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Military Reconstructive Simulation in the Cloud to Aid

Battlefield Excavations

Peter Wittek – University of BorasXavier Rubio-Campillo – Barcelona Supercomputing Centre

Introduction

Agent-Based Modelling is one of the most promising social simulation techniques.Despite its promises, the use of ABM is still limited in Humanities & Social Sciences

Can we improve the methodology using cloud computing?

Reconstructing military engagements

Why do we need to simulate the past?

Agent-Based Modelling of past conflicts

Computational challenges

A case study: improving battlefield archaeology using distributed ABM

Discussion

Classical Agent-Based Modelling

Inspired on SugarScape model

Two key concepts:Agent → individual entityEnvironment → cellular automata

The agent is defined by:Attributes defining its internal stateA “step” method containing predefined rules of behavior

Some issues

Size of simulation: some emergent properties are scale-dependent

Number of simulations?

Complex analysis of simulations:Spatiotemporal patternsVisualization of multivariate statistics

Predefined Behavior

Self-fulfilling prophecy

Rule-based behavior is interesting for simple models, but...

Can we extend them to realistic models?

Can we avoid hand-coded self-fulfilling prophecies?

Is it possible to validate the scientific quality of complicated models?

What about replication?

Goal Oriented Agents

A possible solution is the introduction of advanced AI agents.Can we create goal-orientedagents?Each time step our agents will:

Update knowledgeBuild a model of their environmentConstruct a plan of actions to achieve goals

Goal Oriented Agents

Next step forward...HPC?

These solutions show the need to improve computing resources for scientific social simulations:

a. More executions b. Larger simulations c. Advanced AI agents

a can be easily fixed with several computers executing simulations sequentiallyb & c will need distributed memory architectures:

ClustersCloud ComputingHigh-Performance Computing

The Pandora framework

We need specific utilities to execute a simulation in a distributed environment.Pandora is an open-source C++ framework developed to accomplish this task:

Automatic generation of code for parallel executionCassandra: an ABM visualization toolGIS support (GRASS)Statistical support (R package)

Key concepts: Agent & World

HPC in the cloud

Social science projects should be able to develop computing intensive ABMs even if they don't have access to supercomputers

The use of a cloud-based Beowulf cluster could solve this problem

What if an ABN could be deployed in any Beowulf computer cluster?

Deploying Pandora in the cloud

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A practical case study

Computer simulation of a XVIIIth century battlefield archaeological excavation

Battlefield Archaeology

Archaeologists find the result of concentrating thousands of humans and machines in a small space during a small step of time (1-2 days)The methodology dates from 1970, and is based on the use of metal detectors through a systematic exploration of terrain.It has been modernized by the introduction of Geographical Information Systems and GPS:

Individual tracking of explored routes and remainsSpatial AnalysisGeostatistics

Methodology

Methodology

Questions

Can we distinguish the dynamics of combats?Can we calculate...?

Combat distanceNumber of soldiersDirection of combatResult (advances, retreats...)

In addition, how can archaeological works affect interpretation? Are our hypothesis well based?

To answer these questions we developed an Agent-Based Model of the battle AND the excavation

Visualization: Cassandra

Analysis: R & Grass

Discussion

Agent-Based Models are well suited to generate virtual archaeological records.

The technique requires high computational costs (to model individual behavior and explore parameter space).

Cloud Computing can fulfill these needs if researchers have the correct tools to model their problems.

Conclusion

A decrease in the technological barrier of simulation can be accomplished combining tools like Pandora with Cloud Computing.

Once a simulation is deployed, the image can be shared between researchers, and the models reused.

Cloud Computing provides to Humanities departments without access to supercomputers a reasonable solution to deal with computational costs.

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Thank you!

ABM can improve the way battlefields are excavatedCloud-based HPC can solve the computational challenge of these simulationsThe increase in CPU power will benefit the research on Humanities

xavier.rubio@bsc.es

If you are interested you can test Pandora at: http://github.com/xrubio/pandora