scholarly journals Estimation of the power of mechanical losses in the engine, transmission and wheels of car on the stand with running drums

2022 ◽  
Vol 14 (2) ◽  
pp. 38-45
Author(s):  
Sergey Krivoshapov ◽  
◽  
Vitaliy Kashkanov ◽  
Keyword(s):  
Experimental Studies ◽  
Experimental Methods ◽  
Measurement Procedure ◽  
Technical Condition ◽  
Vehicle Speed ◽  
Diagnostic Equipment ◽  
Method Of Least Squares ◽  
Tire Pressure ◽  
Advantages And Disadvantages ◽  
Primary Assessment

The efficiency of a car is considered through the amount of energy loss spent on transmission from the engine to the driving wheels of the car. Analytical and experimental methods for assessing mechanical losses are analyzed. The advantages and disadvantages of road and bench tests of a car in free run modes are indicated. A description of the diagnostic equipment - a stand with running drums, used to simulate the movement of a car in laboratory conditions is given. The components of the necessary measuring equipment for recording the speed and torque on the wheels of a car are considered. The list of primary measuring sensors and main transducers is indicated, which transmit information to the computer. The results of the car run-out on the stand are given: the change in the instantaneous speed from time to time. The primary assessment of the regression model is made and the values of the coefficients are obtained by the method of least squares of deviations of the vehicle speed. A mathematical model for the subsequent processing of experimental data has been developed. The purpose of mathematical modeling is to separate mechanical losses by power units separately for the engine, transmission and car wheels. An assessment was made of the amount of energy losses in the stand itself with running drums. The characteristic of the stand has been obtained, which must be taken into account in the measurement procedure. The results of experimental studies for the GAZ-31029 car are presented. The results of the influence of the technical condition of transmission units and vehicle wheels on the value of the power of mechanical losses are presented. Car tire pressure studies have been conducted. The graphical dependences of the power of mechanical losses depending on the speed of the car are obtained. Recommendations have been developed for diagnosing the general condition of the vehicle by the amount of mechanical losses at the stand with running drums. The ways of further improvement of the method are given. The main conclusions based on the research results are formulated.

scholarly journals Research on Model Predictive Control for Automobile Active Tilt Based on Active Suspension

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 671
Author(s):  
Jialing Yao ◽  
Meng Wang ◽  
Zhihong Li ◽  
Yunyi Jia
Keyword(s):  
Load Transfer ◽  
Ride Comfort ◽  
Active Suspension ◽  
Path Tracking ◽  
Roll Angle ◽  
Lateral Acceleration ◽  
Vehicle Speed ◽  
Model Predictive Controller ◽  
Advantages And Disadvantages ◽  
Predictive Controller

To improve the handling stability of automobiles and reduce the odds of rollover, active or semi-active suspension systems are usually used to control the roll of a vehicle. However, these kinds of control systems often take a zero-roll-angle as the control target and have a limited effect on improving the performance of the vehicle when turning. Tilt control, which actively controls the vehicle to tilt inward during a curve, greatly benefits the comprehensive performance of a vehicle when it is cornering. After analyzing the advantages and disadvantages of the tilt control strategies for narrow commuter vehicles by combining the structure and dynamic characteristics of automobiles, a direct tilt control (DTC) strategy was determined to be more suitable for automobiles. A model predictive controller for the DTC strategy was designed based on an active suspension. This allowed the reverse tilt to cause the moment generated by gravity to offset that generated by the centrifugal force, thereby significantly improving the handling stability, ride comfort, vehicle speed, and rollover prevention. The model predictive controller simultaneously tracked the desired tilt angle and yaw rate, achieving path tracking while improving the anti-rollover capability of the vehicle. Simulations of step-steering input and double-lane change maneuvers were performed. The results showed that, compared with traditional zero-roll-angle control, the proposed tilt control greatly reduced the occupant’s perceived lateral acceleration and the lateral load transfer ratio when the vehicle turned and exhibited a good path-tracking performance.

