14 research outputs found
Optimal Wind Bidding Strategies in Day-Ahead Markets
This paper presents a computer application for wind energy bidding in a day-ahead electricity market to better accommodate the variability of the energy source. The computer application is based in a stochastic linear mathematical programming problem. The goal is to obtain the optimal bidding strategy in order to maximize the revenue. Electricity prices and financial penalties for shortfall or surplus energy deliver are modeled. Finally, conclusions are drawn from an illustrative case study, using data from the day-ahead electricity market of the Iberian Peninsula
The effect of commercial functional food with probiotics on microorganisms from early carious lesions.
Caries rates in school-age children are still high enough to be the cause of serious concern for health systems in different countries. The biotechnology strategies studied to decrease these rates include the consumption of probiotics-available via a variety of functional foods obtainable on the market-that are able to inhibit bacteria associated with this disease. In this vein, the purpose of this study was to determine the effect of these foods on the growth of microorganisms in early carious lesions in children aged between 6 and 12. In the first phase, an agar well diffusion method was applied to selected foods, available in supermarkets, which contain probiotics that have already been shown to inhibit Streptococcus mutans (ATCC 25175), and to lower the pH in liquid culture media. In a second phase, these foods (n = 4) were examined in terms of their ability to inhibit the microorganisms in contact with early carious lesions in children and to reduce the pH of mixed cultures combined with the food. The results revealed that, of the foods tested, three inhibit the growth of microorganisms in carious lesions and, at the same time, lower the pH of the culture by more than 2.5 units. The food with the highest inhibitory capacity (14 mm, IQR 13-14) showed a similar effect among patients (P > 0.05), which together with the fact that its sugar concentration is less than 10%, makes it an ideal candidate for clinical study.0000-0002-5435-3456maria.angaritad@[email protected]
Optimal Bidding Strategies of Wind-Thermal Power Producers
Part 14: Optimization in Energy ManagementInternational audienceThis paper addresses a stochastic mixed-integer linear programming model for solving the self-scheduling problem of a thermal and wind power producer acting in an electricity market. Uncertainty on market prices and on wind power is modelled via a scenarios set. The mathematical formulation of thermal units takes into account variable and start-up costs and operational constraints like: ramp up/down limits and minimum up/down time limits. A mixed-integer linear formulation is used to obtain the offering strategies of the coordinated production of thermal and wind energy generation, aiming the profit maximization. Finally, a case study is presented and results are discussed