Indian Institute of Technology Bhubaneswar

About: Indian Institute of Technology Bhubaneswar is a education organization based out in Bhubaneswar, India. It is known for research contribution in the topics: Large Hadron Collider & Computer science. The organization has 1185 authors who have published 3132 publications receiving 48832 citations.

Enhanced Thermoelectric Performance in Hf-Free p-Type (Ti, Zr)CoSb Half-Heusler Alloys

Abstract: High thermal conductivity and exorbitant cost of Hf has for a long time limited the prospects of half-Heusler (HH) alloys for applicability in thermoelectric (TE) energy conversion devices. This work demonstrates the implication of nanostructuring and efficacy of p-type acceptor dopant in (Ti,Zr)CoSb based HH alloys for enhancing the figure of merit (ZT) while eliminating the use of Hf. A series of (Ti,Zr)CoSb1−x(Si,Sn)x HH composition was synthesized using arc-melting and consolidated employing spark plasma sintering (SPS). The optimal doping of acceptor dopants, namely, Si and Sn significantly improves the power factor and strengthens the phonon scattering resulting in an enhanced TE performance with maximum ZT of 0.26 and 0.5 at 873 K, obtained for TiCoSb0.8Sn0.2 and ZrCoSb0.8Sn0.2, respectively. For further optimization, microstructural modifications by fine-tuning of the Ti to Zr ratio induces strain field effects and mass fluctuation in (Ti,Zr)CoSb0.8Sn0.2 compositions, which remarkably introduces additional phonon scattering resulting in maximum ZT ∼ 0.8 at 873 K for the best performing Zr0.5Ti0.5CoSb0.8Sn0.2 compound. The current study provides a better understanding of p-type dopants in HH materials by which prospective high TE performance can be obtained in low-cost Hf-free p-type (Ti,Zr)CoSb half-Heusler alloys.

Applications of Remote Sensing and GIS in Water Quality Monitoring and Remediation: A State-of-the-Art Review

Abstract: Recent advancements in the field of remote sensing and geographic information systems (GIS) have made it possible to conduct large-scale water remediation studies. Using improved spectral and spatial resolution sensors and geospatial modeling techniques, water quality parameters such as chlorophyll-a, algae bloom, turbidity, suspended sediments, and mineral content in water bodies including groundwater are being monitored at low cost and with greater accuracy. Integration of these technologies with field monitoring have successfully aided in identification of contamination zones and sources of contamination, and for developing strategies for remediation. High-resolution mapping of contamination zones will further help in allocating remediation efforts to the critically affected areas. This chapter investigates the status of ongoing research in the domain of remote sensing and GIS for water quality monitoring and management, and remediation of water resources.

Observation of a new structure near 10 .75 GeV in the energy dependence of the e + e - → ϒ ( nS) π + π - ( n = 1 , 2 , 3) cross sections

Abstract: We report a new measurement of the e+e−→ ϒ(nS)π+π− (n = 1, 2, 3) cross sections at energies from 10.52 to 11.02 GeV using data collected with the Belle detector at the KEKB asymmetric-energy e+e− collider. We observe a new structure in the energy dependence of the cross sections; if described by a Breit-Wigner function its mass and width are found to be $$ M=\left(10752.7\pm {5.9}_{-1.1}^{+0.7}\right)\mathrm{MeV}/{c}^2 $$ and $$ \Gamma =\left({35.5}_{-11.3\kern0.5em -3.3}^{+17.6+3.9}\right) $$ MeV, where the first error is statistical and the second is systematic. The global significance of the new structure including systematic uncertainty is 5.2 standard deviations. We also find evidence for the e+e−→ ϒ (1S)π+π− process at the energy 10.52 GeV, which is below the B $$ \overline{B} $$ threshold.

Physicochemical properties and supercapacitor behavior of electrochemically synthesized few layered graphene nanosheets

Abstract: The study emphasizes on the scalable production and comparison of few layered graphene nanosheets (FLGNSs). The FLGNSs have been electrochemically synthesized by anionic intercalation from three different acids of 1 M of H2SO4 (S1), 1-M HClO4 (C1), and 1-M HNO3 (N1). The size distribution and stability of the as-prepared FLGNSs colloidal have been analyzed thoroughly. A yield of around 50 % was found irrespective of experimental condition. A mixed phase of graphene and its oxide form has been confirmed X-ray diffraction patterns. C1- and N1-conditioned FLGNSs had higher oxygenation as compared to S1, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The disorderness in the FLGNSs has been analyzed by Raman spectra. The aromaticity, surface hydroxylation, and oxygenation of the as-synthesized FLGNSs due to electrochemical reactions have been confirmed by Fourier transform infrared spectroscopy. The UV-visible spectra of FLGNSs colloidal show the electronic transition of π-π* as well as n-π*. From morphological studies, the layered and crumpled edges of the exfoliated FLGNSs have been revealed. Again, from the probe conductivity analysis, the measured conductivity of the dispersed sulfate-, perchlorate-, and nitrate-intercalated FLGNSs has been found with a decreasing trend from 1.652, 0.315, to 0.300 mS/cm for S1, C1, and N1 conditions, respectively, due to increasing of oxygen endowment in the graphene sheets. Detailed supercapacitor investigations demonstrated that the S1-conditioned FLGNSs show enhanced supercapacitor performance than C1 and N1. It possesses a maximum energy density of 20 Wh kg−1 and a maximum power density of 2.5 kW kg−1.

Pareto optimization of cognitive radio parameters using multiobjective evolutionary algorithms and fuzzy decision making

Abstract: The design of cognitive radio engine aims at adapting the radio parameters to a predefined set of objective functions in communication system and may be formulated as a constrained multiobjective optimization problem. In the proposed work, an efficient design of orthogonal frequency division multiplexing based cognitive radio is carried out using multiobjective evolutionary algorithms. The performances of different algorithms are assessed and compared using three statistical metrics. The simulation results show that our proposed approach outperforms other algorithms while designing a cognitive radio engine. Our proposed approach which is based on the concept of cat swarm optimization, not only efficiently computes but also finds better nondominating solutions. In this paper, multiobjective evolutionary algorithms are applied to the parameter adaptation of a OFDM based cognitive radio engine. The spectral interference between primary and cognitive users is taken into consideration which plays a major role in communication. Due to heuristic nature of evolutionary algorithms, the stability of the simulation results is verified using different statistical tests. A fuzzy logic based strategy is shown in order to find out a compromised solution on the Pareto front.