A relation between entropy and free energy change for metals

A linear thermodynamic relation between entropy at 298 K and free energy change between 0 and 298 K is discussed for metals with simple crystal structures, such as bcc, fcc and hcp. A plausible explanation of the linear function has been suggested in terms of the relationship between heat capacity and temperature. Some of the implications of the present findings have been discussed. A similar linear function is also demonstrated for the data estimated at the melting temperatures of the metals.     

Helical log-periodic array

A helical log-periodic array is designed considering the same parameters as those used in an existing log-periodic dipole array. The impedance and radiation characteristics are measured for both arrays. It is observed that the arrays have similar characteristics. Moreover, the advantage of the helical array is that its transverse dimension becomes much smaller.     

Radiation pattern of a vertical linear antenna over a conducting strip

The theoretical and experimental radiation patterns of an extended vertical line antenna placed over an infinite conducting strip are presented. The results show the nature of dependence of the level of back radiation upon the strip width and antenna height.     

Deep learning techniques for observing the impact of the global warming from satellite images of water-bodies

Multimedia Tools and Applications - Global warming is a threat to modern human civilization. There are different reasons for speed up the global average temperature. The consequences are...     

Numerical simulation of flow past row of square cylinders for various separation ratios

A systematic study for the flow around a row of five square cylinders placed in a side-by-side arrangement and normal to the oncoming flow at a Reynolds number of 150 is carried out through the numerical solution of the two-dimensional unsteady incompressible Navier-Stokes equations. Special attention is paid to investigate the effect of the spacing between the five cylinders on the wake structure and vortex shedding mechanism. The simulations are performed for the separation ratios (spacing to size ratio) of 1.2, 2, 3 and 4. Depending on the separation ratio the following flow patterns are observed: a flip-flopping pattern, in-phase and anti-phase synchronized pattern and non-synchronized pattern. These flow patterns are supposed to be a consequence of the interaction between two types of frequencies viz. the vortex shedding (primary) and the cylinder interaction (secondary) frequencies. At small separation ratio the flow is predominantly characterized by the jet in the gaps between successive cylinders and the secondary frequencies play a role in the resulting chaotic flow. On the contrary, at higher separation ratio the secondary frequencies almost disappear and the resulting flow becomes more synchronized dominated by the primary frequency.     

The Update Complexity of Selection and Related Problems

We present a framework for computing with input data specified by intervals, representing uncertainty in the values of the input parameters. To compute a solution, the algorithm can query the input parameters that yield more refined estimates in the form of sub-intervals and the objective is to minimize the number of queries. The previous approaches address the scenario where every query returns an exact value. Our framework is more general as it can deal with a wider variety of inputs and query responses and we establish interesting relationships between them that have not been investigated previously. Although some of the approaches of the previous restricted models can be adapted to the more general model, we require more sophisticated techniques for the analysis and we also obtain improved algorithms for the previous model. We address selection problems in the generalized model and show that there exist 2-update competitive algorithms that do not depend on the lengths or distribution of the sub-intervals and hold against the worst case adversary. We also obtain similar bounds on the competitive ratio for the MST problem in graphs.     

Hierarchical nanofabrication of microporous crystals with ordered mesoporosity

Shaped zeolite nanocrystals and larger zeolite particles with three-dimensionally ordered mesoporous (3DOm) features hold exciting technological implications for manufacturing thin, oriented molecular sieve films and realizing new selective, molecularly accessible and robust catalysts. A recognized means for controlled synthesis of such nanoparticulate and imprinted materials revolves around templating approaches, yet identification of an appropriately versatile template has remained elusive. Because of their highly interconnected pore space, ordered mesoporous carbon replicas serve as conceptually attractive materials for carrying out confined synthesis of zeolite crystals. Here, we demonstrate how a wide range of crystal morphologies can be realized through such confined growth within 3DOm carbon, synthesized by replication of colloidal crystals composed of size-tunable (about 10-40 nm) silica nanoparticles. Confined crystal growth within these templates leads to size-tunable, uniformly shaped silicalite-1 nanocrystals as well as 3DOm-imprinted single-crystal zeolite particles. In addition, novel crystal morphologies, consisting of faceted crystal outgrowths from primary crystalline particles have been discovered, providing new insight into constricted crystal growth mechanisms underlying confined synthesis.     

A robust model for domain recognition of acoustic communication using Bidirectional LSTM and deep neural network.

Neural Computing and Applications - This paper proposes a robust model for domain recognition of acoustic communication by using Bidirectional LSTM and deep neural network. The proposed model...