410 research outputs found

    Neapolitan volcanic area Tide Gauge Network (Southern Italy): Ground Displacements and Sea-Level Oscillations

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    Abstract. In this study, we investigate the oscillations of relative sea level through the analysis of tide gauge records about 10-year long collected in the Gulfs of Pozzuoli and Napoli (Southern Italy). The main goal of this study is to provide a suitable resolution model of the sea tides including low frequency (seiches), tidal bands and non-linear tides. The spectral analyses of the tide gauge records lead us to identify a number of seiche periods some of them already known from the literature and some other unknown. Furthermore, we target a non-conventional purpose of the tidal analysis, namely extracting from the tide gauge records the volcano-tectonic signal (vertical ground displacement) in the resurgent Campi Flegrei caldera. We suggest a method to filter out the volcano-tectonic signal (bradyseism) from the tide gauge records by deconvolving it from two records, one collected in the active volcanic area (Pozzuoli) and the other one collected in a tectonically stable station (Napoli), located beyond the caldera rim. Finally, we retrieve the relative mean sea level change in the Gulf of Naples and compare it with the trend found in five tide gauges spread along the Italian coast

    Planning, Delivering, and Evaluating an Extension In-Service Training Program for Developing Local Food Systems: Lessons Learned

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    The social movement focused on re-localizing food systems is oriented toward recreating relationships between producers, consumers, and other community stakeholders. Sustaining community efforts to build local food systems requires preparation of county Extension educators to understand how food supply chains function as systems, facilitate community partnerships, and create equitable access to locally produced food. This paper shares how North Carolina Cooperative Extension designed, delivered, and evaluated a local foods in-service training on these three topics, as well as shares lessons learned through the process. The implications of this study are helpful for Extension educators planning, delivering, and evaluating in-service training programs that support development of local food systems

    Optical production and detection of dark matter candidates

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    The PVLAS collaboration is at present running, at the Laboratori Nazionali di Legnaro of I.N.F.N., Padova, Italy, a very sensitive optical ellipsometer capable of measuring the small rotations or ellipticities which can be acquired by a linearly polarized laser beam propagating in vacuum through a transverse magnetic feld (vacuum magnetic birefringence). The apparatus will also be able to set new limits on mass and coupling constant of light scalar/pseudoscalar particles coupling to two photons by both producing and detecting the hypothetical particles. The axion, introduced to explain parity conservation in strong interactions, is an example of this class of particles, all of which are considered possible dark matter candidates. The PVLAS apparatus consists of a very high finesse (> 140000), 6.4 m long, Fabry-Perot cavity immersed in an intense dipolar magnetic field (~6.5 T). A linearly polarized laser beam is frequency locked to the cavity and analysed, using a heterodyne technique, for rotation and/or ellipticity acquired within the magnetic field.Comment: presented at "Frontier Detectors for Frontier Physics - 8th Pisa Meeting on Advanced Detectors - May 21-27, 2000" to appear in: Nucl.Instr. and Meth.

    S.A.G.NET: Rete GPS dell'Appennino meridionale.

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    The Matese carbonatic massive occupies the northernmost part of the campanian Apennine while Sannio mounts, located to the East of massive, consists primarily of quaternary deposits and represent the area of Apennine chain degrading to East towards the Bradanica foredeep. The area was affected in historical time by several destructive earthquakes. The first ground deformation studies in this area started from 1990-2000 with the definition of geodetic networks, covering all or part of the massive Matese, with the aim of evaluating seismogenic sources responsible for the seismicity of the area. In 2002, a careful inspection of the existing GPS benchmarks was carried out; those which had a good state of preservation and a good level of reliability were included into a new geodetic Matese network, consisting of 38 3D benchmarks. Several surveys were conducted in 2000, 2002 and 2004,with the aim of defining the strain field, defined by plano-altimetric components. In 2005, an intensive work of gathering and validating available data started, integrating data collected by previous surveys with those collected during the new survey carried out in 2006. This work describes in detail the various stages of implementing the final network S.A.G.NET, whose geometry was also bound to the distribution of the known seismogenic sources present in the area. We also show the first results obtained from data collected from2000 to 2006 and the resulting kinematic model for this area

    Organizational learning and emotion: constructing collective meaning in support of strategic themes

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    Missing in the organizational learning literature is an integrative framework that reflects the emotional as well as the cognitive dynamics involved. Here, we take a step in this direction by focusing in depth over time (five years) on a selected organization which manufactures electronic equipment for the office industry. Drawing on personal construct theory, we define organizational learning as the collective re-construal of meaning in the direction of strategically significant themes. We suggest that emotions arise as members reflect on progress or lack of progress in achieving organizational learning. Our evidence suggests that invalidation – where organizational learning fails to correspond with expectations – gives rise to anxiety and frustration, while validation – where organizational learning is aligned with or exceeds expectations – evokes comfort or excitement. Our work aims to capture the key emotions involved as organizational learning proceeds

    La rete GPS dell'isola d'Ischia: Deformazioni del suolo in un'area vulcanica attiva (1998-2010).

