Analysis of Key Management Schemes for Secure Group Communication and Their Classification

Secure Group Communication is very critical for applications like board-meetings, group discussions and teleconferencing. Managing a set of secure group keys and group dynamics are the fundamental building blocks for secure group communication systems. Several group key management techniques have been proposed so far by many researchers. Some schemes are information theoretic and some are complexity theoretic in nature. Users in the secure group may negotiate with each other to derive a common group key or may compute the group key on their own. Some schemes involve a trusted Key Distribution Center (KDC), which generates and distributes initial pieces of information, whereas in other schemes users themselves select their private information. Storage at each user and communication cost among members of the group vary from scheme to scheme. Here, in this paper we discuss some of the key management schemes proposed earlier based on the considerations mentioned above. We also analyze the schemes with respect to storage, communication and computation costs

Analysis of Key Management Schemes for Secure Group Communication and Their Classification

Secure Group Communication is very critical for applications like board-meetings, group discussions and teleconferencing. Managing a set of secure group keys and group dynamics are the fundamental building blocks for secure group communication systems. Several group key management techniques have been proposed so far by many researchers. Some schemes are information theoretic and some are complexity theoretic in nature. Users in the secure group may negotiate with each other to derive a common group key or may compute the group key on their own. Some schemes involve a trusted Key Distribution Center (KDC), which generates and distributes initial pieces of information, whereas in other schemes users themselves select their private information. Storage at each user and communication cost among members of the group vary from scheme to scheme. Here, in this paper we discuss some of the key management schemes proposed earlier based on the considerations mentioned above. We also analyze the schemes with respect to storage, communication and computation costs

Design and Optimization of Bicycle Frame for the Cyclist's Comfort

Bicycle plays an inherent role in our life. Bicycle riding is a globally popular sport and an economic transportation. The performance of frame is depends on the weight of the bicycle and frame design. Optimization of weight and structure of the bicycle frame is the best scope of optimizing the overall performance of the bicycle. When the rider ridding bicycle on rough surface, the induced vibrations will cause the fatigue of its rider and the fracture of its frame structure. This paper deals with the study of the structural design, modal analysis and optimization of bicycle frame by using composite material with help of FEA. Firstly structural analysis, numerical results obtained by applying dynamic loading condition. Secondly, the Modal analysis is used to identify modes of bicycle frame to calculate natural frequencies and mode shapes by using Finite Element Analysis. Finally, the analyzed frames are then optimized to reduce weight without affecting their capacity to be resistant to mechanical stresses

Tailoring of Energy Band Gap inGraphene-like System by Fluorination

Fluorinated grapheme has a two-dimensional layer structure with a wide band gap. In the present study, Fluoro Graphene (FG) is obtained from Graphene Oxide (GO) through a deoxyfluorination reaction with the aid of Diethylaminosulphurtrifluoride (DAST). The FT-IR exhibited a peak at 1216 cm-1 and the shoulder at 1312 cm-1 were ascribed to the stretching vibration of covalent C–F bonds and C–F2 bonds, respectively. Surface morphology revealed a leafy structure in GO and a rocky structure in FG. The EDS analysis confirmed the fluorination of the graphitic structure. The TEM analysis confirmed the formation of a mixed structure of graphene and carbon dots. The results of structural, morphological and electrical properties of both graphene oxide and fluorographene show the possibility of using these samples as electronic/electrochemical devices in future

FORMULATION AND EVALUATION OF GLIPIZIDE MICROEMULSION

Objective: The aim of the present study was to formulate a microemulsion for the oral delivery of Glipizide.Methods: Microemulsion systems composed of oleic acid, isopropyl myristate as oils; tween 80, span 20 and cremophor EL as surfactants; propylene glycol, isopropyl alcohol as cosurfactants were investigated as potential drug delivery vehicle for delivery for glipizide. Pseudo-ternary phase diagram of the investigated system at constant surfactant concentration and varying oil/water or oil/cosurfactant ratios was constructed at room temperature by titration method. This allowed studying structural inversion from oil-in-water to water-in–oil microemulsion. Furthermore, electrical conductivity, in vitro dissolution studies, pH, centrifugation, % transmittance, viscosity, particle size, polydispersity index, zeta potential, DSC and accelerated stability studies were conducted.Results: The results of electrical conductivity clearly indicated the structural inversion. Based on these values oil/water microemulsions were selected. The plain drug has shown only 40% of dissolution, while the drug from all the o/w microemulsions has shown>90% dissolution. Based on in vitro release studies f3, f12, f22 formulations were chosen. Particle size values of f3, f12, f22 formulations are 202.4 nm, 83.3 nm, 315.3 nm respectively. Viscosity results showed that the formulations follow the Newtonian flow.Conclusion: The 3 formulations f3, f12 and f22 were successful in increasing the dissolution of glipizide in GIT and capable of sustaining the release of the drug for 8 h. From the viscosity, particle size, polydispersity index values, f12 was considered as the optimized formulation. Further, centrifugation, zeta potential and accelerated stability studies also indicated that the formulations were stable. DSC studies revealed no drug-excipient interaction in the optimized formulation. Owing to the above results microemulsion can be thus considered as a suitable oral delivery system for glipizide.Â

Newspaper – an ICT Instrument to Facilitate Teaching-Learning Process

Proficiency in English language can be a driving force for a person to excel in his/her careers, either at national or international level. Recent statistics indicate that the readership of newspapers, more particularly, that of English newspapers has increased to an appreciable level, and it is this strand which needs to be exploited. In spite of the digital revolution, the sheen of print media has not faded. Edgar Dale’s ‘Cone of Experience’ explicitly states that decoding the textual symbols is at the top of the cone, and thus by reading newspapers, one not only strengthens LSRW skills but also enhances higher order skills – problem solving, research, editorial, autonomous learning competence, and critical analysis. In the teaching- learning process, blended learning and flipped classroom are some methods which can be employed in the process of using newspaper as a learning device. Through activities like description, analysis, and synthesis; comparison and contrast; process description - learners will be able to upgrade their cognitive skills

The Radiative Transport of Dust in Primordial Galaxies and Second-Generation Star Formation

We investigate the radiativetransport of dust inprimordial galaxies in thepresence of the UVradiation field from thefirst metal-free stars. Wefind that dust createdin the first supernova(SN) explosions can bedriven through the interiorof the SN remnantto accumulate in theSN shells, where second-generationstars may form fromcompressed cooling gas. Thisscenario requires metal-free starsto form continuously overtimescales of up to10 Myr, consistent withrecent estimates. Silicate andgraphite grains, as wellas iron-bearing magnetites, aretransported to the shellsfor reasonable parameter assumptions,but their relative yieldsfrom primordial SNe isan important factor inthe resulting abundance ratios.We compare the resultsof segregated grain transportwith the current nucleosyntheticdata on extremely metal-poorGalactic halo stars. Fossilsignatures of this processmay already have beendetected in those iron-poorstars with enhanced carbonand silicate elements suchas magnesium, silicon andoxygen. We discuss theimplications of our resultsfor the transition fromfirst- to second-generation starformation in primordial galaxies,and the role playedby the radiative transportof dust in thisprocess