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Eye Gaze Controlled MFD for Military Aviation
No full textMulti-Function Displays (MFD) are essential part of glass cockpit of modern military and civilian aircrafts. They can display more information in less space than traditional analog displays. Interacting with MFDs is still now limited to a joystick system attached to throttle (called Target Designation System, TDS). This paper explored using gaze controlled interface for MFD and proposed two algorithms based on hotspots and adaptable zooming for improving response times in a gaze controlled interface. Three user studies confirmed gaze controlled MFD can significantly reduce response times for big peripheral buttons compared to touchscreen in a head down configuration and compared to existing TDS in a head up configuration
Correlation between photoemissive and morphological properties of KBr thin film photocathodes
No full textIn the present work, the morphological properties of KBr photocathodes are correlated with their photoemissive behavior using a combination of analyzing techniques including SEM, TEM and AFM. From morphological studies, it is observed that KBr films have granular characteristics with varied average grain size and grain density. Structure and orientation of individual grains have been investigated by selected area electron diffraction technique and found to be the crystalline in nature with a face centered cubic structure. It is evident from the AFM analysis that the root mean square roughness and maximum area peak height have been decreased with the deposition of more KBr layers. The photoemission studies reveal that the resultant photocurrent is enhanced with increasing film thickness and it is directly related to the surface area coverage and grain density. (C) 2017 Elsevier B.V. All rights reserved
Maximal entanglement and state transfer using Arthurs-Kelly type interaction for qubits
No full textWe study entanglement generation between a system qubit and three apparatus qubits using an exactly solvable Arthurs-Kelly type model. We demonstrate the possibility of generating an EPR-like maximally entangled system-apparatus state, in which the second qubit of the usual EPR state is replaced by a three qubit state. We design a very simple protocol to transfer the unknown state of the system onto one of the apparatus qubits which can then be sent elsewhere via a quantum channel. This protocol can be seen as an alternative teleportation scheme
A thermo-visco-plastic damage model and SPH simulations of plugging failure
No full textA thermo-visco-plasticity model, recently developed based on a microinertia driven dynamic flow rule, is exploited to account for damage due to fracture. This is accomplished by adjoining the equations for thermo-visco-plasticity, herein discretized through the smooth particle hydrodynamics (SPH), with a ``pseudospring'' based discrete damage model. In treating ductile fractures, this coupled material model accounts for the inertia associated with moving microstructural defects and time lags for the dissipative fluxes to attain the steady state. In this approach, while the microinertia-driven flow rule provides a vehicle to evolve plastic strain, pseudosprings are exploited to treat material damage and the resulting reduced force transfer. The current scheme does not necessitate the introduction of a yield or damage surface in evolving the plastic-strain/damage parameters, and thus the numerical implementation avoids a computationally intensive return mapping. We demonstrate the performance of the proposed model through SPH-based numerical simulations and also undertake a validation exercise against experimental observations from gas-gun penetration tests on an 8-mm thick Weldox 460 E steel plate
Signatures of Topological Superconductivity in Bulk-Insulating Topological Insulator BiSbTe1.25Se1.75 in Proximity with Superconducting NbSe2
No full textThe combination of superconductivity and spin-momentum locking at the interface between an s-wave superconductor and a three-dimensional topological insulator (3D-TI) is predicted to generate exotic p-wave topological superconducting phases that can host Majorana Fermions. However, large bulk conductivities of previously investigated 3D-TI samples and Fermi level mismatches between 3D bulk superconductors and 2D topological surface states have thwarted significant progress. Here, we employ bulk-insulating topological insulators in proximity with two-dimensional superconductor NbSe2 assembled via van der Waals epitaxy. Experimentally measured differential conductance yields unusual features including a double-gap spectrum, an intrinsic asymmetry that vanishes with small in-plane magnetic fields, differential conductance ripples at biases significantly larger than the superconducting gap. We explain our results on the basis of proximity-induced superconductivity of topological surface states, while also considering possibilities of topologically trivial superconductivity arising from Rashba-type surface states. Our work demonstrates the possibility of obtaining p-wave superconductors by proximity effects on bulk-insulating TIs
