Simulation of Electro-Hydraulic Systems Taking Into Account Typical Faults

2020 ◽  
Author(s):  
Albert Gareev ◽  
Asgat Gimadiev ◽  
Ilya Popelnyuk ◽  
Dmitry Stadnik ◽  
Viktor Sverbilov
Keyword(s):  
Experimental Studies ◽  
Simulation Models ◽  
Residual Service Life ◽  
Hydraulic Systems ◽  
Diagnostic Features ◽  
Accurate Identification ◽  
Flow Displacement ◽  
Diagnostic Signs ◽  
Diagnostic Complex ◽  
The Impact

Abstract In order to increase efficiency of diagnostics of electro-hydro-mechanical systems (EHMS) it is advisable to have simulation models of typical faults. Such approach makes it possible to estimate in advance, even at the stage of mathematical modeling, the impact of different faults on functioning of hydraulic systems. This work is aimed at creating a database containing complexes of diagnostic features, which allow distinguishing types of faults, their causes and stages of development. In the paper, typical faults of EHMS are presented on the basis of statistical information from literature sources and experimental research. They include internal and external leakages, spool and sleeve sticking, degradation of power fluid. The causes of faults and their impact on hydraulic systems functioning are considered. Simulation models of typical faults are implemented and studied in the SimulationX software package. The static and dynamic characteristics of the systems are investigated in order to identify diagnostic signs of various faults. The impact of typical faults on various system parameters is discussed. During the research, the tasks of selecting the rational location of sensors of different types (pressure, flow, displacement, or force sensors), their quantity for recognition of a typical fault are solved. The results of theoretical and experimental studies of serviceable and faulty systems for cases of control and disturbance actions are presented. Comparative analysis of transient processes of serviceable and faulty EHMS is presented with assessment of difference between theoretical and experimental data. The results of the work allow to more rationally designing the diagnostic complex for more accurate identification of the type of fault, stage of its development and prediction of residual service life of EHMS.

scholarly journals Imitation models of aircraft hydraulic units with account for typical faults

2019 ◽  
Vol 18 (1) ◽  
pp. 30-41
Author(s):  
A. M. Gareyev ◽  
I. A. Popelnyuk ◽  
D. M. Stadnik
Keyword(s):  
Hydraulic System ◽  
Quantitative Estimation ◽  
Simulation Models ◽  
Statistical Information ◽  
Hydraulic Systems ◽  
Operational Parameters ◽  
Accurate Localization ◽  
Literary Sources ◽  
Reference Curves ◽  
The Impact

А method based on comparing oscilloscope patterns of operational parameters with reference curves is one of the most promising methods of diagnosing hydraulic systems among the existing ones. Its implementation does not allow accurate localization of the faulty unit in the system and quantitative estimation of the magnitude of the fault. To eliminate these shortcomings, it is advisable to use simulation models of hydraulic units, taking into account typical faults of a hydraulic system. Their use makes it possible to evaluate the effect of a particular malfunction on the change of dynamic parameters at the stage of mathematical modeling. As a result of the analysis of statistical information and literary sources, characteristic faults of hydraulic systems are identified. Their causes and the impact on the operation of hydraulic units are examined. Simulation models of units taking into account typical faults are described in the Matlab / Simscape software package. They are implemented using a typical hydraulic system as an example. Dynamic characteristics of a hydraulic system in a healthy condition and those of a system with one of the characteristic faults are compared.

scholarly journals EXPERIMENTAL RESEARCH AND MODELING OF DEFECTIVE STATES OF MECHATRONIC SYSTEMS WITH MECHANISMS OF CYCLIC ACTION

2021 ◽  
Vol 160 ◽  
pp. 3-12
Keyword(s):  
Mathematical Modeling ◽  
Experimental Research ◽  
Cycle Time ◽  
Experimental Studies ◽  
Rotary Table ◽  
Hydraulic Systems ◽  
Mechatronic Systems ◽  
Cyclic Action ◽  
Diagnostic Signs

The results of experimental studies and mathematical modeling of the processes of the appearance of defective states of turntable mechanisms are presented. The main criteria for the operational state of the mechanisms, including the cycle time and the value of the error of angular division, are identified. The complex of diagnostic signs for recognition of defects of mechanical and hydraulic systems of rotary table is offered.

scholarly journals Analysis of the influence of design parameters on the agro-ecological qualities of tractor tires

