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Natural disasters can severely disrupt conventional communication systems, hampering relief efforts. High-altitude tethered balloon base stations (HATBBSs) are a promising solution to communication disruptions, providing wide communication coverage in disaster-stricken areas. However, a single HATBBS is insufficient for large disaster zones, and limited resources may restrict the number and energy capacity of available base stations. To address these challenges, this study proposes a cluster deployment of tethered balloons to form flying ad hoc networks (FANETs) as a backbone for post-disaster communications. A meta-heuristic-based multi-objective particle swarm optimization (MOPSO) algorithm is employed to optimize the placement of balloons and power control to maximize target coverage and system energy efficiency. Comparative analysis with a stochastic algorithm (SA) demonstrates that MOPSO converges faster, with significant advantages in determining optimal balloon placement. The simulation results show that MOPSO effectively improves network throughput while reducing average delay and packet loss rate. [ABSTRACT FROM AUTHOR]

Background: Community resilience and health emergency communication are both crucial in promoting a community's ability to endure crises and recover from emergency events. Yet, a notable gap in theory and evidence exists in the relationship between them. We aim to explore the relationship between community resilience and health emergency communication and to identify strategies and interventions to strengthen their usefulness to each other. Based on the results, a secondary aim was to develop a model of community-centred resilience and health emergency communication. Methods: A systematic review of literature published between January 1990 and February 2024 was undertaken following Joanna Briggs Institute guidelines. Electronic databases (Web of Science, Social Science Citation Index, PubMed/MEDLINE) were searched using key terms. Eligibility criteria were developed from the literature and the knowledge of the multidisciplinary team. Inductive thematic analysis generated key themes. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were applied to present the findings. Results: The searches identified 300 articles, of which 86 met the inclusion criteria. Two main themes were identified from the literature: (i) the relationship between emergency communication and community resilience, including subthemes: building trust and collaboration within communities, identifying resources and their distribution, tailoring communication strategies, considering inclusion and equity, and community engagement and feedback and (ii) strategies and interventions, including subthemes: facilitating community structures as channels for communication, respecting personal and private boundaries in health communication, targeting outreach for effective crisis communication, building resilience through training and communication initiatives, and demonstrating commitment to equity and inclusion. Conclusions: There is a small, yet valuable, body of evidence to demonstrate the value of bolstering community-centred resilience for emergency preparedness, response and recovery. The model of community-centred resilience and health emergency communication developed can inform policy, research and practice. Further research is required to develop and test community-centred approaches to enhance inclusive risk communication and equitable recovery. [ABSTRACT FROM AUTHOR]

Emergency communication is a key link to ensure the stable operation of communication networks. And large-scale multiple-input multiple-output (MIMO) technology can significantly improve coverage of communication systems. This work aims to optimize the backhaul process through deep neural network to improve the response speed and data transmission efficiency of base stations. Specifically, the proposed method uses deep neural network to represent the backhaul process of base stations, and explores data transmission under high efficiency and low delay. Simulation experiments are designed to verify performance advantages of the proposed method in large-scale MIMO wireless ad hoc networking scenarios, by using three comparison metrics. The experimental results show that the proposed method has a significant performance improvement in data transmission rate, system stability and resource utilization compared with traditional methods. Besides, the feasibility and effectiveness of the algorithm in practical application are verified by simulation and actual environment test. To sum up, the proposed algorithm can provide a new direction for the technical research in the field of emergency communication. [ABSTRACT FROM AUTHOR]

