Modeling the outbreak, spread, and containment of tuberculosis

It seems my interest into disease models is growing. While the development of the cholera model is still underway, over the summer I have had been working with a very talented high school student looking at the outbreak, spread and containment of tuberculosis (TB). Why might you ask? TB is a global problem with 1.8 billion people having a TB Infection, 8.8 million people infected with the TB disease, and around 1.5 million annual deaths. It is the second most common form of death from an infectious disease with the majority of cases in developing countries.

So we have been developing a model that explores how TB might manifest itself, spread within an urban setting and the potential to contain the disease. We have chosen as our test case the Kibera slum within Nairobi, Kenya. Agents in this model represent the residents of the Kibera slum. They are mobile and goal-orientated, seeking to fulfill one goal before moving on to the next. Goals are determined based on the agent’s characteristics (age, sex, etc.) as well as their needs (water, food, health etc.). The exact location they choose to go to is also affected by the distance. When agents interact with one another, they can be infected with TB. Infection is determined upon the amount of bacilli absorbed by agents and their immune response. The transition from infection to disease for HIV positive patients is also dependent on the patient’s CD4 cell count.  What you see below is a poster we presented at Krasnow Institute Retreat.

To give a sense of the dynamics of the model, the movie below shows agents moving around the slum and how their health status changes as time progresses.

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Census Atlas Japan

The 2011 Census Open Atlas project has been put on hold recently as various other research projects have intervened – more on these soon. However, over the summer  Chris Brunsdon and I have taken a research trip to Ritsumeikan University (Japan) where we visited Keiji Yano and Tomoki Nakaya. As part of this trip I began developing a census atlas for […]

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‘Keeping the spirit alive’ – preservations of participatory GIS values in the Geoweb

During the symposium “The Future of PGIS: Learning from Practice?” which was held at ITC-University of Twente, 26 June 2013, I gave a talk titled ‘Keeping the spirit alive’ – preservations of participatory GIS values in the Geoweb, which explored what was are the important values in participatory GIS and how they translate to the […]

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Kindle Maps and E Ink properties

CHI 2013 and GeoHCI workshop highlighted to me the importance of understanding media for maps. During CHI, the ‘Paper Tab’ demonstration used E-Ink displays to demonstrate multiple displays interaction. I found the interactions non-intuitive and not mapping very well to what you would expect to do with paper, so a source for confusion – especially […]

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UCL Live Campus Augmented Reality App – Created by Masters Students at CASA

UCLive is an Augmented Reality Map of UCL developed by students on the Masters in Advanced Spatial Analysis and Visualisation at CASA. Featuring live data, the augmented reality android app works by simply pointing your mobile device at any of the UCL maps across campus. Running in Unity and mixing a number of GIS and…

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New Publication: GIS and Agent-Based models for Humanitarian Assistance

Inputs to the model
 
As the readers of the blog know, we have an interest in GIS, agent-based modeling and crowdsourcing. Now we have a paper that combines all these three elements. Its entitled “GIS and Agent-Based models for Humanitarian Assistance” and is published in Computers, Environment and Urban Systems. 
 
The model itself was written in MASON and uses extensively GeoMASON. Data comes from several different sources (both raster and vector) including OpenStreetMap and LandScan. Below you can read an abstract of the paper and see a movie of one of the scenarios.

“Natural disasters such as earthquakes and tsunamis occur all over the world, altering the physical landscape and often severely disrupting people’s daily lives. Recently researchers’ attention has focused on using crowds of volunteers to help map the damaged infrastructure and devastation caused by natural disasters, such as those in Haiti and Pakistan. This data is extremely useful, as it is allows us to assess damage and thus aid the distribution of relief, but it tells us little about how the people in such areas will react to the devastation. This paper demonstrates a prototype spatially explicit agent-based model, created using crowdsourced geographic information and other sources of publicly available data, which can be used to study the aftermath of a catastrophic event. The specific case modelled here is the Haiti earthquake of January 2010. Crowdsourced data is used to build the initial populations of people affected by the event, to construct their environment, and to set their needs based on the damage to buildings. We explore how people react to the distribution of aid, as well as how rumours relating to aid availability propagate through the population. Such a model could potentially provide a link between socio-cultural information about the people affected and the relevant humanitarian relief organizations.”

