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Optimal Policies for a Database System with Two Backup Schemes

Cunhua Qian, Yu Pan, Toshio Nakagawa (2010)

RAIRO - Operations Research

This paper considers two backup schemes for a database system: a database is updated at a nonhomogeneous Poisson process and an amount of updated files accumulates additively. To ensure the safety of data, full backups are performed at time NT or when the total updated files have exceeded a threshold level K, and between them, cumulative backups as one of incremental backups are made at periodic times iT(i = 1,2,...,N - 1). Using the theory of cumulative processes, the expected cost is obtained,...

Parallel machine scheduling with uncertain communication delays

Aziz Moukrim, Eric Sanlaville, Frédéric Guinand (2003)

RAIRO - Operations Research - Recherche Opérationnelle

This paper is concerned with scheduling when the data are not fully known before the execution. In that case computing a complete schedule off-line with estimated data may lead to poor performances. Some flexibility must be added to the scheduling process. We propose to start from a partial schedule and to postpone the complete scheduling until execution, thus introducing what we call a stabilization scheme. This is applied to the m machine problem with communication delays: in our model an estimation...

Parallel Machine Scheduling with Uncertain Communication Delays

Aziz Moukrim, Eric Sanlaville, Frédéric Guinand (2010)

RAIRO - Operations Research

This paper is concerned with scheduling when the data are not fully known before the execution. In that case computing a complete schedule off-line with estimated data may lead to poor performances. Some flexibility must be added to the scheduling process. We propose to start from a partial schedule and to postpone the complete scheduling until execution, thus introducing what we call a stabilization scheme. This is applied to the m machine problem with communication delays: in our model an estimation...

Currently displaying 121 – 140 of 183