13,398 research outputs found
Interoperability and Information Brokers in Public Safety: An Approach toward Seamless Emergency Communications
When a disaster occurs, the rapid gathering and sharing of crucial information among public safety agencies, emergency response units, and the public can save lives and reduce the scope of the problem; yet, this is seldom achieved. The lack of interoperability hinders effective collaboration across organizational and jurisdictional boundaries. In this article, we propose a general architecture for emergency communications that incorporates (1) an information broker, (2) events and event-driven processes, and (3) interoperability. This general architecture addresses the question of how an information broker can overcome obstacles, breach boundaries for seamless communication, and empower the public to become active participants in emergency communications. Our research is based on qualitative case studies on emergency communications, workshops with public safety agencies, and a comparative analysis of interoperability issues in the European public sector. This article features a conceptual approach toward proposing a way in which public safety agencies can achieve optimal interoperability and thereby enable seamless communication and crowdsourcing in emergency prevention and response
Complexity, transparency and time pressure: practical insights into science communication in times of crisis
A global crisis such as the COVID-19 pandemic that started in early 2020 poses significant challenges for how research is conducted and communicated. We present four case studies from the perspective of an interdisciplinary research institution that switched to “corona-mode” during the first two months of the crisis, focussing all its capacities on COVID-19-related issues, communicating to the public directly and via media, as well as actively advising the national government. The case studies highlight the challenges posed by the increased time pressure, high demand for transparency, and communication of complexity and uncertainty. The article gives insights into how these challenges were addressed in our research institution and how science communication in general can be managed during a crisis
Decentralized data fusion and data harvesting framework for heterogeneous dynamic network systems
Diese Dissertation behandelt das Thema der dezentralisieren Sammlung und
Fusion von Daten in heterogenen, ressourcenbeschraekten und dynamischen
Netzwerkszenarien.
Dazu wird ein generisches Framework vorgestellt, dass
es erlaubt die Datensammlung, den Datenaustausch und auch die Datenfusion
dynamisch zu konfigurieren. Im Zuge dessen wird auch eine Methode zur
gerichteten Fusion von Daten auf graphentheoretischer Basis eingefrt, die
es erlaubt eine logische Struktur fuer die Fusion von Informationen zu
modellieren. Eine Markup-Sprache, die sowohl menschen- als auch
maschinenlesbar ist, erlaubt es diese Struktur leicht zu editieren.
Im
Bereich der Protokolle zum Datenaustausch liegt der Fokus dieser Arbeit auf
Energieeffizienz, um auch ressourcenbeschraenkte Geraete einzubinden. Ein
weiterer Schwerpunkt liegt auf Robustheit fuer die betrachteten dynamischen
Szenarien.
Diese Dissertation schlaet zudem Design-Richtlinien vor, um
verschiedene Ziele fuer unterschiedliche Applikationen umzusetzen. Diese
lassen sich leicht in das vorgestellte Framework integrieren und darueber
konfigurieren. Dadurch ergibt sich im Ganzen eine flexible Architektur, die
sich leicht an dynamische Umgebungen anpassen laesst.With the increasing number of available smart phones, sensor nodes, and
novel mobile smart devices such as Google glass, a large volume of data
reflecting the environment is generated in the form of sensing data sources
(such as GPS, received signal strength identification, accelerometer,
microphone, images, videos and gyroscope, etc.). Some context-aware and
data centric applications require the online processing of the data
collected. The thesis researches on the decentralized data fusion and data
harvesting framework for heterogeneous dynamic network system consisting of
various devices with resource constraints. In order to achieve the flexible
design, a general architecture is provided while the detailed data fusion
and data exchange functions can be dynamically configured. A novel method
to use directed fusion graph to model the logical structure of the
distributed information fusion architecture is introduced. This directed
fusion graph can accurately portray the interconnection among different
data fusion components and the data exchange protocols, as well as the
detailed data streams. The directed fusion graph is then transformed into a
format with marked language, so that both human and machine can easily
understand and edit. In the field of data exchange protocols, this thesis
targets energy-efficiency considering the resource constraints of the
devices and robustness, as the dynamic environment might cause failures to
the system. It proposes a refined gossip strategy to reduce retransmission
of redundant data. The thesis also suggests a design guideline to achieve
different design aims for different applications. These results in this
field can be integrated into the framework effortlessly. The configuration
mechanism is another feature of this framework. Different from other
research work which consider configuration as a post-design work separated
from the main design of any middle-ware. This thesis considers the
configuration part as another dimension of the framework. The whole
strategy in configuration sets up the foundation for the flexible
architecture, and makes it easy to adapt to the dynamic environment. The
contributions in the above fields lead to a light-weight data fusion and
data harvesting framework which can be deployed easily above wireless
based, heterogeneous, dynamic network systems, even in extreme conditions,
to handle data-centric applications
The Use of Social Media in Emergency Management by Public Agencies and Non-Governmental Organizations: Lessons Learned From Areas Affected by Hurricanes Isaac, Sandy, and Harvey
Natural disasters are increasingly costly for the United States. The literature suggests emergency managers may improve disaster outcomes and enhance disaster resilience by supplementing their official public-communications methods with more bi-directional communication tactics using social media. This study aims to understand how social media is used within the “whole community” of emergency management in areas affected by recent hurricanes. The first research objective examines how social media is used by governmental and non-governmental organizations across the four phases of emergency management (preparedness, response, recovery, mitigation). The second objective is to identify challenges governmental and non-governmental groups have encountered and strategies they recommend addressing these problems. The third objective is to examine how social media was used by disaster responders specifically during the response phase of Hurricane Harvey in 2017. We conducted a survey of 269 organizations in areas affected by Hurricanes Isaac and Sandy in 2012 to address research objectives one and two, and for the third objective, surveyed 64 organizations who contributed to the rescue and response efforts during Hurricane Harvey. The first survey found respondents representing government-related organizations use social media more during the response and the preparedness phases, while non-governmental groups report more social media activity during the recovery phase. This finding suggests that organizations performing primary and secondary roles in emergency management play complementary roles in risk and crisis communication with the public. The results also suggest that the emergency management community primarily uses social media to “push” information to the public through established communication networks and could benefit from additional efforts to “pull” information from their networks. Survey respondents report greatest concern about challenges external to their organizations, with the accuracy of information found on social media to be most concerning. The third research objective finds generally high levels of social media use among Hurricane Harvey responders, but also evidence of technical challenges including an inability to convert web-based communications to dispatchable missions due to limited functionality of their 911 systems. The results of the study provide insights regarding uses, challenges, and strategies to improve social media for the whole community of emergency management
Data Storage and Dissemination in Pervasive Edge Computing Environments
Nowadays, smart mobile devices generate huge amounts of data in all sorts of gatherings.
