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Abstract

The study explored the impact of experimental manipulation of body schema on creative potential in midadolescence. The experiment was conducted in a group of 140 adolescents at the age of 14-16: 68 boys (M = 15.03; SD = .93) and 72 girls (M = 15.01; SD = .81), randomly allocated to equinumerous groups: experimental and control. The aim of experimental manipulation was to obtain a temporarily disturbance of body schema. It was gained by the use of glasses reversing the field of vision in the vertical up/down plane, and measured by the Body Schema Disturbance Questionnaire. In both groups the Urban and Jellen’s Test for Creative Thinking – Drawing Production (TCT-DP, Urban & Jellen, 1986) was administered twice (in A and B versions, randomly selected). Statistical analyses was run with a mixed model ANOVA (2 drawings x 2 groups x 2 sexes). The interaction effect of drawing production and group assignment on creative potential was significant, while the interaction effect of drawing production and sex on creative potential turned out to be insignificant.
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Authors and Affiliations

Beata Mirucka
1
Monika Kisielewska
1

  1. Faculty of Education, University of Bialystok
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Abstract

The corrosion inhibition behaviour of 1-Ethyl-3-methylimidazolium-methanesulphonate (EMIM[MS]) and 1-Ethyl-3-methylimidazolium acetate (EMIM[Ac]) on API 5L X-52 carbon steel in 2 M HCl was investigated using weight loss, potentiodynamic polarization and electrochemical impedance methods. The corrosion rates of carbon steel decreased in the presence of these ionic liquids. The inhibition efficiencies of the compounds increased with concentration and showed a marginal decrease with a 10°C increase in temperature. Polarization studies showed the compounds to be mixed type inhibitors with stronger anodic character. The adsorption mechanism of both compounds on the metal surface was via physical adsorption and the process obeyed the El-Awardy kinetic-thermodynamic model. The associated activation energy of corrosion and other thermodynamic parameters were calculated to elaborate on the thermodynamics and mechanism of the corrosion inhibition process. EMIM[MS] was found to inhibit the corrosion of carbon steel better than EMIM[Ac] and is attributed to the presence of the highly electronegative sulphur atom in its structure and its larger molecular size.

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Authors and Affiliations

Magdalene Edet Ikpi
Okama Ebri Obono
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Abstract

The paper presents results of analysis of the influence of rotor construction on the steady-state torque-speed characteristics of a high-speed eddy-current brake. The investigation is carried out using two- and three-dimensional finite element models and measurements. A series of computations is carried out in order to find out the method for performance improvement of the considered system.
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Authors and Affiliations

Tomasz Garbiec
Marcin Kowol
Janusz Kołodziej
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Abstract

The development of a distributed generation will influence the structure of the power transmission and distribution network. Distributed sources have lower power and therefore the lines of lower voltage are used. Therefore, the electric field intensity near such lines is lower. On the other hand magnetic field intensity may prove essential. The main aim of the paper is to present a method estimating the “ballast” of the natural environment at 50 Hz electric and magnetic fields in the power system, with distributed and centralized generation in real operating conditions.

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Authors and Affiliations

Michał Zeńczak
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Abstract

Focus of the vibration expert community shifts more and more towards diagnosing machines subjected to varying rotational speeds and loads. Such machines require order analysis for proper fault detection and identification. In many cases phase markers (tachometers, encoders, etc) are used to help performing the resampling of the vibration signals to remove the speed fluctuations and smearing from the spectrum (order tracking). However, not all machines have the facility to install speed tracking sensors, due to design or cost reasons, and the signal itself has to then be used to extract this information. This paper is focused on the problem of speed tracking in wind turbines, which represent typical situations for speed and load variation. The basic design of a wind turbine is presented. Two main types of speed control i.e. stall and pitch control are presented,. The authors have investigated two methods of speed tracking, using information from the signal (without relying on a speed signal). One method is based on extracting a reference signal to use as a tachometer, while the other is phase-based (phase demodulation). Both methods are presented and applied to the vibration data from real wind turbines. The results are compared with each other and with the actual speed data.

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Authors and Affiliations

Jacek Urbanek
Tomasz Barszcz
Nader Sawalhi
Robert Randall

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