Operation Principle Research Articles

APPLICATION OF MACHINE LEARNING TECHNIQUES TO INCREASE THE LEVEL OF ACCURACY OF OPTICAL CHARACTER RECOGNITION RESULTS

One of the most pervasive processes of modernity is undoubtedly digitalization, which has encompassed all key spheres of human life. The development of information technology has contributed to large-scale changes not only in the everyday aspect of life, but also more globally, automating complex business processes in the field of entrepreneurship, economics, and healthcare. The transition to digital data and documentation has provided greater accessibility to necessary information and has also enhanced the efficiency of its analysis and processing. Due to this fact, optical character recognition (OCR) technology has gained significant importance, enabling the identification and extraction of textual data from images. OCR systems play a pivotal role in the digital transformation of society as they eliminate the need for manual handling of textual information in images and are applicable in automating the majority of business processes associated with paper-based data processing, such as gathering statistical data from paper forms, reflecting paper documents in electronic document management systems, converting textual information into audio files, and so on. This paper is dedicated to describing optical character recognition technology, as well as providing an overview of machine learning techniques that are actively used in the context of its modern implementation, in order to enhance the quality of the obtained results. In addition, the paper presents the principles of operation of the described approaches, their capabilities, as well as some limitations that may be encountered when using them in various scenarios.

Research on the distribution structure of 2D piston electro-hydraulic pump based on fluid-structure interaction

To address the drawbacks of traditional hydraulic power units, we embedded a 2D piston pump inside the motor rotor, proposing a 2D piston electro-hydraulic pump. The space cam mechanism serves as the primary force-bearing structure during its operation. Excessive wear occurs at the highest point of the space cam when subjected to significant axial forces, which leads to deviations between the motion law of the 2D piston and the theoretical design. Aiming this problem, we conduct research from two perspectives: theoretical analysis and fluid-structure interaction. Firstly, the operational principle of the electro-hydraulic pump is introduced. Then, the contact normal stress of the space cam mechanism is studied, and backflow and chamber pressure overshooting are discussed. Finally, the fluid-structure interaction model of the electro-hydraulic pump is established. Based on the fluid-structure interaction model, the effects of the width and depth angles of the triangular damping groove on the backflow and chamber pressure overshooting are analyzed. The simulation results demonstrate that adding triangular damping grooves can improve the flow field characteristics. With the increase in the width and depth angles, the peak flow of the backflow and chamber pressure overshooting increase, with the depth angle exerting a more pronounced effect.

Fault isolation considering real mechanical coupling effects with application to liquid oxygen/kerosene staged combustion rocket engines

Liquid rocket engines are crucial for space exploration, necessitating reliable fault diagnosis systems. This paper focuses on fault isolation in liquid oxygen (LOX)/kerosene staged combustion rocket engines. Addressing deficiencies in current methods, we first propose a theorem to evaluate the adaptability between the analytical model and fault factors based on available sensors. Through the analysis of fault mechanisms, this paper defines fault modes using an innovative multi-factor coupling approach based on engine operational principles. Moreover, a fault isolation method with two steps is established, incorporating the optimal selection of sensors to accommodate robust requirements. This method features a clear process, low computational complexity, and comprehensive fault coverage, and it can also be applied to systems with similar complex operational mechanisms.

A soft switching non‐isolated bidirectional DC–DC converter with improved voltage conversion ratio and minimum number of switches

AbstractA soft switching non‐isolated bidirectional DC–DC converter with an improved voltage conversion ratio without any additional auxiliary switch is presented in this paper. In the proposed converter, improved step‐up/step‐down gain conversion is achieved by employing the coupled inductors method. Also, the auxiliary circuit provides soft switching conditions for all the semiconductor elements, regardless of the power flow direction and without any extra voltage stress. The other switch helps provide soft switching conditions for the main switch. Moreover, the switch used for providing soft switching conditions operates as a synchronous rectifier as well. The additional circuit added to attain soft switching is composed of an inductor, coupled with the converter's main inductor, and two auxiliary diodes. The auxiliary diodes benefit from zero‐current‐switching conditions. Fully soft switching conditions for all semiconductor devices, removing the reverse recovery problem, and a low number of components have led to mitigating switching losses and improving efficiency. Detailed operating principles and a theoretical analysis of the proposed converter are presented. Also, the experimental results of a 220 W prototype circuit are provided to confirm the validity of the proposed topology.

