14 research outputs found
Routing Diverse Evacuees with Cognitive Packets
This paper explores the idea of smart building evacuation when evacuees can
belong to different categories with respect to their ability to move and their
health conditions. This leads to new algorithms that use the Cognitive Packet
Network concept to tailor different quality of service needs to different
evacuees. These ideas are implemented in a simulated environment and evaluated
with regard to their effectiveness.Comment: 7 pages, 7 figure
Cloud Enabled Emergency Navigation Using Faster-than-real-time Simulation
State-of-the-art emergency navigation approaches are designed to evacuate
civilians during a disaster based on real-time decisions using a pre-defined
algorithm and live sensory data. Hence, casualties caused by the poor decisions
and guidance are only apparent at the end of the evacuation process and cannot
then be remedied. Previous research shows that the performance of routing
algorithms for evacuation purposes are sensitive to the initial distribution of
evacuees, the occupancy levels, the type of disaster and its as well its
locations. Thus an algorithm that performs well in one scenario may achieve bad
results in another scenario. This problem is especially serious in
heuristic-based routing algorithms for evacuees where results are affected by
the choice of certain parameters. Therefore, this paper proposes a
simulation-based evacuee routing algorithm that optimises evacuation by making
use of the high computational power of cloud servers. Rather than guiding
evacuees with a predetermined routing algorithm, a robust Cognitive Packet
Network based algorithm is first evaluated via a cloud-based simulator in a
faster-than-real-time manner, and any "simulated casualties" are then re-routed
using a variant of Dijkstra's algorithm to obtain new safe paths for them to
exits. This approach can be iterated as long as corrective action is still
possible.Comment: Submitted to PerNEM'15 for revie
Routing Diverse Crowds in Emergency with Dynamic Grouping
Evacuee routing algorithms in emergency typically adopt one single criterion
to compute desired paths and ignore the specific requirements of users caused
by different physical strength, mobility and level of resistance to hazard. In
this paper, we present a quality of service (QoS) driven multi-path routing
algorithm to provide diverse paths for different categories of evacuees. This
algorithm borrows the concept of Cognitive Packet Network (CPN), which is a
flexible protocol that can rapidly solve optimal solution for any user-defined
goal function. Spatial information regarding the location and spread of hazards
is taken into consideration to avoid that evacuees be directed towards
hazardous zones. Furthermore, since previous emergency navigation algorithms
are normally insensitive to sudden changes in the hazard environment such as
abrupt congestion or injury of civilians, evacuees are dynamically assigned to
several groups to adapt their course of action with regard to their on-going
physical condition and environments. Simulation results indicate that the
proposed algorithm which is sensitive to the needs of evacuees produces better
results than the use of a single metric. Simulations also show that the use of
dynamic grouping to adjust the evacuees' category and routing algorithms with
regard for their on-going health conditions and mobility, can achieve higher
survival rates.Comment: Contains 6 pages, 5 pages. Accepted by PerNEM' 201
Joint Optimization for Pedestrian, Information and Energy Flows in Emergency Response Systems With Energy Harvesting and Energy Sharing
The rapid progress in informatisation and electrification in transportation has gradually transferred public transport junctions such as metro stations into the nexus of pedestrian flows, information flows, computation flows and energy flows. These smart environments that are efficient in handling large volume passenger flows in routine circumstances can become even more vulnerable during emergency situations and amplify the losses in lives and property owing to power outage triggered service degradation and destructive crowed behaviours. On the bright side, the increasingly abundant resources contained in smart environments have enlarged the optimisation space of an evacuation process, yet little research has concentrated on the joint optimal resource allocation between transportation infrastructures and pedestrians. Hence, in the paper, we propose a queueing network based resource allocation model to comprehensively optimise various types of resources during emergency evacuations. Experiments are conducted in a simulated metro station environment with realistic settings. The simulation results show that the proposed model can considerably improve the evacuation efficiency as well as the robustness of the emergency response system during emergency situations
Emergency navigation, energy optimisation and cooperative algorithms for motion and evacuation
The increasing concentration of human populations in modern urbanised societies has aggravated the frequency and destruction of both natural and manmade disasters, and has motivated considerable research over the last few decades. Accompanying the development of computing technology, emergency navigation algorithms in built environment have evolved from off-line algorithms that direct evacuees in accordance with pre-deployed static evacuation plans to on-line algorithms that dynamically calculate egress paths for evacuees. However, these algorithms normally consider evacuees in a homogeneous manner, and ignore the different requirements and relative risk of death among different groups of people caused by different mobilities, physical strength, health conditions and level of resistance to hazard. Therefore, this work aims to develop systems and algorithms to dynamically customise distinct paths for different categories of evacuees. To this end, we borrow the concept of Cognitive Packet Network (CPN) and adapt it to the context of emergency navigation. On top of the CPN framework, we design several routing metrics to calculate distinct egress paths for different categories of evacuees. To improve the inter and intra-group coordination, several cooperative strategies are proposed to further optimise the routes calculated by the proposed routing algorithm.
