Application of Computer Programs

The reader is urged to read Initiation of Explosives by Impact in Vol 7,135-R ff of this Encycl, Whereas that article dealt principally with the testing of expls, we shall want to include propints in the discussion. There is probably no subject in hazards analysis which is so actively studied as the role of impact, shock and thermal effects on the safety of expls and proplnts and which is as poorly understood. We have alluded to this incomplete state of theoretical development in the section of this article on Application of Computer Programming... 

The above example shows two things. First, variation theory can provide a more accurate value for the energy of a system. Second, it comes at a cost a cost of effort. However, using computers to do the calculations, the personal effort can be minimized, so variation theory is particularly well suited for computer applications. In fact, a majority of the effort expended in the modern application of quantum mechanics is in the application of computer programs. Because computers can be programmed with a large number of variables to change in the course of a calculation, variation problems are almost exclusively performed on computers. 

W. E. Johnson, Development and Application of Computer Programs Related to Hypervelocity Impact , Systems, Science and Software report 3SR-353 (1970). 

The calculation of vapor and liquid fugacities in multi-component systems has been implemented by a set of computer programs in the form of FORTRAN IV subroutines. These are applicable to systems of up to twenty components, and operate on a thermodynamic data base including parameters for 92 compounds. The set includes subroutines for evaluation of vapor-phase fugacity... 

As computers become more pervasive and increasingly powerful, specialized programs and databases are being developed to assist in a wide variety of research efforts. This is true in the search for solvent alternatives, and in this section we review the application of computers to solvent substitution studies and cover computer-aided molecular design of new solvents, methods developed for the prediction of physical properties, methods for predicting less precise chemical characteristics such as toxicity and carcinogenicity, and computer-aided design of alternative synthetic pathways. 

SC (simultaneous correction) method. The MESH equations are reduced to a set of N(2C +1) nonlinear equations in the mass flow rates of liquid components ltJ and vapor components and the temperatures 2J. The enthalpies and equilibrium constants Kg are determined by the primary variables lijt vtj, and Tf. The nonlinear equations are solved by the Newton-Raphson method. A convergence criterion is made up of deviations from material, equilibrium, and enthalpy balances simultaneously, and corrections for the next iterations are made automatically. The method is applicable to distillation, absorption and stripping in single and multiple columns. The calculation flowsketch is in Figure 13.19. A brief description of the method also will be given. The availability of computer programs in the open literature was cited earlier in this section. 

Banzhaf W, Nordin P, Keller RE and Francone FD 1998 Genetic Programming - An Introduction On The Automatic Evolution of Computer Programs and Its Applications. Morgan Kaufmann Publishers, San Francisco, California. 

By application of computer and associated programs for optimization with limitations-compromising optimization, the composition of the composite has been determined ... 

Greater access to relatively powerful computing capability has seen theoretical studies move even further into mainstream chemistry over the past 10 years. In particular, the availability of a multitude of computer programs that support density functional theory (DFT) has seen a variety of applications of relatively complex molecules and reactive intermediates that would not have been possible at the time of the last review. Individual applications of DFT will not be covered here however, specific examples will be included in subsequent sections where pertinent. 

From the chemists viewpoint the technique has been pioneered by Kowalski, who has described it very clearly in benchmark papers30 31) reviewed it32), demonstrated that it is equally applicable to the classification of the clays used in ancient pottery and to the identification of oils from spillage incidents 33), and has made his set of computer programs ARTHUR available to the scientific community. Many others, have been active within the area and their work has been comprehensively reviewed by Kryger341 and Varmuza35) who has also described virtually all of the techniques which have been applied. All of these have important features in common ... 

The most popular application of computers involves programs developed for modeling corrosion and cracking as well as programs for diagnosis, failure analysis and prediction/ analysis. The systems developed are ... 

The types of computer programs which have been applied in corrosion engineering and science fall into categories such as (i) conventional software systems (ii) artificial intelligence and expert systems applications (iii) object-oriented software systems ... 

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