Sentiment analysis by deep learning approaches

We propose a model for carrying out deep learning based multimodal sentiment analysis. The MOUD dataset is taken for experimentation purposes. We developed two parallel text based and audio basedmodels and further, fused these heterogeneous feature maps taken from intermediate layers to complete thearchitecture. Performance measures–Accuracy, precision, recall and F1-score–are observed to outperformthe existing models

Gravitational and electromagnetic fields of a charged tachyon

An axially symmetric exact solution of the Einstein-Maxwell equations is obtained and is interpreted to give the gravitational and electromagnetic fields of a charged tachyon. Switching off the charge parameter yields the solution for the uncharged tachyon which was earlier obtained by Vaidya. The null surfaces for the charged tachyon are discussed.Comment: 8 pages, LaTex, To appear in Pramana- J. Physic

Linear theory of unstable growth on rough surfaces

Unstable homoepitaxy on rough substrates is treated within a linear continuum theory. The time dependence of the surface width $W(t)$ is governed by three length scales: The characteristic scale $l_0$ of the substrate roughness, the terrace size $l_D$ and the Ehrlich-Schwoebel length $l_{ES}$. If $l_{ES} \ll l_D$ (weak step edge barriers) and $l_0 \ll l_m \sim l_D \sqrt{l_D/l_{ES}}$, then $W(t)$ displays a minimum at a coverage $\theta_{\rm min} \sim (l_D/l_{ES})^2$, where the initial surface width is reduced by a factor $l_0/l_m$. The r\^{o}le of deposition and diffusion noise is analyzed. The results are applied to recent experiments on the growth of InAs buffer layers [M.F. Gyure {\em et al.}, Phys. Rev. Lett. {\bf 81}, 4931 (1998)]. The overall features of the observed roughness evolution are captured by the linear theory, but the detailed time dependence shows distinct deviations which suggest a significant influence of nonlinearities

Nonmonotonic roughness evolution in unstable growth

The roughness of vapor-deposited thin films can display a nonmonotonic dependence on film thickness, if the smoothening of the small-scale features of the substrate dominates over growth-induced roughening in the early stage of evolution. We present a detailed analysis of this phenomenon in the framework of the continuum theory of unstable homoepitaxy. Using the spherical approximation of phase ordering kinetics, the effect of nonlinearities and noise can be treated explicitly. The substrate roughness is characterized by the dimensionless parameter $Q = W_0/(k_0 a^2)$, where $W_0$ denotes the roughness amplitude, $k_0$ is the small scale cutoff wavenumber of the roughness spectrum, and $a$ is the lattice constant. Depending on $Q$, the diffusion length $l_D$ and the Ehrlich-Schwoebel length $l_{ES}$, five regimes are identified in which the position of the roughness minimum is determined by different physical mechanisms. The analytic estimates are compared by numerical simulations of the full nonlinear evolution equation.Comment: 16 pages, 6 figures, to appear on Phys. Rev.

Optimality criteria without constraint qualications for linear semidenite problems

We consider two closely related optimization problems: a problem of convex Semi- Infinite Programming with multidimensional index set and a linear problem of Semidefinite Programming. In study of these problems we apply the approach suggested in our recent paper [14] and based on the notions of immobile indices and their immobility orders. For the linear semidefinite problem, we define the subspace of immobile indices and formulate the first order optimality conditions in terms of a basic matrix of this subspace. These conditions are explicit, do not use constraint qualifications, and have the form of criterion. An algorithm determining a basis of the subspace of immobile indices in a finite number of steps is suggested. The optimality conditions obtained are compared with other known optimality conditions

Movement of a secondary immiscible liquid in a suspension using a non-invasive technique

In this paper, the movement of a secondary immiscible liquid when added to a suspension of hydrophilic particles in a continuous hydrophobic phase is investigated. This was achieved through an approach using high speed camera and X-ray computer tomography. These non-invasive approaches allowed the secondary liquid displacement within the suspension to be monitored on the surface level and within the suspension through a time lapse of scans. The addition of a small amount of secondary liquid to suspensions, can lead to a transition from a fluid-like to paste-like structure. The kinetics taking place and responsible for this, during both short and long term storage were investigated to better understand the mechanisms taking place. Water was added as the secondary immiscible liquid to suspensions composed of sucrose (icing sugar) and sunflower oil. Different volumes of secondary liquid were added to the suspensions. The rate of movement as well as the spreading of the secondary liquid into the suspension was calculated from the scans taken. The surface area to volume ratio was proposed as a reason for the spreading of the liquid for the smaller volume droplet being greater in comparison to the larger volume droplet

Size-dependent spinodal and miscibility gaps for intercalation in nano-particles

Using a recently-proposed mathematical model for intercalation dynamics in phase-separating materials [Singh, Ceder, Bazant, Electrochimica Acta 53, 7599 (2008)], we show that the spinodal and miscibility gaps generally shrink as the host particle size decreases to the nano-scale. Our work is motivated by recent experiments on the high-rate Li-ion battery material LiFePO4; this serves as the basis for our examples, but our analysis and conclusions apply to any intercalation material. We describe two general mechanisms for the suppression of phase separation in nano-particles: (i) a classical bulk effect, predicted by the Cahn-Hilliard equation, in which the diffuse phase boundary becomes confined by the particle geometry; and (ii) a novel surface effect, predicted by chemical-potential-dependent reaction kinetics, in which insertion/extraction reactions stabilize composition gradients near surfaces in equilibrium with the local environment. Composition-dependent surface energy and (especially) elastic strain can contribute to these effects but are not required to predict decreased spinodal and miscibility gaps at the nano-scale

Surface Kinetics and Generation of Different Terms in a Conservative Growth Equation

A method based on the kinetics of adatoms on a growing surface under epitaxial growth at low temperature in (1+1) dimensions is proposed to obtain a closed form of local growth equation. It can be generalized to any growth problem as long as diffusion of adatoms govern the surface morphology. The method can be easily extended to higher dimensions. The kinetic processes contributing to various terms in the growth equation (GE) are identified from the analysis of in-plane and downward hops. In particular, processes corresponding to the (h -> -h) symmetry breaking term and curvature dependent term are discussed. Consequence of these terms on the stable and unstable transition in (1+1) dimensions is analyzed. In (2+1) dimensions it is shown that an additional (h -> -h) symmetry breaking term is generated due to the in-plane curvature associated with the mound like structures. This term is independent of any diffusion barrier differences between in-plane and out of-plane migration. It is argued that terms generated in the presence of downward hops are the relevant terms in a GE. Growth equation in the closed form is obtained for various growth models introduced to capture most of the processes in experimental Molecular Beam Epitaxial growth. Effect of dissociation is also considered and is seen to have stabilizing effect on the growth. It is shown that for uphill current the GE approach fails to describe the growth since a given GE is not valid over the entire substrate.Comment: 14 pages, 7 figure

Suppression of Phase Separation in LiFePO4 Nanoparticles During Battery Discharge

Using a novel electrochemical phase-field model, we question the common belief that LixFePO4 nanoparticles separate into Li-rich and Li-poor phases during battery discharge. For small currents, spinodal decomposition or nucleation leads to moving phase boundaries. Above a critical current density (in the Tafel regime), the spinodal disappears, and particles fill homogeneously, which may explain the superior rate capability and long cycle life of nano-LiFePO4 cathodes.Comment: 27 pages, 8 figure