The paper addresses an inventory model of pharmaceutical products where the demand rate of the customers increases with the volume of the initiatives of the sales team. In this model, the deterioration of the product varies depending on on-hand inventory. The volume of sales team initiatives is a control variable. It is dependent on on-hand inventory and vice versa. The profit function of the f...

In sea cage fish farming, production quotas aim to constrain the impact of fish farming on the surrounding ecosystem. It is unknown how these quotas affect economic profitability and environmental impact of genetic improvement. We combined bioeconomic modelling with life cycle assessment (LCA) to calculate the economic (EV) and environmental (ENV) values of thermal growth coefficient (TGC) and ...

On a typical dairy farm today, large amounts of N are imported as feed supplements and fertilizer. If this N is not recycled through crop growth, it can lead to large losses to the atmosphere and ground water. More efficient use of protein feed supplements can potentially reduce the import of N in feeds, excretion of N in manure, and losses to the environment. A simulation study with a dairy fa...

The present paper investigates how a storage unit, coupled with a wind farm could influence the economic operation of the power system. For this reason two optimization algorithms are implemented, where the storage capacity is assigned certain costs and is able to vary in size. The objective of the first optimization is to identify the optimal power infeed as well as the necessary battery capac...

This simulation study was to evaluate low cost feeding strategies in response to higher cost of commercial concentrates to maintain current milk sales from dual purpose cattle herds in the humid lowlands of western Venezuela. Data were from farm surveys in 1987 and 1988. Baseline net margins from milk and beef per cow per year were $132 and $99 for two farm cases with average dally milk of 10 a...

The continuous evolvement of dairy industry in countries like New Zealand, with increased dairy conversions and intensification, has resulted in remarkable economic development, though at the cost of environmental degradation. The increasing use of nitrogen fertilizers to sustain increasing number of cows has increased the risk of enhanced nitrate leaching and methane and nitrous oxide emission...

Dairy sires were ranked for overall merit by an average daughter's contribution to farm net profit. Biological characteristics of sires and economic factors of a dairy farm were linked by linear programming. Availability and constraints of resources were in the model. Average daughter's returns over variable costs attributable to sire proofs for several traits was the measure of sire's net meri...

the effects of cutting subsidy on broiler production in kerman province were investigated after privitization. in this regard a random sample of 32 poultry farms in kerman were chosen and the farmers were interviewed. the unit- output - price profit function model was used to determine the supply and demand elasticity of broider products. the results show that the profit of poultry farms increa...