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The paper presents an approach for identifying the most effective Flexible AC Transmission System (FACTS) Controllers, locations, types and ratings that increase asset utilization of power systems. The approach is a combined static/dynamic procedure based on the use of a continuation power flow, an optimal power flow and an eigenvalue analysis. The application of this approach on a representative studied transmission system has resulted in an increase of the maximum stable loadability limit by 6.7%. The paper finally shows that the proposed approach is helpful in coordinating the functionality of FACTS Controllers to enhance power system dynamics. Keywords: FACTS Controllers, HVdc Transmission, Voltage Collapse, Electromechanical Stability

Highlights: [•] Higher fracture energy and toughness were observed for a higher displacement rate. [•] Lowering temperature fracture energy and toughness increment. [•] A power law well describes the cross-head displacement rate influence. [•] A linear equation represents with good accuracy the temperature influence. [Copyright &y& Elsevier]

The determination of some inherent optical properties can be addressed by estimating the ocean chlorophyll concentration, if bio-optical models can be applied - such as for the offshore sea water. This inverse problem can be formulated as an optimization problem and iteratively solved, where the radiative transfer equation is the direct model. An objective function is given by the square difference between computed and in situ experimental radiances at every iteration. In the standard ant colony optimization (ACO), the pheromone is reinforced only on the best ant of the population. The fuzzy strategy consists in including additional pheromone quantity on the best ant, but a small pheromone quantity is also spread over the other solutions close to the best one. Test results show that the fuzzy-ACO produces better inverse solutions. [ABSTRACT FROM AUTHOR]

A simple, rapid, sensitive, reproducible, and accurate reversed-phase HPLC procedure is proposed for the determination of sodium benzoate in quince jam samples. The sample preparation was simple, involving only extraction with methanol. The chromatographic separation was achieved using a reversed-phase column Spherisorb ODS2 (5μm; 25.0 × 0.46 cm). Gradient elution was carried out using water-formic acid (19:1) (A) and methanol (B). The effluent was monitored by a diode-array detector and chromatograms were recorded at 280 nm. The detection limit value of the method for sodium benzoate was 0.5 μg/mL and the method was precise (SD=0.003; CV%=2.76; n=6). Recovery values of sodium benzoate from spiked quince jam samples were between 94.7 and 100 %. This technique can also be useful for the simultaneous definition of the phenolic profile (phenolic acids, flavonoids, and glycosides of procyanidin polymers) of quince jam. [ABSTRACT FROM AUTHOR]