Adaptive Utilization of Optical Variables During Postural and Suprapostural Dual-Task Performance: Comment on Stoffregen, Smart, Bardy, and Pagulayan (1999).

T. A. Stoffregen, L. J. Smart, B. G. Bardy, and R. J. Pagulayan (1999) combined a postural task (upright stance) with a suprapostural task (visual fixation) to show that sway variability was not driven by optic flow in a task-independent manner (autonomous control) but governed by the demands of the supra-postural task (facilitatory control). The present study used a novel combination of Stoffregen et al.'s task conditions but obtained clear evidence of autonomous control and no indication of facilitatory control. The theoretical adequacy of the stabilization-by-looking versus stabilization-of-looking contrast was examined, as was emerging evidence that posture control and common cognitive tasks place concurrent demands on the same capacity-limited resources. An adaptive resource-sharing view of postural-suprapostural multitasking was proposed as an alternative to both the autonomous- and facilitatory-control views. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development on astable multivibrators using the combination of linear and non-linear materials as switching elements based on all optial method

In this communication we propose a method to implement an all-optical astable multivibrator using the non-linear material based switches and logic gates. The scheme can operate in real time. The delay time can achieve ps(pico-second). The pulse duration can be made very low and may cross the THz easily by selecting proper material and laser source.     

A primary unit commitment approach with a modification process

This paper introduces an approach to one of the most important problems in electrical power system called the Unit Commitment (UC). The proposed method PUC-MP which stands for the primary unit commitment-modification process, addresses this problem firstly by using a simple and new priority for operating the generating units in each hour, and then, using a modification process which enhances the solution quality with lower cost. The PUC-MP takes advantage of both deterministic and stochastic algorithms in its structure to solve the discrete-variable part of the UC problem for choosing a suitable combination of units in each hour, and also, continuous-variable part of it which is dispatching the operating units’ output power to the power network load economically. The latter part which is called economic dispatch (ED) has been solved using an intelligent algorithm which in turn has been customized by two new ideas to increase its efficiency. Simulation results show that this new approach even without using its modification process can be considered as an effective approach which surpasses some other popular and recently reported methods in producing near-optimal and robust solutions.     

Time evolution of entanglement and bistability of two coupled quantum dots in a driven cavity

Abstract

The time evolution of entanglement between two quantum dots (QDs) trapped inside a cavity driven by a coherent quantized field is studied. In the presence of dissipation, entanglement shows many interesting features such as sudden death and revival, and finite steady state value after sudden death. We also investigate dependence of entanglement on dot variables and its relation to bistability. It is found that entanglement vanishes when the cavity field intensity approaches the upper branch of the bistability curve. When the cavity is driven by a modulated field in the presence of dissipation, it can periodically generate entanglement, which is much larger than the maximum value attained in the steady-state for this system but the dots are never fully entangled.     

Effect of Starting As-cast Structure on the Microstructure–Texture Evolution During Subsequent Processing and Finally Ridging Behavior of Ferritic Stainless Steel

Metallurgical and Materials Transactions A - Effect of the initial as-cast structure on the microstructure–texture evolution during thermomechanical processing of 409L grade ferritic...     

Barium cobaltite nanoparticles: Sol-gel synthesis and characterization and their electrochemical hydrogen storage properties

The study of the effect of different chelating agents in the Pechini method on the morphology has been a promising strategy that can be used for practical tuning of the nanoparticle's morphology and hence the electrochemical hydrogen storage capacity. In the current study, the conventional Pechini sol-gel approach was used to prepare the Ba₂Co₉O₁₄ nanoparticles as a novel hydrogen storage material. The X-ray diffraction investigation approved the formation of Ba₂Co₉O₁₄ with a Hexagonal crystal structure for all of the synthesized samples. The scanning electron microscopy (SEM) revealed when citric acid was used as a chelating agent, nanoparticles with finer and more uniform morphology were obtained rather than other chelating sources. The transmission electron microscopy (TEM) showed in the presence of citric acid; the size of the synthesized nanoparticles was between 14 and 24 nm. According to the Diffuse Reflectance Spectroscopy (DRS) analysis, the calculated bandgap of synthesized nanoparticles was approximately 3.2 eV, which indicates that synthesized nanoparticles were semiconductors in essence. The electrochemical hydrogen adsorption/desorption results showed that the sample synthesized by the citric acid has an enhancement in electrochemical hydrogen storage of approximately 800 mAh/g after 15 cycles.     

Green synthesis and characterization of RGO/Cu nanocomposites as photocatalytic degradation of organic pollutants in waste-water

Recently, nanocomposite photocatalysts based on semiconductors have attracted much attention due to their suitable bandgap. Combination of tow of several semiconductors can slow down the electron-hole recombination. In this regard, we have depicted an eco-friendly and green fabrication technique to synthesize RGO/Cu nanocomposite by the reduction of graphene oxide and Cu²⁺ ion utilizing spearmint extract as a reductant and capping agent. The sample was identified by FTIR, XRD, FESEM, EDS, HRTEM, and CV. The results of photocatalytic performance revealed that RGO/Cu is an efficient catalyst for degrading organic pollutants. This compound can eliminate Rhodamine B (RhB) and Methylene blue (MB) 91.0% and 72.0%, respectively.     

Friedmann-Robertson-Walker metric in curvature coordinates and its applications

For the first time, we express the general Friedmann-Robertson-Walker (FRW) metric (k = +1, 0,?1) into explicit “Schwarzschild” or “Curvature” form, which is important from the viewpoint of cosmology. With this form of the FRW metric, we reconsider the old problem of embedding a Schwarzschild mass (SM) in a pre-existing FRW background from the viewpoints of both (1) the enigmatic McVittie metric, obtained in 1933 and (2) the Einstein-Straus approach (1945) of scooping out a spherical cavity in the same background. Since the exterior of the SM is, by definition, described in the Schwarzschild coordinates, for a definitive study of the Einstein-Straus approach we employ this form of the FRW metric. We find that a necessary condition for a SM to participate in the cosmic expansion is that the background fluid is dust.