The mode-matching applications to scattering from circular and annular apertures in a thick perfectly conducting plane are reviewed. The Hankel and Weber transforms are utilized to solve the boundary-value problems of circular and annular apertures. Simple electrostatic problems are presented to illustrate the mode-matching method in terms of the Hankel and Weber transforms. Various types of We...

Annular patterns with a high degree of zonal symmetry play a prominent role in the natural variability of the atmospheric circulation and its response to external forcing. But despite their apparent importance for understanding climate variability, the processes that give rise to their marked zonally symmetric components remain largely unclear. Here the authors use simple stochastic models in c...

This paper presents modeling of annular patch antenna. The S and Z parameters of an Annularpatch Microstrip antenna are investigated and optimization. The optimization is performed byvarying the inner and outer radius of annular Ring. The impedance and radiation characteristicsof annular patch antenna are examined and compared. It is able to achieve a return loss lessthan -36 dB...

OBJECTIVES Annular pancreas is a rare congenital anomaly characterized by pancreatic tissues wrapping completely or incompletely around the descending duodenum. In most patients with annular pancreas, onset occurs in early childhood. Adults with annular pancreas are prone to duodenal ulcers and pancreatitis. Intraductal papillary mucinous neoplasm (IPMN) is a type of papillary mucinous secretor...

in this paper, a nonlinear free vibration analysis of thin annular functionally graded (fg) plate integrated with two uniformly distributed actuator layers made of piezoelectric (pzt4) material on the top and bottom surfaces of the annular fg plate is presented based on kirchhoff plate theory. the material properties of the fgm core plate are assumed to be graded in the thickness direction acco...

introduction: topographic anatomy of the tendons and ligaments in healthy cases provides a normal atlas to diagnose abnormalities. the aim of this study was to provide ultrasonography description of the palmar tendons and ligaments of the anatoly donkey. methods: the metacarpal regions of 6 healthy anatoly donkeys were prepared for ultrasonography and divided to 6 levels (1a, 1b, 2a, 2b, 3a, 3b...

In this paper, the exact analytical and numerical solutions for rotating variable-thickness annular disk are presented. The inner and outer edges of the rotating variable-thickness annular disk are considered to have free boundary conditions. Two different annular disks for the radially varying thickness are given. The numerical Runge-Kutta solution as well as the exact analytical solution is a...

Both clinical and pathologic findings must be considered when diagnosing figurate skin lesions, which are often seen in routine practice. Although a skin biopsy may sometimes be diagnostic, more often the information provided is nonspecific. In an attempt to offer an approach to diagnosing these dermatoses, we have classified annular lesions according to the presence of lymphocytic, neutrophili...

BACKGROUND Little is known about the impact of tricuspid annuloplasty (TAP) on annular dynamics. We assessed tricuspid annular dynamics using 3-D transesophageal echocardiography (3D-TEE) before and after TAP with different types of prosthetic ring. METHODS AND RESULTS 3D-TEE of the tricuspid valve was acquired in 30 patients (TAP with rigid ring [RR], n=8; TAP with flexible ring [FR], n=10; ...