We consider a firm that periodically procures raw material units, stores them, and processes them into finished products upon order arrivals. The raw material cost evolves in a Markovian fashion, whereas the demand process is influenced by both the raw material cost and sales prices charged by the firm. The firm controls both the raw material procurement activity and sales price in each period....

slurries of rice-straw cellulose (obtained by delignification and removal of hemicelluloses from the powdered raw material) were subjected to ultrasonic waves at different intensities for various times (constant temperature). susceptibility of the samples to cellulose-hydrolysis increased initially with pretreatment time, reaching a maximum or a constant level thereafter. maximum glucose yield ...

Resource productivity, measured as GDP output per resource input, is a widespread sustainability indicator combining economic and environmental information. Resource productivity is ubiquitous, from the IPAT identity to the analysis of dematerialization trends and policy goals. High resource productivity is interpreted as the sign of a resource-efficient, and hence more sustainable, economy. It...

The production of mineral nitrogen represents a large fossil energy input in Swedish agriculture. However, mineral nitrogen can be produced in the Haber-Bosch synthesis, with input from renewable energy. This could lower the dependency on fossil energy and the emissions of greenhouse gases in agricultural production. The aim of this study was to investigate the land use, energy use and greenhou...

Reliable isolated energy systems are necessary for supplying energy to remote areas where grid extension is not feasible. It may also be required to harness renewable energy to reduce the use of conventional fuel that involves potentially high transportation cost and carbon emissions. Polygeneration systems are suitable for distributed energy supply in remote areas with the advantages of compac...