Ghoshal P.,Techno India |
Sen S.K.,University of Calcutta
2016 International Conference on Intelligent Control, Power and Instrumentation, ICICPI 2016 | Year: 2016
Various types of ADCs are available in the market with their relative strengths and constraints. Pipeline ADC is the latest inclusion in this list. It is very high speed and high resolution in nature. To make the conversion error free, a digital error correction technique has been used which is termed as 1.5 bits/stage. This design is a very useful technique to eliminate error due to comparator offset. The architecture is so designed that it does not need any extra circuitry for error detection and correction. To realize 4 bits from 4 stages, 1.5 bits/stage technique is used and error curves are drawn between theoretical and practical values which shows close proximity between them. © 2016 IEEE.
Roy S.,Techno India |
Ghosh B.,Metropolitan Institution Main |
Nayak N.,Birla Institute of Technology
Quantum Information and Computation | Year: 2010
We study the efficiency of two-qubit mixed entangled states as resources for quantum teleportation. We first consider two maximally entangled mixed states, viz., the Werner state, and a class of states introduced by Munro et al. . We show that the Werner state when used as teleportation channel, gives rise to better average teleportation fidelity compared to the latter class of states for any finite value of mixedness. We then introduce a non-maximally entangled mixed state obtained as a convex combination of a two-qubit entangled mixed state and a two-qubit separable mixed state. It is shown that such a teleportation channel can outperform another non-maximally entangled channel, viz., the Werner derivative for a certain range of mixedness. Further, there exists a range of parameter values where the former state satisfies a Bell-CHSH type inequality and still performs better as a teleportation channel compared to the Werner derivative even though the latter violates the inequality. © Rinton Press.
Sarkar S.,Techno India |
Ghosh N.,University of Calcutta |
Bhattacharya K.,University of Calcutta
Applied Optics | Year: 2012
A polarization phase shifting interferometer using a cyclic path configuration for measurement of phase nonuniformities in transparent samples is presented. A cube beam splitter masked by two linear polarizers is used to split the source wavefront into two counter propagating linearly polarized beams that pass through the sample. At the output of the interferometer, the two orthogonally polarized beams are rendered circularly polarized in the opposite sense through the use of a quarter wave plate. Finally, phase shifting is achieved by rotating a linear polarizer before the recording plane. In a rectangular path interferometer, although the two counter propagating wavefronts are laterally folded with respect to each other in the interferometer arms, the beams finally emerge mutually unfolded at the output of the interferometer. This phenomenon is utilized to create a reference if the sample is introduced in one lateral half of the beam in any one of the interferometer arms. The polarization phase shifting technique is used to generate four phase-shifted interferograms, which are utilized to evaluate the phase profile of the phase sample. Experimental results presented validate the proposed technique. © 2011 Optical Society of America.
Chowdhury S.,Techno India |
Sing J.K.,Jadavpur University |
Basu D.K.,Jadavpur University |
Nasipuri M.,Jadavpur University
Applied Soft Computing Journal | Year: 2011
This paper presents a novel scheme for feature extraction, namely, the generalized two-dimensional Fisher's linear discriminant (G-2DFLD) method and its use for face recognition using multi-class support vector machines as classifier. The G-2DFLD method is an extension of the 2DFLD method for feature extraction. Like 2DFLD method, G-2DFLD method is also based on the original 2D image matrix. However, unlike 2DFLD method, which maximizes class separability either from row or column direction, the G-2DFLD method maximizes class separability from both the row and column directions simultaneously. To realize this, two alternative Fisher's criteria have been defined corresponding to row and column-wise projection directions. Unlike 2DFLD method, the principal components extracted from an image matrix in G-2DFLD method are scalars; yielding much smaller image feature matrix. The proposed G-2DFLD method was evaluated on two popular face recognition databases, the AT&T (formerly ORL) and the UMIST face databases. The experimental results using different experimental strategies show that the new G-2DFLD scheme outperforms the PCA, 2DPCA, FLD and 2DFLD schemes, not only in terms of computation times, but also for the task of face recognition using multi-class support vector machines (SVM) as classifier. The proposed method also outperforms some of the neural networks and other SVM-based methods for face recognition reported in the literature. © 2010 Elsevier B.V. All rights reserved.
Sarker J.,Techno India |
Goswami S.K.,Jadavpur University
International Journal of Electrical Power and Energy Systems | Year: 2016
The increased use of nonlinear loads in distribution system is increasing the distortion in the voltage and current waveforms. Moreover, the distribution systems are inherently unbalanced. This paper presents Cuckoo Optimization Algorithm (COA) based Unified Power Quality Conditioner (UPQC) allocation in three phase unbalanced distribution network. The performance of UPQC is studied in terms of minimization of load disturbance during fault condition in the test systems, % reduction of total harmonic distortion and individual harmonics, minimization of real power loss, decrease in voltage unbalance and increase in cost savings during normal operating condition. The performance of COA is compared with other soft computing techniques to get the better results, i.e., better voltage profile, the optimal location and optimal number of UPQCs. © 2016 Elsevier Ltd. All rights reserved.