To provide a more accurate prediction to the congestion level of each egress path during an evacuation process under the effect of panic behaviours, we combine the CPN based routing algorithm with a G-network model to analyse the congestion level on a path via capturing the dynamics of diverse categories of evacuees under the influence of panic and re-routing decisions from the navigation system. Finally, we extend our work to large scale evacuations, and propose a G-network based emergency navigation algorithm to direct vehicles to safe areas in the aftermath of a large-scale disaster in an energy and time efficient manner.Open Acces
Routing Diverse Evacuees with the Cognitive Packet Network Algorithm
Regarding mobility, health conditions and personal preferences, evacuees can be categorized into different classes in realistic environments. Previous emergency navigation algorithms that direct evacuees with a single decision rule cannot fulfil civilians’ distinct service requirements and increase the likelihood of inducing destructive crowd behaviours, such as clogging, pushing and trampling, due to diverse mobility. This paper explores a distributed emergency navigation algorithm that employs the cognitive packet network concept to tailor different quality of service needs to different categories of evacuees. In addition, a congestion-aware algorithm is presented to predict the future congestion degree of a path with respect to the observed population density, arrival rate and service rate of each route segment. Experiments are implemented in a simulated environment populated with autonomous agents. Results show that our algorithm can increase the number of survivors while providing improved quality of service
Emergency Navigation without an Infrastructure
Emergency navigation systems for buildings and other built environments, such as sport arenas or shopping centres, typically rely on simple sensor networks to detect emergencies and, then, provide automatic signs to direct the evacuees. The major drawbacks of such static wireless sensor network (WSN)-based emergency navigation systems are the very limited computing capacity, which makes adaptivity very difficult, and the restricted battery power, due to the low cost of sensor nodes for unattended operation. If static wireless sensor networks and cloud-computing can be integrated, then intensive computations that are needed to determine optimal evacuation routes in the presence of time-varying hazards can be offloaded to the cloud, but the disadvantages of limited battery life-time at the client side, as well as the high likelihood of system malfunction during an emergency still remain. By making use of the powerful sensing ability of smart phones, which are increasingly ubiquitous, this paper presents a cloud-enabled indoor emergency navigation framework to direct evacuees in a coordinated fashion and to improve the reliability and resilience for both communication and localization. By combining social potential fields (SPF) and a cognitive packet network (CPN)-based algorithm, evacuees are guided to exits in dynamic loose clusters. Rather than relying on a conventional telecommunications infrastructure, we suggest an ad hoc cognitive packet network (AHCPN)-based protocol to adaptively search optimal communication routes between portable devices and the network egress nodes that provide access to cloud servers, in a manner that spares the remaining battery power of smart phones and minimizes the time latency. Experimental results through detailed simulations indicate that smart human motion and smart network management can increase the survival rate of evacuees and reduce the number of drained smart phones in an evacuation process