A Session based Multiple Image Hiding Technique using DWT and DCT

This work proposes Steganographic technique for hiding multiple images in a color image based on DWT and DCT. The cover image is decomposed into three separate color planes namely R, G and B. Individual planes are decomposed into subbands using DWT. DCT is applied in HH component of each plane. Secret images are dispersed among the selected DCT coefficients using a pseudo random sequence and a Session key. Secret images are extracted using the session key and the size of the images from the planer decomposed stego image. In this approach the stego image generated is of acceptable level of imperceptibility and distortion compared to the cover image and the overall security is high.Comment: 4 pages,16 figures, "Published with International Journal of Computer Applications (IJCA)

Behaviour of the EAS Age Parameter in the Knee Energy Region

Analyzing simulated EAS events generated with the CORSIKA code, the characteristics of lateral distribution of electrons in EAS around the knee energy region of the primary energy spectrum have been studied and compared with experimental observations. The differences between the EGS4 and the NKG output of CORSIKA in respect to electron radial density distribution have been investigated. The relation between lateral and longitudinal age parameters has been studied after introducing the notion of the local age parameter that reflects the profile of the lateral distribution of electrons in EAS. The present analysis motivates the inclusion of the lateral shower age in a multiparameter study of EAS to extract information on hadronic interactions and primary composition.Comment: Talk presented at XVI International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2010), Batavia, IL, USA (28 June - 2 July 2010). 4 pages, 5 figure

Analysis of System-Wide Investment in the National Airspace System: A Portfolio Analytical Framework and an Example

In this paper, the authors review the FAA s current program investments and lay out a preliminary analytical framework to undertake projects that may address some of the noted deficiencies. By drawing upon the well developed theories from corporate finance, an analytical framework is offered that can be used for choosing FAA s investments taking into account risk, expected returns and inherent dependencies across NAS programs. The framework can be expanded into taking multiple assets and realistic values for parameters in drawing an efficient risk-return frontier for the entire FAA investment programs

Analysis of caesarean section in a tertiary care hospital, Assam, India

Background: One of the commonest surgery performed worldwide is caesarean Section (CS). The World Health Organization (WHO) has identified an ideal caesarean section (CS) rate for a nation of around 10-15%. In recent times the proportion of delivery conducted by caesarean section has increased.Methods: This is a retrospective study of all the caesarean deliveries performed between 1st January 2010 to 31st December 2018 in the Department of Obstetrics and Gynaecology in Silchar Medical College. The caesarean rate was calculated as: (total number of caesarean deliveries/ total number of deliveries) × 100. The indications for CS included foetal distress, malpresentation, previous caesarean section, multiple gestation, failed induction, failed progression, cephalopelvic disproportion, maternal indications, obstetric indication and foetal indications.Results: During the study period a total of 75685 patients delivered. 25805 patients had undergone CS with the CS rate being around 34.1%. Majority of the CS (75.6%) were performed as emergency procedure. Maximum number of patients were between 21-30 years (73.24%) and 54.47% were primipara. Majority of the patients (68.37%) belonged to the rural areas. Foetal distress (32.8%) was the commonest indication followed by post caesarean pregnancy (26.76%).Conclusions: The rate of caesarean section is increasing with time. As primary caesarean section usually determines the lady’s future obstetric course, it is of prime importance to give effort for safe reduction of caesarean. Individualization of the indication and careful evaluation, following standardized guidelines and practice of evidenced-based obstetrics followed by audits in the institution, can help us limit the caesarean rates

TeV neutrinos and gamma rays from pulsars

Recent studies suggest that pulsars could be strong sources of TeV muon neutrinos provided positive ions are accelerated by pulsar polar caps to PeV energies. In such a situation muon neutrinos are produced through the delta resonance in interactions of pulsar accelerated ions with its thermal radiation field. High energy gamma rays also should be produced simultaneously in pulsar environment as both charged and neutral pions are generated in the interactions of energetic hadrons with the ambient photon fields. Here we estimate TeV gamma ray flux at Earth from few nearby young pulsars. When compared with the observations we find that proper consideration of the effect of polar cap geometry in flux calculation is important. Incorporating such an effect we obtain the (revised) event rates at Earth due to few potential nearby pulsars. The results suggest that pulsars are unlikely to be detected by the upcoming neutrino telescopes. We also estimate TeV gamma ray and neutrino fluxes from pulsar nebulae for the adopted model of particle acceleration.Comment: Six pages, accepted in MNRA

Compatibility of Einstein minimally coupled self interacting scalar field theory with the solar system tests of gravity

We examine the compatibility of the Einstein minimally coupled self-interacting scalar field theory with the local tests of gravity. We find that apart from the trivial case of the Schwarzschild-de Sitter solution with constant scalar field the theory does not admit any other static solution, which is consistent with the solar system tests of gravity.Comment: 6 pages, a part of the earlier version removed, final version accepeted by CQ

PIC: Protein Interactions Calculator

Interactions within a protein structure and interactions between proteins in an assembly are essential considerations in understanding molecular basis of stability and functions of proteins and their complexes. There are several weak and strong interactions that render stability to a protein structure or an assembly. Protein Interactions Calculator (PIC) is a server which, given the coordinate set of 3D structure of a protein or an assembly, computes various interactions such as disulphide bonds, interactions between hydrophobic residues, ionic interactions, hydrogen bonds, aromatic–aromatic interactions, aromatic–sulphur interactions and cation–π interactions within a protein or between proteins in a complex. Interactions are calculated on the basis of standard, published criteria. The identified interactions between residues can be visualized using a RasMol and Jmol interface. The advantage with PIC server is the easy availability of inter-residue interaction calculations in a single site. It also determines the accessible surface area and residue-depth, which is the distance of a residue from the surface of the protein. User can also recognize specific kind of interactions, such as apolar–apolar residue interactions or ionic interactions, that are formed between buried or exposed residues or near the surface or deep inside