University Hyderabad

Hyderabad, India

University Hyderabad

Hyderabad, India
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Joshi S.S.,University Hyderabad | Ramanaiah O.B.V.,University Hyderabad
Proceedings of 2016 International Conference on ICT in Business, Industry, and Government, ICTBIG 2016 | Year: 2017

An exponential increase in the number of web services over the last few years increases the importance of the service selection task for choosing the best among a group of web services with similar functionalities. Most of the web service selection approaches are service provider perspective based on non-functional properties such as performance, reliability etc. (such attributes known as Quality of Service or QoS). But it has been observed that in any decision support issues in selection, users' feedback (known as Quality of Experience or QoE) plays a crucial role. In this paper, an integrated model has been proposed, based on both QoE and QoS, where the best service selection is made based not only on current QoS values of the services but also users' past experience of using them. Further, the case study has been provided and the results have been analyzed by inducing users' ratings as a QoE factor along with QoS parameters. The results show that the proposed approach, augmented by user's feedback, improves the quality of selection. © 2016 IEEE.

Sundar L.S.,University of Aveiro | Shusmitha K.,University Hyderabad | Singh M.K.,University of Aveiro | Sousa A.C.M.,University of Aveiro
International Communications in Heat and Mass Transfer | Year: 2014

The stable nanodiamond-nickel (ND-Ni) nanocomposite based magnetic nanofluids were prepared by dispersing them into water (W) and ethylene glycol (EG) without adding any surfactant and their electrical conductivity has been investigated experimentally. The nanocomposite was synthesized by an in-situ method and characterized by X-ray diffraction, micro-Raman, high-resolution transmission electron microscopy, and vibrating sample magnetometer. The electrical conductivity investigations were performed in very low particle concentrations of 0.02%, 0.05% and 0.1% in the temperature range from 24. °C to 65. °C. The results indicate that an anomalous increase in electrical conductivity was observed with an increase in particle loadings in both the base fluids of water and ethylene glycol. The enhancement values in electrical conductivity for 0.1% of water based ND-Ni nanofluid are 1339.81% and 853.15% at temperatures of 24. °C and 65. °C, respectively compared to water without particles. Similarly, the enhancement values in electrical conductivity for 0.1% of EG based ND-Ni nanofluid are 199.52% and 200.23% at temperatures of 24. °C and 65. °C, respectively compared to EG without particles. Conventional models, such as the Maxwell model and the Bruggeman correlation were considered for comparison and we observed disagreement. © 2014 Elsevier Ltd.

Naik M.T.,University Hyderabad | Sundar L.S.,University of Aveiro
Heat Transfer Engineering | Year: 2014

The article deals with the transition flow convective heat transfer and friction factor characteristics of water/propylene glycol-based CuO nanofluids flowing in a horizontal circular tube fitted with and without helical inserts. CuO nanoparticles of average particle diameter less than 50 nm were suspended in the base fluid and nanofluids of three different concentrations were prepared. Experiments were also conducted by inserting helical inserts having twist ratio in the range of 0 to 9 and Reynolds number ranging from 2500 to 10,000. The Nusselt number obtained with 0.5% concentration of CuO nanofluids is about 28% higher in a plain tube and is increased further up to 5.4 times over the base fluid when the helical insert with twist ratio 3 is used. In the plane tube the friction factor is increased by 10% and further enhanced to 140% with the usage of helical insert compared to the friction factor obtained with the base fluid alone. The friction factor penalty is very much less compared to the benefit of heat transfer enhancement. Correlations for predicting Nusselt number and friction factor are developed using the experimental data pertaining to CuO nanofluids in a plain tube with and without the helical inserts. © Taylor and Francis Group, LLC.

Vinay Kumar B.,University Hyderabad | Ramprasad E.V.V.,University Hyderabad | Sasikala C.,University Hyderabad | Ramana C.V.,Central University of Costa Rica
International Journal of Systematic and Evolutionary Microbiology | Year: 2013

