Global Schema Research Articles

Information Extraction from the Un-Structured Document using Grammatical Inference and Alignment Similarity

Huge amount of information is available in un-structured (text) documents. Knowledge discovery in un-structured document has been recognized as promising task in the recent years. Since un-structured document is typically formatted for human viewing, it varies widely from document to document. Frequent changes made to their formatting further causes difficulty in construction of a global schema. So, Discovery of interesting rules form it is complex and tedious process. Most of the existing system uses hand-coded wrappers to extract information, which is monotonous and time consuming. In this paper we propose a novel and hybrid approach of learning (context-free) grammar rules that are based on alignment between texts. Also it automatically discovers the grammar rules using grammatical inference of repeated pattern present in un-structured (text) document. The generated rules can be used to infer the attribute value pairs from the unstructured text document.

Query Reformulation: Data Integration Approach to Multi Domain Query Answering System

Data integration gives the user with a unified view of all heterogeneous data sources. The basic service provided by data integration is query processing. Whatever query posed to the system is being given to global schema which has to reformulate to sub queries that are to be posed to the local sources. Reformulation is being accomplished by mapping between global and local sources by Global-as-View (GAV), Local-as-view (LAV) and Global-local-as-view (GLAV) approach. When a query involves multiple domains, it is difficult to extract information in case of general service engines.

Tableaux-based optimization of schema mappings for data integration

The task of combining data residing at different sources to provide the user a unified view is known as data integration. Schema mappings act as glue between the global schema and the source schemas of a data integration system. Global-and-local-as-view (GLAV) is one the approaches for specifying the schema mappings. Tableaux are used for expressing queries and functional dependencies on a single database. We investigate a general technique for expressing a GLAV mapping by a tabular structure called mapping assertion tableaux (MAT). In a similar way, we also express the tuple generating dependency (tgd) and equality generating dependency (egd) constraints by tabular forms, called tabular tgd (TTGD) and tabular egd (TEGD), respectively. A set consisting of the MATs, TTGDs and TEGDs are called schema mapping tableaux (SMT). We present algorithms that use SMT as operator on an instance of the source schema to produce an instance of the target schema. We show that the target instances computed by the SMT are `minimal' and `most general' in nature. We also define the notion of equivalence between the schema mappings of two data integration systems and present algorithms that optimize schema mappings through the manipulation of the SMT.

Lightweight XML semantic integration: a global schema independent approach

In recent years XML has established its position as one of the most prevalent technologies for data exchange. However, its widespread but uncontrolled use has generated vast amounts of semantically alike but structurally different XML data sources. This hinders the ability to meaningfully synthesise related information which partially defeats the purpose of XML. Many solutions have been proposed for the integration of XML semantics, most of which rely on the creation of a global mediated schema. In this paper, we present a novel approach for decentralised integration of heterogeneous XML data sources; thus eliminating the need to create and maintain a global schema. Moreover, our solution is portable which enables the XML data sources to be semantically integrated into different systems without additional efforts. We achieved these objectives by introducing two new components namely, XML semantic schema (XMLSS) and XML semantic query language (XMLSQL), and by providing a query translation algorithm to translate XMLSQL to standard XQuery.

Local Schemas Modifications Propagation and Maintenance of Metadata in Multidatabase System

of the challenging problems in the multidatabase systems is to find the most viable solution to the problem of interoperability of distributed heterogeneous autonomous local component databases. This has resulted in the creation of a global schema over set of local component database schemas to provide a uniform representation of local schemas. The main objective of this paper is to maintain the Global Schema and the Global Directory/Dictionary/Metadata as the local schemas are autonomous and evolve over time. In this paper we consider uniform object-oriented data models which is used during integration of different heterogeneous distributed databases from different data models and proposed a framework to maintain an objected-oriented Global Schema in the multidatabase system. The Bottom up local schema modifications propagation in the Global schema is proposed and during this process the Global Directory/Dictionary/Metadata is maintained without manual intervention.

