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This article discusses an adaptive filtering technique for reducing speckle using second order statistics of the speckle pattern in ultrasound medical images. Several region-based adaptive filter techniques have been developed for speckle noise suppression, but there are no specific criteria for selecting the region growing size in the post processing of the filter. The size appropriate for one local region may not be appropriate for other regions. Selection of the correct region size involves a trade-off between speckle reduction and edge preservation. Generally, a large region size is used to smooth speckle and a small size to preserve the edges into an image. In this paper, a smoothing procedure combines the first order statistics of speckle for the homogeneity test and second order statistics for selection of filters and desired region growth. Grey level co-occurrence matrix (GLCM) is calculated for every region during the region contraction and region growing for second order statistics. Further, these GLCM features determine the appropriate filter for the region smoothing. The performance of this approach is compared with the aggressive region-growing filter (ARGF) using edge preservation and speckle reduction tests. The processed image results show that the proposed method effectively reduces speckle noise and preserves edge details.

The Recurrence plots (RPs) have been introduced in several different scientific and medical disciplines. The main purpose of recurrence plot is used to of identify the higher dimensional phase space trajectories. RPs are purely graphically representation which have been designed for the detection of hidden dynamical patterns and non-linearity present in the data, the evaluation of error which is caused by observational noise can be done by Recurrence Quantification Analysis (RQA). RQA method is initially used to minimize the error present in the given signals. RQA method is a basically a technique for the analysis of nonlinear data to quantify the number and duration of a dynamical systems. The recurrence plot is used for time series domain for multidimensional signal also. Recurrence is the property of non-stationary and dynamical system to characteristics the time series analysis in phase space trajectories. Recurrence Quantification Analysis is used to derive from recurrence plots, which are based upon distances matrices of time series.

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This work presents optical simulations that are used to design a betatron driven by a short-pulse laser based on the Laser Wakefield Acceleration (LWFA) concept. These simulations explore how the optical setup and its components influence the performance of the betatron. The impact of phase irregularities induced by optical elements is investigated. In order to obtain a good estimate of the future performance of this design a combination of two distinct techniques are used -Field Tracing for optical simulations employing a combination of the Zemax and VirtualLab computational platforms for the laser beam propagation and focusing with the given optical system and particle-in-cell simulation (PIC) for simulating the short-pulse laser interaction with a gas target. The result of the optical simulations serves as an input for the PIC simulations. Application of Field Tracing in combination with the PIC for the purposes of high power laser facility introduces the new application for VirtualLab Fusion. Based on the result of these simulations an alternative design with a hole in the final folding mirror coupled with a spherical focusing mirror is considered in favour of more commonly used off-axis parabola focusing setup. Results are demonstrating, that the decrease of the irradiance due to the presence of the central hole in the folding mirror is negligible (9.69 × 10 19 W/cm 2 for the case without the hole vs. 9.73 × 10 19 W/cm 2 for the case with hole). However, decrease caused by the surface irregularities (surface RMS λ/4, λ/20 and λ/40) is more significant and leads to the poor performance of particle production. K: Accelerator modelling and simulations (multi-particle dynamics; single-particle dynamics); Beam Optics 1Corresponding author.