Daxini S.D.,Babaria Institute of Technology |
Prajapati J.M.,Gujarat University
The Scientific World Journal | Year: 2014
Meshfree methods are viewed as next generation computational techniques. With evident limitations of conventional grid based methods, like FEM, in dealing with problems of fracture mechanics, large deformation, and simulation of manufacturing processes, meshfree methods have gained much attention by researchers. A number of meshfree methods have been proposed till now for analyzing complex problems in various fields of engineering. Present work attempts to review recent developments and some earlier applications of well-known meshfree methods like EFG and MLPG to various types of structure mechanics and fracture mechanics applications like bending, buckling, free vibration analysis, sensitivity analysis and topology optimization, single and mixed mode crack problems, fatigue crack growth, and dynamic crack analysis and some typical applications like vibration of cracked structures, thermoelastic crack problems, and failure transition in impact problems. Due to complex nature of meshfree shape functions and evaluation of integrals in domain, meshless methods are computationally expensive as compared to conventional mesh based methods. Some improved versions of original meshfree methods and other techniques suggested by researchers to improve computational efficiency of meshfree methods are also reviewed here. © 2014 S. D. Daxini and J. M. Prajapati.
Shah S.,k-Technology |
Singh M.,Babaria Institute of Technology
Proceedings - International Conference on Communication Systems and Network Technologies, CSNT 2012 | Year: 2012
Clustering analysis is a descriptive task that seeks to identify homogeneous groups of objects based on the values of their attributes. This paper proposes a new algorithm for Modified K-Means clustering which executes like the K-means algorithm and k-medoids algorithms and tests several methods for selecting initial cluster. Modified K-Mean Algorithm is better in terms of number of clusters and execution time comparisons with K-Mean and K-Mediod. Proposed algorithm is evaluated using real data and results are compared with k-Means and k-medoids where it takes reduced time in computation and better performance compared to K-Means and K-Medoids algorithms. © 2012 IEEE.
Pathak H.,Babaria Institute of Technology
Proceedings - 2011 International Conference on Communication Systems and Network Technologies, CSNT 2011 | Year: 2011
With the progress in wireless communications techniques in recent years, a new promising concept of wireless sensor networks has received a well deserved attention by researchers all over the world. Embedded sensors offer intelligent devices and systems that are able to react to events and physical conditions of the real world. The most important component in sensor is its TX/RX antenna. In this paper, UWB printed monopole antenna with embedded reconfigurable multi band frequency rejection notches is proposed. Frequency notch is achieved by using a ground-plane slot (GPS) and lumped capacitors. Reconfigurability is introduced in a way you can independently switch ON/OFF the band notches by mean of RF switches. Simulation results are verified with measurements. © 2011 IEEE.
Patel A.J.,Babaria Institute of Technology |
Patel J.S.,Rishabh Software
2013 International Conference on Intelligent Systems and Signal Processing, ISSP 2013 | Year: 2013
Classification of the unknown dataset can be obtained by several methods. Ensemble classifier methods are proved to be the better for classification. Learn++, An incremental learning algorithm, which allows supervised classification algorithms to learn from new data without forgetting previously acquired knowledge even when the previously used data is no longer available. Learn++ suffers from inherent 'out-voting problem when asked to learn new classes, which causes it to generate an unnecessarily large number of classifiers. Also, in Learn++, distribution update rule based on performance of compound hypothesis, for selecting training set of the next weak classifier, it allows an efficient incremental learning capability when new classes are introduced. Whereas, in AdaBoost distribution update rule based on individual hypothesis guarantees robustness and prevents performance deterioration. In proposed algorithm, it combines the advantages of both the methods. It provides weight updating rule based on a combination of individual hypothesis and compound hypothesis which provide optimum performance level. © 2013 IEEE.
Deshpande M.P.,Sardar Patel University |
Sakariya P.N.,Sardar Patel University |
Sakariya P.N.,Babaria Institute of Technology |
Bhatt S.V.,Sardar Patel University |
And 3 more authors.
Materials Science in Semiconductor Processing | Year: 2014
Bi2S3 is a direct band gap semiconductor with a band gap of 1.3 eV. It belongs to the family of metal chalcogenides of type A 2VB3VI (A=As, Sb, and Bi; B=S, Se, and Te), whose importance in photovoltaic and thermoelectric applications is well recognized. Although nanostructures of Bi2S3 have been obtained using a number of techniques, reports on assemblies of Bi 2S3 are sparse. In the present work, we prepared single crystalline bismuth sulfide (Bi2S3) nanorods at room temperature by reacting Bi(NO3)3, thioacetamide (TAA), hydrochloric acid and distilled water. Energy dispersive analysis of X-rays (EDAX) obtained from Bi2S3 nanorods indicated no incorporation of other foreign impurities in it. X-ray diffraction confirmed the single phase of Bi2S3 and different diffracting planes were indexed based on the orthorhombic structure and lattice parameters were determined. X-ray photoelectron spectroscopy (XPS) was used to evaluate its composition and purity. The synthesized nanorods with different images observed under transmission electron microscopy (TEM) are shown in the paper and the selected area electron diffraction (SAED) pattern obtained from these nanorods shows their single crystalline behavior. Raman measurement performed at room temperature using Ar+ laser (488 nm) confirms the presence of 238 cm-1 and 972 cm-1 phonon modes. The optical absorption spectra obtained by UV-vis spectrometer show blue shift in comparison to bulk Bi2S3 while its thermal stability was studied by thermogravimetric analysis. © 2013 Elsevier Ltd.