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What are metadata?

Metadata are structured data describing resources or publications and contain information on e.g. their content, structure, or form. More abstractly, metadata are descriptions of data, or data about data. Bibliographic data sets and catalogue records in library catalogues are a form of metadata.

The basis for the metadata in OPUS is the Dublin Core Metadata Element Set (short: Dublin Core, or DC) consisting of fifteen basic elements. You may find a reference description here: http://www.dublincore.org/documents/dces/.

Dublin Core is the result of international efforts of libraries, archives, museums, and many other actors being concerned with metadata management to establish a collective consensus in describing electronic objects. Dublin Core is internationally standardized as ISO standard 15863.

For the further processing and retrieval of the metadata it is important to put the information into the correct input field. A field called "title" must contain the name or title of a resource, not the author or an abstract. So we ask you to describe your publication as precisely as possible with the available input fields.

Single elements of the application form

1.  Title

Title of the document or the object.

Definition: The name of the ressource given by the author, the publisher or the creator.

Application reference: obligatory meta-element.

Dissertations need to be specified with a German and an English title. If the dissertation is written in another language, the title has to be specified in all three languages.

2.1 Creator

Name of the author

Definition: The person(s) who are/(is) responsible for the intellectual content. For instance authors (text documents), artists, photographers or illustrators (graphical documents).

For persons, the normed diction "family name, first name"is obligatory, in order to improve searchability of the document. Please do not mention academic titles.

Application reference: When possible (e.g. for diploma thesis or thesis) this is an obligatory element.

2.2 Creator (Urheber)

Name of the organisation

Definition: Organisation(s) which are responsible for the intellectual content of the document. As a rule organisation(s) (in librarian terms: corporate bodies) are responsible for the intellectual content, if there is an author collective or no persons are mentioned as creators in the document (e.g. in examination regulations). The field "Creator" therefore is not necessarily to be filled automatically with the own institute or facuIty. There are seperate fields for this purpose (university, faculty).

Application reference: If possible, this is an obligatory meta element

3.1 Contributor

Name of a person or an organisation.

Definition: Additional persons or organisations to the ones specified in the field creator. They should have contributed a meaningful intellectual feature to the ressource, which is secondary in relation to publisher and creator (e.g. co-author, translator, illustrators...)

For persons´ names the normed diction "family name, first name" is obligatory in order to increase searchability.

3.2 Advisor

The main tutor has to be specified concerning dissertations. Academic titles may be added optionally. (e.g. Muster, Hans Prof.Dr.)

Application reference: No obligatory but desirable meta element in the case that more persons participated in different functions in creating the document. (Exceptions: Specifying the main tutor concerning dissertations is obligatory)

4.1 Controlled keywords (german)

The keywords for controlled description of the document´s content can be automatically taken to the form sheet from the german (SWD) keyword vocabulary.

Application reference: Obligatory meta-element

4.2 Free keywords (german and english)

Additionally there is the possibility to give free keywords when there are no useful keywords in the controlled vocabulary. For better international searchability there is the possibility to give English keywords too.

For dissertations it is necessary to give German and English keywords.

4.3 Classification

As in some cases a verbal description of the content is not adequate, the possibility of classificatory description is offered, when corresponding systems are availabe.

List of available classifications

Application reference: fakultative meta element

5. Short summary

Abstract or free description of the ressource.

Definition: A textual description of the ressource´s content inclusive a short abstract for document ressources. For graphical ressources : Short description of the content. The description need not be longer then 2000 signs. It can be imported from the document through "copy and paste". In the case, that no abstract has been written, the Introduction or the table of content can be used.

For Dissertations it is necessary to give a summary in German and English (independent from the actual language of the dissertation)

Application reference: Obligatory meta element.

6. University - Faculty (Publisher)

Definition: The institution which is responsible that the ressource is at hand. At first, members of the university should bring documents to the library network, which is why the university is entered standardly. Within the university there is arrangement according to faculties.

Application reference: obligatory meta element, which has to be taken from a list.

7.  Year

The year of the document. For dissertation, the date of the oral examination has to be entered as well. For state doctorates, the day of the first public scientific presentation has to be specified. Standard ISO-8601 is used internally.

Publishing date and the last update of meta data is processed automatically by the system.

Application reference: obligatory meta element

8. Resource Type

Definition: Type of publication (e.g. dissertation, diploma-thesis, degree-dissertation, poem, homepage). Controlled vocabulary from a list of accredited terms based on the Dublin Core Standard Object Types is used.

Application reference: obligatory meta element, which has to be taken from a list.

9. Format

Definition: Data technical format of the ressource. Standard entry is application/pdf .

The following formats are availabe at the moment:PDF, PostScript, HTML furthermore the following graphic formats are available: GIF, JPEG etc. .

Dissertationen have to specified in PDF and in original format (e.g. Word, DVI etc.) of the used application (with all used objects like images, graphics, tables etc..).

The entries for this elements provides the necessary informations in order to decide over processing possibilities of the coded data (Hard-and Software to open the ressources (e.g. Acrobat Reader)).

Application reference: obligatory meta-element.

10.  Language

Definition: Language of the intellectual content of the ressource. Internally the NISO Z39.53 standard is used.

Application reference: obligatory meta element which has to be taken from a list.

11. Source

Definition: Printed or electronic source of other publications of the document. For html-coded Shakespeare sonnet this would be the printed version from which the particular electronic sonnet is taken. For a newspaper essay this means (for a conventional publication): Title, Year, Edition, Number and Page numbers and the URL of another electronic version respectively.

Application reference: If it is not the first publication, this is a very desirable meta element.

12. E-mail address

The person delivering the document has to give a contact possibility in order to avoid abuse of unauthorized usage. As a rule, an e-mail address should be specified. To this address the confimration of the entry is sent automatically. As the data is controlled manually, entering a telephone number and a post/institute address is possible respectively.