Experimental Studies on Axially Loaded Concrete Columns Confined by Different Materials

2008 ◽  
Vol 400-402 ◽  
pp. 513-518 ◽  
Author(s):  
Yong Chang Guo ◽  
Pei Yan Huang ◽  
Yang Yang ◽  
Li Juan Li
Keyword(s):  
Bearing Capacity ◽  
Glass Fiber ◽  
Failure Modes ◽  
Experimental Studies ◽  
Concrete Columns ◽  
Steel Tube ◽  
Ultimate Bearing Capacity ◽  
Advantages And Disadvantages ◽  
Axially Loaded ◽  
Normal Strength

The improvement of the load carrying capacity of concrete columns under a triaxial compressive stress results from the strain restriction. Under a triaxial stress state, the capacity of the deformation of concrete is greatly decreased with the increase of the side compression. Therefore, confining the deformation in the lateral orientation is an effective way to improve the strength and ductility of concrete columns. This paper carried out an experimental investigation on axially loaded normal strength concrete columns confined by 10 different types of materials, including steel tube, glass fiber confined steel tube (GFRP), PVC tube, carbon fiber confined PVC tube (CFRP), glass fiber confined PVC tube (GFRP), CFRP, GFRP, polyethylene (PE), PE hybrid CFRP and PE hybrid GFRP. The deformation, macroscopical deformation characters, failure mechanism and failure modes are studied in this paper. The ultimate bearing capacity of these 10 types of confined concrete columns and the influences of the confining materials on the ultimate bearing capacity are obtained. The advantages and disadvantages of these 10 types of confining methods are compared.

Think about it – can portrayals of homosexuality in advertising prime consumer-perceived social connectedness and empathy?

2017 ◽  
Vol 51 (1) ◽  
pp. 82-98 ◽  
Author(s):  
Nina Åkestam ◽  
Sara Rosengren ◽  
Micael Dahlen
Keyword(s):  
Design Methodology ◽  
Social Connectedness ◽  
Experimental Studies ◽  
Social Effects ◽  
Attitudes Toward Homosexuality ◽  
Content Type ◽  
Advantages And Disadvantages ◽  
Thought Listing ◽  
Societal Level ◽  
Practical Implications

Purpose This paper aims to investigate whether portrayals of homosexuality in advertising can generate social effects in terms of consumer-perceived social connectedness and empathy. Design/methodology/approach In three experimental studies, the effects of advertising portrayals of homosexuality were compared to advertising portrayals of heterosexuality. Study 1 uses a thought-listing exercise to explore whether portrayals of homosexuality (vs heterosexuality) can evoke more other-related thoughts and whether such portrayals affect consumer-perceived social connectedness and empathy. Study 2 replicates the findings while introducing attitudes toward homosexuality as a boundary condition and measuring traditional advertising effects. Study 3 replicates the findings while controlling for gender, perceived similarity and targetedness. Findings The results show that portrayals of homosexuality in advertising can prime consumers to think about other people, thereby affecting them socially. In line with previous studies of portrayals of homosexuality in advertising, these effects are moderated by attitudes toward homosexuality. Research limitations/implications This paper adds to a growing body of literature on the potentially positive extended effects of advertising. They also challenge some of the previous findings regarding homosexuality in advertising. Practical implications The finding that portrayals of homosexuality in advertising can (at least, temporarily) affect consumers socially in terms of social connectedness and empathy should encourage marketers to explore the possibilities of creating advertising that benefits consumers and brands alike. Originality/value The paper challenges the idea that the extended effects of advertising have to be negative. By showing how portrayals of homosexuality can increase social connectedness and empathy, it adds to the discussion of the advantages and disadvantages of advertising on a societal level.

