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The use the of digital image correlation in a strain analysis

References Bruck H.A., McNeill S.R., Sutton M.A. and Peters W.H. (1989): Digital image correlation using Newton-Raphson method of partial differential correction. - Experimental Mechanics, vol.29(3), pp.261-267. Chu T.C., Ranson W.F., Sutton M.A. and Peters W.H. (1985): Applications of digital image correlation techniques to experimental mechanics. - Experimental Mechanics, vol.25, pp.232-244. Dantec Dynamics. Digital Imagine Correlation System (Q-400). www.dantecdynamics.com Kostka J. (2012

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The Use of Optical Methods in the Analysis of the Areas with Stress Concentration

Mechanically Fastened Joints. Engineering 2012 (4), 359 – 367. [5] M. Fernández. Metrological Study for the Optimal Selection of the Photoelastic Model in Transmission Photoelasticity. Applied Optics 2011 (50), No. 29, 5721 – 5727. [6] M. Pástor, F. Trebuňa. Application of Transmission Photoelasticimetry for Stress Concentration Analyses in Construction Supporting Parts. Applied Mechanics and Materials 2014 (611), 443 – 449. [7] A. Mudassar, S. Butt. Improved Digital Image Correlation for In-plane Displacement Measurement. Applied Optics 2014

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An overview of Millionschikov's quasi-normality hypothesis applied to turbulence

of the zero-fourth-cumulant approximation in the decay of isotropic turbulence. - Journal of Fluid Mechanics, vol.16, pp.33-40. Panchev S. (1971): Random functions and turbulence. - Oxford: Pergamon Press., p.444. Proudman I. and Reid W.H. (1954): On the decay of a normally distributed and homogeneous turbulent velocity field. - Phil. Trans. Roy. Soc. vol.247A, p.163-189. Uberoi M.S. (1953): Quadruple velocity correlations and pressure fluctuations in isotropic turbulence. - J. Aeronaut. Sci., vol.20, p.197.

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Study of the influence of temperature and water level of the reservoir about the displacement of a concrete dam

. – Philos. Trans. R. Soc. A, vol.365, pp.303–315. [10] Figueiredo E., Park G., Farrar C.R., Worden K. and Figueiras J. (2011): Machine learning algorithms for damage detection under operational and environmental variability . – Struct. Health Monit, vol.10, pp.559–572. [11] Buzzi M.F. (2007): Evaluation of time-series correlations readings of geotechnical and structural monitoring instruments and environmental variables in dams - Itaipu case study . - Masters dissertation, UFPR. (In Portuguese) [12] Guedes Q.M. and De Faria É.F. (2007): Statistical

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Robust Optical Flow Estimation Applied to Particle Image Velocimetry Images for High Resolution Velocity Measurements

References [1] Anderson, J. D., Fundamentals of Aerodynamics , McGraw-Hill’s, New York 2004. [2] Billy, F., David, L., Pineau, G., Single pixel resolution correlation applied to unsteady flow measurements , Measurement Science and Technology, Vol. 15, pp. 1039-1045, 2004. [3] Black, M. J., Anandan, P., A framework for the robust estimation of optical Flow , Fourth International Conf. on Computer Vision, ICCV-93, Berlin 1993. [4] Black, M. J., Anandan, P., The robust estimation of multiple motions: parametric and piecewise-smooth flow

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Use of 3D Printing Technology in the Aviation Industry on an Example of Numerical Experimental Stress State Analysis of Unmanned Aerial Vehicle Wing

] Stava, O., Vanek, J., Benes, B., Carr, N., Mech, R., Stress Relief – Improving Structural Strength of 3D Printable Objects, 2012. [7] Szmidt, A., Rębosz-Kurdek, A., New approaches of improving FDM/FFF printing techology , Mechanik, 3, pp. 258-261, 2017. [8] Vaezi, M., Chua, C. K., Effects of layer thickness and binder saturation level parameters on 3d printing process , The International Journal of Advanced Manufacturing Technology, Vol. 53, Iss. 1, pp 275-284, 2011. [9] Zafar, A., Digital image correlation , CEE 498KUC – Experimental methods in

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Properties of AlMg3 Aluminium Alloy Joints Welded by Electron Beam Melting

References [1] Klimpel, A., Technologia spawania i cięcia metali , Wyd. Politechniki Śląskiej, Gliwice 1997. [2] Grodzinski, A., Czopik, A., The application of electron beam joining for vacuum parts, Elektronika, XXXIX, 5, p. 5, 1998. [3] Wójcicki, S., The correlation between operating parameters of electron beam welding machine WS – 15 KW/100 kv and quality of welds , Elektronika, XXXVIII, 3, p. 30, 1997.

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Numerical Prediction of GTD-350 Turboshaft Engine Combustor Deterioration

Abstract

The aim of this article is to describe the use of Computational Fluid Dynamics (CFD) model for turboshaft combustor chamber deterioration analysis. To show advantages of the proposed approach the test bench of GTD-350 turboshaft engine operating at the Institute of Heat Engineering, Warsaw University of Technology was used as an example. The CFD modelling of the reactive flow inside 40º sector of GTD-350 engine section was developed. Proposed modelling technique provides good correlations with experimental data and shows that the combustor front wall soot accumulation is clearly related to the fuel droplets residence time and the oxygen mass fraction. The temperature distribution inside the combustion chamber allows concluding on possible hot distress areas on the combustion chamber liner walls. Engine borescope inspection (BSI) of the compressor, combustion chamber, compressor turbine and power turbine is used to correlate model predictions with a real GTD-350 engine deterioration. Very good correlation of the engine BSI observations with the numerical predictions proves usefulness of the developed model. Finally, advantages and future applications of the developed model are discussed.

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Evaluation Of Air Pollution Measurements In Urban Environment Considering Traffic Intensity

Abstract

This paper presents the analysis of air pollution monitoring and evaluation results in the center of Riga City. The air quality reports have pointed out that road traffic and road infrastructure are the main issues of air pollution in the center of Riga. However, none of the reports validated this assumption considering actual traffic flow data. In the present article, the air pollution data have been collected and analyzed in the context with traffic flow. The statistical analysis of both the air pollution and traffic flow data was performed and the correlation between them was established and evaluated. Finally, the conclusions and recommendations for further improvements of the methodology of measurements necessary for successful air quality assessment in the urban areas and particularly in Riga city are given.

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Moisture Effect on the Ultrasonic Pulse Velocity in Concrete Cured under Normal Conditions and at Elevated Temperature

Abstract

The ultrasonic pulse velocity (UPV) in water-saturated concrete is higher than in dry concrete. However, moisture influence on the UPV is defined within a wide range: - from negligible to quite significant (16 per cent). The nature of "UPV − concrete moisture" correlation is also interpreted in different ways - both as linear and as exponential. This paper reviews how various degrees of moisture saturation influence the UPV in concrete when sounding is carried out by the frequently used ultrasonic testing method - the indirect transmission by using longitudinal wave pulse. Research was conducted on specimens hardened both under standard conditions and at elevated temperatures. The results show a sudden UPV increase at the degree when the maximum water absorption in concrete is achieved.

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