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Shaikh M.W.,Devi Ahilya University | Mansuri I.,Devi Ahilya University | Mansuri I.,Indore Institute of Science and Technology | Varshney D.,Devi Ahilya University
AIP Conference Proceedings | Year: 2014

Polycrystalline sample of single-phase La0.8Sm0.05K0.15MnO3 perovskite compound have been synthesized by solid-state reaction route. X-ray diffraction patterns accompanied by Rietveld-refined crystal structure parameters reveal the rhombohedral structure with space group R 3C. Electrical resistivity infers transition from metallic to insulator phase at 537 K. The application of magnetic field of 8 T, suppresses the resistivity. The metallic resistivity is retraced by considering electron-phonon, electron-electron and electron-spin-fluctuation interactions while insulating behaviour is analysed with small polaron conduction model. © 2014 AIP Publishing LLC.

Varshney M.A.,M B Khalsa College | Shukla S.,Devi Ahilya University | Sen S.,Devi Ahilya University | Sen S.,Indore Institute of Science and Technology | Varshney D.,Devi Ahilya University
Journal of Plasma Physics | Year: 2013

This paper presents the effect of self-focusing on a circularly polarized beam propagating along the static magnetic field when the extraordinary and ordinary modes are present simultaneously for relativistic intensities. The nonlinearity in the dielectric function arises on account of the relativistic variation of mass, which leads to the mutual coupling of the two modes that support the self-focusing of each other. The propagation and focusing of the first mode affects the propagation and focusing of the second mode. The fact that the two modes are laser-intensity dependent leads to cross-focusing. Dynamics of one laser beam affects the dynamics of the second laser beam. When both the beams or modes are strong, the nonlinearities introduced by the relativistic effect in the presence of the magnetic field are additive in nature, such that one beam can undergo oscillatory self-focusing and other beam simultaneously defocusing and vice versa. The dynamical equation governing the cross-focusing has been set up and a numerical solution has been presented for typical relativistic laser-plasma parameters from a slightly underdense to overdense plasma. Copyright © 2013 Cambridge University Press.

Varshney D.,Devi Ahilya University | Mansuri I.,Devi Ahilya University | Mansuri I.,Indore Institute of Science and Technology | Shaikh M.W.,Devi Ahilya University | Kuo Y.K.,National Dong Hwa University
Materials Research Bulletin | Year: 2013

The effect of Fe and Co doping on structural, electrical and thermal properties of half doped La0.5Ce0.5Mn1-x(Fe, Co)xO3 is investigated. The structure of these crystallizes in to orthorhombically distorted perovskite structure. The electrical resistivity of La0.5Ce0.5MnO3 exhibits metal-semiconductor transition (TMS at ∼225 K). However, La0.5Ce0.5Mn1-xTMxO3 (TM = Fe, Co; 0.0 ≤ x ≤ 0.1) manganites show semiconducting behavior. The thermopower measurements infer hole as charge carriers and electron-magnon as well spin wave fluctuation mechanism are effective at low temperature domain and SPC model fits the observed data at high temperature. The magnetic susceptibility measurement confirms a transition from paramagnetic to ferromagnetic phase. The observed peaks in the specific heat measurements, shifts to lower temperatures and becomes progressively broader with doping of transition metals on Mn-site. The thermal conductivity is measured in the temperature range of 10-350 K with a magnitude in between 10 and 80 mW/cm K. © 2013 Elsevier Ltd. All rights reserved.

