Analog arithmetic circuit with electric resistor networks and numerical solution method of fourth-order partial differential equation by the use of the circuit

摘要

In order to carry out dynamic analysis of a phenomenon described by a fourth-order partial differential equation of a function, an analog arithmetic circuit includes a Poisson's circuit (11) and a Laplace's circuit (15). The Poisson's circuit (11) includes a resistor network, additional resistors (R) having one ends connected to nodes of the resistor network, respectively, and subtractor circuits (13) each of which is for subtracting a predetermined voltage from a node voltage at each node to produce an output voltage supplied to the other end of the additional resistor connected to each node. External and boundary voltages are applied to the resistor network. The Laplace's circuit (15) comprises a similar resistor network. Each of the nodes of the Laplace's circuit is connected to the corresponding one of the subtractor circuits to supply the predetermined voltage. Each of calculating circuits (17) connected to peripheral terminals of the Laplace's circuit calculates a voltage from the external and boundary voltages and the node voltage to produce a calculated voltage supplied to the peripheral terminals. Thus, the node voltages provide solutions of the function.