Optimal operation strategy for renewable power plants based on 5G base stations response

Abstract The integration of large-scale new energy sources has led to a significant challenge in electricity supply and demand balancing within the power system. To address this issue, it is crucial to establish an optimization strategy of renewable power plant based on 5G base stations response. Firstly, according to the operating state of the base station, the energy storage schedulable strategy of the base station was designed. Then, through the regulation function of the base station’s reserve energy storage and the operation principle of the renewable energy power plant, the operation model of the renewable power plant considering the base station’s participation and response was established. Finally, evaluation indexes such as the absolute peak-to-valley difference, the standard deviation of daily load and the peak-valley difference rate can be used to measure system optimization results. The results show that the proposed strategy improves the source load imbalance in the power system while enhancing reliability and economy of new energy.

Quasi‐Z‐source interleaved DC‐DC converter for fuel cell vehicle application

AbstractIn this study, a step‐up DC‐DC converter with a combination of a two‐phase interleaved structure and a quasi‐Z impedance network is proposed for fuel cell vehicle application. The operation of the converter in a small duty cycle (0 < D < 0.5) reduces the conductive losses of the switches and as a result increases the efficiency of this converter compared to conventional boost converters. Also, due to the common ground between the input and output, unlike the floating interleaved boost converter (FIBC) and the parallel input‐series output converter (PISO), it does not face the problem of imposing additional EMI on the converter circuit. This converter has a low input current ripple, suitable voltage gain for fuel cell vehicles system, as well as high reliability due to the ability to operate with one phase in case of failure in the other phase. It can be a suitable candidate for practical application in fuel cell vehicles. The principles of operation and the main characteristics of the converter such as voltage gain, input current ripple, and voltage and current stress of the elements are explained and also a 120‐W experimental prototype with 12‐V input voltage and 60‐V output voltage is made to validate the theoretical analysis results.

MEMS Micromirror Actuation Techniques: A Comprehensive Review of Trends, Innovations, and Future Prospects

Micromirrors have recently emerged as an essential component in optical scanning technology, attracting considerable attention from researchers. Their compact size and versatile capabilities, such as light steering, modulation, and switching, are leading them as potential alternatives to traditional bulky galvanometer scanners. The actuation of these mirrors is critical in determining their performance, as it contributes to factors such as response time, scanning angle, and power consumption. This article aims to provide a thorough exploration of the actuation techniques used to drive micromirrors, describing the fundamental operating principles. The four primary actuation modalities—electrostatic, electrothermal, electromagnetic, and piezoelectric—are thoroughly investigated. Each type of actuator’s operational principles, key advantages, and their limitations are discussed. Additionally, the discussion extends to hybrid micromirror designs that combine two types of actuation in a single device. A total of 208 closely related papers indexed in Web of Science were reviewed. The findings indicate ongoing advancements in the field, particularly in terms of size, controllability, and field of view, making micromirrors ideal candidates for applications in medical imaging, display projections, and optical communication. With a comprehensive overview of micromirror actuation strategies, this manuscript serves as a compelling resource for researchers and engineers aiming to utilize the appropriate type of micromirror in the field of optical scanning technology.

Legality - Theory and Practice

Legality is a multifaceted, complex legal phenomenon. This phenomenon is central to legal theory and can be considered from many different aspects: political - ideological, economic - social, ethical, and legal. Law is the method of organizing and exercising state power, the principles of organization and operation of agencies, organizations, officials, civil servants, and the behavior of individuals. Today, under the impact of the market economy, misconducts, corruption, and legal violations tend to increase, so it is necessary to apply synchronous solutions to strengthen the legality

PROSPECTS FOR THE USE OF COMBINED METAL-CUTTING TOOLS FOR THREADING

This article examines the use of combined metal-cutting tools for performing threading operations. The main purpose of the work is to analyze the effectiveness of using these tools in terms of improving accuracy, productivity and cost-effectiveness of processing. Combined tools show significant advantages over traditional methods, including reduced processing time, improved accuracy characteristics and reduced equipment maintenance costs. The design features and principles of operation of boring threaded cutters and threaded combs, as well as their impact on production processes and the quality of final products, are considered. Threading with the use of combined metal cutting tools allows you to integrate several technological operations in one cycle, which helps to increase efficiency and reduce basing errors. Experimental data confirm that the use of comb cutters contributes to a significant increase in processing accuracy and productivity, as well as reducing the time required to perform operations. Comparative analysis has shown that combined tools provide a higher quality of the thread being cut and an extended service life compared to traditional processing methods. Keywords: combined metalcutting tools, threading tools, boring threaded cutters, threaded combs, threading, productivity, processing quality.

