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POSCRITTO 2012 - UNA PRIMA SINOSSI
No full textIL POSCRITTO SEGUE I VOLUMI DI TESI, ANALISI E SINTESI DELLE DINAMICHE DOMINANTI DELL'AGIRE E DELL'AGIRE SOCIALE. SI TRATTA DI UNA PRIMA FORMA SINOTTICA DELLA TEORIA DEI VALORI (TdV) NONCHE' DI ALCUNI ASPETTI DEL SUO SVILUPPO E APPLICAZIONE
LA CRISTALLIZZAZIONE DEI DEBITI TRIBUTARI NELL'AMBITO DELLA TRANSAZIONE FISCALE: IL PROBLEMA DEGLI EFFETTI "TIPICI" DELL'ISTITUTO DI CUI ALL'ART. 182TER DEL R.D. N. 267/1942
No full textInterazione tra correnti di pendio ed isola urbana di calore
No full textAn experimental study about two-dimensional upslope and downslope flows in a stably stratified environment and about their interaction with an urban heat island placed in a valley is presented. Two different configurations are reconstructed in a laboratory model: an open valley at the bottom of a slope and a valley closed between two symmetric slopes. The slope flows are generated heating or cooling the slopes by Peltier cells. The urban heat island is simulated by an electric resistance placed within the valley. The main features of the circulation driven by the thermal exchanges are studied using an image analysis technique, named Feature Tracking, that allows a Lagrangian reconstruction of the motion. The distributions of the velocity and of its second order statistics along some profiles are displayed; the temperature profiles are obtained from measurements with thermocouples. The experimental tests display that the slope flows affect strongly the urban heat islands in both configurations: in the open valley the urban heat island is strongly deformed and nearly destroyed by the slope flow and a recirculating zone takes place; in the closed valley the urban heat island circulation is weakened by the anabatic flows and it is enhanced by the katabatic flows.The text of the work is composed by 5 chapters: 1) Introductory description of the anabatic and katabatic flows and of the urban heat island as phenomena of the atmospheric boundary layer, with several references to the state of art; 2) Detailed description of the experimental setup and procedures; 3) Presentation of the experimental results; 4) Comparison between some results of this work an the results of other works; 5) Main conclusions of the study
ASPETTI CRITICI NELLO STUDIO DEL PARTICOLATO ATMOSFERICO:VALUTAZIONE DEL COMPORTAMENTO DELLE SPECIE SEMIVOLATILI E CONTRIBUTO NANOPARTICELLARE DEGLI ELEMENTI
No full textSome problems concerning the pseudoeffective cone of blown-up surfaces and projectivized vector bundles
No full textWe discuss a couple of problems concerning the pseudoeffective cone of a projective variety. In the first part we deal with the influence of a generalization of the Segre Conjecture on the Mori cone of a blown-up surface. In the second part we prove the existence of a weak Zariski decomposition for the pseudoeffective divisors of a number of projectivized vector bundle
L'uso degli ultrasuoni alle frequenze terapeutiche: studio degli effetti indotti in linee cellulari utilizzando spettroscopia FTIR e microscopia
No full textTheoretical underpinnings and empirical evidence for a new approach to vulnerability to poverty
No full textThe present research analyzes the debate on the link between risk and future welfare presenting the theoretical underpinning of a new sound empirical framework for measuring vulnerability to poverty. It demonstrates that uninsured risk reduces household's well-being for the more exposed subsets of the population through its impact on the "ex-ante" household's behavior. Challenging the common view that looks at the coping and managing strategies as an optimal "ex-ante" behavior to reduce the potentially harmful consequences of risk, this work demonstrates (theoretically and empirically) that the risk-induced changing behavior actually has a cost in terms of welfare, especially for poor households in developing contexts. If it is the case, current monetary approaches to vulnerability to poverty lead to bias poverty prevention recommendation
Sistemi informativi integrati per la valorizzazione del patrimonio urbano-architettonico, tra 3D GIS, AIS e Web
No full textCurrently in the field of management,
enhancement, territory and cultural heritage
analysis, two types of information systems offer significant tools: GIS (Geographic Information System) and AIS (Architectural Information System). The first one manages urban and territorial scale data, the second one administers architectural scale data.
For a complete management and analysis of
heritage both scales (territorial-urban and
architectural) are essential but despite
numerous attempts made in recent years,
currently no system is really able to manage
them simultaneously.
After a thorough analysis of both types of
systems, and a careful study on the state of the art, this study aims to create a hybrid system, which is a new interface that allows to simultaneously view an AIS, a GIS and a window for management of spatial queries.
Considering the deep differences between the two systems, the ultimate goal is to integrate them by proposing a new hybrid system (HS) to solve the problem of scale change (from analysis to synthesis) using a new data structure and a new interface.
To achieve the ultimate goal have been studied mainly:
- the possibilities of implementation of the two systems;
- spatial analysis and 3D topology
VADASE: Variometric Approach for Displacement Analysis Stand-alone Engine
No full textGlobal Navigation Satellite Systems (GNSS), like Global Positioning System (GPS), are nowadays very well known. Besides the mass market, GPS plays an important role in several technical and scientific activities. Ever since the early stages of development (mid 1980s), given the high level of accuracy achieved in determining the coordinates of the receiver, it became clear that the extensive deployment of GPS stations all over the world would have improved many tasks in geodesy and geodynamics.