Application reference: obligatory meta element. Stored temporarily.

13.  Number of files to be uploaded

This is not a Dublin Core Element. In this field the complete number of files to be transmitted on the full text server hast to be specified. At the moment the formats PDF, Post Script, HTML and various graphic formats like GIF, JPEG etc are available.

For example: A HTML file with three images has to be specified as four files.

On the file upload form corresponding fields are offered to enter paths and names of the files on the local computer in order to transfer them to the full text server correctly. At this point, further fields can be use, if the number entered was not correct. For the case that less data is to be transferred then entry fields were specified this is possible without any problems.

Because file names are to be kept, all files should be named relevantly. (e.g. chap01.pdf, chap02.pdf..etc). If the files are numbered, please do this by using two digits.

File names should not contain Umlauts and no space. Instead of space, lines (_) can be used (e.g. chapter_01_introduction.pdf). Ideally, please orientate on ISO 9660-name convention (file names with max. 8 signs, all file names are only allowed to use the letter A to Z (without accents) and the number 0 to 9)

Dissertation have to be transferred as PDF and in original format of the used application (Word, DVI etc). In this case, please do only specify the number of files with one format and not the sum of files in both formats.

Application reference: obligatory element

14.  Period of validity

This is not a Dublin Core Element. Here, limited validity of a document can be entered. After the entered period the document is deleted. As documents are offered over a long term and quotable, this is an exception.

Application reference: obligatory element

Help on GPG-System

1. What's PGP/GPG?

PGP is an acronym for Pretty Good Privacy. It is an (asymetric) encryption-system, which is used to create digital signatures or to encrypt data (e.g. eMails). GPG (Gnu Privacy Guard) uses the same stadard like PGP does, but GPG is in difference to the commercial PGP an open-source-application. Basically PGP and GPG are using a self created key pair, which contains a public and a private key. You can give the public key to others, the private one should be kept secret. The private key is protected with a password, which you have to support when signing or decrypting data.

2. Why do I need a key for publication?

Simplified: because we need to be sure, that the data, which you send us, is really sent by yourself. This is also for your own safety: by signing the data, which you have created, their authenticity is provable and it can be guaranteed, that nobody changes the data without your authorization.

3. Form element key upload

Do you have a PGP or GPG-key already? If you do, please tell us about it by selecting it in the publication form. You will get a form then, in which you can send us your public key by selecting your key file (ending: .asc) in the upload field and click on "Send".
Please sign your files before you upload them using your key.
If we have your key already, it's enough to supply the fingerprint of your key in the form.
If you are not interested in giving us your key and signing your files or you do not have a key just ignore this form and click on "Omit".

4. How can I send you my key?

On the application form there is a page, on which you can support your key file and the corresponding number (fingerprint). Your keyfile must be in ASCII format. The key must contain your real name, the email-address is not regarded by us. We are using the email-address you supplied on the publication form to get in contact with you.

5. What are you doing with my key?

The key is taken into our keyring and is signed with our key. The signature on your key is only used internally.

6. How do I sign my documents digitally?

Please remember the following notes creating your digital signature:
  • Create a separate signature file. Do not attach the signature to the original file!
  • The filename should end with .sig (for binary GPG-signatures and all PGP-signatures) or .asc for clear text signatures (other endings are not accepted)
Example: You want to sign your file dissertation.pdf. You are craeting the signature with your PGP-compliant application and save it in clear ASCII-text file dissertation.pdf.asc (this filename is just an example - you can choose another name if you like it). You are suppliing both files in the upload form. Please remember to upload your public key - we need it to verify your signature.

Here are some tutorials about creating digital signatures using different applications:

7. Creating a signature with PGP for Windows

This manual requires a working installation of PGP for Windows on your system.
  1. Find the file you want to sign in the Windows Explorer or your desktop.
  2. Click with the right mouse key on the file you want to sign
  3. Select in the context menu PGP/Sign
  4. Select the key aou want to use for your signature in the menu on the top (we need the corresponding public key to verify your signature, so please sign the key with the same key you submitted to us - this key has to contain your real name)
  5. Type your passphrasev
  6. Mark "seperate signature" and (optionally) "text output"
Doing so you get a file named like the file you signed with the ending .sig. This is your signature file, which you may upload to us.

8. Creating a signature with GPG für Windows (via WinPT)

This manual requires a working installation of GPG and WinPT (Windows Privacy Tray) on your system and that you have at least one personal key pair.
  1. Click with the right mouse key on the WinPT-Icon in your task bar
  2. Select "File Manager"
  3. Use the file manager to find the file you want to sign (using the menu File/Open...) or drag the file icon from another window or from the desktop and drop it into the File-Manager-Window. You can also put put multiple files into the file manager.
  4. Click on the file you want to sign and select the menu File/Sign
  5. Select the key you want to use for your signature in the menu on the top (we need the corresponding public key to verify your signature, so please sign the key with the same key you submitted to us - this key has to contain your real name)
  6. Mark "Detached Signature" and "Text Output"
Doing so you get a file named like the file you signed with the ending .asc. This is your signature file, which you may upload to us.

9. Creating a signature with GPG via command line

You can use GPG (even on Windows) via command line as well. The commands and parameters are the same on all systems.
For the variable PATH-TO-GPG used in this manual, type the real path on your system, where you have installed gpg (gpg.exe). SIGFILE should be replaced by the file you want to sign.
You can create the signature with the command

If you have more than one private key in your keyring, you have to select the one you want to use for this signature:

The KEY-ID must be replaced with the email-address or the number of the key.

Doing so you get a file named like the file you signed with the ending .asc. This is your signature file, which you may upload to us.