Central University of Kerala

About: Central University of Kerala is a education organization based out in Kāsaragod, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 556 authors who have published 881 publications receiving 7474 citations.

Tunable surface plasmon polaritons in metal-strip waveguides with magnetized semiconductor substrates in Voigt configuration

Abstract: The properties of surface plasmon polaritons (SPPs) in a magnetically tunable strip waveguide geometry comprising of a metal film of finite width deposited on a magnetized semiconductor and covered by an isotropic dielectric material were studied in Voigt configuration. The method of lines was used to compute the dispersion relation of fundamental modes, and the dependence of the propagation constant on metal film dimensions, material parameters and biasing magnetic field was considered. The bounded SPPs are nonreciprocal with respect to the direction of the biasing magnetic field, producing a nonreciprocal phase shift of the order of 2–18 rad mm−1 at a wavelength of excitation 1.55 μm. Moreover, controlled propagation of SPP modes and their effective tuning are possible in this strip geometry, which enables the design and development of tunable optoelectronic devices.

Semiconductor Quantum Dots and Core Shell Systems for High Contrast Cellular/Bio Imaging

Abstract: QDs are excellent materials for bioimaging because of its unique properties like high level of biocompatibility and its absorption and emission can be tuned with particle size. QDs are an extremely photostable and are considered to be brighter probes as compared to the traditional organic based dye. If the QDs are toxic in nature, it is necessary to surface modify ie, to add or cover some material like a shell over such types of QDs to reduce the toxicity. The non/least-toxic organic based dyes also can be used for cellular imaging application, so that it will cover the toxic QDs to protect the cellular surface and provide good images. Their attractive optical properties promise sensitive cancer imaging properties. In inorganic nanostructures, the ZnS QD is one of the less toxic material and several works are carried using ZnS capped with CdSe QDs for reducing the toxicity. This chapter deals with the cellular/bioimaging applications of the semiconductor QDs.

Script based trilingual handwritten word level multiple skew estimation

Abstract: Skew estimation and correction plays an important role in document analysis. In the present work, we proposed a model to estimate multiple skews present in trilingual such as Devanagari, English, and Kannada handwritten documents at word level with a priori knowledge about the corresponding scripts. The idea of using different skew estimation techniques for different scripts such as Hough transform (HT) for Devanagari words, Gaussian Mixture Models (GMM) and convex hull for Kannada and English words is proposed. The effectiveness of these approaches has been reported by testing on a dataset consisting of 1000 words in each script. Experimental results show that the proposed approaches are effective in estimating and correcting the handwritten skew words.

Performance evaluation of fractal features toward seizure detection from electroencephalogram signals

Abstract: Electroencephalogram signals are the classical gold standard for the diagnosis of seizures. Important information that enables the effective detection of seizure is hidden due to the complex and chaotic nature of electroencephalogram signals. The capability of fractal dimension to extract complex information from signals or images is well utilized in various domains. In this chapter, the ability of three well-known fractal dimension feature extraction methods (e.g., Katz fractal dimension, Higuchi fractal dimension, and Petrosian fractal dimension) to classify epileptic and nonepileptic electroencephalogram signals is evaluated. The features are fed to support vector machine classifier for the classification of epileptic and nonepileptic electroencephalogram signals. The results of support vector machine classifier show that the fractal features are good measures to characterize the complex information of epileptic signals.

Longitudinal Localized Surface Plasmons in Trimer Nanocylinder System

Abstract: We report the near field localized surface plasmon characteristics of triangular system of silver nanocylinders and shell nanocylinders interacting with incident plane wave, studied using finite element method. The trimer nanocylinder system possesses far greater structural tunability than either a single nanorod or a nanoshell, along with much larger local field intensity enhancements and far greater sensitivity. The effect of geometrical as well as material parameters on the longitudinal localized plasmon resonance of the trimer nanosystem was investigated. The results provide insight in to the possible tunability of the localized plasmon modes which could find application in designing of chemical and biological sensors, electron emitters, etc.