Batch culture of Ralstonia eutropha using the recycled gas closed circuit culture system was conducted in order to develop a practical fermentation system for industrial autotrophic culture for poly (hydroxybutrate) production. The gas phase of the culture system consisted of substrate gas so that gases in this culture could be recycled as long as the amount of the gas consumed would be repleni...

We analyze an infinite-server queueing model with synchronized arrivals and departures driven by the point process {Tn} according to the following rules. At time Tn, a single customer (or a batch of size βn) arrives to the system. The service requirement of the ith customer in the nth batch is σi,n. All customers enter service immediately upon arrival but each customer leaves the system at the ...

With Bursty Task Arrivals Chin LU and Sau-Ming LAU Computer Science Department The Chinese University of Hong Kong Shatin, Hong Kong Email: fclu, [email protected] AbstractUsually heuristic-based load balancing algorithms cannot provide satisfactory performance with bursty task arrivals because they assume stable arrival patterns. In this paper, we present an adaptive load balancing algorithm,w...

The focus of this work is to revise for semi-batch and continuous operations, the model equations of a seeded batch cooling crystallisation of α-lactose monohydrate. A case study of evaporative semi-batch operation is also included for reference as models of cooling and heating are not much different. In order to achieve the highest yield, dynamic optimisations must be performed on these models...

This article deals with the qualitative modelling of batch production plants. The approach held is Petri net based. First a definition of a three-level net formalism is presented; the formalism extends the Valk’s approach of nets in nets in which the tokens are other nets; in this extension the lower level net handles symbolic tokens. Then a methodology for the modelling of batch processes is p...

In many queueing systems the server processes several customers simultaneously. Although the capacity of a batch, that is the number of customers that can be processed simultaneously, is often variable in practice, nearly all batch-service queueing models in literature consider a constant capacity. In this paper, we extend previous work on a batch-service queueing model with variable server cap...

Web services from search to games to stock trading impose strict Service Level Objectives (SLOs) on tail latency. Meeting these objectives is challenging because the computational demand of each request is highly variable and load is bursty. Consequently, many servers run at low utilization (10 to 45%); turn off simultaneous multithreading (SMT); and execute only a single service — wasting hard...