Evolução motora de paciente com mucopolissacaridose tipo 1

OBJETIVO: Relatar os aspectos funcionais de uma criança com mucopolissacaridose tipo 1, descrevendo suas principais alterações após breve tratamento fisioterapêutico. DESCRIÇÃO DE CASO: Criança com 34 meses, portadora de mucopolissacaridose tipo 1 iniciou tratamento fisioterapêutico, duas vezes por semana, durante 50 minutos, sendo avaliada mensalmente por meio das atividades propostas pela Escala de Desenvolvimento Motor (EDM), que analisa a motricidade fina e global, o equilíbrio, o esquema corporal e a organização temporal e espacial. Na primeira avaliação, a criança apresentava-se com 34 meses de idade cronológica e 18 meses de idade motora geral, com melhor pontuação no item organização espacial, segundo a EDM. Após quatro meses, a idade motora geral era de 20 meses; porém, houve melhora da motricidade global. COMETÁRIOS: A análise das atividades funcionais do paciente relatado demonstrou atraso no desenvolvimento motor. A intervenção terapêutica possibilitou evolução favorável, principalmente na motricidade global, mesmo tratando-se de um portador de doença evolutiva.

SHRDIS: A Semantic-Based Heterogeneous Relational Data Integration System

Integrating and querying data from heterogeneous sources is a hot research topic in database research field. The emergence of the Semantic Web brings new paradigm shift of computing in data integration research where data is heterogeneous and distributed. To solve the problem this paper proposes a semantic-based approach. A Semantic-based Heterogeneous Relational Data Integration System, called SHRDIS, is presented. In this system, ontology is used as the mediated schema for the representation of the data source semantics. SPARQL queries over global schema are rewritten into local SQL queries that can be executed on heterogeneous relational databases. The architecture and implementation of SHRDIS is illustrated in detail. The experiment results show that the SHRDIS system has nice performance and scalability.

Integration of Fuzzy Databases: Problems & Solutions

In this paper, problems in integration of fuzzy relational databases have been investigated and some solutions have been proposed. In general, database integration consists of two main processes called schema integration and instance integration that results into global schema and global instance respectively. Current work assumes a schema integration process to get a global schema from a collection of existing (local) fuzzy relational databases. Instance integration can be classified into three distinct levels according to the extent to which instance integration is carried out. We have focused only on the level-0 instance integration. There are two major problems in instance integration: entity identification; and attribute value conflict resolution that has been discussed in the context of fuzzy database integration and a solution is proposed.

Extracting Data Records Based on Global Schema

With the rapid increasing of web data, deep web is the fastest growing web data carrier. Therefore, the research of deep web, especially on extracting data records from Result pages, has already become an urgent task. We present a data records extraction based on Global Schema method, which automatically extracts the query result records from web pages. This method first analyzes the Query interface and result records instances to build a Global Schema by ontology. Then, the Global Schema is used in the process of extracting data records from result pages and storing these data in a table. Experimental results indicate that this method is accurate to extract data records, as well as to save in a table with a Global Schema.

Group Schema Therapy for Eating Disorders: A Pilot Study

This paper describes the use of Group Schema Therapy for Eating Disorders (ST-E-g) in a case series of eight participants with chronic eating disorders and high levels of co-morbidity. Treatment was comprised of 20 sessions which included cognitive, experiential, and interpersonal strategies, with an emphasis on behavioral change. Specific schema-based strategies focused on bodily felt-sense and body-image, as well as emotional regulation skills. Six attended until end of treatment, two dropped-out at mid-treatment. Eating disorder severity, global schema severity, shame, and anxiety levels were reduced between pre- and post-therapy, with a large effect size at follow-up. Clinically significant improvement in eating severity was found in four out of six completers. Group completers showed a mean reduction in schema severity of 43% at post-treatment, and 59% at follow-up. By follow-up, all completers had achieved over 60% improvement in schema severity. Self-report feedback suggests that group factors may catalyze the change process in schema therapy by increasing perceptions of support and encouragement to take risks and try out new behaviors, whilst providing a de-stigmatizing and de-shaming therapeutic experience.

A Framework for Creating Global Schema Using Proxy Tables from Distributed Heterogeneous Relational Databases in Multidatabase System

A Framework for Creating Global Schema Using Proxy Tables from Distributed Heterogeneous Relational Databases in Multidatabase System