APPLICATION OF INNOVATIVE TECHNOLOGIES IN THE FIELD OF WASTEWATER TREATMENT: FOREIGN AND KAZAKHSTANI EXPERIENCE

The article discusses modern innovative technologies used in the field of wastewater treatment. Special attention is paid to the principles of operation, advantages and applications of technologies such as membrane bioreactors, anaerobic reactors, aerobic granular precipitation, photocatalytic and electrochemical purification, as well as bio- and nanofiltration. The analysis of the experience of the implementation of these technologies in various countries, including successful cases demonstrating the improvement of the quality of water resources and increasing the efficiency of water treatment systems. The experience of Kazakhstan is considered separately, where the use of advanced wastewater treatment methods is becoming an important element of environmental safety. A comparative analysis of the effectiveness of the use of technologies in Kazakhstan and abroad is carried out, the main factors influencing the success of their implementation in the country are highlighted.

Evaluation of Lithium-ion Batteries in Electric Vehicles

Growing awareness of climate change concerns and the environmental impacts of fossil fuel vehicles has heightened interest in electric vehicles (EVs). Therefore, EVs represent a significant component of sustainable transportation solutions. Additionally, with advancements in battery technology, EVs now have longer ranges and are offered at more competitive prices. With their notable features such as high energy density, lightness, low maintenance requirement, and long life, lithium-ion batteries (LiBs) appear to be the most suitable battery option for EVs. Nevertheless, current LiB technology faces battery costs, energy storage capacity, charging times, and safety issues. In this context, it is clear that future research and development will focus on improving the efficiency of LiB technology and making these batteries more sustainable, reliable, and economical. This study aims to provide an evaluation of the LiBs used in the automotive sector by examining the historical development, basics of operational principles, various geometric types, cost evaluation, and their advantages and disadvantages. By covering these aspects, the study seeks to offer a comprehensive assessment of the LiBs employed in the automotive industry, spanning from their historical evolution to their presentday utilization. The study also intends to serve as a reference source for researchers planning to conduct studies on LiBs in EVs by providing fundamental concepts and evaluations related to these batteries.

Geometric Landscape Annealing as an Optimization Principle Underlying the Coherent Ising Machine

Given the fundamental importance of combinatorial optimization across many diverse domains, there has been widespread interest in the development of unconventional physical computing architectures that can deliver better solutions with lower resource costs. However, a theoretical understanding of their performance remains elusive. We develop such understanding for the case of the coherent Ising machine (CIM), a network of optical parametric oscillators that can be applied to any quadratic unconstrained binary optimization problem. We focus on how the CIM finds low-energy solutions of the Sherrington-Kirkpatrick spin glass. As the laser gain of this system is annealed, the CIM interpolates between gradient descent on coupled soft spins to descent on coupled binary spins. By combining the Kac-Rice formula, the replica method, and supersymmetry breaking, we develop a detailed understanding of the evolving geometry of the high-dimensional energy landscape of the CIM as the laser gain increases, finding several phase transitions in the landscape, from flat to rough to rigid. Additionally, we develop a novel cavity method that provides a geometric interpretation of supersymmetry breaking in terms of the reactivity of a rough landscape to specific external perturbations. Our energy landscape theory successfully matches numerical experiments, provides geometric insights into the principles of CIM operation, and yields optimal annealing schedules. Published by the American Physical Society 2024

TO THE ISSUE OF NON-PROJECT FUEL COMBUSTION

Nowadays, the issues of ecology and sustainable development are becoming more and more urgent, and the scientific community is actively looking for ways to more efficient and environmentally friendly use of renewable energy sources. One of such directions is the development and improvement of coal combustion technologies in aerodynamic furnaces. This paper offers a detailed analysis of this topic, looking at both theoretical aspects and practical applications. Aerodynamic furnaces are specialised devices designed to burn solid fuels such as coal with maximum efficiency and minimum environmental impact. The basic principle of operation of such furnaces is to create optimum conditions for complete combustion of the fuel, which is achieved through carefully designed aerodynamics and process control. The operation of the boiler on the coal of Karazhyra deposit is considered. This coal belongs to non-project fuel and improvement of its combustion processes is required to reduce harmful emissions and increase combustion efficiency. For the energy sector of the Republic of Kazakhstan, the conducted research is important, and the results obtained can be used to regulate and improve the operation of similar equipment, which contributes to improving environmental performance and overall efficiency of the country's energy systems.