The airborne relay system is an important support for improving the stability of communication systems in complex electromagnetic environments. As a key component of the airborne relay system, the antenna needs to have characteristics such as high gain, dual circular polarization, wide beam coverage, and miniaturization. Based on the septum circular polarizer, this paper proposes a high-performance circularly polarized antenna structure suitable for airborne relay systems, named AcpAS. The structure consists of a coaxial feed port, a coaxial-to-waveguide transition, a septum circular polarizer, and a parabolic metal housing. Based on this structure, two antennas operating at 19.6 GHz to 21.6 GHz and 29.2 GHz to 31.2 GHz are designed in this paper. Simulated and measured results show that the two antennas have dual circular polarization characteristics, with beam coverage range of more than ±55° for gains higher than 0 dBi, and the radiation patterns exhibit good symmetry and wide-beam coverage characteristics. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of coordinated resource allocation for multiple unmanned aerial vehicles (UAVs) to address the scarcity of communication resources in disaster-affected areas. UAVs carrying modules of free space optical (FSO) and radio frequency (RF) serve as relay nodes and edge offloading nodes, presenting an FSO/RF dual-hop framework. Considering the varying urgency levels of tasks, we assign task priorities and transform the proposed problem into distributed collaborative optimization problem. Based on the K-means algorithm and the multi-agent deep deterministic policy gradient (MADDPG) algorithm, we propose a UAV-coordinated K-means MADDPG (KMADDPG) to maximize the number of completed tasks while prioritizing high-priority tasks. Simulation results show that KMADDPG is 5% to 10% better than the benchmark DRL methods in convergence performance. [ABSTRACT FROM AUTHOR]

Aiming at the problems of complex and diversified communication networks in various emergency rescue scenarios and the independence of the command and communication systems of ordinary dispatch consoles, a SIP-based emergency communication console is proposed, which not only describes in detail the composition of the hardware modules of the console, but also elaborates on the application of SIP soft switching technology in the program. The console supports access to digital and analog communication networks to realize voice communication and multimedia video communication through wired and wireless broad band communication. Based on SIP soft switch technology, the concept of fully converged communication is proposed for the emergency communication needs under different emergency rescue scenarios to complete the unified command and dispatching, which provides a reference for the development direction of the emergency communication console.

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The low coverage of public networks in pristine forest areas prevents on-site firefighters from communicating directly with remote command centers during forest fires, reducing firefighting efficiency. In this study, we designed a vehicle-mounted emergency communication system Using BeiDou RSMC (Regional Short Message Communication) for firefighting operations in forest areas without a public network to establish a satellite communication network and Zigbee self-organizing network technology to establish a local self-organizing network. Beidou RSMC is a satellite communication service developed and operated independently by China, and its signals now cover the entire globe. The combination of these two components ensures emergency communication in the event of a fire in a forest area without public network coverage. The performance of the system was tested by simulating a fire, and it was able to establish a reliable communication link between the firefighters on the scene and the remote command center in the absence of a public network. The proposed system solves the emergency communication problem that arises when a fire occurs in a forest area without a public network, enabling the remote command center to monitor fire information and dispatch various resources in real time, thereby improving firefighting efficiency and reducing casualties. [ABSTRACT FROM AUTHOR]

Building a resilient society is key to preparing for disasters beyond the planned scale. To achieve this, it is necessary to create a clear common understanding of what "resilient" disaster management means and to consider concrete methods to accelerate its social implementation. However, few opportunities have occurred to have these discussions with diverse stakeholders. Therefore, a panel discussion was held to consider the type of cooperation required to build a resilient society. Each speaker provided information from various perspectives, including emergency information, disaster prevention education, and scientific knowledge on the mechanism of tsunamis, and their impact on ecosystems. Based on the above, the panel discussion confirmed the need for various elements such as infrastructure, information, rules, and social structure. In particular, it is necessary to develop consistency with existing safety standards for disaster prevention using ecosystems. It was suggested that, in addition to the practice of education, cooperation with the media, which keeps up-to-date information on a long-term basis, is indispensable for raising awareness of disaster prevention. This panel discussion emphasized that disaster reduction is a difficult field for companies to enter and commercialize, however, it was emphasized that it is indispensable worldwide. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the underground communication link of the mine is interrupted and the information of rescuers cannot be exchanged after the disaster, a mine intrinsically safe AD hoc network base station is designed. Based on the SDR platform, the equipment adopts the scheme of FPGA + ADI AD9361+ intrinsic safety circuit, and uses wireless multi-hop, self-organization and strong self-healing ability of wireless mesh network technology to quickly and conveniently form a wireless communication network in the environment of underground power supply and communication system being destroyed, and at the same time, provides wireless coverage for terminal equipment such as handheld terminals, mine control balls, mine information recorders, etc., to realize information exchange between the accident scene and the forward command. The test results show that the base station has the advantages of self-provided power supply, high safety factor, small size, light weight, small power consumption, etc., 2.4 GHz and 1.4 GHz dual-band wireless networking, multi-hop capability of 6-8 hops of video, single-hop transmission distance greater than 200 meters, single-hop transmission delay of less than 7 ms, power consumption of less than 15 W, and continuous work for 4.5 h, which can solve the communication problems encountered in the emergency rescue process of various accidents and disasters in mines.

