15,467 research outputs found
Landslide risk management through spatial analysis and stochastic prediction for territorial resilience evaluation
Natural materials, such as soils, are influenced by many factors acting during their formative and evolutionary process: atmospheric agents, erosion and transport phenomena, sedimentation conditions that give soil properties a non-reducible randomness by using sophisticated survey techniques and technologies. This character is reflected not only in spatial variability of properties which differs from point to point, but also in multivariate correlation as a function of reciprocal distance. Cognitive enrichment, offered by the response of soils associated with their intrinsic spatial variability, implies an increase in the evaluative capacity of the contributing causes and potential effects in failure phenomena. Stability analysis of natural slopes is well suited to stochastic treatment of uncertainty which characterized landslide risk. In particular, this study has been applied through a back- analysis procedure to a slope located in Southern Italy that was subject to repeated phenomena of hydrogeological instability (extended for several kilometres in recent years). The back-analysis has been carried out by applying spatial analysis to the controlling factors as well as quantifying the hydrogeological hazard through unbiased estimators. A natural phenomenon, defined as stochastic process characterized by mutually interacting spatial variables, has led to identify the most critical areas, giving reliability to the scenarios and improving the forecasting content. Moreover, the phenomenological characterization allows the optimization of the risk levels to the wide territory involved, supporting decision-making process for intervention priorities as well as the effective allocation of the available resources in social, environmental and economic contexts
Spitzer Warm Mission Workshop Introduction
The Spitzer Warm Mission Workshop was held June 4–5, 2007, to explore the science drivers for the warm Spitzer mission and help the Spitzer Science Center develop a new science operations philosophy. We must continue to maximize the science return with the reduced resources available, both using (a) the shortest two IRAC channels, and (b) archival research with the rich Spitzer archive. This paper summarizes the overview slides presented to the workshop participant
Smoothed Particle Hydrodynamics Calculations of Stellar Interactions
Smoothed Particle Hydrodynamics is a multidimensional Lagrangian method of
numerical hydrodynamics that has been used to tackle a wide variety of problems
in astrophysics. Here we develop the basic equations of the SPH scheme, and we
discuss some of its numerical properties and limitations. As an illustration of
typical astrophysical applications, we discuss recent calculations of stellar
interactions, including collisions between main sequence stars and the
coalescence of compact binaries.Comment: 21 pages, invited review paper to appear in Journal of Computational
and Applied Mathematics (JCAM). Fig. 2 is available from the authors in
hardcopy form only. Revised, slightly abbreviated versio
CMOS array design automation techniques
The design considerations and the circuit development for a 4096-bit CMOS SOS ROM chip, the ATL078 are described. Organization of the ATL078 is 512 words by 8 bits. The ROM was designed to be programmable either at the metal mask level or by a directed laser beam after processing. The development of a 4K CMOS SOS ROM fills a void left by available ROM chip types, and makes the design of a totally major high speed system more realizable
Economic Outlook Symposium: summary of 2009 results and forecasts for 2010
According to participants in the Chicago Fed’s annual Economic Outlook Symposium, solid economic growth is forecasted for the nation in 2010, following a very sharp contraction during 2008 and the first half of 2009; inflation is expected to increase in 2010; and the unemployment rate is predicted to peak early in 2010 and edge lower throughout the year.
Economy on cruise control in 2010 and 2011
According to participants in the Chicago Fed’s annual Automotive Outlook Symposium, solid economic growth is forecasted for the nation this year and in 2011. Inflation is expected to remain contained, but the unemployment rate is anticipated to remain high. Light vehicle sales are forecasted to improve moderately in 2010 and 2011.Automobiles - Prices ; Inflation (Finance)
RFQD - a Decelerating Radio Frequency Quadrupole for the CERN Antiproton Facility
The RFQD is designed to decelerate antiprotons of momentum 100 MeV/c (kinetic
energy 5.33MeV)down to a kinetic energy variable between ~10 keV and 120 keV.
Inside the RFQ body, at ground potential, the rf structure of the four-rod type
is mounted on insulating supports. It can be biased between plus/minus 60 kV dc
to achieve the continuous adjustment of output energy required by the ASACUSA
experiment at the CERN Antiproton Decelerator AD. The different parts of the
system are described and the present status reported
Changing the University System Management: a study of the Italian scenario
Over recent years, the Italian University System has been handling a phase of deep
changes, which have had significant impact on its mission and on the way it operates.
The most important of these changes have been to the organisation of universities, their
recruitment procedures and in terms of improvements to the quality and efficiency of
the university system itself. In this perspective, the objective of this research was to carry
out a critical analysis of the process of change, with special reference to improving
efficiency by making the transition from cash-based accounting to accrual accounting. In
order to achieve this objective, the starting point was the legislation of reference that
sets out the terms for the move to financial accrual accounting. A comparative analysis
was then carried out at an international level, with the purpose of highlighting the
strengths and weaknesses identified during the implementation of these new
procedures within the public field. This was followed by an analysis of the details of the
theory defining the accounting principles to be used in the process of preparing
university’s financial statements. Finally, the study identified the main critical points
relating to implementation of the new accounting system, offering, at the same time,
several thoughts concerning possible subsequent analyses on this topic
Microlens Parallax Measurements with a Warm Spitzer
Because Spitzer is an Earth-trailing orbit, losing about 0.1 AU/yr, it is
excellently located to perform microlens parallax observations toward the
Magellanic Clouds (LMC/SMC) and the Galactic bulge. These yield the so-called
``projected velocity'' of the lens, which can distinguish statistically among
different populations. A few such measurements toward the LMC/SMC would reveal
the nature of the lenses being detected in this direction (dark halo objects,
or ordinary LMC/SMC stars). Cool Spitzer has already made one such measurement
of a (rare) bright red-clump source, but warm (presumably less oversubscribed)
Spitzer could devote the extra time required to obtain microlens parallaxes for
the more common, but fainter, turnoff sources. Warm Spitzer could observe bulge
microlenses for 38 days per year, which would permit up to 24 microlens
parallaxes per year. This would yield interesting information on the disk mass
function, particularly old brown dwarfs, which at present are inaccessible by
other techniques. Target-of-Opportunity (TOO) observations should be divided
into RTOO/DTOO, i.e., ``regular'' and ``disruptive'' TOOs, as pioneered by the
Space Interferometry Mission (SIM). LMC/SMC parallax measurements would be
DTOO, but bulge measurements would be RTOO, i.e., they could be scheduled in
advance, without knowing exactly which star was to be observed.Comment: 6 pages + 1 Figure, To be presented at The Warm Spitzer Mission
Workshop, 4-5 June 2007, Pasaden
Scattering induced dynamical entanglement and the quantum-classical correspondence
The generation of entanglement produced by a local potential interaction in a
bipartite system is investigated. The degree of entanglement is contrasted with
the underlying classical dynamics for a Rydberg molecule (a charged particle
colliding on a kicked top). Entanglement is seen to depend on the structure of
classical phase-space rather than on the global dynamical regime. As a
consequence regular classical dynamics can in certain circumstances be
associated with higher entanglement generation than chaotic dynamics. In
addition quantum effects also come into play: for example partial revivals,
which are expected to persist in the semiclassical limit, affect the long time
behaviour of the reduced linear entropy. These results suggest that
entanglement may not be a pertinent universal signature of chaos.Comment: Published versio
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