National Institute of Technology, Karnataka

About: National Institute of Technology, Karnataka is a education organization based out in Mangalore, Karnataka, India. It is known for research contribution in the topics: Computer science & Corrosion. The organization has 5017 authors who have published 7057 publications receiving 70367 citations.

Particle deposition in human respiratory system: deposition of concentrated hygroscopic aerosols.

Abstract: In the nearly saturated human respiratory tract, the presence of water-soluble substances in the inhaled aerosols can cause change in the size distribution of the particles. This consequently alters the lung deposition profiles of the inhaled airborne particles. Similarly, the presence of high concentration of hygroscopic aerosols also affects the water vapor and temperature profiles in the respiratory tract. A model is presented to analyze these effects in human respiratory system. The model solves simultaneously the heat and mass transfer equations to determine the size evolution of respirable particles and gas-phase properties within human respiratory tract. First, the model predictions for nonhygroscopic aerosols are compared with experimental results. The model results are compared with experimental results of sodium chloride particles. The model reproduces the major features of the experimental data. The water vapor profile is significantly modified only when a high concentration of particles is present. The model is used to study the effect of equilibrium assumptions on particle deposition. Simulations show that an infinite dilution solution assumption to calculate the saturation equilibrium over droplet could induce errors in estimating particle growth. This error is significant in the case of particles of size greater than 1 mum and at number concentrations higher than 10(5)/cm(3).

Choice of a classifier, based on properties of a dataset: case study-speech emotion recognition

Abstract: In this paper, the process of selecting a classifier based on the properties of dataset is designed since it is very difficult to experiment the data on n—number of classifiers As a case study speech emotion recognition is considered Different combinations of spectral and prosodic features relevant to emotions are explored The best subset of the chosen set of features is recommended for each of the classifiers based on the properties of chosen dataset Various statistical tests have been used to estimate the properties of dataset The nature of dataset gives an idea to select the relevant classifier To make it more precise, three other clustering and classification techniques such as K-means clustering, vector quantization and artificial neural networks are used for experimentation and results are compared with the selected classifier Prosodic features like pitch, intensity, jitter, shimmer, spectral features such as mel frequency cepstral coefficients (MFCCs) and formants are considered in this work Statistical parameters of prosody such as minimum, maximum, mean ( $$\mu$$ ) and standard deviation ( $$\sigma$$ ) are extracted from speech and combined with basic spectral (MFCCs) features to get better performance Five basic emotions namely anger, fear, happiness, neutral and sadness are considered For analysing the performance of different datasets on different classifiers, content and speaker independent emotional data is used, collected from Telugu movies Mean opinion score of fifty users is collected to label the emotional data To make it more accurate, one of the benchmark IIT-Kharagpur emotional database is used to generalize the conclusions

Fabrication and high-temperature structural characterization study of porous anodic alumina membranes

Abstract: Porous anodic alumina (PAA) membranes with highly ordered array of nanopores were prepared by two-step anodization process. Studies on structural and thermal properties and the thermal stability of the prepared PAA membranes were carried out. Investigation using scanning electron microscopy, atomic force microscopy, X-ray diffraction, thermal analysis and infrared spectroscopy was performed on the prepared PAA membranes at room temperature and in the temperature range 600–1,400 °C. The as-prepared PAA membranes revealed the amorphous nature. Polycrystalline PAA membranes were obtained by annealing carried out at different temperatures. Annealing study confirmed that the heat treatment transformed the amorphous PAA membranes to their crystalline phases, namely, γ-alumina at about 870 °C and then to α-alumina around 1,250 °C.