Paul D.,SSBB and Senior Member ASQ |
Mandal S.N.,Kalyani Government Engg College |
Mukherjee D.,B.E.S.U. |
Bhadra Chaudhuri S.R.,B.E.S.U.
Renewable Energy | Year: 2010
System efficiency and payback time are yet to attain a commercially viable level for solar photovoltaic energy projects. Despite huge development in prediction of solar radiation data, there is a gap in extraction of pertinent information from such data. Hence the available data cannot be effectively utilized for engineering application. This is acting as a barrier for the emerging technology. For making accurate engineering and financial calculations regarding any solar energy project, it is crucial to identify and optimize the most significant statistic(s) representing insolation availability by the Photovoltaic setup at the installation site. Quality Function Deployment (QFD) technique has been applied for identifying the statistic(s), which are of high significance from a project designer's point of view. A MATLAB™ program has been used to build the annual frequency distribution of hourly insolation over any module plane at a given location. Descriptive statistical analysis of such distributions is done through MINITABTM. For Building Integrated Photo Voltaic (BIPV) installation, similar statistical analysis has been carried out for the composite frequency distribution, which is formed by weighted summation of insolation distributions for different module planes used in the installation. Vital most influential statistic(s) of the composite distribution have been optimized through Artificial Neural Network computation. This approach is expected to open up a new horizon in BIPV system design. © 2010 Elsevier Ltd.
Sinha S.K.,Indian Institute of Technology Kharagpur |
Bhattacharya R.,BESU |
Ray S.K.,Indian Institute of Technology Kharagpur |
Manna I.,Indian Institute of Technology Kharagpur |
Manna I.,Indian Central Glass and Ceramic Research Institute
Materials Letters | Year: 2011
Nanostructured tin oxide thin films were deposited on the Si (100) substrate using the pulsed laser deposition technique at different substrate temperatures (300, 450 and 600 °C) in an oxygen atmosphere. The structure and morphology of the as-deposited films indicate that the film crystallinity and surface topography are influenced by the deposition temperature by changing from an almost amorphous to crystalline microstructure and smoother topography at a higher substrate temperature. The photoluminescence measurement of the SnO2 films shows three stable emission peaks centered at respective wavelengths of 591, 554 and 560 nm with increasing deposition temperature, contributed by the oxygen vacancies. © 2010 Published by Elsevier B.V.
Pati S.P.,UGC-DAE Consortium for Scientific Research |
Bhushan B.,UGC-DAE Consortium for Scientific Research |
Basumallick A.,BESU |
Kumar S.,Jadavpur University |
Das D.,UGC-DAE Consortium for Scientific Research
Materials Science and Engineering B: Solid-State Materials for Advanced Technology | Year: 2011
Nanocomposites of Fe-NiO are synthesized by the mechanical milling technique. The phase purity of the sample was checked by X-ray diffraction (XRD), which shows only lines of α-Fe and NiO. Transmission electron microscopy (TEM) measurements confirmed a homogeneous dispersion of α-Fe nanoparticles in NiO matrix. Magnetic hysteresis measurements showed an enhancement in coercivity at room temperature with increasing milling durations and presence of exchange bias field. With increasing milling durations, the exchange field is found to increase while blocking temperature decreased. Presence of defects in Fe-NiO nanocomposites ball-milled for prolonged durations is confirmed by positron annihilation lifetime spectroscopy (PALS) measurements. Mössbauer spectroscopic measurements reveal that Fe nanoparticles are in the blocked state though their size is less than the critical size for becoming single domain and superparamagnetic. This is attributed to strong exchange coupling between the ferromagnetic and antiferromagnetic moments. © 2011 Elsevier B.V. All rights reserved.
Barman N.S.,Jadavpur University |
Ghosh S.,BESU |
De S.,Jadavpur University
Bioresource Technology | Year: 2012
This study presents a model for fixed bed downdraft biomass gasifiers considering tar also as one of the gasification products. A representative tar composition along with its mole fractions, as available in the literature was used as an input parameter within the model. The study used an equilibrium approach for the applicable gasification reactions and also considered possible deviations from equilibrium to further upgrade the equilibrium model to validate a range of reported experimental results. Heat balance was applied to predict the gasification temperature and the predicted values were compared with reported results in literature. A comparative study was made with some reference models available in the literature and also with experimental results reported in the literature. Finally a predicted variation of performance of the gasifier by this validated model for different air-fuel ratio and moisture content was also discussed. © 2011 Elsevier Ltd.
