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The article presents methods for preliminary statistical analyses of selected maintenance parameters of vehicles in road transport companies. The methodology is illustrated by presenting the results of calculations of the intensity of maintenance and the cost of parts and repairs of cars in the Lublin Regional Branch of the Polish Post Logistics Centre. These results provide comparative material useful in the evaluation of the maintenance efficiency of various road transport systems.

The subject of this article is an introduction of the concept of a device for deep drawing in extreme conditions. In this case, extreme conditions represents drawing process in vacuum by high temperatures required by molybdenum sheets forming. The first part of the paper is about the functional, structural, economical, technological, operational, safety, environmental, legal and design requirements. The second part of the article deals with description of possible variants of the mechanism structure. The paper describes also the results of the research work by evaluating the variants. The variants scores were rated by parameters, which are essential for properly work of the mechatronic system.

In this study, a novel rotary cleaning device was used for the separation and cleaning of wheat grains. This research analyzed the influence of the inclination angle of the sieve drum (K) of the device on the quality of these processes. In this article, the results obtained for four selected rotational speeds (nb) of the sieve drum are presented. The quality of the separation and cleaning of the wheat grains was evaluated using three cleaning process parameters: coefficient of plump grain mass separation (Wz), coefficient of fine impurities separation (Wd), and total coefficient of cleaning effectiveness (E). Based on statistical analysis of the results, the inclination angle of the sieve drum had a significant effect on the quality of the wheat grain separation process. Coefficient Wz was highest for sieve drum inclination angles of K = 0° and K = 2.5°, whereas Wd was highest for K = -2.5°. The total coefficient of cleaning effectiveness (E) was characterized by different values for different inclination angles of the sieve drum. Keywords: Cleaning effectiveness, Conical sieve, Rotary cleaning device, Wheat grain cleaning.

The article describes modeling and simulation of the vehicle physical model. The vehicle model is simplified and it is made up of body and 4 tires. The model contains elementary information of the vehicle geometry - dimensions and center of gravity position. These information about the vehicle are sufficient for mathematical description of vehicle. The model is made of basic elements like engine, gearbox, differential and tires, which are represented by blocks. The model includes also other blocks, which are used to show measured outputs and control blocks, that make the vehicle mechatronic systems controllable according the driver model inputs. There are also studied the forces on tires and the engine speed of the vehicle model.

Electric or hybrid vehicles are becoming increasingly common on roads. While electric vehicles are still more or less intended for city traffic, hybrid vehicles allow normal use due to wider driving range. The use of internal combustion engines in hybrid drives is still an inspiration to find the way to reduce the produc-tion of emissions. Numbers of alternative energy resources were studied as a substitution of conventional fuels for hybrid vehicles drives worldwide. The paper deals with the possibility of using alternative fuels as CNG, LPG and LNG in combination with hybrid drive of a midibus with the capacity of 20 passengers. Various aspects and techniques of hybrid vehicles from energy management system, propulsion system and using of various alternative fuels are explored in this paper. Other related fields of hybrid vehicles such as changes of vehicle weight or influence of electric energy sources on the total vehicle emission production are also included.

The article presents the newest technologies of the 3D printing of metal objects. The technologies were classified on account of the way of laying and joining material. The research results are indicated the advantages and the disadvantages of the various methods of joining metal material. There is presented a brief description of the technology of the 3D printing which using a metal material, and lists of manufacturers who offering the device in the technology.