Introduction/purpose: The study of vehicle suspension is a challenge for researchers in the field of vehicles regarding the impact of the suspension system on vehicle performances such as ride comfort, road holding, and working space. This paper presents the simulation of the Land Rover Defender 110 vehicle in the roll plane (half vehicle) in Simulink/MATLAB. The obtained results were compared with the results obtained in the ADAMS/CAR software package of the Land Rover Defender 110 simulation model previously experimentally validated. The Defender 110 vehicle has a dependent suspension system in both axles and a passive suspension type with four degrees of freedom (4 DOF). Methods: The equations of the system can be solved mathematically with a scheme in Simulink/MATLAB while half-vehicle modeling has been done in ADAMS/CAR. Results: The comparison of the vehicle characteristics obtained by the two simulation methods was done for three different scenarios, and it was noticed that there is a good correlation between them. Conclusion: It was concluded that the Defender 110 vehicle simulation model in Simulink/MATLAB is validated. The validated model can be used to perform suspension system optimization in future work.
Skeniranje slika i pretvaranje skeniranih informacija u digitalni format je aktivna oblast istraživanja. Skeniranje je automatizovan, brz i efikasan proces u poređenju sa tradicionalnim unosom podataka. Prepoznavanje cifara sa slika je izazovan zadatak. Tradicionalni pristupi za rešavanje ovog problema obično razdvajaju korake lokalizacije, segmentacije i prepoznavanja. Ovaj rad predstavlja jedinstven pristup koji integriše ova tri koraka korišćenjem duboke konvolucione neuronske mreže koja radi direktno na pikselima slike.
Introduction/purpose: Motor vehicles are complex dynamic systems due to spatial displacements, changes in the characteristics of components during their lifetime, a large number of influences and disturbances, the appearance of backlash, friction, hysteresis, etc. The aforementioned dynamic phenomena, especially vibrations, cause driver and passenger fatigue, reduce the lifetime of the vehicle and its systems, etc. Methods: In general, the movement of vehicles is carried out on uneven roads and curvilinear paths in the road. Not only do oscillatory movements cause material fatigue of vehicle parts, but they also have a negative effect on people's health. That is why special attention must be paid to the coordination of the mutual movement of the subsystems, and in particular, the vehicle suspension system, even at the stage of the motor vehicle design. For these purposes, theoretical, experimental or combined methods can be used. Therefore, it is very useful to have the experimental results of the oscillations of the vehicle subsystem in operating conditions, so the aim of this work was to use the movement of the 4x4 drive FAP 1118 vehicle in operating conditions (due to higher speeds - in road conditions) to define the conditions for testing oscillatory loads in laboratory conditions. Results: This is made possible by registering and identifying statistical parameters of registered quantities. Conclusion: Based on the measured data, the research can be programmed on shakers in laboratory conditions, and, at the same time, the size to be reproduced can be chosen as well.
Introduction/purpose: The hydraulic buffering valve has the greatest influence on the dynamic characteristics of power-shift transmission. The hydraulic buffering valve is a transmission element that controls increase in pressure in friction assemblies during the gear shifting process. By choosing the optimal control of pressure increase during shifting, reduction of dynamic loads in gear transmissions and thermal loads in friction assemblies is achieved. Methods: The paper analyzes the principle of one of hydraulic buffering valve solutions as well as the influence of certain parameters on the control of pressure increase. After the analysis of the working principle of the hydraulic buffering valve, a simulation model was developed in the MATLAB/Simulink software package. Results: The results obtained using the simulation model were compared with the experimental results of the selected pressure modulator solution. The selected hydraulic buffering valve was developed as part of the development of a device for power-shift transmission. The simulation results showed a satisfactory match with the experimental results. Conclusion: The developed simulation model enables a relatively easy and quick change of the parameters of the hydraulic buffering valve as well as a possibility of a faster and better understanding of the influence of individual parameters on pressure increase during the gear shifting process.
