Languages such as High Performance Fortran implement parallel algorithms by distributing large data structures across a multicomputer system. To enhance parallelism and reduce communication, it is sometimes bene cial for a programmer to change the distribution between phases of the algorithm. We introduce a new mapping strategy, called the spiral mapping, that reduces the communication overhead...

1. Introduction : Let there be a set of (empirically obtained) points Z= (z 1 , z 2 ,…,z n) : n ≥ 3 and any z i = (x i , y i). Let an inspection of the pattern that these points suggest or a conjecture regarding the law governing the generation of these points indicate that they resemble the trace (Buck, pp. 313-318) of a spiral. Then there may arise a need to investigate the law generating suc...

A high temperature superconductor (HTS) filter is designed and measured at 1.93 GHz, using microstrip half-wavelength spiral resonators. Resonant and coupling characteristics of miniaturized microstrip spiral resonators are investigated first. Then a 4-pole Chebyshev bandpass filter with a very narrow passband (4.1 MHz) is designed and realized using microstrip spiral resonators. The filter is ...

On-chip inductors are critical for enabling portable power-efficient wireless communication systems. Existing on-chip spiral inductors based on conventional planar integrated-circuit fabrication technology suffer from substrate loss and parasitics, and have relatively large footprints. In this paper, we discuss the development of two types of on-chip three-dimensional (3-D) inductors—a vertical...

The existence of spiral-type beams with a predetermined intensity distribution is investigated by theoretical and experimental means. Spiral-type beams with an intensity distribution in the form of an arbitrary planar line were found. A correspondence between these laser beams and a specific quantum-mechanical situation ground states of a charged particle in a uniform magnetic field was found. ...

We calculate the spectrum of collective excitations of the XY spiral state prepared adiabatically or suddenly from a uniform ferromagnetic F=1 condensate. For spiral wave vectors past a critical value, spin wave excitation energies become imaginary indicating a dynamical instability. We construct phase diagrams as functions of spiral wave vector and quadratic Zeeman energy.

We investigate the formation of substructure in spiral galaxies using global MHD simulations, including gas self-gravity. Local modeling by Kim and Ostriker (2002) previously showed that self-gravity and magnetic fields cause rapid growth of overdensities in spiral arms; differential compression of gas flowing through the arms then results in formation of sheared structures in the interarms. Th...

BACKGROUND Chronic otitis media (COM) can be treated with tympanoplasty with or without mastoidectomy. In patients who have undergone middle ear surgery, three-dimensional spiral computed tomography (CT) scan plays an important role in optimizing surgical planning. OBJECTIVES This study was performed to compare the findings of three-dimensional reconstructed spiral and conventional CT scan of...

We investigate the dynamics of magnetic fields in spiral galaxies by performing 3D Magnetohydrodynamics (MHD) simulations of galactic discs subject to a spiral potential using cold gas, warm gas and a two phase mixture of both. Recent hydrodynamic simulations have demonstrated the formation of inter-arm spurs as well as spiral arm molecular clouds provided the ISM model includes a cold HI phase...

PURPOSE To evaluate whether mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance (MR) imaging surpasses dual-phase spiral computed tomography (CT) in differentiating focal liver lesions. MATERIALS AND METHODS One hundred forty-five patients who had or were suspected of having focal liver lesions were included in a multicenter study and underwent dual-phase spiral CT and enhanced MR im...