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Compliance with EU regulations for environmental protection sets new performance criteria to fuel injection technology in modern combustion engines for passenger and commercial vehicles. According to EURO-5 norm regulation the quality of the air/fuel mixture combustion depends mainly on an adequate spraying of the fuel, with as fine as possible droplets. The paper introduces the construction, validates...
This paper presents a comparative study between three five-level converters. Control strategies and simulation results are presented in order to show the principles that led to the development of these converters. Advantages and disadvantages are presented in view of the total harmonic distortion factor, the number of semiconductor devices and flying capacitors and the energy stored in the flying...
Improving education system can be made by assuming some functional principles in other areas that are already proven in practice. By identifying the component parts of an adaptive cybernetic system in engineering training system and adding them specific indicators and procedures a new form of training was obtained. This new kind of training is more efficient and predictable both professionally and...
The authors aim to analyze different types of motivation and the methods of maintaining motivation throughout the learning process for both students and professors, in terms of the characteristics of the Bologna process, whose central concept is "the student — a partner in the educational process". The paper is based on a significant amount of literature which analyzed motivation theories...
Normal operation of electrical machines and equipment is conditioned, among others, by the insulation systems status. Therefore, diagnosing insulation systems in order to estimate their lifetime reserve is very important, both for new equipment and especially for those in operation. This paper presents a lifetime calculation of a medium power electrical machine, whose operating cycle is known. For...
After the classes of hard ferrites and AlNiCo magnets, the research have promoted a new class of advanced magnetic materials based on rare earth materials, the Sm-Co and NdFeB types. These hard magnetic materials are used today as permanent magnets in a large variety of applications, due to their advantages: compact structure, light weight, small size, high energy density. Precision application as...
Using the experimental data acquired from three subjects, an offline analysis of the EEG signals has been performed in order to detect the attentive reading. The experiment involved 10 seconds reading trials alternating with 10 seconds of rest. The experimental data consists in 4 data sets recorded in different conditions, each set including from 182 to 320 trials. Half of these trials are reading...
The susceptometer method is used to determine the magnetic susceptibility and the permanent magnetization of weakly-magnetized object through measurement of the force exerted on this object in the magnetic field gradient of a strong permanent magnet. In suceptometer method is essential to have a good estimation of the characteristics of this magnet. Experiments and measurements ware performed using...
Within the essay an on-line diagnosis system used at the static excitation equipment is presented. An advantage of the static excitation systems is the greater response speed beside classic systems. This modern on-line diagnosis system for static excitation systems allows the acquisitioning of quality energy at minimum costs as well as reducing maintenance times, all these leading to the customer's...
This paper deals with the numerical analysis of a three-phase Small Power High Speed Induction Motor (SPHSIM) with copper rotor cage. The 2D numerical simulations are carried out using the Finite Element Method (FEM) based professional software package Flux. Two numerical approaches of the studied SPHSIM were used in the study, a 2D plane-parallel model and a skewed 2D one. The numerical results are...
This paper analyzes the dynamic stability of a reluctance synchronous motor rated at 1,5 kW by means of some simulations in dynamic regime. For doing this, there are presented the two axes theory mathematical model of the motor, the Matlab-Simulink program conceived with the help of this model and the simulations that have been obtained this way. Two of the most common possible disturbances are considered:...
The mechanical expansion is a technological dimensional calibration operation which is proper for the manufacturing process of the longitudinally large size pipes regulated by the standard API 5L (American Petroleum Institute). The process involves the application of forces between 600 and 1500 tf on a set of tools in contact with friction both between the constituents and the inner surface of the...
Electricity is more than energy: it is a vital component of our lives, playing an important role in the economy of many countries. Wherever electricity is generated, electromagnetic fields are created. The strong development of information technology had provided new possibilities in monitoring and diagnose of electrical equipment and devices. The purpose of this paper is to highlight the posibility...
A numerical model of a Transverse Electromagnetic Mode cell is constructed and analyzed from the perspective of using it for dosimetric studies of biological samples exposed inside it to radiofrequency (RF) fields. A TEM cell offers a controlled environment for biological experiments looking for electromagnetic field effects, being a versatile variant of free-space exposure. The specific absorption...
When thinking of quantity measuring, out of all properties of a phenomenon, body or substance, the temperature of a point or zone of interest is probably (if not surely) the most important parameter to determine. This paper introduces a high-performance temperature measuring system capable of acquiring data from a network of integrated temperature sensors. The system's design is based on latest integrated...
The electroencephalography (EEG) is a medical diagnosis technique that measures the electrical brain activity. It is a test that provides evidence of how the brain functions, in real time. The EEG is primarily use for diagnosis, detect and localize cerebral brain lesions, aid in the studying of epilepsy, diagnosing mental disorders, and allowing observation and analysis of brain responses to sensory...
The paper presents the design and analyze of a permanent magnet brushless machine for a hybrid electric scooter. Different combinations of slots number, magnetic poles, and concentrated windings are tested based on the speed-cycle and power-cycle of the scooter. A machine prototype has been build. The experimental data are used to validate the simulation model. A method of increasing the torque density...
This paper wants to present, the main problems of unwanted disturbances that can affect the shape of the electrocardiograph — ECG signal. The objective of the paper is to show some studies, regarding to the problems that are created by the noisy mass and how can be removed from ECG signals.
The influence of impurities on the efficiency of photovoltaic cells is a widespread problem. Manufacturers of photovoltaic panels estimate that the absence of a rigorous regular cleaning of cells may cause a significantly reduction of electricity production. Deposits left by birds, dust pollution caused by traffic or farming activities accumulate rapidly and other factors such humidity which can appear...
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