Full Reference: 

Crooks, A.T. and Wise, S. (2013), GIS and Agent-Based models for Humanitarian Assistance, Computers, Environment and Urban Systems, 41: 100-111.

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New Publication: GIS and Agent-Based models for Humanitarian Assistance

Inputs to the model
 
As the readers of the blog know, we have an interest in GIS, agent-based modeling and crowdsourcing. Now we have a paper that combines all these three elements. Its entitled “GIS and Agent-Based models for Humanitarian Assistance” and is published in Computers, Environment and Urban Systems. 
 
The model itself was written in MASON and uses extensively GeoMASON. Data comes from several different sources (both raster and vector) including OpenStreetMap and LandScan. Below you can read an abstract of the paper and see a movie of one of the scenarios.

“Natural disasters such as earthquakes and tsunamis occur all over the world, altering the physical landscape and often severely disrupting people’s daily lives. Recently researchers’ attention has focused on using crowds of volunteers to help map the damaged infrastructure and devastation caused by natural disasters, such as those in Haiti and Pakistan. This data is extremely useful, as it is allows us to assess damage and thus aid the distribution of relief, but it tells us little about how the people in such areas will react to the devastation. This paper demonstrates a prototype spatially explicit agent-based model, created using crowdsourced geographic information and other sources of publicly available data, which can be used to study the aftermath of a catastrophic event. The specific case modelled here is the Haiti earthquake of January 2010. Crowdsourced data is used to build the initial populations of people affected by the event, to construct their environment, and to set their needs based on the damage to buildings. We explore how people react to the distribution of aid, as well as how rumours relating to aid availability propagate through the population. Such a model could potentially provide a link between socio-cultural information about the people affected and the relevant humanitarian relief organizations.”

Full Reference: 

Crooks, A.T. and Wise, S. (2013), GIS and Agent-Based models for Humanitarian Assistance, Computers, Environment and Urban Systems, 41: 100-111.

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A Survey of the use of Geographic Information Systems in English Local Authority Impact Assessments.

Across the public sector, Geographic Information Systems (GIS) and spatial analysis are increasingly ubiquitous when making decisions involving people and places. However, historically GIS has not been prevalently applied to the various types of impact assessment. As such, this paper presents findings from a survey conducted in 2011 of 100 local authorities in England to […]

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Transactions of the Institute of British Geographers vritual issue on GIScience

Since early 2010, I had the privilege of being a member of the editorial board of the journal Transactions of the Institute of British Geographers . It is a fascinating position, as the journal covers a wide range of topics in geography, and is also recognised as one of the top journals in the field […]

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New paper: Agent-based modeling for community resource management: Acequia-based agriculture

We have just got a paper accepted in Computers, Environment and Urban Systems entitled “Agent-based modeling for community resource management: Acequia-based agriculture.” In the paper we explore the complex social interactions of water management, which involves landowners collectively maintaining and managing ditches which distribute water among the properties.

This system of the physical ditches and the maintaining organization together is known as an acequia, and the landowners who maintain it are called Parciantes. Acequias are interesting to researchers because of the developed common property regimes they require to function. The water carried by the ditches is a shared resource, and the complex management system of the acequia has evolved to avoid Hardin’s tragedy of the commons with regard to natural resources in the sense that it prevents the resource from being overused or under-maintained to the detriment of everyone. Ostrom has extensively studied the process of sharing such resources, investigating the structures set in place to preserve them. In ‘‘Governing the Commons’’, her book on common pool resources and human–ecosystem interactions, she suggests a set of characteristics that define stable communal social mechanisms. These characteristics include the presence of environment-appropriate rules governing the use of collective goods and the efficacy of individuals in the system.