협업을 위한 XMDR-DSM 시스템 설계에 관한 연구

서비스 기반의 전사적 데이터 통합은 기업 변화의 가속화에 따른 통합적인 데이터 관리가 필요하다. 기업 간 협업은 비즈니스 프로세스를 이용하여 분산된 데이터베이스들에 접근하여 이루어진다. 이러한 접근은 글로벌 쿼리 기반으로 수행되기 때문에 이기종간의 상호운용을 위해서 데이터 이질성, 스키마 이질성, 유효성 검증과 같은 문제가 선결되어야 한다. 따라서 협업은 동적이면서 신뢰성 있는 구조를 갖추어야 한다. 본 논문에서는 협업을 위한 XMDR-DSM(eXtended MetaData Registry-Data Service Mediator) 시스템을 제안한다. XMDR-DSM은 XMDR-DS와 XMDR-DQP, XMDR-DAI로 구성되어 글로벌 스키마와 로컬 스키마간의 매핑을 지원해주고, 데이터 접근 및 통합 서비스를 제공한다. 따라서 이기종 데이터베이스 상호간의 업무 지원이 가능하게 하고, 정보를 재활용 가능한 자산으로 확보할 수 있는 이점과 교환의 표준화를 제시할 수 있다. 그리고 워크플로우 기반의 비즈니스 프로세스 제공할 수 있으므로 일원화된 정보를 관리할 수 있게 된다. 따라서 정보 수명을 증대하고 비용절감을 할 수 있게 된다. In the enterprises the data integration based on service requires integrated data management as the change in the environment of enterprises accelerates. Cooperation among enterprises is accomplished through accessing distributed database using business process. As this approach is performed based on the global query, problems such as data heterogeneity, schema heterogeneity, and verification of validity have to be solved in advance for the interoperability among the heterogeneous system. Thus, cooperation requires dynamic and reliable construction. In this paper, we propose XMDR-DSM (eXtended MetaData Registry-Data Service Mediator) system for cooperation. XMDR-DSM, which is comprised of XMDR-DS, XMDR-DQP, and XMDR-DAI, supports the mapping between global schema and local schema and provides data access and integration service. Therefore, XMDR-DSM enables the mutual support of business operations among heterogeneous database. In addition, it can secure information as reusable asset and the standardization of interchange. Also it can manage unified information since it provides business process based on workflow; therefore, it will be able to increase the life span of information and reduce the cost.

Resource Optimization of Mobile Intelligent System with heart MPLS network

In this paper, we introduce the original Mobile Intelligent System (MIS) in embeded FPGA architecture. This node will allow the construction of autonomous mobile network units which can move in unknowns, inaccessible or hostile environnement for human being, in order to collect data by various sensors and transmits them by routing to a unit of distant process.
 In the sake of improving the performance of transmission, we propose a global schema of QoS management using DiffServ/MPLS backbones. We provide an evaluation of several scenarios for combining QoS IP networks with MIS access network. We conclude with a study on interoperability between QoS patterns in access and backbone networks.

Guest editorial: special issue on data management in peer-to-peer systems

It has been almost a decade since the Peer-to-Peer (P2P) technology first emerged as a promising paradigm for distributed computing. Over the years, we have witnessed a large number of domain specific P2P systems being utilized. For example, BitTorrent and Gnutella enable users to share any digital files (e.g., music files, video, images); ICQ facilitates exchanges of personal messages; SETI@home makes computing cycles of participants available; and LOCKSS pools storage resources to archive document collections. Many data structures and overlays that support resource discovery have also been developed. These include CHORD, CAN, BATON and P-Grid. However, successful deployment is largely associated with sharing of files and resources; most of these P2P systems lack data management capabilities that are typically found in DBMS. The key challenges arise from the scale (large number of peers which far exceeds what traditional distributed databases can handle), the dynamism of the systems (peers can join and leave the network any time), and the lack of a global schema. For this special issue, we invited original and high-quality submissions addressing all aspects of Data Management in Peer-to-peer Systems. Each submission was reviewed by at least two experts in the field. Due to limited space, we could only accept and select seven papers for this special issue. These papers are summarized as follows. The first paper Efficient Range Query Processing in Metric Spaces over Highly Distributed Data by C. Doulkeridis, A. Vlachou, Y. Kotidis and M. Vazirgiannis

Schema mapping and query translation in heterogeneous P2P XML databases

Peers in a peer-to-peer data management system often have heterogeneous schemas and no mediated global schema. To translate queries across peers, we assume each peer provides correspondences between its schema and a small number of other peer schemas. We focus on query reformulation in the presence of heterogeneous XML schemas, including data---metadata conflicts. We develop an algorithm for inferring precise mapping rules from informal schema correspondences. We define the semantics of query answering in this setting and develop query translation algorithm. Our translation handles an expressive fragment of XQuery and works both along and against the direction of mapping rules. We describe the HePToX heterogeneous P2P XML data management system which incorporates our results. We report the results of extensive experiments on HePToX on both synthetic and real datasets. We demonstrate our system utility and scalability on different P2P distributions.

