Thapar University

About: Thapar University is a education organization based out in Patiāla, Punjab, India. It is known for research contribution in the topics: Computer science & Cloud computing. The organization has 2944 authors who have published 8558 publications receiving 130392 citations.

ENTRANCE-CHANNEL EFFECTS IN THE DYNAMICAL CLUSTER-DECAY MODEL FOR THE DECAY OF HOT AND ROTATING COMPOUND NUCLEUS 48Cr AT ${\rm E}_{CN}^{*}\approx 60\, {\rm MeV}$

Abstract: The entrance-channel effects in the decay of hot and rotating compound nucleus 48Cr*, formed in symmetric 24Mg+24Mg and asymmetric 36Ar+12C reactions, are studied as collective clusterization process, for emissions of both the light particles (LPs) as well as the intermediate mass fragments (IMFs), with in the dynamical cluster-decay model (DCM). We find that the little differences observed in the decay of equilibrated compound nucleus 48Cr*, formed in the two entrance channels with about the same excitation energy, are not in variance with the Bohr's independence hypothesis. In other words, the present study confirms the entrance-channel independence of the decay of compound nucleus 48Cr* formed due to different target-projectile combinations with similar excitation energies. The collective clusterization process is shown to contain the complete structure of the measured fragment cross sections as well as average total kinetic energies.

Robust non-homomorphic approach for speckle reduction in medical ultrasound images

Abstract: Most existing wavelet-based image denoising techniques are developed for additive white Gaussian noise. In applications to speckle reduction in medical ultrasound (US) images, the traditional approach is first to perform the logarithmic transform (homomorphic processing) to convert the multiplicative speckle noise model to an additive one, and then the wavelet filtering is performed on the log-transformed image, followed by an exponential operation. However, this non-linear operation leads to biased estimation of the signal and increases the computational complexity of the filtering method. To overcome these drawbacks, an efficient, non-homomorphic technique for speckle reduction in medical US images is proposed. The method relies on the true characterisation of the marginal statistics of the signal and speckle wavelet coefficients. The speckle component was modelled using the generalised Nakagami distribution, which is versatile enough to model the speckle statistics under various scattering conditions of interest in medical US images. By combining this speckle model with the generalised Gaussian signal first, the Bayesian shrinkage functions were derived using the maximum a posteriori (MAP) criterion. The resulting Bayesian processor used the local image statistics to achieve soft-adaptation from homogeneous to highly heterogeneous areas. Finally, the results showed that the proposed method, named GNDShrink, yielded a signal-to-noise ratio (SNR) gain of 0.42 dB over the best state-of-the-art despeckling method reported in the literature, 1.73 dB over the Lee filter and 1.31 dB over the Kaun filter at an input SNR of 12.0 dB, when tested on a US image. Further, the visual comparison of despeckled US images indicated that the new method suppressed the speckle noise well, while preserving the texture and organ surfaces.

Recent applications of microwaves in materials joining and surface coatings

Abstract: The conventional methods of manufacturing and materials processing are getting obsolete owing to the higher energy consumptions, large processing times and poor characteristics of processed compone...

A robust ElGamal-based password-authentication protocol using smart card for client-server communication

Abstract: Summary Smart card-based client-server authentication protocol is well popular for secure data exchange over insecure and hostile networks. Recently, Lee et al. put forward an authentication protocol by utilizing ElGamal cryptosystem and proved that it can withstand known security threats. This article evinces that the protocol of Lee et al. is unwilling to protect various important security vulnerabilities such as forgery attack and off-line password-guessing attack. To vanquish these loopholes, this article presents a robust authentication protocol for client-server communication over any insecure networks. The security explanation of our protocol has done through the formal and informal mechanism and its outcome makes sure that the designed protocol is strong enough to resist the known vulnerabilities. In addition, we have simulated our protocol using ProVerif online software and its results certify that our protocol is safe against private information of the client and server. This paper also has made performance estimation of the presented protocol and others, and the outcome favors the presented protocol.