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References [1] Cannon R. H., Dynamika układów fizycznych, WNT, Warszawa 1973 [Dynamics of physical systems - avaliable in Polish]. [2] Cwalina A., Zacharewicz M., Research on energetic processes in a marine diesel engine driving a synchronous generator for diagnostic purposes, Part 1, Physical model of the processes, ‘Journal of Polish CIMAC’, 2013, Vol. 8, No. 1, pp. 97-104. [3] Dzetsina O., Gladushin V., Method of diagnostics of locomotive diesel engine, ‘ТEKA Komisji Motoryzacji i Energetyki Rolnictwa’ [‘TEKA Commission of Motorization and Power Industry in

Abstract

As the number of indoor swimming pools and wellness centers are currently growing, it is necessary to concentrate on the parameters of indoor environments. These parameters are necessary for the design of the HVAC systems that operate these premises. In indoor swimming-pool facilities, the energy demand is large due to ventilation losses from exhaust air. Since water evaporates from a pool’s surface, exhaust air has a high water content and specific enthalpy. In this paper the results of the water evaporation rate measured from swimming pool surfaces at higher thermal water temperatures are described.

Echosounder. Acta Physica Polonica A., 2013,Vol. 123, No.6 , pp. 1094-1097. 10. Ghionna, V.N., Jamiolkowski, M. : A critical appraisal of calibration chamber testing in sands. Proceedings of the 1st International Conference on Calibration Chamber Testing, Clarkson Univ., Potsdam, USA, 1991. Edited by A.-B. Huang, pp. 13-37. 11. Dijkstra, J., Gaudin, C., & White, D. J. : Comparison of failure modes below footings on carbonate and silica sands. International Journal of Physical Modelling in Geotechnics , 2013, 13 (1). 12. Hazarika, H., Kohama, E. and Sugano, T.: Underwater

physical modeling, Proceedings of the Conference on Digital Audio Effects (DAFx) 04 , Naples, Italy, pp. 101-106. Ochs K. (2001). Passive integration methods: Fundamental theory, International Journal of Electronic Communication (AEÜ) 55 (3): 153-163. Petrausch S. and Rabenstein R. (2004). A simplified design of multidimensional transfer function models, Proceedings of the International Workshop on Spectral Methods and Multirate Signal Processing (SMMSP2004) , Vienna, Austria, pp. 35-40. Petrausch S. and Rabenstein R. (2005a). Application of block based physical

Abstract

Rapid firing of two bullets from the Skorpion submachine gun vz. 61 cal. 7,65 mm towards the target located at a distance of 25 [m] was registered at a police shooting range. The tests confirmed the opinion of the users regarding the presence of significant weapon dispersion. This undesirable effect prompted the authors to undertake work in order to improve the dynamic properties of weapons. Experimental studies provided information on the kinematics of movement of human - weapon system. On the basis of the courses of variation of displacement, velocity and acceleration over time, the behaviour of a machine gun in thirteen characteristic points of its operation was specified. The verification of bullet holes and analysis of recorded images showed a slight deviation of movement of the objects under examination from the vertical plane. Therefore, a physical model of human - weapon system with five degrees of freedom in the vertical plane was formulated. On the basis of the physical model, a mathematical model of human - weapon system was derived, which can be classified as linear, determined, variable over time, dissipative and constrained.

Abstract

For technical applications, a physical model capable of predicting the particle evolution in the burning process along its trajectory through the furnace is very useful. There are two major demands: all the thermo-dynamic processes that describe the particle burning process must be accounted and the model must be written in such equation terms to allow the intervention for parameter settings and particle definition. The computations were performed for the following parameters: furnace average temperature between 700 and 1200 °C, size of the sawdust particle from 4 to 6 mm and fix carbon ignition between 500 and 900 °C. The values obtained for the characteristic parameters of the burning process ranged from 30 to 60 [kg/(h·m3)] for the gravimetrical burning speed WGh and from 150 to 280 [kW/m3] for the volumetric thermal load of the furnace QV. The main conclusion was that the calculus results are in good agreement with the experimental data from the pilot installations and the real-case measurements in the sawdust working boiler furnaces or pre-burning chambers. Another very important conclusion is that the process speed variation, when the furnace temperature changes, confirms the thermo-kinetic predictions, namely that the burning process speed decreases when the furnace temperature increases.

Abstract

The construction of a water intake along the wharf shoreline can realise the intensive and comprehensive utilisation of the shoreline. However, since the water intake will increase the lateral flow at the wharf and also the hydrodynamic forces on ships, it will bring risks to ships mooring and leaving. The effects of the water intake on ships are studied using a physical model, numerical model and standard formulas. The results show that it leads to an increase of the hydrodynamic forces acting on the ship when the standard formulas are used to calculate the forces without considering the water level difference between the two sides of the ship. The results of the physical model are closer to the real situation. Measures that can effectively reduce the influence of the water intake on ships are proposed by increasing the distance between the wharf front and the front of the water intake as well as the depth of the water inlet windows.

Abstract

There are currently several national standards or regulations for the design of the piled embankment, providing suitable solutions for foundation of transport structure on soft, high compressible subsoil, [1]. The most widely used and the best-known standard is British Standard BS8006 [2], which was confronted with another analytical design methodologies (Ebgeo, CUR). Today’s popularity and versatility of FEM numerical models brings many advantages, which analytical methods cannot achieved, but must be verified by proposed scaled physical model, which was currently being developed by Department of Geotechnics, University of Žilina.

Abstract

This article presents partial results of the laboratory development of an anaerobic bioreactor designed for the physical modelling of (semi)continuous dry or wet anaerobic digestion processes. A horizontal cylindrical tank reactor of 0.4 m3 total capacity has been developed. The reactor allows the continuous stirring of a liquid batch or the intermittent stirring of a solid batch. The bioreactor has been used as a lab-scale digestor in the research project dealing with high-solids (dry) anaerobic co-digestion organic fraction of mixed municipal solid waste. The first experiment was performed on the mixture of MSW with corn silage (1:1) with the weight of 300 kg.

Abstract

A suspension bridge is the most suitable type for a long-span bridge. Increased kinematic displacements are the major disadvantages of suspension bridges. This problem can be solved by application of prestressed cable truss.

Dynamic approach is one of regulated bridge design parts. Determination of natural frequencies of a physical model of a prestressed suspension bridge is presented in this paper.

Natural frequencies, as mode shapes, of the model depending on a prestressing level were determined. It was shown that a mode shape with one half wave did not appear.

Experiments showed that dynamic characteristics of prestressed suspension bridge could be regulated by changing a prestressing level, which excludeda possibility of resonance appearance.