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Dana Sitányiová, Jean-Christophe Meunier and Jaroslav Mašek

Abstract

Transport is a social sector that is rapidly developing, changing and being influenced to the maximum extent by the technological development and innovation, among others, thus facing problems in staffing its several domains with appropriate and qualified personnel. This fact, makes the need for changes in training and education of future transport professionals. SKILLFUL project vision is to identify the skills and competences needed by the transport workforce of the future and define the training methods and tools to meet them. Paper focuses on mid-term results of the project.

Open access

Tomáš Skrúcaný, František Synák and Štefánia Semanová

Abstract

There are also the vehicles among the other vehicles in road traffic that have been modified without being authorised by their producer. These also include modifications such as structural modifications in the vehicle break system. Besides a brake system of road motor vehicles is one of the main factors influencing the active safety of vehicles. The design of the brake system, its technical condition and additional intervention in its construction may have a positive as well as negative impact on the braking distance length and the value of the mean braking deceleration achieved. The paper focuses on the influence of the brake disc diameter of the front axle on the achieved value of the mean braking deceleration and the braking distance length, while the braking system has been modified for several times without being approved by car manufacturer. The introductory part of the paper describes the braking distance sections and it also explains the term of mean braking deceleration. The following part of the paper deals with the measurement methodology, measuring equipment and the vehicle used during the measurements as well as procedures employed. The results obtained from the measurements are processed and presented in tables and also in graphs for greater clarity. The final part of the paper summarizes and evaluates the measured results. The importance of the paper lies in quantification of the influence of brake discs with different diameters on the vehicle active safety in the case of a particular vehicle.

Open access

Tomáš Skrúcaný, Martin Vojtek and Gabriel Suchter

Abstract

This paper due to determine an aerodynamic drag for different ways of tarpaulin fixation, specifically tarpaulin tension and disposition on platform-type body of a HDV. More positions of the tarpaulin were investigated. Determination of the resistances was done by coast down test of the vehicle according to Slovakian technical standard (STN). The aerodynamic drag was calculated from actual vehicle deceleration during the coast down test from the actual velocity changes. The vehicle actual velocity was measured by GPS logging device. Results are values of resistance, which affect the vehicle and their sum represents the actual engine power needed for vehicles driving.

Open access

Prapawan Thongsri

Abstract

Calcium manganese oxide (CaMnO3) polycrystalline was synthesized by solid state reaction (SSR) and hot-press (HP) methods. The powder of CaCO3 and MnO2 were mixed by ball milling then calcined at 850°C for 10 h and hotpressing at 850 °C for 1 h to obtain the CaMnO3 samples. The crystallography of the samples was analyzed by the X-ray diffraction (XRD). The microstructures of the samples were observed by scanning electron microscope (SEM). It was found that, the sintering process influence the crystalline perfection and have a direct impact on the mechanical properties of CaMnO3 and their aging behavior. The values of the effective elastic modulus was 6 GPa and Flexural strength was 0.417 MPa of CaMnO3 were found to be in the range of corresponding values for high performance and possibility fabricated n-type thermoelectric leg.

Open access

Dragoş Viorel Brezoi

Abstract

The paper presents a micro encapsulation method of α-Fe2O3 nanoparticles in PEG4000. A suspension of α-Fe2O3 nanoparticles and dissolved PEG is sprayed through a nozzle at atmospheric pressure. After rapid expansion, core-shell composite microparticles that don´t tend to agglomerate are obtained. Structure and morphology were investigated by electronic microscopy (TEM and SEM), X-ray diffraction (XRD), and spectral technique (UV-Vis and FTIR).

Open access

Dorin Angelescu and Gheorghe Ion Gheorghe

Abstract

As a result of the scientific concerns of the Doctoral School of Mechanical Engineering and Mechatronics at Valahia Târgovişte University in the field of robotics dedicated to security and surveillance, the scientific work "Intelligent Cyber- Mixmechatronic Micro-System for Monitoring and Controlling the Security and Surveillance Robots" is in the testing and experimentation phase, within the doctoral (industrial) thesis "Studies, research and contributions regarding the realization of a smart mecatronic robot for security and surveillance applications". The scientific work results in a highly efficient cybermixmecatronic system, unique in Romania, which will be used to control the mechatronic security and surveillance robot, respectively the propulsion and control of its displacement. The robot is controlled through Artificial Intelligence, using the Internet of Things (IoT), which is why the Intelligent Motion Control system must be optimized both in terms of response speeds and energy. At the same time, due to the varied and possibly unstable conditions of the displacement field, the system must meet stringent criteria of reliability, resilience, weather, stability and redundant solutions for on-site repair of potential failures during missions. The cybermixmecatronic system designed to move the robot must carry it safely at the mission site so that it can then return it back to the Command and Control Center. In the paper will be presented the original solution, applicable with minimum of specific modifications (according to the chassis used), to any type of robot requiring both operator-controlled or autoguid control. Thus, a complex project will be realized combining into a unitary Mechatronics, Integronics, Cyber-Mixmechatronics, Artificial Intelligence and Information Technology.

Open access

Ionel Rusa, Cornel Marin and Marius Baidoc

Abstract

The implementation of proactive maintenance is a necessity required by the development of modern technologies for the monitoring and exploitation of energy facilities and equipment. An important advantage of proactive maintenance is to permanently monitor the technical condition of the plant and equipment by vibration measurements and in the correct diagnosis in order to reasonably plan the required repairs. Turbo-aggregates are autonomous complex installations for producing electricity in refineries that operate in high power and high-speed modes. To monitor and control turbine vibrations, vibration sensors (uniaxial, biaxial and triaxial accelerometers) and proximity sensors (for relative displacements and lasers) are columned on bearing housings that transmit signals to data acquisition and processing systems as well is the Vibro-Expret diagnosis system presented in this paper.

Open access

Carmen Popa, Violeta Anghelina and Octavian Munteanu

Abstract

In this paper the deformation state of a circular and isotropic plate is analyzed, using as methods of comparison the analytical, the finite element and the experimental element methods. In the finite element method, the plate is analyzed by several programmes, as well as assembled with the respective container.

Open access

Ileana Nicoleta Popescu and Ruxandra Vidu

Abstract

The basic purpose of compaction is to obtain a green compact with sufficient strength to withstand further handling operations. The strength of green compact is influenced by the characteristics of the powders (apparent density, particle size and shape, internal pores etc.), the processing parameters (applied force, pressing type, and temperature) and testing conditions (strain rate etc.) Successful powder cold compaction is determined by the densification and structural transformations of powders (metallic powders, ceramic powders and metal-ceramic powder mixtures) during the compaction stages. In this paper, for understanding the factors that determine a required strength of compacted metal-ceramic powder mixtures, we present the densification mechanisms of different mixtures according to densification theories of compaction, the elastic-plastic deformations of mixture powders, the stressstrain relations and the relaxation behavior of compacted metal-ceramic composite parts and the particularities of each of them.