16,075 research outputs found
Technological requirements for solutions in the conservation and protection of historic monuments and archaeological remains
Executive summary: This Study has discovered many achievements associated with European support for
scientific and technological research for the protection and conservation of cultural
heritage. The achievements to date are:
1. Creation of an active research community
2. A body of research of unparalleled and enviable international quality and character
3. Ongoing effectiveness of research beyond initial funding
4. Substantial rate of publication
5. Imaginative tools of dissemination and publication
6. Clear spin-offs and contribution to European competitiveness often going outside
the European cultural heritage area
7. Contribution to emerging European legislation, for example, air quality
management.
The Study has also uncovered important research gaps associated with this field that have
yet to begin to be investigated. It has also discovered the need for continuing fine scale
advancement in areas where researchers have been active for a number of years. The
overall picture is that European research in the field of cultural heritage protection must be
put on a secure footing if it is to maintain its commanding lead over other regions of the
world.
This Study concludes that:
1. It would be invidious to attempt to separate basic and applied research in this area
of research. Like any other scientific endeavour, this field needs to integrate basic
and applied research if it is to continue to thrive.
2. Small, flexible, focused interdisciplinary teams responsive to European needs, must
be sustained, promoted and celebrated as models of sustainability and that what is
proposed under the European Research Area (ERA) for large and complex
research projects, could inflict serious damage on this area of research.
3. Resources cannot be delegated to Member States because of the interdisciplinary
nature of cultural heritage and the need for a co-ordinated pan-European
perspective across this research that helps to define the essential character of
European cultural heritage. National programmes only serve local needs, leading
to loss of strategic output, lessening of competitiveness and risk of duplication.
4. A mechanism needs to be created to help researchers working in this field to
communicate and exchange information with related sectors such as construction,
urban regeneration, land reclamation and agriculture.
5. There is overwhelming agreement over the need for sustainable research funding
for cultural heritage and for an iterative process of exchange among researchers,
decision-makers and end-users in order to maximize benefits from project
inception through to dissemination, audit and review.
For all the reasons mentioned above, the most significant recommendation in this Report is
the identification of the need for a European Panel on the Application of Science for Cultural Heritage (EPASCH)
Planetary landing: modelling and control of the propulsion descent
In the propulsive phase, after parachute release, of planetary landing like Mars or Moon, horizontal motion is obtained by tilting the axial thrust, so that it aligns either to the negative velocity vector (gravity turn) or to the requested acceleration vector. The latter strategy is assumed here, as it allows pinpoint landing. As such, tilt angles (pitch and yaw) become proportional to the horizontal acceleration. Instead of designing a hierarchical guidance and control in which horizontal acceleration becomes the attitude control target, a unique control system can be designed based on the fourth order dynamics from angular acceleration to position. The paper shows that the combined dynamics can be (quasi) input-state linearized except the nonlinear factor of the tilt angles (the axial thrust imposed by vertical braking). The paper shows that control design around the reference trajectory (tilt and position) given by the guidance can exploit the quasi linearization, but tracking error stability must be proved in presence of a not stabilizable external disturbance. The paper is restricted to closed-loop control strategies, and their effectiveness is proved through Monte Carlo simulations
A mixed-motives model of private transfers with subjectively-assessed recipient need: Evidence from a poor, transfer-dependent economy
We extend the mixed-motives model of transfer derivatives developed by Cox et al (2004) introducing subjectively-assessed recipient need in place of an absolute income threshold at which the donorâs dominant motive switches from altruism to exchange. This refinement provides a theoretically justifiable threshold amenable to empirical measurement. We test the extended model with customized survey data from Tonga and find evidence consistent with Cox et al in support of altruism for households below the threshold, but, we also find a positive, exchange-motivated relationship for those above the threshold. We conclude that either crowding-out or crowding-in of private transfers can occur when the recipientâs welfare improves, depending on the householdâs pre-transfer welfare level. This also has implications for the distributional impact of private transfers and could explain why poverty reduction can be accompanied by increased income inequality. JEL classification: D13; D64; F24; H55; I30; O15
