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Showing papers by "Jadavpur University published in 2009"


Journal ArticleDOI
TL;DR: A family of improved variants of the DE/target-to-best/1/bin scheme, which utilizes the concept of the neighborhood of each population member, and is shown to be statistically significantly better than or at least comparable to several existing DE variants as well as a few other significant evolutionary computing techniques over a test suite of 24 benchmark functions.
Abstract: Differential evolution (DE) is well known as a simple and efficient scheme for global optimization over continuous spaces. It has reportedly outperformed a few evolutionary algorithms (EAs) and other search heuristics like the particle swarm optimization (PSO) when tested over both benchmark and real-world problems. DE, however, is not completely free from the problems of slow and/or premature convergence. This paper describes a family of improved variants of the DE/target-to-best/1/bin scheme, which utilizes the concept of the neighborhood of each population member. The idea of small neighborhoods, defined over the index-graph of parameter vectors, draws inspiration from the community of the PSO algorithms. The proposed schemes balance the exploration and exploitation abilities of DE without imposing serious additional burdens in terms of function evaluations. They are shown to be statistically significantly better than or at least comparable to several existing DE variants as well as a few other significant evolutionary computing techniques over a test suite of 24 benchmark functions. The paper also investigates the applications of the new DE variants to two real-life problems concerning parameter estimation for frequency modulated sound waves and spread spectrum radar poly-phase code design.

1,086 citations


Journal ArticleDOI
TL;DR: A test for these two parameters is suggested to be a more stringent requirement than the traditional validation parameters to decide acceptability of a predictive QSAR model, especially when a regulatory decision is involved.
Abstract: Validation is a crucial aspect of quantitative structure-activity relationship (QSAR) modeling. The present paper shows that traditionally used validation parameters (leave-one-out Q(2) for internal validation and predictive R(2) for external validation) may be supplemented with two novel parameters r(m)(2) and R(p)(2) for a stricter test of validation. The parameter r(m)(2)((overall)) penalizes a model for large differences between observed and predicted values of the compounds of the whole set (considering both training and test sets) while the parameter R(p)(2) penalizes model R(2) for large differences between determination coefficient of nonrandom model and square of mean correlation coefficient of random models in case of a randomization test. Two other variants of r(m)(2) parameter, r(m)(2)((LOO)) and r(m)(2)((test)), penalize a model more strictly than Q(2) and R(2)(pred) respectively. Three different data sets of moderate to large size have been used to develop multiple models in order to indicate the suitability of the novel parameters in QSAR studies. The results show that in many cases the developed models could satisfy the requirements of conventional parameters (Q(2) and R(2)(pred)) but fail to achieve the required values for the novel parameters r(m)(2) and R(p)(2). Moreover, these parameters also help in identifying the best models from among a set of comparable models. Thus, a test for these two parameters is suggested to be a more stringent requirement than the traditional validation parameters to decide acceptability of a predictive QSAR model, especially when a regulatory decision is involved.

474 citations


Book ChapterDOI
01 Jan 2009
TL;DR: This chapter presents a new adaptive variant of BFOA, where the chemotactic step size is adjusted on the run according to the current fitness of a virtual bacterium, and discusses the hybridization of B FOA with other optimization techniques.
Abstract: Bacterial foraging optimization algorithm (BFOA) has been widely accepted as a global optimization algorithm of current interest for distributed optimization and control BFOA is inspired by the social foraging behavior of Escherichia coli BFOA has already drawn the attention of researchers because of its efficiency in solving real-world optimization problems arising in several application domains The underlying biology behind the foraging strategy of Ecoli is emulated in an extraordinary manner and used as a simple optimization algorithm This chapter starts with a lucid outline of the classical BFOA It then analyses the dynamics of the simulated chemotaxis step in BFOA with the help of a simple mathematical model Taking a cue from the analysis, it presents a new adaptive variant of BFOA, where the chemotactic step size is adjusted on the run according to the current fitness of a virtual bacterium Nest, an analysis of the dynamics of reproduction operator in BFOA is also discussed The chapter discusses the hybridization of BFOA with other optimization techniques and also provides an account of most of the significant applications of BFOA until date

