A zero-dimensional, one zone model of engine cycle for steady-state regimes of engines and a simplified procedure for indicator diagrams analysis have been developed at the Laboratory for internal combustion engines, fuels and lubricants of the Faculty of Mechanical Engineering in Kragujevac. In addition to experimental research, thermodynamic modeling of working process of diesel engine with direct injection has been presented in this paper. The simplified procedure for indicator diagrams analysis has been applied, also. The basic problem, a selection of shape parameters of double Vibe function used for modeling the engine operation process, has been solved. The influence of biodiesel fuel and engine working regimes on the start of combustion, combustion duration and shape parameter of double Vibe was determined by a least square fit of experimental heat release curve.

The increase in the number of electric bicycles worldwide has resulted in a rise in the number of traffic accidents involving e-bicyclists. Previous studies have been based on analyzing the use, advantages and disadvantages of e-bicycles, whereas only a small number of studies have been focused on analyzing the e-bicycle traffic safety, particularly the factors leading to the occurrence of traffic accidents. One of the factors affecting the occurrence of traffic accidents is the incorrect perception of the e-bicycle speed by other traffic participants. To examine the mentioned problem, the authors of this paper conducted an experimental study to determine what affects the e-bicycle speed perception. The experiment included 175 participants, aged 18 to 50. The research was conducted under laboratory conditions using a driving simulator, at different e-bicycle speeds (10 km/h, 20 km/h and 30 km/h), in the situations in which the e-bicyclist was (not) using a reflective vest. The results show statistically significant differences in the e-bicycle speed perception when the e-bicyclist does not use/uses a reflective vest. Besides, the driving licence categories of traffic participants and their driving experience also have a significant impact on the perception of the e-bicycle speed.

More than half a century, the scientific community is trying to understand the mechanisms and conditions of pollution dispersion within urban areas. Thereat, special attention has been focused on specific areas, such as a street canyon, in which harmful concentrations higher than allowed are more likely registered. However, there is still a controversy about the conditions of occurrence and impact of the individual air pollution components due to fluctuations of key contributions. Given that OSPM model is a well-known semi-empirical model specializing in the assessment of air quality within a street canyon, after its testing and validation, the results of subsequent simulations were used as a basis for planning a special experiment in order to implement 48 full factorial designs, where using the response surface methodology, as the final objective, an answer was precisely given on the impact and contribution of urban air pollution components. In addition to the main objective of this study, as a secondary, but not less important result defining emission factors for CO and NOx can be emphasized, which to date have not been determined for the fleet of the Republic of Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR 35041]

It is very important during production to take into account the requirements regarding to recycling of vehicles. On this manner it is possible reuse of consisting materials and optimization of End-of-Life Vehicles. In European Union has defined targets to be achieved in the future for the recycling rate of vehicles at the end of their service cycle. Directive of the European Parliament and of the Council 2000/53/EC regulate waste management in the vehicle sector. This manuscript presents in global the international legislative in this field, regarding to the situation in Republic of Serbia. As contribution, during production of domestic city bus running on natural gas, performed the replace of material for bus dashboard on the basis of plastic and polyurethane foam, with ecological material with carbon inserts. The requirements for dismantling, reuse and recycling are integrated in the design of new bus.

The research of influencing factors on the electricity consumption of electric buses Higer KLQ6125GEV3 in real working conditions is the result of experimental measurements conducted on the EKO 1 line in Belgrade over a long period which included typical seasonal periods (winter, summer, transitional) of E-bus operation as well as characteristic periods of work during the day (peak load, intermediate period, first/last departures). The results of this research are the basis for reviewing and ranking the influential factors on the electricity consumption of E-buses that are of great importance in planning operations of the line, analysis of energy efficiency and operating conditions.