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The turbulent structures in the wake (x/d =10 to 60) of a screen cylinder have been educed to understand the roles of the various structures as evolving downstream by comparing with those obtained in a solid circular cylinder wake at Reynolds number, Re of 7000. Using a wavelet multiresolution technique, the flow structures are decomposed into a number of wavelet components based on their central frequencies. It is observed that in the solid cylinder wake, large-scale structures (of frequencyf0 and 1.2 f0) make the largest contribution to the Reynolds stresses although they start to lose their roles significantly at x/d> 20. In the screen cylinder wake, the intermediate-scale structures (2f0 and 4f0) contribute the most to the Reynolds stresses atx/d =10 before being taken over by the large-scale structures (f0) further downstream., {"references":["R. D. Blevins, Flow-induced vibration, 2nd ed. New York: Van Nostrand Reinhold, 1990.","P. Price, \"Suppression of the flow-induced vibration of circular cylinders,\" J. Eng. Mech. Div., Am. Soc. Civ. Eng., vol. 82, 1956.","M. M. Zdravkovich and J. R. Volk, \"Effect of shroud geometry on pressure distributed around a circular cylinder,\" Journal of Sound and Vibration, vol. 20, pp. 451-455, 1972.","A. M. Azmi, T. Zhou, H. Wang, L. P. Chua, and L. Cheng, \"On the effectiveness and mechanism of vortex induced vibration suppression using a screen cylinder,\" in Twenty-second (2012) International Offshore and Polar Engineering Conference, Rhodes, Greece, 2012, pp. 586-594.","M. Farge, \"Wavelet Transforms and Their Applications to Turbulence,\" Annual Review of Fluid Mechanics, vol. 24, pp. 395-457, 1992.","M. Farge and G. Rabreau, \"Wavelet Transform to Detect and Analyze Coherent Structures in Two-Dimensional Turbulent Flows,\" Comptes Rendus De L Academie Des Sciences Serie Ii, vol. 307, pp. 1479-1486, Oct 30 1988.","C. Meneveau, \"Analysis of Turbulence in the Orthonormal Wavelet Representation,\" Journal of Fluid Mechanics, vol. 232, pp. 469-520, Nov 1991.","A. Rinoshika and Y. Zhou, \"Orthogonal wavelet multi-resolution analysis of a turbulent cylinder wake,\" Journal of Fluid Mechanics, vol. 524, pp. 229-248, Feb 10 2005.","H. Li and Y. Zhou, \"Comparison between triangular cylinder and screen near-wakes in the orthogonal wavelet representation,\" Jsme International Journal Series B-Fluids and Thermal Engineering, vol. 46, pp. 366-376, Aug 2003.\n[10]\tA. Rinoshika and Y. Zhou, \"Effects of initial conditions on a wavelet-decomposed turbulent near-wake,\" Physical Review E, vol. 71, Apr 2005.\n[11]\tA. Rinoshika and Y. Zhou, \"Effects of initial conditions on wavelet-decomposed structures in a turbulent far-wake,\" International Journal of Heat and Fluid Flow, vol. 28, pp. 948-962, 2007.\n[12]\tS. F. M. Razali, T. Zhou, A. Rinoshika, and L. Cheng, \"Wavelet analysis of the turbulent wake generated by an inclined circular cylinder,\" Journal of Turbulence, vol. 11, pp. 1-25, May 11 2010.\n[13]\tI. Daubechies, \"Ten lectures on wavelets,\" 1992.\n[14]\tY. Zhou and R. A. Antonia, \"Critical-Points in a Turbulent near Wake,\" Journal of Fluid Mechanics, vol. 275, pp. 59-81, Sep 25 1994.\n[15]\tY. Zhou and R. A. Antonia, \"Memory effects in a turbulent plane wake,\" Experiments in Fluids, vol. 19, pp. 112-120, Jun 1995.\n[16]\tY. Zhou and R. A. Antonia, \"A Study of Turbulent Vortices in the near Wake of a Cylinder,\" Journal of Fluid Mechanics, vol. 253, pp. 643-661, Aug 1993."]}