A total of 29 recent agricultural-related injuries and fatalities throughout the state of Indiana were identified and analyzed for their proximity to cellular towers and emergency medical services (EMS). The objective of this research was to identify relationships between selected agricultural incidents and the ability of the victim to successfully contact emergency services. The geographic information system (GIS) software ArcGIS Pro and ArcGIS Online were utilized for trend identification and analysis. Findings from this analysis showed that only one EMS provider was most likely to be found within five miles of a given incident location. This frequency increased to seven EMS providers when the proximity range was increased to ten miles of a given incident location. The analysis also showed that only one cellular tower was most likely to be within a 10-mile radius of a given incident. There were frequently no accessible towers within five miles of a given incident. In addition, identified incidents were overlaid on a digital elevation map (DEM) of Indiana for analysis on the relationship between elevation and the number of accessible cell towers in the area. Studies have confirmed that victims of serious agricultural-related injuries, especially while working alone, face significant barriers in alerting EMS of their need for assistance. Geospatial analysis techniques performed in this study can be utilized by other states to assess access to EMS and for larger-scale, agricultural incident analysis. These tools have the potential to improve detail in agricultural incident reporting. [ABSTRACT FROM AUTHOR]

As the frequency of natural disasters increases, the study of emergency communication becomes increasingly important. The use of federated learning (FL) in this scenario can facilitate communication collaboration between devices while protecting privacy, greatly improving system performance. Considering the complex geographic environment, the flexible mobility and large communication radius of unmanned aerial vehicles (UAVs) make them ideal auxiliary devices for wireless communication. Using the UAV as a mobile base station can better provide stable communication signals. However, the number of ground-based IoT terminals is large and closely distributed, so if all of them transmit data to the UAV, the UAV will not be able to take on all of the computation and communication tasks because of its limited energy. In addition, there is competition for spectrum resources among many terrestrial devices, and all devices transmitting data will bring about an extreme shortage of resources, which will lead to the degradation of model performance. This will bring indelible damage to the rescue of the disaster area and greatly threaten the life safety of the vulnerable and injured. Therefore, we use user scheduling to select some terrestrial devices to participate in the FL process. In order to avoid the resource waste generated by the terrestrial device resource prediction, we use the multi-armed bandit (MAB) algorithm for equipment evaluation. Considering the fairness issue of selection, we try to replace the single criterion with multiple criteria, using model freshness and energy consumption weighting as reward functions. The state of the art of our approach is demonstrated by simulations on the datasets. [ABSTRACT FROM AUTHOR]

The integrated emergency communication network for railways faces big challenges in achieving rapid construction due to its involvement of many services and technologies. One research topic worthy of attention is how to achieve the rapid construction of integrated emergency communication networks, while meeting the different needs of various services and multiple scenarios and ensuring the stability and effectiveness of communication networks. This paper draws the inspiration from the new concept of separation between control layer and data layer in software defined network (SDN), and makes the proposal the SDN technology should be introduced to emergency communication. Thus, SDN-based integrated emergency communication networks can be established to achieve such related functions as centralized network control, state perception and on-demand routing, and improve network stability and efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Communication recovery is necessary for rescue and reconstruction scenarios including earthquakes, typhoons, floods, etc. The rapid and stable communication link can provide efficient victims' real-time information for the rescue process. However, traditional centralized communication links cannot traverse the further victims with information-sharing requirements. And the even communication link distribution leads to a load burden on the crowded victim area. Thus, we propose a three-layer architecture consisting of the emergency communication vehicle, backbone links, and branch links to rapidly recover communication via mobile robots. Then, considering victims' distribution, an improved MaxMin distance algorithm is presented as the basis of robot dispatch. The relay probability of the link is also estimated with closed formulae. Finally, simulation results verify that our proposed algorithm can recover communication with lower delay and higher packet delivery ratio. [ABSTRACT FROM AUTHOR]