421 citations


Journal ArticleDOI
TL;DR: In this paper, the potential contribution of industrial energy-efficiency technologies and policies to reduce energy use and greenhouse gas emissions to 2030 is discussed, where the authors propose a framework to evaluate the potential of these technologies for mitigating greenhouse gas emission from industry.
Abstract: Industry contributes directly and indirectly (through consumed electricity) about 37% of the global greenhouse gas emissions, of which over 80% is from energy use. Total energy-related emissions, which were 9.9 GtCO2 in 2004, have grown by 65% since 1971. Even so, industry has almost continuously improved its energy efficiency over the past decades. In the near future, energy efficiency is potentially the most important and cost-effective means for mitigating greenhouse gas emissions from industry. This paper discusses the potential contribution of industrial energy-efficiency technologies and policies to reduce energy use and greenhouse gas emissions to 2030.

371 citations


Journal ArticleDOI
TL;DR: In this paper, the thermal conductivity of nanofluid has been determined by model proposed by Patel et al. and the fluid was considered as Newtonian as well as non-Newtonian for a wide range of Reynolds number (Re = 5 to 1500) and solid volume fraction (0.00 ⩽ ϕ⩽ 0.050 ).

322 citations


Journal ArticleDOI
B. Bhatta1
TL;DR: In this article, a study was carried out to identify and analyse the urban growth pattern of Kolkata, India Several statistical methods were applied to recognize and analyse this pattern, which shows increasing dispersed development of the city with the declining population growth rate.
Abstract: Urban growth pattern has a direct influence on urban development processes both at the city and neighbourhood levels, but on the other hand growth pattern is also affected by land and housing policy, current built-up area, available developable area, change in household count, population, economy, and others Remote sensing and GIS techniques can be used to analyse and model the urban growth pattern This study was carried out to identify and analyse the urban growth pattern of Kolkata, India Several statistical methods were applied to recognize and analyse this pattern, which shows increasing dispersed development of the city with the declining population growth rate Apart from the derived results, this study also shows the potentiality of remote sensing and GIS techniques for the analysis of urban growth patterns

294 citations


Journal ArticleDOI
TL;DR: It is noted that arsenic concentration decreased with increasing depth, and was found in two tube wells in Kolkata for 325 and 51 days during 2002-2005, showed 15% oscillatory movement without any long-term trend.
Abstract: Since 1988 we have analyzed 140 150 water samples from tube wells in all 19 districts of West Bengal for arsenic; 48.1% had arsenic above 10 μg/L (WHO guideline value), 23.8% above 50 μg/L (Indian Standard) and 3.3% above 300 μg/L (concentration predicting overt arsenical skin lesions). Based on arsenic concentrations we have classified West Bengal into three zones: highly affected (9 districts mainly in eastern side of Bhagirathi River), mildly affected (5 districts in northern part) and unaffected (5 districts in western part). The estimated number of tube wells in 8 of the highly affected districts is 1.3 million, and estimated population drinking arsenic contaminated water above 10 and 50 μg/L were 9.5 and 4.2 million, respectively. In West Bengal alone, 26 million people are potentially at risk from drinking arsenic-contaminated water (above 10 μg/L). Studying information for water from different depths from 107 253 tube wells, we noted that arsenic concentration decreased with increasing depth. Measured arsenic concentration in two tube wells in Kolkata for 325 and 51 days during 2002–2005, showed 15% oscillatory movement without any long-term trend. Regional variability is dependent on sub-surface geology. In the arsenic-affected flood plain of the river Ganga, the crisis is not having too little water to satisfy our needs, it is the crisis of managing the water.

276 citations


Journal ArticleDOI
TL;DR: Several simulation examples as well as comparisons of DE with two other state-of-the-art optimization techniques over the same problems demonstrate the superiority of the proposed approach especially for actuating fractional-order plants.

