Página 1 dos resultados de 760 itens digitais encontrados em 0.013 segundos

## Uma ferramenta para teste estrutural de regras ativas

Virginia Mara Cardoso
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Relevância na Pesquisa
26.11%

## Gerenciamento de regras de qualidade em cadeias produtivas; Monitoring quality in supply chains : a rule-based approach

Mauricio Augusto Figueiredo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
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## Variation in isometric force after active shortening and lengthening and their mechanisms: a review

Lima,Rodrigo Troyack de; Farinatti,Paulo; Monteiro,Walace; Oliveira,Carlos Gomes de
Tipo: Artigo de Revista Científica Formato: text/html
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Introduction The isometric force history dependence of skeletal muscle has been studied along the last one hundred years. Several theories have been formulated to explain and establish the causes of the phenomenon, but not successfully, as they have not been fully accepted and demonstrated, and much controversy on such a subject still remains. Objective To present a systematic literature review on the dynamics of the mechanisms of force depression and force enhancement after active shortening and lengthening, respectively, identifying the key variables involved in the phenomenon, and to date to present the main theories and hypothesis developed trying to explaining it. Method The procedure of literature searching complied the major databases, including articles either, those which directly investigated the phenomena of force depression and force enhancement or those which presented possible causes and mechanisms associated with their respective events, from the earliest studies published until the year of 2010. Results 97 references were found according to the criteria used. Conclusion Based on this review, it is suggested that the theory of stress inhibition of actin-myosin cross-bridges is that better explain the phenomenon of force depression. Whereas regarding the force enhancement phenomenon...

## Active In-Database Processing to Support Ambient Assisted Living Systems

de Morais, Wagner O.; Lundström, Jens; Wickström, Nicholas
Tipo: Artigo de Revista Científica
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As an alternative to the existing software architectures that underpin the development of smart homes and ambient assisted living (AAL) systems, this work presents a database-centric architecture that takes advantage of active databases and in-database processing. Current platforms supporting AAL systems use database management systems (DBMSs) exclusively for data storage. Active databases employ database triggers to detect and react to events taking place inside or outside of the database. DBMSs can be extended with stored procedures and functions that enable in-database processing. This means that the data processing is integrated and performed within the DBMS. The feasibility and flexibility of the proposed approach were demonstrated with the implementation of three distinct AAL services. The active database was used to detect bed-exits and to discover common room transitions and deviations during the night. In-database machine learning methods were used to model early night behaviors. Consequently, active in-database processing avoids transferring sensitive data outside the database, and this improves performance, security and privacy. Furthermore, centralizing the computation into the DBMS facilitates code reuse, adaptation and maintenance. These are important system properties that take into account the evolving heterogeneity of users...

## Uma arquitetura para monitoramento de banco de dados e recomendações utilizando sistema de banco de dados ativos

Santos, Paulo Henrique dos
POR
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Integrated environments monitoring can become complex with heterogeneous databases, due to the particularities in the language syntax and available tools. In particular, active databases allow developing mechanisms and automation of processes involving data or objects. This work proposes the development of an architecture to identify and monitor DDL (Data Definition Language), exploring the active databases and recommendations approach. This architecture could be explored in several ways: simple monitoring of DDL events in one or more databases, or recommendation of future DDLs or settings within the monitored database. In this context, this work proposes: (i) an integrated architecture of active databases and recommendation; (ii) the adaptation of a recommendation algorithm; and (iii) the validation of concepts through a prototype.; O monitoramento de forma integrada pode se tornar complexo em ambientes com bancos de dados heterogêneos, devido às particularidades na sintaxe e em ferramentas disponíveis. Em particular, bancos de dados ativos permitem o desenvolvimento de mecanismos e a automação de processos que envolvam os dados ou objetos. Este trabalho propõe o desenvolvimento de uma arquitetura para identificar e monitorar eventos DDL (Data Definition Language)...

## OCL2Trigger: Deriving active mechanisms for relational databases using Model-Driven Architecture

Al-Jumaily, Harith T.; Cuadra, Dolores; Martínez, Paloma
Tipo: Artigo de Revista Científica Formato: application/pdf
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Transforming integrity constraints into active rules or triggers for verifying database consistency produces a serious and complex problem related to real time behaviour that must be considered for any implementation. Our main contribution to this work is to provide a complete approach for deriving the active mechanisms for Relational Databases from the specification of the integrity constraints by using OCL. This approach is designed in accordance with the MDA approach which consists of transforming the specified OCL clauses into a class diagram into SQL:2003 standard triggers, then transforming the standard triggers into target DBMS triggers. We believe that developing triggers and plugging them into a given model is insufficient because the behaviour of such triggers is invisible to the developers, and therefore not controllable. For this reason, a DBMS trigger verification model is used in our approach, in order to ensure the termination of trigger execution. Our approach is implemented as an add-in tool in Rational Rose called OCL2Trigger.; This work is part of the "Software Process Management Platform: Modelling, reuse and measurement" TIN2004/07083 project.; 16 pages, 10 figures.-- Issue title: "Best papers from the 2007 Australian Software Engineering Conference (ASWEC 2007)...

