3,919 research outputs found
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Automatic parsing of sports videos with grammars
Motivated by the analogies between languages and sports videos, we introduce a novel
approach for video parsing with grammars. It utilizes compiler techniques for integrating both semantic
annotation and syntactic analysis to generate a semantic index of events and a table of content for a given
sports video. The video sequence is first segmented and annotated by event detection with domain
knowledge. A grammar-based parser is then used to identify the structure of the video content.
Meanwhile, facilities for error handling are introduced which are particularly useful when the results of
automatic parsing need to be adjusted. As a case study, we have developed a system for video parsing in
the particular domain of TV diving programs. Experimental results indicate the proposed approach is
effectiv
TSKY: a dependable middleware solution for data privacy using public storage clouds
Dissertação para obtenção do Grau de Mestre em Engenharia InformáticaThis dissertation aims to take advantage of the virtues offered by data storage cloud based systems on the Internet, proposing a solution that avoids security issues by combining different providers’ solutions in a vision of a cloud-of-clouds storage and computing. The solution, TSKY System (or Trusted Sky), is implemented as a middleware system, featuring a set of components designed to establish and to enhance conditions for security, privacy, reliability and availability of data, with these conditions being secured and verifiable by the end-user, independently of each provider. These components, implement cryptographic tools, including threshold and homomorphic cryptographic schemes, combined with encryption, replication, and dynamic indexing mecha-nisms. The solution allows data management and distribution functions over data kept in different storage clouds, not necessarily trusted, improving and ensuring resilience and security guarantees against Byzantine faults and at-tacks. The generic approach of the TSKY system model and its implemented services are evaluated in the context of a Trusted Email Repository System (TSKY-TMS System). The TSKY-TMS system is a prototype that uses the base TSKY middleware services to store mailboxes and email Messages in a cloud-of-clouds
An adaptive multilevel indexing method for disaster service discovery
With the globe facing various scales of natural disasters then and there, disaster recovery is one among the hottest research areas and the rescue and recovery services can be highly benefitted with the advancements of information and communications technology (ICT). Enhanced rescue effect can be achieved through the dynamic networking of people, systems and procedures. A seamless integration of these elements along with the service-oriented systems can satisfy the mission objectives with the maximum effect. In disaster management systems, services from multiple sources are usually integrated and composed into a usable format in order to effectively drive the decision-making process. Therefore, a novel service indexing method is required to effectively discover desirable services from the large-scale disaster service repositories, comprising a huge number of services. With this in mind, this paper presents a novel multilevel indexing algorithm based on the equivalence theory in order to achieve effective service discovery in large-scale disaster service repositories. The performance and efficiency of the proposed model have been evaluated by both theoretical analysis and practical experiments. The experimental results proved that the proposed algorithm is more efficient for service discovery and composition than existing inverted index methods
Poor Man's Content Centric Networking (with TCP)
A number of different architectures have been proposed in support of data-oriented or information-centric networking. Besides a similar visions, they share the need for designing a new networking architecture. We present an incrementally deployable approach to content-centric networking based upon TCP. Content-aware senders cooperate with probabilistically operating routers for scalable content delivery (to unmodified clients), effectively supporting opportunistic caching for time-shifted access as well as de-facto synchronous multicast delivery. Our approach is application protocol-independent and provides support beyond HTTP caching or managed CDNs. We present our protocol design along with a Linux-based implementation and some initial feasibility checks
Efficient Management of Short-Lived Data
Motivated by the increasing prominence of loosely-coupled systems, such as
mobile and sensor networks, which are characterised by intermittent
connectivity and volatile data, we study the tagging of data with so-called
expiration times. More specifically, when data are inserted into a database,
they may be tagged with time values indicating when they expire, i.e., when
they are regarded as stale or invalid and thus are no longer considered part of
the database. In a number of applications, expiration times are known and can
be assigned at insertion time. We present data structures and algorithms for
online management of data tagged with expiration times. The algorithms are
based on fully functional, persistent treaps, which are a combination of binary
search trees with respect to a primary attribute and heaps with respect to a
secondary attribute. The primary attribute implements primary keys, and the
secondary attribute stores expiration times in a minimum heap, thus keeping a
priority queue of tuples to expire. A detailed and comprehensive experimental
study demonstrates the well-behavedness and scalability of the approach as well
as its efficiency with respect to a number of competitors.Comment: switched to TimeCenter latex styl
Data base management system analysis and performance testing with respect to NASA requirements
Several candidate Data Base Management Systems (DBM's) that could support the NASA End-to-End Data System's Integrated Data Base Management System (IDBMS) Project, later rescoped and renamed the Packet Management System (PMS) were evaluated. The candidate DBMS systems which had to run on the Digital Equipment Corporation VAX 11/780 computer system were ORACLE, SEED and RIM. Oracle and RIM are both based on the relational data base model while SEED employs a CODASYL network approach. A single data base application which managed stratospheric temperature profiles was studied. The primary reasons for using this application were an insufficient volume of available PMS-like data, a mandate to use actual rather than simulated data, and the abundance of available temperature profile data
COSPO/CENDI Industry Day Conference
The conference's objective was to provide a forum where government information managers and industry information technology experts could have an open exchange and discuss their respective needs and compare them to the available, or soon to be available, solutions. Technical summaries and points of contact are provided for the following sessions: secure products, protocols, and encryption; information providers; electronic document management and publishing; information indexing, discovery, and retrieval (IIDR); automated language translators; IIDR - natural language capabilities; IIDR - advanced technologies; IIDR - distributed heterogeneous and large database support; and communications - speed, bandwidth, and wireless
Computer integrated documentation
The main technical issues of the Computer Integrated Documentation (CID) project are presented. The problem of automation of documents management and maintenance is analyzed both from an artificial intelligence viewpoint and from a human factors viewpoint. Possible technologies for CID are reviewed: conventional approaches to indexing and information retrieval; hypertext; and knowledge based systems. A particular effort was made to provide an appropriate representation for contextual knowledge. This representation is used to generate context on hypertext links. Thus, indexing in CID is context sensitive. The implementation of the current version of CID is described. It includes a hypertext data base, a knowledge based management and maintenance system, and a user interface. A series is also presented of theoretical considerations as navigation in hyperspace, acquisition of indexing knowledge, generation and maintenance of a large documentation, and relation to other work
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