PRATIT: a CNN-based emotion recognition system using histogram equalization and data augmentation

Multimedia Tools and Applications - Emotions are spontaneous feelings that are accompanied by fluctuations in facial muscles, which leads to facial expressions. Categorization of these facial...     

An artificial neural network approach on parametric optimization of laser micro-machining of die-steel

In the present research, laser micro machining (LMM) of tungsten-molybdenum general purpose high speed steel (Rex M2) has been studied. Selection of optimum machining parameter combinations for obtaining higher depth of groove and smaller height of recast layer is a challenging task in LMM due to the presence of a large number of process variables. There is no perfect combination of parameters which can simultaneously result in both the highest depth of groove and lowest height of recast layer. This paper presents an attempt to develop a strategy for predicting the optimum machining parameter setting for the generation of the maximum depth of groove with minimum height of recast layer. A feed forward back-propagation neural network has been developed to model the machining process. The model, after proper training, is capable of predicting the response parameters as a function of four different control parameters. Experimental results demonstrate that the machining model is suitable and the optimization strategy satisfies practical requirements. The developed model has been found to be quite unique, powerful and flexible.     

Investigation of rectangular solid-core photonic crystal fiber as temperature sensor

Microsystem Technologies - In this article, a rectangular solid-core photonic crystal fiber (PCF) is proposed as temperature sensor. The air-holes of the PCF have been filled with Ethyl alcohol...     

On the polynomial solvability of distributionally robust k-sum optimization

In this paper, we define a distributionally robust k-sum optimization problem as the problem of finding a solution that minimizes the worst-case expected sum of up to the k largest costs of the elements in the solution. The costs are random with a joint probability distribution that is not completely specified but rather assumed to be known to lie in a set of probability distributions. For k=1, this reduces to a distributionally robust bottleneck optimization problem while for k=n, this reduces to distributionally robust minimum sum optimization problem. Our main result is that for a Fréchet class of discrete marginal distributions with finite support, the distributionally robust k-sum combinatorial optimization problem is solvable in polynomial time if the deterministic minimum sum problem is solvable in polynomial time. This extends the result of Punnen and Aneja [On k-sum optimization, Oper. Res. Lett. 18(5)(1996), pp. 233–236] from the deterministic to the robust case. We show that this choice of the set of distributions helps preserve the submodularity of the k-sum objective function which is an useful structural property for optimization problems.     

A novel strategy for fabricating zirconia implants with a trabecular biomimetic porous surface

For successful osseointegration of load-bearing implants, an improved bone–implant contact area through a trabecular porous surface resulting in minimized stress shielding effect is highly desirable. We propose a novel strategy of green net shaping a ceramic dough, combined with a reticular foam replica method and gradient coating, to fabricate biomimetic porosity in a customizable ceramic dental implant for the first time. About 85 vol% porosity and 300–600-μm pore size were evident in microCT and electron microscopy of the sintered samples, suitable for bone ingrowth. Excellent integrity at the interface along with homogeneous distribution of secondary alumina phase in zirconia matrix was achieved, despite the difference in the green state powder loading between the dough and the slurry.     

Green Machining to Net Shape Alumina Ceramics Prepared Using Different Processing Routes

In the present study, the net shape manufacturing of alumina ceramics was carried out using computer numerically controlled (CNC) machining of differently processed alumina green bodies using different tool materials and geometries. In case of a carbide-coated tool, severe wear was observed; on the contrary, a diamond-coated tool was used successfully. The profile of the as-machined surface was found to be smooth using diamond-coated flat tool. Near net shape alumina was demonstrated using CNC green machining from optimized machining conditions. Optical micrograph and the surface roughness of the as-machined samples showed good surface finish for the green bodies with higher binder content.     

Natural dyeing with anthocyanins from Hibiscus rosa sinensis flowers

A new approach for natural dyeing with anthocyanin has been discussed along with a convenient method of extraction. Anthocyanin from Hibiscus flowers has been extracted by developing a method using methanolic solution of 4% citric acid. The new method gave better yield of anthocyanin as compared with methanolic solution of 0.1% hydrochloric acid. It has been also shown that pH of the extract plays an important role on the dye, thus by adjusting the pH of the extract at 4, dyeing of cotton and silk together with metal mordanting gave different colors. The best dyeing results were obtained for stannous mordanted fabrics in terms of fastness properties. The role of metal ion complexation of stannous salt with the dye extract has been confirmed through UV‐Vis and FTIR spectra. Antioxidant activity of the anthocyanin extract seemed to have contributed to enhance the fastness properties of the dyed fabrics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis of Nanocrystalline Alumina Using Egg White

A new simplified route to prepare nanocrystalline alumina powders is proposed. The method involved the use of freshly extracted egg white (ovalbumin) and aluminum nitrate in an aqueous medium. Changes in ionic strength upon addition of aluminum nitrate resulted in gelation of ovalbumin. The added metal ions were dispersed in the gelled ovalbumin matrix. Heat treatment of the gelled mass resulted in nanosized γ alumina at as low a temperature as 330°C. TEM analysis showed that the particle size ranged from 15 to 80 nm.