## Active or Passive Exposure to Tobacco Smoking and Allergic Rhinitis, Allergic Dermatitis, and Food Allergy in Adults and Children: A Systematic Review and Meta-Analysis

Saulyte, Jurgita; Regueira, Carlos; Montes-Martínez, Agustín; Khudyakov, Polyna; Takkouche, Bahi
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
EN_US
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Background: Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS) or passive exposure to secondhand smoke and allergic conditions. Methods and Findings: We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR) or relative risk (RR) estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children. We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR)...

## Verifying Recursive Active Documents with Positive Data Tree Rewriting

Genest, Blaise; Muscholl, Anca; Wu, Zhilin
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.79%
This paper proposes a data tree-rewriting framework for modeling evolving documents. The framework is close to Guarded Active XML, a platform used for handling XML repositories evolving through web services. We focus on automatic verification of properties of evolving documents that can contain data from an infinite domain. We establish the boundaries of decidability, and show that verification of a {\em positive} fragment that can handle recursive service calls is decidable. We also consider bounded model-checking in our data tree-rewriting framework and show that it is $\nexptime$-complete.

## On optimum left-to-right strategies for active context-free games

Björklund, Henrik; Schuster, Martin; Schwentick, Thomas; Kulbatzki, Joscha
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.85%
Active context-free games are two-player games on strings over finite alphabets with one player trying to rewrite the input string to match a target specification. These games have been investigated in the context of exchanging Active XML (AXML) data. While it was known that the rewriting problem is undecidable in general, it is shown here that it is EXPSPACE-complete to decide for a given context-free game, whether all safely rewritable strings can be safely rewritten in a left-to-right manner, a problem that was previously considered by Abiteboul et al. Furthermore, it is shown that the corresponding problem for games with finite replacement languages is EXPTIME-complete.; Comment: To appear in ICDT 2013

## Small-Scale and Global Dynamos and the Area and Flux Distributions of Active Regions, Sunspot Groups, and Sunspots: A Multi-Database Study

Muñoz-Jaramillo, Andrés; Senkpeil, Ryan R.; Windmueller, John C.; Amouzou, Ernest C.; Longcope, Dana W.; Tlatov, Andrey G.; Nagovitsyn, Yury A.; Pevtsov, Alexei A.; Chapman, Gary A.; Cookson, Angela M.; Yeates, Anthony R.; Watson, Fraser T.; Balmaceda,
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.14%
In this work we take advantage of eleven different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of photospheric magnetic structures. We find that, when taken separately, different databases are better fitted by different distributions (as has been reported previously in the literature). However, we find that all our databases can be reconciled by the simple application of a proportionality constant, and that, in reality, different databases are sampling different parts of a composite distribution. This composite distribution is made up by linear combination of Weibull and log-normal distributions -- where a pure Weibull (log-normal) characterizes the distribution of structures with fluxes below (above) $10^{21}$Mx ($10^{22}$Mx). We propose that this is evidence of two separate mechanisms giving rise to visible structures on the photosphere: one directly connected to the global component of the dynamo (and the generation of bipolar active regions), and the other with the small-scale component of the dynamo (and the fragmentation of magnetic structures due to their interaction with turbulent convection). Additionally, we demonstrate that the Weibull distribution shows the expected linear behavior of a power-law distribution (when extended into smaller fluxes)...

## repAIrC: A Tool for Ensuring Data Consistency by Means of Active Integrity Constraints

Cruz-Filipe, Luís; Franz, Michael; Hakhverdyan, Artavazd; Ludovico, Marta; Nunes, Isabel; Schneider-Kamp, Peter
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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Consistency of knowledge repositories is of prime importance in organization management. Integrity constraints are a well-known vehicle for specifying data consistency requirements in knowledge bases; in particular, active integrity constraints go one step further, allowing the specification of preferred ways to overcome inconsistent situations in the context of database management. This paper describes a tool to validate an SQL database with respect to a given set of active integrity constraints, proposing possible repairs in case the database is inconsistent. The tool is able to work with the different kinds of repairs proposed in the literature, namely simple, founded, well-founded and justified repairs. It also implements strategies for parallelizing the search for them, allowing the user both to compute partitions of independent or stratified active integrity constraints, and to apply these partitions to find repairs of inconsistent databases efficiently in parallel.; Comment: IMADA-preprint-cs