Two strains (JA575T and JA576T) of orange-to pink-pigmented, rod-shaped, motile and budding phototrophic bacteria were isolated from paddy soils. Both strains contained bacteriochlorophyll a and carotenoids of spirilloxanthin series. Both strains had C18: 1ω7c as the major cellular fatty acid, ubiquinone-10 (Q10) as the main quinone, and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine as polar lipids. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that both strains clustered with species of the genus Rhodopseudomonas in the class Alphaproteobacteria. Strains JA575T and JA576T were genotypically (<35% DNA-DNA relatedness) and phenotypically distinct from each other. Further, both strains showed less than 48% DNA-DNA relatedness with the type strains of all recognized species of the genus Rhodopseudomonas. The molecular evidence is supported by phenotypic evidence. It is proposed that strains JA575T and JA576T be classified as representing two novel species of the genus Rhodopseudomonas with the species names Rhodopseudomonas pentothenatexigens sp. nov. and Rhodopseudomonas thermotolerans sp. nov., respectively. The type strains of the proposed novel species are JA575T (5NBRC 108862T5KCTC15143T) and JA576T (5NBRC 108863T5KCTC 15144T), respectively. © 2013 IUMS.

Ramana C.V.,Central University of Costa Rica | Parag B.,Central University of Costa Rica | Girija K.R.,Central University of Costa Rica | Raghu Ram B.,Central University of Costa Rica | And 2 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2013

Two strains (JC85T and JC108) of Gram-stain-negative, motile bacteria were isolated from endolithic beach sand samples on an oligotrophic medium. Based on the 16S rRNA gene sequence analysis, both strains were identified as belonging to the genus Rhizobium. Strain JC108 had 16S rRNA gene sequence similarity of 100% with Rhizobium pusense NRCPB10T and formed a cluster with this strain. Strain JC85T had 96.9% 16S rRNA gene sequence similarity and was 18% related (based on DNA-DNA hybridization) to Rhizobium borbori DN316T. With other strains of the genus Rhizobium, the 16S rRNA gene sequence similarity was less than 96.3%. Strain JC85T could tolerate up to 3% salinity, fix N2, was resistant to ampicillin (10 mg) and was positive for catalase and oxidase. The major fatty acid was C18: 1ω7c (69%) with minor amounts of C19: 0 cyclo ω8c (8.9%), C16: 0 (6.9%), C12: 0 (5.7%) and C19: 1ω7c/ C19: 1ω6c (2.2%). Polar lipids of strain JC85T include two unidentified aminophospholipids (APL1,2), two unidentified phospholipids (PL1,2), phosphatidylcholine and four unidentified lipids (L1-4). Q-10 is the major quinone of strain JC85T. Based on polyphasic taxonomic analysis, strain JC85T represents a novel species for which, the name Rhizobium subbaraonis JC85T is proposed. The type strain is JC85T (=DSM 24765T=KCTC 23614T). © 2013 IUMS.

Parag B.,Central University of Costa Rica | Sasikala Ch.,University Hyderabad | Ramana Ch.V.,Central University of Costa Rica
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2013

Endolithic metagenome analysis of two beach samples collected form Chilika, Odisha, India indicated rich bacterial diversity. While the metagenome analysis of sample one yielded 16S rRNA gene sequences which represent six phyla and 16 genera, sample two yielded very rich diversity representing 17 phyla and 286 genera. Six species of bacteria were isolated from the endolithic enrichments and most of them have 16S rRNA gene sequence similarity of >99 % with known taxa, except for strain JC140T having <97 % sequence similarity with taxa with valid names. Strain JC140T is Gram-stain-negative and motile. 16S rRNA gene based EzTaxon-e BLAST analysis indicated that strain JC140T is closely related with the type strains of Rhizobium yanglingense SH22623T (96.8 %), R. alkalisoli CCBAU 01393T (96.3 %), R. vignae CCBAU 05176T (96.2 %), R. mesosinicum CCBAU 25010T (96.1 %) and other members of the genus Rhizobium with <96 % sequence similarity. Strain JC140T was characterized based on polyphasic taxonomic analysis. Strain JC140T could tolerate up to 5 % salinity, resistant to rifampicin (10 μg) and was positive for catalase and oxidase. The major fatty acid is summed feature 8 (C18:1ω7c/ C18:1ω6c) with minor amounts of C19:0 cycloω8c, C16:0, C18:0, C17:0cyclo, summed feature 2 (C14:03OH/C16:1 isoI), summed feature 3 (C16:1ω7c/C16:1ω6c) and 2-hydroxyacid of C15:0. Diphosphatidylglycerol, phosphatidylethanol-amine, phosphatidylcholine, phosphatidylglycerol, unidentified lipids (L1, 2), unidentified phospholipid (PL1-4) constitute the polar lipids of strain JC140T. The strain has bacteriohopane derivative (BHD2), diplopterol and two unidentified hopanes (UH1, 2) as major hopanoids. Q-10 is the major quinone of strain JC140T. Based on polyphasic taxonomic analysis, strain JC140T represents a species in the genus Rhizobium for which, the name R. endolithicum sp. nov. is proposed. The type strain is JC140 T (= KCTC32077T = CCUG64352T = MTCC11723 T = HAMBI 2447T). © 2013 Springer Science+Business Media Dordrecht.

