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W. Jendernalik, J. Jakusz, G. Blakiewicz, R. Piotrowski and S. Szczepański

CMOS realisation of analogue processor for early vision processing

The architecture concept of a high-speed low-power analogue vision chip, which performs low-level real-time image algorithms is presented. The proof-of-concept prototype vision chip containing 32 × 32 photosensor array and 32 analogue processors is fabricated using a 0.35 μm CMOS technology. The prototype can be configured to register and process images with very high speed, reaching 2000 frames per second, or achieve very low power consumption, several μW. Finally, the experimental results are presented and discussed.

Open access

R. Piotrowski and A. Szychowski

Abstract

The study presents the results of theoretical investigations into lateral torsional buckling (LTB) of bi-symmetric I-beams, elastically restrained against warping at supports. Beam loading schemes commonly used in practice are taken into account. The whole range of stiffness of the support joints, from free warping to warping fully restrained, is considered. To determine the critical moment, the energy method is used. The function of the beam twist angle is described with power polynomials that have simple physical interpretation. Computer programs written in symbolic language for numerical analysis are developed. General approximation formulas are devised. Detailed calculations are performed for beams with end-plate joints. Critical moments determined with programs and approximation formulas are compared with the results obtained by other researchers and with those produced by FEM. Very good accuracy of results is obtained.

Open access

Tomasz Karol Nowak, Kazimierz Duzinkiewicz and Robert Piotrowski

Abstract

This paper presents results concerning solutions of the fractional neutron point kinetics model for a nuclear reactor. Proposed model consists of a bilinear system of fractional and ordinary differential equations. Three methods to solve the model are presented and compared. The first one entails application of discrete Grünwald-Letnikov definition of the fractional derivative in the model. Second involves building an analog scheme in the FOMCON Toolbox in MATLAB environment. Third is the method proposed by Edwards. The impact of selected parameters on the model’s response was examined. The results for typical input were discussed and compared.

Open access

Mariusz Czapliński, Paweł Sokólski, Kazimierz Duzinkiewicz, Robert Piotrowski and Tomasz Rutkowski

Abstract

The pressurizer water level control system in nuclear power plant with pressurized water reactor (PWR) is responsible for coolant mass balance. The main control goal is to stabilize the water level at a reference value and to suppress the effect of time-varying disturbances (e.g. coolant leakage in primary circuit pipeline system). In the process of PWR power plant operation incorrect water level may disturb pressure control or may cause damage to electric heaters which could threaten plant security and stability. In modern reactors standard PID controllers are used to control water level in a pressurizer. This paper describes the performance of state feedback integral controller (SFIC) with reduced-order Luenberger state observer designed for water level control in a pressurizer and compares it to the standard PID controller. All steps from modeling of a pressurizer through control design to implementation and simulation testing in Matlab/Simulink environment are detailed in the paper.

Open access

Konrad Educational Research Institute, Warsaw, Poland, Radosław Kaczan and Małgorzata Rękosiewicz

Abstract

One of the important determinants of development during the transition to adulthood is the undertaking of social roles characteristic of adults, also in the area of finishing formal education, which usually coincides with beginning fulltime employment. In the study discussed in this paper, it has been hypothesized that continuing full-time education above the age of 26, a phenomenon rarely observed in Poland, can be considered as an unpunctual event that may be connected with difficulties in the process of identity formation. Relationships between identity dimensions and identity statuses, and age and educational context were analyzed. 693 individuals aged 19-35 took part in the study. The participants attended three types of educational institutions: (1) full-time university studies (BA or MA level), (2) part-time university studies (BA or MA level), and (3) full-time post-secondary school (certificate courses such as: medical rescue, massage therapy, cosmetology, occupational therapy). Among the students of full-time university studies predictable dependencies, also in respect of highlevels of indicators of identity crisis and a high frequency of diffused identity occurrence, were observed. Such dependencies were not found in the group of full-time post-secondary school students.

Open access

Z. Kowal, M. Siedlecka, R. Piotrowski, K. Brzezińska, K. Otwinowska and A. Szychowski

Abstract

The study presents the summary of the knowledge of energy-active segments of steel buildings adapted to obtain electrical energy (EE) and thermal energy (TE) from solar radiation, and to transport and store TE. The study shows a general concept of the design of energy-active segments, which are separated from conventional segments in the way that allows the equipment installation and replacement. Exemplary solutions for the design of energy-active segments, optimised with respect to the principle of minimum thermal strain and maximum structural capacity and reliability were given [34]. The following options of the building covers were considered: 1) regular structure, 2) reduced structure, 3) basket structure, 4) structure with a tie, high-pitched to allow snow sliding down the roof to enhance TE and EE obtainment. The essential task described in the study is the optimal adaptation of energy-active segments in large-volume buildings for extraction, transportation and storage of energy from solar radiation.