a controlled suspension is proposed, which is created on the basis of the use of «smart» materials – magnetorheological elastomers, the mechanical properties of which, in particular, damping, can be changed with the help of a controlling magnetic field. This is implemented with the help of the magnetorheological actuator of the suspension control system, which has the form of an elastic bushing of the suspension arm, consisting of several electrically connected in series toroid-like coils (with a core of magnetorheological elastomer). The device is powered by current, the value of which is controlled by the operator, or automatically, depending on the road profile and driving mode. Magnetorheological actuators (elastic bushings) are placed in the holes of the suspension levers instead of standard rubber ones and combined with a controlled current source. Thus, the suspension becomes controllable, which makes it possible to set the necessary vibration damping of the vehicle body to increase its smoothness. Problem. The disadvantage of the previous designs of the magnetorheological actuator is the insufficient amount of the magnetic flux density and the unevenness of its distribution within the elastic bushings. As a result, the damping properties of such controlled suspensions become insufficiently effective, which reduces the possibility of increasing the smoothness of the vehicles. The purpose of the work is to increase the damping properties of the magnetorheological actuator of the vehicle suspension control system, which will increase the control efficiency. The task is to improve the design of the performing magnetorheological device, to carry out calculations and develop a calculation scheme of the study, to determine the average magnetic flux density value and its distribution across the cross-section of the device, to calculate the dependence of the device damping indicator on the magnetic flux density, to compare the damping indicators of the improved device with previously known ones. Methodology. Research tasks were solved on the basis of magnetic field analysis using methods of magnetic field theory and SOLIDWORKS® and FEMM software packages, as well as analysis of the dependence of the damping properties of bushings from magnetorheological elastomers on magnetic flux density. A description of the design and principle of operation of the magnetorheological actuator of the vehicle suspension characteristics control system is given, based on which the calculation scheme was developed. Results. The results of research calculations showed that the average value of magnetic flux density in the proposed design of the device reached 0.85 T, its distribution became fairly uniform, and there were no zones where it was abnormally small. For the first time, the dependence of the damping index on the magnetic flux density of the controlling magnetic field has signs of scientific novelty. It was found that this indicator for the proposed design of the device increased by 22 % compared to previous other designs, which will increase the efficiency of the control system and the smoothness of the vehicle. A positive result was achieved due to the following features of the proposed design of the suspension actuator: the elastic sleeve consists of several coaxially located actuators made of anisotropic magnetorheological elastomer, in which the conglomerates of the ferromagnetic filler during the manufacturing process are located collinear to the direction of the angular deformations of the sleeve and the control magnetic field flux density vector, and the devices have control coils located on their surfaces, which are made of conductive elastic elastomer and electrically connected in a series circuit. Originality. The control method, previous designs and construction of this controlled suspension are protected by patents of Ukraine. Practical value. The direction of further research is to optimize the parameters of the control coils in order to reduce the energy consumption for them and to protect them from overheating. References 20, figures 10.

Nutrient is one of the conditions controlled in a plant factory. Nutrient control must be based on the plant growth phase, but previous research has shown shortcomings in this area. This study aims to develop a nutrient control system in a plant factory based on the plant growth phase, specifically using Romaine lettuce. The research method used is the experimental method, with research stages including system design (controller modification, programming, and TDS sensor calibration testing) and system performance testing. The TDS sensor calibration test results showed an R² of 0.9999, indicating that the TDS sensor readings are very close to those of the TDS meter. The system performance test results showed that the developed system works well in controlling nutrient levels based on the growth phase of Romaine lettuce. The planting process lasted 30 days, from October 13, 2023, to November 11, 2023, with a total of 2,697 data points recorded by Antares. Nutrient requirements were adjusted per the growth phase of Romaine lettuce, with set points in the first to fourth weeks being 500 PPM, 600 PPM, 700 PPM, and 800 PPM, respectively. The average nutrient levels recorded in the first week were 518 PPM, 623 PPM in the second week, 721 PPM in the third week, and 820 PPM in the fourth week. The TDS sensor accuracy test results showed an R² of 0.9998, indicating that the TDS sensor performed well in controlling nutrient levels during the system testing, with an average TDS sensor reading error of only 1.17%. During the planting process, the total amount of nutrients added for each of nutrients A and B was 210.10 ml, with the total operating time of the control components being 314.34 seconds for each peristaltic pump of nutrients A and B.