Emergency communication networks play a vital role in disaster monitoring, transmission, and application during disaster emergency response (DER), however, the performance and stability of edge nodes in the emergency communication networks are often weak due to limited communication and computation resources. This weakness directly affects the quality of service (QoS) of the geospatial edge service (GES) chains involved in emergency monitoring. Existing research predominantly addresses service compositions in stable environments, neglecting the aggregation of efficient and robust GES chains in emergency communication networks. This study proposes an evolutionary particle swarm optimization (EPSO)-based emergency monitoring GES chain in an emergency communication network. It includes a GES chain model of emergency environment monitoring for tailing areas, as well as the designs of the particle chromosome encoding method, fitness evaluation model, and particle chromosome swarm update operators of the EPSO-based GES chain. Finally, the study conducts emergency environment monitoring experiments for tailing areas using the proposed method. Experiments results demonstrate that the proposed method significantly enhances the efficiency, stability, and reliability of emergency monitoring GES chains in the emergency communication network. This is crucial to providing fast and reliable services for DER during natural disasters.

The airborne relay system is an important support for improving the stability of communication systems in complex electromagnetic environments. As a key component of the airborne relay system, the antenna needs to have characteristics such as high gain, dual circular polarization, wide beam coverage, and miniaturization. Based on the septum circular polarizer, this paper proposes a high-performance circularly polarized antenna structure suitable for airborne relay systems, named AcpAS. The structure consists of a coaxial feed port, a coaxial-to-waveguide transition, a septum circular polarizer, and a parabolic metal housing. Based on this structure, two antennas operating at 19.6 GHz to 21.6 GHz and 29.2 GHz to 31.2 GHz are designed in this paper. Simulated and measured results show that the two antennas have dual circular polarization characteristics, with beam coverage range of more than ±55° for gains higher than 0 dBi, and the radiation patterns exhibit good symmetry and wide-beam coverage characteristics.

This paper investigates the problem of coordinated resource allocation for multiple unmanned aerial vehicles (UAVs) to address the scarcity of communication resources in disaster-affected areas. UAVs carrying modules of free space optical (FSO) and radio frequency (RF) serve as relay nodes and edge offloading nodes, presenting an FSO/RF dual-hop framework. Considering the varying urgency levels of tasks, we assign task priorities and transform the proposed problem into distributed collaborative optimization problem. Based on the K-means algorithm and the multi-agent deep deterministic policy gradient (MADDPG) algorithm, we propose a UAV-coordinated K-means MADDPG (KMADDPG) to maximize the number of completed tasks while prioritizing high-priority tasks. Simulation results show that KMADDPG is 5% to 10% better than the benchmark DRL methods in convergence performance.

Abstract Communication recovery is necessary for rescue and reconstruction scenarios including earthquakes, typhoons, floods, etc. The rapid and stable communication link can provide efficient victims’ real-time information for the rescue process. However, traditional centralized communication links cannot traverse the further victims with information-sharing requirements. And the even communication link distribution leads to a load burden on the crowded victim area. Thus, we propose a three-layer architecture consisting of the emergency communication vehicle, backbone links, and branch links to rapidly recover communication via mobile robots. Then, considering victims’ distribution, an improved MaxMin distance algorithm is presented as the basis of robot dispatch. The relay probability of the link is also estimated with closed formulae. Finally, simulation results verify that our proposed algorithm can recover communication with lower delay and higher packet delivery ratio.

