Certificateless cryptography eliminates the key escrow problem in identity-based cryptography. Hierarchical cryptography exploits a practical security model to mirror the organizational hierarchy in the real world. In...
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Certificateless cryptography eliminates the key escrow problem in identity-based cryptography. Hierarchical cryptography exploits a practical security model to mirror the organizational hierarchy in the real world. In this paper, to incorporate the advantages of both types of cryptosystems, we instantiate hierarchical certificate less cryptography by formalizing the notion of hierarchical certificate less signatures. Furthermore, we propose an HCLS scheme which, under the hardness of the computational Diffie-Hellman (CDH) problem, is proven to be existentially unforgeable against adaptive chosen-message attacks in the random oracle model. As to efficiency, our scheme has constant complexity, regardless of the depth of the hierarchy. Hence, the proposal is secure and scalable for practical applications.
This paper considers the problem of constructing data aggregation trees in wireless sensor networks (WSNs)for a group of sensor nodes to send collected information to a single sink *** data aggregation tree contains t...
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This paper considers the problem of constructing data aggregation trees in wireless sensor networks (WSNs)for a group of sensor nodes to send collected information to a single sink *** data aggregation tree contains the sink node,all the source nodes,and some other non-source *** goal of constructing such a data aggregation tree is to minimize the number of non-source nodes to be included in the tree so as to save *** prove that the data aggregation tree problem is NP-hard and then propose an approximation algorithm with a performance ratio of four and a greedy *** also give a distributed version of the approximation *** simulations are performed to study the performance of the proposed *** results show that the proposed algorithms can find a tree of a good approximation to the optimal tree and has a high degree of scalability.
We present a scheme to realize a large cross-phase-modulation between two slow optical pulses by using the atomic configurations of coupled double dark resonances. In this scheme slow group velocities for these optica...
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We present a scheme to realize a large cross-phase-modulation between two slow optical pulses by using the atomic configurations of coupled double dark resonances. In this scheme slow group velocities for these optical pulses can be automatically equalized in terms of the inherent symmetric atomic configuration, and the various absorptions can be overcome by using three-photon hyper-Raman amplification. Additionally, the switching between cross-type nonlinear amplification and absorption could be realized by just changing the sign of the difference between two pump detunings. This is useful for the implementations of all-optical switches. The linearity and cross nonlinearity in the Doppler-broadened medium with different laser propagating configurations have also been investigated.
Hypertension,among diabetes,obesity and others,is one of the common human diseases that is genetically expressed as complex traits to which genetic,environmental,and demographic factors contribute *** the underlying g...
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Hypertension,among diabetes,obesity and others,is one of the common human diseases that is genetically expressed as complex traits to which genetic,environmental,and demographic factors contribute *** the underlying genes and examining their interactions, a crucial step in understanding the molecular pathogenesis of complex diseases,is both a statistical and a computational challenge,stressing the need for novel strategies to move this process *** this paper we propose a new method to study the association of multiple gene interactions for complex *** method is carried out by two ***,we sequentially select additionally associated SNP loci combinations by minimizing the p-value of a test based on an information measure,measure of information ***,this approach is called MID ***,the significance of the selected associated loci combinations is assessed by an x *** MID method is model-free and nonparametric,it is easy to compute and *** capability of the MID method is confirmed by applying it to investigate the multiple gene interactions on risk of hypertension in northern Han Chinese,where thirty-three SNP loci with three-genotype in eleven candidate genes are *** results are consistent with those of Gu et al(2006).Additionally,we get some other new *** indicates that our idea is indeed feasible and useful in practice.
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