Agent-based pedestrian modelling

When the focus of interest in geographical systems is at the very fine scale, at the level of streets and buildings for example, movement becomes central to simulations of how spatial activities are used and develop. Recent advances in computing power and the acquisition of fine scale digital data now mean that we are able to attempt to understand and predict such phenomena with the focus in spatial modelling changing to dynamic simulations of the individual and collective behaviour of individual decision-making at such scales. In this Chapter, we develop ideas about how such phenomena can be modelled showing first how randomness and geometry are all important to local movement and how ordered spatial structures emerge from such actions. We focus on developing these ideas for pedestrians showing how random walks constrained by geometry but aided by what agents can see, determine how individuals respond to locational patterns. We illustrate these ideas with three types of example: first for local scale street scenes where congestion and flocking is all important, second for coarser scale shopping centres such as malls where economic preference interferes much more with local geometry, and finally for semi-organised street festivals where management and control by police and related authorities is integral to the way crowds move

Balancing operating revenues and occupied refurbishment costs 1: problems of defining project success factors and selecting site planning methods

In planning the refurbishment of railway stations the spatial needs of the contractor and of the ongoing business stakeholders have to be balanced. A particular concern is the disruptive effect of construction works upon pedestrian movement. RaCMIT (Refurbishment and Customer Movement Integration Tool) was a research project aimed at addressing this problem. The objective of the research was to develop a decision protocol facilitating optimisation of overall project value to the client's business. This paper (the first of two) presents a framework for considering public disruption in occupied refurbishment using two case studies in large railway stations as examples. It briefly describes new tools which (combined with existing techniques) assist decision making in the management of disruption. It links strategic with sitebased decision making and suggests how public disruption may be treated as a variable to be jointly optimised along with traditional criteria such as time, cost and quality. Research observations as well as current literature suggest that for overall decision-making, opportunities may be lost (under current practice) for minimising joint project cost/revenue disruption, and, for spatio-temporal site decision-making, effective and efficient tools now exist to model both sides of the construction site boundary

Drawing the line: balancing the spatial requirements of customer and contractor in occupied refurbishment

In planning the refurbishment of railway stations the spatial needs of the contractor and ofthe ongoing business stakeholders have to be balanced. A particular concern is thedisruptive effect of construction works upon pedestrian movement.RaCMIT (Refurbishment and Customer Movement Integration Tool) is a research projectaimed at addressing this problem through combining the knowledge of the client projectmanager, the construction planner and the pedestrian modelling expert.The objective of the research is to develop a decision protocol (based on problemsencountered in two case studies) facilitating optimisation of overall project value to theclient?s business.Research observations as well as current literature suggest that:? for overall decision-making, opportunities may be lost (under current practice) forminimising joint project cost/revenue disruption and? for spatial decision-making, temporary station configuration during construction(and not just overall pedestrian capacity) is a significant variable for both businessand safety outcomes. In planning the refurbishment of railway stations the spatial needs of the contractor and ofthe ongoing business stakeholders have to be balanced. A particular concern is thedisruptive effect of construction works upon pedestrian movement.RaCMIT (Refurbishment and Customer Movement Integration Tool) is a research projectaimed at addressing this problem through combining the knowledge of the client projectmanager, the construction planner and the pedestrian modelling expert.The objective of the research is to develop a decision protocol (based on problemsencountered in two case studies) facilitating optimisation of overall project value to theclient?s business.Research observations as well as current literature suggest that:? for overall decision-making, opportunities may be lost (under current practice) forminimising joint project cost/revenue disruption and? for spatial decision-making, temporary station configuration during construction(and not just overall pedestrian capacity) is a significant variable for both businessand safety outcomes

Drawing the hoarding line: balancing the spatial requirements of customer and contractor in occupied refurbishment of railway stations

In planning an occupied refurbishment the spatial needs of the contractor and of theongoing business have to be balanced. For the refurbishment of railway stations, aparticular concern to retailers and train operators is the disruptive effect ofconstruction works upon pedestrian movement. RaCMIT (Refurbishment andCustomer Movement Integration Tool) is a research project aimed at investigatingthis problem through concentration on decision criteria/processes of the client andmodels/observations of pedestrian movement. The objective of the research is todevelop a decision protocol and decision support tools, which assist both the clientand the construction planner in addressing these problems and which allows overalloptimisation of project value to the client?s business. The practice of spatial decisionmakingin station refurbishment projects has been investigated in two case studies.This paper concentrates on one case study where pedestrian movement was observedbefore and during the refurbishment. Research observations as well as currentliterature suggest that a) for overall decision-making, opportunities may be lost(under current practice) for minimising joint project cost/revenue (or other)disruption and b) for spatial decision-making, temporary station configuration duringconstruction may be a significant variable. In planning an occupied refurbishment the spatial needs of the contractor and of theongoing business have to be balanced. For the refurbishment of railway stations, aparticular concern to retailers and train operators is the disruptive effect ofconstruction works upon pedestrian movement. RaCMIT (Refurbishment andCustomer Movement Integration Tool) is a research project aimed at investigatingthis problem through concentration on decision criteria/processes of the client andmodels/observations of pedestrian movement. The objective of the research is todevelop a decision protocol and decision support tools, which assist both the clientand the construction planner in addressing these problems and which allows overalloptimisation of project value to the client?s business. The practice of spatial decisionmakingin station refurbishment projects has been investigated in two case studies.This paper concentrates on one case study where pedestrian movement was observedbefore and during the refurbishment. Research observations as well as currentliterature suggest that a) for overall decision-making, opportunities may be lost(under current practice) for minimising joint project cost/revenue (or other)disruption and b) for spatial decision-making, temporary station configuration duringconstruction may be a significant variable

