Green's functions on finite lattices and their connection to the infinite lattice limit

It is shown that the Green's function on a finite lattice in arbitrary space dimension can be obtained from that of an infinite lattice by means of translation operator. Explicit examples are given for one- and two-dimensional lattices

A smart material based approach to morphing

This presentation gives an overview of the Shape Memory Alloy (SMA) based approach to the research and13; development of adaptive/smart/morphing airframe structural technologies at the Advanced Composites13; Division, NAL. Central to this approach is the efficient integration of thermal NiTi SMA elements with13; polymeric carbon composites. The SMA elements could be either externally placed or embedded in the13; polymeric composite. The external connection could be in the form of mechanisms / devices

Development and Wind Tunnel Evaluation of a SMA Based Trim Tab Actuator for a Civil Aircraft

This paper presents about the development and wind tunnel evaluation of an SMA based smart trim tab for a typical 2 seater civil aircraft. SMA actuator was housed in the port side of the elevator for actuating the trim tab. Wind tunnel tests were conducted on a full scale Horizontal Tail model with Elevator and Trim Tab at free stream speeds of 25, 35 & 45 m/sec and also for a number of deflections of the elevator (30° up, 0° neutral & 25° down) and trim-tab 11° & 21° up and 15° & 31° down). To measure the hinge moment experienced by the trim-tab at various test conditions, two miniaturized balances were designed and fabricated. Gain scheduled proportional integral controller was developed to control the SMA actuated smart trim tab. It was confirmed during the tests that the trim-tab could be controlled at the desired position against the aerodynamic loads acting on it for the various test conditions

ELEVEN LEVEL INVERTER DESIGN WITH DVR FOR DISTRIBUTION ENERGY SYSTEM

 In this paper with flexible AC transmission system capability is implemented. The proposed inverter is placed between the wind turbine and the grid, same as a regular WEI, and is able to regulate active and reactive power transferred to the grid. This inverter is equipped with dynamic voltage restorer option in order to control the power factor  of  the local feeder lines. The goal of this project is to introduce new ways to increase the penetration of renewable energy systems into the distribution systems. This will encourage the utilities and customers to act not only as a consumer, but also as a supplier of energy.Â

Predictive modelling of topology and loop variations in dimeric DNA quadruplex structures.

We have used a combination of simulated annealing (SA), molecular dynamics (MD) and locally enhanced sampling (LES) methods in order to predict the favourable topologies and loop conformations of dimeric DNA quadruplexes with T2 or T3 loops. This follows on from our previous MD simulation studies on the influence of loop lengths on the topology of intramolecular quadruplex structures [P. Hazel et al. (2004) J. Am. Chem. Soc., 126, 16 405-16 415], which provided results consistent with biophysical data. The recent crystal structures of d(G4T3G4)2 and d(G4BrUT2G4) (P. Hazel et al. (2006) J. Am. Chem. Soc., in press) and the NMR-determined topology of d(TG4T2G4T)2 [A.T. Phan et al. (2004) J. Mol. Biol., 338, 93-102] have been used in the present study for comparison with simulation results. These together with MM-PBSA free-energy calculations indicate that lateral T3 loops are favoured over diagonal loops, in accordance with the experimental structures; however, distinct loop conformations have been predicted to be favoured compared to those found experimentally. Several lateral and diagonal loop conformations have been found to be similar in energy. The simulations suggest an explanation for the distinct patterns of observed dimer topology for sequences with T3 and T2 loops, which depend on the loop lengths, rather than only on G-quartet stability

Inhibitor for the Corrosion of Mild Steel in H2SO4

An extract of Terminalia chebula fruits was investigated as a corrosion inhibitor of mild steel in 0.5 M H2SO4 by means of conventional mass loss, electrochemical polarization, electrochemical impedance spectroscopy and scanning electron microscopy. The mass loss results showed that the extract of Terminalia chebula is an excellent corrosion inhibitor, electrochemical polarization data revealed the mixed mode of inhibition and the results of electrochemical impedance spectroscopy showed that the change in the impedance parameters, charge transfer resistance and double layer capacitance with the change in concentration of the extract is due to the adsorption of active molecules leading to the formation of a protective layer on the surface of mild steel. Scanning electron microscopic studies provided confirmatory evidence of an improved surface condition, due to adsorption, for corrosion protection.Keywords: Terminalia chebula, acid corrosion inhibitor, electrochemical polarization, electrochemical impedance spectroscopy, mild stee