Below is the abstract from the paper:

Water management is a major concern across the world. From northern China to the Middle East to Africa to the United States, growing populations can stress local water resources as they demand more water for both direct consumption and agriculture. Irrigation based agriculture draws especially heavily on these resources and usually cannot survive without them; however, irrigation systems must be maintained, a task individual agriculturalists cannot bear alone. We have constructed an agent-based model to investigate the significant interaction and cumulative impact of the physical water system, local social and institutional structures which regulate water use, and the real estate market on the sustainability of traditional farming as a lifestyle in the northern New Mexico area. The regional term for the coupled social organization and physical system of irrigation is ‘‘acequias’’. The results of the model show that depending on the future patterns of weather and government regulations, acequia-based farming may continue at near current rates, shrink significantly but continue to exist, or disappear altogether.
In the figure below we show some of our efforts in verification of the model, specifically, the water network, after 100 years of regular maintenance (A) and after 100 years of no maintenance (B). The darker the line, the more clear the segment is of sedimentation; only unmaintained acequias are impacted by sedimentation in this model, and appear in lighter shades.

Below is a movie are a few sample model runs showing how different scenarios play out, specifically with respect to land-use change.

Full reference:

Wise, S. and Crooks, A. T. (2012), Agent Based Modelling and GIS for Community Resource Management: Acequia-based Agriculture, Computers, Environment and Urban Systems. Doi http://dx.doi.org/10.1016/j.compenvurbsys.2012.08.004.
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New paper: Agent-based modeling for community resource management: Acequia-based agriculture

We have just got a paper accepted in Computers, Environment and Urban Systems entitled “Agent-based modeling for community resource management: Acequia-based agriculture.” In the paper we explore the complex social interactions of water management, which involves landowners collectively maintaining and managing ditches which distribute water among the properties.

This system of the physical ditches and the maintaining organization together is known as an acequia, and the landowners who maintain it are called Parciantes. Acequias are interesting to researchers because of the developed common property regimes they require to function. The water carried by the ditches is a shared resource, and the complex management system of the acequia has evolved to avoid Hardin’s tragedy of the commons with regard to natural resources in the sense that it prevents the resource from being overused or under-maintained to the detriment of everyone. Ostrom has extensively studied the process of sharing such resources, investigating the structures set in place to preserve them. In ‘‘Governing the Commons’’, her book on common pool resources and human–ecosystem interactions, she suggests a set of characteristics that define stable communal social mechanisms. These characteristics include the presence of environment-appropriate rules governing the use of collective goods and the efficacy of individuals in the system.

Below is the abstract from the paper:

Water management is a major concern across the world. From northern China to the Middle East to Africa to the United States, growing populations can stress local water resources as they demand more water for both direct consumption and agriculture. Irrigation based agriculture draws especially heavily on these resources and usually cannot survive without them; however, irrigation systems must be maintained, a task individual agriculturalists cannot bear alone. We have constructed an agent-based model to investigate the significant interaction and cumulative impact of the physical water system, local social and institutional structures which regulate water use, and the real estate market on the sustainability of traditional farming as a lifestyle in the northern New Mexico area. The regional term for the coupled social organization and physical system of irrigation is ‘‘acequias’’. The results of the model show that depending on the future patterns of weather and government regulations, acequia-based farming may continue at near current rates, shrink significantly but continue to exist, or disappear altogether.
In the figure below we show some of our efforts in verification of the model, specifically, the water network, after 100 years of regular maintenance (A) and after 100 years of no maintenance (B). The darker the line, the more clear the segment is of sedimentation; only unmaintained acequias are impacted by sedimentation in this model, and appear in lighter shades.

Below is a movie are a few sample model runs showing how different scenarios play out, specifically with respect to land-use change.

Full reference:

Wise, S. and Crooks, A. T. (2012), Agent Based Modelling and GIS for Community Resource Management: Acequia-based Agriculture, Computers, Environment and Urban Systems. Doi http://dx.doi.org/10.1016/j.compenvurbsys.2012.08.004.
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Picking Up Raster GIS Skills

Do you need to work with satellite images or datasets that are gridded? By gridded I mean data that are stored in grid like cells such as heights of the earth (or a digital elevation model), a global land cover map or gridded populations of the world? There are many other gridded datasets available, e.g. … Read more

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Using the OSTN02 transformation in PostGIS

When converting coordinates between WGS84 (GPS) and OSGB36 (UK National Grid), using OSTN02 can gain us a few metres in accuracy over the basic parametric transformation provided by PostGIS’s st_transform via PROJ.4. Happily, Ordnance Survey now distribute an NTv2 version of the OSTN02 transformation, courtesy of the Defence Geographic Centre, which can be used by […]

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