Abstract:With the success of VTK (visualization ToolKit) and ITK (insight segmentation and registration ToolKit), there are more attentions to the toolkit development issue in medical imaging community. This paper introduces MITK (medical imaging ToolKit), an integrated 3D medical image processing and analyzing toolkit. Its main purpose is to provide a consistent framework to combine the function of medical image segmentation, registration and visualization. The design goals, overall framework, and implementation of some key technologies are provided in details, and some application examples are also given to demonstrate the ability of MITK. We hope that MITK will become another available choice for the medical imaging community.

Abstract:This paper uses ensemble learning technique to improve clustering performance. Since the training data used in clustering lacks the expected output, the combination of component learner is more difficult than that under supervised learning. Through aligning different clustering results and selecting component learners with the help of mutual information weight, this paper proposes a Bagging-based selective clusterer ensemble algorithm. Experiments show that this algorithm could effectively improve the clustering results.

Abstract:Genetic algorithm can do colony global searching quickly and stochastically, but can’t efficiently get to optimal results, since it slows down when solving to certain scope. On the other hand, ant algorithm gets to optimal results efficiently, but lacks initial pheromone at the beginning. To solve the hardware/software bi-partitioning problem in embedded system and system-on-a-chip design, the authors put forward a new algorithm based on dynamic combination of genetic algorithm and ant algorithm. The basic idea is: (1) using genetic algorithm to generate preliminary partitioning results, converting them into initial pheromone distribution for ant algorithm, and then using ant algorithm to search for optimal partitioning scheme; (2) while running genetic algorithm, dynamically determining the best combination time of genetic algorithm and ant algorithm to avoid too early or too late termination of the genetic algorithm. The algorithm utilizes the advantages of the two algorithms and overcomes their disadvantages, and it introduces a dynamic combination strategy between them. Experimental results show the algorithm excels genetic algorithm and ant algorithm in performance, and it is discovered that the bigger the partitioning problem is concerned, the better the algorithm performs.

Abstract:An extended class cover problem is presented and then it is reduced to a constrained multi-objective optimization problem. Solving this problem is significantly important to construct a robust classification system. Therefore, through analyzing the parameters of the binary particle swarm optimization, the conclusion that the binary particle swarm optimization can not only explore the search space efficiently, but also utilize the apriori knowledge adequately, is drawn in this paper. Furthermore, a hybrid algorithm combined with the conventional greedy algorithm and binary particle swarm optimization algorithm is proposed to deal with the extended class cover problem. The proposed algorithm can get a better solution in less runtime and the simulated comparative results with other algorithms show its feasibility and validity.

Abstract:A novel recognition method called Active Discriminant Function (ADF) for handwriting recognition is presented. First, statistical feature based Active Prototype Model (APM) in the principal subspace is proposed and an optimal APM corresponding to an unknown pattern is obtained. Second, ADF that is a weighted summation of two distances is proposed. One measures the distance between an unknown pattern and the principal subspace; the other measures the distance between an unknown pattern and the minor subspace. Third, as parameters of ADF, constraints for APM are optimized by applying Minimum Classification Error (MCE) criterion. The optimal constraints help to improve recognition accuracy of ADF. Finally, experiments are conducted on handwritten financial Chinese characters used in bank bill, and empirical results demonstrate that ADF is fairly promising for handwriting recognition.

Abstract:To combine XML with relations is a hotspot in research field. This paper studies the functional dependency and normalization propagation between relations and XML. First the paper gives the definition of functional dependencies and keys for XML; based on it, the concepts of redundancy and DTD normalization are defined. The paper then discusses the functional dependency propagation between relations and XML. When using a general mapping from relational schema to DTD, the paper shows that all the relational functional dependencies can be preserved in the DTD; and when applying a commonly used method to mapping DTD to relational schema, each functional dependency on relations has a corresponding one in the original DTD. The significance of functional dependency propagation lies in the normalization propagation. The paper proves that using the methods above, if the original relation is in BCNF, the generated DTD is normalized, and if the original DTD is normalized, the generated relations are in BCNF.

Abstract:Most of the existing peer-to-peer (P2P) systems only support simple title-based search, and users cannot search the data based on their content. Top-k query is widely used in the search engine and gains great success. However, Processing top-k query in pure P2P network is very challenging because a P2P system is a dynamic and decentralized system. An efficient hierarchical top-k query processing algorithm based on histogram is proposed. First, a distributed query processing model for top-k query is proposed. It does top-k query in a hierarchical way. Ranking and merging of documents are distributed across the peers, which takes full advantage of the computing resource of the network. Next, a histogram is constructed for each peer according to the top k results returned by the peer, and used to estimate the possible upper bound of the score for the peer. By the histogram information, the most possible peers are selected to send the query, so as to greatly improve the search efficiency. Experimental results show that the top-k query improves the query effectiveness, and the histogram improves the query efficiency.