ObjectiveIn order to address the issues of inconvenience, high medical costs, and lack of universality associated with traditional knee rehabilitation equipment, a portable intelligent wheelchair for knee rehabilitation was designed in this study. MethodsBased on the analysis of the knee joint’s structure and rehabilitation mechanisms, an electric pushrod-driven rehabilitation institution was developed. A multi-functional module was designed with a modular approach, and the control of the wheelchair body and each functional module was implemented using an STM32 single-chip microcomputer. A three-dimensional model was established using SolidWorks software. In conjunction with Adams and Ansys simulation software, kinematic and static analyses were conducted on the knee joint rehabilitation institution and its core components. A prototype was constructed to verify the equipment’s actual performance. ResultsAccording to the prototype testing, the actual range of motion for the knee joint swing rod is 15.1°~88.9°, the angular speed of the swing rod ranges from −7.9 to 8.1°/s, the angular acceleration of the swing rod varies from −4.2 to 1.6°/s², the thrust range of the electric pushrod is −82.6 to 153.1 N, and the maximum displacement of the load pedal is approximately 1.7 mm, with the leg support exhibiting a maximum deformation of about 1.5 mm. ConclusionThe intelligent knee joint rehabilitation wheelchair meets the designed functions and its actual performance aligns with the design criteria, thus validating the rationality and feasibility of the structural design.

Photovoltaic panels are considered one of the important practical applications in converting solar energy into electrical energy, but they suffer from the effect of heat associated with solar radiation. Therefore, much research has been done to either harness the heat that comes with it or eliminate it by cooling the panel and boosting its effectiveness. In this work, a cooling box was designed and manufactured locally (the passage design is new) that is attached to the back wall as part of the panel without inserting an absorbent portion between it and the water to cool the panel. The new model was subjected to numerical and experimental tests to ascertain its efficacy in raising PV panel efficiency. ANSYS R19.2 software was used to compare numerical simulations with experimentally obtained results. The results showed good agreement between the two tests. The results also showed that the new model was able to raise the electrical efficiency of PV panels compared to the results of traditional panels without cooling, from 12.97% under the radiation intensity of 1035 W/m² to 14.87% under the same radiation intensity at a water flow rate of 4 L/min, this means an improvement of up to 12.78%. On the other hand, the control system reduced water consumption by 29.28% of the consumed water to maintain the efficiency ratio at semi-stable levels to its highest value of 15.37%, thus achieving an improvement of up to 15.56% for the same conditions above.

To address the current inefficiencies and subjective nature of manual observation in maize cultivation, with the aim of achieving high efficiency and productivity, this study focused on the DeMaya D3 maize variety. It proposes a maize growth stage recognition method based on the MobileNet model, which is a lightweight convolutional neural network architecture. The method was tested and achieved recognition accuracies of 0.98, 0.96, 0.92, 0.85, and 0.97 for different growth stages, respectively. Additionally, a maize growth prediction model was developed. Based on data collected from experimental plots regarding maize plant height and stem diameter, the Prophet model and an optimized version of the Prophet model were used to forecast maize growth trends. The Prophet model is an open-source tool for time series forecasting. Comparative analysis was conducted between the predictions of the original Prophet model and the optimized version. The relative errors of the Prophet model predictions were 0.85%, 2.11%, and 0.79%, while those of the optimized Prophet model were 0.76%, 0.47%, and 0.71%. Compared to the Prophet model, the optimized model reduced errors by 0.09%, 1.64%, and 0.08%, respectively. The maize plant growth control system was designed to obtain the information through the collection layer. The decision-making layer judged the soil nutrient absorption and growth status. Finally, the management layer controlled water and fertilizer.

