Jochem Liem

Who am I?

I am a PhD student at the Human Computer Studies of the University of Amsterdam. My thesis about supporting knowledge construction through qualitative modelling, which should be finished beginning 2010. Half of my time I am working on the DynaLearn FP7 EU project. During my PhD I worked on the the Naturnet-Redime project.

DynaLearn

This project aims to revolutionize the teaching of the hard sciences. Technology, teaching and environmental science domain experts join their expertise to create a teaching environment. This environment allows learners to create meaningful representations of scientific knowledge (in Qualitative Models), has virtual characters to interact with the student to explain modelling issues and guides the learner through the teaching material. Furthermore, the project aims to establish a library of environmental science knowledge through Semantic Web technology. This repository contains models made by domain experts and models uploaded by students. The virtual characters will use this repository as a knowledge base. The learning environment will be co-designed and evaluated by teaching experts.

NaturNet-Redime

NaturNet Redime aims to improve the understanding and to provide education concerning all aspects of Sustainable Development. Part of this project focusses on learning through modelling and simulation using Qualitative Reasoning (QR) technology. I am part of the team that develops and supports the qualitative reasoning and modelling workbench Garp3 used within the project.

PhD Research (outdated)

My PhD research focusses on supporting qualitative modelling activities. The first part of the project I've focussed on sharing, searching for and reuse of qualitative knowledge models (about sustainable development) using ontologies. Qualitative models have been made machine-accessible by formalising them in the Web Ontology Language (OWL), based on a generic QR vocabulary ontology. OWL import/export functionality has been added to Garp3 to allow users to upload their models to a qualitative model repository on the qualitative reasoning and modelling portal, which allows sharing and searching for models. Model merging functionality has been implemented to allow users to reuse (parts of) shared models. The second part of the project I will focus on supporting model debugging, which is one of the main bottlenecks in the model building process.

Research Interests

Qualitative Reasoning: The aim of qualitative modelling and reasoning is to build conceptual models of systems. The knowledge captured in this approach explicitly represents the common-sense about the system in a way that humans find understandable, so this knowledge can easily be transferred. There is an explicit separation between structural ingredients, which describes the organisation of the system, and the behavioural ingredients, which describe the quantities, values, and the relations between them. One type of these relations are causal dependencies which are used to capture knowledge about the causality between different quantities, i.e. how how quantities affect each other. From complete models the behaviour of systems can be predicted (in the form of state graphs), which describe the transitions from a specific begin situations in the system, through different situations to situations in which no more changes occur. Next to the ability to predict the behaviour of a system, causal dependencies make it possible to provide a causal explanation of why a system behaves in a particular way. These features of qualitative simulation provide support hypothesis testing and learning.
Knowledge Representation and Reasoning: Particularly, common-sense reasoning, patterns, expressiveness, problem solving, tasks.

Research

HCS Colloquia

I organize our HCS group colloquia

Teaching

Personal

How to reach me

Work

Human Computer Studies Group
Informatics Institute
Faculty of Science
University of Amsterdam
Science Park 107, Room F1.01
1098 XG, Amsterdam, The Netherlands

Phone: +31 (0)20 525 6801 (work)
Mobile: +31 (0)6 4321 9992
Fax: +31 (0)20 525 7490 (work)

J.Liem@uva.nl
http://www.science.uva.nl/~jliem/