Yuji Taniguchi

Transmission control for time-critical messages in packet-switching communication nets

A study is made of the control algorithms for the transmission of time-critical messages. Each message comprises packets with unit data length. The objective is to minimize the maximum tardiness of the messages. Optimal algorithms are presented for communication nets with in-tree or out-tree structures. A heuristic algorithm is presented for more general hierarchical communication nets.<<ETX>>

Scheduling jobs on a multiprocessor system with a common memory

This paper studies the problem of scheduling jobs on a multiprocessor system with a common memory to minimize , where fi denotes flow-times of jobs i, and wi(fi) denotes monotonically nondecreasing functions of fi. Arriving jobs are assigned to available processors according to an appropriate scheduling rule. Once a job is placed on a processor, it retains the processor during its processing and repeats local computations and accesses to the common memory. First, the scheduling problem is formulated into a zero-one integer programming problem. Next, a procedure is presented for computing a lower bound on the optimal cost. Finally, the performance of the proposed procedure is evaluated using simulation experiments for the problem of minimizing mean flow-time.