## Active Integrity Constraints and Revision Programming

Caroprese, L.; Truszczynski, M.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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We study active integrity constraints and revision programming, two formalisms designed to describe integrity constraints on databases and to specify policies on preferred ways to enforce them. Unlike other more commonly accepted approaches, these two formalisms attempt to provide a declarative solution to the problem. However, the original semantics of founded repairs for active integrity constraints and justified revisions for revision programs differ. Our main goal is to establish a comprehensive framework of semantics for active integrity constraints, to find a parallel framework for revision programs, and to relate the two. By doing so, we demonstrate that the two formalisms proposed independently of each other and based on different intuitions when viewed within a broader semantic framework turn out to be notational variants of each other. That lends support to the adequacy of the semantics we develop for each of the formalisms as the foundation for a declarative approach to the problem of database update and repair. In the paper we also study computational properties of the semantics we consider and establish results concerned with the concept of the minimality of change and the invariance under the shifting transformation.; Comment: 48 pages...

## Introducing Dynamic Behavior in Amalgamated Knowledge Bases

Bertino, Elisa; Catania, Barbara; Perlasca, Paolo
Tipo: Artigo de Revista Científica
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The problem of integrating knowledge from multiple and heterogeneous sources is a fundamental issue in current information systems. In order to cope with this problem, the concept of mediator has been introduced as a software component providing intermediate services, linking data resources and application programs, and making transparent the heterogeneity of the underlying systems. In designing a mediator architecture, we believe that an important aspect is the definition of a formal framework by which one is able to model integration according to a declarative style. To this purpose, the use of a logical approach seems very promising. Another important aspect is the ability to model both static integration aspects, concerning query execution, and dynamic ones, concerning data updates and their propagation among the various data sources. Unfortunately, as far as we know, no formal proposals for logically modeling mediator architectures both from a static and dynamic point of view have already been developed. In this paper, we extend the framework for amalgamated knowledge bases, presented by Subrahmanian, to deal with dynamic aspects. The language we propose is based on the Active U-Datalog language, and extends it with annotated logic and amalgamation concepts. We model the sources of information and the mediator (also called supervisor) as Active U-Datalog deductive databases...

## Declarative Semantics for Active Rules

Flesca, Sergio; Greco, Sergio
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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In this paper we analyze declarative deterministic and non-deterministic semantics for active rules. In particular we consider several (partial) stable model semantics, previously defined for deductive rules, such as well-founded, max deterministic, unique total stable model, total stable model, and maximal stable model semantics. The semantics of an active program AP is given by first rewriting it into a deductive program P, then computing a model M defining the declarative semantics of P and, finally, applying `consistent' updates contained in M to the source database. The framework we propose permits a natural integration of deductive and active rules and can also be applied to queries with function symbols or to queries over infinite databases.; Comment: 27 pages

## The World Wide Telescope: An Archetype for Online Science

Gray, Jim; Szalay, Alexander S.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.93%
Most scientific data will never be directly examined by scientists; rather it will be put into online databases where it will be analyzed and summarized by computer programs. Scientists increasingly see their instruments through online scientific archives and analysis tools, rather than examining the raw data. Today this analysis is primarily driven by scientists asking queries, but scientific archives are becoming active databases that self-organize and recognize interesting and anomalous facts as data arrives. In some fields, data from many different archives can be cross-correlated to produce new insights. Astronomy presents an excellent example of these trends; and, federating Astronomy archives presents interesting challenges for computer scientists.; Comment: 6 pages, msword posted at http://research.microsoft.com/research/pubs/view.aspx?tr_id=590

## Games for Active XML Revisited

Schuster, Martin; Schwentick, Thomas
Tipo: Artigo de Revista Científica
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35.88%
The paper studies the rewriting mechanisms for intensional documents in the Active XML framework, abstracted in the form of active context-free games. The safe rewriting problem studied in this paper is to decide whether the first player, Juliet, has a winning strategy for a given game and (nested) word; this corresponds to a successful rewriting strategy for a given intensional document. The paper examines several extensions to active context-free games. The primary extension allows more expressive schemas (namely XML schemas and regular nested word languages) for both target and replacement languages and has the effect that games are played on nested words instead of (flat) words as in previous studies. Other extensions consider validation of input parameters of web services, and an alternative semantics based on insertion of service call results. In general, the complexity of the safe rewriting problem is highly intractable (doubly exponential time), but the paper identifies interesting tractable cases.; Comment: To be published in ICDT 2015

