22971764
Integrating Semantic Web Services for Declarative Accesses in Natural Language
Although extensive research on Web services has been reported in the last decade, problems still remain due to the lack of natural language query support, the lack of automatic service discovery and composition, and the existence of a large number of existing web sites that are query driven. In this paper we introduce a framework that integrates some novel solutions to the above problems. Specifically we differentiate query-based services (QBS) from the traditional function-based services (FBS) and address the following issues: natural language user interface, automatic service discovery and composition, and semantic UDDI
36826410
Web search with personalization and knowledge
Although many search engines provide relevantly good search results to the user, they do not consider personal, domain-specific preferences in their searching or ranking algorithms. In an intranet environment we could collect background information about users such as their expertise. If we can accumulate, categorize and personalize Web usage information, it can be used to help the user search Web pages efficiently and effectively. Data analysis and mining can further facilitate Web searching in an intelligent way. This paper describes Internet Search Advisor (ISA), a personalized, knowledge-driven search system that helps the user find informative Web sites. The ISA supports multi-dimensional data analysis and data mining based on association rules and sequential patterns.
8431943
GPU-friendly warped display for scope-maintained video surveillance
In this paper, we propose an efficient technique for warped display of surveillance video signal. Usually, there are regions of interest (ROIs) in video surveillance, such as entrance or exit, and moving objects or persons. The surveillant has two or more conflicting goals in mind. He/She wants to blow up the ROIs, but also wants to have an overview of the whole surveillance scope. The proposed method solves this conflict by warping the input video signal in real time fashion. First, multiple ROIs are detected. Then, the mesh for texture mapping is deformed, according to the position and shape of the ROIs. The original video frame is mapped as a texture on the deformed mesh to produce the warped effect. Mesh deformation and texture mapping are accelerated by modern graphics processing units (GPU). By allocating more display space for ROIs, the proposed technique highlights such important regions and assists the surveillant to locate them effectively. By experiments, we show that the proposed method is effective and efficient.
12290163
On the Security of the Lee-Hwang Group-Oriented Undeniable Signature Schemes
Undeniable signature is an intriguing concept introduced by Chaum and van Antwerpen at Crypto’89. In 1999, Lee and Hwang presented two group-oriented undeniable signature schemes with a trusted center. Their schemes are natural generalizations of Chaum’s zero knowledge undeniable signature scheme proposed in 1990. However, we find that the Lee-Hwang schemes are insecure. In this paper, we demonstrate five effective attacks on their schemes: four of them are insider universal forgeries, in which one dishonest member (maybe colluding with a verifier) can get a valid signature on any chosen massage, and another attack allows a dishonest member to prevent honest members from generating valid signatures. We also suggest heuristic improvements to overcome some of the problems involved in these attacks.
37556055
A Metadata Tool for Retrieval from Heterogeneous Distributed XML Documents
A metadata approach for retrieval from heterogeneous distributed XMLdo cuments is given. A prototype system uses distributed metadata to generate a GUI data integration tool, for describing mappings between master and local DTDs, by assigning index numbers and specifying conversion functions. A DDXMI (Distributed Document XML Metadata Interchange) file is generated based on the mappings, and used to translate queries over the virtual master document into sub-queries to local documents. Quilt is the XMLq uery language. An experiment testing feasibility is reported using three bibliography documents. The system runs under NT, using Java servelets and JavaCC.
17122000
Efficient and robust key management for large mobile ad hoc networks
Existing research efforts in key management can only handle very limited number of nodes and are vulnerable to active attacks. In addition, the flexibility and adaptivity of handling dynamic risks in different parts of networks, although critical in the practical usages of ad hoc networks, have been largely ignored. In this paper, we propose a novel hierarchical scheme based on threshold cryptography to address both security and efficiency issues of key management and certification service in Mobile Ad hoc Network (MANET). The main contributions of our key management scheme include: 1. providing various parts of MANET the flexibility of selecting appropriate security configurations, according to the risks faced; 2. providing the adaptivity to cope with rapidly-changing environments; 3. handling of MANETs with a large number of nodes; 4. issuing certificates with different levels of assurance. We also propose two algorithms, which can be used independently from the hierarchical structure, to protect certification services in ad hoc networks from active attacks. Our simulation results show that, compared to the previous work [16,18,19], our second algorithm is much faster in a friendly environment. When the key length is 1024 bits, the process of generating or renewing a certificate in our second algorithm is around six to eight times faster, and the process of generating partial certificates in our second algorithm is around 20-80 times faster. The latter advantage is critical in MANET where intrinsically the less help a node requests from its neighbors, the higher is the chance of obtaining the help. Furthermore, simulation results also show that our two algorithms work well in a hostile environment in which existing schemes work poorly.
12571017
A Metadata Integration Assistant Generator for Heterogeneous Distributed Databases
This paper describes a metadata interchange approach for semi-automatedin tegration of heterogeneous distributedd atabases. Our system prototype uses distributed metadata to generate a GUI tool for a meta-user (who does the metadata integration) to describe mappings between master and source databases by assigning index number and specifying conversion function names; the system uses Quilt as its XML query language. The queries for the local databases being transparent for users are generated, which is based on the metadata built semi-automatically. An experiment testing feasibility is reportedin which 3 different publishers' databases are integrated.