Mandal K.K.,Jadavpur University |
Mandal S.,Jadavpur University |
Bhattacharya B.,Techno India |
Chakraborty N.,Jadavpur University
Applied Soft Computing Journal | Year: 2015
This paper presents a novel parameter automation strategy for particle swarm optimization algorithm for solving non-convex emission constrained economic dispatch (NECED) problems. Many evolutionary techniques such as particle swarm optimization, differential evolution have been applied to solve these problems and found to perform in a better way in comparison with conventional optimization methods. But often these methods converge to a sub-optimal solution prematurely. This paper presents a new improved particle swarm optimization technique called self-organizing hierarchical particle swarm optimization technique with time-varying acceleration coefficients (SOHPSO-TVAC) for non-convex emission constrained economic dispatch (NECED) problems to avoid premature convergence. Generator ramp rate limits and prohibited operating zones are taken into account in problem formulation. Non-convex emission constrained economic dispatch (NECED) problem is obtained by considering both the economy and emission objectives. The performance of the proposed method is demonstrated on two sample test systems. The results of the proposed method are compared with other methods. It is found that the results obtained by the proposed method are superior in terms of fuel cost, emission output and losses. © 2014 Elsevier B.V. All rights reserved.
Sarker J.,Techno India |
Goswami S.K.,Jadavpur University
International Journal of Electrical Power and Energy Systems | Year: 2014
Optimal power flow is one of the key tasks to be performed in the complicated operation and planning of a power system. The Unified Power Flow Controller (UPFC) is a powerful power electronics device capable of providing complex control of power systems. In this paper, Gravitational Search Algorithm (GSA) is applied to solve optimal power flow problem in the presence of multiple UPFC devices. The performance of GSA is compared for accuracy and convergence characteristics with heuristic search techniques like Biogeography-Based Optimization (BBO), Stud Genetic Algorithm (StudGA), Genetic Algorithm (GA), Ant Colony Optimization (ACO), Probability-Based Incremental Learning (PBIL), on the different cases of standard test systems and real life power system. The tabulated results reveal that GSA has a great capability in handling power system planning and operational problems and to provide good quality solution quickly. The effort of optimal placement of multiple UPFC devices in power system cannot be commonly found in technical literature. © 2013 Elsevier Ltd. All rights reserved.
Lahiri S.,Dinabandhu Mahavidyalaya Bongaon |
Roychowdhury D.,Techno India |
Sekar Iyengar A.N.,Saha Institute of Nuclear Physics
Physics of Plasmas | Year: 2012
Long range temporal correlations in the fluctuations of the plasma floating potentials (measured using a Langmuir probe) are investigated in a dc glow discharge plasma. Keeping the neutral pressure constant, the discharge voltage was varied and at the formation of the plasma, quasi periodic oscillations were excited and on further increase of the discharge voltage they became chaotic (irregular) beyond a threshold voltage. We compared the Lyapunov exponent with the Hurst exponent obtained from R/S statistics which showed an opposite behaviour at the transition point. These results are perhaps new since we have not come across such comparative analysis for chaotic oscillations in a glow discharge plasma before. © 2012 American Institute of Physics.
Kumar A.,Indian Institute of Technology Jodhpur |
Adhikari S.,Indian Institute of Technology Jodhpur |
Banerjee S.,Indian Institute of Technology Jodhpur |
Roy S.,Techno India
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013
We propose a three-qubit partially entangled set of states as a shared resource for optimal and faithful quantum information processing. We show that our states always violate the Svetlichny inequality, which is a Bell-type inequality whose violation is a sufficient condition for the confirmation of genuine three-qubit nonlocality. Although our states can be physically realized from the generalized Greenberger-Horne-Zeilinger (GGHZ) states using a simple quantum circuit, the nonlocal properties of the set are quite different from the GGHZ states. Instead, they are similar to the maximal slice (MS) states, even though our states are not locally equivalent to the MS states. Unlike other two- and three-qubit partially entangled states, quantum teleportation using our states results in faithful transmission of information with unit probability and unit fidelity by performing only standard measurements for the sender, controller, and receiver. We further demonstrate that dense coding also leads to the deterministic transfer of a maximum number of bits from the sender to the receiver. We also introduce witness operators able to experimentally detect the family of states introduced. This work highlights the importance of both the local as well as nonlocal aspects of quantum correlations in multiqubit systems. © 2013 American Physical Society.
Chakrabarty S.,Techno India |
De D.,Maulana Abul Kalam Azad University of Technology
2012 International Conference on Radar, Communication and Computing, ICRCC 2012 | Year: 2012
Pattern recognition in rhythm of Tabla instrument in ICM (Indian Classical Music) is very complex task that is the combination of speech, audio, and their signal processing techniques. In this paper we proposed a system that identify the basic source rhythm and then modify the rhythm to improve the quality of source rhythm by using Genetic Algorithm. In simple terms, rhythm is a word that refers to the length of each note in a piece of music, the combination of beats. In order to develop high quality of rhythm in an efficient manner, it is essential to identify the correct sequence of the different PRAKAR of Tabla rhythm like, THEKA, UTHAN, TUKADA, RELA, LAGGI, KAIDA, TIHAI, CHAKRADAR, etc. PRAKAR means different sorts of rhythmic compositions used in Tabla. The focus of this study is to explore the efficiency of Genetic Algorithm to search for an optimum combination of rhythm to improve the Music Quality Metric. © 2012 IEEE.