The solution of any such eigenvalue problem requires a number of computer operations that scales as the dimension of the F matrix to the third power. Since the indices on the F matrix label AOs, this means [Pg.2185]

There appears to be a world market for an infinite number of computers and otlier electronic devices. [Pg.2896]

The study of slow protein dynamics is a fascinating field with still many unknowns. We have presented a number of computational techniques that are currently being used to tackle those questions. Most promising for our case seems the development of methods that combine an implicit solvent description with techniques to induce conformational transitions. [Pg.76]

Since every processor computes the same number of computations, the [Pg.488]

Data visualization is the process of displaying information in any sort of pictorial or graphic representation. A number of computer programs are available to apply a colorization scheme to data or to work with three-dimensional representations. In recent years, this functionality has been incorporated in many [Pg.115]

Tinkler and Metzner (1961) executed a large number of computations for simultaneous equations by approximate and exact methods and presented their results on numerous graphs. One of those is shown in Figure 1.6.1. Please note that on this figure the parameter is e=y P De/at in the notation of this book, and the abscissa = is the Thiele modulus. [Pg.27]

No detailed structural studies have been carried out experimentally on T4 derivatives but a number of computational studies have been undertaken as part of the drive to understand the fundamental nature of silicate structures, many of which are made up of small polyhedral units. [Pg.6]

Organic molecules are the easiest to model and the easiest for which to obtain the most accurate results. This is so for a number of reasons. Since the amount of computational resources necessary to run an orbital-based calculation depends on the number of electrons, quantum mechanical calculations run fastest for compounds with few electrons. Organic molecules are also the most heavily studied and thus have the largest number of computational techniques available. [Pg.283]

Suppose one wanted to study a biological system, possibly as small as an amino acid or as big as a polypeptide or a small nucleotide strand. There are a number of computer programs equipped to handle such systems, including the Gaussian programs. [Pg.8]

In the early 1980s, the world witnessed the sale of the first personal computers. Its transition from the relatively bulky and slow first units to the sleek, speed demons has made the computer truly revolutionary. With each improvement in computers, however, comes the increasing problem of what to do with the ever increasing number of computer e-wastes. The U.S. EPA estimates that nearly 250 million computers will become obsolete in the next five years in the United States alone. Unfortunately, only approximately 10% of these old computers that are retired each year are being recycled. This presents a substantial concern because toxic elements such as lead, cadmium, mercury, barium, chromium, beryllium as well as flame retardant, and phosphor are contained in a typical computer and there would be potential harm if there was a release of these elements into the environment.1 [Pg.1230]

A complete model for the description of plasma deposition of a-Si H should include the kinetic properties of ion, electron, and neutral fluxes towards the substrate and walls. The particle-in-cell/Monte Carlo (PIC/MC) model is known to provide a suitable way to study the electron and ion kinetics. Essentially, the method consists in the simulation of a (limited) number of computer particles, each of which represents a large number of physical particles (ions and electrons). The movement of the particles is simply calculated from Newton s laws of motion. Within the PIC method the movement of the particles and the evolution of the electric field are followed in finite time steps. In each calculation cycle, first the forces on each particle due to the electric field are determined. Then the [Pg.66]

There are special numerical analysis techniques for solving such differential equations. New issues related to the stabiUty and convergence of a set of differential equations must be addressed. The differential equation models of unsteady-state process dynamics and a number of computer programs model such unsteady-state operations. They are of paramount importance in the design and analysis of process control systems (see Process control). [Pg.80]

The determination of the critical GLC is a trial and error computation of GLC s due to various wind speeds, atmospheric stabilities and downwind distances. The maximum value obtained from these procedures is the critical GLC. Because of the number of computations involved, calculations should be performed on the computer. Software simulation is also necessary to calculate GLC s due to multiple stack cases. Wind direction is an additional variable that must be taken into account with multiple stact cases. [Pg.358]

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