Ant colony optimization (ACO) has previously been applied to the Minimum Weight Vertex Cover Problem with very good results. The performance of the ACO algorithm can be improved with the use of different variations of the basic Ant Colony System algorithm, like the use of Elitism, Rank based approach and the MinMax system. In this paper, we have made an analysis of effectiveness of these variat...

The dynamics of the PYP photocycle have been studied using time-resolved optical rotatory dispersion (TRORD) spectroscopy in the visible and far-UV spectral regions to probe the changes in the chromophore configuration and the protein secondary structure, respectively. The changes in the secondary structure in PYP upon photoisomerization of the chromophore can be described by two exponential li...

In a recent study on the optical rotatory dispersion of proteins with improved spectropolarimetric techniques, the negative Cotton effect with the trough in the optical rotatory dispersion curves at 233 rnp was investigated (1). According to Simmons, Blout, et al. (2, 3), the amplitude of this effect is related to the amount of the a-helical conformation. The same seems to be true of the positi...

In this paper, a new structure is provided for the dispersion compensating photonic crystal fibers in order to broaden the chromatic dispersion and increase the dispersion compensating capability in a wide wavelength range. In the structure, putting elliptical holes in the first ring of the inner core clad of a dispersion compensating fiber of the hexagonal lattice, increases the wavelength ran...

Solid polymer-drug dispersions are used to prepare and stabilize amorphous forms of poorly soluble drugs as a means of improving drug solubility, dissolution and bioavailability. Despite many reports on this subject, solid dispersion dissolution mechanisms have not been well understood. An early study was reported by Simonelli, Mehta and Higuchi (SMH) in 1969 and has served as a model for dispe...

A new hybrid methodology that fully integrates the processing capabilities of the twin screw extrusion process (conveying solids, melting, dispersive and distributive mixing, pressurization, temperature profiling, devolatilization) with electrospinning is described. The hybrid process is especially suited to the dispersion of nanoparticles into polymeric binders and the generation of nanopartic...

In this paper, experimental and Finite Element Methods have been used to determine mechanical properties of nanocomposites. Standard tensile and compression samples with 0.0, 0.15, 0.25, 0.35, 0.45, and 0.55 weight fraction of Multi-Walled Carbon Nanotube (MWCNT) were prepared and tested. Nanotube weight fraction was varied to investigate the effects of nanotube weight fraction on nanocomposite...