271 citations


Journal ArticleDOI
TL;DR: The traditional uses, phytochemistry and therapeutic reports on different parts of N. nucifera viz. the seeds, rhizomes, leaves and flowers are reviewed.
Abstract: ObjectivesNelumbo nucifera Gaertn. (Nymphaeaceae), also known as sacred lotus, is a well known medicinal plant. This article reviews the traditional uses, phytochemistry and therapeutic reports on different parts of N. nucifera viz. the seeds, rhizomes, leaves and flowers. This review also describes various compounds isolated from different parts of this plant and the therapeutic benefits derived from those phytoconstituents. Key findings There are several therapeutic benefits of this plant for which different parts are used. The extracts of rhizomes, seeds, flowers and leaves have been reported to have varied therapeutic potential. Several bioactive compounds have been derived from these plant parts belonging to different chemical groups, including alkaloids, flavonoids, glycosides, triterpenoid, vitamins etc., which all have their own therapeutic impact. Thus, the pharmacological effects and various active ingredients of different parts of N. nucifera are well understood. Summary In this review we explore the current pharmaceutical, phytochemical and pharmacological knowledge about this well known plant species as well as several emerging aspects for research on N. nucifera.

268 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that the multiplicative semigroup ℤn and its subgroup Un is complete if and only if n = 1,2,4,p or 2p, where p is a Fermat prime.
Abstract: The undirected power graph G(S) of a semigroup S is an undirected graph whose vertex set is S and two vertices a,b∈S are adjacent if and only if a≠b and am=b or bm=a for some positive integer m. In this paper we characterize the class of semigroups S for which G(S) is connected or complete. As a consequence we prove that G(G) is connected for any finite group G and G(G) is complete if and only if G is a cyclic group of order 1 or pm. Particular attention is given to the multiplicative semigroup ℤn and its subgroup Un, where G(Un) is a major component of G(ℤn). It is proved that G(Un) is complete if and only if n=1,2,4,p or 2p, where p is a Fermat prime. In general, we compute the number of edges of G(G) for a finite group G and apply this result to determine the values of n for which G(Un) is planar. Finally we show that for any cyclic group of order greater than or equal to 3, G(G) is Hamiltonian and list some values of n for which G(Un) has no Hamiltonian cycle.

266 citations


Journal ArticleDOI
TL;DR: Nanocrystalline copper(II) oxide efficiently catalyzed the conjugate addition of aliphatic amines to α,β-unsaturated compounds to produce β-amino compounds with excellent yields under mild reaction conditions.

Journal ArticleDOI
TL;DR: This paper presents a mathematical analysis of the chemotactic step in BFOA from the viewpoint of the classical gradient descent search, and investigates an interesting application of the proposed adaptive variants of BFI to the frequency-modulated sound wave synthesis problem, appearing in the field of communication engineering.
Abstract: In his seminal paper published in 2002, Passino pointed out how individual and groups of bacteria forage for nutrients and how to model it as a distributed optimization process, which he called the bacterial foraging optimization algorithm (BFOA). One of the major driving forces of BFOA is the chemotactic movement of a virtual bacterium that models a trial solution of the optimization problem. This paper presents a mathematical analysis of the chemotactic step in BFOA from the viewpoint of the classical gradient descent search. The analysis points out that the chemotaxis employed by classical BFOA usually results in sustained oscillation, especially on flat fitness landscapes, when a bacterium cell is close to the optima. To accelerate the convergence speed of the group of bacteria near the global optima, two simple schemes for adapting the chemotactic step height have been proposed. Computer simulations over several numerical benchmarks indicate that BFOA with the adaptive chemotactic operators shows better convergence behavior, as compared to the classical BFOA. The paper finally investigates an interesting application of the proposed adaptive variants of BFOA to the frequency-modulated sound wave synthesis problem, appearing in the field of communication engineering.

Journal ArticleDOI
TL;DR: An open superstructure: A Pd/CeO2 catalyst prepared by solution combustion synthesis is three to five times more active for CH4 combustion than the best conventional palladium-based systems.
Abstract: An open superstructure: A Pd/CeO2 catalyst prepared by solution combustion synthesis is three to five times more active for CH4 combustion than the best conventional palladium-based systems. The catalyst contains an ordered, stable Pd-O-Ce surface superstructure (see picture; cyan arrow is a square-planar Pd site, red arrow is an undercoordinated O atom) and is an example of ultra-highly dispersed, stable PdO within an oxide carrier.

