ESciDoc Logical Data Model/Item

Introduction[edit]

This page provides general overview on the Item resources within the eSciDoc repository. General introduction available at eSciDoc Logical Data Model page.

Model description[edit]

An Item represents minimal unit of content managed in the eSciDoc repository. Each Item comprises of:
- at least one MetadataRecord i.e. one or more metadata descriptions of the overall content of the item
- zero or more Component - the actual (or externally referenced) content and at least one metadata description

eSciDoc data model additionally defines the concept of a SurrogateItem as a "proxy" object to a resource which can reside in or outside the eSciDoc repository. See also SurrogateItem for more details.

UML Diagram[edit]

For simplicity reasons properties of the objects are not represented on the diagram. Properties are managed by the escidoc repository itself and may change during time. For more information on the properties and ther usage please check the documentation available at eSciDoc Item Service.

Implementation[edit]

Item resources are managed by the ItemService of the eSciDoc core infrastructure. See eSciDoc Item Service for more information.

Examples[edit]

Publication items[edit]

An Item object is an Article published in a journal
- MetadataRecord: contains the bibliographic metadata (title, author, publication type e.g. journal article, author affiliation, year of publication, etc.) structured accordingly a particular metadata profile
- Component1:one published version of the fulltext of the article
  - Component1.MetadataRecord1: title, description of the full-text, reference to the license
  - Component1.MetadataRecord2: technical metadata of the file (e.g. generated from JHove)
  - Component1.Content: the actual bytestream e.g. PDF or reference(link) to the content external to the repository
- Component2:supplementary material e.g. data on results provided in the fulltext of the article
  - Component2.MetadataRecord1: title, description of the file
  - Component2.MetadataRecord2: technical metadata of the file (e.g. generated from JHove)
  - Component2.Content: the actual file or reference(link) to the content external to the repository
- Instances with actual content:
  - Publication item presented
  - Publication item in the repository
- Instances with referenced content:
  - Publication item presented
  - Publication item in the repository

Face items[edit]

An Item object is an image of a facial expression, showing emotions such as: happiness, anger, saddness etc.. Each item contains two sets of image captions of the expression (each face/expression was captured twice). Sets are named "a" for the first image caption and "b" for the second caption.
- MetadataRecord:contains metadata of the face and expression such as: gender, age, emotion, age-group
- Component1: an image that captures the facial expression
  - Component1.MetadataRecord1: contains information on the image caption set; type of the image such as: original resolution, thumbnail or web resolution.
  - Component1.MetadataRecord2: technical metadata of the image (e.g. generated from JHove)
  - Component1.Content: the actual bytestream e.g. JPEG file itself
- Component2: an image that captures the facial expression
  - Component2.MetadataRecord1: contains information on the image caption set; type of the image such as: thumbnail
  - Component1.MetadataRecord2: technical metadata of the image (e.g. generated from JHove)
  - Component1.Content: the actual bytestream e.g. JPEG file itself
- Instances:
  - Face item presented
  - Face item in the repository