Mine Internet of Things (MIoT) is of great significance in mine production monitoring and disaster prediction. However, the MIoT is easily affected by mine accidents in data transmission. Accidents often lead to the damage of IoT nodes (IoTN). The surviving IoTNs are limited by low quantity and energy, so it is difficult to complete the task of collecting and transmitting a large number of monitoring data in the roadway. In order to ensure the reliable and energy-efficient data communication of MIoT after disaster, an unmanned aerial vehicle (UAV)-assisted clustered MIoT communication system architecture is established. Based on this, an UAV-assisted data gathering method based on clustering and A* search is proposed. Firstly, the energy consumption of IoTNs and the path length of UAV are considered to construct the objective function. The optimal K is determined by plotting the relationship between the variance distance from the node to the cluster center and the path length of UAV data gathering and different K values. Then the K-means algorithm is used to divide all IoTNs into K clusters. Next, by considering the data gathering energy consumption of UAV and IoTNs, the path planning problem of UAV is established as an optimization problem to minimize the overall energy consumption of MIoT system, and an improved A* search algorithm for UAV data collection path planning is proposed. In this algorithm, the starting point of UAV and all clustering information are input into A * network by using the pointer network. A group of sorted cluster heads output by A * network is the flight path of UAV. Simulation results show that compared with the flat-based UAV data gathering method, the proposed data gathering method significantly reduces the energy consumption of UAV; Compared with two clustered-based UAV data acquisition methods, the proposed method effectively reduces the average and total energy consumption of IoTNs. Therefore, the proposed UAV-assisted data gathering method improves the energy consumption of the MIoT system after disaster, prolongs the network lifetime, and plays an important role in improving the reliability of the MIoT data gathering system after disaster.

Enhancing preparedness that enables people and communities to effectively anticipate, respond to, and recover from the impacts of a wildfire requires interactive communication. The purpose of this research is to understand how municipalities are communicating with communities regarding wildfires. Municipalities represent the lowest level of governance in Portugal and their responsibility for wildfire risk communication is fixed by law. In addition, this paper evaluates the influence of experience with extreme wildfires on communication processes. An online questionnaire was sent to 275 Portugal mainland municipalities (the official number of municipalities is 278, but three municipalities were not considered because they are entirely urban areas without wildland). One hundred and one municipalities participated in the survey (37% response rate). The survey identified the predominant use of one-way communication, lack of continuity of communication activities, and lack of purpose and content of the awareness-raising activities. The main difficulty municipalities encountered was the lack of interest from several target groups, which was mainly due to them continuing to use ineffective communication and not engaging citizens in the process. Considering the contact between municipalities and their citizens, a more interactive role in the wildfire communication process by using two-way communication exchanges is advocated to enhance preparedness and avoid casualties and losses. [ABSTRACT FROM AUTHOR]

Reliable sensing of roadway conditions during flooding is a long-standing, challenging problem with societal importance for roadway safety. Tools that provide real-time data on road conditions during floods can facilitate safer mobility, reduce vehicle-related drownings, enhance flood response efficiency, and support emergency response decision-making. Following the tenets of user-centered design, such tools ideally should address the needs of diverse stakeholders involved in flood response. Currently, the existing literature lacks a thorough understanding of stakeholder needs to guide situational awareness tool development in the area of roadway mobility during flood events. This paper addresses this gap by studying the needs of stakeholders responsible for managing flood response in Houston. Semi structured one-on-one interviews were conducted with stakeholders from different Houston-based organizations responsible for managing and responding to flood hazard events in the downtown metropolitan area. Interview responses were systematically analyzed to identify (1) data needs for facilitating efficient and safe emergency response, (2) the most and least valuable information available during flooding, (3) communication and visualization strategies, (4) factors influencing stakeholder trust, and (5) factors influencing occupational stress during flood response. Finally, interview insights were used to develop a conceptual situational awareness framework and a prototype map-based tool that provides real-time road condition data during flood events. This study elucidates vital information for improving existing tools and providing preliminary guidance for future mobility-centric situational awareness tools that promote safer mobility and facilitate emergency response decision-making during flooding. Although the study focused on Houston, insights gained may be useful for comparable flood-prone regions. In developed countries, 40%–60% of flood fatalities are attributed to vehicle-related incidents. Flooded roads and lack of real-time road condition data pose safety risks to first responders and reduce emergency response efficiency. Understanding stakeholder needs and developing tools that address them are essential for improving the safety and efficiency of emergency response, especially considering a potential increase in flood risk to urban mobility due to climate change and other factors. Following the tenets of the user-centered design process, this study identified stakeholder needs, conceptualized a framework for sensing road conditions, and developed an open-source prototype tool in the context of flood response in Houston. Insights gained in this study can improve the efficacy of existing mobility-centric situational awareness tools and provide preliminary guidance for quick prototyping of new situational awareness tools. Furthermore, organizations can use the insights presented here to help reduce work-related stress among emergency response personnel, thereby improving emergency response efficiency and organizational resilience. [ABSTRACT FROM AUTHOR]

