44 research outputs found
Optimizing Nozzle Travel Time in Proton Therapy
Proton therapy is a cancer therapy that is more expensive than classical radiotherapy but that is considered the gold standard in several situations. Since there is also a limited amount of delivering facilities for this techniques, it is fundamental to increase the number of treated patients over time. The objective of this work is to offer an insight on the problem of the optimization of the part of the delivery time of a treatment plan that relates to the movements of the system. We denote it as the Nozzle Travel Time Problem (NTTP), in analogy with the Leaf Travel Time Problem (LTTP) in classical radiotherapy. In particular this work: (i) describes a mathematical model for the delivery system and formalize the optimization problem for finding the optimal sequence of movements of the system (nozzle and bed) that satisfies the covering of the prescribed irradiation directions; (ii) provides an optimization pipeline that solves the problem for instances with an amount of irradiation directions much greater than those usually employed in the clinical practice; (iii) reports preliminary results about the effects of employing two different resolution strategies within the aforementioned pipeline, that rely on an exact Traveling Salesman Problem (TSP) solver, Concorde, and an efficient Vehicle Routing Problem (VRP) heuristic, VROOM
Towards a permanent deep sea observatory,: the GEOSTAR European Experiment.
GEOSTAR is the prototype of the first European long-term, multidisciplinary deep sea observatory for continuous monitoring of geophysical, geochemical and oceanographic parameters. Geostar is the example of a strong synergy between science and tecnology addressed to the development of new technological solutions for the observatory realisation and management. The GEOSTAR system is described outlining the enhancements introduced during five years of project activity. An example of data retrieved from the observatory being the deep sea mission running is also given.Published111-1202.5. Laboratorio per lo sviluppo di sistemi di rilevamento sottomarinireserve
GEOSTAR, an observatory for deep sea geophysical and oceanographic researches: characteristics, first scientific mission and future activity
GEOSTAR (GEophysical and Oceanographic STation for Abyssal Research) is a project funded by in the 4th Framework Programme of the European Commission, with the aim of developing an innovative deep sea benthic observatory capable of carrying out long-term (up to 1 year) scientific observations at abyssal depths.
The configuration of the observatory, conceived to be a node of monitoring networks, is made up of two main subsystems: the Bottom Station, which in addition to the acquisition and power systems and all the sensors also hosts the communications systems; and the Mobile Docker, a dedicated tool for surface-assisted deployment and recovery. At present the Bottom Station is equipped with a triaxial broad-band seismometer, two magnetometers (fluxgate and scalar), CTD, transmissometer, ADCP, but it can easily host other sensors for different experiments.
The first phase of the project, started in November 1995, was concluded with the demonstration mission in Adriatic Sea at shallow water depth (42 m) in August - September 1998. Some preliminary results of this first scientific experiment are presented and discussed. The second phase, started in 1999, will end with a long-term deep sea scientific mission, scheduled during 2000 for 6-8 months at 3400 m.w.d. in the southern Tyrrhenian bathyal plain.Published491-4973A. Ambiente MarinoN/A or not JCRrestricte
Mission results from the first GEOSTAR observatory (Adriatic Sea, 1998)
We assess the first mission of the GEOSTAR (GEophysical and Oceanographic STation for Abyssal Research)
deep-sea multidisciplinary observatory for its technical capacity, performance and quality of recorded data. The
functioning of the system was verified by analyzing oceanographic, seismological and geomagnetic measurements.
Despite the mission’s short duration (21 days), its data demonstrated the observatory’s technological reliability and
scientific value. After analyzing the oceanographic data, we found two different regimes of seawater circulation
and a sharp and deepening pycnocline, linked to a down-welling phenomenon. The reliability of the magnetic
and seismological measurements was evaluated by comparison with those made using on-land sensors. Such
comparison of magnetic signals recorded by permanent land geomagnetic stations and GEOSTAR during a “quiet”
day and one with a magnetic storm confirmed the correct functioning of the sensor and allowed us to estimate
the seafloor observatory’s orientation. The magnitudes of regional seismic events recorded by our GEOSTAR
seismometer agreed with those computed from land stations. GEOSTAR has thus proven itself reliable for
integrating other deep-sea observation systems, such as modular observatories, arrays, and instrumented submarine
cablesPublished361-373ope
The new Checklist of the Italian Fauna: marine Mollusca.