Transport equation with nonlocal velocity in Wasserstein spaces: convergence of numerical schemes

Motivated by pedestrian modelling, we study evolution of measures in the Wasserstein space. In particular, we consider the Cauchy problem for a transport equation, where the velocity field depends on the measure itself. We deal with numerical schemes for this problem and prove convergence of a Lagrangian scheme to the solution, when the discretization parameters approach zero. We also prove convergence of an Eulerian scheme, under more strict hypotheses. Both schemes are discretizations of the push-forward formula defined by the transport equation. As a by-product, we obtain existence and uniqueness of the solution. All the results of convergence are proved with respect to the Wasserstein distance. We also show that $L^1$ spaces are not natural for such equations, since we lose uniqueness of the solution

Pedestrian demand modelling of large cities: an applied example from London

This paper introduces a methodology for the development of city wide pedestrian demand models and shows its application to London. The approach used for modelling is Multiple Regression Analysis of independent variables against the dependent variable of observed pedestrian flows. The test samples were from manual observation studies of average total pedestrian flow per hour on 237 sample sites. The model will provide predicted flow values for all 7,526 street segments in the 25 square kilometres of Central London. It has been independently validated by Transport for London and is being tested against further observation data. The longer term aim is to extend the model to the entire greater London area and to incorporate additional policy levers for use as a transport planning and evaluation tool

City of slums: self-organisation across scales

The city is certainly a fine example of a complex system, where the parts can only be understood through the whole, and the whole is more than the simple sum of the parts. In the present paper we explore the idea that some of these parts are themselves complex systems and the interrelation between complex subsystems with the overall system is a necessary issue to the understanding of the urban complex system. Spontaneous settlements are clear examples of complex subsystems within a complex urban system. Their morphological characteristics combined with their development process are traditionally understood as chaotic and unorganised. And so are Third World cities, traditionally known for their inherent chaotic and discontinuous spatial patterns and rapid and unorganised development process. The paper consists in a brief theoretical analysis developed on the interrelationship between two urban processes across scales: the local process of formation of inner-city squatter settlements and the global process of urban growth. What is the role that spontaneous settlements play in the global dynamics of the city? We explore this issue by analysing experiments of ‘City-of-slums’, an agent-based model that focuses on the process of consolidation of inner-city squatter settlements within a peripherisation process. The paper also includes two previous studies on these topics where the dynamics of these two urban processes are examined as two isolated complex systems and an analysis of the morphological fragmentation of the distribution of spontaneous settlements within the overall city and within the spontaneous settlements themselves. Based on these analyses, we conclude with a brief discussion on the role of self-organisation in the socio-spatial dynamics of Third World cities

Balancing operating revenues and occupied refurbishment costs 2: a Space Syntax approach to locating hoardings

By placing hoardings in publicly accessible areas while carrying out phased occupied refurbishments, a contractor is temporarily redesigning that area. This reconfiguration affects the normal pedestrian flows through such areas. A technique for the analysis of such flows has been developed under a general area of research called Space Syntax. This demonstrates the extent to which visual barriers both constrain and promote pedestrian movement. The main analytical techniques used are Axial analysis and Visibility Graph Analysis which are based upon lines or areas of visibility. Empirical evidence is presented in observations carried out at London Victoria Station before and during a small refurbishment project involving the temporary closure of a single entrance. This evidence is in line with previous Space Syntax studies. The relationship between changes in the station configuration and visitor numbers to retail outlets suggests the need to place hoardings in such a way that both movement and browsing areas remain spatially separated but visually connected. This is also suggested by previous Space Syntax studies and is incorporated into a brief set of general guidelines for clients and contractors to assist the minimisation of disruption to pedestrian movement in publicly accessible areas

The Repast Simulation/Modelling System for Geospatial Simulation

The use of simulation/modelling systems can simplify the implementation of agent-based models. Repast is one of the few simulation/modelling software systems that supports the integration of geospatial data especially that of vector-based geometries. This paper provides details about Repast specifically an overview, including its different development languages available to develop agent-based models. Before describing Repast’s core functionality and how models can be developed within it, specific emphasis will be placed on its ability to represent dynamics and incorporate geographical information. Once these elements of the system have been covered, a diverse list of Agent-Based Modelling (ABM) applications using Repast will be presented with particular emphasis on spatial applications utilizing Repast, in particular, those that utilize geospatial data