29,933 research outputs found

    Evaluating several satellite precipitation estimates and global ground-based dataset on Sicily (Italy)

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    The developing of satellite-based precipitation retrieval systems, presents great potentialities for several applications ranging from weather and meteorological applications to hydrological modelling. Evaluating performances for these estimates is essential in order to understand their real capabilities and suitability related to each application. In this study an evaluation analysis of satellite precipitation retrieval systems has been carried out for the area of Sicily (Italy). Sicily is an island in the Mediterranean sea with a particular climatology and morphology, which is considered as an interesting test site for satellite precipitation products on the European mid-latitude area. A high density rain-gauges network has been used to evaluate selected satellite precipitation products. Sicily has an area of 26,000 km2 and the gauge density of the network considered in this study is about 250 km2/gauge. Four satellite products (CMORPH, PERSIANN, TMPA-RT, PERSIANN-CCS) along with two adjusted products (TMPA and PERSIANN Adjusted) have been selected for the evaluation. Evaluation and comparisons among selected products is performed with reference to the data provided by the gauge network of Sicily and using statistical and visualization tools. Results show that bias is relevant for all satellite products and climatic considerations are reported to address this issue. Moreover bias errors are observed for the adjusted products even though they are reduced respect to only-satellite products. In order to analyze this result, the ground-based precipitation dataset used by adjusted products (GPCC dataset), has been examined and weaknesses arising from spatial sampling of precipitation process have been identified for the study area. Therefore possible issues deriving from using global ground-based datasets for local scales are pointed out from this application. © 2012 SPIE

    Evaluation and comparison of satellite precipitation estimates with reference to a local area in the Mediterranean Sea

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    Precipitation is one of the major variables for many applications and disciplines related to water resources and the geophysical Earth system. Satellite retrieval systems, rain-gauge networks, and radar systems are complementary to each other in terms of their coverage and capability of monitoring precipitation. Satellite-rainfall estimate systems produce data with global coverage that can provide information in areas for which data from other sources are unavailable. Without referring to ground measurements, satellite-based estimates can be biased and, although some gauge-adjusted satellite-precipitation products have been already developed, an effective way of integrating multi-sources of precipitation information is still a challenge.In this study, a specific area, the Sicilia Island (Italy), has been selected for the evaluation of satellite-precipitation products based on rain-gauge data. This island is located in the Mediterranean Sea, with a particular climatology and morphology, which can be considered an interesting test site for satellite-precipitation products in the European mid-latitude area. Four satellite products (CMORPH, PERSIANN, PERSIANN-CCS, and TMPA-RT) and two GPCP-adjusted products (TMPA and PERSIANN Adjusted) have been selected. Evaluation and comparison of selected products is performed with reference to data provided by the rain-gauge network of the Island Sicilia and by using statistical and graphical tools. Particular attention is paid to bias issues shown both by only-satellite and adjusted products. In order to investigate the current and potential possibilities of improving estimates by means of adjustment procedures using GPCC ground precipitation, the data have been retrieved separately and compared directly with the reference rain-gauge network data set of the study area.Results show that bias is still considerable for all satellite products, then some considerations about larger area climatology, PMW-retrieval algorithms, and GPCC data are discussed to address this issue, along with the spatial and seasonal characterization of results. © 2013 Elsevier B.V

    TRACER STUDY TERHADAP PESERTA PELATIHAN KEWIRAUSAHAAN YANG DISELENGGARAKAN OLEH PUSAT PENGEMBANGAN KEWIRAUSAHAAN LPPM UNIVERSITAS SEBELAS MARET TAHUN 2000-2007

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    Tracer Study adalah kegiatan penelusuran alumni khususnya dalam hal pencarian kerja, situasi kerja, dan pemanfaatan pemerolehan kompetensi selama kuliah di universitas. Tracer study bermanfaat untuk berbagai pihak, yakni perguruan tinggi dan terutama untuk alumni guna memberikan informasi penting mengenai hubungan antara dunia pendidikan tinggi dengan dunia kerja. Tracer study dapat menyajikan informasi mendalam dan rinci mengenai relevansi antara dunia kerja dengan lulusan perguruan tinggi. Dalam rangka melakukan perbaikan berkelanjutan Pusat Pengembangan Kewirausahaan LPPM UNS merasa perlu untuk mengetahui bagaimana dampak dari berbagai pelatihan terhadap “lulusannya”. Untuk itulah kegiatan tracer study ini dilakukan. Kegiatan ini pada dasarnya untuk melakukan pengembangan program kerja dalam rangka peningkatan mutu berkelanjutan. Informasi mengenai kompetensi yang relevan bagi dunia kerja dapat membantu upaya perbaikan kurikulum dan sistem pembelajaran. Di sisi lain, dunia industri dan dunia kerja dapat "mereferensi" ke dalam instistusi pendidikan tinggi melalui tracer study ini, dan dengan demikian dapat menyiapkan diri dengan menyediakan pelatihanpelatihan yang lebih relevan bagi sarjana pencari kerja baru. Kata kunci : tracer study, pendidikan, dunia kerja

    Numerical simulation of solid tumor blood perfusion and drug delivery during the “vascular normalization window” with antiangiogenic therapy

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    This Article is provided by the Brunel Open Access Publishing Fund - Copyright @ 2011 Hindawi PublishingTo investigate the influence of vascular normalization on solid tumor blood perfusion and drug delivery, we used the generated blood vessel network for simulations. Considering the hemodynamic parameters changing after antiangiogenic therapies, the results show that the interstitial fluid pressure (IFP) in tumor tissue domain decreases while the pressure gradient increases during the normalization window. The decreased IFP results in more efficient delivery of conventional drugs to the targeted cancer cells. The outcome of therapies will improve if the antiangiogenic therapies and conventional therapies are carefully scheduled
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