Advanced Materials Research Vols. 532-533

Abstract: Pseudoknots are complicated and stable RNA structure. Based on the idea of iteratively forming stable stems, and the character that the stems in RNA molecules are relatively stable, an algorithm is presented to predict RNA secondary structure including pseudoknots, it is an improvement from the previously used algorithm ,the algorithm takes O(n³) time and O(n²) sapce , in predicting accuracy, it outperforms other known algorithm of RNA secondary structure prediction, its performance is tested with the RNA sub-sequences in PseudoBase. The experimental results indicate that the algorithm has good specificity and sensitivity.

Abstract: Multicast routing technology of wireless sensor network is a method of transferring special data to a group of clients selectively; therefore, quality of the services is the key to evaluate the method. Ant colony algorithm is a bionic optimization algorithm. Improved QoS Multicast Routing Algorithm is proposed based on energy constraint and based on ant colony algorithm, it takes into account the energy cost routing, making the nodes to establish of minimum cost path under the condition of energy constraint. The results show that this algorithm can obtain better energy balance, improve the network services of the time. This algorithm applies to energy-sensitive multicast applications in wireless sensor networks.

Abstract: A variety of video watermarking algorithm is not rare. But the connection of watermarking algorithm and video feature is a completely new field. This algorithm attempts to generate the watermarking image based the number of video’s key frames. All the key frame numbers are converts to a binary matrix after data transformation, at last the binary image is produced. According to those steps, the watermarking image reflects the video’s features, so it is easy to resist the watermark copy attack.

Abstract: A novel approach to the schedulability analysis is presented in this paper for timing constraint Petri nets, which have wide applications in the workflow management, software engineering, reliability engineering, and so on. The analysis can be conducted in two phases: finding firing sequences and timing constraint analysis, among which the first one is to find the transition sequences that transform the initial marking to a certain marking by using incidence matrix in the underlying Petri net, and the second one is to verify whether the reachable marking found in the first step is reachable with the timing constraints. The proposed method is able to pinpoint out non-schedulable transitions and adjust the timing constraints to make all the transitions schedulable within complex task sequences, while meeting the needs of the managers to schedule the tasks.

Abstract: The paper mainly studies the algorithm of identifying the object of the web image, using the visual feature of the object in the image and the knowledge base, based on the image analysis and the extraction of the text in the web image.

Abstract: A novel parameter estimation method for unknown static parameters of the state space model using particle filtering (PF) has proposed in this paper. Traditional methods enlarge state vector by treating the unknown parameter θ as a part of state vector (x_k,θ) . But this may cause the degeneration of θ, when some estimates become too small to continue as a result of the non-dynamic character of parameters if θ at time k is only determined by time k-1. Compared to traditional methods, this novel method assumes that the posterior distribution of θ is given by previous observation and state vectors, z_1:k and x_1:k. Obtain statistics at time k by using the integration of z_1:k and x_1:k, and solve parameter estimation problem by updating θ recursively. Good results are obtained when this method is used in different models.

Abstract: The disadvantages of Apriori algorithm are firstly discussed. Then, a new measure of cosine similarity is proposed and treated as an interest threshold. Furthermore, an improved Apriori algorithm called Sim-Apriori is proposed based on similarity. It cannot only accurately find the relations between different products in transactions databases and reduce the useless rules but also handle the negative rules. Experiments have been carried out to verify the effectiveness of the algorithm. A Sim-Apriori system is developed by ASP.NET and SQL SERVER in B/S mode. The result shows that the algorithm is effective at discovering the association rules in sales management related ERP.

Abstract: Due to the existence of large numbers of local and global optima of super-high dimension complex functions, general Particle Swarm Optimizer (PSO) methods are slow speed on convergence and easy to be trapped in local optima. In this paper, an Adaptive Particle Swarm Optimizer(APSO) is proposed, which employ an adaptive inertia factor and dynamic changes strategy of search space and velocity in each cycle to plan large-scale space global search and refined local search as a whole according to the fitness change of swarm in optimization process of the functions, and to quicken convergence speed, avoid premature problem, economize computational expenses, and obtain global optimum. We test the proposed algorithm and compare it with other published methods on several super-high dimension complex functions, the experimental results demonstrate that this revised algorithm can rapidly converge at high quality solutions.

Abstract: A web service composition method based on the adaptive genetic operator was proposed to deal with the issues of the lack of adaptability and the easy-premature phenomena in web services composition genetic algorithm. Adaptive crossover and mutation operator were designed according to the individual adaptability and evolution stage for enlarging local search range and increasing convergent speed. Moreover, use for reference the idea of taboo table in taboo search algorithm, we can inhibit the algorithm from converging to false optimal solution untimely; meanwhile, an evolution strategy was adopted to prevent the loss of composite service with high fitness value. The experimental result shows that better composite services can be gotten through the improved algorithm; moreover the convergence speed has also been improved.

Abstract: Discrete Fourier Transform (DFT) is widely used in spectrum analysis. All Phase Fast Fourier Transform (APFFT) is proposed to improve FFT. It has merits such as phase invariance and small spectral leakage. But APFFT is a concrete algorithm. There are no parameters to adjust the result. The paper researches APFFT by changing the length of the overlapping data segments of APFFT. This change gives APFFT some new characteristic and some meaningful results are got.