"The growing availability of data on the Web provided by Web 2.0 applications and, more recently through Linked Data, brought the computational pattern expressed as ETL to reemerge in a scenario with additional complexity, where the number of data sources and the data heterogeneity that needs to be supported by ETL drastically increases. In this scenario, issues with data quality and trustworthiness may strongly impact the data utility for end-users.

Combined Nomenclature

"The Combined Nomenclature is the goods classification used within the EU for the purposes of foreign trade statistics. It is also used by Directorate General 'Taxation and Customs Union' of the European Commission for customs duty purposes. The classification is maintained by Eurostat for the statistical aspects and by Taxation and Customs Union DG for the tariff aspects. The classification is based on the Harmonized System (HS) which it sub-divides where necessary for purposes of external trade, agricultural regulation and customs duties.

AlgaeBase Taxonomy

"You can browse though the hierarchy by clicking on the names below and drilling down. At each level the numbers of current species are given for each taxon. Only currently accepted names are currently included. Should you find any errors, please click on the little envelope icon, and you can send me an e-mail via the site. In order to make calculations of the numbers of species of living algae, note that 68 or so species of flowering plants (seagrasses) are included for the present (under the Phylum Magnoliophyta), and about 2000 fossil algae, mainly calcium- and silica- secreting forms.

Classification of Environmental Protection Activities and Expenditure

"CEPA is a functional classification used to classifiy activities, products, outlays and other transactions whose primary purpose is environmental protection. It is a hierarchic classification with 3 levels (level 1: 9 categories, level 2: 46 categories, level 3: 20 categories)."

CSO Standard Fields of Education Classification

"The CSO Standard Fields of Education Classification is a classification of the various fields of study which can be undertaken. This classification was derived from a joint project with Eurostat and UNESCO. It is based on the International Standard Classification of Education - ISCED 1997 (Fields of Education). In 1999, Eurostat and UNESCO further elaborated on the ISCED 1997 and provided a third level of about 80 categories called 'Detailed Fields'.

Activity Coding List for Harmonised European Time Use Surveys

"The Harmonised European Time Use (HETUS) activity coding list is based on international practices and previous classifications of daily activities used in Europe. The coding system and index were tested and revised on the basis of time use pilot surveys in 18 countries. The final system was completed in 2000 and revised in 2008. The European activity coding list allows several groupings of activities depending on the purpose of the analysis."