The tendency to self-oscillations is one of the most important problems of closed-loop hydraulic systems. In actual systems losses occur, variation of the transmitted energy and the strength of the system structural elements are always limited. This is the reason why self-oscillations are most often present. The main purpose of the research is to reveal the mechanisms of instability and self-oscillations in an electro-hydraulic servo drive to make a numerical simulation of the drive characteristics. A servo drive has all the conditions for the generation of self-oscillations: the oscillatory element – the movable member of the drive and a column of elastic liquid, the source of energy. Regular oscillations in a drive are maintained due to the energy of compressed liquid, feedback, non-linear character of generated and absorbed energy etc. An experimental analysis of a servo system of the FESTO training simulator was carried out. The aim of the research was to accumulate materials for the development of mathematical models that would adequately represent the main properties of actual systems.

A physical mechanics simulation experiment is one of the important technical methods to study the inoculation mechanism and development laws of coal and gas outburst. A new type of coal and gas outburst simulation system has been developed, aiming at developing an advanced experimental design scheme with the help of existing advanced monitoring technology, combined with specific gas geology conditions, to realize the simulation of coal and gas outburst phenomenon in complex scenes, and to promote the study of coal and gas outburst mechanism. The physical mechanics simulation system consists of following seven parts: stress loading subsystem, test chamber subsystem, power traction subsystem, gas pressure control subsystem, induced equipment subsystem, simulated roadway subsystem, and measurement and control subsystem. The design of each subsystem has been improved to different degrees, and the whole system has formed a landmark innovation. The simulation system has the following characteristics: ① the high load loading and unloading function of the three-axis synchronous continuous non-uniform loading technical equipment is improved. The specimen loading is done by 10 independent indenters in X, Y, and Z directions. The size of the experimental chamber is 400 mm × 400 mm × 1200 mm, the maximum load strength is 25 MPa, and the maximum closed gas pressure is 6.0 MPa. Each of the above 10 indenters can operate asynchronously or synchronously for loading or unloading tasks according to instructions, and horizontal stress loading and unloading layered processing function is implemented. ② An integrated process of systematic sample preparation, sample packing, sealing, and loading has been formed completely. The experimental chamber is designed as a new type of split structure, and the dynamic traction system is used to assist the experimental chamber to complete the molding, stress loading and material handling, and the translation amount of the chamber structure is controlled accurately. ③ The four kinds of technologies for inducing coal and gas outburst are integrated and applied in the same simulation platform, and some equipment functional innovations are realized, such as the test chamber, the pressure relief window, etc. Many kinds of technology and equipment have been successfully developed, as original innovation products, the dynamic technology and the drilling equipment have been verified by the experimental simulation. ④ The design innovation of key device structure is realized. The problems of stress concentration and high pressure gas leakage under synchronous loading are solved by the design of double-layer steel plate chamber structure. The experimental efficiency is improved by the structural optimization of the launching cavity, the safety of the simulation system is significantly improved by the design of the pipe end structure, a combination of soft and hard material pipe structure, and the variable diameter drilling technology has achieved the engineering application of the Rouleauxs triangle theory. ⑤ Simulation test precision is generated by multivariate information. Advanced data acquisition systems (stress, gas pressure, temperature, etc.) and monitoring technology equipment including acoustic emission and high-speed cameras are used to achieve multi-data monitoring of coal and gas outburst. ⑥ The reliability of the experimental system has been verified by laboratory simulation. Through the case simulation of the “3·22 accident in Pingdingshan”, the overall test of the system function is completed, and the influence law of fault structure on in-situ stress, gas pressure and temperature in the process of coal and gas outburst is discovered in a new way. It is proved that the physical mechanics simulation system is reliable and could provide a platform to support the research on the coal and gas outburst mechanism.