The mollusc fauna of the Mediterranean Sea is still considered as the best-known marine mollusc fauna in the world. The previous modern checklists of marine Mollusca were produced by joint teams of amateurs and professionals. During the last years the Italian Society of Malacology (Società Italiana di Malacologia – S.I.M.) maintained an updated version of the Mediterranean checklist, that served as the backbone for the development of the new Italian checklist. According to the current version (updated on April 1st, 2021), 1,777 recognised species of marine molluscs are present in the Italian Economic Exclusive Zone, including also the Tyrrhenian coasts of Corsica and the continental shelf of the Maltese archipelago. The new checklist shows an increase of 17% of the species reported in the 1995 Checklist. This is largely (yet not solely) due to the new wave of studies based on Integrative Taxonomy approaches. A total of 135 species (7.6%) are strictly endemic to the Italian waters; 44 species (2.5%) are alien and correspond to the 28% of the Mediterranean alien marine molluscs. All eight extant molluscan classes are represented. The families represented in the Italian fauna are 307, an increase of 14.6% from the first checklist, partly due to new records and partly to new phylogenetic systematics. Compared with the whole Mediterranean malacofauna, the Italian component represents 71% in species and 61% in families, which makes it a very remarkable part of the Mediterranean fauna
European Seafloor Observatory Offers New Possibilities For Deep Sea Study
The Geophysical and Oceanographic Station for Abyssal Research (GEOSTAR), an autonomous seafloor observatory that collects measurements benefiting a number of disciplines during missions up to 1 year long, will begin the second phase of its first mission in 2000. The 6-8 month investigation will take place at a depth of 3400 m in the southern Tyrrhenian basin of the southern Tyrrhenian basin of the central Mediterranean.
GEOSTAR was funded by the European Community (EC) for 2 million (US dollars), will carry equipment for chemical, biological and isotopic analyses not used in the first phase, which will broaden the data collection effort.Published45, 48-492.5. Laboratorio per lo sviluppo di sistemi di rilevamento sottomariniN/A or not JCRreserve
MABEL: a Multidisciplinary Benthic Laboratory for Deep Sea, Long-Term Monitoring in the Antarctic
Multidisciplinary Benthic Laboratory for Deep Sea, Long-Term Monitoring in the AntarcticPublished115-1181.8. Osservazioni di geofisica ambientaleope
Science-Technology Synergy for Research in the Marine Environment: Challenges for the XXI Century
Publishedope
La Magnitudo macrosismica come funzione di I0 e di h. Relazioni proposte per 9 settori principali dell'Area Italiana.
La ricerca vuol essere un ulteriore contributo per una migliore conoscenzadella sismicità in Italia. In particolare si propone di migliorare datigià acquisiti circa la correlazione esistente tra Magnitudo e Intensità deiterremoti, introducendo nella relazione anche un parametro di profonditàvariabile entro cinque intervalli principalih 4
The new <<Catalogue of Strong Italian Earthquakes>>
We describe a new catalogue of strong ltalian earthquakes that the Istituto Nazionale di Geofisica in collaboration
with SGA, has recently made available to the international scientific community and to the general public.
The new catalogue differs from previous efforts in that for each event the usual seismic parameters are complemented
by a list of intensity rated localities, a complete list of relevant references, a series of synoptic comments
describing different aspects of the earthquake phenomenology. and in most cases even the text of the
original written sources. The printed part of the catalogue has been published as a special monograph which
contains also a computer version of the full database in the form of a CD-ROM. The software package includes
a computer program for retrieving, selecting and displaying the catalogue data