To carry out the system design and technology development for emergency communications, and greatly improve our ability of risk prevention and emergency disposal, the research on multi-unmanned aerial vehicle (multi-UAV) cooperative channel model for emergency communications was carried out.First, the channel dataset of multi-UAV cooperative emergency communications in two typical emergency environments, i.e., the urban earthquake and suburban blizzard, was established.The channel parameters and statistical properties of multi-UAV cooperative emergency communications were analyzed.Second, a more general geometry-based stochastic channel model (GBSM) was proposed for multi-UAV cooperative emergency communications.The channel impulse response (CIR) and the cooperative non-station arity of multi-UAV cooperative channels in the space and time domains in multi-UAV cooperative emergency communications were calculated and captured.Finally, the channel characteristics of multi-UAV cooperative emergency communication in urban earthquake and suburban blizzard scenarios were analyzed, which could support the practical implementation of multi-UAV cooperative emergency communications.Meanwhile, the statistical characteristic of the proposed model can fit well with that of ray-tracing-based channel data, verifying the utility of the proposed model.

To address the information collection and aggregation issue in emergency scenarios characterized by the lack of public infrastructure and unstable satellite signals, an information timeliness-oriented information collection and transmission scheduling mechanism was proposed for emergency unmanned aerial vehicle (UAV) networks where information collection and transmission capabilities were constrained by energy consumption.Considering the age of information (AoI) as the metric and constraint of information timeliness, a stochastics optimization problem was constructed with the objective of minimizing UAV information collection and transmission energy consumption.By resorting to the Lyapunov optimization technique, virtual queues were established to impose information timeliness constraints on queue lengths, and the original problem was decoupled into two sub-problems, information collection and transmission scheduling, with the premise of ensuring system stability.Corresponding heuristic algorithms were proposed for each sub-problem.Simulation results demonstrate that the proposed algorithm outperforms conventional queue scheduling approaches in convergence rates and system energy consumption with guaranteed information timeliness.

In order to fully grasp the current situation and development trend of mine emergency rescue research in China, based on China National Knowledge Infrastructure database, VOSviewer and CiteSpace were used to conduct bibliometric visualization analysis from multiple perspectives such as the number of publications, research institutions, researchers, journal sources and keywords, and the evolution process of emergency rescue research hotspots was analyzed from three aspects: management, technology and equipment. The results show that the research on mine emergency rescue in China has mainly experienced three stages of development: initial germination, rapid development and high fluctuation, and the number of published papers is on the rise. Research institutions are dominated by universities. The research team is distinctive, but the cooperation needs to be strengthened. At present, the research hotspots focus on emergency plan, emergency command, emergency communication, emergency drill, rescue equipment and IoT monitoring. Information technology plays an increasingly important role in mine disaster perception, transmission, evaluation, decision-making and command. Intelligence, informatization and integration have become the main development trend of mine emergency rescue in the future.