Journal ArticleDOI
TL;DR: The main objective of this paper is to introduce a most promising pattern recognition technique called cross-correlation aided SVM based classifier, which has been utilized for binary classification of EEG signals.
Abstract: Over the last few decades pattern classification has been one of the most challenging area of research. In the present-age pattern classification problems, the support vector machines (SVMs) have been extensively adopted as machine learning tools. SVM achieves higher generalization performance, as it utilizes an induction principle called structural risk minimization (SRM) principle. The SRM principle seeks to minimize the upper bound of the generalization error consisting of the sum of the training error and a confidence interval. SVMs are basically designed for binary classification problems and employs supervised learning to find the optimal separating hyperplane between the two classes of data. The main objective of this paper is to introduce a most promising pattern recognition technique called cross-correlation aided SVM based classifier. The idea of using cross-correlation for feature extraction is relatively new in the domain of pattern recognition. In this paper, the proposed technique has been utilized for binary classification of EEG signals. The binary classifiers employ suitable features extracted from crosscorrelograms of EEG signals. These cross-correlation aided SVM classifiers have been employed for some benchmark EEG signals and the proposed method could achieve classification accuracy as high as 95.96% compared to a recently proposed method where the reported accuracy was 94.5%.

Journal ArticleDOI
TL;DR: In this article, two most potential multi-criteria decision-making (MCDM) approaches are compared and compared relative performance for a given material selection application for different material selection problems.

Journal ArticleDOI
03 Feb 2009-Langmuir
TL;DR: Results of physicochemical studies on the interaction of bovine serum albumin (BSA) with alkyltrimethylammonium bromide (ATAB), pentaethylene glycol mono-n-dodecyl ether (C12E5), and sodium dodecyl sulfate (SDS) under the experimental conditions of phosphate buffer at pH 7 in the presence of 10 mM sodium bromides have been presented and discussed.
Abstract: In this paper, results of physicochemical studies on the interaction of bovine serum albumin (BSA) with alkyltrimethylammonium bromide (ATAB), pentaethylene glycol mono-n-dodecyl ether (C12E5), and sodium dodecyl sulfate (SDS) under the experimental conditions of phosphate buffer at pH 7 in the presence of 10 mM sodium bromide (NaBr), maintaining the ionic strength of the overall solution at μ = 0.015 M, have been presented and discussed. Here, BSA−ATAB corresponds to a polyion−surfactant system bearing opposite charges. BSA precipitated out of the solution on addition of ATAB solution over a certain range of ATAB concentration, the concentration range being dependent on the particular member of the ATAB family. In our earlier reports on the precipitation of oppositely charged polymer−surfactant, the tensiometric profile for surfactant addition in polymer solution differed significantly from that expected from addition of surfactant in the dispersion medium. In the present study, the precipitation process...

Journal ArticleDOI
01 Mar 2009
TL;DR: An attempt has been made to review the major applications of GAs to the domain of medical image segmentation and shows that the genetic algorithmic framework prove to be effective in coming out of local optima.
Abstract: Genetic algorithms (GAs) have been found to be effective in the domain of medical image segmentation, since the problem can often be mapped to one of search in a complex and multimodal landscape. The challenges in medical image segmentation arise due to poor image contrast and artifacts that result in missing or diffuse organ/tissue boundaries. The resulting search space is therefore often noisy with a multitude of local optima. Not only does the genetic algorithmic framework prove to be effective in coming out of local optima, it also brings considerable flexibility into the segmentation procedure. In this paper, an attempt has been made to review the major applications of GAs to the domain of medical image segmentation.