2021 ◽  
Vol 937 (3) ◽  
pp. 032010
Author(s):  
V Kravchenko ◽  
L Kravchenko ◽  
V Oberemok ◽  
A Avanesyan
Keyword(s):  
Experimental Studies ◽  
Simulation Models ◽  
Contact Spot ◽  
Design Parameters ◽  
Physical Processes ◽  
Software Environment ◽  
Ground System ◽  
Mobile Machinery ◽  
The Impact ◽  
Normal Deflection

Abstract Experimental studies of the impact of agricultural mobile machinery movers on the soil are seasonal in nature and require complex experimental equipment. The complexity of the physical processes occurring in the elastic wheel-ground system requires the introduction of many assumptions and limitations that reduce the accuracy of the results, according to the design of simulation models performed in the software environment. The aim of the research was to study the influence of the design parameters of the tire on the efficiency of the normal deflection along the contact spot zone X. Studies have shown that 65% to 77% of the normal deflection of the tire is used when passing the contact spot. The reinforcement parameters of the tire frame have the greatest impact on the efficiency of the normal deflection along the contact spot zone. With an increase in the number of layers of the frame cord from 2 to 8, the coefficient of usability of the normal deviation for the stroke of the contact spot decreases from 0.761 to 0.689, with an increase in the angle of inclination of the frame cords - decreases from 0.755 to 0.693.

scholarly journals The assessment of the impact of the chosen exploational conditions of hydraulic arrangement on the working liquid condition

2018 ◽  
Vol 182 ◽  
pp. 01026 ◽  
Author(s):  
Joanna Wilczarska ◽  
Ewa Kuliś ◽  
Marcin Łukasiewicz ◽  
Łukasz Fornal ◽  
Natalia Dluhunovych
Keyword(s):  
High Efficiency ◽  
Experimental Studies ◽  
Working Fluid ◽  
Hydraulic Systems ◽  
Research Activities ◽  
Filtration System ◽  
Analysis Of Results ◽  
Liquid Condition ◽  
The Impact ◽  
Working Liquid

Hydraulic systems in modern vehicles and agricultural machines have many components. In order to achieve high efficiency of the system, the system requires an accurate filtration system that allows you to reduce the amount of contaminants. Therefore, an important aspect is to determine the content of impurities in the working liquid, so we can diagnose and then predict the durability of the entire hydraulic system. This paper presents selected methods and means of state assessment, as well as the methodology for testing the working fluid. The results of experimental studies conducted in accordance with the developed methodology have been presented, which made it possible to obtain an appropriate analysis of results and draw appropriate conclusions. The results of the research confirmed the validity of the research activities undertaken using the passive experiment.

Воздействиеультразвуковогополянадинамическуювязкостьводы

2019 ◽  
pp. 27-29
Author(s):  
P. Vikulin ◽  
K. Khlopov ◽  
M. Cherkashin
Keyword(s):  
Dynamic Viscosity ◽  
Experimental Studies ◽  
Ultrasonic Field ◽  
Maximum Effect ◽  
Ultrasonic Frequency ◽  
Ultrasonic Vibrations ◽  
Wastewater Disposal ◽  
Laboratory Setup ◽  
Sonic Treatment ◽  
The Impact

Enhancing water purification processes is provided by various methods including physical ones, in particular, exposure to ultrasonic vibrations. The change in the dynamic viscosity of water affects the rate of deposition of particles in the aquatic environment which can be used in natural and wastewater treatment. At the Department Water Supply and Wastewater Disposal of the National Research Moscow State University of Civil Engineering experimental studies were conducted under laboratory conditions to study the effect of ultrasound on the change in the dynamic viscosity of water. A laboratory setup has been designed consisting of an ultrasonic frequency generator of the relative intensity, a transducer (concentrator) that transmits ultrasonic vibrations to the source water, and sonic treatment tanks. Experimental studies on the impact of the ultrasonic field in the cavitation mode on the dynamic viscosity of the aqueous medium were carried out the exposure time was obtained to achieve the maximum effect.Интенсификация процессов очистки воды осуществляется с помощью различных методов, в том числе и физических, в частности воздействием ультразвуковых колебаний. Изменение динамической вязкости воды влияет на скорость осаждения частиц в водной среде, что может быть использовано в процессах очистки природных и сточных вод. На кафедре Водоснабжение и водоотведение Национального исследовательского Московского государственного строительного университета в лабораторных условиях проведены экспериментальные исследования по изучению влияния ультразвука на изменение динамической вязкости воды. Разработана схема лабораторной установки, состоящая из генератора ультразвуковых частот с соответствующей интенсивностью, преобразователя (концентратора), передающего ультразвуковые колебания в исходную воду, и емкости для озвучивания. Выполнены экспериментальные исследования по влиянию ультразвукового поля в режиме кавитации на динамическую вязкость водной среды, получено время экспозиции для достижения максимального эффекта.

