This paper develops a method for solving the single product multi-period production-planning problem, in which the production and the inventory costs of each period arc concave and backlogging is not permitted. It is also assumed that the unit variable cost of the production evolves according to a continuous time Markov process. We prove that this production-planning problem can be Stated as a ...

Biological hydrogen production by anaerobic bacterium, Rhodospirillum rubrum was studied in batch and continuous bioreactors using synthesis gas (CO) as substrate. The systems were operated at ambient temperature and pressure. Correlations available in the literature were used to estimate the gas-liquid mass transfer coefficients (KLa) in batch reactor. Based on experimental results for the con...

A constraint is a limitation or a restriction that poses a threat to the performance and efficiency of a system. This paper presented a tactical review approach to production constraints modeling. It discussed the theory of constraints (TOC) as a thinking process and continuous improvement strategy to curtail constraints in other to constantly increase the performance and efficiency of a system...

Sodium carbonate (commonly called as soda ash or washing soda) is the primary product of the chemical industry since the year one. It was used in antiquity for the manufacture of soap and glass, using the mineral appears in some lakes of Africa, Asia and North America being a natural soda, so-called trona (Na2CO3·NaHCO3·2H2O). In Europe, the most important was the soda ash produced in Spain, No...