Experimental Determination of KI for Short Internal Cracks

2001 ◽  
Vol 68 (6) ◽  
pp. 937-943 ◽  
Author(s):  
K. Bearden ◽  
J. W. Dally ◽  
R. J. Sanford
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Edge Crack ◽  
Series Solution ◽  
Experimental Studies ◽  
Experimental Methods ◽  
Internal Crack ◽  
Intensity Factors ◽  
Mode Stress

Since the pioneering discussion by Irwin, a significant effort has been devoted to determining stress intensity factors (K) using experimental methods. Techniques have been developed to determine stress intensity factors from photoelastic, strain gage, caustics, and moire´ data. All of these methods apply to a relatively long single-ended-edge crack. To date, the determination of K for internal cracks that are double-ended by experimental methods has not been addressed. This paper describes a photoelastic study of tension panels with both central and eccentric internal cracks. The data recorded in the experiments was analyzed using a new series solution for the opening-mode stress intensity factor for an internal crack. The data was also analyzed using the edge-crack series solution, which is currently employed in experimental studies. Results indicated that the experimental methods usually provided results accurate to within three to five percent if the series solution for the internal crack was employed in an overdeterministic numerical analysis of the data. Comparison of experimental results using the new series for the internal crack and the series for an edge crack showed the superiority of the new series.

scholarly journals Investigation of a Turbogenerator Based on the Vortex Expansion Machine with a Peripheral Side Channel

2021 ◽  
Vol 8 (1) ◽  
pp. F11-F18
Author(s):  
S.M. Vaneev ◽  
V.S. Martsynkovskyy ◽  
A. Kulikov ◽  
D.V. Miroshnichenko ◽  
Ya.І. Bilyk ◽  
...  
Keyword(s):  
Electricity Generation ◽  
Experimental Studies ◽  
Geometric Parameters ◽  
Working Fluid ◽  
Advantages And Disadvantages ◽  
Lateral Channel ◽  
Different Types ◽  
Flow Part ◽  
Special Stand ◽  
Constant Improvement

The creation of energy-saving turbogenerators is an essential component of the development of small energy systems. The gradual growth of interest in distributed electricity generation necessitates the constant improvement of these units. Moreover, they implement a more environmentally friendly generation method than when using microturbine units that use fuel to carry out the work process. Nowadays, turbogenerators are created based on different types of expansion machines, which have their advantages and disadvantages, given in this article. Compared to competitors, vortex expansion machines have good prospects and the necessary potential to expand their research and produce turbogenerators. An experimental vortex expansion machine with a peripheral-lateral channel and ability to change the geometric parameters of its flowing part was created to meet these needs. Experimental studies of the machine were performed on a special stand with air as a working fluid. As a result of the tests, the data were successfully obtained and processed. They are presented in the form of tables and graphical dependencies. The nature of the influence of thermodynamic parameters and geometric parameters of the flow part on the efficiency of the vortex expansion machine and turbogenerator based on it to further improve and create new turbogenerators is clarified.

scholarly journals ABOUT THE NECESSITY TO DETERMINE THE TECHNICAL CONDITION OF BUILDINGS OF STRATEGIC IMPORTANCE IN UNGHENI DISTRICT FROM REPUBLIC OF MOLDOVA

2021 ◽  
Vol XXVIII (2) ◽  
pp. 103-111
Author(s):  
Ion Rusu ◽  
◽  
Ion Cretu ◽  
Keyword(s):  
Research Methods ◽  
Housing Stock ◽  
Present Situation ◽  
Technical Condition ◽  
The Real ◽  
Republic Of Moldova ◽  
Advantages And Disadvantages

This paper deals with the need to determine the technical condition of strategic buildings, blocks of flats, which are in a precarious condition as well as engineering networks located within the Ungheni district. The article refers to the real present situation of buildings and housing stock from Ungheni municipality, including their periods of commissioning. Current research methods of buildings are exposed, being listed their advantages and disadvantages.

scholarly journals Theoretical and Experimental Studies for Inhibition Potentials of Imidazolidine 4-One and Oxazolidine 5-One Derivatives for the Corrosion of Carbon Steel in Sea Water

2020 ◽  
pp. 2776-2796
Author(s):  
Rehab M Kubba ◽  
Nada M. Al-Joborry ◽  
Naeemah J. Al-lami
Keyword(s):  
Carbon Steel ◽  
Density Functional ◽  
Sea Water ◽  
Physical Adsorption ◽  
Population Analysis ◽  
Experimental Studies ◽  
Experimental Methods ◽  
Equilibrium Geometry ◽  
Quantum Mechanical Method ◽  
Derivatives Of