Family Influences on Youth Offending

2018 ◽  
pp. 377-403
Author(s):  
Abigail A. Fagan ◽  
Kristen M. Benedini
Keyword(s):  
Life Course ◽  
Family Environment ◽  
Parenting Practices ◽  
Experimental Studies ◽  
The United States ◽  
Parental Violence ◽  
Youth Delinquency ◽  
The Impact ◽  
Children’S Exposure

This chapter reviews the degree to which empirical evidence demonstrates that families influence youth delinquency. Because they are most likely to be emphasized in life-course theories, this chapter focuses on parenting practices such as parental warmth and involvement, supervision and discipline of children, and child maltreatment. It also summarizes literature examining the role of children's exposure to parental violence, family criminality, and young (teenage) parents in affecting delinquency. Because life-course theories are ideally tested using longitudinal data, which allow examination of, in this case, the impact of parenting practices on children's subsequent behaviors, this chapter focuses on evidence generated from prospective studies conducted in the United States and other countries. It also discusses findings from experimental studies designed to reduce youth substance use and delinquency by improving the family environment.

scholarly journals Anthropomorphic Strategies Promote Wildlife Conservation through Empathy: The Moderation Role of the Public Epidemic Situation

2021 ◽  
Vol 18 (7) ◽  
pp. 3565
Author(s):  
Dan Yue ◽  
Zepeng Tong ◽  
Jianchi Tian ◽  
Yang Li ◽  
Linxiu Zhang ◽  
...  
Keyword(s):  
College Students ◽  
Behavioral Intention ◽  
Wildlife Conservation ◽  
Negative Emotion ◽  
Public Awareness ◽  
Negative Emotions ◽  
Experimental Studies ◽  
Wildlife Trade ◽  
Illegal Wildlife Trade ◽  
The Impact

The global illegal wildlife trade directly threatens biodiversity and leads to disease outbreaks and epidemics. In order to avoid the loss of endangered species and ensure public health security, it is necessary to intervene in illegal wildlife trade and promote public awareness of the need for wildlife conservation. Anthropomorphism is a basic and common psychological process in humans that plays a crucial role in determining how a person interacts with other non-human agents. Previous research indicates that anthropomorphizing nature entities through metaphors could increase individual behavioral intention of wildlife conservation. However, relatively little is known about the mechanism by which anthropomorphism influences behavioral intention and whether social context affects the effect of anthropomorphism. This research investigated the impact of negative emotions associated with a pandemic situation on the effectiveness of anthropomorphic strategies for wildlife conservation across two experimental studies. Experiment 1 recruited 245 college students online and asked them to read a combination of texts and pictures as anthropomorphic materials. The results indicated that anthropomorphic materials could increase participants’ empathy and decrease their wildlife product consumption intention. Experiment 2 recruited 140 college students online and they were required to read the same materials as experiment 1 after watching a video related to epidemics. The results showed that the effect of wildlife anthropomorphization vanished if participants’ negative emotion was aroused by the video. The present research provides experimental evidence that anthropomorphic strategies would be useful for boosting public support for wildlife conservation. However, policymakers and conservation organizations must be careful about the negative effects of the pandemic context, as the negative emotions produced by it seems to weaken the effectiveness of anthropomorphic strategies.

scholarly journals Image Statistics Preserving Encrypt-then-Compress Scheme Dedicated for JPEG Compression Standard

Entropy ◽  
2021 ◽  
Vol 23 (4) ◽  
pp. 421
Author(s):  
Dariusz Puchala ◽  
Kamil Stokfiszewski ◽  
Mykhaylo Yatsymirskyy
Keyword(s):  
Statistical Analysis ◽  
Image Encryption ◽  
Experimental Studies ◽  
Quality Measures ◽  
Input Image ◽  
Jpeg Compression ◽  
Image Statistics ◽  
Compression Stage ◽  
Wide Range ◽  
The Impact

