OWL Ontologies may change continually to meet user's dynamic request and it may damage the integrity of the ontology. Thus, it is in urgent to propose an effective strategy to maintain the integrity of the continu...
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In this paper, we outline the problem of multi-join ordering query optimization in the semantic web scenario, also known as SPARQL BGP (Basic Graph Pattern) reordering optimization. Unlike most previous researches, we...
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In this paper, we outline the problem of multi-join ordering query optimization in the semantic web scenario, also known as SPARQL BGP (Basic Graph Pattern) reordering optimization. Unlike most previous researches, we concentrate on more general SPARQL query forms and devote ourselves to the problem of searching for the optimal query plan within a more complete search space-bushy plan space. We model the BGP reordering optimization as a genetic evolution problem and implement a genetic algorithm on the open-source Jena ARQ System. With carefully design of the chromosome encoding scheme and the cost model, the final experimental results show that our method outperforms the common heuristics method and is comparable with some other state-of-the-art optimization methods w.r.t. the output quality.
Except common security and privacy requirements, well scalability and supporting tag ownership transfer are important requests for RFID systems. In this paper, an efficient RFID mutual authentication protocol supporti...
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Except common security and privacy requirements, well scalability and supporting tag ownership transfer are important requests for RFID systems. In this paper, an efficient RFID mutual authentication protocol supporting tag ownership transfer is proposed, this protocol only requires O(1) work to identify and authenticate a tag in the backend server and is suitable for the low-cost RFID systems. The security and performance of the proposed protocol are analyzed as well.
The purpose of this paper is to study the topological relations of four simple regions. We extend 4-intersection matrix model to 16-intersections matrix model to represent the spatial relations of four simple regions,...
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The purpose of this paper is to study the topological relations of four simple regions. We extend 4-intersection matrix model to 16-intersections matrix model to represent the spatial relations of four simple regions, and prove that these topological relations are exclusive and complete. Moreover, we obtained 32406 topological relations in practice by programs, and we illustrate that the 16-intersections matrix model has stronger expressive ability than the topological relations given by RCC-5 in pairs.
This paper presents an efficient technique for processing of 3D meshed surfaces via spherical wavelets. More specifically, an input 3D mesh is firstly transformed into a spherical vector signal by a fast low distortio...
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This paper presents an efficient technique for processing of 3D meshed surfaces via spherical wavelets. More specifically, an input 3D mesh is firstly transformed into a spherical vector signal by a fast low distortion spherical parameterization approach based on symmetry analysis of 3D meshes. This signal is then sampled on the sphere with the help of an adaptive sampling scheme. Finally, the sampled signal is transformed into the wavelet domain according to spherical wavelet transform where many 3D mesh processing operations can be implemented such as smoothing, enhancement, compression, and so on. Our main contribution lies in incorporating a fast low distortion spherical parameterization approach and an adaptive sampling scheme into the frame for pro- cessing 3D meshed surfaces by spherical wavelets, which can handle surfaces with complex shapes. A number of experimental ex- amples demonstrate that our algorithm is robust and efficient.
An imbalanced data classification algorithm named as SBoost is proposed. SBoost regards the decision tree as a weak classifier. Only the instances that their prediction value is more than the threshold are updated wit...
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An imbalanced data classification algorithm named as SBoost is proposed. SBoost regards the decision tree as a weak classifier. Only the instances that their prediction value is more than the threshold are updated with their weights in every iteration. At the beginning of each iteration, SBoost makes use of data generation method to add synthetic minority class instances in order to balance training information. After the sub-classifier is formed, the algorithm deletes the synthetic instances that are not correctly classified. This paper puts forwards the theoretical analysis of training error bound. The experimental results show that SBoost has advantages on imbalanced data classification problem.
In this paper, based on the newly introduced mappings ξi (x, yi) ∈ Rn, i = 1, , m and ηi (x, zj) ∈ Rn, j = 1, , l, using the idea of homotopy methods, we propose a homotopy interior point method for solving the op...
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Clustering semi-structured dataset is a hot research topic recent years. In this paper, we proposed an algorithm named LESC to cluster XML documents collection by the leaf elements. First, we discuss the basic princip...
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knowledge Reformulation and Abstraction model have been proposed to be a model of representation change that includes both syntactic reformulation and abstraction. We furthermore extended the process on the basis of t...
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knowledge Reformulation and Abstraction model have been proposed to be a model of representation change that includes both syntactic reformulation and abstraction. We furthermore extended the process on the basis of the ontology classes and the mappings between them and particularly the concept of goal perception is proposed to formalize the goal-based hierarchical process of workflow abstraction modeling. This paper furthermore introduces system-centered ontology to formalize the hierarchical workflow modeling process. We propose the concept of workflow fragment-based ontology class and provide its hierarchical abstraction process respectively from the object-based perspective and the flow-based perspective, i.e., workflow fragment abstraction and workflow fragment aggregation. Workflow fragment-based ontology class gives the mechanism of system-centered knowledge learning, sharing and reuse to save the cost of redesign and remodeling of workflow models. The hierarchical workflow abstraction model based on workflow fragments (from the perspective on the basis of system-centered ontology) is constructed which is more abstract than based on object-centered and simplifies the reasoning.
Abstraction is a pervasive behavior of people's perception, conceptualization and reasoning. The knowledge reformulation and abstraction model has been introduced to formalize the workflow abstraction modeling pro...
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Abstraction is a pervasive behavior of people's perception, conceptualization and reasoning. The knowledge reformulation and abstraction model has been introduced to formalize the workflow abstraction modeling process which is an iterative learning process of "Perception-Abstraction". The concept of domain is introduced into the general knowledge reformulation and abstraction model to extensionally extend the reasoning ability. In this paper, we provide the process of multi-domain workflow abstraction modeling on the basis of the extended general knowledge reformulation and abstraction model. We think of the steps of the workflow as multi-domain tasks, i.e., they can play different roles in different workflows. By perceiving the tasks that work in multiple domains, we define the multi-domain tasks and through them build the multi-domain relations between different workflow, so that the multi-domain workflow perception is constructed which shows more reasoning perspectives than the single-domain workflow model.
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