This paper considers a single-item, periodic-review inventory model with linear ordercosts, a convex function representing expected one-period costs, nonegative i.i.d. demandsand a fixed cost for order. Stockouts are ...This paper considers a single-item, periodic-review inventory model with linear ordercosts, a convex function representing expected one-period costs, nonegative i.i.d. demandsand a fixed cost for order. Stockouts are backordered. All data are stationary Both finiteand infinite horizon problems are treated.展开更多
The authors performed economic assessment of producing biodiesel at pilot scale using used cooking oil as feed-oil in a Bio-Pro 380 EX biodiesel reactor. The overall results suggest that the biodiesel production using...The authors performed economic assessment of producing biodiesel at pilot scale using used cooking oil as feed-oil in a Bio-Pro 380 EX biodiesel reactor. The overall results suggest that the biodiesel production using used cooking oil is a viable project even at large or medium scale. The payback period for producing biodiesel at a pilot scale of 31,320 liters per year was 1.5 years, which was 1 month longer than the payback period for a large plant capacity of 66,000 liters per year. The study demonstrated that the unit selling price and unit production cost are sensitive to the economic feasibility of biodiesel production, since price variations of BWP 1 result in at least a 13% increase and 12% decrease in profit, respectively. The study further revealed that feed-oil (used cooking oil) was the most expensive among all the inputs accounting for 61%, followed by methanol and direct labour with 19% and 13% respectively. The overall energy recorded to produce approximately 360 liters of biodiesel contributed to 2% only, suggesting that Bio-Pro 380 EX biodiesel reactor is relatively a low energy intensity processor. The situation is suitable for the promotion of biodiesel particularly in countries where initiatives to stimulate the development of biofuels are at its infant stage Botswana included.展开更多
文摘This paper considers a single-item, periodic-review inventory model with linear ordercosts, a convex function representing expected one-period costs, nonegative i.i.d. demandsand a fixed cost for order. Stockouts are backordered. All data are stationary Both finiteand infinite horizon problems are treated.
文摘The authors performed economic assessment of producing biodiesel at pilot scale using used cooking oil as feed-oil in a Bio-Pro 380 EX biodiesel reactor. The overall results suggest that the biodiesel production using used cooking oil is a viable project even at large or medium scale. The payback period for producing biodiesel at a pilot scale of 31,320 liters per year was 1.5 years, which was 1 month longer than the payback period for a large plant capacity of 66,000 liters per year. The study demonstrated that the unit selling price and unit production cost are sensitive to the economic feasibility of biodiesel production, since price variations of BWP 1 result in at least a 13% increase and 12% decrease in profit, respectively. The study further revealed that feed-oil (used cooking oil) was the most expensive among all the inputs accounting for 61%, followed by methanol and direct labour with 19% and 13% respectively. The overall energy recorded to produce approximately 360 liters of biodiesel contributed to 2% only, suggesting that Bio-Pro 380 EX biodiesel reactor is relatively a low energy intensity processor. The situation is suitable for the promotion of biodiesel particularly in countries where initiatives to stimulate the development of biofuels are at its infant stage Botswana included.
