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Full-Text Articles in Physical Sciences and Mathematics

New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan Jan 2012

New Constructions Of Osbe Schemes And Their Applications In Oblivious Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan

Faculty of Informatics - Papers (Archive)

Oblivious signature-based envelope (OSBE) schemes have demonstrated their potential applications in the protection of users privacy and rights. In an OSBE protocol, an encrypted message can only be decrypted by the receiver who holds a valid signature on a public message, while the sender (encrypter) does not know whether the receiver has the signature or not. Our major contributions in this work lie in the following aspects. We improve the notion of OSBE so that a valid credential holder cannot share his/her credential with other users (i. e., all-or-nothing non-transferability). We clarify the relationship between one-round OSBE and identity-based encryption …


Solitary Waves And Their Stability In Colloidal Media: Semi-Analytical Solutions, Timothy R. Marchant, N F. Smyth Jan 2012

Solitary Waves And Their Stability In Colloidal Media: Semi-Analytical Solutions, Timothy R. Marchant, N F. Smyth

Faculty of Informatics - Papers (Archive)

Spatial solitary waves in colloidal suspensions of spherical dielectric nanopartides are considered. The interaction of the nanoparticles is modelled as a hard-sphere gas, with the Carnahan-Starling formula used for the gas compressibility. Semi-analytical solutions, for both one and two spatial dimensions, arc derived using an averaged Lagrangian and suitable trial functions for the solitary waves. Power versus propagation constant curves and neutral stability curves are obtained for both cases, which illustrate that multiple solution branches occur for both the one and two dimensional geometries. For the one-dimensional case it is found that three solution branches (with a bistable regime) occur. …


A Unified Study Of Epidemic Routing Protocols And Their Enhancements, Zuyong Feng, Kwan-Wu Chin Jan 2012

A Unified Study Of Epidemic Routing Protocols And Their Enhancements, Zuyong Feng, Kwan-Wu Chin

Faculty of Informatics - Papers (Archive)

Epidemic protocols belong to a class of routing paradigm that have wide ranging applications in Delay Tolerant Networks (DTNs) due to their simplicity, low delays, and little to no reliance on special nodes. To this end, a comprehensive study of their performance will serve as an important guide to future protocol designers. Unfortunately, to date, there is no work that studies epidemic routing protocols using a common framework that evaluates their performance objectively using the same mobility model and parameters. To this end, we study four categories of epidemic routing protocols. Namely, P-Q epidemic, epidemic with Time-To-Live (TTL), epidemic with …


The Synthesis Of Lamellar Nano Mgb2 Grains With Nanoimpurities, Flux Pinning Centers And Their Significantly Improved Critical Current Density, Zongqing Ma, Yongchang Liu, Qi Cai Jan 2012

The Synthesis Of Lamellar Nano Mgb2 Grains With Nanoimpurities, Flux Pinning Centers And Their Significantly Improved Critical Current Density, Zongqing Ma, Yongchang Liu, Qi Cai

Australian Institute for Innovative Materials - Papers

MgB2 superconductors with unique microstructures were rapidly fabricated at low temperatures, and exhibited significantly improved critical current density (Jc). According to the microstructure observations, the prepared samples consisted of lamellar nano MgB2 grains with many embedded nanoimpurities (about 10 nm). The formation of these lamellar nano MgB2 grains is associated with the presence of a local Mg-Cu liquid at sintering temperatures as low as 575°C. The ball milling treatment of the original powders also plays a positive role in the growth of lamellar grains. Based on an analysis of the relationship between resistivity and temperature, the lamellar nano MgB2 grains …


Lime Muds And Their Genesis Off-Northwestern India During The Late Quaternary, V P. Rao, A Anil Kumar, S W A Naqvi, Allan R. Chivas, B Sekar, Pratima M. Kessarkar Jan 2012

Lime Muds And Their Genesis Off-Northwestern India During The Late Quaternary, V P. Rao, A Anil Kumar, S W A Naqvi, Allan R. Chivas, B Sekar, Pratima M. Kessarkar

Faculty of Science - Papers (Archive)

Two sediment types were found in five gravity cores collected from water depths between 56 m and 121 m along the northwestern continental margin of India: lime muds were abundant in the lower section while siliciclastic sediments dominated the upper section. Lime mud-dominated sediments in shelf cores contained 60%–75% carbonate, 0.3%–0.6% Sr and terrigenous minerals, whereas those at the shelf break were found to have >90% carbonate, 0.6%–0.8% Sr and traces of terrigenous minerals. Aragonite needles showing blunt edges, jointed needles and needles wrapped in smooth aragonite cement were found to be common. Stable (O and C) isotopes of lime …


Selective Reduction Of Hydroperoxyeicosatetraenoic Acids To Their Hydroxy Derivatives By Apolipoprotein D: Implications For Lipid Antioxidant Activity And Alzheimer's Disease, Surabhi Bhatia, Bianca Knoch, Jenny Wong, Woojin Scott Kim, Paul Else, Aaron J. Oakley, Brett Garner Jan 2012

Selective Reduction Of Hydroperoxyeicosatetraenoic Acids To Their Hydroxy Derivatives By Apolipoprotein D: Implications For Lipid Antioxidant Activity And Alzheimer's Disease, Surabhi Bhatia, Bianca Knoch, Jenny Wong, Woojin Scott Kim, Paul Else, Aaron J. Oakley, Brett Garner

Faculty of Science - Papers (Archive)

ApoD (apolipoprotein D) is up-regulated in AD (Alzheimer's disease) and upon oxidative stress. ApoD inhibits brain lipid peroxidation in vivo, but the mechanism is unknown. Specific methionine residues may inhibit lipid peroxidation by reducing radical-propagating L-OOHs (lipid hydroperoxides) to non-reactive hydroxides via a reaction that generates MetSO (methionine sulfoxide). Since apoD has three conserved methionine residues (Met49, Met93 and Met157), we generated recombinant proteins with either one or all methionine residues replaced by alanine and assessed their capacity to reduce HpETEs (hydroperoxyeicosatetraenoic acids) to their HETE (hydroxyeicosatetraenoic acid) derivatives. ApoD, apoDM49-A and apoDM157-A all catalysed the reduction of HpETEs to …


Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer Jan 2012

Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer

Australian Institute for Innovative Materials - Papers

Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900 degress C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/ PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst …