260 research outputs found
Communicating with communities (CwC) during post-disaster reconstruction: an initial analysis
International organisations have acknowledged that providing information to and communicating with communities affected by disasters should be considered as an integral part of the humanitarian aid. Yet little is known on the information and communication needs of the population during the disaster reconstruction phase. This paper presents a case study of the information and communication needs of the population and the role of social media during the reconstruction process after the earthquake that struck Emilia-Romagna (Northern Italy) in 2012. Data were collected through field notes and a multiple choices questionnaire distributed online and by hand to community-based groups. Results show that the most sought information concerns housing and infrastructure reconstruction, funds/refunds, business recovery and damage assessment and that city councils and regional council are considered as the main source of the information. Communication channels used to search for reconstruction-related information vary between online and offline respondents. Social media technology is used by citizens affected as a platform to read and share recovery information and post queries rather than as an engagement tool with recovery agencies. Main barriers to engagement are lack of trust towards the authorities and the belief that authorities do not use social media to communicate with citizens. In this context, community-based groups, especially those supported by social media, play an important role in sharing recovery-related information to other residents, clarifying legal acts and regulations and providing informational support to the affected population
How do population movements fit within the framework of systemic risk?
Population movements are key elements shaping today's complex and interconnected societies. Movement of people underpins the circulation of capital, knowledge, ideas, culture, values and resources with systemic benefits but it also produces diverse risk implications. The varied and complex implications of human mobility (and immobility) are still poorly understood by existing systemic risk approaches. This literature review approaches human mobility from a more comprehensive and complex standpoint to understand how it fits within a wider framework of systemic risk. In this article, we explore the complementary ways in which movements matter for systemic risk considerations, namely as: 1) a dynamic force that shapes exposure, vulnerability and resilience to disasters across places and scales; 2) a feature and consequence of disasters that has the potential to amplify, extend and prolong the impacts of hazards, and 3) a lifeline for people and societies worldwide, whose disruption has significant implications on systemic risk globally. These considerations have important theoretical consequences for the integration of population movements in systemic risk frameworks, and they propose practical lessons learned for the disaster risk reduction arena. We conclude that human mobility should not be understood as a negative impact that must be prevented and mitigated but as a positive phenomenon which enablement and protection a will lead to positive resilience outcomes and the reduction of risks
Communication Practices And Social Media Usage By Government Agencies And Citizens During Post-Disaster Reconstruction
Communication is an essential element in the preparation for, response to and recovery from disasters. Although rapid advancement of new information technologies over the last decade has fuelled academic and practitioners’ interest, there has been little research on disaster communications and the role of social media during the long-term post-disaster reconstruction phase (PDR). The originality of this research rests in the fact that it seeks to build theoretical and empirical knowledge about recovery communication processes by government agencies and citizens, which encompass social media- mediated communications. Building on a naturalistic paradigm and a communication ecology perspective, in-depth analyses were conducted in two post-disaster settings: the earthquakes of 2012 in Emilia-Romagna, Italy, and the Canterbury, New Zealand, earthquake of 2011. Various dimensions were factored into the analysis that encompassed the communication system (i.e. sender and receiver of recovery information, channels, targets and potential noises), the specifics of the reconstruction contexts and the culture in which communication activities took place. A mixture of qualitative and quantitative methodology was applied. Once within-case analysis was completed, the findings from the two studies were compared in order to identify common regularities. The comparison revealed that influential factors of recovery communications and social media uses are related to cultural, contextual, social and individual domains but that some practices can be attributed to the demands and peculiarities of the PDR phase. They can therefore potentially be extended to different reconstruction settings. A set of theoretical propositions was derived from the cross-cases comparison and from the interpretation of empirical evidences in the light of academic literature. At the end of the thesis, propositions are organised within a general theoretical framework that outlines characteristics of the communication processes and social media usage during PDR. This dissertation concludes with two models that serve as a thinking tool to guide government officers and citizens in building effective two-way dialogue after disasters
Boundary quantum critical phenomena with entanglement renormalization
We extend the formalism of entanglement renormalization to the study of
boundary critical phenomena. The multi-scale entanglement renormalization
ansatz (MERA), in its scale invariant version, offers a very compact
approximation to quantum critical ground states. Here we show that, by adding a
boundary to the scale invariant MERA, an accurate approximation to the critical
ground state of an infinite chain with a boundary is obtained, from which one
can extract boundary scaling operators and their scaling dimensions. Our
construction, valid for arbitrary critical systems, produces an effective chain
with explicit separation of energy scales that relates to Wilson's RG
formulation of the Kondo problem. We test the approach by studying the quantum
critical Ising model with free and fixed boundary conditions.Comment: 8 pages, 12 figures, for a related work see arXiv:0912.289
Influence of Topological Edge States on the Properties of Al/Bi2Se3/Al Hybrid Josephson Devices
In superconductor-topological insulator-superconductor hybrid junctions, the
barrier edge states are expected to be protected against backscattering, to
generate unconventional proximity effects, and, possibly, to signal the
presence of Majorana fermions. The standards of proximity modes for these types
of structures have to be settled for a neat identification of possible new
entities. Through a systematic and complete set of measurements of the
Josephson properties we find evidence of ballistic transport in coplanar
Al-Bi2Se3-Al junctions that we attribute to a coherent transport through the
topological edge state. The shunting effect of the bulk only influences the
normal transport. This behavior, which can be considered to some extent
universal, is fairly independent of the specific features of superconducting
electrodes. A comparative study of Shubnikov - de Haas oscillations and
Scanning Tunneling Spectroscopy gave an experimental signature compatible with
a two dimensional electron transport channel with a Dirac dispersion relation.