Journal ArticleDOI
TL;DR: In this article, the effect of different operating and processing variables viz. reaction temperature, molar ratio of alcohol to oil, the type of alcohol used, type of catalyst used and its concentration, reaction time, presence of moisture and free fatty acids (FFA) content on transesterification and different pretreatment procedures have been thoroughly reviewed.
Abstract: Methods of pretreatment and transesterification of waste cooking oils (WCOs) to yield fatty acid alkyl esters (biodiesel) qualitatively comparable with fossil diesel fuels have been discussed. The effect of different operating and processing variables viz. reaction temperature, molar ratio of alcohol to oil, the type of alcohol used, type of catalyst used and its concentration, reaction time, presence of moisture and free fatty acids (FFA) content on transesterification and different pretreatment procedures have been thoroughly reviewed. The recent advancements involving both esterification and transesterification for enhancing the overall yield of biodiesel have been discussed.

Journal ArticleDOI
01 Jan 2009
TL;DR: Extensive performance comparison among the new method, a recently developed genetic-fuzzy clustering technique and the classical fuzzy c-means algorithm over a test suite comprising ordinary grayscale images and remote sensing satellite images reveals the superiority of the proposed technique in terms of speed, accuracy and robustness.
Abstract: This article proposes an evolutionary-fuzzy clustering algorithm for automatically grouping the pixels of an image into different homogeneous regions. The algorithm does not require a prior knowledge of the number of clusters. The fuzzy clustering task in the intensity space of an image is formulated as an optimization problem. An improved variant of the differential evolution (DE) algorithm has been used to determine the number of naturally occurring clusters in the image as well as to refine the cluster centers. We report extensive performance comparison among the new method, a recently developed genetic-fuzzy clustering technique and the classical fuzzy c-means algorithm over a test suite comprising ordinary grayscale images and remote sensing satellite images. Such comparisons reveal, in a statistically meaningful way, the superiority of the proposed technique in terms of speed, accuracy and robustness.

Journal ArticleDOI
TL;DR: In this article, an improved particle swarm optimization (IPSO) technique is proposed to solve the problem of optimal power generation to short-term hydrothermal scheduling problem, using improved PSO technique, which is applied on a multi-reservoir cascaded hydro-electric system having prohibited operating zones and a thermal unit with valve point loading.

Journal ArticleDOI
TL;DR: In this paper, a brief review of the progress made in the field of radon measurements in earth sciences, specially in predicting earthquakes, is presented, and the models proposed in relating precursor time, epicentral distance, magnitude of earthquake have also been discussed.

Journal ArticleDOI
TL;DR: Three different evolutionary algorithms such as (GA), (PSO) and (DE) have been applied for synthesis of a four-bar mechanism minimising the error between desired and obtained coupler curve and performance of DE is found to be the best.

Journal ArticleDOI
TL;DR: This paper presents an attempt to improve the search performance of HS by hybridizing it with Differential Evolution (DE) algorithm and has been compared with classical HS, the global best HS, and a very popular variant of DE over a test-suite of six well known benchmark functions and one interesting practical optimization problem.
Abstract: Harmony Search (HS) is a recently developed stochastic algorithm which imitates the music improvisation process. In this process, the musicians improvise their instrument pitches searching for the perfect state of harmony. Practical experiences, however, suggest that the algorithm suffers from the problems of slow and/or premature convergence over multimodal and rough fitness landscapes. This paper presents an attempt to improve the search performance of HS by hybridizing it with Differential Evolution (DE) algorithm. The performance of the resulting hybrid algorithm has been compared with classical HS, the global best HS, and a very popular variant of DE over a test-suite of six well known benchmark functions and one interesting practical optimization problem. The comparison is based on the following performance indices - (i) accuracy of final result, (ii) computational speed, and (iii) frequency of hitting the optima.

Journal ArticleDOI
TL;DR: In this article, a diesel engine with hydrogen flow rate at 0.15 kg/h was tested using a timed manifold induction system which is electronically controlled to deliver hydrogen on to the intake manifold.