In this paper, the authors analyze in more details an image encryption scheme, proposed by the authors in their earlier work, which preserves input image statistics and can be used in connection with the JPEG compression standard. The image encryption process takes advantage of fast linear transforms parametrized with private keys and is carried out prior to the compression stage in a way that does not alter those statistical characteristics of the input image that are crucial from the point of view of the subsequent compression. This feature makes the encryption process transparent to the compression stage and enables the JPEG algorithm to maintain its full compression capabilities even though it operates on the encrypted image data. The main advantage of the considered approach is the fact that the JPEG algorithm can be used without any modifications as a part of the encrypt-then-compress image processing framework. The paper includes a detailed mathematical model of the examined scheme allowing for theoretical analysis of the impact of the image encryption step on the effectiveness of the compression process. The combinatorial and statistical analysis of the encryption process is also included and it allows to evaluate its cryptographic strength. In addition, the paper considers several practical use-case scenarios with different characteristics of the compression and encryption stages. The final part of the paper contains the additional results of the experimental studies regarding general effectiveness of the presented scheme. The results show that for a wide range of compression ratios the considered scheme performs comparably to the JPEG algorithm alone, that is, without the encryption stage, in terms of the quality measures of reconstructed images. Moreover, the results of statistical analysis as well as those obtained with generally approved quality measures of image cryptographic systems, prove high strength and efficiency of the scheme’s encryption stage.

scholarly journals Ethanol/Gasoline Blends as Alternative Fuel in Last Generation Spark-Ignition Engines: A Review on CO and HC Engine Out Emissions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4034
Author(s):  
Paolo Iodice ◽  
Massimo Cardone
Keyword(s):  
Physicochemical Properties ◽  
Alternative Fuels ◽  
Experimental Studies ◽  
Alternative Fuel ◽  
Exhaust Emissions ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
The Impact

Among the alternative fuels existing for spark-ignition engines, ethanol is considered worldwide as an important renewable fuel when mixed with pure gasoline because of its favorable physicochemical properties. An in-depth and updated investigation on the issue of CO and HC engine out emissions related to use of ethanol/gasoline fuels in spark-ignition engines is therefore necessary. Starting from our experimental studies on engine out emissions of a last generation spark-ignition engine fueled with ethanol/gasoline fuels, the aim of this new investigation is to offer a complete literature review on the present state of ethanol combustion in last generation spark-ignition engines under real working conditions to clarify the possible change in CO and HC emissions. In the first section of this paper, a comparison between physicochemical properties of ethanol and gasoline is examined to assess the practicability of using ethanol as an alternative fuel for spark-ignition engines and to investigate the effect on engine out emissions and combustion efficiency. In the next section, this article focuses on the impact of ethanol/gasoline fuels on CO and HC formation. Many studies related to combustion characteristics and exhaust emissions in spark-ignition engines fueled with ethanol/gasoline fuels are thus discussed in detail. Most of these experimental investigations conclude that the addition of ethanol with gasoline fuel mixtures can really decrease the CO and HC exhaust emissions of last generation spark-ignition engines in several operating conditions.

scholarly journals Between Level Up and Game Over: A Systematic Literature Review of Gamification in Education

2021 ◽  
Vol 13 (4) ◽  
pp. 2247 ◽  
Author(s):  
Ana Manzano-León ◽  
Pablo Camacho-Lazarraga ◽  
Miguel A. Guerrero ◽  
Laura Guerrero-Puerta ◽  
José M. Aguilar-Parra ◽  
...  
Keyword(s):  
Systematic Review ◽  
Academic Performance ◽  
Game Design ◽  
Learning Strategy ◽  
Experimental Studies ◽  
Quasi Experimental ◽  
Current Lines ◽  
Meta Analyses ◽  
Game Elements ◽  
The Impact

Educational gamification consists of the use of game elements and game design techniques in the educational context. The objective of this study is to examine the existing evidence on the impact of educational gamification on student motivation and academic performance in the last five years in order to analyze its distribution over time, educational level, variables, and most used game elements, and know the advantages of its implementation in the classroom. For this, a systematic review is proposed through the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) methodology in three multidisciplinary databases, through an exhaustive search with inclusion and exclusion criteria on quantitative experimental studies that explore gamification in educational centers, which provide information about the most current lines of research. Fourteen studies were included in this review. These used experimental or quasi-experimental designs. Most of them report gamification as a valid learning strategy. The results support the conclusion that educational gamification has a potential impact on the academic performance, commitment, and motivation of students. Therefore, this study implies the need to expand research on the needs and challenges of students when learning with gamified techniques.

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