Conical intersections involving the lowest (1)pi sigma* state in aniline: Role of the NH2 group
No full textAt low excitation energies of under 5 eV, conical intersections (CIs) involving the lowest three electronic states of aniline, viz. the (1)pi pi*/(1)pi sigma* and (1)pi sigma*/GS intersections, are accessible. Signatures of ultrafast dynamics, including H atom loss, are observed experimentally with energies above the (1)pi sigma* threshold. Ab initio results corroborate the view that the intersections are involved in the rapid population flow. In the present computational study, we characterize these intersections using the CASSCF and XMS-CASPT2 methods. We locate the CIs and analyse the important vibronic couplings at these geometries from a normal mode as well as an NH2 local mode perspective. Through our findings, we suggest that modes largely local to the NH2 group couple the electronic states the strongest at these intersections. (C) 2018 Elsevier B.V. All rights reserved
Identification of Conotoxins with Novel Odd Number of Cysteine Residues from the Venom of a Marine Predatory Gastropod Conus leopardus Found in Andaman Sea
No full textBackground: Conotoxins are neuro-pharmacologically active cysteine rich peptides isolated from the venom complex of marine cone snails. These are usually made of even number of cysteines. Method: In this study we characterised six novel conotoxin sequences from the venom of Conus leopardus collected from the Andaman Sea, namely Le907 (C-C), Le868 (C-C), Le933 (-C-CC), Le949 (-C-CC), Le1988 (C-C-CC-C) and Le1642 (CC-C-C) using de novo mass spectrometry-based sequencing methods. Astonishingly 3 of these peptides possess novel arrangements of cysteine residues with odd number of cysteines (-C-CC; C-C-CC-C), namely Le933, Le949 and Le1988. Further, a post-translational variant of peptide Le933 was identified and experimentally determined to contain hydroxyproline. Results: The unusual cysteine arrangements observed suggests novel class of conotoxins. These results expand our understanding of the diversity of odd cysteine arrangements in conotoxins
Bounds and joint estimators for channel, phase noise, and timing error in communication systems using statistical framework
No full textBounds and joint estimators for channel and phase noise, together with timing error in the communication systems are described in this paper. We consider the wireless communication systems using Orthogonal Frequency Division Multiplexing (OFDM) with Multiple Input Multiple Output (MIMO) techniques. A MIMO-OFDM system having the influence from impairments of the channel, timing, and phase is modeled. Also, a modified signal model is developed, with the timing error embedded in the channel. Derivation of Bayesian bounds for the estimation error is done. We propose a joint Bayesian estimator for channel and phase noise with timing ambiguity in a MIMO-OFDM single-user communication system. A modified algorithm with low complexity is also developed. The analysis of the estimation performance variation due to change in the number of antennas is done. Further, the consequence of channel statistics and noise information inaccuracy on estimator performance is analyzed. (C) 2018 Elsevier Ltd. All rights reserved
Event shape variables measured using multijet final states in proton-proton collisions at root s=13 TeV
No full textThe study of global event shape variables can provide sensitive tests of predictions for multijet production in proton-proton collisions. This paper presents a study of several event shape variables calculated using jet four momenta in proton-proton collisions at a centre-of-mass energy of 13 TeV and uses data recorded with the CMS detector at the LHC corresponding to an integrated luminosity of 2.2 fb(-1). After correcting for detector effects, the resulting distributions are compared with several theoretical predictions. The agreement generally improves as the energy, represented by the average transverse momentum of the two leading jets, increases
Improved Well-Conditioned Model Order Reduction Method Based on Multilevel Krylov Subspaces
No full textReduced order models (ROMs) based on the asymptotic waveform evaluation enable fast and efficient parametric analysis of large-scale matrix systems exhibiting nonlinear dependence on certain desired parameter(s). However, they are known to be narrowband due to the inherently ill-conditioned moment generation process. While well-conditioned approaches exist that enforce the moment-matching criteria by introducing some correction terms, these are not optimal and are difficult to parallelize. This letter introduces a well-conditioned multilevel Krylov model order reduction (WMKMOR) technique which is accurate over a larger band and faster to set up than existing approaches. Also, the multiple levels of Krylov subspaces in WMKMOR are generated independently. The improvement in ROM bandwidth using this technique is demonstrated for a finite-element model of an electromagnetic scattering example