Abstract:Mining maximum frequent itemsets is a key problem in data mining field with numerous important applications. The existing algorithms of mining maximum frequent itemsets are based on local databases, and very little work has been done in distributed databases. However, using the existing algorithms for the maximum frequent itemsets or using the algorithms proposed for the global frequent itemsets needs to generate a lots of candidate itemsets and requires a large amount of communication overhead. Therefore, this paper proposes an algorithm for fast mining global maximum frequent itemsets (FMGMFI), which can conveniently get the global frequency of any itemset from the corresponding paths of every local FP-tree by using frequent pattern tree and require far less communication overhead by the searching strategy of bottom-up and top-down. Experimental results show that FMGMFI is effective and efficient.

Abstract:Result size estimation of value predication in XML query is a multiple attributes dependent problem. It is different from the counterpart in relational database, for the multiple attributes in XML involve not only the value data, but also the structural information. To solve the problem, this paper proposes a wavelet-based histogram for the result size estimation of value predication in XML query. It also gives the way to identify the multi-dimensional dependent element set, to rewrite the value predication and value denotation of structural information. Experimental results show that the algorithm achieves on accurate result size estimation for value predication in XML query.

Abstract:Security for composition of protocols is hotspot of international scope. By using composition method, it is proved that the distributed key distribution scheme introduced by Daza et al is secure. The scheme appends verifiable secret sharing and zero-knowledge proofs to the basic one which fits in the case of passive adversary to prevent from the action of an active adversary.

Abstract:This paper presents an e-Science Grid architecture called Virtual and Dynamic Hierarchical Architecture (VDHA). VDHA is a decentralized architecture with some P2P properties. It also has scalable, autonomous, exact, and full service discovery properties. We have implemented a demonstration VDHA_based Grid prototype ? VDHA_Grid, which has scalable Grid information service. VDHA_Grid is the core software for the project of the Chinese University e-Science Grid. In this paper, advantages and several protocols of the VDHA are also discussed.

Abstract:Handoff is an important research topic of mobility support protocols. It has great effects on the performance and quality-of-service of mobile networks. Based on appropriate network model and handoff model, the handoff performance of various mobility support protocols is deeply studied and compared through theoretical analysis and numerical simulation. The comparisons are made between mobile IP and micro-mobility protocol, and between different micro-mobility protocols. The results show that wireless network parameters and route update algorithms of mobility support protocols affect the handoff performance. The handoff performance when applying micro-mobility protocols is better than when only using Mobile IP. In all micro-mobility protocols, the route update algorithm of MIP-RR and MMP has the optimal performance.

Abstract:The n-variable and m-resilient (m>n/2-2) Boolean functions achieving both the upper bound on nonlinearity2^n-1-2^m+1and the upper bound on algebraic degree n-m-1 must have three valued Walsh spectra: 0,±2^m+2,which are called saturated best (SB in short). Using the known results of weight distributions of the cosets of the (32,6) Reed-Muller code and a new construction method for SB functions gives the number of the 5-variable SB functions.

Abstract:LKH (logical key hierarchy) is a basic method in secure multicast group rekeying. LKH is efficient in real time group rekeying since it does not distinguish the different probability among the group members. However when members have diverse changing probability or different changing modes, the gap between LKH and the optimal algorithm will become bigger. If the probabilities of members have been known, LKH can be improved someway, but the changing probability of members can not be known exactly. Based on the basic knowledge of group members, in R-LKH (Refined-LKH), the active members and inactive members are partitioned and set on different locations in the logical key tree firstly. Then the concept “dirty path” is introduced in order to reduce the repeated rekeying overhead in the same path. All these can decrease the number of encryption in group manager and the network communication overhead. The simulation result indicate that R-LKH has a better improvement over LKH if the multicast group members’ behavior could be distinguished “approximately”.

Abstract:To improve the efficiency of group signature, an efficient and secure dynamic group signature scheme is proposed based on the ELGamal encryption and signature of knowledge. It allows the group manager to add new members or delete old members freely. Furthermore, the length of the signature and the computational effort for signing and verifying are independent of the number of the group members and the deleted group members. So it may have many practical applications in e-commerce and military.

Abstract:To some extent, using a plane curve to approximate an offset curve of the plane Bézier curve is restricted. In this paper, a region approximation idea that means using a “fat curve” with a width to approximate the offset curve is proposed, and a complete set of algorithms to approximate offset curve using disk Bézier curve are given and implemented. In the algorithms, the optimal and uniform approximate curve of the offset curve as the central curve of the Disk Bézier curve is found by using Remez method, and then the upper optimal and uniform approximation principle is proposed to compute the error radius function of the Disk Bézier curve. Thus, the whole Disk Bézier curve can be obtained. In the end of this paper, the approximate effect of the Disk Bézier curve is not only analyzed and assessed, but also some specific examples are provided.

Abstract:The basis function of n order hyperbolic polynomial uniform B-spline with shape parameter is constructed so that the shape of the constructed curve can be adjusted by changing the parameter value. The hyperbola can be represented with this basis function accurately. With elevation of the order, feasible range of the shape parameter value is extended.

Abstract:This paper considers the space GC2 Hermite interpolation by cubic B-spline curve which is based on de Boor’s idea for constructing the planar GC2 Hermite interpolation. In addition to position and tangent direction, the curvature vector is interpolated at each point. It is proved that under appropriate assumptions the interpolant exists locally with two degrees of freedom and the 4th order accuracy.