486 research outputs found

    Spectral emissivity and temperature maps of the Solfatara crater from DAIS hyperspectral images

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    Quantitative maps of surface temperature and spectral emissivity have been retrieved on the Solfatara crater at Pozzuoli (Naples) from remote sensing hyperspectral data. The present study relies on thermal infrared images collected on July 27, 1997 by the DAIS hyperspectral sensor owned by the German aerospace center (DLR). The Emissivity Spectrum Normalization method was used to make temperature and emissivity estimates. Raw data were previously transformed in radiance and corrected for the atmospheric contributions using the MODTRAN radiative transfer code and the sensor response functions. During the DAIS flight a radiosonde was launched to collect the atmospheric profiles of pressure, temperature and humidity used as input to the code. Retrieved temperature values are in good agreement with temperature measurements performed in situ during the campaign. The spectral emissivity map was used to classify the image in different geo-mineralogical units with the Spectral Angle Mapper method. Areas of geologic interest were previously selected using a mask obtained from an NDVI image calculated with two channels of the visible (red) and the near infrared respectively

    Spectral emissivity and temperature maps of the Solfatara crater from DAIS hyperspectral images

    Get PDF
    Quantitative maps of surface temperature and spectral emissivity have been retrieved on the Solfatara crater at Pozzuoli (Naples) from remote sensing hyperspectral data. The present study relies on thermal infrared images collected on July 27, 1997 by the DAIS hyperspectral sensor, owned by the German aerospace center (DLR). The Emissivity Spectrum Normalization method was used to make temperature and emissivity estimates. Raw data were previously transformed in radiance and corrected for the atmospheric contributes using the MODTRAN radiative transfer code and the sensor response functions. During the DAIS flight a radiosonde was launched to collect the atmospheric profiles of pressure, temperature and humidity used as input to the code. Retrieved temperature values are in good agreement with temperature measures performed in situ during the campaign. The spectral emissivity map was used to classify the image in different geomineralogical units with the Spectral Angle Mapper method. Areas of geologic interest were previously selected using a mask obtained from an NDVI image calculated with two channels of the visible (red) and the near infrared respectively

    Direct Measures of Path Delays on Commercial FPGA Chips

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    We present a general technique for measuring the propagation delay on the internal wires of FPGA chips. The measure is based on the comparison between the operating frequencies of two ring oscillators that differ only for the structure under test, that is included (or not) in the loop. Experimental results are presented for a device of the Xilinx XC4000 family

    L’utilizzo delle protesi endoscopiche nella patologia dell’apparato digerente

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    L’utilizzo di protesi ad introduzione per via endoscopica per patologie dell’apparato digerente sia benigne che maligne ha avuto negli ultimi anni un considerevole sviluppo. Il posizionamento delle endoprotesi è ben tollerato dai pazienti, non necessita di anestesia e comporta rischi relativamente minimi. Le nuove protesi metalliche autoespansibili permettono di risolvere stenosi anche molto serrate senza quasi mai necessità di dilatazione, con riduzione dei rischi che da questa derivano. Viene riportata una revisione dell’esperienza di protesizzazione per patologie dell’apparato digerente e vengono discussi le indicazioni, i limiti e le complicanze, sulla scorta dei dati dalla letteratura internazionale

    Analyses of TIMS and AVIRIS data, integrated with field and laboratory spectra, for lithological and mineralogical interpretation of Vulcano Island, Italy

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    Vulcano Island is part of the Eolian archipelago, located about 25 km from the northeast coast of Sicily. The archipelago comprises seven major volcanic islands, two of which are active volcanoes (Vulcano and Stromboli). Vulcano covers an area of about 50 square km, and is about 10 km long. Explosive volcanic activity has predominated in the geological evolution of Vulcano Island, and there is no evidence that this pattern has ceased. Rather, the current situation is one of unrest, so a strict regimen of continuous geophysical and geochemical monitoring has been undertaken over the last decade. Though the year-round population of Vulcano is small (under 1000), during the summer the island becomes a very popular resort, and has thousands of additional tourists at any time throughout the high season, thus substantially increasing the number of people potentially at risk from an explosive eruption or other hazards such as noxious gas emissions (e.g., CO2, H2S, SO2). During the past ten years, remote sensing data have been repetitively acquired with optical and microwave airborne sensors. The present work shows the preliminary results of a study based on the integration of various remote sensing data sets with field spectroscopy, and other laboratory analyses, for the geological and geomorphological mapping of the island. It is hoped that such work will also usefully contribute to the evaluation of the volcanic hazard potential of the islands as well as to the evaluation of the status of its current activity