Two derivatives of Iimidazolidin 4-one (IMID4) and Oxazolidin 5-one (OXAZ5), were investigated as corrosion inhibitors of corrosion carbon steel in sea water by employing the theoretical and experimental methods. The results revealed that they inhibit the corrosion process and their %IE followed the order: IMID4 (89.093%) > OXAZ5 (80.179%). The %IE obtained via theoretical and experimental methods were in a good agreement with each other. The thermodynamic parameters obtained by potentiometric polarization measurements have supported a physical adsorption mechanism which followed Langmuir adsorption isotherm. Quantum mechanical method of Density Functional Theory (DFT) of B3LYP with a level of 6-311++G (2d, 2p) were used to calculate the geometrical structure, physical properties and inhibition efficiency parameters, in vacuum and two solvents (DMSO and H2O), all calculated at the equilibrium geometry, and correlated with the experimental %IE. The local reactivity has been studied through Mulliken charges population analysis. The morphology of the surface changes of carbon steel were studied using SEM and AFM techniques.

scholarly journals TECHNICAL CONDITION OF CORRUGATED METAL TRANSPORT STRUCTURES

2021 ◽  
pp. 38-50
Author(s):  
J. J. LUCHKO ◽  
V. V. KOVALCHUK
Keyword(s):  
Bearing Capacity ◽  
Technical Condition ◽  
The Body ◽  
Soil Environment ◽  
Metal Structures ◽  
Advantages And Disadvantages ◽  
Methods Of Calculation ◽  
Analysis And Synthesis ◽  
The Impact ◽  
Corrugated Metal

Purpose. The purpose of the work is to establish the real technical condition of transport structures made of corrugated metal structures on the basis of the analysis of scientific and technical sources.And to analyze the experience of operation of metal corrugated structures in the soil environment and to form and generalize the problems of ensuring the reliability and durability of structures made of metal corrugated structures in the conditions of operation on railways and highways of Ukraine. Methodology. To achieve this goal, a review of scientific and technical sources and regulations of different countries on the technical condition of transport facilities in Ukraine was conducted. In particular, data on the distribution of bridges and pipes made of corrugated metal structures by mode of transport are given. It is shown that the development and implementation of new technologies for the repair of existing defective pipes and small bridges, both on the railways and highways of Ukraine is a very important issue. A thorough analysis of the experience of operation of corrugated metal structures in the soil environment in different countries was conducted. Data on the main inadmissible defects of pipes and the reasons of their development are given. CMS' (corrugated metal structures) corrosion and other defects are given. A number of examples of overpass defects, collapse of bridges and structures with MCS in operation are presented. The qualitative indicators of metal corrugated structures, their advantages and disadvantages are also considered, the problems and the analysis of ensuring the reliability and durability of the structures with CMS in the conditions of operation on the railways and highways of Ukraine are formulated. Findings. An analysis of domestic and foreign scientific and technical sources on the technical condition of transport facilities in Ukraine was conducted. In particular, the experience of operation of corrugated metal structures in different countries of the world is studied and generalized. The analysis and synthesis of problems of ensuring the reliability and durability of buildings with CMS in the conditions of operation on the railways and highways of Ukraine. Originality. As a result of the analysis of the technical condition of transport facilities operated on railways and highways of Ukraine, it was found that about 15 % of transport facilities – small and medium bridges and culverts on Ukrainian railways and about 45 % of transport facilities on Ukrainian roads have unacceptable defects and require immediate repair and replacement. Also, it was established on the basis of research that there are no methods for assessing the load-bearing capacity of transport facilities with CMS in the presence in the body of the embankment of the railway or highway metal corrugated structures with a diameter greater than 6 m. It was determined that standards don't include regulations on design and monitoring of CMS on railway tracks. Practical value. On the basis of these data it was possible to offer directions of theoretical and experimental research and methods of calculation, tests of CMS and diagnostics of a technical condition of transport structures with CMS. In particular, the measurement of the impact of the environment on the bearing capacity of the CMS and the measurement of residual deformations of the corrugated metal pipe on the railway track. Execution of the analysis and synthesis of methods of calculation of transport constructions with CMS will lead to improvement of methods of calculation of CMS.

