Applied Mechanics and Materials Vols. 530-531

Abstract: MCEM algorithm produces based on the evolution of the EM algorithm. According to the MCEM algorithm theory, the iterative formula of parameter estimation of Rayleigh was derived based on MCEM algorithm, meanwhile the computer simulation algorithm was designed. Computer simulation shows that , in the case of the small sample, parameter estimation of MCEM algorithm is more stable and precise than MLE algorithm.

Abstract: This paper study ordinary linear regression and ridge regression, ridge regression includes ordinary ridge regression (ORR) and generalized ridge regression (GRR). Comparison between these methods are made by an example, the results show that ridge regression has smaller standard deviation and MSE than OLS, and among all the methods, GRR is better than others.

Abstract: This paper is to study the estimation of stochastic volatility model with leverage effect using Bayesian approach and Markov Chain Monte Carlo (MCMC) simulation technique. The data used is China's Shenzheng stock index. Estimations of model parameters are achieved by using MCMC technique in Openbugs Software, results show that there is leverage effect in Shenzheng stock series, convergence diagnostics suggest that parameters of the model are convergent.

Abstract: In the paper, by the symmetrical Mountain-Pass lemma in critical point theory, the existence of infinitely anti-and odd periodic solutions with a fixed period is obtained for a class of symmetric superquadratic non-autonomous Hamiltonian systems.

Abstract: In this letter, we apply the homotopy analysis method (HAM) to obtain analytical solution of the fractional equation where the fractional derivatives are Caputo sense. The example is given to show the efficiency of the method.

Abstract: In this article, the semilattice decomposition of r-ample semigroups with left central idempotents is given. By using this decomposition, we show that a semigroup is a r-ample semigroup with left central idempotents if and only if it is a strong semilattice of , where is a monoid and is a right zero band. As a corollary, the characterization theorem of Clifford semigroups is also extended from a strong semilattice of groups to a strong semilattice of right groups. These theories are the basis that the structure theorem of r-ample semigroups with left central idempotents can be established.

Abstract: Price forecasting based on training step is discussed in this paper. The purpose of forecasting is obtaining suitable commodity price forecasting model. This experiment uses a whole year price for ten type's mobile phone .The price data is extracted from http://www.jd.com/. The whole year data is used as the original data to improve Least Squares Support Vector Machine (LS-SVM) model based on the training step. By researching this forecasting method, the experiments are carried out under different training steps, different types cell phones depending on the accuracy rata. With the growth of the training step, the precision of the LS-SVM model cuts down obviously. The research can help consumers obtain the better purchase decision-making when they buy cell phones, provide cell-phone distributors with certain reference.

Abstract: In this paper, we present a stepwise genetic programming algorithm to perform regression on a large number of noisy data, the purpose of which is to find a mathematical model for samples. To obtain an accurate statistical model of noisy sample points, discrete cosine transform was inserted into a standard GP algorithm. The energy-compaction property of DCT makes it very suitable for accelerating the implement of the standard GP algorithm and dealing with the noisy data samples. We tested the proposed algorithm with benchmark instances and compared it with several popular other algorithms. The experimental results have shown that the proposed algorithm is a powerful tool in finding optimal solutions.

Abstract: Virtual systems are usually attacked due to the vulnerabilities in the hypervisor. The hypervisor cannot solve this because its code size is too big to implement totally right. This paper proposed a new hardware-software architecture based on hardware isolation, which adds a new component in CPU to provide hard-level isolation. Even when the malicious code gets the highest software privilege, it cannot break into another domain from current domain. This paper also gives the implementation of the booting, memory isolation, scheduling, interrupt handling and inter-domain communication.

Abstract: The portable terminal such as iPad, WIFI phone has limited computing power and transmission bandwidth compared with specialized computer, which is difficult to implement key cryptography algorithm with large amount of calculation question. This paper introduces a new EAP authentication method based on EAP-SAKE using hash function. Analysis result shows that the method can provide mutual authentication and key negotiation between peers,and can resist replay attack and man-in-middle attack.It has less communication load and computing amount, so it is more suitable for protecting the information security to portable mobile terminal which has limited resource in WLAN.