In order to solve the problems in the existing frequent pattern mining algorithms, such as complex tree building and low mining efficiency, a high-performance algorithm for mining frequent patterns was proposed, namely B-List Frequent Pattern Mining (BLFPM). A new data structure of Building list (B-list) was employed to represent frequent itemsets, and the frequent patterns were directly discovered by intersecting two B-lists without scanning the database. Aiming at the high time complexity of connecting two B-lists, a linear time complexity connection method was proposed to improve the time efficiency of BLFPM. Besides, set-enumeration search tree and an efficient pruning strategy were adopted to greatly reduce the search space and speed up the execution. Compared to N-list and Subsume-based algorithm for mining Frequent Itemsets (NSFI) and prepost algorithm, the time efficiency of BLFPM was improved by about 12% to 29%, and the space efficiency of BLFPM was improved by about 10% to 24%. The experimental results show that BLFPM has good performance for both sparse database and intensive database.

Chinese addresses on the Internet are always non-normalized, which cannot be used directly in location-based services. To solve the problem, an algorithm to extract administrative divisions from non-normalized Chinese addresses was proposed. Firstly, preprocessing "road" feature word grouping for original data; using administrative division dictionary and moving window maximum matching algorithm, extract all possible administrative region data sets from Chinese address. Then, using the Chinese administrative divisions between the elements of the hierarchical relationship between the characteristics, the administrative set conditional set operation rule was established and the acquired data set was aggregated. using the administrative division of matching, a set of administrative division set rules were established to calculate the credibility of the administrative division. Finally, the credibility of the maximum amount of information the most complete Chinese address of the administrative divisions were obtained. By using the extracted from the Internet about 250000 Chinese address data whether the use of "road" feature word packet processing and whether to carry on the credibility calculation process was verified for the availability of the algorithm, and with the current address matching technology for comparison, the accuracy rate of 93.51%.

In the decomposition of natural image containing texture, the edge information of structure image is easy to be regarded as the texture, which results in blurred edge of the structural image and inaccurate detected edge. An image decomposition and edge detection method was proposed based on wavelet transform of Partial Differential Equation (PDE). At first, wavelet transform threshold was used to extract texture information. Then the improved PDE image decomposition model was used to further decompose the image and extract the edge. The numerical experimental results show that this method improves the quality of image decomposition, makes the texture extraction through and the structure image piecewise smooth, and better protects the edge of the structure.

The identity-based ring signcryptions have both high efficiency of identity-based cryptosystem and signcryption technology and the ambiguity of ring signature. In the fair exchange protocol based on signcryption proposed by Luo, et al (Luo M, Zou C H, Hu J, 〖WTBX〗et al.〖WTBZ〗Signcryption-based fair exchange protocol. Journal of Communications, 2010, 31(8A): 146-150), the fairness and efficiency are not good enough. The new scheme introduced a more efficient identity-based ring signcryption and dealt with the decryption and the signature-and-identity binding separately. A new fair exchange protocol was proposed based on this new scheme. The analysis shows that this scheme overcomes the fairness defect of the original scheme and has a better efficiency, which makes it a good application in electronic payment and contract signing.