1. NAME AND TITLE

EXPRESS: Exact Preparedness Supporting System.

2. CONTRIBUTOR

Japan Atomic Energy Research Institute, Ibaraki-ken, Japan, through the NEA Data Bank, Issy-les-Moulineaux, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; VAX and IBM 3090.

4. NATURE OF PROBLEM SOLVED

The emergency response supporting system EXPRESS (EXact PREparedness Supporting System) was developed to calculate real-time predictions of affected areas due to radioactivities discharged into the atmosphere from nuclear facilities.

5. METHOD OF SOLUTION

The computational models in EXPRESS are the mass-consistent wind field model (EXPRESS-I) and the particle dispersion model (EXPRESS-II) for atmospheric dispersions. The real-time ability of the code is obtained using a high-speed iteration method, MILUCR (Modified Incomplete Linear Unitary Conjugate Residual), in EXPRESS-I and a kernel density method in EXPRESS-II. EXPRESS-II employs a random walk model based on gradient-transfer theory.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

Execution times for the sample problems on a VAX 6000-420 were:

EX1 3 minutes 46 seconds

EX1S 3 minutes 37 seconds

EX2 1 minute 31 seconds

8. COMPUTER HARDWARE REQUIREMENTS

A minimum of 8 megabytes of disk storage is recommended by the author. The code was developed to run on Unix workstations. It has also run on FACOM, IBM 3090, and VAX systems.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran 77 compiler is required. RSIC tested the codes on a VAX 6000-420 running VMS 5-5.2 and VAX Fortran-77 v.5-9.

10. REFERENCE

Masamichi, CHINO, "Manual of a Suite of Computer Codes, EXPRESS (Exact Preparedness Supporting System)," JAERI-M 92-082 (June 1992).

11. CONTENTS OF CODE PACKAGE

The referenced document and one DS/HD 5.25-in. (1.2 MB) diskette are included. The code package contains sample input and output and the EXPRESSI, EXPRESSIS, and EXPRESSII source files written in self-extracting compressed DOS files.

12. DATE OF ABSTRACT

February 1994.