PALO language Home Page
.UNED University

All the material presented in this section has been used for real academic experiences at UNED University

The PALO Language is defined by a set of DTD's that describe different documents, each one to be used for an specific instructional purpose.  These DTD's describe a general template that can be instantiated into an SGML file. In the PALO system, the family of DTD's are known as instructional templates.

PALO files presented here have been translated to XML using James Clark's SP SGML parser. (Using sx command)

The DEMOs presented here have 3 components

  • DTD --> The instructional template describing the tags for the given template. It is a SGML-based DTD
  • PALO File --> The PALO file is an SGML file. It has been translated into an XML file to be editable with Microsoft IE 5.5.  This file is the declarative description of the learning environment according to the instructional template (DTD)
  • DEMO --> The resulting environment after the compilation process of the PALO File using the PALO Compiler.  This environment is an non-interactive web-based scenario to be installed in CD-ROM for demo purposes only. 


Our PALO Compiler tool allow the resulting environment to be delivered in other formats. At this moment, developed at LSI Dept., we have the posibility of creating 3 different web-based environments:

  • A demo environment (the one provided in this page) with no interactivity, but having all the content.
  • An interactive environment using signed java applets. Students can install this environment, and work off-line. From time to time they can connect to our server and send the work done. Actual implementation works with Netscape navigator due to the use of "signtool" to sign the applets. Certificates are "dummy" ones (signed by ourselves) but we considered that enough for our academic purposes.
  • An interactive environment to be used remotely. Users are provided with a password to access the environment and interactivity is provided using dynamic pages using lite/mSQL or php/Oracle

PALO System, DTD's,  XML files and DEMOS have been developed in Spanish. An english translation is on the way at the moment...

The PALO Compiler is to be made freely available with GPL license. Volunteers to test and help in this process, please contact

. DEMO 1  "A Course in Program Verification"
There have been developed 2 documents based in their corresponding instructional template.
  These environments have been in explotation since 99-00 academic year at UNED University
. DEMO 2  " A Chemical environment to support Functional & Organic Analysis"
    There has been developed an instructional template to describe components of a chemical educative environment.

Students are asked to identify an unknown organic compound through a set of tests structured in 5 steps.

  • Chemical Environment (Unknown compound: Aniline) 
  • [DTD]   [PALO file]   [DEMO

    Download the complete learning environment:   DEMO.tar.gz


Miguel R. Artacho  LTCS Group