knowledge based systems

Protégé 4.1 with JVM7

Problem description:
The problem occurs as Protégé 4.1 was build and working with Java version.
If you use version >6, like on up-to-date systems than you have to modify some things.

1. Rename \bin\felix.jar to something e.g. felix.jar.Backup
2. Download latest Felix Framework from :
3. Extract the zip and look for the file : “felix.jar”
a. in my case under : \felix-framework-4.0.3 \bin\
4. Copy the felix.jar file into the \bin\
5. Start Protégé and be satisfied and happy ;)
If problems occur you always have the backup felix file to revert to the standard installation.

Helpful Sites:

Running Protégé 4.1 with JVM6


Problem description:
The problem occurs as Protégé 4.1 was build and working with Java version.
If you use version >6, like on up-to-date systems than you have to modify some things.

• Having also JVM (version 6) installed on your computer.

1. Choose when downloading Protégé 4.1, download without JVM
2. When running the installer you have to choose a JVM at some point
3. Instead of choosing the up-to-date Java 1.7 choose instead Java 1.6 runtime
4. Run the application, be happy ;)

Installing and Running Protégé 4.1

Description Protégé is an environment for creating and editing ontologies and knowledge bases. In KBS (Knowledge Based Systems) we were supposed to use version: Protégé 4.1. After installing it I kept getting the same error message (also included picture in attachment): <code> C:\Program Files\Protege_4.1>java -Dlog4j.configuration=file:log4j.xml -DentityExpansionLimit=100000000 -Dfile.encoding=utf-8 -Dorg.protege.plugin.dir=plugins -classpath bin/felix.jar;bin/ProtegeLauncher.jar org.protege.osgi.framework.Launcher Core Bundle 1 failed to start. Exception in thread "main" org.osgi.framework.BundleException: Unresolved constraint in bundle org.protege.common [1]: package; (&(package=javax.swing.text)(version>=0.0.0)) at org.apache.felix.framework.Felix.resolveBundle( at org.apache.felix.framework.Felix.startBundle( at org.apache.felix.framework.BundleImpl.start( at org.apache.felix.framework.BundleImpl.start( at org.protege.osgi.framework.Launcher.startBundles( at org.protege.osgi.framework.Launcher.start( at org.protege.osgi.framework.Launcher.main( </code> Why does this error occur? How can I make Protégé 4.1 run?

Web Browser Protege

This link describes how to install Protege Web Browser, a Java-based Web application that allows you to share, browse, and do some basic editing of Protege knowledge bases via the World Wide Web. 

What's a proper programming language for Semantic Web reasoning?

As I already mentioned, the internet is one big database. But how much is the information worth? Obviously not all the information on the internet is true and not all information is worth to be taken into consideration by solving problems. As I see it, the Semantic Web is still in its child shoes. New technologies and ideas come up, each and every day. The progress of structuring date using W3C recommendations has just begun. That allows to make more and more data being read- and understoodable by machines. But in the end, intelligent software (e.g. agents) has to do some kind of reasoning to solve their given problems. The software has to decide on its own, which information is worth to be taken into consideration and which information isn't. Moreover, the software has to decide how to use the given data. Logic Programming is one way to go. Lot's of (semantic web related) artificial intelligent and search problems could be solved by Logic Programming technologies such as Answer Set Programming (ASP). The simpleness and elegancy of ASP may perfectly fit to Semantic Web tasks, such as information collection and interpretation from standardized Semantic Web knowledge bases or intelligent software design. Does there already exist some languages that fulfills this description? Does there exist logic programming languages that are able to be used with modern Semantic Web technologies, such as XML, RDF and OWL? Yes it does.....
Subscribe to knowledge based systems