Key-management scheme for wireless sensor networks based on merging blocks of symmetric design

Wireless sensor networks as the key infrastructure of the new networking paradigm are vulnerable against different kinds of attacks. Therefore, ensuring a secure communication between the sensor nodes is important. One of the most critical issues in this regard is the key distribution mechanism. Due to the random deployment of the sensors in the target area, key pre-distribution is a promising approach, in which a list of keys, so-called key-ring, is pre-distributed to each sensor node before deployment. To establish a secure communication, two nodes must share a common key from their key-rings. In this paper, we consider a hybrid key pre-distribution approach based on the symmetric design. We propose a new scheme, which is a modification of the hybrid symmetric design in order to improve the connectivity and resilience. Considering the trade-off between resilience and connectivity, we introduce a new parameter based on the application requirement. The experimental results and analytical analysis approve the efficiency of our proposed approach and introduced parameter.     

Synthesis,spectroscopic characterization,crystal structure determination and DFT calculations of [Au(Me<Subscript>2</Subscript>phen)Br<Subscript>2</Subscript>][AuBr<Subscript>2</Subscript>]

New mixed valence gold(III/I) salt containing two complexes [Au(Me₂phen)Br₂][AuBr₂] (1) was prepared from the reaction of AuBr₃ and 5,6-dimethyl-1,10-phenanthroline (Me₂phen) in a mixture of methanol and acetonitrile. Suitable crystals of 1 for X-ray diffraction measurement were obtained by slow evaporation of the resulted red solution at room temperature. This complex was characterized by spectral methods (IR, UV–Vis and ¹H NMR), elemental analysis and single-crystal X-ray diffraction. The X-ray structural analysis indicated that the asymmetric unit of 1 contains one [Au(Me₂phen)Br₂]⁺ cation and two half anions of [AuBr₂]^ˉ. Furthermore, the packing diagram of this complex, 3-D structure stabilized by intermolecular Au…Br and Au…π interactions and intermolecular C–H···Br hydrogen bonds. The experimental investigations on complex have been accompanied computationally by the density functional theory (DFT) and time-dependent DFT calculations. The nature of the Au–N bonds was investigated using quantum theory of atoms in molecules. Moreover, natural bond orbital analysis carried out to obtain hyper-conjugative interactions and electron delocalization on the complex.     

Process-Dependent Solute Transport in Porous Media

Transport in Porous Media - Solute transport under single-phase flow conditions in porous micromodels was studied using high-resolution optical imaging. Experiments examined loading (injection of...     

Property (RD) for Hecke Pairs

As the first step towards developing noncommutative geometry over Hecke C ^∗-algebras, we study property (RD) (Rapid Decay) for Hecke pairs. When the subgroup H in a Hecke pair (G, H) is finite, we show that the Hecke pair (G, H) has (RD) if and only if G has (RD). This provides us with a family of examples of Hecke pairs with property (RD). We also adapt Paul Jolissant’s works in Jolissaint (J K-Theory 2:723–735, 1989; Trans Amer Math Soc 317(1):167–196, 1990) to the setting of Hecke C ^∗-algebras and show that when a Hecke pair (G, H) has property (RD), the algebra of rapidly decreasing functions on the set of double cosets is closed under holomorphic functional calculus of the associated (reduced) Hecke C ^∗-algebra. Hence they have the same K ₀-groups.     

Assessment of WENO schemes for multi‐dimensional Euler equations using GPU

This paper presents a detailed study on the implementation of Weighted Essentially Non‐Oscillatory (WENO) schemes on GPU. GPU implementation of up to ninth‐order accurate WENO schemes for the multi‐dimensional Euler equations of gas dynamics is presented. The implementation detail is discussed in the paper. The computational times of different schemes are obtained and the speedups are reported for different number of grid points. Furthermore, the execution times for the main kernels of the code are given and compared with each other. The numerical experiments show the speedups for the WENO schemes are very promising especially for fine grids. Copyright © 2014 John Wiley & Sons, Ltd.     

Study of in situ generation of carbocationic system from trityl chloride (Ph3CCl) which efficiently catalyzed cross-aldol condensation reaction

Organocatalyst trityl chloride (Ph₃CCl), by in situ formation of trityl carbocation with inherent instability, efficiently promotes the cross-aldol condensation reaction between cycloalkanones and arylaldehydes in solvent-free and homogeneous media to afford α,α′-bis(arylidene)cycloalkanones in high yields. Moreover, an attractive and plausible mechanism based on observations and the literature is proposed for the reaction.