Motor vehicles are complex dynamic systems due to spatial vibratory displacements during movement, changes in the characteristics of components during life cycle, a large number of influences and disturbances, the occurrence of clearance, friction, hysteresis, etc. The mentioned dynamic phenomena, especially vibrations, cause fatigue of the driver and passengers, reduce the life cycle of the vehicle and its systems, etc. In the general case, the movement of motor vehicles is done on uneven roads (terrain) and curvilinear paths in flat roads (terrains). Oscillatory movements cause loading of vehicle parts, but they also negatively affect human health. Therefore, even in the design phase of the vehicle, special attention must be paid to the harmonization of the mutual movement of the vehicle subsystem, and in particular, the suspension system. Theoretical, experimental or combined methods can be used for this purpose, and it is very useful to have experimental results of vibration of the vehicle subsystems in real operational conditions. Therefore, it is very useful to have experimental results of vibration of vehicle subsystems in operational conditions. Bearing that in mind, the aim of this wpaper was to use the movement of FAP 1118, 4x4 wheel formula, in operational conditions (due to higher speeds - in road conditions) to define laboratory conditions for testing. This is made possible by registering and identifying statistical parameters of registered quantities.
The vehicle steering system is one of the most important systems on the vehicle, both in terms of safety and performance. Based on the geometry of the steering trapezoid, the geometry of the suspension system, the alignment angles of the wheels, as well as the characteristics of the tires, a mathematical model for the design of the formula student vehicle "Road Arrow" steering system was developed. Based on the dynamic state of the vehicle, the mathematical model provides information on the stress of the steering system, the torque on the steering wheel and the slip angles of the steered wheels. The mathematical model was developed using the MATLAB software, and validation of the results was performed by comparing the results with the ones obtained by simulations in MSC ADAMS. Analysing the obtained results, it is possible to conclude that the average value of relative error of the stress is approximately 15%, for slip angles of the steered wheels is approximately 7%, and the error for torque on the steering wheel is approximately 6%.
Traditional fuel-powered vehicle emissions have long been recognized as a major barrier to a sustainable environment, and their minimization could ensure both economic support for the sustainable societal fundament and pollution prevention. Electrifying light-duty vehicle fleets, such as taxis, could provide a financial return as well as bring significant economic and environmental improvements. This paper offers a ranked selection of electric vehicles that are presently available on the market, as reviewed by taxi service representatives, as well as their own evaluation of the criteria that influence this selection. This paper provides stability and support when making decisions by deploying stepwise weight assessment ratio analysis and a modified standard deviation method for calculating the subjective and objective weights of the criteria, as well as performing sensitivity analysis to determine how a particular criterion affects the multi-attributive border approximation area. A comparison ranking of the alternatives discovered how a change in the weight value of one of the criteria affected the ranking of the electric vehicle alternatives. According to the research, led by the battery capacity criterion and its values, the Volkswagen ID.3 Pro has the best results and is the taxi of choice in the Brčko District of Bosnia and Herzegovina. Furthermore, the research has demonstrated that the development of electric vehicles for taxi service purposes should strive to extend the range of these vehicles while reducing the battery charging time.
The aim of the research in the paper is to evaluate the state of rural settlements in Brčko District with regard to the development of rural tourism. Together with the Tourism Department of the Brčko District, five experts from the field of tourism were selected and they evaluated the current state of rural settlements in this part of Bosnia and Herzegovina. The evaluations were processed using the fuzzy approach with the SWARA (Stepwise Weight Assessment Ratio Analysis) multi-criteria decision-making method. Using this method, the weights of the used criteria were determined, representing the degree of development of conditions in rural settlements. The results showed that "rural facilities and services" are the best developed in rural settlements, while the criteria related to feelings and experiences are the least developed. Based on this research, it is possible to implement measures to strengthen certain criteria that have not been adequately developed in order to further improve rural tourism in Brčko District.
Abstract The subject of this research are the demographic trends and the educational system of the Republic of Srpska. The aim of the research is to define the concepts required to comprehend the demographic trends and to explore their implications for the educational system of the Republic of Srpska. In order to establish sustainable development in the Republic of Srpska, education being a key component therein, it is necessary to perceive its demographic resources in order to create an educational system. By means of empirical research with a presentation of results through factor and cluster analysis, generated quantitative and qualitative indices of demographic resources, particularly in the educational system. The Republic of Srpska as a whole belongs to type D, featuring poor demographic resources and characteristics, as well as prominent demographic disparities regarding spatial development. However, in order to increase the coverage, relevance and efficiency of completion of the education process, it is necessary to determine the strategic commitments to be accomplished together with certain quantitative demographic indicators of the achievement level (educational coverage of different generations). Demographic changes will pose a major challenge for policy makers and to the society in general across the upcoming decades and will require shaping new economic, tax, health, pension, educational, social, family and other policies that affect demographic changes. The research endeavour in this paper focuses on that very aspect, together with the respective applicative capabilities.
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