Computer, general-purpose

The Ferranti-Shidey viscometer was the first commercial general-purpose cone—plate viscometer many of the instmments stiU remain in use in the 1990s. Viscosities of 20 to 3 x 10 mPa-s can be measured over a shear rate range of 1.8-18, 000 and at up to 200°C with special ceramic cones. Its features include accurate temperature measurement and good temperature control (thermocouples are embedded in the water-jacketed plate), electrical sensing of cone—plate contact, and a means of adjusting and locking the position of the cone and the plate in such a way that these two just touch. Many of the instmments have been interfaced with computers or microprocessors. 

GPSS/PC, developed by Minuteman Software (Stow, Mass.) for IBM-compatible personal computers, is based on the popular discrete simulation language GPSS (general purpose simulation system). Reference 14 provides more details. 

The observation that certain kinds of parallel-computing architectures best support only certain kinds of problems seems to be general. The further observation that interprocessor communication can be the primary impediment to parallel performance is also general. As of this writing, any hope of a truly general purpose parallel computer seems to be remote. The best hope may He in software efforts that describe problems at higher levels of abstraction, which can then be ported and optimized for different parallel architectures (22). 

Listed is a collection of general-purpose molecular dynamics computer simulation packages for the study of molecular systems. The packages include a wide variety of functionalities for the analysis and simulation of biomolecules. In addition, they contain integrated force fields. 

GROMOS A general-purpose molecular dynamics computer simulation package for the study of biomolecules http //igc.ethz.ch/gromos/weicome.htmi GROMACS (GROningen MAchine for Chemical Simulations) http //rugmdO. chem. rug.ni/ gmx/... 

Spalding, D. B. 1981. A general purpose computer program for multi-dimensional one- and two-phase flow. Mathematics and Computers in Simulation, IMACS, XXll. 267-276. 

Some programs require only a few days to completely program for general purpose use, while some others require several montlis of continuous effort. Whenever more than one individual is expected to use the computer program, it is good practice to obtain the several tiews on attacking the problem, i.e., qqje of input data, solution approach, range of variables, fixed conditions and type and form of output or results. 

What is remarkable about this very simple appearing rule is that one can show that it is capable of univer.sal computation. This means that with a proper selection of initial conditions (i.e. the initial distribution of live and dead cells). Life can be turned into a general purpose computer. This fact fundamentally limits the overall predictability of Life s behavior. 

Class c4 Rules, T20 (r=2) and T88 (r=3) It has been conjectured that all generic class c4 CA are capable of universal computation [wolf85e]. With initial configurations specifying arbitrary algorithmic procedures, such systems can effectively evaluate any computable function and therefore mimic the action of any general purpose computer. 

Although the formal meaning of this statement will be discussed greater detail a bit later in this section, its profound implication is just as easy to appreciate informally. By virtue of being a universal computer, a proper selection of initial conditions can ensure that Life can be made to carry out arbitrary algorithmic procedures - i.e.. Life can serve as a general purpose computer . 

In this short initial communication we wish to describe a general purpose continuous-flow stirred-tank reactor (CSTR) system which incorporates a digital computer for supervisory control purposes and which has been constructed for use with radical and other polymerization processes. The performance of the system has been tested by attempting to control the MWD of the product from free-radically initiated solution polymerizations of methyl methacrylate (MMA) using oscillatory feed-forward control strategies for the reagent feeds. This reaction has been selected for study because of the ease of experimentation which it affords and because the theoretical aspects of the control of MWD in radical polymerizations has attracted much attention in the scientific literature. 

Dyall. K.G., Grant, I.P., Johnson, C.T., Parpia, F.A. and Plummer, E.P. (1989) GRASP A general-purpose relativistic atomic structure program. Computer Physics Communications, 55, 425 56. 

The 21 equations (given as Equation 6.68) should be solved simultaneously with the three state equations (Equation 6.64). Integration of these 24 equations yields x(t) and G(t) which are used in setting up matrix A and vector b at each iteration of the Gauss-Newton method. Given the complexity of the ODEs when the dimensionality of the problem increases, it is quite helpful to have a general purpose computer program that sets up the sensitivity equations automatically. 

Dueck, G. and T. Scheuer, "Threshold Accepting A General Purpose Optimization Algorithm Appearing Superior to Simulated Annealing", J. Computational Physics, 90,61 (1990). 

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