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    This work shows the experience acquired by the INGV-Osservatorio Vesuviano GPS Team to study the displacement field at Ischia island. After the last GPS survey, carried out in June 2010, we decided to reorganize and to reprocess the GPS data. The results were integrated with those of the three permanent GPS stations operating on the island. Data quality and repeatability have been evaluated. In order to define the GPS velocity field, we combined multi-year solutions in the period from 1998 to 2010.We defined a local reference system and analyzed the time series for a realistic error estimate. After a description of recent volcanic history and dynamics of Ischia, we describe the data-set, data processing strategy, and finally, some considerations on the achieved results are exposed

    GPS Monitoring at Vesuvio, Campi Flegrei Caldera and Ischia Island (Southern Italy)

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    The Neapolitan volcanic area is located in the southern part of the Campanian plain and includes three active volcanoes (Vesuvius, Campi Flegrei Caldera and Ischia Island). This area shows different dynamical behaviours. Campi Flegrei caldera represents one well known and peculiar example of ground deformations (bradyseism), with periods of intense uplift during the 1969-72 and 1982-84, followed by subsidence phase with some episodic mini-uplifts superimposed. Contrary, Vesuvius is a substantially stable volcano, with small and localized subsidence mainly in the crater zone. Ischia Island has been characterized by subsidence in the S and NW sectors of the island. The presence of these three volcanoes in a dense populated area, makes ground deformation detection a crucial point in the risk mitigation. Ground deformation is an important volcanic precursor, because linked to magma overpressure and migration, thus, continuous monitoring and modelling is one of the main instruments to attempt for a short time forecast of eruptive activity. Since several years, the INGV – Osservatorio Vesuviano installed a permanent GPS network (NeVoCGPS), constituted of 27 stations, in the Neapolitan volcanic area with a configuration that guarantees a continuous and fast 3D information about the dynamics of the area. All the GPS stations are managed by remote control, the data are daily downloaded automatically. After an automatic quality control procedure, the data processing is performed by the Bernese Processing Engine (BPE) of the Bernese GPS software v. 5.0. In this work, the entire chain of data acquisition and processing is described and some results obtained in last years are presented

    Somma Vesuvius volcano: ground deformations from CGPS observations (2001-2012)

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    This paper is a contribution to the evaluation of ground deformations at Somma-Vesuvius volcano by means GPS measurements from 2001 to 2012. In this study we use a dataset from nine continuous GPS stations of the Neapolitan Volcanoes Continuous GPS network (NeVoCGPS), which covers the Neapolitan volcanic area, and is operated by the Istituto Nazionale di Geofisica e Vulcanologia. The GPS data processing is performed by the Bernese software v. 5.0. The results of the data processing show that the dynamics of the Somma-Vesuvio volcano, between 2001 and 2012, is characterized by a general subsidence, with maximum values on the Gran Cono at BKNO (−11.7 ± 0.65 mm/year) and BKE1 (−4.92 ± 0.36 mm/year) stations. The subsidence decrease from the crater down to the coast and the horizontal displacements are concentrated in Gran Cono area, the youngest part of the volcano. The parameters of the principal strain components indicate that Somma-Vesuvius is affected by a predominant contraction phase, which is concentrated in the areas with the greatest altitudes

    AREA VULCANICA NAPOLETANA: 10 ANNI DI OSSERVAZIONI GPS

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    L’area napoletana è una delle zone a più alto rischio vulcanico, per la presenza di tre strutture vulcaniche attive (il Somma-Vesuvio, la caldera dei Campi Flegrei e l’Isola d’Ischia) e per l’intensa urbanizzazione della zona. La concentrazione dei suddetti vulcani attivi in un’area molto urbanizzata rende fondamentale la presenza di un sistema di monitoraggio che registri i fenomeni connessi al processo vulcanico in atto e che dia informazioni utili per modellarne il comportamento. Tra i vari fenomeni che generalmente sono associati ai processi vulcanici, le deformazioni statiche giocano un ruolo importante per lo studio dei parametri delle sorgenti magmatiche e per la loro modellazione. Nell’area vulcanica napoletana è presente una estesa rete GPS (sia permanente che discreta) che negli ultimi 10 anni ha permesso di raccogliere una mole importante di dati e di avere informazioni circa la dinamica in atto. I dati raccolti in tale periodo, a causa dei rapidi sviluppi della tecnologia GPS, della strumentazione, delle metodologie di processamento, presentavano alcune disomogeneità nella qualità, nell’archiviazione e nell’elaborazione. Pertanto è stato necessario un notevole lavoro di verifica, correzione ed omogeneizzazione dal punto di vista qualitativo di tutti i dati disponibili. Successivamente si è potuto procedere al riprocessamento dei dati, utilizzando il software GPS Bernese v. 5.0, secondo i più recenti standard IGS. Questo lavoro ha permesso di creare un database accurato di tutti i dati GPS disponibili per l’intera area vulcanica napoletana e il conseguente miglioramento della qualità dei risultati ha fornito un utile contributo all’interpretazione dei movimenti del suolo avvenuti negli ultimi anni. In particolare, i nuovi dati ottenuti hanno permesso un’accurata descrizione dell’andamento temporale dei modesti fenomeni di sollevamento (mini-uplift) che hanno interessato la caldera flegrea negli ultimi anni
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