Collaborative optimization of electric-vehicle battery swapping stations based on energy storage sharing

Due to the extensive integration of distributed renewable energy resources, the Active Distribution Network (ADN) faces numerous challenges, including, for example, renewable energy curtailment and overloading. This paper proposes a collaborative optimization control method for electric-vehicle battery swapping stations that mitigates the mismatching between generation and load demand in the ADN. Energy storage sharing is considered in this study, that allows stations to exchange batteries via the traffic network, and this extends the capacity of Battery-Transferable Swapping Stations (BTSSs). First, the operational principles of the energy storage shared BTSS are carefully analyzed, including external and internal control mechanisms and energy storage sharing. Subsequently, a bi-level optimization model is proposed, whereby the upper level aims to minimize the total operational cost of the ADN and the lower level seeks to maximize the benefit of each BTSS. A two-stage transactive control is introduced to decompose the bi-level situation into two stages: the day-ahead stage and the real-time stage and this facilitates easier problem-solving. Finally, an IEEE 15-node system is utilized to verify the proposed method. The results indicate that the proposed method reduces the renewable energy curtailment, power shortages, and operational costs of the ADN, while at the same time increasing the earnings of BTSSs.

Advances in microbial whole-cell sensors for the detection of aromatic compounds

The inherent stability and recalcitrance of benzene ring structures render aromatic compounds a major ecological concern and a substantial risk to human health. Hence, developing a facile and efficacious detection technique for aromatic compounds is essential. As our comprehension of aromatic compound characteristics deepens, microbial cell-based biosensors have emerged as increasingly popular tools in the detection of aromatic compounds. This article introduces the operational principles of microbial whole-cell biosensors and elucidates the construction techniques and applications of electroactive biofilm-based microbial whole-cell sensors, transcription factor-based microbial whole-cell sensors, and degradation gene promoter-dependent microbial whole-cell sensors in the detection of aromatic compounds. In addition, we review the methodologies for improving the performance of microbial whole-cell sensors based on surface display, logic gate construction, genetic circuit modification, and quorum sensing signal amplification.

Is there a ubiquitous spectrolaminar motif of local field potential power across primate neocortex?

Mendoza-Halliday, Major et al., 2024 ("The Paper")1 advocates a local field potential (LFP)-based approach to functional identification of cortical layers during "laminar" (simultaneous recordings from all cortical layers) multielectrode recordings in nonhuman primates (NHPs). The Paper describes a "ubiquitous spectrolaminar motif" in the primate neocortex: 1) 75-150 Hz power peaks in the supragranular layers, 2) 10-19 Hz power peaks in the infragranular layers and 3) the crossing point of their laminar power gradients identifies Layer 4 (L4). Identification of L4 is critical in general, but especially for The Paper as the "motif" discovery is couched within a framework whose central hypothesis is that gamma activity originates in the supragranular layers and reflects feedforward activity, while alpha-beta activity originates in the infragranular layers and reflects feedback activity. In an impressive scientific effort, The Paper analyzed laminar data from 14 cortical areas in 2 prior macaque studies and compared them to marmoset, mouse, and human data to further bolster the canonical nature of the motif. Identification of such canonical principles of brain operation is clearly a topic of broad scientific interest. Similarly, a reliable online method for L4 identification would be of broad scientific value for the rapidly increasing use of laminar recordings using numerous evolving technologies. Despite The Paper's strengths, and its potential for scientific impact, a series of concerns that are fundamental to the analysis and interpretation of laminar activity profile data in general, and local field potential (LFP) signals in particular, led us to question its conclusions. We thus evaluated the generality of The Paper's methods and findings using new sets of data comprised of stimulus-evoked laminar response profiles from primary and higher-order auditory cortices (A1 and belt cortex), and primary visual cortex (V1). The rationale for using these areas as a test bed for new methods is that their laminar anatomy and physiology have already been extensively characterized by prior studies, and there is general agreement across laboratories on key matters like L4 identification. Our analyses indicate that The Paper's findings do not generalize well to any of these cortical areas. In particular, we find The Paper's methods for L4 identification to be unreliable. Moreover, both methodological and statistical concerns, outlined below and in the supplement, question the stated prevalence of the motif in The Paper's published dataset. After summarizing our findings and related broader concerns, we briefly critique the evidence from biophysical modeling studies cited to support The Paper's conclusions. While our findings are at odds with the proposition of a ubiquitous spectrolaminar motif in the primate neocortex, The Paper already has, and will continue to spark debate and further experimentation. Hopefully this countervailing presentation will lead to robust collegial efforts to define optimal strategies for applying laminar recording methods in future studies.

