Yunchang Zhang

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The P2P system is an anonymous and dynamic system, which offers enormous opportunities, and also presents potential threats and risks. In order to restrain malicious behaviors in P2P system, previous studies try to establish efficient trust models on P2P system. However, most of the trust models use a single trust metric, which can not reflect the practical(More)
Reputation-based trust management is an effective method to improve network security in P2P networks. In this paper, we present a trust evaluation model based on parameterestimation algorithms to enhance the accuracy of trust evaluation in unstructured P2P networks. Trust evaluation includes direct and second-hand trust information. It estimates and updates(More)
Neural networks with good nonlinear mapping abilities can be applied to build simulation model of helicopter. But they have some difficulties such as hardness of selecting network structure, slow convergence speed, local minimum, and over-fitting. To avoid above problems, a method for building simulation model of helicopter based on Wavelet Support Vector(More)
As a system identification method, neural network can be applied to build the simulation model of a helicopter. But it has some difficulties such as the hardness of selecting network structure, slow convergence speed, local minimum, and generalization ability question. To avoid the question above, the support vector machine (SVM) method is introduced to the(More)
Flame furnace atomic absorption spectrometry (FF-AAS) is a newly developed flame atomic absorption spectrometric technique based on arranging a flame furnace onto the top of the flame burner head. In this fundamental investigation, 25 elements were carefully tested by using either thermospray FF-AAS or tungsten coil electrothermal vaporization FF-AAS, of(More)
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