13,506 research outputs found
Fast simulation of crowd collision avoidance
Real-time large-scale crowd simulations with realistic behavior, are important for many application areas. On CPUs, the ORCA pedestrian steering model is often used for agent-based pedestrian simulations. This paper introduces a technique for running the ORCA pedestrian steering model on the GPU. Performance improvements of up to 30 times greater than a multi-core CPU model are demonstrated. This improvement is achieved through a specialized linear program solver on the GPU and spatial partitioning of information sharing. This allows over 100,000 people to be simulated in real time (60 frames per second)
A survey of real-time crowd rendering
In this survey we review, classify and compare existing approaches for real-time crowd rendering. We first overview character animation techniques, as they are highly tied to crowd rendering performance, and then we analyze the state of the art in crowd rendering. We discuss different representations for level-of-detail (LoD) rendering of animated characters, including polygon-based, point-based, and image-based techniques, and review different criteria for runtime LoD selection. Besides LoD approaches, we review classic acceleration schemes, such as frustum culling and occlusion culling, and describe how they can be adapted to handle crowds of animated characters. We also discuss specific acceleration techniques for crowd rendering, such as primitive pseudo-instancing, palette skinning, and dynamic key-pose caching, which benefit from current graphics hardware. We also address other factors affecting performance and realism of crowds such as lighting, shadowing, clothing and variability. Finally we provide an exhaustive comparison of the most relevant approaches in the field.Peer ReviewedPostprint (author's final draft
Statistical analysis of chemical computational systems with MULTIVESTA and ALCHEMIST
The chemical-oriented approach is an emerging paradigm for programming the behaviour of densely distributed and context-aware devices (e.g. in ecosystems of displays tailored to crowd steering, or to obtain profile-based coordinated visualization). Typically, the evolution of such systems cannot be easily predicted, thus making of paramount importance the availability of techniques and tools supporting prior-to-deployment analysis. Exact analysis techniques do not scale well when the complexity of systems grows: as a consequence, approximated techniques based on simulation assumed a relevant role. This work presents a new simulation-based distributed tool addressing the statistical analysis of such a kind of systems, which has been obtained by chaining two existing tools: MultiVeStA and Alchemist. The former is a recently proposed lightweight tool which allows to enrich existing discrete event simulators with distributed statistical analysis capabilities, while the latter is an efficient simulator for chemical-oriented computational systems. The tool is validated against a crowd steering scenario, and insights on the performance are provided by discussing how these scale distributing the analysis tasks on a multi-core architecture
Group emotion modelling and the use of middleware for virtual crowds in video-games
In this paper we discuss the use of crowd
simulation in video-games to augment their realism. Using
previous works on emotion modelling and virtual crowds we
define a game world in an urban context. To achieve that, we
explore a biologically inspired human emotion model,
investigate the formation of groups in crowds, and examine
the use of physics middleware for crowds. Furthermore, we
assess the realism and computational performance of the
proposed approach. Our system runs at interactive frame-rate
and can generate large crowds which demonstrate complex
behaviour
An information theory based behavioral model for agent-based crowd simulations
Crowds must be simulated believable in terms of their appearance and behavior to improve a virtual environment’s realism. Due to the complex nature of human behavior, realistic behavior of agents in crowd simulations is still a challenging problem. In this paper, we propose a novel behavioral model which builds analytical maps to control agents’ behavior adaptively with agent-crowd interaction formulations. We introduce information theoretical concepts to construct analytical maps automatically. Our model can be integrated into crowd simulators and enhance their behavioral complexity. We made comparative analyses
of the presented behavior model with measured crowd data and two agent-based crowd simulators
Challenges to MDG achievement in low income countries : lessons from Ghana and Honduras
This paper summarizes the policy lessons from applications of the Maquette for MDG Simulations (MAMS) model to two low income countries: Ghana and Honduras. Results show that costs of MDGs achievement could reach 10-13 percent of GDP by 2015, although, given the observed low productivity in the provision of social services, significant savings may be realized by improving efficiency. Sources of financing also matter: foreign aid inflows can reduce international competitiveness through real exchange appreciation, while domestic financing can crowd out the private sector and slow poverty reduction. Spending a large share of a fixed budget on growth-enhancing infrastructure may mean sacrificing some human development, even if higher growth is usually associated with lower costs of social services. The pursuit of MDGs increases demand for skills: while this encourages higher educational attainments, in the short term this could lead to increased income inequality and a lower poverty elasticity of growth.Population Policies,,Achieving Shared Growth,Public Sector Economics&Finance,Public Sector Expenditure Analysis&Management
Pedestrian Flow Simulation Validation and Verification Techniques
For the verification and validation of microscopic simulation models of
pedestrian flow, we have performed experiments for different kind of facilities
and sites where most conflicts and congestion happens e.g. corridors, narrow
passages, and crosswalks. The validity of the model should compare the
experimental conditions and simulation results with video recording carried out
in the same condition like in real life e.g. pedestrian flux and density
distributions. The strategy in this technique is to achieve a certain amount of
accuracy required in the simulation model. This method is good at detecting the
critical points in the pedestrians walking areas. For the calibration of
suitable models we use the results obtained from analyzing the video recordings
in Hajj 2009 and these results can be used to check the design sections of
pedestrian facilities and exits. As practical examples, we present the
simulation of pilgrim streams on the Jamarat bridge.
The objectives of this study are twofold: first, to show through verification
and validation that simulation tools can be used to reproduce realistic
scenarios, and second, gather data for accurate predictions for designers and
decision makers.Comment: 19 pages, 10 figure
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