Remittances and subjective welfare in a mixed-motives model: Evidence from Fiji
To analyze migrantsâ remittance motivations we extend the mixed-motives model of private transfers developed by Cox et al (2004), incorporating subjectively-assessed recipient welfare. We test the model with customized survey data from Fiji, finding evidence supportive of altruism for households below a subjective threshold level, indicating that international migrantsâ remittances provide important social protection coverage to households where formal social protection systems are lacking.Unlike previous studies, we also find a positive, exchange-motivated relationship for those above the threshold. The conventional linear model applied to the same sample uncovers neither relationship. We conclude that either crowding-out or crowding-in of remittances can occur when recipientsâ welfare improves, depending on the householdâs pre-transfer welfare level. The net effects of recipientsâ welfare improvements on remittances, and the effects of remittances on poverty alleviation and income distribution, are consequently more complex and ambiguous than previous studies suggest
An effective theory of accelerated expansion
We work out an effective theory of accelerated expansion to describe general
phenomena of inflation and acceleration (dark energy) in the Universe. Our aim
is to determine from theoretical grounds, in a physically-motivated and model
independent way, which and how many (free) parameters are needed to broadly
capture the physics of a theory describing cosmic acceleration. Our goal is to
make as much as possible transparent the physical interpretation of the
parameters describing the expansion. We show that, at leading order, there are
five independent parameters, of which one can be constrained via general
relativity tests. The other four parameters need to be determined by observing
and measuring the cosmic expansion rate only, H(z). Therefore we suggest that
future cosmology surveys focus on obtaining an accurate as possible measurement
of to constrain the nature of accelerated expansion (dark energy and/or
inflation).Comment: In press; minor changes, results unchange
Using Critical Integrative Argumentation to Assess Socioscientific Argumentation Across Decision-Making Contexts
Socioscientific issues (SSI) are often used to facilitate studentsâ engagement in multiple scientific practices such as decision-making and argumentation, both of which are goals of STEM literacy, science literacy, and integrated STEM education. Literature often emphasizes scientific argumentation over socioscientific argumentation, which involves considering social factors in addition to scientific frameworks. Analyzing studentsâ socioscientific arguments may reveal how students construct such arguments and evaluate pedagogical tools supporting these skills. In this study, we examined studentsâ socioscientific arguments regarding three SSI on pre- and post-assessments in the context of a course emphasizing SSI-based structured decision-making. We employed critical integrative argumentation (CIA) as a theoretical and analytical framework, which integrates arguments and counterarguments with stronger arguments characterized by identifying and refuting counterarguments. We hypothesized that engaging in structured decision-making, in which students integrate multidisciplinary perspectives and consider tradeoffs of various solutions based upon valued criteria, may facilitate studentsâ development of integrated socioscientific arguments. Findings suggest that studentsâ arguments vary among SSI contexts and may relate to studentsâ identities and perspectives regarding the SSI. We conclude that engaging in structured decision-making regarding personally relevant SSI may foster more integrated argumentation skills, which are critical to engaging in information-laden democratic societies
The effective Lagrangian of dark energy from observations
Using observational data on the expansion rate of the universe (H(z)) we
constrain the effective Lagrangian of the current accelerated expansion. Our
results show that the effective potential is consistent with being flat i.e., a
cosmological constant; it is also consistent with the field moving along an
almost flat potential like a pseudo-Goldstone boson. We show that the potential
of dark energy does not deviate from a constant at more than 6% over the
redshift range 0 < z < 1. The data can be described by just a constant term in
the Lagrangian and do not require any extra parameters; therefore there is no
evidence for augmenting the number of parameters of the LCDM paradigm. We also
find that the data justify the effective theory approach to describe
