Abstract:
In a numerical simulation system, a method for displaying information includes the steps of generating output data of values which are dependent on at least one of coefficients and constants of a discretization equation at each mesh point, based on positions of the mesh points representing the analysis domain and having the partial differential equation defined therefor and simultaneous linear equations constructed by the discretization equations which are approximation equations of the partial differential equations; displaying the analysis domain on a display; and changing the display status of the display screen at the point corresponding to the mesh point depending on the output data at the mesh point.
Abstract:
A program generation method for generating a program which performs numerical simulation on a computer for a physical phenomenon by entering, to the computer, shape information of a spatial region in which the physical phenomenon takes place, conditions of numerical simulation including variables and constants necessary for the numerical analysis of the physical phenomenon, a partial differential equation using the variables and constants, and initial condition, boundary condition and material coefficient of the spacial region, and equation information including computational procedures. The formula information of an entered simulation model is analyzed to detect lacking information and the shape information of the simulation model is analyzed to detect parts, in correspondence to the shape information, in the spatial region in need of setting further equation information in addition to the first-mentioned equation information, and the detected lacking equation information and information of detected parts are analyzed in need of setting further equation information and the lacking equation information and the detected parts for which the lacking information is to be set are displayed, thereby prompting a user in an interactive manner to enter the lacking equation information, and a numerical simulation program is generated using the information of simulation model entered initially and supplementary equation information entered by the user.
Abstract:
A recording device which is capable of preventing alteration of a generated digital picture data and suitable for improving the reliability of the digital picture data as an evidence. The recording device includes a related information embedding unit for embedding a related information on the digital picture data stored in a related information storing unit in the digital picture data obtained by a picture receiving unit by means of the digital watermarking technique, a digital signature generating unit for generating a digital signature of the digital picture data in which the related information has been embedded, and a recording unit for adding the digital signature to the digital picture data in which the related information has been embedded and storing it in a memory unit.
Abstract:
A program generating method for automatically generating a program used in a simulation of a physical phenomenon by using computers, wherein inputted information such as the shape of a domain where the physical phenomenon such as that in a fluid takes place, mesh division information therefor, a partial differential equation dominantly representing the physical phenomenon and boundary conditions thereof are inputted, differential operators included in the inputted partial differential equation and an equation representing the boundary condition are expanded to generate discrete equations and the generated discrete equations are coded to automatically generate simulation programs. Information indicating whether discrete points which are evaluation points of the values of variables included in the inputted partial differential equation are located at mesh points or at intermediate points between mesh points is inputted the relative positional relations between mesh points and the discrete points of the variables, and relative discrete equations are generated in accordance with the inputted information by discretizing the differential operators included in the partial differential equation by using a conversion table or a conversion program, where the position of a variable to be solved in the partial differential equation is designated as a reference point relative discrete equations are converted to discrete equations for an absolute position in the region where the physical phenomenon takes place, thereby generating the simulation program.
Abstract:
A method is provided for automatically generating a simulation program which numerically solves a partial differential equation which governs a physical quantity in a non-rectangular real space domain. The real partial differential equation is solved according to a boundary-fitted method by first transforming the original partial differential equation from a real space to a normal space. The upper limit of user work area memory available on the data processing apparatus and the number of mesh points extracted from the real space domain shape are considered in the transformation and to an extent control the transformation rule. Two program statements are thus generated, the first of which allocates data area for the particular variables in the work area memory. The second program statement defines the value of each variable in terms of one factor. The final step combines the partial differential equation and the first and second program statements into a simulation program which is used to solve the original partial differential equation.
Abstract:
The partial differential equations inputted with respect to an unknown quantity A are processed according to the finite element method in which simultaneous first-order equations equivalent to the partial differential equations are obtained, and then a matrix equation equivalent to the simultaneous first-order equations, namely, (k.sub.ij) (a.sub.i)=(d.sub.i) is processed to derive a coefficient {a.sub.j } so as to generate a program which calculates the unknown quantity A. For each group of a plurality of elements, the program calculates a contribution determined by the positions of the nodes associated with the elements with respect to a portion of matrix element group such as k.sub.lm and k.sub.ll and a portion of constant group such as d.sub.l and d.sub.m determined by the numbers assigned to a plurality of nodes contained in the group of a plurality of elements and then generates the final values of the matrix element group {k.sub.ij } and the constant {d.sub.i } from the contribution calculated for each group of a plurality of elements.
Abstract:
The entry of a problem describing program is assisted by a database or a display screen. An error in numerical calculation of the input problem describing program is automatically checked. A simulation program which interrupts the execution of a process requsted by a statement in the problem describing program which a user designates as a break point when the simulation program executes the process is automatically generated. At the time of interruption, the execution status of the simulation is diagnosed upon the user's request.
Abstract:
Method for generating a program for numerically solving a partial differential equation, wherein when a numerical calculation program for calculating, in a specified analytic domain, the value of a physical quantity defined by a partial differential equation is automatically produced, it is judged on the basis of predetermined conditions whether or not discretization due to the divergence of an operand is to be carried out for each of terms which are included in the partial differential equation and have a differential operator, and the discretization due to the divergence of the operand is carried out for a term when it is judged that the term is to be discretized on the basis of the divergence of the operand.
Abstract:
A method for automatically generating by use of a computer a simulation program for simulating a phenomenon in a region by discretizing automatically data of a partial differential equation inputted when the partial differential equation and boundary conditions governing the phenomenon and data representing the shape of a region, which is an object of calculation, are given, by using a discretization rule by the finite differential method, and for generating a program calculating numerical values representative of the phenomenon determined by the partial differential equation over the whole object region of calculation by the finite differential method on the basis of the equation after the discretization, wherein the object region of calculation is divided into a plurality of blocks, each of which has the same differential equation and the same discretization rule and a program is generated which calculates, for each of the blocks numerical values representative of the phenomenon determined by the partial differential equation and the discretization rule both applied for each of the blocks by the finite differential method.
Abstract:
In a computer system including a plurality of computers interconnected through a network, a specific computer A in the computer system manages the computer resource information and the operating condition information such as for a CPU, a file and a memory and the user resource information such as file data and a program of each computer of the computer system. When a user issues a request from a computer C to log in to the computer system, the request is reported to the computer A, and the information related to the user is returned to the computer C with reference to the user resource information held by the computer A. Then, the computer C acquires the file and the usable program held by the user in the computer system and executes a process, whereby the whole system can be used as resources of each user.