scholarly journals Visual odometry in local underwater navigation problems

2021 ◽  
Vol 2091 (1) ◽  
pp. 012053
Author(s):  
I M Azhmukhamedov ◽  
P I Tamkov ◽  
N D Svishchev ◽  
A V Rybakov
Keyword(s):  
Experimental Studies ◽  
Visual Odometry ◽  
Ecological Monitoring ◽  
Video Stream ◽  
Video Data ◽  
Work Processes ◽  
Underwater Robots ◽  
Advantages And Disadvantages ◽  
Local Navigation ◽  
Slam Algorithm

Abstract The work processes of the ORB-SLAM algorithm are presented. The results of experimental studies on temporal comparisons of the operation of the algorithm with different parameters and cameras are presented. The necessity of forming a visual odometry (VO) system as a local navigation of remote-controlled and autonomous underwater robots has been substantiated. The two most suitable odometry methods in the underwater environment are described, such as their advantages and disadvantages. The work processes of the ORB-SLAM algorithm are presented. The results of experimental studies on temporal comparisons of the operation of the algorithm with different parameters and cameras are presented. The procedure for preparing video data is described: processing a video stream, adjusting camera parameters for calibration. The experiments represent the testing of the ORB-SLAM3 algorithm on a sample of video filmed as part of the ecological monitoring of the Caspian shelf in 2020.

scholarly journals Definition of Set of diagnostic Parameters of System based on the Functional Spaces Theory

2019 ◽  
Vol 18 (4) ◽  
pp. 949-975 ◽  
Author(s):  
Valentin Senchenkov ◽  
Damir Absalyamov ◽  
Dmitriy Avsyukevich
Keyword(s):  
Fourier Series ◽  
Experimental Studies ◽  
Numerical Procedure ◽  
Physical Nature ◽  
Convergent Series ◽  
Technical Condition ◽  
Partial Sums ◽  
Diagnostic Tools ◽  
Diagnostic Parameters ◽  
Integrable Functions

The development of methodical and mathematical apparatus for formation of a set of diagnostic parameters of complex technical systems, the content of which consists of processing the trajectories of the output processes of the system using the theory of functional spaces, is  considered in this paper. The trajectories of the output variables are considered as Lebesgue measurable functions. It ensures a unified approach to obtaining diagnostic parameters regardless  a physical nature of these variables and a set of their jump-like changes (finite discontinuities of trajectories). It adequately takes into account a complexity of the construction, a variety of physical principles and algorithms of systems operation. A structure of factor-spaces of measurable square Lebesgue integrable functions, ( spaces) is defined on sets of trajectories. The properties of these spaces allow to decompose the trajectories by the countable set of mutually orthogonal directions and represent them in the form of a convergent series. The choice of a set of diagnostic parameters as an ordered sequence of coefficients of decomposition of trajectories into partial sums of Fourier series is substantiated. The procedure of formation of a set of diagnostic parameters of the system, improved in comparison with the initial variants, when the trajectory is decomposed into a partial sum of Fourier series by an orthonormal Legendre basis, is presented. A method for the numerical determination of the power of such a set is proposed. New aspects of obtaining diagnostic information from the vibration processes of the system are revealed. A structure of spaces of continuous square Riemann integrable functions ( spaces) is defined on the sets of vibrotrajectories. Since they are subspaces in the afore mentioned factor-spaces, the general methodological bases for the transformation of vibrotrajectories remain unchanged. However, the algorithmic component of the choice of diagnostic parameters becomes more specific and observable. It is demonstrated by implementing a numerical procedure for decomposing vibrotrajectories by an orthogonal trigonometric basis, which is contained in spaces. The processing of the results of experimental studies of the vibration process and the setting on this basis of a subset of diagnostic parameters in one of the control points of the system is provided. The materials of the article are a contribution to the theory of obtaining information about the technical condition of complex systems. The applied value of the proposed development is a possibility of their use for the synthesis of algorithmic support of automated diagnostic tools.

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