A reduction of the size of the Bi2Se3 flakes to the nanoscale is an unavoidable
step to drive Josephson junctions in the proper regime to detect possible
distinctive features of Majorana fermions.Comment: 11 pages, 14 figure
Rashba-control for the spin excitation of a fully spin polarized vertical quantum dot
Far infrared radiation absorption of a quantum dot with few electrons in an
orthogonal magnetic field could monitor the crossover to the fully spin
polarized state. A Rashba spin-orbit coupling can tune the energy and the spin
density of the first excited state which has a spin texture carrying one extra
unit of angular momentum. The spin orbit coupling can squeeze a flipped spin
density at the center of the dot and can increase the gap in the spectrum.Comment: 4 pages, 5 figure
Hyperbolic Deformation on Quantum Lattice Hamiltonians
A group of non-uniform quantum lattice Hamiltonians in one dimension is
introduced, which is related to the hyperbolic -dimensional space. The
Hamiltonians contain only nearest neighbor interactions whose strength is
proportional to , where is the lattice index and where
is a deformation parameter. In the limit the
Hamiltonians become uniform. Spacial translation of the deformed Hamiltonians
is induced by the corner Hamiltonians. As a simple example, we investigate the
ground state of the deformed Heisenberg spin chain by use of the
density matrix renormalization group (DMRG) method. It is shown that the ground
state is dimerized when is finite. Spin correlation function show
exponential decay, and the boundary effect decreases with increasing .Comment: 5 pages, 4 figure
Scaling of entanglement support for Matrix Product States
The power of matrix product states to describe infinite-size
translational-invariant critical spin chains is investigated. At criticality,
the accuracy with which they describe ground state properties of a system is
limited by the size of the matrices that form the approximation. This
limitation is quantified in terms of the scaling of the half-chain entanglement
entropy. In the case of the quantum Ising model, we find with high precision. This result can be understood as the emergence of an
effective finite correlation length ruling of all the scaling
properties in the system. We produce five extra pieces of evidence for this
finite- scaling, namely, the scaling of the correlation length, the
scaling of magnetization, the shift of the critical point, and the scaling of
the entanglement entropy for a finite block of spins. All our computations are
consistent with a scaling relation of the form ,
with for the Ising model. In the case of the Heisenberg model, we
find similar results with the value . We also show how
finite- scaling allow to extract critical exponents. These results are
obtained using the infinite time evolved block decimation algorithm which works
in the thermodynamical limit and are verified to agree with density matrix
renormalization group results.Comment: A new section comparing with previous results. Published version
(small differences due to proof corrections
Human peopling of Italian intramontane basins: The early Middle Pleistocene site of Pagliare di Sassa (L’Aquila, central Italy)
Multidisciplinary investigations at Pagliare di Sassa (L’Aquila, central Italy) suggest that the local
succession accumulated from the late Early to the early Middle Pleistocene in a lacustrine environment.
In the upper part, clastic sediments are part of an alluvial fan prograding into the lake, grading to
a braided fluvial system. The pollen record confirms that a significant glacial phase occurred just before
the onset of the Jaramillo inversion. These data, coupled with evidence from the nearby but earlier
Madonna della Strada sequence, allow reconstruction of part of the environmental evolution of L’Aquila
basin before the Jaramillo Subchron. The mammal species of Pagliare di Sassa include Stephanorhinus
hundsheimensis, mostly of open environments, already present at Madonna della Strada. The faunal
turnover characterizing the Early to Middle Pleistocene transition is indicated by the appearances of taxa
typical of the Italian early to middle Galerian faunas, such as Praemegaceros verticornis, together with
Megaloceros savini. The occurrence of Mimomys savini together with Microtus ex gr. Microtus hintonigregaloides
suggests that this assemblage is earlier than the Isernia La Pineta fauna. A flint implement and
a fragmentary herbivore femur with impact scars probably linked to human activity give evidence of the
human peopling of intramontane basins of the Apennine chain since the early Middle Pleistocene.Published170-1782.2. Laboratorio di paleomagnetismoJCR Journalrestricte
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