4,783 research outputs found

    Crystal structure changes in Ni3Al and its anomalous temperature dependence of strength

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    The existence of a structural transformation in Ni3Al alloys established earlier through X-ray diffraction, dilatometry and TEM investigations are summarised. The results obtained are discussed through a model proposed. The L12 structure appears to transform to another L12 or to a DO22 structure during heating. Such a transformation starts at around 700°C and seems to complete around 1100°C. In the temperature range 700-1100°C both phases coexist. This causes a tetragonal distortion of the L12 lattice giving rise to a tweed morphology in TEM observations. The flow stress studies indicate that the anomalous strengthening behaviour is not only due to the dislocation kind of mechanism as proposed in the literature but also due to the structural changes noticed in this work

    Service quality gap analysis in private sector bank - a customer perspective

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    The present study evaluates the customer perceptions of service quality in selected private sector banks. Data was collected from 200 customers of ICICI and CUB using structured questionnaire. Gap analysis and Multi regression were used fro analysis of data. The result shows that the dimension of service quality such as Empathy and Accessibility has more gap, as the customer expectations are high to their perceived service. The result also indicates that Empathy-Reliability-Assurance positively influences the service quality. The study implies that bank should reduce the service gap to deliver superior quality of service to retain existing customers as well as to attract new customers.Service quality, Service Gap, Multi Regression

    Thermal evidence for the structural instability in Ni3 Al alloys

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    The thermal expansion coefficient (¿) and calorimetric data were obtained as a function of temperature in order to clarify some of the significant variations reported with regard to these values in the literature. Stoichiometric and off-stoichiometric compositions of Ni3Al alloys (with and without boron addition) were investigated. Dilatometric experiments were performed on all the alloys and the ¿ values were estimated over the temperature range from ambient to 1000°C. Two runs were made on each sample under different initial conditions and differences in ¿ values were noticed. The results were analysed based on our earlier X-ray diffraction results. Additional isothermal dilatometric tests were also carried out and a significant volume change was noticed (0.45% contraction) when the alloy quenched from 1000°C was heated to 600°C and held for a long duration. The calorimetric data were obtaindd over the same range of temperature and enthalpy changes, though less distinct, were noticed at around 360, 660 and 900°C. The variations seen further augment our earlier results on the instability of the L12 structure and the existence of a structural transformatio

    Implementation of AES using biometric

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    Mobile Adhoc network is the most advanced emerging technology in the field of wireless communication. MANETs mainly have the capacity of self-forming, self-healing, enabling peer to peer communication between the nodes, without relying on any centralized network architecture. MANETs are made applicable mainly to military applications, rescue operations and home networking. Practically, MANET could be attacked by several ways using multiple methods. Research on MANET emphasizes on data security issues, as the Adhoc network does not befit security mechanism associated with static networks. This paper focuses mainly on data security techniques incorporated in MANET. Also this paper proposes an implementation of Advanced Encryption Standard using biometric key for MANETs. AES implementation includes, the design of most robust Substitution-Box implementation which defines a nonlinear behavior and mitigates malicious attacks, with an extended security definition. The key for AES is generated using most reliable, robust and precise biometric processing. In this paper, the input message is encrypted by AES powered by secured nonlinear S-box using finger print biometric feature and is decrypted using the reverse process

    Genetic diversity studies of cumin (Cuminun cyminum L.) genotypes in western plains of Rajasthan

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    Genetic diversity was studied on fifty-four genotypes of cumin, Cuminum cyminum L. at “Agricultural Research Station, Mandor, Jodhpur” during rabi season 2017-18. The mean squares were found significantly different for all the characters under study, depicting the availability of variability among the study materials. The high magnitude of phenotypic coefficient of variance (PCV) and genotypic coefficient of variance (GCV) for seed yield, primary branches per plant and number of umbels per plant depicted the presence of vast amount of variation for the character along with high heritability (68-97%) combined with higher genetic advances as percentage of means for seed yield. The highest intra-cluster distance was recorded in cluster VI (11.8) along with cluster VII (11.33) and cluster VIII (8.29) depicting large genetic variability among the genotypes of these three clusters. The highest inter-cluster distance was reported among cluster III and VIII (51.97) followed by cluster III and VII (40.07) and cluster IV and cluster VIII (34.77), suggesting wide range of diversity between genotypes of the clusters. Amongst the characters, seed yield contributed the highest towards genetic divergence (47.80%) followed by number of umbel per plant (25.65%), branches per plant (8.60%) and 1000 seed weight (6.64%)

