Search

Your search keyword '"Mathew, Steve"' showing total 10 results
Start Over Author "Mathew, Steve"
10 results on '"Mathew, Steve"'

1. A study on the deviations in performance of FNNs and CNNs in the realm of grayscale adversarial images

Author

Nagabushanam, Durga Shree, Mathew, Steve, and Chowdhary, Chiranji Lal

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning
Abstract

Neural Networks are prone to having lesser accuracy in the classification of images with noise perturbation. Convolutional Neural Networks, CNNs are known for their unparalleled accuracy in the classification of benign images. But our study shows that they are extremely vulnerable to noise addition while Feed-forward Neural Networks, FNNs show very less correspondence with noise perturbation, maintaining their accuracy almost undisturbed. FNNs are observed to be better at classifying noise-intensive, single-channeled images that are just sheer noise to human vision. In our study, we have used the hand-written digits dataset, MNIST with the following architectures: FNNs with 1 and 2 hidden layers and CNNs with 3, 4, 6 and 8 convolutions and analyzed their accuracies. FNNs stand out to show that irrespective of the intensity of noise, they have a classification accuracy of more than 85%. In our analysis of CNNs with this data, the deceleration of classification accuracy of CNN with 8 convolutions was half of that of the rest of the CNNs. Correlation analysis and mathematical modelling of the accuracy trends act as roadmaps to these conclusions., Comment: 19 pages, 12 tables, 4 figures

Published
2022

2. Tonal Frequencies, Consonance, Dissonance: A Math-Bio Intersection

Author

Mathew, Steve

Subjects
Computer Science - Sound, Electrical Engineering and Systems Science - Audio and Speech Processing
Abstract

To date, calculating the frequencies of musical notes requires one to know the frequency of some reference note. In this study, first-order ordinary differential equations are used to arrive at a mathematical model to determine tonal frequencies using their respective note indices. In the next part of the study, an analysis that is based on the fundamental musical frequencies is conducted to theoretically and neurobiologically explain the consonance and dissonance caused by the different musical notes in the chromatic scale which is based on the fact that systematic patterns of sound invoke pleasure. The reason behind the richness of harmony and the sonic interference and degree of consonance in musical chords are discussed. Since a human mind analyses everything relatively, anything other than the most consonant notes sounds dissonant. In conclusion, the study explains clearly why musical notes and in toto, music sounds the way it does., Comment: 9 pages, 1 figure, 1 table

Published
2021

3. Effect of Aligning Forces by Two Preadjusted Edgewise Techniques on a Buccally Positioned Maxillary Canine at Varying Vertical Displacements: A Finite Element Study.

Author

Mathew, Steve, Batra, Puneet, Arora, Nitin, Singh, Ashish Kumar, Kannan, Sridhar, and Talwar, Aditya

Subjects
OCCLUSAL adjustment, CORRECTIVE orthodontics, DENTAL materials, CUSPIDS, FINITE element method
Abstract

Objective: To evaluate the effect of continuous arch and piggyback mechanics in a straight wire appliance (SWA) for the alignment of buccal and variably vertically positioned maxillary canines. Methods: A three-dimensional finite element model with near-normal occlusion and buccal and vertically displaced maxillary canines was used. Two groups were created to simulate two commonly used SWAs techniques, continuous archwire (Group 1) and piggyback models (Group 2). Each group had three subgroups with varying vertical displacement of the canine from 2 to 6 mm from the occlusal plane. The displacement and stress distribution were noted in each group. Results: As the vertical displacement increased in Group 1, the concentration of von Mises stress increased progressively at the incisal third (0.36, 0.41 and 0.44 MPa) at 2, 4, and 6 mm, respectively, with decreased maximum occlusal movement in the vertical plane with respect to the canine. Group 2 exhibited a similar pattern but greater occlusal movement of the canine compared with Group 1. Conclusion: A vertical displacement of 4 mm is the optimal level at which continuous arch mechanics should be considered. For displacements beyond 4 mm, the piggyback wire technique is a suitable alternative. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

9. Design of a parallel application of image segmentation based on Corba : feasibility study

Author

Jiménez Montero, Jorge, Mathew, Steve, Expósito Singh, David, and Universidad Carlos III de Madrid. Departamento de Informática

Subjects
Proceso en paralelo, Informática, Segmentación de imágenes, Visión artificial, Proceso de imágenes
Abstract

In computer vision, segmentation refers to the process of partitioning a digital image into multiple segments. This process involves a high consumption of resources, both memory and CPU. Therefore, these applications are specially suited for HPC (High-performance computing) environments. Nowadays, a wide variety of methods and algorithms have been available recently to deal with the trouble of the segmentation of images, one of them is used in this project that was called PSRG. This algorithm was designed to be executed parallel. Parallel executions use MPI for performing the data distribution. We have considered interesting to enable these simulations on machines with different architectures and distributed over wide area networks, allowing them to run on heterogeneous architectures and/or operative systems. To achieve it, we started this project with an implementation of a CORBA−based communications library. Once the development finished, we proceed to evaluate the performance of this new version of PSRG. Ingeniería en Informática

Published
2011

10. The crosslinking of polysaccharides with polyamines and dextran-polyallylamine antibacterial hydrogels.

Author

O'Connor NA, Abugharbieh A, Yasmeen F, Buabeng E, Mathew S, Samaroo D, and Cheng HP

Subjects
Absorption, Physicochemical, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents chemistry, Dextrans chemical synthesis, Dextrans chemistry, Escherichia coli drug effects, Hydrogels chemical synthesis, Hydrogels chemistry, Microbial Sensitivity Tests, Polyamines chemical synthesis, Polyamines chemistry, Spectroscopy, Fourier Transform Infrared, Staphylococcus aureus drug effects, Anti-Bacterial Agents pharmacology, Cross-Linking Reagents pharmacology, Dextrans pharmacology, Hydrogels pharmacology, Polyamines pharmacology
Abstract

A facile modular approach to rapidly prepare pH-responsive hydrogels by crosslinking polysaccharides with polyamines is demonstrated. Hydrogels are prepared by first reacting the less reactive polysaccharides with the cross-linker epichlorohydrin and completed by the addition of polyamines. The crosslinking of polysaccharides with polyamines provides a facile method for incorporating functionality into polysaccharide based hydrogels. This process is demonstrated with the polysaccharides dextran, pullulan and carboxymethyl cellulose and with the polyamines polyallylamine and polyethylene imine. The hydrogels were characterized by FTIR and swelling studies, which showed pH-dependent swelling due to the presence of the polyamine. The hydrogels can also be tailored by varying the mass ratio between the polysaccharide and polyamine. Absorption studies of organic analytes showed the polyamine content affecting the uptake of a charged substrate (methylene blue) and no effect on a neutral substrate (6-methyl coumarin). This synthetic method was also used to prepare hydrogels with antibacterial activity against E. coli and S. aureus by utilizing an amphiphilic polyallylamine., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Published
2015
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results