Sen S.,Indore Institute of Science and Technology | Varshney M.A.,M B Khalsa College | Varshney D.,Devi Ahilya University
Applied Physics B: Lasers and Optics | Year: 2014

In the present work, we investigate the distributed regimes of an intense laser beam in a self-consistent plasma channel. As the intensity of the laser beam increases, the relativistic mass effect as well as the ponderomotive expulsion of electrons modifies the dielectric function of the medium due to which the medium exhibits nonlinearity. Based on Wentzel-Kramers-Brillouin and paraxial ray theory, the steady-state solution of an intense, Gaussian electromagnetic beam is studied. A differential equation of the beamwidth parameter with the distance of propagation is derived, including the effects of relativistic self-focusing (SF) and ponderomotive self-channeling. The nature of propagation and radial dynamics of the beam in plasma depend on the power, width of the beam, and Ω p, the ratio of plasma to wave frequency. For a given value of Ω p (<1), the distribution regimes have been obtained in beampower-beamwidth plane, characterizing the regimes of propagation as steady divergence, oscillatory divergence, and SF. The related focusing parameters are optimized introducing plasma density ramp function, and spot size of the laser beam is analyzed for inhomogeneous plasma. This results in overcoming the diffraction and guiding the laser beam over long distance. Numerical computations are performed for typical parameters of relativistic laser-plasma interaction studies. © 2014 Springer-Verlag Berlin Heidelberg.

Sen S.,Indore Institute of Science and Technology | Varshney M.A.,M B Khalsa College | Varshney D.,Devi Ahilya University
High Energy Density Physics | Year: 2014

In the present communication, the steady state propagation of an intense, circularly polarized Gaussian electromagnetic beam in high-density magnetized plasma is studied analytically and numerically. The relativistic oscillation of the mass of the electrons in the field of the pump and longitudinal magnetic field are shown to have a major effect on the dynamics of the propagation of intense electromagnetic wave. The wave equation has been solved under WKB and paraxial approximation by expanding the dielectric tensor for arbitrary large intensity. The propagation of electromagnetic waves in magnetized plasma, in the so-called extraordinary mode has been explicitly considered in the analysis. The variation of beamwidth parameter with distance of propagation has been obtained for chosen values of critical parameters in different regimes. These regimes are steady divergence, oscillatory divergence and self-focusing. Numerical computations are performed for a wide range of dimensionless parameters. It is seen that the laser beamwidth tends to attain a constant value depending upon plasma electron density, axial inhomogeneity and laser irradiance for different strength of magnetic field. Further, enhanced propagation, focusing and penetration of an intense laser beam is evident through plots from slightly underdense to overdense plasma with different types of density profiles. © 2014 Elsevier B.V.

Kumar K.A.,Indore Institute of Science and Technology | Krishna A.V.N.,Navodaya Institute of Technology | Shahu Chatrapati K.,Jawaharlal Nehru University
Smart Innovation, Systems and Technologies | Year: 2016

Wireless sensor Network (WSN) is an emerging technology has significant applications in several important fields like military, agriculture, healthcare, environmental, artificial intelligence and research. All these applications demands high quality data transmission from resource constraint WSNs. But interference is one of the severe problem in WSN which can degrade the quality data transmission. Various interference minimization techniques have been proposed but not results the expected degree of quality enhancement in WSNs. This research paper investigates various types of heterogeneous wireless sensor networks (HTWSN) deployment techniques, interference and its effects, existing interference minimization techniques with limitations. We propose interference minimization (IM) protocol for heterogeneous wireless sensor networks. IM protocol can efficiently minimize the interference and enhance the quality data transmission in WSN. © Springer International Publishing Switzerland 2016.

Anil Kumar K.,Indore Institute of Science and Technology | Krishna A.V.N.,Navodaya Institute of Technology | Shahu Chatrapati K.,Jawaharlal Nehru University
Advances in Intelligent Systems and Computing | Year: 2016

Heterogeneous wireless sensor network (HTWSN) is the most preferable and demanding technology for military applications because of low cost and high performance in terms of high-quality data transmission with low end-to-end delay. HTWSN can be established with variable-configured sensor nodes for detection and monitoring the complex and multitasking events efficiently within the network. But congestion is the most serious issue which may cause high packet loss; increase the number of retransmissions, frequent link failure, and node failure; lower the network life time by increasing the energy consumption; and lower the throughput. Most of existing congestion control protocols are developed for homogeneous wireless sensor network which may not help to achieve high throughput for HTWSN. So we have proposed a new congestion control protocol (CCP) for HTWSNs which can estimate the congestion control degree (CCD) at each node prior to identify the future congested nodes in the network. Accordingly, CCP can enable its load balancing technique effectively and balance the data traffic between the future congested nodes and source node to achieve high-quality data transmission in HTWSN. © Springer Science+Business Media Singapore 2016.

