In order to effectively master protocol interactive behavior, a method to automatically build protocol interactive process based on message sequence chart was proposed. Firstly, according to the characteristics of the protocol interactive process, the dependency graph was defined to represent the partial order of events in message sequence, and the network flows were converted to dependency graphs. Secondly, the basic message sequences were used to describe protocol interactive behavior fragments, and the basic message sequences were mined by defining event maximum suffix. Finally, the maximum dependency graphs that were found out were connected and merged to build a message sequence chart. The experimental results show that the proposed method has a high accuracy and the built message sequence chart can visually represent the protocol interactive process.
For too many similar words and lots of irregular writing ways of the same words in the handwritten character recognition, a modified Affinity Propagation (AP) clustering algorithm was proposed to add to the recognition process. Clustering judging function Silhouette was combined with original AP algorithm in the proposed algorithm. Class number was updated by changing preference parameter adaptively through iterative process of AP algorithm. And then the optimal clustering result was obtained by assessing clustering quality of every iteration. The experiment of handwritten Chinese character recognition indicates that the recognition rate of recognition process added original AP algorithm is 1.52% higher than the rate of traditional recognition process. And the recognition rate of recognition process added modified AP algorithm is 1.28% higher than the rate of recognition process added original AP algorithm. The experimental results verify that it is effective to add clustering algorithm to the handwritten character recognition process. And compared with original AP algorithm, convergence and clustering quality of modified AP algorithm are also improved.
For the problem of minimizing the energy consumption under performance constraint of cloud center, an optimal power consumption allocation method among multiple heterogeneous servers was proposed. First, an optimal energy consumption mathematical model of cloud center was built. Second, a Minimizing Power Consumption (MPC) algorithm for calculating the minimum energy was developed by using Lagrange multiplier method to obtain the optimal solution of the model. Finally, the MPC algorithm was verified by plenty of numerical experiments and compared with the Equal-Power (EP) baseline method. The experimental results indicate that MPC algorithm can save approximately 30% energy than the EP baseline method under the same load and the same response time conditions, and the proportion of energy saving will increase with load increasing. The MPC algorithm can effectively avoid energy configuration overload and it will provide ideas and reference data for optimal resource allocation of cloud center.
Aiming at the problem of pulmonary small nodules was difficult to identify, a method using fuzzy C-means clustering algorithm to analyse the lung Region Of Interest (ROI) was presented. An improved Fuzzy C-Means clustering algorithm based on Plurality of Weight (PWFCM) was presented to enhance the accurate rate and speed of small nodules recognition. To improve the convergence, each sample and its features were weighted and a new membership constraint was introduced. The low sensitivity from the uneven ROI data was decreased by using a double clustering strategy. The experimental results tested on the real CT image data show that PWFCM algorithm can detect lung nodules with a higher sensitivity and lower false positive rate.
Since it is necessary to evaluate and analyze the service performance of cloud computing center to guarantee Quality of Service (QoS) and avoid violation of Service Layer Agreement (SLA), a approximated analysis model based on M/M/n/n+r queue theory was proposed for cloud computing center. By solving this model the probability distribution function of response time and other QoS indicators were acquired, meanwhile the relationship among the number of servers, size of queue buffers, response time, blocking probability and instance service probability were revealed and verified by simulation.The experimental results indicate that improving server service rate is better than increasing the number of servers for improving service performance.
In data layer, the course model and resource model were built based on Markov chain and vector space model, and the teacher model was built based on teachers' personal registration information and nodes of course model. In off-line layer, the content features of course model and resource model were extracted via Term Frequency-Inverse Document Frequency (TF-IDF) algorithm, and the course model and resource model of data layer were initialized and optimized. Then relations between any two resources or recourse and course were calculated using association rules mining and similarity measure, and intermediate recommendation results were given using teacher model and course model. A weighted hybrid recommendation algorithm was proposed to generate recommendation list in on-line layer. The proposed system has been successfully applied in a real education resources sharing platform which consists of 600 thousand teaching resources.