ANALYTICAL RESEARCH ON THE GRIP VARIATION OF TWO-AXLE CAR

Summary. This paper presents a theoretical investigation on the decrease in grip coefficient of a car due to the car mass changes for three different running conditions- straightforward, motion in curve and braking. The grip of two types of cars - with forward and rear traction, equipped with three models of tires are studied. The results show a significant decrease of the grip coefficient in longitudinal and lateral directions

Software Provisioning of the Protech Integrated Engineering Automation System

This is a presentation of the basic principle, operational functions and modules of the software for planning, programming and control of the serial production in the engineering automation system environment. We specified the software provisioning of the particular application and the benefits from its use in the manufacture process. There is a description of the available data bases for the input of the basic technological information about the work-pieces and details and for setting-up of the metal-processing tools. This product traces the technological sequence and the specifics of the production process of machines with computer and numerical control (CNC), the direct connection and dependency of the individual modules within the processing and exchange of the running current information

Clustering kinetics during natural ageing of Al-Cu based alloys with (Mg, Li) additions

Room temperature solute clustering in aluminium alloys, or natural ageing, despite its industrial relevance, is still subject to debate, mostly due to its experimentally challenging nature. To better understand the complex multi-constituents' interactions at play, we have studied ternary and quaternary subsystems based on the Al-Cu alloys, namely Al-Cu-Mg, Al-Cu-Li and Al-Cu-Li-Mg. We used a recently introduced correlative technique using small-angle neutrons and X-ray scattering (SANS and SAXS) to extract the chemically resolved kinetics of room temperature clustering in these alloys, which we completed with differential scanning calorimetry (DSC) and micro-hardness measurements. The comparison of the clustering behaviours of each subsystem allowed us to highlight the paramount role of Mg as a trigger for diffusion and clustering. Indeed, while a strong natural ageing was observed in the Al-Cu-Mg alloy, virtually none was shown for Al-Cu-Li. A very slight addition of Mg (0.4%) to this system, however, drastically changed the situation to a rapid formation of essentially Cu-rich hardening clusters, Mg only joining them later in the reaction. This diffusion enabling effect of Mg is discussed in terms of diffusion mechanism and complex interactions with the quenched-in vacancies

Tangible and Personalized Smart Museum Application

This paper presents the architecture of a Web app designed to deliver personalized content to museum visitors both indoors and outdoors. The app uses a tangible type of interface to obtain information about the museum's exhibits. For this purpose, each exhibit can be associated with an NFC tag, a Bluetooth Low Energy (BLE) beacon or a geofence in open-air museums. The service automatically profiles its users based on statistics about the preferred type of exhibits, media formats and time spent viewing each exhibit. Visitors can get the information they want about an exhibit even when the app is not running. Push notifications are used for this purpose. The necessary experiments have been conducted to prove the applicability of the service for real-time delivery of personalized content

COMPARISON OF GENETIC ALGORITHM AND NEURAL NETWORK APPROACHES FOR THE PROGNOSIS OF MECHANICAL IDLE RUNNING LOSSES IN AGRICULTURE TRACTOR TRANSMISSION

An experimental investigation of mechanical idle running losses in an agriculture tractor transmission was used to collect a wide range of data. The influence of the engine rotation speed, the number of switched-on gears, and the oil level in the transmission gearbox on the idle running losses was determined. Adequate regression models in cases of switched-on and switched-off PTO were received. A genetic algorithm was used to optimize mathematical models obtained using regression analysis. A feed-forward artificial neural network was also developed to estimate the same experimental data for mechanical idle running losses in transmission. A back-propagation algorithm was used when training and testing the network. A comparison of the correlation coefficient, reduced chi-square, mean bias error, and root mean square error between the experimental data and fit values of the obtained models was made. It was concluded that the neural network represented the mechanical idle running losses in tractor transmission more accurately than other models

A STUDY OF THE FUEL CONSUMPTION OF HYBRID CAR TOYOTA YARIS

The paper presents the experimental results from a complex study of the fuel consumption of a hybrid car Toyota Yaris. Original data for motion at different constant speeds are obtained. The economical and energy characteristics of the car are observed and analyzed. Three typical urban and three inter-city routes are investigated. A significant decrease in the fuel consumption of the hybrid car is witnessed when it runs in urban conditions at “Eco Mode”. The motion on inter-city route, including short town passages and highway parts, is also investigated. The obtained original data are higher than the fuel consumption given by the producer and, practically, equal to the ones of the conventional gasoline car. The study indicates that the effect of a hybrid system is significant in urban conditions and is more evident at “Eco Mode”