Much of that data has localized and ephemeral interest, but can be of great use if shared
among co-located devices. However, mobile devices often experience poor connectivity,
leading to availability issues if application storage and logic are fully delegated to a
remote cloud infrastructure. In turn, the edge computing paradigm pushes computations
and storage beyond the data center, closer to end-user devices where data is generated
and consumed. Hence, enabling the execution of certain components of edge-enabled
systems directly and cooperatively on edge devices.
This thesis focuses on the design and evaluation of resilient and efficient data storage
and dissemination solutions for pervasive edge computing environments, operating with
or without access to the network infrastructure. In line with this dichotomy, our goal can
be divided into two specific scenarios. The first one is related to the absence of network
infrastructure and the provision of a transient data storage and dissemination system
for networks of co-located mobile devices. The second one relates with the existence of
network infrastructure access and the corresponding edge computing capabilities.
First, the thesis presents time-aware reactive storage (TARS), a reactive data storage
and dissemination model with intrinsic time-awareness, that exploits synergies between
the storage substrate and the publish/subscribe paradigm, and allows queries within a
specific time scope. Next, it describes in more detail: i) Thyme, a data storage and dis-
semination system for wireless edge environments, implementing TARS; ii) Parsley, a
flexible and resilient group-based distributed hash table with preemptive peer relocation
and a dynamic data sharding mechanism; and iii) Thyme GardenBed, a framework
for data storage and dissemination across multi-region edge networks, that makes use of
both device-to-device and edge interactions.
The developed solutions present low overheads, while providing adequate response
times for interactive usage and low energy consumption, proving to be practical in a
variety of situations. They also display good load balancing and fault tolerance properties.Resumo
Hoje em dia, os dispositivos móveis inteligentes geram grandes quantidades de dados
em todos os tipos de aglomerações de pessoas. Muitos desses dados têm interesse loca-
lizado e efêmero, mas podem ser de grande utilidade se partilhados entre dispositivos
co-localizados. No entanto, os dispositivos móveis muitas vezes experienciam fraca co-
nectividade, levando a problemas de disponibilidade se o armazenamento e a lógica das
aplicações forem totalmente delegados numa infraestrutura remota na nuvem. Por sua
vez, o paradigma de computação na periferia da rede leva as computações e o armazena-
mento para além dos centros de dados, para mais perto dos dispositivos dos utilizadores
finais onde os dados são gerados e consumidos. Assim, permitindo a execução de certos
componentes de sistemas direta e cooperativamente em dispositivos na periferia da rede.
Esta tese foca-se no desenho e avaliação de soluções resilientes e eficientes para arma-
zenamento e disseminação de dados em ambientes pervasivos de computação na periferia
da rede, operando com ou sem acesso à infraestrutura de rede. Em linha com esta dico-
tomia, o nosso objetivo pode ser dividido em dois cenários específicos. O primeiro está
relacionado com a ausência de infraestrutura de rede e o fornecimento de um sistema
efêmero de armazenamento e disseminação de dados para redes de dispositivos móveis
co-localizados. O segundo diz respeito à existência de acesso à infraestrutura de rede e
aos recursos de computação na periferia da rede correspondentes.
Primeiramente, a tese apresenta armazenamento reativo ciente do tempo (ARCT), um
modelo reativo de armazenamento e disseminação de dados com percepção intrínseca
do tempo, que explora sinergias entre o substrato de armazenamento e o paradigma pu-
blicação/subscrição, e permite consultas num escopo de tempo específico. De seguida,
descreve em mais detalhe: i) Thyme, um sistema de armazenamento e disseminação de
dados para ambientes sem fios na periferia da rede, que implementa ARCT; ii) Pars-
ley, uma tabela de dispersão distribuída flexível e resiliente baseada em grupos, com
realocação preventiva de nós e um mecanismo de particionamento dinâmico de dados; e
iii) Thyme GardenBed, um sistema para armazenamento e disseminação de dados em
redes multi-regionais na periferia da rede, que faz uso de interações entre dispositivos e
com a periferia da rede.
As soluções desenvolvidas apresentam baixos custos, proporcionando tempos de res-
posta adequados para uso interativo e baixo consumo de energia, demonstrando serem
práticas nas mais diversas situações. Estas soluções também exibem boas propriedades de balanceamento de carga e tolerância a faltas
- …