The all-vanadium redox flow technology has garnered significant attention in the energy storage field, due to its attributes of high safety, high reliability, environmental friendliness, and power-capacity decoupling. Within all-vanadium redox flow energy storage setups, the control system is deemed the core, evolving towards enhanced integration, precision, and intelligence. This paper seeks to elevate these benchmarks and advance technological levels in the localization of this system. Based on a review of technologies related to the entire control system, this study conducted an in-depth analysis concerning key parameters and control logic. Addressing some key concerns within the control system, solutions were proposed, including temperature control, operational modes, and state-of-charge (SOC) estimation. The subsequent study focused on designing architecture for monitoring and managing all-vanadium redox flow energy storage systems through a modular approach, aiming at a more adaptable, elastic, and scalable control system. Furthermore, the developed control system was verified through practical implementation in commercial energy storage and applications under grid-connected environments. Based on the study outcomes, this paper also explores potential future technological trends for all-vanadium redox flow energy storage control systems in various aspects such as operation, maintenance, losses, and equilibrium.

Based on the complementary advantages of Line Commutated Converter (LCC) and Modular Multilevel Converter (MMC) in power grid applications, there are two types of hybrid DC system topologies: one is the parallel connection of LCC converter stations and MMC converter stations, and the other is the series connection of LCC and MMC converter stations within a single station. The hybrid DC transmission system faces broad application prospects and development potential in large-scale clean energy integration across regions and the construction of a new power system dominated by new energy sources in China. This paper first analyzes the system forms and topological characteristics of hybrid DC transmission, introducing the forms and topological characteristics of converter-level hybrid DC transmission systems and system-level hybrid DC transmission systems. Next, it analyzes the operating characteristics of LCC and MMC inverter-level hybrid DC transmission systems, provides insights into the transient stability of hybrid DC transmission systems, and typical fault ride-through control strategies. Finally, it summarizes the networking characteristics of the LCC-MMC series within the converter station hybrid DC transmission system, studies the transient characteristics and fault ride-through control strategies under different fault types for the LCC-MMC series in the receiving-end converter station, and investigates the transient characteristics and fault ride-through control strategies under different fault types for the LCC-MMC series in the sending-end converter station.

The paper describes the process of designing the cutting tool feed drive of a special metalworking machine, which due to the circuit solution and automatic control system will increase the productivity of processing one cell of wafer background on sheet material up to 10–15 seconds. On the basis of the analysis of the technology of milling of a given regular pattern of wafer background and peculiarities of the equipment operation it proposed to replace the traditional ball bearing gear in the cutting tool feed drive with a flat combined crank-slide mechanism. Geometrical parameters of the lever transmission mechanism calculated in accordance with the known dimensions of the regular cell pattern and the recommended value of the angle of motion transmission. The analysis of kinematic and power characteristics of the lever mechanism allowed to justify the technical characteristics of the electric motor. In order to realize the required trapezoidal law of the output link speed change, the inverse problem of kinematics solved, numerical values of the instantaneous angular velocity of the input crank and pulse control signals to the servomotor obtained.

This article presents an innovative approach for developing the mechanical and control systems of humanoid 3D-printed hand with fingers, based on a modular principle. The novelty is in creating the 3D printed fingers as a single assembled component and embedding the actuators and control elements, thus making it a complete independent module. The new approach allows the implementation of the same software and actuating components to be used in finger modules with different individual sizes and joint constraints. The mechanical and control system of the hand is developed and a working prototype is created. It is described how to adjust and control the position of fingers with different sizes and joint constraints. The communication of the modules with the developed software is described. The repeatability of finger movement is studied and the force that each finger is capable of exerting during folding is measured. Functional experiments are performed and discussed.

