149,069 research outputs found
Designing role-based view for object-relational databases
No full textIn a federated database system, a view mechanism is crucial since it is used to define exportable subsets of data ; to perform a virtual restructuring d ataset; and to construct the integrated schema. The view service in federated databa se systems must be capable of retaining as much semantic information as possible. The object-oriented ( 0 - 0 ) model was considered the suitable canonical data model since it meets the original criteria for canonical model selection. However, with the emergence of stronger object-relational (0 -R ) model, the re is a clear argument for using an 0 - R canonical model in the federation. Hence, research should now focus on th e development of semantically powerful view mechanism for th e newer model. Meanwhile, the availability of real 0 -R technologies offers researchers the opportunity to develop different forms of view mechanisms.
The concept of roles has been widely studied in 0 - 0 modelling and development. The role model represents some characteristics that the traditional 0-0 model lacked, such as object migration, multiple occurrences and context-dependent access. While many forms of 0-0 views were designed for the 0-0 canonical model, one option was to extend the 0-0 model to incorporate a role model. In a role model, the real entity is modelled in the form of a role rather than an object. An object represents the permanent properties of an entity is a root object; and an object represents the temporary properties of an entity is a role object.
The contribution of this research is to design a view system that employees the concept of roles for the 0 -R canonical model in a federated database system. In this thesis, an examination of the current 0 -R metamodel is provided first in order to provide an environment for recognising the roleview metadata and measuring the view performance; then a Roleview Definition Language (RDL) is introduced, along with the semantics for defining virtual classes and generating virtua l extents; finally, a working prototype is provided to prove th e role-based view system is implementable and the syntax is semantically correct
ling
No full textlingI was interested at finding on the shore a ling, or fresh water cod, of sixteen inches.PRINTED ITEM G.M.Story June 1963Not usedNot usedWithdrawnChecked by Jordyn Hughes on Fri 12 Jun 201
AAC Ling Barley
No full textAAC Ling is a two-row spring feed barley (Hordeum vulgare L.) cultivar with high grain yield, high straw yield, and good lodging resistance. It was tested as CH2720-5 in the Atlantic Recommending Committee for Cereal Crops (2015–2017), Quebec Recommending Committee for Cereal (2015–2017), and Ontario Cereal Crops Committee (2016–2017) trials before being registered by the Canadian Food Inspection Agency in 2018. AAC Ling was developed by the Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON. AAC Ling is recommended for barley growing areas in eastern Canada.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
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[Sue Young, Lisa Ling, and Dan Emenheiser]
No full textA photograph of people gathered at a reception during the Women of Color Conference. They are (L-R) Sue Young, Lisa Ling, and Dan Emenheiser. Ling spoke during the conference
Ling
No full textlingOn our way we picked up a dead fish I never saw before. Leslie says it is a Ling. It is much like a Tomcod, but has a somewhat flattened head, and a very narrow tapering tail.GMS Feb 76Not usedNot usedWithdrawnChecked by Jordyn Hughes on Fri 12 Jun 201
The drivers of China’s regional carbon emission change—a structural decomposition analysis from 1997 to 2007
No full textUsing three official multiregional input–output tables and carbon emission data, we decompose the change in carbon emission for eight regions of China between 1997 and 2007. We do so according to the following seven partial effects: (i) Changes in energy end-use structure, (ii) effect of energy intensity, (iii) the added value’s share of gross output, (iv) changes in sub-industry structure, (v) changes in the substitution of import for intermediate inputs, and changes in (vi) structure and (vii) level of final demand. We find energy intensity contributes most to CO2 abatement throughout China, while other factors vary widely across the different regions. We suggest that governments consider regional disparity and CO2 flows when formulating policies; structural change with an eye toward energy-savings and general efficiency improvements, like better insulated buildings, are among measures we deem effective.Peer reviewe
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[Group gathered around Lisa Ling]
No full textA photograph of people gathered during the Women of Color Conference. They are (L-R) David Hall, Samantha Weber, Lisa Ling, and Dan Emenheiser. A waiter is carrying a platter of what appears to be white wine
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