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991.
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
992.
The urbanization process is a trend occurring inevitably in the historical development. This paper reviews the progress of the urbanization in Guangzhou and focuses on the change of water quality in the Guangzhou reach of the Pearl River. 8 kinds of main pollutant parameters were collected from 9 important sections in the Guangzhou reach of the Pearl River from 1986 to 2000 and the water quality change was analyzed per time and space. The study concludes that the surface water quality of Guangzhou reflects ... 相似文献
993.
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
994.
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
995.
The Sutong Bridge, a cable-stayed located in the southeast coastal area of China, is vulnerable to the Pacific typhoons. From the data measured by two 3D ultrasonic anemometers at the height of 76 m and 306 m, the wind characteristics (including 10-minute mean wind speed and direction, turbulence intensity and gust factor, power spectral density and integral scale of turbulence) of Typhoon Kalmaegi are analyzed The comparison of 10-minute mean wind velocity from the two anemometers validates the reliability... 相似文献
996.
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
997.
We considered the following semiparametric regres-sion model yi = X iT β+ s ( t i ) + ei (i =1,2,,n). First,the general-ized ridge estimators of both parameters and non-parameters are given without a restrained design matrix. Second,the generalized ridge estimator will be compared with the penalized least squares estimator under a mean squares error,and some conditions in which the former excels the latter are given. Finally,the validity and feasibility of the method is illustrated by a simulation example. 相似文献
998.
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
999.
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
1000.
<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