In view of the problems existing in the water spray automatic fire extinguishing control system of 500kV transformer, the overall solution of the control system is proposed from the perspective of the independence, reliability and overall monitoring of the system to ensure the safe and reliable operation of fire fighting in 500kV substation. First of all, this paper optimizes the equipment configuration and control loop of the main control system of water spray, and details the design of the various boxes and cabinets in the system; secondly, five starting design schemes of transformer fire pump are put forward; Finally, design schemes can be proposed for auxiliary circuits such as anti-interference measures and signal monitoring of the control system. [ABSTRACT FROM AUTHOR]

The aeroengine control system is a safety critical system for aeroengine, crucial for generating reliable thrust or power within the entire flight envelope of the engine. This paper presents the evolution of the aeroengine control system, summarizes and analyzes the development of three key system-level technologies. including architecture design, control law design, and fault diagnosis and condition monitoring design, as well as simulation enabling technologies. The discussion on the applicability of these technologies in engineering is then conducted. The prospects for future development directions and key research areas are finally explored, providing a valuable reference for the design of next generation aeroengine control systems. [ABSTRACT FROM AUTHOR]

In order to improve the intelligent perception and adaptability of the 6G network, drones joined this challenge. For large-scale long-range Unmanned Aerial Vehicle (UAV), most of the time during normal flight belongs to fixed altitude flight. It is required to sail along the planned optimal path. Whether it can fly along the optimal path is mainly attributed to the tracking problem of horizontal flight trajectory. In order to minimize the UAV horizontal plane tracking error, it is necessary to consider the influence of many factors (such as strong winds, heavy rain, obstacles, etc.). Due to the complexity of High-Altitude environment, these disturbances are uncertain. In addition, there are some dynamic errors in the model of UAV control system, and these errors also have uncertainties. And, due to the change of global planning path coordinates, the control system needs to adjust the set value in real time during AUV horizontal trajectory tracking, and the conventional control algorithm is difficult to meet the requirements. Therefore, firstly, the influence of prediction uncertainty of grey prediction on AUV horizontal track tracking control is used; Then the grey prediction is improved according to the practical application; Ultimately, the control law is designed by combining the grey prediction with the control method. Finally, the grey prediction fuzzy adaptive PID method of UAV flight control is applied to the planned path simulation, and good control results are obtained. [ABSTRACT FROM AUTHOR]

For improving the energy efficacy and control performance, integration of swarm optimization with controller design could successfully reach this objective. In this study, a comparative analysis has been conducted between two decentralized control structures based on optimized Proportional-Integral-Derivative (PID) and PID-Proportional (PID-P) controllers for optimal controlling of heating system in multi-zone building. Based on the energy balance equation, the mathematical dynamics model of the heating system is established in the building. In order to enhance and optimize the performances of both controllers, their design parameters are tuned based on Whale Optimization Algorithm (WOA). Two objectives have been considered in the optimization process of heating system. The first objective is to minimize the error in temperature, between the desired and real temperatures, based on IAE (Integral of Absolute Error) index, while the second objective is the minimization of the heat energy consumption. The normalization method has been used to adjust between the two differently-scaled objectives. Simulation results based on MATLAB reveal that the PID-P controller achieved better performance in terms of providing comfort indoor temperature with energy savings as compared to the PID controller. [ABSTRACT FROM AUTHOR]

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Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper an approximation of the set of multivariable and $ L_2 $ integrable trajectories of the control system described by Urysohn type integral equation is considered. It is assumed that the system is affine with respect to the control vector. The admissible control functions are chosen from the closed ball of the space $ L_2 $, centered at the origin with radius $ \rho $. The set of admissible control functions is replaced, step by step, by the set of controls consisting of a finite number of piecewise-constant control functions. It is proved that under appropriate choosing of the discretization parameters, the set of trajectories generated by a finite number of piecewise-constant control functions is an internal approximation of the set of trajectories. [ABSTRACT FROM AUTHOR]

The tasks of forecasting a possible scenario of unintentional destructive impacts (mass impacts like voltage fluctuations, industrial electromagnetic interference, natural impacts) on a distributed automated control system are discussed. Analytical relationships are proposed to assess the consequences of such destructive impacts (signal transmission systems, communication systems). One of the possible scenarios of such impacts on the system is considered, taking into account the distribution of the intensity. [ABSTRACT FROM AUTHOR]