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Jaime G. Cuevas, José L. Arumí and José Dörner

., 42, 262–281. Dörner, J., Huertas, J., Cuevas, J.G., Leiva, C., Paulino, L., Arumí, J.L., 2015. Water content dynamics in a volcanic ash soil slope in southern Chile. J. Plant Nutr. Soil Sci., 178, 4, 693–702. Edwards, R.T., 1998. The hyporheic zone. In: Naiman, R.J., Bilby, R.E. (Eds.): River Ecology and Management, Lessons from the Pacific Coastal Ecoregion. Springer, New York, USA, Chapter 16, pp. 399–429. Folmar, N.D., Miller, A.C., 2008. Development of an empirical lag time equation. J. Irrig. Drain. E. ASCE, 134, 4, 501–506. Giandotti

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Joanna Marszałek and Władysław Kamiński

.1016/S0376-7388(01)00457-4. Schaetzel P., Catherine Vauclair C., Nguyen Q. T., Bouzerar R., 2004. A simplified solution-diffusion theory in pervaporation: the total solvent volume fraction model. J. Membr. Sci. , 244, 117-127. DOI: 10.1016/j.memsci.2004.06.060. Stachecka A., 2005. Empirical and the semi-empirical models of alcohols dehydration by pervaporation, PhD thesis, Technical University of Lodz, Poland. Trifunovic O., Trägårdh G., 2002. Transport of diluted volatile organic compounds

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Andrzej Sawicki, Justyna Sławińska and Jacek Mierczyński

References [1] ATKINSON J.H., An Introduction to the Mechanics of Soil and Foundations , McGraw-Hill, London 1993. [2] BAZANT Z.P., KRIZEK R.J., Endochronic constitutive law for liquefaction with cyclic loads , Proc. ASCE, J. Engrg. Mech. Div., 1976, 102, EM2, 225-238. [3] GUDEHUS G., A comprehensive constitutive equation for granular materials, Soils and Foundations , 1996, 36, No. 1, 1-12. [4] KOLYMBAS D., Introduction to Hypoplasticity, Advances in Geotechnical Engineering and Tunnelling , Balkema, Rotterdam/ Brookfield 2000. [5] SAADA A

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M. Ślęzak

Abstract

The objective of this article is to review models for calculating the value of liquid dynamic viscosity. Issues of viscosity and rheological properties of liquid ferrous solutions are important from the perspective of modelling, along with the control of actual production processes related to the manufacturing of metals, including iron and steel. Conducted analysis within literature indicates that there are many theoretical considerations concerning the effect of viscosity of liquid metals solutions. The vast majority of models constitute a group of theoretical or semi-empirical equations, where thermodynamic parameters of solutions, or some parameters determined by experimental methods, are used for calculations of the dynamic viscosity coefficient.

This article presents equations belonging to four groups of models for calculating the value of the dynamic viscosity coefficient: rheological models, non-rheological models, non-rheological and rheological models for calculating viscosity of metals. The last group of equations is developed by own experiments – high temperature rheological liquid steel measurements.

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Grzegorz Szapajko and Henryk Rusinowski

Mathematical modelling of steam-water cycle with auxiliary empirical functions application

Research oriented on identification of operating states variations with the application of mathematical models of thermal processes has been developed in the field of energy processes diagnostics. Simple models, characterised by short calculation time, are necessary for thermal diagnostics needs. Such models can be obtained using empirical modelling methods. Good results brings the construction of analytical model with auxiliary empirical built-in functions. The paper presents a mathematical model of a steam-water cycle containing mass and energy balances and semiempirical models of steam expansion line in turbine as well as heat transfer in exchangers. A model of steam expansion line in a turbine is worked out with the application of a steam flow capacity equation and an internal efficiency of process equation for each group of stages for the analysed turbine. A model of a heat exchanger contains energy balance and the relation describing heat transfer in an exchanger, proposed by Beckman. Estimation of empirical equations coefficients was realised with the application of special and reliable measurements. Estimation criterion was a weighted relative sum of the remainder squares. There are exemplary calculations results presented in the final part of paper.