The Study of the Process of Supplying Seeds of Row Crops Using a Vacuum Seed-Placing Unit

Introduction. The performance of precision seeders depends on many factors, including the functionality of their dosing systems, the modernization of which is possible only on the basis of patterns, which allows forecasting the indicators of single seed placing into a furrow.Aim of the Study. The study is aimed at analyzing the influence of the diameter of the suction holes of seed-placing units and the rarefaction created in them on the characteristics of placing seeds of the main row crops.Materials and Methods. The results of the study were obtained based on a series of experiments on sowing corn and sunflower seeds using an MS-8 seeder, the operation principle of which can be considered typical for vacuum seed-placing units.Results. There have been obtained empirical dependences of the particular features of zero and group placing seeds of such row crops as corn and sunflower on the area of the suction holes and the rarefaction in the vacuum chamber.Discussion and Conclusion. The quantitative estimates obtained may differ for seeds of the same crop, but having different technological properties. The general factor is that the frequency of missing seeds is proportional to the suction force magnitude in the working plane of the metering element, regardless of its area. At the same time, the probability of double seed placing depends on the area of the metering ports with a constant suction force, a decrease in their diameter leads to a decrease in the frequency of double seed placing. The data obtained allow considering joint variations in the magnitude of the rarefaction in the vacuum chamber and the diameter of the suction holes as effective tools for improving the seed placing quality.

A Flyback Converter with a Simple Passive Circuit for Improving Power Efficiency

This paper proposes an effective method to improve the power efficiency of the flyback converter in the continuous conduction mode (CCM). The proposed converter uses a simple passive circuit to reduce the switching power losses. The current through the output diode can be shifted to a new branch where one diode, one inductor, and one auxiliary winding of the transformer are included. The output diode current can be reduced to zero for the zero-current switching of the output diode. The additional inductor is used to control the changing rate of the additional diode current to reduce the reverse-recovery current. Keeping the simplicity of the passive method, the proposed converter improves the power efficiency compared to the conventional converter. The circuit configuration and the operation principle are described. The design considerations are presented, including the simulation verification. The experimental results for a 45 W prototype are discussed to evaluate the performance of the proposed converter. The proposed converter has achieved a power efficiency of 93.5% for the rated load condition, improving the power efficiency. The applications of the proposed converter are also discussed for the future research directions.

Comprehensive review on evolution, progression, design, and exploration of electric bicycle

Many countries are moving to electric vehicles for daily transportation due to the scarcity of fossil fuels and the pollution emissions from internal combustion engines. The most promising technique to manage environmental pollution and energy security is the employment of electric vehicles. The electric bicycle is gaining an abundance of attention due to the various advantages of electric vehicles. Recently, people started using electric bicycles on a regular basis, and it is a suitable option for shorter daily rides. The present study was conducted using the Scopus database, which included an analysis of all papers pertaining to the content of electric bicycles up until the year 2023.The literature review delves into the profound impact and numerous benefits of electric bicycles, highlighting their potential for revolutionizing transportation. This exploration is informed by advancements in design and construction, offering insights into optimal electric bicycle development. One promising avenue for sustainability involves integrating solar technology into these vehicles, reducing reliance on conventional energy sources, and addressing environmental concerns. Discussions encompassed diverse aspects, including operation principles, throttle variations, commutation systems, self-charging mechanisms, health advantages, and solar-powered electric bicycles. To address this, the goal is to create universally acceptable electric bicycles to broaden their appeal and dispel misconceptions. In order to provide scientists and researchers with beneficial information to further optimize electric bicycles, the research fields pertaining to electric bicycles are reviewed in accordance with previous studies.

Development of a pilot plant for improvement water purification technologies at Desnianska water treatment plant in Kyiv

Providing the population with high-quality drinking water is one of the priority tasks of modern society. In Ukraine, which is experiencing challenges related to the need to modernize critical infrastructure, this task is of particular relevance. The Desnianska Water Supply Station (DVS), which supplies drinking water to a large part of Kyiv, needs a comprehensive renovation due to the deterioration of water quality at the water supply source and outdated treatment technologies. In this context, pilot studies are an important tool for optimizing and selecting effective technological solutions before their implementation on an industrial scale. The article discusses the development of a pilot plant to improve the technology of water purification at the Desnianska water supply station in Kyiv. The main goal of the study is to increase the efficiency of the water purification process through the introduction of the latest technologies and methods. The paper describes 4 technological schemes of water purification and the principle of operation of the pilot plant, as well as the justification for the use of such technological schemes. Requirements for research include: working out technological schemes during all seasons of the year; laboratory control of water quality at all stages of purification and disinfection; preparation of interim and final reports; presentation of research results. After the research, a significant improvement in the quality of treated water and a reduction in operating costs are expected. The proposed recommendations can be used to modernize existing water supply stations and introduce new technologies in the field of water supply.