5,048 research outputs found
Enabling Disaster Resilient 4G Mobile Communication Networks
The 4G Long Term Evolution (LTE) is the cellular technology expected to
outperform the previous generations and to some extent revolutionize the
experience of the users by taking advantage of the most advanced radio access
techniques (i.e. OFDMA, SC-FDMA, MIMO). However, the strong dependencies
between user equipments (UEs), base stations (eNBs) and the Evolved Packet Core
(EPC) limit the flexibility, manageability and resiliency in such networks. In
case the communication links between UEs-eNB or eNB-EPC are disrupted, UEs are
in fact unable to communicate. In this article, we reshape the 4G mobile
network to move towards more virtual and distributed architectures for
improving disaster resilience, drastically reducing the dependency between UEs,
eNBs and EPC. The contribution of this work is twofold. We firstly present the
Flexible Management Entity (FME), a distributed entity which leverages on
virtualized EPC functionalities in 4G cellular systems. Second, we introduce a
simple and novel device-todevice (D2D) communication scheme allowing the UEs in
physical proximity to communicate directly without resorting to the
coordination with an eNB.Comment: Submitted to IEEE Communications Magazin
Energy Efficient UAV-Assisted Emergency Communication with Reliable Connectivity and Collision Avoidance
Emergency communication is vital for search and rescue operations following
natural disasters. Unmanned Aerial Vehicles (UAVs) can significantly assist
emergency communication by agile positioning, maintaining connectivity during
rapid motion, and relaying critical disaster-related information to Ground
Control Stations (GCS). Designing effective routing protocols for relaying
crucial data in UAV networks is challenging due to dynamic topology, rapid
mobility, and limited UAV resources. This paper presents a novel
energy-constrained routing mechanism that ensures connectivity, inter-UAV
collision avoidance, and network restoration post-UAV fragmentation while
adapting without a predefined UAV path. The proposed method employs improved Q
learning to optimize the next-hop node selection. Considering these factors,
the paper proposes a novel, Improved Q-learning-based Multi-hop Routing (IQMR)
protocol. Simulation results validate IQMRs adaptability to changing system
conditions and superiority over QMR, QTAR, and QFANET in energy efficiency and
data throughput. IQMR achieves energy consumption efficiency improvements of
32.27%, 36.35%, and 36.35% over QMR, Q-FANET, and QTAR, along with
significantly higher data throughput enhancements of 53.3%, 80.35%, and 93.36%
over Q-FANET, QMR, and QTAR.Comment: 13 page
INTERFACE MODE ASSIGNMENT METHOD FOR SELF-RECONSTRUCTION OF WIRELESS MESH NETWORKS
The key features of computer networks available for disaster situation is reliable, fault tolerance and self-configurable. Therefore, using wireless mesh network for disaster prevention and recover system has gain much attention from the research community in last decades. In addition, from the practical aspects of the network infrastructures of the disaster system, we should assume the core capabilities such as wireless connectivity in wide range, ease of use, and low cost so on. In this paper, we propose an interface mode assignment method for reconstructing a route from an isolated router to a gateway (GW) router in a wireless mesh network based on IEEE 802.11 infrastructure mode after a disaster occurrance. The proposed method assigns an adequate mode to each interface in an isolated router to recover the network reachability in distributed manner. Simulation results show the effectiveness of the proposed method via two different scenarios
Characterizing Logistics Operations Within a Federal Staging Area for Hurricane Response: A Qualitative Analysis of Federal, State and Local Perspectives
A successful deployment of logistics operations following a disaster is a collective contribution of federal, state, and local entities to ascertain an efficient and effective response. This research analyzes data from interviews with disaster response logistics experts from these entities. The objective is to investigate the information sources and planning processes used in these organizations to plan vehicle routes for critical resource deliveries to impacted areas. Special attention is directed to the impacts of incomplete knowledge of infrastructure status, such as road disruptions due to debris or flooding. Supported by both qualitative and quantitative evidence, the study finds that incomplete knowledge of infrastructure status poses serious critical transportation risks such as delivery delays in disaster relief distribution. This research reveals both similarities and differences in logistical decision-making among these organization types and emphasizes the need for improved information sharing and coordination among emergency response organizations. The findings of this research are expected to guide future initiatives aimed at disaster relief routing thereby enhancing emergency response capabilities and outcomes
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