    The gamma-ray burst monitor for Lobster-ISS

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    Lobster-ISS is an X-ray all-sky monitor experiment selected by ESA two years ago for a Phase A study (now almost completed) for a future flight (2009) aboard the Columbus Exposed Payload Facility of the International Space Station. The main instrument, based on MCP optics with Lobster-eye geometry, has an energy passband from 0.1 to 3.5 keV, an unprecedented daily sensitivity of 2x10^{-12} erg cm^{-2}s$^{-1}, and it is capable to scan, during each orbit, the entire sky with an angular resolution of 4--6 arcmin. This X-ray telescope is flanked by a Gamma Ray Burst Monitor, with the minimum requirement of recognizing true GRBs from other transient events. In this paper we describe the GRBM. In addition to the minimum requirement, the instrument proposed is capable to roughly localize GRBs which occur in the Lobster FOV (162x22.5 degrees) and to significantly extend the scientific capabilities of the main instrument for the study of GRBs and X-ray transients. The combination of the two instruments will allow an unprecedented spectral coverage (from 0.1 up to 300/700 keV) for a sensitive study of the GRB prompt emission in the passband where GRBs and X-Ray Flashes emit most of their energy. The low-energy spectral band (0.1-10 keV) is of key importance for the study of the GRB environment and the search of transient absorption and emission features from GRBs, both goals being crucial for unveiling the GRB phenomenon. The entire energy band of Lobster-ISS is not covered by either the Swift satellite or other GRB missions foreseen in the next decade.Comment: 6 pages, 4 figures. Paper presented at the COSPAR 2004 General Assembly (Paris), accepted for publication in Advances in Space Research in June 2005 and available on-line at the Journal site (http://www.sciencedirect.com/science/journal/02731177), section "Articles in press

    Diginyc partial hydatidiform mole with increased fetal nuchal translucency and ovarian hyperstimulation syndrome.

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    PURPOSE OF INVESTIGATION Hydatidiform mole (HM) is an abnormal pregnancy characterized by proliferation of cytotrophoblast and syncytiotrophoblast and vesicular swelling of placental villi. The fetus or embryo can be absent or abnormal. HMs can be complete or partial. CASE REPORT A case of diginyc partial HM at 12 weeks of gestational age was referred to the present center of prenatal diagnosis. The patient showed ovarian hyperstimulation syndrome. At ultrasonography, increased fetal nuchal translucency (NT) with fetal anomaly was evident, without sonographic signs of placental mole. Pregnancy was terminated with legal abortion. RESULTS Partial HM (PHM) was suspected by ultrasonographic fetal markers with ovarian hyperstimulation syndrome, but the diagnosis was performed only with fluorescent in situ hybridization. In particular fetal NT appeared increased also in diginyc mole. CONCLUSION In order to improve the detection rate of PHM, routine histological examinations may be associated to fluorescent in situ hybridization in all cases of fetal anomalies

    Spectral emissivity and temperature maps of the Solfatara crater from DAIS hyperspectral images

    Get PDF
    Quantitative maps of surface temperature and spectral emissivity have been retrieved on the Solfatara crater at Pozzuoli (Naples) from remote sensing hyperspectral data. The present study relies on thermal infrared images collected on July 27, 1997 by the DAIS hyperspectral sensor owned by the German aerospace center (DLR). The Emissivity Spectrum Normalization method was used to make temperature and emissivity estimates. Raw data were previously transformed in radiance and corrected for the atmospheric contributions using the MODTRAN radiative transfer code and the sensor response functions. During the DAIS flight a radiosonde was launched to collect the atmospheric profiles of pressure, temperature and humidity used as input to the code. Retrieved tem- perature values are in good agreement with temperature measurements performed in situ during the campaign. The spectral emissivity map was used to classify the image in different geo-mineralogical units with the Spec- tral Angle Mapper method. Areas of geologic interest were previously selected using a mask obtained from an NDVI image calculated with two channels of the visible (red) and the near infrared respectively
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