A novel approach is proposed to design optimal finite word length (FWL) realizations of digital controllers implemented in fixed-point arithmetic. An analytical method is first formulated to obtain a global optimal controller realization that optimizes an FWL closed-loop stability measure. Since this FWL closed-loop stability measure is solely linked to the fractional part or precision of fixed...

A general approach to real-time transient stability control is described, yielding various complementary techniques: pure preventive, open loop emergency, and closed loop emergency controls. The organization of the resulting control schemes is then revisited in order to make it able to cover static and voltage security, in addition to transient stability. Distinct approaches for preventive and ...

Fifteen RNA hairpins that share the same stem sequence and have homopolymer loops of A, C and U residues which vary in length from three to nine nucleotides were synthesized and their thermal stabilities determined. Tm varies as a function of loop size but is almost independent of loop composition. Loops of four or five nucleotides are found to be the most stable loop size. This is consistent w...

The question of transient stability control is revisited, various types of controls are identified, and a general approach to closed-loop emergency control is proposed. The focus is on feasibility aspects, general salient features and illustration of stabilization capabilities of an emergency control scheme relying on generation shedding.

In this paper, we consider the robust stability analysis and synthesis problems for closed-loop vibrational control. In the analysis problem, we derive an upper bound on the allowable unstructured uncertainty which preserves the stability of a closed-loop vibrationally stabilized system. In the synthesis problem, we establish a necessary and sufficient condition for the existence of a single vi...

In this paper, for the first time to our knowledge, we investigate the optical bi-stability in a compact parallel array of micro- ring resonators with 5μm radius, induced by optical nonlinearity. Due to the nature of perfect light confinement, resonance and accumulation process in a ring resonator, optical nonlinear effects, even at small optical power of a few milliwatts in this structure are ...

In type-II string theory compactifications on Calabi-Yau manifolds, topological string theory partition functions give a class of exact F-terms in the four dimensional effective action. We point out that in the background of constant self-dual field strength, these terms deform the central charges for D-branes wrapping Calabi-Yau manifold to include string loop corrections. We study the corresp...