Computer flow charts

The reaction flow-charts of Part Two, and indeed all chemical formulae which appear in this book, were generated by computer. The program used for these drawings was ChemDraw adapted for the Macintosh personal computer by Mr. Stewart Rubenstein of these Laboratories from the molecular graphics computer program developed by our group at Harvard in the 1960 s (E. J. Corey and W. T. Wipke, Science, 1969,166, 178-192) and subsequently refined. 

Figure 49. Flow chart to compute the pit pattern-formation process." (Reprinted from M. Asanuma and R. Aogald, Morphological pattern formation in pitting corrosion, J. Electroanal. Chem. 396, 241,1995, Fig. 6 Copyright 1995, reproduced with permission from Elsevier Science.)...

Pitting potential, determination of, 258 Pit-patent formation, flow chart to compute, 298 Platinum Clavilier, 135... 

Laboratory applications of the computer, as evidenced by this symposium, are concentrating more on the result, and less on the hardware required to accomplish that result. A few years ago, a symposium of this type would have concentrated on the automated collection and analysis of data from laboratory instrumentation. Each paper would read like a chapter from "Tom Swift and His Electric Lab Whiz" and would dwell on the details of circuit diagrams and program flow charts. These papers were presented by... 

Strong, H. R., "Translating Recursion Equations into Flow Charts," J. Computer System Sciences, 5 (1971) 254-285. 

The I2 system has been investigated experimentally, theoretically, and computationally by several groups, as a prototype for the study of dissociation and recombination dynamics influenced by the interactions with a surrounding solvent or cluster of solvent molecules[9],[36]-[41]. The system can be effectively modelled by two VB states[9],[41], which allows a focus on several key aspects of the implementation of the theory, without being hindered by the complexity of a multistate calculation. The implementation steps are conveniently collected in the flow chart in Table 1, to which the reader is referred to for a comprehensive overview of our strategy. All the details of the calculation are reported in BH-II. The effective wave function for the I2 reaction system can be written as... 

Decomposition leads to a rearrangement of the process equations from their flow chart sequence to a natural sequence based on the information flow among the equations. The ultimate goal is to set up an iterative scheme in which each equation is solved for a single variable (by some appropriate root identification method), and where values of unknown variables that must be assumed are checked cyclically. The greatest reduction in the number of iterates that must be assumed, and therefore the greatest reduction in computer storage and time requirements, takes place for those systems of process equations in which the number of variables per equation is small compared to the total number of variables in the system. Clearly, when each of the system equations contains every process variable, no effective decomposition can take place. Fortunately, most models used in the process industries are of such a character that extensive decomposition can be effected. 

We first follow the flow chart for the simple case of elastic scattering of structureless atoms. The number of internal states, Nc, is one, quantum scattering calculations are feasible and recommended, for even the smallest modem computer. The Numerov method has often been used for such calculations (41), but the recent method based on analytic approximations by Airy functions (2) obtains the same results with many fewer evaluations of the potential function. The WKB approximation also requires a relatively small number of function evaluations, but its accuracy is limited, whereas the piecewise analytic method (2) can obtain results to any preset, desired accuracy. 

Problem 12 Explain the terms (i) computer programming and (ii) flow charts. 

In Fig. 1 we show the system control flow chart. The laser and computer system, after recharging from the previous laser shot, was armed and readied for a seed particle to flow through the LV probe region. Either 1 ym diameter alumina or 0.25 ym titanium dioxide was used to seed the flame. The particle count rate was continuously adjustable from 0.2 to 1000 valid velocity measurements per second. For initial development purposes, an average 0.5 s particle interarrival delay was chosen. 

The program (TGPL78) and its associated subroutine (AX12) written in FORTRAN, are reproduced as Appendixes II and III. A computer-drawn flow chart of the program is shown in Appendix IV. In the computer memory we have a large file of our Chinese bronze analyses both for major and trace elements. Some additional data as to the bronze type, date, provenance, whether it has been dated by thermoluminescence, and what the lead isotope ratios are if measured are also in this file. For the 150 Chinese belt hooks which we have analyzed, we also include three lines of shape and typological data. 

Figure 6. Flow chart for the computer program logic in IMD-4 analytical converter model.

In this flow chart is the end-point of integration, is the start-point of integration and NSTEP is the number of steps. The computation of qh zu i = 1(1)3 is based on the Runge-Kutta-Nystrom method of Dormand and Prince 8(7) (see 9-10). 

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