Patel K.,Indore Institute of Science and Technology | Ragha L.,Ramrao Adik Institute of Technology
2015 International Conference on Industrial Instrumentation and Control, ICIC 2015 | Year: 2015

In today's era sharing of secret data over internet has increased widely. Along with increase in frequent information sharing on Internet threat of malicious access also pulls significant attraction. Cryptography and Steganography are solution to this problem. Steganography is a technique to make private or secret data invisible to the world in order to send it over the network securely. In this paper we proposed an algorithm which is in transform domain and simple in calculation. To increase the level of security we encrypt the data before embedding it into the carrier file. We perform discrete wavelet transform on cover image followed by fusion. At last we perform inverse wavelet transform to get stego image. We compare original cover image and stego image; the results we obtained are good as both the images are almost identical. This is proved by high PSNR (Peak Signal to Noise Ratio) values we have obtained. © 2015 IEEE.

Shivhare N.,Indore Institute of Science and Technology
Pollution Research | Year: 2013

A wetland is a complex assemblage of water, substrate, plants, invertebrates (insect larvae and worms) and micro-organisms (bacteria). These are inter-related and help in improving water quality by settling suspended particulate matter, adsorption and ion-exchange on the surfaces of plants, substrate and sediment, uptake and transformation of nutrients by micro-organisms and plants etc. A constructed wetland is a shallow basin filled with a substrate (soil or gravel) and planted with vegetation tolerant of saturated conditions. In the present study the performance of subsurface horizontal flow constructed wetland for treatment of sewage water was investigated. The substrate used is gravel and vegetation is a macrophyte (Typha latifolia) as they are easily available. Environmental related parameters i.e. pH, COD, BOD5, TSS, NH3-N, PO4 nitrate and Fecal coliform count were monitored in one complete macrophyte life cycle at different HRTs. At an optimum HRT of 2 days removal efficiencies of various parameters were in the range COD (95.3%), BOD5(100%), TSS (97.9%) and NH3-N (78.9%). The Fecal coliform showed 2-3 log reduction. The performances of the system indicate that constructed wetland treatment system is a viable option for sewage treatment. The system is cost effective and can be implemented successfully as a decentralized system in urban and rural areas using local resources. Copyright © Em International.

Varun I.,Indore Institute of Science and Technology | Gupta T.K.,Indore Institute of Science and Technology
2013 Nirma University International Conference on Engineering, NUiCONE 2013 | Year: 2013

Static power consumption has became a major problem as we are moving towards finer technologies. Power consumption is one of the top concerns of VLSI circuit design, for which CMOS is the primary technology. However, there is no universal way to avoid tradeoffs between power, delay and area, and thus designers are required to choose appropriate techniques that satisfy application and product needs. We are presenting two low power digital circuits 41 multiplexer and JK master-slave flip-flop designed with ultra low power NAND gates. These NAND gates have been designed with combination of sleepy stack technique with reverse body bias (RBB) and dual threshold CMOS (DTCMOS). On comparison with conventional 41 multiplexer we have achieved maximum of 30% decrement in dynamic power consumption and 59% decrement in power consumption when circuit is in ideal state. This all is achieved on the coast of 55% increment in worst case propagation delay. For JK master-slave flip-flop we are achieving 13% reduction in dynamic power consumption and 99% saving in static power consumption. All simulations have been done on 65nm technology with dual threshold transistors. © 2013 IEEE.

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