    Mean field analysis of quantum phase transitions in a periodic optical superlattice

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    In this paper we analyze the various phases exhibited by a system of ultracold bosons in a periodic optical superlattice using the mean field decoupling approximation. We investigate for a wide range of commensurate and incommensurate densities. We find the gapless superfluid phase, the gapped Mott insulator phase, and gapped insulator phases with distinct density wave orders.Comment: 6 pages, 7 figures, 4 table

    Electric Field Effect in Diluted Magnetic Insulator Anatase Co:TiO2

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    An external electric field induced reversible modulation of room temperature magnetic moment is achieved in an epitaxial and insulating thin film of dilutely cobalt-doped anatase TiO2. This first demonstration of electric field effect in any oxide based diluted ferromagnet is realized in a high quality epitaxial heterostructure of PbZr0.2Ti0.8O3/Co:TiO2/SrRuO3 grown on (001) LaAlO3. The observed effect, which is about 15% in strength in a given heterostructure, can be modulated over several cycles. Possible mechanisms for electric field induced modulation of insulating ferromagnetism are discussed.Comment: 14 pages, 4 figure

    Viscous Torque and Dissipation in the Inner Region of a Thin Accretion Disk: Implications for Measuring Black Hole Spin

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    We consider a simple Newtonian model of a steady accretion disk around a black hole. The model is based on height-integrated hydrodynamic equations, alpha-viscosity, and a pseudo-Newtonian potential that results in an innermost stable circular orbit (ISCO) that closely approximates the one predicted by GR. We find that the hydrodynamic models exhibit increasing deviations from the standard disk model of Shakura & Sunyaev as disk thickness H/R or the value of alpha increases. The latter is an analytical model in which the viscous torque is assumed to vanish at the ISCO. We consider the implications of the results for attempts to estimate black hole spin by using the standard disk model to fit continuum spectra of black hole accretion disks. We find that the error in the spin estimate is quite modest so long as H/R < 0.1 and alpha < 0.2. At worst the error in the estimated value of the spin parameter is 0.1 for a non-spinning black hole; the error is much less for a rapidly spinning hole. We also consider the density and disk thickness contrast between the gas in the disk and that inside the ISCO. The contrast needs to be large if black hole spin is to be successfully estimated by fitting the relativistically-broadened X-ray line profile of fluorescent iron emission from reflection off an accretion disk. In our hydrodynamic models, the contrast in density and thickness is low when H/R>0.1, sugesting that the iron line technique may be most reliable in extemely thin disks. We caution that these results have been obtained with a viscous hydrodynamic model and need to be confirmed with MHD simulations of radiatively cooled thin disks.Comment: 32 pages, 10 figures; accepted by Ap

    Detection and localization of cotton based on deep neural networks

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    Cotton detection is the localization and identification of the cotton in an image. It has a wide application in robot harvesting.&nbsp; Various modern algorithms use deep learning techniques for detection of fruits/flowers. As per the survey, the topics travelled include numerous algorithms used, and accuracy obtained on using those algorithms on their data set. The limitations and the advantages in each paper, are also discussed. This paper focuses on various fruit detection algorithms- the Faster RCNN, the RCNN, YOLO. Ultimately, a rigorous survey of many papers related to the detection of objects like fruits/flowers, analysis of the assets and faintness of each paper leads us to understanding the techniques and purpose of algorithms. &nbsp

    Fully Invariant and Characteristic Interval-Valued Intuitionistic Fuzzy Dual Ideals of BF-algebras

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    The notion of interval-valued intuitionistic fuzzy sets was first introduced by Atanassov and Gargov as a generalization of both interval-valued fuzzy sets and intuitionistic fuzzy sets. Satyanarayana et. al., applied the concept of interval-valued intuitionistic fuzzy ideals and interval-valued intuitionistic fuzzy dual ideals to BF-algebras. In this paper, we introduce the notion of fully invariant and characteristic interval-valued intuitionistic fuzzy dual ideals of BF-algebras and investigate some of its properties
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