accelerated expansion and that the allowed parameters range satisfy the
expected hierarchy. Future data, both from cosmic chronometers and baryonic
acoustic oscillations, that can measure H(z) at the % level, could greatly
improve constraints on the flatness of the potential or shed some light on
possible mechanisms driving the accelerated expansion. Besides the above
result, it is shown that the effective Lagrangian of accelerated expansion can
be constrained from cosmological observations in a model-independent way and
that direct measurements of the expansion rate H(z) are most useful to do so.Comment: 9 pages, 3 figures, JCAP submitted. This paper presents a
reconstruction of the dark energy potential. It is a companion to Moresco et
al. 2012a, which presents new H(z) results and Moresco et al. 2012b, which
provides cosmological parameter constraint
Gas Kinematics and Excitation in the Filamentary IRDC G035.39-00.33
Some theories of dense molecular cloud formation involve dynamical
environments driven by converging atomic flows or collisions between
preexisting molecular clouds. The determination of the dynamics and physical
conditions of the gas in clouds at the early stages of their evolution is
essential to establish the dynamical imprints of such collisions, and to infer
the processes involved in their formation. We present multi-transition 13CO and
C18O maps toward the IRDC G035.39-00.33, believed to be at the earliest stages
of evolution. The 13CO and C18O gas is distributed in three filaments
(Filaments 1, 2 and 3), where the most massive cores are preferentially found
at the intersecting regions between them. The filaments have a similar
kinematic structure with smooth velocity gradients of ~0.4-0.8 km s-1 pc-1.
Several scenarios are proposed to explain these gradients, including cloud
rotation, gas accretion along the filaments, global gravitational collapse, and
unresolved sub-filament structures. These results are complemented by HCO+,
HNC, H13CO+ and HN13C single-pointing data to search for gas infall signatures.
The 13CO and C18O gas motions are supersonic across G035.39-00.33, with the
emission showing broader linewidths toward the edges of the IRDC. This could be
due to energy dissipation at the densest regions in the cloud. The average H2
densities are ~5000-7000 cm-3, with Filaments 2 and 3 being denser and more
massive than Filament 1. The C18O data unveils three regions with high CO
depletion factors (f_D~5-12), similar to those found in massive starless cores.Comment: 20 pages, 14 figures, 6 tables, accepted for publication in MNRA
Cosmic magnetic fields and dark energy in extended electromagnetism
We discuss an extended version of electromagnetism in which the usual gauge
fixing term is promoted into a physical contribution that introduces a new
scalar state in the theory. This new state can be generated from vacuum quantum
fluctuations during an inflationary era and, on super-Hubble scales, gives rise
to an effective cosmological constant. The value of such a cosmological
constant coincides with the one inferred from observations as long as inflation
took place at the electroweak scale. On the other hand, the new state also
generates an effective electric charge density on sub-Hubble scales that
produces both vorticity and magnetic fields with coherent lengths as large as
the present Hubble horizon.Comment: 4 pages, 2 figures. Contribution to the proceedings of Spanish
Relativity Meeting 2010, Granada, Spain, 6-10 September 201
Wealthy and healthy in the South Pacific
Objectives: The main aim of this paper is to analyse the relationship between socio-economic status and health status at the household level in Fiji, a developing country in the South Pacific, based on original household survey data compiled by the authors. Method: We exploit the geographic conditions of Viti Levu, the relatively small main island of Fiji, to isolate the effects of household wealth on health. For households on this island physical distance is not a significant impediment for access to health care and other publicly-provided services. We use a constructed index of household wealth in place of the more commonly used income measure of socio-economic status. To control for reverse causality and other possible sources of endogeneity we use an Instrumental Variable strategy in the regression analysis. Findings: We find that a householdâs socio-economic status, as measured by a constructed wealth index, has a substantial impact on the householdâs health status. We estimate that if a household's wealth increased from the minimum to the maximum level, this would decrease its probability of being afflicted by an incapacitating illness by almost 50 per cent. Conclusions: Health outcomes from existing health services can therefore be improved by raising the economic well-being of poor households. Conversely, the provision of additional health services alone may not necessarily improve health outcomes for the poorest
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