## Active Learning for Crowd-Sourced Databases

Mozafari, Barzan; Sarkar, Purnamrita; Franklin, Michael J.; Jordan, Michael I.; Madden, Samuel
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.12%
Crowd-sourcing has become a popular means of acquiring labeled data for a wide variety of tasks where humans are more accurate than computers, e.g., labeling images, matching objects, or analyzing sentiment. However, relying solely on the crowd is often impractical even for data sets with thousands of items, due to time and cost constraints of acquiring human input (which cost pennies and minutes per label). In this paper, we propose algorithms for integrating machine learning into crowd-sourced databases, with the goal of allowing crowd-sourcing applications to scale, i.e., to handle larger datasets at lower costs. The key observation is that, in many of the above tasks, humans and machine learning algorithms can be complementary, as humans are often more accurate but slow and expensive, while algorithms are usually less accurate, but faster and cheaper. Based on this observation, we present two new active learning algorithms to combine humans and algorithms together in a crowd-sourced database. Our algorithms are based on the theory of non-parametric bootstrap, which makes our results applicable to a broad class of machine learning models. Our results, on three real-life datasets collected with Amazon's Mechanical Turk, and on 15 well-known UCI data sets...

## Active Sampler: Light-weight Accelerator for Complex Data Analytics at Scale

Gao, Jinyang; Jagadish, H. V.; Ooi, Beng Chin
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
35.9%
Recent years have witnessed amazing outcomes from "Big Models" trained by "Big Data". Most popular algorithms for model training are iterative. Due to the surging volumes of data, we can usually afford to process only a fraction of the training data in each iteration. Typically, the data are either uniformly sampled or sequentially accessed. In this paper, we study how the data access pattern can affect model training. We propose an Active Sampler algorithm, where training data with more "learning value" to the model are sampled more frequently. The goal is to focus training effort on valuable instances near the classification boundaries, rather than evident cases, noisy data or outliers. We show the correctness and optimality of Active Sampler in theory, and then develop a light-weight vectorized implementation. Active Sampler is orthogonal to most approaches optimizing the efficiency of large-scale data analytics, and can be applied to most analytics models trained by stochastic gradient descent (SGD) algorithm. Extensive experimental evaluations demonstrate that Active Sampler can speed up the training procedure of SVM, feature selection and deep learning, for comparable training quality by 1.6-2.2x.; Comment: 12 pages

## Kinematics of ionized gas associated with the radio nucleus and lobes in the active galaxy IRAS 04210+0400

Holloway, Anthony; Steffen, Wolfgang; Pedlar, Alan; Axon, David; Dyson, John; Meaburn, John; Tadhunter, Clive
Fonte: Blackwell Publishing: Monthly Notices of the Royal Astronomical Society Publicador: Blackwell Publishing: Monthly Notices of the Royal Astronomical Society
Tipo: Artigo de Revista Científica Formato: 300145 bytes; application/pdf
EN_US
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We have used high resolution longslit spectroscopy to investigate the ionized gas in the active galaxy IRAS 04210+0400 and its association with the radio structure. We suggest that two of the ionized components are associated with the central double radio source and observe that the relative positions of these components vary for different emission lines. Both results are consistent with the radio components representing the working surfaces of a pair of jets emerging from the centre of the galaxy. In this scenario, the optical emission in the centre arises behind the bowshocks produced by the jets in the interstellar medium. The emission lines are detected and show a dramatic ( 900 km s−1) spread in velocity at the position of the radio lobe hotspots. We suggest a model which explains this phenomenon as the result of a jet head emerging through the boundary between the interstellar and intergalactic medium. A similar scenario has previously been suggested as a model to explain wide angle tail radio sources (WAT’s). Based on this model, we simulate the longslit spectra of these regions and compare the results with the observations. (Refer to PDF file for exact formulas).; Also archived in: arXiv:astro-ph/9510001 v1 2 Oct 1995; RIT community members may access full-text via RIT Libraries licensed databases: http://library.rit.edu/databases/; AJH and WS acknowledge the receipt of a PPARC studentship and PPARC research associateship respectively.

## Implementation of active collections framework using .NET

Magdum, Sushil
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Masters Project
EN_US
Relevância na Pesquisa
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For many years, large distributed enterprises have faced a common problem of near real time sharing of enterprise data typically stored in databases. As these databases may be located globally, distributed nature of this data makes it difficult to access instantaneously. The Active Collections Framework (ACF) acts as a good foundation on which to build distributed applications. This framework requires distributed applications to view changes to data as events of interest. The ACF framework integrates access to data and data changes through active collections. ACF framework is based on two different research areas: event management in distributed computing and active database systems. Active databases support mechanisms to monitor changes to the database state. The central concept in ACF event management is active collections. Each active collection is a collection of all objects specified by a query on the enterprise data. For each client interested in obtaining data, an entry is made in the active collection. This information is then used by windows service to notify the registered client of any data changes. This project implements the Active Collections Framework using Microsoft .Net and Visual Studio .Net. Two sample applications using the developed framework have been developed to demonstrate the efficiency of data storage and event notification capabilities of the developed ACF framework.