Das A.,NH School |
Nonlinear Analysis: Real World Applications | Year: 2010
In this paper, we shall attempt fractal analysis of time series derived from two popular song types. Each type of song has its own notation, which is to be followed by an artist singing it. We found earlier that the fractal dimension (D) calculated from a song is a good measure of the complexity of its notation. The purpose of the present study is to find whether, if the same song is sung by different performers, D will vary, and how an individual's performance varies when singing songs with the same notation and same wording. We shall employ nonlinear time series methods to calculate D for different samples of the said two types to address this question. © 2009 Elsevier Ltd. All rights reserved.
Ghosh C.K.,Dr. B. C. Roy Engineering College |
Progress In Electromagnetics Research C | Year: 2013
Design of (2 × 2) E-shaped microstrip patch antenna array integrated with spiral ring resonators (SRRs) is introduced for the reduction of cross-polar (XP) radiation. The addition of SRRs in the array structure does not affect other characteristics of the array antenna. The array is designed to function in the 5.25 GHz which corresponds to IEEE 802.11a wireless LAN application. The characteristic analysis such as return loss (RL), bandwidth (BW), and radiation patterns of the antenna with and without SRRs have been investigated. The array offers a bandwidth of 405 MHz (For RL < -10 dB) covering frequencies ranges from 5.175 to 5.580 GHz and gain of 12.60 dBi has been achieved. The array has been studied both numerically and experimentally by introducing SRRs. The XP radiation has been reduced by 10.5 dB with two sets of SSRs of similar geometry placed in between the patch elements of the array structure. Prototype antennas with and without SRRs have been fabricated tested and a remarkable agreement is obtained between the measured and the simulated results.
Si T.,National Institute of Technology Durgapur |
Jana N.D.,National Institute of Technology Durgapur |
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011
Constrained function optimization using particle swarm optimization (PSO) with polynomial mutation is proposed in this work. In this method non-stationary penalty function approach is adopted and polynomial mutation is performed on global best solution in PSO. The proposed method is applied on 6 benchmark problems and obtained results are compared with the results obtained from basic PSO. The experimental results show the efficiency and effectiveness of the method. © 2011 Springer-Verlag.
Jana N.D.,National Institute of Technology Durgapur |
Advances in Intelligent Systems and Computing | Year: 2014
In this paper, particle swarm optimization (PSO) with levy flight is proposed. PSO is a population based global optimization algorithm has faster convergence but often gets stuck in local optima due to lack of diversity in the population. In the proposed method, levy flight is applied on a percentage of particles excluding global best particle to create diversity in population. Adaptive polynomial mutation is applied on global best (gbest) particle to get it out from the trap in local optima. The method is applied on well-known benchmark unconstrained functions and results are compares with classical PSO. Form the experimental result, it has been observed that the proposed method performs better than classical PSO. © Springer International Publishing Switzerland 2014.
Homeopathy | Year: 2013
Background: Avogadro's Number gives 12c as the limit beyond which no original substance can be present in a highly diluted and succcussed (potentised) homeopathic medicine, implying that chemically such dilutions consist of nothing but the vehicle. But there is evidence that living systems react to homeopathic medicines diluted even above 12c. To explain how such medicines differ from another I hypothesise that altered structure may cause the difference, such as that between diamond and amorphous carbon. Some scientists have argued that dilution followed by succussion may lead to altered structural arrangement of water molecules. This concept may be termed 'Induced Molecular Structure'. Methods: Dielectric dispersion studies were conducted in a broad range with potencies below and above the Avogadro limit by taking 6c and 30c potencies of Graphites and Cuprum Metallicum in liquid form. Measurements were made with an Anomalous Dielectric Dispersion Detector (A3D), an instrument developed by the author. Results: Experiments were carried out in a frequency range of 100kHz to 50MHz. Shifting of resonance frequencies as a function of medicine and potency, with potencies below and above the Avogadro limit, was observed. Conclusion: The range of resonance frequencies suggest that the phenomenon might originate from oscillation of dipoles caused by electric field in variously structured and polarised water. Also, there is reasonable evidence that frequencies change with materials and potency. © 2013 The Faculty of Homeopathy.
10th International Conference on Geosynthetics, ICG 2014 | Year: 2014
An experimental study was conducted to examine the modified properties of bitumen after mixing non-biodegradable solid wastes namely waste plastic bag, plastic cup, milk pouch and crumb rubber obtained from municipal solid wastes. In this investigation different proportion of such wastes were mixed with the bitumen for evaluating the changed characteristics of the mixed sample and compared with the properties of the virgin bitumen. Results of experiments indicated that addition of 1.0% plastic bag and 1.0% crumb rubber with the bitumen may be considered as the better thermal susceptible binder and can be used effectively for construction of flexible pavement without altering the grade of bitumen.