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A study and analysis showed that the increase in production and the quantity of nanofibers obtained from electrospinning may be provided by not only increasing the potential gradient between the electrodes, but also by the suitable distribution of the intensity of the electrostatic field. Through a numerical simulation using the finite element method, it was found that the intensity distribution of the electrostatic field is influenced not only by the potential gradient, type and shape of the electrodes, polymer properties and its concentration, humidity, ambient temperature, but also by other parameters, such as relative permittivity of the material and shape of the construction geometry. Experiments have been done with the functional baths for polymer solution deposition with a different geometry and relative permittivity. By using the proposed changes in design and relative permittivity for the experiment with the polymer PVP with TiO2 at 23.2 ± 3 °C and humidity of 14.4 ± 3 % and a potential gradient of 60 kV, the production of nanofibers can be increased by about 50 ± 3%. Key words: Electrospinning, optimization, nanofibers, FEM, reservoir

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Experimental and numerical analysis describes the design of noise removal effect of the friction pair of trapezoidal screw in a special device call Stick-Slip effect. Solution of the problems builds on previous measurements and testing sliding pairs, which was testing in last analysis. The pair worked in the special bath oil, its characteristics is that it does not support the mechanical lubrication. Measurements and calculations showed that it is necessary to enlarge the diameter for 32 kN load trapezoidal screw. This will reduce the contact pressure, which leads to polish the contact surfaces. You then slip together better and are not as easily stick slip effect.