In recent years, several studies have demonstrated the effective use of GPS in estimating coseismic displacement waveforms induced by an earthquake with accuracies ranging from a few millimeters to a few centimeters (so called GPS seismology). This contribution is particularly relevant as it supports the estimation of important seismic parameters (e.g. seismic moment and magnitude Mw) without the problems of saturation that commonly affect seismometers and accelerometers close to large earthquakes. These studies were developed mainly off-line, analyzing observations acquired during strong earthquakes. Then, well-known processing strategies (single Precise Point Positioning (PPP), and differential positioning) have been developed to reduce as far as possible the latency between earthquake occurrence and coseismic displacement waveforms estimation.
This work describes a new approach that was originally designed to detect the 3D displacements of a single GPS receiver in real-time and that was eventually appointed as an effective strategy to contribute to GPS seismology. The main goals that guided through the development aimed to obtain the coseismic displacement waveforms in real-time and using a single receiver. In particular, it was pursued to overcome the drawbacks of the two most common strategies used so far in GPS seismology: PPP uses a single receiver, but it requires ancillary products (e.g. information regarding satellites orbits, clocks; parameters describing the Earth orientation with respect to an external inertial system) currently unavailable in real-time. On the other hand, differential kinematic positioning is based on a complex infrastructure (GPS permanent network), which has to be managed by specialized research centers to obtain high accuracies in real-time.
The new approach proposed in this work, named Variometric Approach for Displacement Analysis Stand-alone Engine (VADASE), is based upon a so called variometric algorithm, which is able to use a single receiver to obtain real-time results, with accuracies ranging from few centimeters up to a couple of decimeters.
In order to prove the feasibility of the variometric algorithm, a tuned software, which was appointed with the same name (i.e. VADASE), was implemented. Exploiting this software to process a large amount of both simulated and real data, the main advantages of VADASE, as well as its limitations, were investigated in details.
At a first stage, VADASE effectiveness was proven on a simulated example. First, a known displacement (1 cm East and North and 2 cm Up) was synthetically introduced into carrier phase observations collected at 1 Hz rate by the M0SE permanent GPS station (Rome, Italy). Then, these data were processed using the variometric algorithm: the displacements were estimated with an accuracy of 1-2 mm in the horizontal and the vertical directions. The solutions obtained using the GPS broadcast products available in real-time and the best quality products supplied by IGS a posteriori displayed a global agreement of 1 mm for the horizontal components and 2 mm for the height.
Given this fundamental proof of success, and provided that the variometric algorithm was originally
conceived to contribute in the field of GPS seismology and tsunami warning systems, VADASE was applied to retrieve the coseismic displacements and the waveforms generated by real earthquakes. Here, it is worth underlining that all VADASE results were obtained using exclusively broadcast products that are available in real-time. The most significant outcomes were obtained by considering data collected at 1 Hz rate from the IGS station of BREW during the Denali Fault, Alaska earthquake (Mw 7.9, November 3, 2002), at 10 Hz rate from CADO station during the L'Aquila earthquake (Mw 6.3, April 6, 2009), and at 5 Hz rate from some stations included in the UNAVCO - PBO network during the Baja, California earthquake (Mw 7.2, April 4, 2010). In all cases, the agreement between VADASE and other solutions achieved by different research groups employing different methodologies was between few centimeters and a couple of decimeters.
The real-time potentialities of the variometric approach were internationally recognized during the recent tremendous earthquake in Japan (Mw = 9.0, March 11, 2011), when the GNSS research team of University of Rome "La Sapienza" was able to provide the first waveforms results among the scientific community. The results obtained for IGS stations of MIZU, USUD and from EV-network station JA01 were compared with those stemming from the PPP approach implemented in the software developed at Natural Resources Canada (NRCan). This work was made possible thanks to the precious support of Dr. Henton Joe and Dr. Dragert Herb, NRCan, who produced the PPP solutions for the aforementioned stations. The agreement between VADASE and PPP was evaluated in terms of the RMSE of the differences.
In addition, it was investigated the agreement reliance with the earthquake duration. The Root Mean Square Error (RMSE) of the differences between the two solutions ranged from 0.01-0.02 m in East and North and 0.06 m in Up, after one minute, to approximately 0.05 m in East and North and (with much larger variability) 0.20 m in Up after four minutes. Further, the agreement between the two approaches evaluated in terms of peak to peak displacements appeared to be independent from the earthquake duration. In details, the differences reached approximately 0.01 m in East and North and 0.03 m in Up components. Finally, the correlation coefficient between the two solutions proved to be higher than 99% for the planimetric components (but for the East component of USUD and the North component of JA01 which showed 97% and 96% correlations, respectively). The vertical component showed slightly lower (and with larger variability) correlations: 65%, 84% and 90% for stations MIZU, USUD and JA01, respectively.
At the moment of this writing, VADASE is subject of a pending patent of University of Rome “La Sapienza” ever since June 2010. In October 2010 VADASE was recognized as a simple and effective approach towards real-time coseismic displacement waveform estimation and it was awarded the German Aerospace Agency (DLR) Special Topic Prize and the First Audience Award in the European Satellite Navigation Competition 2010