Journal ArticleDOI
TL;DR: In this paper, a comprehensive model of an electrostatically actuated microcantilever beam separated from the ground plane by relatively larger gap is formulated accounting for the nonlinearities of the system arising out of electric forces, geometry of the deflected beam and the inertial terms.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the effects of incorporating a facultative anaerobic hot spring bacterium on the microstructure of a cement-sand mortar and found that the bacterial treatment promoted uniform distribution of silicate phases and increased the calcium/silicon ratio within CSH gel of the matrices.
Abstract: Microbial modified mortar or concrete has become an important area of research for high-performance construction materials. This study investigates the effects of incorporating a facultative anaerobic hot spring bacterium on the microstructure of a cement–sand mortar. Environmental scanning electron microscopic (ESEM) views and image analysis (IA) of the bacteria modified mortar (thin-section) showed significant textural differences with respect to the control (without bacteria) samples. X-ray diffraction (XRD) study confirmed the formation of new phases of silicates (Gehlenite) within the matrix of such mortar material, which causes an improvement in the strength of the material. Electron probe microstructure analysis (EPMA) suggested that the bacterial treatment promoted uniform distribution of silicate phases and increased the calcium/silicon ratio within CSH gel of the matrices. The bacterium is found to leach a novel protein, which is capable of isolating silica from its source. The addition of such isolated protein, instead of the bacteria, into mortar also improves the strength of mortar.

Journal ArticleDOI
TL;DR: The diabetic rats exhibited lower activities of superoxide dismutase, catalase, and reduced glutathione content in hepatic and renal tissues as compared with normal rats, and the activities of SOD, CAT, and GSH were found to be increased in extract treated diabetic rats in selected tissues.

Journal ArticleDOI
TL;DR: In this article, the performance of micro-electro-discharge machining of titanium alloys has been evaluated using the Taguchi method and the ANOVA and S/N ratio graph.
Abstract: Being a difficult-to-cut material, titanium alloy suffers poor machinability for most cutting processes, especially the drilling of micro-holes using traditional machining methods. Although electrical discharge machining (EDM) is suitable for machining titanium alloys, selection of machining parameters for higher machining rate and accuracy is a challenging task in machining micro-holes. The present research attempts to optimize micro-EDM process parameters for machining Ti-6Al-4V super alloy. To verify the optimal micro-EDM process parameters settings, metal removal rate (MRR), tool-wear rate (TWR), over cut (OC) and taper were chosen as observed performance criteria. In addition, four independent parameters such as peak current, pulse-on time, flushing pressure, and duty ratio were adopted for evaluation by the Taguchi method. From the ANOVA and S/N ratio graph, the significant process parameters and the optimal combination level of machining parameters were obtained. It is seen that machining performances are affected mostly by the peak current and pulse-on time during micro-electro-discharge machining of titanium alloy. Mathematical models have been developed to establish the relationship between various significant process parameters and micro-EDM performance criteria. In-depth studies have also been made to examine the influence of various process parameters on the white layer and surface topography through SEM micrographs of machined micro-hole.

Journal ArticleDOI
TL;DR: A modified differential evolution based fuzzy clustering technique, using real-coded encoding of the cluster centres is used for this purpose and results demonstrating the effectiveness of the proposed technique are provided.

Journal ArticleDOI
TL;DR: In this article, a genetic algorithm-based method was used to determine optimal location and size of the distributed generations to be placed in radial, as well as networked, systems with an objective to minimize the power loss.
Abstract: This article presents a genetic algorithm-based method to determine optimal location and size of the distributed generations to be placed in radial, as well as networked, systems with an objective to minimize the power loss. Several simulation studies have been conducted on radial feeders, as well as networked systems, considering single-distributed generation and multiple-distributed generations separately to minimize the power loss of the system subjected to no voltage violation at any of the buses. Simulation results are given, and the results are compared with the results of Wang and Hashem Nehrir [“Analytical approaches for optimal placement of distributed generation sources in power systems,” IEEE Trans. Power Syst., Vol. 19, No. 4, pp. 2068–2076, November 2004] and Gozel et al. [“Optimal placement and sizing of distributed generation on radial feeder with different static load model,” Proc. of IEEE International Conference on Future Power Systems (EPS 2005), pp. 1–6, Amsterdam, The Netherl...