Darga Kumar N.,University Hyderabad | Narasimha Rao S.,Indian Institute of Technology Madras
Applied Ocean Research | Year: 2010

This investigation refers to an experimental study on earth pressure mobilization in caissons embedded in soft clay. Based on the results, a contiguous wall made up of embedded caissons in soft clay is proposed to serve as a coastal protection wall. Tests were conducted on model caissons embedded in stiff marine clay. Lateral load tests were carried out on models with embedment depth ratios of L/D=2,3 and 4 at load eccentricity ratios of e/D of 0.5, 1.0, 1.5 and 2.0. Earth pressure cells were embedded into the caissons at various depths. Using a pneumatic type of arrangement, controlled lateral loading was applied. The test results show that these caissons can be loaded to produce lateral deflection in the ratios of 30%-35% expressed in terms of diameter. The capacities are estimated corresponding to lateral deflection ratios of 20%. These results suggest that the lateral capacity is a function of undrained strength (su), embedment depth ratio (L/D) and load eccentricity ratio (e/D). There is a good correlation between lateral load and the maximum earth pressure mobilized. At a higher L/D ratio of 4, the lateral earth pressure is found to be unique function of lateral load irrespective of e/D. A unique relation is established between lateral load and deflection in the normalized form. This relation matches very well with the published field lateral load deflection curves. © 2010 Elsevier Ltd.

Arathi M.,University Hyderabad | Govardhan A.,University Hyderabad
Advances in Intelligent Systems and Computing | Year: 2015

The sequence of values that are measured at time intervals equally spaced is time series data. Finding shapelets within a data set as well as classifying that data based on shapelets is one of the most recent approaches to classification of this data. In the classification using shapelets, Euclidean distance measure is adopted to find dissimilarity between two time series sequences. Though the Euclidean distance measure is known for its simplicity in computation, it has some disadvantages: it requires data to be standardized and it also requires that the two data objects being compared be of the same length. It is sensitive to noise as well. To overcome the problem, Mahalanobis distance measure can be used. In the proposed work, classification of time series data is performed using time series shapelets and used Mahalanobis distance measure which is the measure of distribution between a point and distribution. Correlations between data set is considered. It does not depend on scale. The cost complexity pruning is performed on decision tree classifier. The Mahalanobis distance improves the accuracy of algorithm and cost complexity pruning method reduces the time complexity of testing and classification of unseen data. The experimental results show that the Mahalanobis distance measure leads to more accuracy and due to decision tree pruning the algorithm is faster than existing method. © 2015, Springer International Publishing Switzerland.

Kumar K.P.,University Hyderabad | Khan H.,Koneru Lakshmaiah College of Engineering
International Conference on Electrical, Electronics, Signals, Communication and Optimization, EESCO 2015 | Year: 2015

A novel three dimensional artificial magnetic material named here as Tunable Multi Layer Multi Dielectric High Impedance Surface (TMMD-HIS) is proposed. Three dimensional structures have periodicity along all the three dimensions and the remarkable feature is that these systems have complete band gaps and therefore propagation states are not allowed in any direction. The measurement of its surface properties means to understanding of its transmission coefficient, reflection coefficient and surface wave band gap characteristics. For analysis numerical technique of Finite Element Method is used. The results obtained in HFSS simulation software are presented. © 2015 IEEE.

Shivali K.,University of Hyderabad | Sasikala C.,University Hyderabad | Ramana C.,University of Hyderabad
Systematic and Applied Microbiology | Year: 2012

Thirty-one members of the genus Marichromatium were analysed based on multilocus sequence analysis (MLSA) of four concatenated protein-coding genes (fusA, pufM, dnaK, recA) along with the internal transcribed spacer (ITS; 16S-23S rRNA) region and 16S rRNA gene. The restriction patterns obtained from the in silico analysis of the concatenated sequences were good barcodes for the identification of Marichromatium spp. Distinct phenotypic, chemotaxonomic and molecular differences allowed the separation of Marichromatium fluminis JA418T into a new genus in the family Chromatiaceae, for which we propose the name Phaeochromatium fluminis gen. nov. comb. nov. © 2012 Elsevier GmbH.

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