Árbók VFÍ/TFÍ - 01.06.1998, Blaðsíða 325
Optimization Models of Aquaculture Operations 323
In this paper two size structured optimization models for production planning in a
salmon farm were presented. A Markov model approach was used to represent the growth
and the evolution of the size distributions in each pen throughout the growing period. The first
of the two models is a Linear Programnting model for analyzing long term production strat-
egy. In the second model integer variables assure that harvesting schedules are in accordance
with the harvest selection practice of the company in question. The Mixed Integer
Programming model proposed can be used for short term scheduling of partial or full har-
vesting from individual pens.
The results of the optimization are suggestions with respect to harvest plans in order to
target the price peaks with the right size of fish so profit is maximized for the farm. Tra-
ditionally, aquaculture has been production-driven, i.e. governed by what the farmer could
produce, whether on an international or local level. This study is hoped to be a step towards
the goal of changing this, so that aquaculture companies become more market-driven. By
having the models proposed in this paper, the enterprise can analyze production strategies
and find the strategy where the production is better targeted to the market requirements.
The linking between farming and value adding processing of fish to produce the final
products demanded by the market is gaining increased attention in aquaculture. A natural
continuation of this study would be to connect it with a model to optimize the product mix
in fish processing, see Jensson (1988).
Acknowledgements
The author would like to thank Mr William Robertsson and Mr Victor Bradford at Heritage
Aquaculture, Connors Brothers Ltd, Blacks Harbour, New Brunswick, and in particular Pro-
fessor Eldon A. Gunn at the Department of Industrial Engineering, DalTech-Dalhousie Uni-
versity in Halifax, Nova Scotia, for their valuable assistance, co-operation and comments.
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