In sanitary inquiries my attention was early directed to instances of layers or strata of air of malarious influence, sucli as this : A medical officer, pointing to a mist, spread like a sheet over a valley, said, " That sheet just covers the bulk of my patients; out of it or above it I have nothing scarcely but midwifery cases and accidents. I have, had instances of children whose heads were a...

this paper addresses the problem of minimizing the sum of maximum earliness and tardiness on identical parallel machines scheduling problem. each job has a processing time and a due date. since this problem is trying to minimize and diminish the values of earliness and tardiness, the results can be useful for just–in-time production systems. it is shown that the problem is np-hard. using effici...

Appropriate scheduling and sequencing of tasks on machines is one of the basic and significant problems that a shop or a factory manager encounters; this is why in recent decades extensive studies have been done on scheduling issues. One type of scheduling problems is just-in-time (JIT) scheduling and in this area, motivated by JIT manufacturing, this study investigates a mathematical model for...