This article studies mobile edge computing technologies enabled by unmanned aerial vehicles (UAVs) in disasters. First, considering that the ground servers may be damaged in emergency scenarios, we proposed an air-ground cooperation architecture based on ad-hoc UAV networks. We defined the system cost as the weighted sum of task delay and energy consumption because of different delay sensitivity and energy sensitivity tasks in emergency communication networks. Then, we formulated the system cost-minimization problem of task scheduling and multi-UAV deployments. To solve the proposed mixed integer nonlinear programming problem, we decomposed it to two sub-problems that were solved by proposing a swap matching-based task scheduling sub-algorithm and a successive convex approximation-based multi-UAV deployment sub-algorithm. Accordingly, we propose a joint optimization algorithm by iterating the two sub-algorithms to obtain a low complexity sub-optimal solution. Finally, the simulation results show that (i) the proposed algorithm converges in several iterations, and (ii) compared with the benchmark algorithms, the proposed algorithm has better performance of reducing task delay and energy consumption and achieves a good trade-off between them for diverse tasks. [ABSTRACT FROM AUTHOR]

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Copyright of Historia y Comunicación Social is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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To solve the problem of small coverage area and discontinuous coverage of large fixed-wing aerospace emergency base stations, a design scheme for continuous coverage of UAV emergency base stations was proposed.Based on the analysis of the coverage capability of the single antenna of the airborne base station, a multi-antenna coverage scheme with inner antenna plus edge antenna was proposed.Taking the roll angle, pitch angle and other parameters of the UAV flight into consideration, the installation plan of multi-antenna mounting that guarantees continuous coverage was designed.Then the link budget was carried out according to the 3GPP propagation loss model, and the UAV flight plan was planned according to the continuous coverage area requirements.Simulation and flight test results show that the proposed scheme can achieve 50 km2 continuous signal coverage of the ground by the mobile base station on the UAV without using the intelligent control of the antenna angle of the PTZ.

In order to quickly restore emergency communication services for large-scale post-disaster users, a distributed intellicise coverage optimization architecture based on multi-agent reinforcement learning (RL) was proposed, which could address the significant differences and dynamics of communication services caused by a large number of access users, and the difficulty of expansion caused by centralized algorithms.Specifically, a distributed k-sums clustering algorithm considering service differences of users was designed in the network characterization layer, which could make each unmanned aerial vehicle base station (UAV-BS) adjust the local networking natively and simply, and obtain states of cluster center for multi-agent RL.In the trajectory control layer, multi-agent soft actor critic (MASAC) with distributed-training-distributed-execution structure was designed for UAV-BS to control trajectory as intelligent nodes.Furthermore, ensemble learning and curriculum learning were integrated to improve the stability and convergence speed of training process.The simulation results show that the proposed distributed k-sums algorithm is superior to the k-means in terms of average load efficiency and clustering balance, and MASAC based trajectory control algorithm can effectively reduce communication interruptions and improve the spectrum efficiency, which outperforms the existing RL algorithms.

In public emergencies such as accident relief, rescue workers are faced with challenges, such as poor communication, unstable navigating, and inaccurate disaster sensing.It is necessary to deploy an emergency unmanned aerial vehicle (UAV) network to guarantee the services of communication-navigating-sensing.Aiming at alleviating the problem of limited energy of UAV, a low-energy-consumption deployment of an emergency UAV network was first proposed for integrated communication-navigating-sensing (ICNS).The proposed scheme was able to realize network topology reconstruction and role cognition on demand.Then, a particle swarm algorithm based hierarchical matching decision-making algorithm was presented to jointly optimize three sub-problems, including the associations between UAVs and users, the resource allocation for multi-role UAV communications, and the UAV position.Simulation results show that the proposed ICNS scheme can achieve flexible adaptation of the multi-objective requirements and limited network resources, and dramatically reduce the demand for the number of UAVs and the deployment energy consumption.

