Diffusion tensor imaging (DTI) MRI is a noninvasive imaging method of the cerebral tissues whose fibers directions are not evaluated correctly in the regions of the crossing fibers. For the same reason, the high angular resolution diffusion images (HARDI) are used for estimation of the fiber direction in each voxel. One of the main methods to specify the direction of fibers is usage of the spherical deconvolution. The spherical deconvolution is a method which is very sensitive to noise and creates negative values in the orientation distribution function (ODF) of the fiber. To solve this problem, methods such as Laplace-Beltrami regularized spherical deconvolution (LB-SD), the gradient based spherical deconvolution (GB-SD) and the constrained spherical deconvolution (CSD) are used. In this paper, the method for SD based on Wiener filter (WB-SD) is presented. Regarding the results, the direction of the crossing fibers is specified correctly. The proposed algorithm has specified the direction of the fibers as zero degree with 4.9 standard deviation and 89.9 degree with 3.6 standard deviation against two crossing fibers with 90 degree angle.

In conventional phased array systems, increasing the array length and consequently increasing the number of antenna elements are needed to improve spatial resolution. It can be addressed by MIMO radars using orthogonal signals from multiple transmitters and using the virtual array. Virtual element's locations are derived from the convolution of the physical element's location of the transmitter and receiver. To understand the functionality of MIMO radars, virtual array has been introduced. As the virtual array be larger, the radar angle resolution increase. Increasing the degree of freedom of the virtual array is highly dependent on the array of transmitter and receiver elements placement. The Nested Array which is one of the well-known methods in alignment of MIMO radar array elements, is investigated. In this article, the new nested array is examined and implemented in one dimension. The very innovative idea of this article is to use the new 2D nested array. A multi-step approach for implementing two-dimensional arrays using a new nested array for a MIMO radar is presented which can be generalized to any other structure with different number of elements. Finally, the advantages of the proposed method in terms of angular beam width of the main radar are presented. The results show that the proposed method is much more efficient than the other methods. The comparative results presented at the end of this article shows that the half-power beam width of the proposed method is approximately 0. 3 degrees while this value for the nested method is more than 2 degrees.

angular deformities of the lower limbs are common during childhood. In most cases this represents a variation in the normal growth pattern and is an entirely benign condition. Presence of symmetrical deformities and absence of symptoms, joint stiffness, systemic disorders or syndromes indicates a benign condition with excellent long-term outcome. In contrast, deformities which are asymmetrical and associated with pain, joint stiffness, systemic disorders or syndromes may indicate a serious underlying cause and require treatment.Little is known about the relationship between sport participation and body adaptations during growth. Intense soccer participation increases the degree of genu varum in males from the age of 16. Since, according to some investigations, genu varum predisposes individuals to more injuries, efforts to reduce the development of genu varum in soccer players are warranted. In this article major topics of angular deformities of the knees in pediatric population are practically reviewed.

Equal channel angular extrusion (ECAE) is one of the most powerful processes for manufacturing microstructure and nanostructure materials. This process is a kind of severe plastic deformation technique, which requires large extrusion force. In this study, the numerical and experimental investigation of extrusion force in ultrasonic assisted equal channel angular extrusion process (UAECAE) is carried out. ABAQUS Software is used for 2D finite element analysis of the process considering superimposed ultrasonic vibrations to the round billet work material. Experimentally, the conventional and ultrasonic assisted ECAE are performed with copper material to validate simulation results. The reduction in extrusion forceis observed due to ultrasonic vibrations. In order to achieve more average force reduction, it is recommended that the extrusion speed decreases and (or) vibrations amplitude increases. Stress and strain distributions are numerically investigated in various vibrational conditions and die angles. The best die angle to obtain optimum force reduction is 120º. In other die angles, vibrations amplitudes of 15μmand higher is necessary. Ultrasonic vibrations lead to oscillatory stresses with reduced average value, but do not influence the amount of plastic strain distribution. Achieving the beneficial products in ECAE requires heavy special equipment, whereas using UAECAE will leadto more accessible equipment. Finally, some optimal process parameters such as die angle, vibrations amplitude, for the proper application of these vibrations are proposed.