40 research outputs found

    Eventsummarizer: a tool for summarizing large event sequences

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    ABSTRACT We present EventSummarizer -a tool for extracting comprehensive summaries from large event sequences. EventSummarizer takes as input a sequence with events of different types that occur during an observation period, and creates a partitioning of this time period into contiguous nonoverlapping intervals such that each interval can be described by a simple model. Within each interval local associations between events of different types are reported. EventSummarizer runs on top of any Relational DataBase Management System (RDBMS), on tables with a timestamp attribute. Our system is parameter free and has a visual interface that provides the user with a global view of the input sequence via the segmentation of the timeline. The easyto-use interface provides the user with the option to further examine the activity and associations of event types within each segment

    Supporting deductive and active rules on top of a relational DBMS

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    Policy-Based Management and Sharing of Sensitive Information among Government Agencies

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    We propose a set of policy-based technologies to enable increased information sharing among government agencies without compromising information security or individual privacy. Our approach includes: (1) finegrained access controls that support deny and filter semantics to satisfy complex policy conditions; (2) a sticky policy capability that allows consolidation of information from multiple sources subject to the original disclosure policies of each source; (3) a curation organization that enables agencies to apply and manipulate item-level security classifications and disclosure policies; (4) an auditing system that accounts for the curation history of each information item; and (5) a provenance auditing method that traces derivations of information over time to support evaluations of information quality. Our goal is to present a vision for solving outstanding information sharing problems in government agencies and provide direction for the development of future government information systems. 1

    Server-Centric P3P

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    We propose a server-centric architecture for P3P that reuses database technology for implementation, as opposed to the prevailing client-centric implementations based on specialized engines. The server-centric implementation has several advantages including: setting up the infrastructure necessary for ensuring that web sites act according to their stated policies, allowing P3P to be deployed in thin, mobile clients that are likely to dominate Internet access in the future, and allowing site owners to refine their policies based on the privacy preferences of their users. Our experiments indicate that it performs significantly better than the sole public-domain client-centric implementation and that the latency introduced by preference matching is small enough for real-world deployments of P3P. We believe a good future direction for P3P would be to standardize on the server-centric architecture as an alternative to the current client-centric architecture
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