In the study of "Effective Emergency Communication through Public Displays," our research indicates major advancements and problems in using public displays to disseminate essential information during crises. According to data research, there has been a 33% rise in the deployment of high-resolution 4K TVs, showing a technical change toward improved message visibility and clarity. Geographic distribution has improved, with a 10% increase in ideal placements in high-risk regions due to population density and vulnerability evaluations. Message design and content adherence to plain language standards, as well as the usage of visual aids and standardized symbols, have all increased by 5%. The psychological components of message reception highlight the necessity of simple language and high-resolution panels, as LED screens result in a 15% higher message understanding rate than LCD screens, while jargon-laden messages raise audience anxiety levels by 25%. Although resilience evaluations have shown a 15% increase in the existence of backup power supplies and a 10% rise in remote monitoring capabilities, 20% of installations still have physical vulnerabilities. These results suggest a complete strategy to improving the efficacy of public displays for emergency communication, highlighting the need of continual technological improvements and best practices to protect the safety and well-being of different groups during disasters.

Using the innovative Emergency Alert and Social Media Engagement Test (EASE Test), this study examines how the dynamics of emergency communication are changing and how conventional emergency alerts and social media engagement may work together. The results of the data analysis show that participants' alarm reaction efficacy varied, depending on things like alert clarity and personal readiness. The research highlights the potential of social media platforms as dynamic centers for information exchange by revealing varying degrees of involvement under simulated emergency circumstances. Furthermore, it is shown that social media participation is positively correlated with alert reactions that are more successful, highlighting the function of social media in improving response preparedness. Qualitative information obtained from participant interviews clarifies the potential and challenges in this interaction. In light of the potential for improved public safety, situational awareness, and catastrophe resilience in the digital age, this study supports an integrated strategy.

The 5G device to device (D2D) communication is being given impetus as technology for achieving sustainable development goals (SDG) in various fields like health, smart city, education, infrastructure and clean energy. The low latency device to device communications are key enablers for achieving the goals and objectives promulgated as SDG. Network virtualisation, software defined networks, beamforming, artificial intelligence and cognitive methods are facilitating roll out of applications enabling achievement of SDG. The interference mitigation, efficient resource allocation, energy efficiency, mobility management, Quality of Service, scalability, standardisation and interoperability are few challenges being addressed to facilitate implementation of technology and its applications. In this paper existing work on D2D communications, its applications and research challenges has been reviewed. The impetus to D2D and mission critical communications by 3GPP frameworks and releases has been summarized. The SDG applications and research challenges have been analysed to highlight its implications on roll out of technology to achieve the SDG objectives and goals. These SDG applications and technology have the prospective to transform varied fields of health, education, infrastructure and industry for achieving goals.

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Unmanned Aerial Vehicles (UAVs) can be deployed as aerial wireless base stations which dynamically cover the wireless communication networks for Ground Users (GUs). The most challenging problem is how to control multi-UAVs to achieve on-demand coverage of wireless communication networks while maintaining connectivity among them. In this paper, the cooperative trajectory optimization of UAVs is studied to maximize the communication efficiency in the dynamic deployment of UAVs for emergency communication scenarios. We transform the problem into a Markov game problem and propose a distributed trajectory optimization algorithm, Double-Stream Attention multi-agent Actor-Critic (DSAAC), based on Multi-Agent Deep Reinforcement Learning (MADRL). The throughput, safety distance, and power consumption of UAVs are comprehensively taken into account for designing a practical reward function. For complex emergency communication scenarios, we design a double data stream network structure that provides a capacity for the Actor network to process state changes. Thus, UAVs can sense the movement trends of the GUs as well as other UAVs. To establish effective cooperation strategies for UAVs, we develop a hierarchical multi-head attention encoder in the Critic network. This encoder can reduce the redundant information through the attention mechanism, which resolves the problem of the curse of dimensionality as the number of both UAVs and GUs increases. We construct a simulation environment for emergency networks with multi-UAVs and compare the effects of the different numbers of GUs and UAVs on algorithms. The DSAAC algorithm improves communication efficiency by 56.7%, throughput by 71.2%, energy saving by 19.8%, and reduces the number of crashes by 57.7%. [ABSTRACT FROM AUTHOR]

Copyright of IC: Revista Científica de Información y Comunicación is the property of Universidad de Sevilla, Departamento de Periodismo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)