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Open access

Tomáš Skrúcaný, Saša Milojević, Štefánia Semanová, Tomáš Čechovič, Tomasz Figlus and František Synák

Abstract

The article deals with the problem of electric power production in terms of environmental impact, in particular the energy efficiency of its production to utilize primary sources. The efficiency of its production directly depends on the composition of primary sources and technologies used. Difference in efficiency by converting various forms of energy into electrical power and their ratio in the use directly affect the resulting efficiency, production of emissions and thus the environmental impact. Electric traction, its production, is burdened less efficient than other types of tractions used in transport, but at the final reconciliation of their consumption in vehicles, this difference decreases or delays because the vehicles themselves work with different conversion efficiency of its traction on mechanical work, vehicle driving.

Open access

Dana Rozová and Martin Šustr

Abstract

The continuity of activity field during the crisis situations is a way, how to reduce activities which is harmless for the transport. The goal is ensure minimal demanded level of services performed in the transport branch. This minimal level for performing the transport services are necessary for train operating.

Open access

Milan Škorupa, Tomáš Čechovič, Martin Kendra and Borut Jereb

Abstract

Transport is one of the human activities that increases the amount of greenhouse gases in the air. CO2 is the main cause of global warming and contribute for around 80 % of all greenhouse gas emissions. The paper presents CO2 production based on the amount of sold fuel in Slovakia and Slovenia. Based on the obtained data, the calculations about the production of CO2 according to the type of fuel was made. The conducted research has focused on the issue of traffic congestion and to reduce CO2 emissions by 15 % in total by 2030, as Slovakia and Slovenia concluded an agreement with other EU members in 2009. External costs calculation was made with average price of 1 tonne emission credit in 2016 and with presumed average price in 2019. The case study takes into account the consumption of the gasoline and diesel in transport throughout all Slovakia and in Slovenia.

Open access

Juraj Čamaj, Jaroslav Mašek and Martin Kendra

Abstract

Users in transport, forwarding and logistics companies use the mobile technologies for connect to existing information systems. By solving the ERIC Mobile project, these services will also be available on mobile devices. The article is aimed at lancing the requirements of all types of customers for the ERIC Mobile app. After the basic characteristics of the mobile device, the operation systems, the application development typology, the authors focus on the developing application “ERIC Mobile”. The aim of the article is to provide relevant requirements for further research and development of the software application of the rail freight information centre in Europe for end users of mobile devices such as smartphones and tablets.

Open access

Ivona Camelia Petre, Adrian Catangiu, Ileana Nicoleta Popescu, Dan Nicolae Ungureanu, Alexis Daniel Negrea, Aurora Anca Poinescu, Maria Cristiana Enescu, Elena Valentin Stoian and Veronica Despa

Abstract

The aim of the paper was to develop a device (“pin-on-disc” type) for the measurement of friction in plane friction couplings with sliding movement. On tribometric device (made in our laboratory) we can measure the friction force, friction coefficient and wear, for different loading conditions, speeds, time and material coupling.

For the measurement of the frictional force as well as of the coefficients of friction, mainly the method with a resistive tensiometric transducer is used. With a DataQ DI 245 data acquisition board it is possible to record up to 2 kHz frequencies in the range of -10 ÷ +10 mV with a resolution of 13 bits. To test the functionality of the device, a preliminary test was carried out for a steel pin- on- cast iron disc, for different values of the normal pushing force. The device was calibrated and the measurement results were recorded and processed on the computer.

Open access

Florina Violeta Anghelina, Dan Nicolae Ungureanu, Carmen Popa, Elena Valentina Stoian, Ileana Nicoleta Popescu, Cristiana Maria Enescu and Constantin C. Anghelina

Abstract

In this presentation are evidenced instrumental characterization by Electronic Scanning Microscopy (SEM) equipped with EDS / WDS of aluminum alloys such 2024 alloy with multiple synergistic purposes as: acquisition of new knowledge, increase the amount of information obtainable about the material, increasing the efficiency and the quality of the tests, characterization of special destination alloys and assessing their conformity with the specified requirements. In this direction, it requires both the knowledge the test methods (theoretical basis, test method, procedure relating to the method, quality assurance testing) as well material characteristics investigated. These aspects are necessary for test system design, and preliminary interpretation of experimental results.

Open access

Elena Valentina Stoian, Vasile Bratu, Cristiana Maria Enescu and Dan Nicolae Ungureanu

Abstract

Aim of the study is to present the technological process of obtaining cast iron with lamellar graphite for use in the manufacture of cylinder liners, and to identify the main alloying elements and track their influence on the mechanical properties of cast iron with lamellar graphite.

Also paper presents analysis of 20 batches of cast iron with lamellar graphite, which are made of cylinder liners, in terms of chemical composition and the mechanical properties.

After the analysis of the 20 castings of cast iron Fc 250 it is observed that: the increase in the carbon content shows a decrease of the tensile strength and hardness of the gray cast iron; the increase in silicon content shows a decrease in hardness and tensile strength. Decreasing the amount of graphite and especially the alloy of silicon iron lead to hardness increase 1% Si increases hardness by 50 HB). A statistical analysis has been performed on the data obtained that accounts for changes in alloying additions. A modeling and optimization of mechanical properties (tensile strength and hardness) was performed according to the percentages of carbon, silicon and manganese. Mathematical modeling found that the hardness and traction resistance of the cast iron decreased with the increase in carbon, silicon and manganese content.

Open access

Cristian Radu Badea

Abstract

The aim of this paper is to provide an introduction into the inertial motion analysis field, focusing its attention on the analysis that is performed using modern mechatronic inertial motion capture systems, highlighting both the advantages and drawbacks of using such a system and outlining the main constituent elements of these systems as well as the necessary steps to be carried out in order to be able to accomplish such analysis.

A modern mechatronic inertial motion analysis system’s evolution it’s based on MEMS (Micro-Electro-Mechanical-Systems) sensory network, each of which contains a combination of accelerometer, gyroscope, magnetometer. The signals from these MEMS are processed, by a microcontroller, using advanced algorithms in order to provide accurate data regarding body’s segments kinematics, global positioning and magnetic field. Those data are being transferred to a biomechanical model for the analysis. Despite its tremendous advantages, such as portability and real-time analysis capabilities, over alternative motion analysis systems, such as optical or mechanical systems, that based on external transmitters and/or video camera networks, restricting their use to special laboratory conditions and/or large workspace, mechatronic inertial systems are not based on an external infrastructure, they present a major disadvantage, namely the positional drift. The estimation of the human subject body’s segments positions and orientation, absolutely requires an initial calibration procedure, called „sensor to segment calibration”, that starts from the positional and orientation information received from the MEMS network, which are then transferred onto a biomechanical (scaled) model of the human body.

Open access

Vladimir Dragoş Tătaru and Mircea Bogdan Tătaru

Abstract

The wheel is a very important machine part. It is very often found in the construction of the vehicles. Therefore its dynamics must be studied properly. In the paper is presented the dynamical survey of a wheel which climbs on an inclined plane under the action of an active moment produced by an engine. The case of rolling without sliding was taken under consideration in the paper. The approach of the problem is a numerical one. The differential equations describing the movement of the motor wheel were written in matrix form. The paper also presents a method of removing of the constraint forces from the differential equations of motion.