====== Introduction to SemWeb Project 2016: Semantic Wiki Loki ======

This is a short introduction to Semantic Wiki [[http://loki.ia.agh.edu.pl/wiki/start|Loki]]. There is no report after this lab, but it is important to know how wiki works because we will be using it during the project :-)
==== - Loki - Introduction ====
  - Loki is a Semantic Wiki. Semantic Wiki is a [[wp>wiki|wiki]] system with an underlying model of knowledge. To make it simple: Loki is a wiki with a possibility to add specific RDF triples to the wiki pages. This lab will present main Loki concepts.
  - Let's start with the [[http://loki.ia.agh.edu.pl/wiki/docs:loki-about|Loki about]] page to get to know the system better (you can omit the "Rule-based Reasoning" section).
  - Loki manuals are placed here: [[http://loki.ia.agh.edu.pl/wiki/docs:loki-tutorial|Loki Tutorial]] and [[http://loki.ia.agh.edu.pl/wiki/docs:userman|Loki User manual]]. You can leave them open and refer to them if you will get into troubles. 
==== - Page edition ====

  - With your //username and password// log in to [[http://loki.ia.agh.edu.pl/ckexp/semweb2016/|SemWeb 2016 Loki installation]].
  - Create a page <code>http://loki.ia.agh.edu.pl/ckexp/semweb2016/users:<your-login></code> e.g. <code>http://loki.ia.agh.edu.pl/ckexp/semweb2016/users:kkutt</code>
    - Enter the link to the navigation bar
    - If the page doesn't exist (and it shouldn't exist yet ;-) ) click ''edit this page'' and shortly describe yourself, e.g. <code>
My name is Example student. I am 12 years old.
Currently I study at AGH-UST, faculty of <enter here the full name of the faculty>.
I am interested in math and philosophy.

Now, I am sitting next to: Student X and Student Z.
</code>
  - Save the page:
    * At the bottom you can see the form like this on the figure: \\ {{http://loki.ia.agh.edu.pl/wiki/_media/docs:prov-forms.png}}
    * **URIs/URLs for used resources (put one URI in one line)** field (red frame on figure) -- here enter all URIs that you have used during current page edition; e.g. now it could be <code>http://www.agh.edu.pl/en/agh-ust-faculties/</code> if you were looking for the full faculty name,
    * if your edition is based on other page from the wiki (e.g. you have used the <code>http://loki.ia.agh.edu.pl/ckexp/semweb2016/users:kkutt</code> to get the name of the man next to you) you can enter this URI as other pages or you can simply select it (and double-click on it) from the second field (green frame); this page will appear in the left field with the ''lokipage:'' prefix (''lokipage:'' is the prefix for ''http://loki.ia.agh.edu.pl/ckexp/semweb2016/''),
      * if there are a lot of pages in your wiki, you can use a filter field (blue frame).
    * There is also 'Edit summary' field (black frame) for comments about changes in wiki page.
==== - Categories ====
  - Let's do some RDF triples!
  - In Loki the subject (the first element in the triple) is the page that you are editing. So, if you are putting an annotation on ''<nowiki>http://loki.ia.agh.edu.pl/ckexp/semweb2016/users:kkutt</nowiki>'' page, this will the URI of the subject for all triples.
  - Firstly we can state that we are users:
    - in RDF it looks like that: <code>http://loki.ia.agh.edu.pl/ckexp/semweb2016/users:kkutt   rdf:type   <User>.</code>
    - the equivalent in the Loki is ''User'' **category**.
    - Based on the [[http://loki.ia.agh.edu.pl/wiki/docs:userman|User manual]], add your page to the **User** category.
==== - Properties ====
  - Based on the [[http://loki.ia.agh.edu.pl/wiki/docs:userman|User manual]], annotate the content of your //User// page so that it contains the following semantic information about you:
    * Name (first + last name)
    * Age
    * People that are sitting next to you
    * You favourite subject on EIS during current term (use one of three names: ''BIM'', ''Rules'', ''SemWeb'')
==== - Inline queries ====
  - Read the manual section on [[http://loki.ia.agh.edu.pl/wiki/docs:userman#searching_interfaces|ASK queries]].
  - Using the **ASK queries** add to your page the list of the users whose favourite subject is the same as yours
    - Format the output of the query as unordered list
  - Build another query listing the users with the same favourite subject:
    - Display it as a table
    - Sort by age.
    - Define a default value if a query returns no value.

==== - Semantic Web Standards ====
  - Read the [[http://loki.ia.agh.edu.pl/wiki/docs:userman#sparql_queries|manual section on SPARQL]].
  - On your page, build 3 example SPARQL queries which asks for specific kinds of information about other users (you decide what criteria to use in the query!).
    - SELECT query
    - ASK query
    - DESCRIBE query
  - Observe the results.
  - There is also a possibility to ask these queries using SPARQL Endpoint: http://loki.ia.agh.edu.pl/ckexp/semweb2016/sparql/. Try them there.
  - Read the [[http://loki.ia.agh.edu.pl/wiki/docs:userman#export_to_rdf|manual section on RDF export]].
  - Export your page. Analyze the exported file. Find the category, relations and attributes that you entered - how are they represented?
==== - Reasoning ====
In Loki it is possible to embed Prolog code within ''<nowiki><pl>...</pl></nowiki>'' tags. E.g. using Prolog code we can create a set of custom recommendations, e.g. in wiki with movies: "Movies, where the leading lady is X and the movie was made before 1940" or in wiki with countries: "City which is located in a country which is by a sea and is not listed as a member of the EU".
  - Read the [[http://loki.ia.agh.edu.pl/wiki/docs:plwiki1api|PlWiki 1.0 - Plugin API]], section on Prolog.
  - On your **user** page create a section ''Specific users''
  - Create a Prolog goal to select users according to some criteria (it's up to you). Optionally, you can define some interesting users with a Prolog rule and use it directly in the goal.
  - If you encounter problems, use the [[http://loki.ia.agh.edu.pl/wiki/docs:userman#debug_functions|debug functionality]] of Loki.

==== - Ontology inside Loki ====

  - In current version of Loki, ontology will be placed in the ''special:ontologies:'' namespace (main ontology will be available at ''special:ontologies:default''). Your instructor will show you how it works when it will be useful.
  - There is no tool that will check if we are inserting annotations accordingly to the ontology, so we will do this by hand.