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Saxena G.,Government Women Engineering College | Singh D.,University of Rajasthan
International Journal of Modern Physics E | Year: 2013

Encouraged by the success of relativistic mean-field plus BCS (RMF + BCS) approach for the description of the ground state properties of the chains of isotopes of proton magic nuclei with proton number Z = 8, 20, 28, 50 and 82 as well as those of proton sub-magic nuclei with Z = 40, we have further employed it, in an analogous manner, for a detailed calculations of the ground state properties of the neutron magic isotones with neutron number N = 8, 20, 28, 50, 82 and 126 as well as those of neutron sub-magic isotones with N = 40 using the TMA force parametrizations in order to explore low lying resonance and other exotic phenomenon near drip-lines. The results of these calculations for wave function, single particle pairing gaps etc. are presented here to demonstrate the general validity of our RMF + BCS approach. It is found that, in some of the proton-rich nuclei in the vicinity of the proton drip-line, the main contribution to the pairing correlations is provided by the low-lying resonant states, in addition to the contributions coming from the states close to the Fermi surface, which results extended proton drip-line for isotonic chain. © 2013 World Scientific Publishing Company.

Singh D.,University of Rajasthan | Saxena G.,Government Women Engineering College
International Journal of Modern Physics E | Year: 2012

Inspired by recent experimental studies of two-proton radioactivity in the light-medium mass region, we have employed relativistic mean-field plus state-dependent BCS approach (RMF+BCS) to study the ground state properties of selected even-Z nuclei in the region 20 ≤ Z ≤ 40. It is found that the effective potential barrier provided by the Coulomb interaction and that due to centrifugal force may cause a long delay in the decay of some of the nuclei even with small negative proton separation energy. This may cause the existence of proton-rich nuclei beyond the proton drip-line. Nuclei 38Ti, 42Cr, 45Fe, 48Ni, 55Zn, 60Ge, 63, 64Se, 68Kr, 72Sr and 76Zr are found to be the potential candidates for exhibiting two-proton radioactivity in the region 20 ≤ Z ≤ 40. The reliability of these predictions is further strengthened by the agreement of the calculated results for the ground state properties such as binding energy, one- and two-proton separation energy, proton and neutron radii, and deformation with the available experimental data for the entire chain of the isotopes of the nuclei in the region 20 ≤ Z ≤ 40. © 2012 World Scientific Publishing Company.

Dhaka R.,Government Women Engineering College
Proceedings - 2014 6th International Conference on Computational Intelligence and Communication Networks, CICN 2014 | Year: 2014

In this work, a highly birefringent photonic crystal fiber with ultra low confinement loss using silica is proposed. The birefringence is achieved by introducing the asymmetry along the radial axis. The symmetric cladding structure results in very low confinement loss by limiting the light in the core region. The proposed design is analyzed and simulated using FDTD simulation software and the fiber shows high birefringence (0.0073) and ultra low confinement loss (0.003 dB/km) at 1.55μm wavelength, which makes the photonic crystal fiber endlessly single mode fiber and highly polarization maintaining. © 2014 IEEE.

Verma K.,Petronas University of Technology | Hasbullah H.,Petronas University of Technology | Kumar A.,Government Women Engineering College
Wireless Personal Communications | Year: 2013

Privacy and Security have become an indispensable matter of attention in the Vehicular Ad-Hoc Network, which is vulnerable to many security threats these days. One of them is the Denial of Service (DoS) attacks, where a malicious node forges a large number of fake identities, i.e.; Internet Protocol (IP) addresses in order to disrupt the proper functioning of fair data transfer between two fast-moving vehicles. In this paper, a distributed and robust approach is presented to defend against DoS attacks. In this proposed scheme, the fake identities of malicious vehicles are analyzed with the help of consistent existing IP address information. Beacon packets are exchanged periodically by all the vehicles to announce their presence and to become aware of the next node. Each node periodically keeps a record of its database by exchanging the information in its environment. If some nodes observe that they have similar IP addresses in the database, these similar IP addresses are identified as DoS attacks. However, it can be expected that security attacks are likely to increase in the coming future due to more and more wireless applications being developed onto the well-known exposed nature of the wireless medium. In this respect, the network availability is exposed to many types of attacks. A DoS attack on the network availability is being elaborated in this paper. A model of a product interaction for DoS prevention has been developed called "IP-CHOCK" that will lead to the prevention of DoS attacks. The proposed approach will be able to locate malicious nodes without the requirement of any secret information exchange and special hardware support. Simulation results demonstrate that the detection rate increases when optimal numbers of nodes are forged by the attackers. © 2013 Springer Science+Business Media New York.

Misra R.,Malaviya National Institute of Technology, Jaipur | Bansal V.,Government Women Engineering College | Agrawal G.D.,Malaviya National Institute of Technology, Jaipur | Mathur J.,Malaviya National Institute of Technology, Jaipur | Aseri T.,Government Engineering College
Energy and Buildings | Year: 2013

Thermal performance of earth air tunnel heat exchanger (EATHE) under transient operating conditions has been evaluated for predominantly hot and dry climate of Ajmer (India) using experimental and computational fluid dynamics modeling. Effect of time duration of continuous operation and thermal conductivity of soil on thermal performance of EATHE under transient conditions has been analyzed. Results show that the transient thermal performance of EATHE is significantly dependent on thermal conductivity of the soil and duration of its continuous operation. Under steady state condition, a drop of 18.8 °C is obtained in air passing through EATHE having 0.1 m diameter and 60 m length, at 5 m s-1 flow velocity, whereas, the transient analysis shows that for soil having thermal conductivity of 0.52 W m-1 K-1, the cooling of air reduces from 18.7 °C to 16.6 °C, after 24 h of continuous operation. Change in cooling effect after 24 h of operation for soil thermal conductivity of 2.0 W m-1 K-1 and 4.0 W m -1 K-1, reduced from 18.8 °C to 18.5 °C and 18.8 °C to 18.7 °C respectively. The analyzed cases have shown the range of derating to be as minimal as 0% to as high as 64%, which if ignored while designing may lead to poor performance of earth air heat exchangers. © 2012 Elsevier B.V. All rights reserved.

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