Issue N^{o} 1, 1983 
A MULTICOMPUTER SYSTEM AND ITS PERFORMANCE MODEL FOR CONTINUUM MECHANICS PROBLEMS
I. D. Sofronov, S. P. Belyaev Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 313.
The paper studies parallel algorithm development feasibility for solving continuum mechanics problems and the efficiency of its multicomputer inplementation. A problem to be solved is assumed to have as many processors as desired which form a homogeneous computer system running under a general  purpose computer control. For the main classes of difference schemes and a number of irregular grid methods, parallel algorithms, maximum  usage processor number, and potential computation speedup estimates are given.

ROTATION INVARIANT SECOND ORDER EQUATIONS I. A. Adamskaya, S. P. Belyaev Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 1419.
Second order equations, invariant with respect to space rotation are considered. A matrix structure with second derivatives is investigated. An explicit matrix form is found.

PUTTING TOGETHER EXPLICIT AND IMPLICIT SCHEMES FOR SOLVING NUMERICAL GAS DYNAMICS PROBLEMS O. M. Kozyrev Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 2025.
The paper proposes an algorithm to put together explicit and implicit schemes used for numerical integration of gas dynamics equations across a Lagrangian boundary. An example of acoustic equations shows the scheme stability resulted from putting together two different schemes along with a difference solution convergence to an accurate one. Numerical results are presented.

AN APPROXIMATE METHOD FOR THE CALCULATION OF HEATING LASER TARGETS BY NON EQUILIBRIUM CORONA RADIATION V. A. Lykov, V. G. Nikolaev Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 2631.
An analitic solution for a compressed target portion heated by a non  equilibrium corona radiation is obtained. This solution is incorporated into a threetemperature program which allowed also to take into account streaming quantums in a threetemperature approximation. For conventional three  temperature problem computation time, solutions sufficienily close to full spectrum calculations were found. Thus, the approximate method proposed proved to be reasonable for laser target calculations.

AN APPROXIMATE CALCULATION OF ANGULAR DISTRIBUTION COEFFICIENTS FOR THERMAL RADIATION FROM A ROTATION SURFACE Yu. A. Dementiev, R. F. Mashinin, V. F. Mironova, N. N. Chentsov Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 3234.
The Babayev equation is used to describe a timedependent thermal radiation transport through a region with a negligibly weak material/radiation interaction in terms of delaying and shadowing effects. The cavity surface is assumed to be composed of several rotation surfaces with respect to a common axis. A calculational grid is mapped onto the cavity surface and the equation is approximated by a system of algebraic equations. The equation coefficients are geometrically considered as angular coefficients and average distances; so their estimations requires fourgold integerals to be calculated over a complex integration region. A procedure for approximate calculation of coefficients relying, when possible, on analytic computations is described.

MAXIMUM/MINIMUM PRINCIPLE FOR SOLVING A FIXED MEDIUM RADIATION PROPAGATION PROBLEM Ye. S. Andreev, M. Yu. Kozmanov Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 3536.
The radiation propagation in a fixed medium is considered. Maximum/minimum principle is proved for sys35 terns of differential and difference equations describing a timedependent spectral radiation and energy transport. A characteristic method is used to obtain a difference approximation of a system of differential equations. The maximum/minimum principle validity for the difference problem solution shows that uncertainty cannot grow infinitely.

GEOMETRY CHARACTERIZATION OF MAT SPHERICAL REFLECTORS O. B. Feodoritova, N. N. Chentsov Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 3740.
The following feature is known from the geometrical scattering optics. Suppose, S is a perfectly black spherical surface. If some portion is radiating inward according to the Lambert law, then the rest of the surface has an identical illumunation intensity at any point. This spherical surface feature is proved to be characteristic. In this connection the features of spherical shields, as radiation homogenizators within the simplest ball model surrounded by a shield, are discussed. A possibility to use the opticsgeometry dependences analyzed is pointed out.

COMPUTATION OF A P0L0IDAL MAGNETIC FIELD IN TOKAMAK S. G. Bespoludennov, P. N. Vabishchevich, L. M. Degtyarev, V. V. Drozdov, V. I. Pistunovich Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 4151.
The calculation of an external magnetic field generated by circular currents to form an equilibrium plasma configuration having preset features is considered. The currents are found from the condition of plasma boundary proximity to a given one and that of mgnetic fluxes frozen in the plasma. A technique for solving a selfconsistent problem in external fields relies on variable conversion. The calculational results for the INTOR poloidal megnetic field are given.

A THIN CYLINDER SHELL MOTION SIMULATION USING A BOUNDARY CONDITION FOR THE VULCAN TECHNIQUE V. V. Bashurov Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 5256.
The calculation of ground motion generated by a punch covered with a thin cylinder shell is studied. Direct solution of such a problem using the VULCAN finitedifference scheme is shown to be costineffective. It is proposed to replace the shell by a normal stress boundary condition resulting from an analysis of a thin elasticplastic shell behavior under loading.

A METHOD FOR SOLVING RADIATION GAS DYNAMICS EQUATIONS A. I. Zuyev, N. G. Karlykhanov Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 5760.
A method for solving equations governing the energy transfer by thermal radiation in combination with electron and ion heat conduction is presented. The thermal radiation is represented by a spectral diffusion approximation. The performance of the method proposed and that of its modifications are illustrated by some test computations. The method can be used to solve radiation gas dynamics equations with a complicated heat transfer.

SOME CALCULATIONAL RESULTS FOR THERMODYNAMIC FUNCTIONS DETERMINED BY A SELFCONSISTENT FIELD METHOD WITH LOCAL EXCHANGE N. M. Barysheva, G. V. Sinko Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 6162.
Some results of the aluminium and iron Hugoniot adiabat calculations using a selfconsistent field method with local exchange are given. Several features of adiabat behavior arising when taking into account the shell effects are discussed. Iron is recommended as a reference material for tests associated with relative compressibility at superhigh pressures.

SENSE MATCHING CRITERIA FOR A FACTOGRAPHIC COMPUTERAIDED INFORMATION SYSTEM A. P. Kuclaev Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1983. No 1. P. 6368.
The paper considers the main criteria of an information retrieval and output in response to a facto graphic information reference system user request. The concepts for using logic sense matching criteria in a factographic system are developed. Some examples are given which illustrate request variations within systemuser interaction process in iterative mode.

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