A brief history of somatic practices and dance: historical development of the field of somatic education and its relationship to dance

This article outlines the historical development of somatic movement practices especially as they relate to dance, dancers, and dance education organizations. It begins with historical events, cultural trends, and individual occurrences that led up to the emergence of the classic somatic methods at the turn of the twentieth century (Alexander to Trager). It then defines somatic movement education and therapy, and the growth of three generations of somatic movement programmes. Interview data reveals how a second generation included a large proportion of dancers and speaks to how the bodymind thinking of dance professionals continues to shape the training and development of somatic education, as well as dance somatics. Finally it raises the question of the marginalizing of both dance and somatic education, and points to combining forces with their shared characteristics to alter this location in western culture. Another finding seeks to assess the potency and placement of somatic dance in a global schema.

Retrieving XML data from heterogeneous sources through vague querying

We propose a framework for querying heterogeneous XML data sources. The framework ensures high autonomy to participating sources as it does not rely on a global schema or on semantic mappings between schemas. The basic intuition is that of extending traditional approaches for approximate query evaluation, by providing techniques for combining partial answers coming from different sources, possibly on the basis of limited knowledge about the local schemas (i.e., key constraints). We define a query language and its associated semantics, that allows us to collect as much information as possible from several heterogeneous XML sources. We provide algorithms for query evaluation and characterize the complexity of the query language. Finally, we validate the approach in a medical application scenario.

Generic schema mappings for composition and query answering

In this article, we present extensional mappings, that are based on second-order tuple generating dependencies between models in our Generic Role-based Metamodel GeRoMe. Our mappings support data translation between heterogeneous models, such as XML schemas, relational schemas, or OWL ontologies. The mapping language provides grouping functionalities that allow for complete restructuring of data, which is necessary for handling object oriented models and nested data structures such as XML. Furthermore, we present algorithms for mapping composition and optimization of the composition result. To verify the genericness, correctness, and composability of our approach we implemented a data translation tool and mapping export for several data manipulation languages. Furthermore, we address the question how generic schema mappings can be harnessed for answering queries against an integrated global schema.

Query generation for retrieving data from distributed semistructured documents using a metadata interface

We describe a method for generating queries for retrieving data from distributed heterogeneous semistructured documents, and its implementation in the metadata interface DDXMI (distributed document XML metadata interchange). The proposed system generates local queries appropriate to local schemas from a user query over the global schema. The system constructs mappings between global schema and local schemas (extracted from local documents if not given), path substitution, and node identification for resolving the heterogeneity among nodes with the same label that often exist in semistructured data. The system uses Quilt as its XML query language. An experiment is reported over three local semistructured documents: ‘thesis’, ‘reports’, and ‘journal’ documents with ‘article’ global schema. The prototype was developed under Windows system with Java and JavaCC.

P2P OLAP: Data model, implementation and case study

It is a common situation nowadays that business groups own different companies that operate in an autonomous way. Nevertheless, these companies must be requested to provide the headquarters with summarized information for decision-making. An architecture for cooperative interchange of decision-making information seems to be a natural solution for this problem. We propose the use of a peer-to-peer (P2P) architecture for addressing the problem of processing OLAP data in a distributed environment, in a way that all companies involved can maintain full autonomy over the use of its own data resources. In a scenario like this, data exchange between peers occurs when one of them, in the role of a local peer, receives a query and, for answering it, requests data available in other nodes, denoted acquaintances. No global schema is assumed to exist for any data under this computing paradigm. Henceforth, data provided by an acquaintance of a local peer must be adapted, in a manner that answers to queries posed by local peer users conform the view those users have of their data. Because multidimensional data normally consist of a collection of views of aggregated data, a careful translation process is needed in this case, in order to transform any summary concept that appears in a peer acquaintance into a summary concept meaningful to the requesting peer. We first present a model for multidimensional data distributed in a P2P network, and a query rewriting technique, that allows a local peer to propagate OLAP queries among its acquaintances, obtaining a meaningful and correct answer. Mappings are performed using a novel technique called revise and map, based on belief revision concepts. Revising a dimension instance allows to produce consistent aggregations when an OLAP query is answered at more than one node. We then describe an implementation of a P2P system for answering OLAP queries over a network of data warehouses. We apply our proposal to a real-world case study of an insurance group. Finally, we report the results of an experimental evaluation of our implementation, and discuss the issues that must be accounted for in this setting.