Spatial parallelization

As a consequence of this unfavorable scaling with N, applications of the AMD methods to date have involved at most a few thousand atoms, and have typically been much smaller than that. Since many processes of interest require larger system sizes to capture the essential physics, we are seeking ways to make larger AMD simulations feasible. One important step in this direction is our recent development of a spatially parallel TAD approach [34], which we describe very briefly here. 

Shim, Y., Amar, J.G., Uberuaga, B.P., Voter, A.F. Reaching extended length scales and time scales in atomistic simulations via spatially parallel temperature-accelerated dynamics. Phys. Rev. B 2007, 76, 205439-1-11. 

These two systems appear to operate in spatial parallelism and in temporal harmony. Although there are important differences in both the cortical sections and layers within sectors to which they project, there is also extensive overlap. Their strong interconnection at the level of the brain stem may well contribute to their temporal synchrony with the outputs of both cell groups being strongly correlated to the level of arousal and to receptivity to external stimuli. 

Pipeline architecture A computer architecture that employs time-sequential parallelism rather than spatial parallelism. That is, the input data is time sequenced, and each processor performs one portion of the total operation on each piece of data in time sequence. 

This idea is one of the most effective solutions to utilize multiple nanometric components without impairing the spatial parallelism or the superior speed of optical signals. The key to this idea is how to determine the arrangement of nanometric components that generates the intended optical near-field interactions. This can be achieved by precisely designing and fabricating nanostructures, such as shapes, layouts, compositions, and so on, that can induce arbitrary optical near-field interactions [21,22]. Moreover, protocols for the broadcast control and the narrowcast retrieval must be appropriately defined. 

The real-space sum is particularly easy to parallelize as it simply involves a spatial decomposition with appropriate attention to the overlap between adjacent regions due to the cut-off radius. Performance for the real-space contribution alone is given in Fig. 4. 

In order to improve parallelism and load balancing, a hybrid force-spatial decomposition scheme was adopted in NAMD 2. Rather than decomposing the nonbonded computation into regions of space or pairwise atomic interactions, the basic unit of work was chosen to be interactions between atoms... 

Clark, T., Hanxleden, R., McCammon, J., Scott, L. Parallelizing molecular dynamics using spatial decomposition. In Proceedings of the scalable high performance computing conference. May 23-25, 1994, Knoxville, Tennessee. IEEE Computer Society Press, Los Alamitos, California, 1994. 

HyperChem allows the visualization of two-dimensional contour plots for a certain number of variables, fh esc contour plots show the values of a spatial variable (a property f(x,y,z) in normal th rce-dimensional Cartesian space ) on a plane that is parallel to the screen. To obtain these contour plots the user needs to specify ... 

The E field lies parallel to the Aq veetor, and the H field is perpendieular to Aq both are perpendieular to the direetion of propagation of the light k/ k. E and H have the same phase beeause they both vary with time and spatial loeation as sin (cot - k r). The relative orientations of these veetors are shown below. 

Liquids are able to flow. Complicated stream patterns arise, dependent on geometric shape of the surrounding of the liquid and of the initial conditions. Physicists tend to simplify things by considering well-defined situations. What could be the simplest configurations where flow occurs Suppose we had two parallel plates and a liquid drop squeezed in between. Let us keep the lower plate at rest and move the upper plate at constant velocity in a parallel direction, so that the plate separation distance keeps constant. Near each of the plates, the velocities of the liquid and the plate are equal due to the friction between plate and liquid. Hence a velocity field that describes the stream builds up, (Fig. 15). In the simplest case the velocity is linear in the spatial coordinate perpendicular to the plates. It is a shear flow, as different planes of liquid slide over each other. This is true for a simple as well as for a complex fluid. But what will happen to the mesoscopic structure of a complex fluid How is it affected Is it destroyed or can it even be built up For a review of theories and experiments, see Ref. 122. Let us look into some recent works. 

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