The energy required to crush rocks is proportional to the amount of new surface area that is created; hence, a very important percentage of the energy consumed to produce construction aggregates is spent in producing non-commercial fines. Data gathered during visits to quarries, an extensive survey and laboratory experiments are used to explore the role of mineralogy and fracture mode in fines ...

In this research, a bi-objective model is developed to deal with a supply chain including multiple suppliers, multiple manufacturers, and multiple customers, addressing a multi-site, multi-period, multi-product aggregate production planning (APP) problem. This bi-objective model aims to minimize the total cost of supply chain including inventory costs, manufacturing costs, work force costs, hir...

We consider the problem of dynamically allocating scarce resources to multiple projects in a project-oriented production system such as a naval shipyard. We formulate axioms governing the relationship between resource allocations and work progress of aggregate project activities, from which a model of project execution is derived. This model is more accurate than models which represent aggregat...

Expression of recombinant proteins in Escherichia coli (E. coli) remains the most popular and cost-effective method for producing proteins in basic research and for pharmaceutical applications. Despite accumulating experience and methodologies developed over the years, production of recombinant proteins prone to aggregate in E. coli-based systems poses a major challenge in most research applica...

Batch processing is becoming more important in the process industries, because of the increasing product variety and the decreasing demand volumes for individual products. In batch process industries it is difficult to estimate the completion time, or makespan, of a set of jobs, because jobs interact at the shop floor. We assume a situation with hierarchical production control consisting of a p...

While the conventional DEA based production plans aim to minimize all the inputs consumption and maximize all the outputs production, there are many real world production systems may also generate undesirable by-products. One methodological difficulty associated with the previous DEA-based production planning models is how to incorporate undesirable factors in the planning models, while the sim...

This paper describes the development of a hierarchical planning and scheduling system for a multiple plant, multiple product, seasonal demand situation. In this hierarchical structure, optimal decisions at an aggregate level (planning) provide constraints for detailed decision making (scheduling). Four levels of decision making are used: first, products are assigned to plants (using mixed-integ...

Tendency to optimization in last decades has resulted in creating multi-product manufacturing systems. Production planning in such systems is difficult, because optimal production volume that is calculated must be consistent with limitation of production system. Hence, integration has been proposed to decide about these problems concurrently. Main problem in integration is how we can relate pro...