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951.
In this paper, based on the verifiable pair and identity-based threshold cryptography, a novel identity-based (ID-based) threshold decryption scheme (IDTDS) is proposed, which is provably secure against adaptive chosen ciphertext attack under the computational bilinear Diffie-Hellman (CBDH) problem assumption in the random oracle. The pubic checkability of ciphertext in the IDTDS is given by simply creating a signed ElGamal encryption instead of a noninteractive zero-knowledge proof. Furthermore, we introduce a modified verifiable pairing to ensure all decryption shares are consistent. Our scheme is more efficient in verification than the schemes considered previously.  相似文献   
952.
The interaction between acetylgliotoxin and human serum albumin (HSA) has been studied by spectroscopic method. Acetylgliotoxin quenches the intrinsic fluorescence of HSA in a static quenching procedure. The binding of acetylgliotoxin to HSA causes a slight conformational change of HSA. The binding constants at different temperatures as well as enthalpy change and entropy change, are calculated according to relevant fluorescent data and Van’t Hoff equation. The hydrogen bond is a predominant intermolecular force for stabilizing the complex, which is in conformity with the results of molecular modeling study.  相似文献   
953.
954.
For the problem of track correlation failure under the influence of sensor system deviation in wireless sensor networks, a new track correlation method which is based on relative positional relation chart matching is proposed. This method approximately simulates the track correlation determination process using artificial data, and integrally matches the relative position relation between multiple targets in the common measuring space of various sensors in order to fulfill the purpose of multi-target track correlation. The simulation results show that this method has high correlation accuracy and robustness.  相似文献   
955.
A slight halophilic heterotrophic nitrobacteria named gs1 was separated from the matured activated sludge. According to the morphological observation,physiological biochemical tests and sequence analysis of the 16S rDNA,strain gs1 was identified to be as Pseudomonas sp. Sodium acetate and ammonium chloride were used as carbon and nitrogen sources,respectively,to investi-gate the characteristics of the bacterium. When cultured for 24 h under aerobic conditions,with the removal rates of the NH4+-N and COD being 82.2% and 74.73%,respectively,strain gs1 will have a nitrification function of producing NO2--N. When cultured for 24 h under aerobic conditions in nitrite medium,the removal rate of the NO2--N became 100%,and when cultured for 24 h under aerobic conditions in nitrate medium,the removal rate of the NO3--N became 97%. The result shows that this strain functions for either nitrification or denitrification,i.e.,it can complete the full process of biological deoxidation.  相似文献   
956.
A method of sequence-based typing (SBT) has been adopted to assort types of exons 2 and 3, which have the most polymorphism, of HLA-B locus of the Tujia nation group in Hubei province. The correlation among the HLA-B alleles, human papillomavirus (HPV) infection and cervical cancer risk has also been investigated. Under the condition of resident location and age, race unified, 100 specimens of cancer patients were sampled as a case group, of which 86 were HPV positive and were screened for HLA-B alleles; while 187 specimens were taken from healthy people, of which 92 were HPV negative as a control group. The result shows that by comparing the above mentioned 86 HPV positive cervical cancer group and 92 HPV negative normal group, it was concluded that HLA-B*6701 was only found in the cervical cancer group (p < 0.034), which shows that HLA-B*6701 can be used as an important candidate biological marking gene for generation of cervical cancer in Wufeng county of Hubei province.  相似文献   
957.
We study the functions with low differential uniformity, and concentrates mainly on the properties of perfect nonlinear (PN) functions, including the properties of the derivative of the components of those functions. Some sufficient and necessary conditions have been explored to judge when a function is a PN function. These conditions may be useful in constructing new PN functions. We also construct some functions with differential 4-uniformity that have rarely been studied in the literature. Some of the constructed functions with differential 4-uniformity have high nonlinearity as well. Finally, a class of functions with differential 4-uniformity which are not extended affine equivalent to any power functions are constructed.  相似文献   
958.
A Kleene-Stone algebra is a bounded distributive lattice with two unary operations that make it a Kleene and a Stone algebra. In this paper, we study the properties of the prime ideals in a Kleene-Stone algebra and characterize the class of Kleene-Stone algebras that are congruence permutable by means of the dual space of a Kleene-Stone algebra and then show that a finite Kleene-Stone algebra is congruence permutable if and only if it is isomorphic to a direct product of finitely many simple algebras.  相似文献   
959.
So far, most of the proposed group key exchange (GKE) protocols do not consider the attack when the adversary reveals the parties’ephemeral private keys without their long-term private keys, so these GKE protocols are insecure on this attack. In this paper, for resisting above attack, we propose a dynamic authenticated group key exchange (AGKE) protocol in the ID-based setting. Different from previous ID-based protocols, our protocol does not utilize bilinear pairings, which makes it more efficient. At last, we analyze the security of the protocol in the eCK (enhanced Canetti-Krawczyk) security model.  相似文献   
960.
<正> This paper formulates and analyzes a line search method for general nonlinear equalityconstrained optimization based on filter methods for step acceptance and secant methods for searchdirection.The feature of the new algorithm is that the secant algorithm is used to produce a searchdirection,a backtracking line search procedure is used to generate step size,some filtered rules areused to determine step acceptance,second order correction technique is used to reduce infeasibility andovercome the Maratos effect.Global convergence properties of this method are analyzed:under mildassumptions it is showed that every limit point of the sequence of iterates generated by the algorithmis feasible,and that there exists at least one limit point that is a stationary point for the problem.Moreover,it is also established that the Maratos effect can be overcome in our new approach by addingsecond order correction steps so that fast local superlinear convergence to a second order sufficient localsolution is achieved.Finally,the results of numerical experiments are reported to show the effectivenessof the line search filter secant method.  相似文献   
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