Global-as-view (GAV) constraints form a class of database constraints that has been widely used in the study of data exchange and data integration. Specifically, relationships between different database schemas are commonly described by a schema mapping consisting of a finite set of GAV constraints. Such schema mappings can be viewed as representations of an infinite set of data examples. We st...

A data integration system (DIS) provides access to a set of heterogeneous data sources through a so-called global schema. There are basically two approaches for designing a DIS. In the global-as-view (GAV) approach, one defines the elements in the global schema as views over the sources, whereas in the local-as-view (LAV) approach, one characterizes the sources as views over the global schema. ...

A 20089 nucleotide (nt) sequence was determined for the 5' end of the (+)-ssRNA genome of gill-associated virus (GAV), a yellow head-like virus infecting Penaeus monodon prawns. Clones were generated from a approximately 22 kb dsRNA purified from lymphoid organ total RNA of GAV-infected prawns. The region contains a single gene comprising two long overlapping open reading frames, ORF1a and ORF1...

Data Integration is the process of combining data residing at different sources with associated local schemas to form a single virtual database with an associated global schema [1, 2]. This is to provide the user with a uniform query interface for multiple independent heterogeneous data sources [3, 4]. There are four main approaches of data integration. They are Global As view (GAV), Local As V...

There are basically two approaches for designing a data integration system. In the global-as-view (GAV) approach, one maps the concepts in the global schema to views over the sources, whereas in the local-as-view (LAV) approach, one maps the sources into views over the global schema. The goal of this paper is to relate the two approaches with respect to their expressive power. The analysis is c...

this research was carried out to investigate the cold-hardiness of grapevine buds in a factorial experiment base on completely randomized design (crd) with 80 treatments and three replications. treatments included four cultivars (rish-baba, siyah-e-shiraz, askari and bavanati), four sampling dates (6th dec, 5th jan, 4th feb and 6th mar 2009 and 2010) and low temperature levels (+5, -7, -15, -22...

the siyah bisheh area is located in central part of alborz zone, 40km south of amol, iran. rock units exposing in the area consists of sedimentary (carbonates, sandstone, siltstone), volcano- sedimentary (andesite to andesitic tuff, tuff), ignimbrite and basalt. when erosion and tectonics have rendered volcanic structures undetectable, remote sensing provides an invaluable tool for their ide...

A highly sensitive test based on reverse transcription followed by nested polymerase chain reaction (RT-nPCR) was developed to detect the Australian yellow-head-like viruses, gill-associated virus (GAV) and lymphoid organ virus (LOV) of Penaeus monodon. The RT-nPCR detected viral RNA in as little as 10 fg lymphoid organ total RNA isolated from GAV-infected P. monodon. Amplification of serial di...