Hitachi Engineering Co., Ltd.

Masami Shiozawa

Haruki Inoue

Mayumi Mizutani

Kenichi Nakamura

Hideo Yoshida

Hitoshi Onizawa

Satoru Yoshikawa

Yukio Hamaguchi

A planning system includes an input device which accepts at least a given planning problem and values of variables required to solve the given planning problem; a display device which provides a visual display of an optimum plan obtained for the given planning problem; and a planner device which prepares an objective function representing items to be averaged and designs a plan to minimize a value of the objective function. The planner device includes an initial plan reader which reads an initial plan; an objective function value operation unit which calculates an objective function value of the initial plan; a reproduction unit which generates random numbers to a set composed by elements contacting to boundary planes of divided subsets, wherein the random numbers include a range of number of contacting elements and an equally-opportunity-selectable distribution, select at least one element based on the random numbers, equal-opportunity-selecting one of the subsets to which element contacts, and schedule the plan such that the selected element is rendered to belong to the selected subset; a plan renewal unit which compares the objective function value of the current plan with the objective function value of the previous plan to determine the plan having a smaller objective function value as an optimum plan; and a control unit which provides a visual display of an optimum plan on the display device.

Planning system and planning method

A system for making an optimum plan for a given problem at high speed. The system sets a planning problem, etc., prepares an objective function and finalizes a plan for minimizing or maximizing the objective function value, and then stores necessary variables. The system prepares as many parent plans of a first generation as a given number (population), calculates objective function values, sorts plans in descending or ascending order of the objective function values of the plans, when selection numbers are assigned to plans in order of a ratio of the objective function value of each plan to the total of the objective function values of the plans, selects parent plans by using numbers indicated by as many constants as the population determined for each generation as the selection numbers, and replaces two elements, arranged at order positions specified by random numbers, with each other for each of the selected parent plans, to prepare child plans.

Planning method and system

Growing community of inventors

Hitachi, Japan

Masami Shiozawa