Quantifying the spatial implications of future land use policies in South Africa

Land use policies have a definite and lasting impact on the way that cities grow; however, it is difficult for policy- and decision-makers to observe and quantify the implications of their land use policies and strategies. There is thus a need for information and tools that can adequately support policy debates and influence decision-making through scientific evidence. Land use change models provide such a tool and have often been applied and tested in developed countries but lack the ability to simulate many of the multifaceted social problems observed in developing countries. Some more advanced models also require large amounts of data that are normally not available for South African cities. In this research, we adjust the existing Dyna-CLUE model to accommodate the unique multifaceted problems such as informal settlements, backyard shacks, rapid population growth and government interventions with regard to social housing projects and test the model for the city of Johannesburg. Two scenarios (AS-IS and Policy-Led) in combination with an urban development boundary (UDB) were tested and their effect was evaluated based on their influences on the cities spatial inequality, densification of the urban spatial pattern and increase in access to public transport. Results indicated that the Policy-Led scenario can improve the wealth and economic distributions between the north and south of the city. It can also provide more economic opportunities for the households living in the south of the city. Enforcing an UDB has a positive impact on urban sprawl and will result in increased densities across the city. The effect of the policies on the commuter distances indicated that both scenarios will lead to an overall increase in the number of households that have access to public transport, but the Policy-Led scenario will allow a greater number of low-income earners to have access to the public transport systems. We see great possibilities for using the existing model to simulate land use change in South African cities. The model requires less input data compared to some other modelling techniques and with small adjustments and adaptations can prove to be a useful tool for urban planner

LEPRASIM, an Agent-Based Model to simulate leprosy in Indonesia

Despite continuous efforts, leprosy persists locally in endemic areas including Indonesia. A cost effective method to interrupt leprosy transmission is needed to eradicate the disease completely. Agent-based Simulation models can provide a better insight in the spatio-temporal diffusion patterns of a disease, but can also be used to investigate different intervention strategies. We developed an agent-based model (LEPRASIM) to test a number of possible future long-term prevention strategies on their effectiveness. The model is applied to a case study on a group of five islands in the Flores Sea, Indonesia. Empirical data on leprosy incidence and prevalence are available for these islands as a result of a chemoprophylaxis intervention study during the period 2000-2010. The long-term effectiveness (2000-2025) of a set of eight leprosy prevention strategies, aimed at different contact groups of symptomatic patients is measured. Tests on long-term leprosy prevention strategy for the contact groups of leprosy patients using rifampicin prophylaxis revealed that the effectiveness depends on the prevalence rate. At low prevalence rate an approach aimed at household and neighbour contacts proofed to be the most effective. At high prevalence rates a blanket approach, followed by a targeted approach aimed at both household and neighbour contacts of infected individuals is the most effective option. In this study we show how Agent-based Simulation can be an effective tool for testing long term intervention strategies. The major advantage of the agent-based approach is that social contacts can be modelled directly and that the model is spatial, taking into account the distribution of people over the different islands. Although the model was developed for a specific case study, it is adjustable for other areas, including new types of social contacts and prevention strategies

Space Education with The Living Textbook, A web-based tool using a Concept Browser

The ability to recognize the relationships between concepts is a crucial aspect of meaningful learning. Expert-generated concept maps have been shown to help students in forging connections by acting as scaffolds for cognitive processing. The Faculty of Geo-Information Science and Earth Observation (ITC) of the University of Twente is developing a Living Textbook which combines an online knowledge repository with an interactive map visualizing the relationships between concepts. Our teachers and students have started to use this in the core modules at the start of our MSc programme. Tests show that this is a promising approach that drives us to further develop its procedures and applications