FORTRAN system

The realization of these strategies into a FORTRAN system package resulted in converging solutions for a large number of reasonably sized data sets (net adjustments with 300 to 400 unknown points) where even large blunders were present. 

Attempts were made to explore the impact of several parameters on the design of the ETBE system. Convergence issues and frequent Fortran system errors severely limited this investigation. 

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... 

The calculation of single-stage equilibrium separations in multicomponent systems is implemented by a series of FORTRAN IV subroutines described in Chapter 7. These treat bubble and dewpoint calculations, isothermal and adiabatic equilibrium flash vaporizations, and liquid-liquid equilibrium "flash" separations. The treatment of multistage separation operations, which involves many additional considerations, is not considered in this monograph. 

Evaluation of the activity coefficients, (or y for noncondensable components),is implemented by the FORTRAN subroutine GAMMA, which finds simultaneously the coefficients for all components. This subroutine references subroutine TAUS to obtain the binary parameters, at system temperature. 

The computation of pure-component and mixture enthalpies is implemented by FORTRAN IV subroutine ENTH, which evaluates the liquid- or vapor-phase molar enthalpy for a system of up to 20 components at specified temperature, pressure, and composition. The enthalpies calculated are in J/mol referred to the ideal gas at 300°K. Liquid enthalpies can be determined either with... 

The computer subroutines for calculation of vapor-phase and liquid-phase fugacity (activity) coefficients, reference fugac-ities, and molar enthalpies, as well as vapor-liquid and liquid-liquid equilibrium ratios, are described and listed in this Appendix. These are source routines written in American National Standard FORTRAN (FORTRAN IV), ANSI X3.9-1978, and, as such, should be compatible with most computer systems with FORTRAN IV compilers. Approximate storage requirements and CDC 6400 execution times for these subroutines are given in Appendix J. 

The subroutines PARIN and PARCH are source routines written in American National Standard FORTRAN (FORTRAN IV), ANSI X3.9-1978, and should be compatible with most computer systems where input can be taken from logical unit 3. 

The programs DRFLA for vapor-liquid and DRELI for liquid-liquid calculations are written in FORTRAN IV source language for the CDC 6400 of the Computer Center, University of California, Berkeley. Minor modifications, mostly with regard to input and output, will be required for implementation on most other computer systems. 

The program storage requirements will depend somewhat on the computer and FORTRAN compiler involved. The execution times can be corrected approximately to those for other computer systems by use of factors based upon bench-mark programs representative of floating point manipulations. For example, execution times on a CDC 6600 would be less by a factor of roughly 4 than those given in the tcible and on a CDC 7600 less by a factor of roughly 24. 

A very pedagogical, highly readable introduction to quasi-Newton optimization methods. It includes a modular system of algoritlnns in pseudo-code which should be easy to translate to popular progrannning languages like C or Fortran. 

SHMO is a simple Huckel MO program in FORTRAN that functions much as MOBAS does and is also based on the Dickson program. The SHMO source code must be compiled. Compiled SHMO is in executable code (.exe). Run SHMO from the system level (do not go into BASIC) with the single command... 

Seeing the success of the UNAMAP BBS, EPA s Office of Air Quality Planning and Standards started a BBS for information on regulatory models in June 1989. This has expanded to a BBS called TTN, Technology Transfer Network. This BBS, in Durham, NC, is reached on (919) 541-5742 and the system operator on (919) 541-5384. A part of this BBS called SCRAM, Support Center for Regulatory Air Models, contains model FORTRAN codes, model executable codes for use on personal computers, meteorological data, and in some cases model user s guides. Much of the information is downloaded in "packed" form, and software to unpack the files must also be downloaded from the bulletin board. 

The program can solve both steady-state problems as well as time-dependent problems, and has provisions for both linear and nonlinear problems. The boundary conditions and material properties can vary with time, temperature, and position. The property variation with position can be a straight line function or or a series of connected straight line functions. User-written Fortran subroutines can be used to implement more exotic changes of boundary conditions, material properties, or to model control systems. The program has been implemented on MS DOS microcomputers, VAX computers, and CRAY supercomputers. The present work used the MS DOS microcomputer implementation. 

Programming languages for the LCAP systems comprises traditional FORTRAN and FORTRAN-like directives which are interpreted by a precompiler developed in our laboratory. The directives provide syntactical constructs for interprocessor communication and synchronization. A detailed description of the implementation of our quantum chemistry package HONDO has been given elsewhere. (Dupuis, M. Watts, J. D. Theor. Chim. Acta, in press.) Our experience indicates that the calculations done in the study described above were executed in parallel at a very high level of efficiency. 

Except for certain library routines used to drive the interface hardware and some system specific routines from the system library, all of the routines are written in a dialect of FORTRAN IV and they are sufficiently modular and portable to be adaptable to other combinations of computers and chromatographs. 

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