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Rafał Bryk, Holger Schmidt, Thomas Mull, Thomas Wagner, Ingo Ganzmann and Oliver Herbst

-556. [18] Bergles A.E.: The determination of forced-convection surface boiling heat transfer. J. Heat Transfer 86(1964) 3, 365-372. [19] Churchill W., Chu H.H.S.: Correlation equations for laminar and turbulent free convection from a horizontal cylinder. Int. J. Heat Mass Tran. 18(1975), 1049-1053. [20] Mikielewicz D., Andrzejczyk R.: Comparative study of flow condensation in conventional and small diameter tubes. Arch. Thermodyn. 33(2012), 2, 67-83 DOI: 10.2478/v10173-012-0011-2

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S. Talukdar, Bimlesh Kumar and S. Dutta

Survey Professional Paper 422-I. BATHURST, J. C., GRAF W. H., CAO H. H., 1987: Bed load discharge equations for steep mountain rivers, in Sediment Transport in Gravel Bed Rivers, edited by C. R. Thorne, J. C. Bathurst, and R. D. Hey, pp. 453-491, John Wiley, New York. BHATTACHARYA B., PRICE R. K., SOLOMATINE D. P., 2007: A machine learning approach to modeling sediment transport. ASCE J. of Hydraulic Engineering, 133 , 4, 440-450. BEVEN, K. J. 2001: Rainfall-Runoff Modelling: The Primer

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Samuel N. A. Tagoe, Samuel Y. Mensah and John J. Fletcher

Abstract

Objectives: The present study aimed to generate intensity-modulated beams with compensators for a conventional telecobalt machine, based on dose distributions generated with a treatment planning system (TPS) performing forward planning, and cannot directly simulate a compensator.

Materials and Methods: The following materials were selected for compensator construction: Brass, Copper and Perspex (PMMA). Boluses with varying thicknesses across the surface of a tissue-equivalent phantom were used to achieve beam intensity modulations during treatment planning with the TPS. Beam data measured for specific treatment parameters in a full scatter water phantom with a 0.125 cc cylindrical ionization chamber, with a particular compensator material in the path of beams from the telecobalt machine, and that without the compensator but the heights of water above the detector adjusted to get the same detector readings as before, were used to develop and propose a semi-empirical equation for converting a bolus thickness to compensator material thickness, such that any point within the phantom would receive the planned dose. Once the dimensions of a compensator had been determined, the compensator was constructed using the cubic pile method. The treatment plans generated with the TPS were replicated on the telecobalt machine with a bolus within each beam represented with its corresponding compensator mounted on the accessory holder of the telecobalt machine.

Results: Dose distributions measured in the tissue-equivalent phantom with calibrated Gafchromic EBT2 films for compensators constructed based on the proposed approach, were comparable to those of the TPS with deviation less than or equal to ± 3% (mean of 2.29 ± 0.61%) of the measured doses, with resultant confidence limit value of 3.21. Conclusion: The use of the proposed approach for clinical application is recommended, and could facilitate the generation of intensity-modulated beams with limited resources using the missing tissue approach rendering encouraging results.

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Anatolij Budagovskyi and Viliam Novák

process. (In Russian with English summary.) Vodnyje resursy, 21 , 2, 133-143. BUDAGOVSKYI A.I., 1989: Semiempirical theory of transpiration and plant canopy water regime. (In Russian with English summary.) Vodnyje resursy, 2 , 5-17. BUDAGOVSKYI A.I., LOZINSKAYA E.A., 1996: Heat and water transport in a canopy. (In Russian with English summary.) Vodnyje resursy, 23 , 6, 658-667. BUDAGOVSKYI A.I., LOZINSKAYA E.A., 1997: The influence of geophysical and biophysical parameters on transpiration

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RW Dwyer, P Chen and RD Wasyk

-19. 8. Meyer-Abich, K.M.: Die Strómungsverhaltnisse in Cigaretten; Beitr. Tabakforsch. 3 (1966) 307-329. 9. Pitie, B.: Ventilation equations [in French]: Ann. du Tabac 18 (1981) 5-40. 10. Rasmussen, G.T. and L.W. Renfro: Simulated smoke testing of filter cigarettes under various smoking conditions; 51st Tobacco Chemists Research Conference, Winston-Salem, NC, Program Booklet and Abstracts, no. 6, p. 26, 1997. 11. Schneider, W. and A. Schulter: A semi-empirical model for simulating the effect