Search results for "Servo"
showing 10 items of 283 documents
Analysis of the Effects of Reservoir Operating Scenarios on Downstream Flood Damage Risk Using an Integrated Monte Carlo Modelling Approach
2023
The aim of this study is to analyse the effects of reservoir operating scenarios, for flood damage evaluation downstream of a dam, using a Monte Carlo bivariate modelling chain. The proposed methodology involves a stochastic procedure to calculate flood hydrographs and the evaluation of the consequent flood inundation area by applying a 2D hydraulic model. These results are used to estimate the inundation risk and, as consequence, the relative damage evaluation under different water level conditions in an upstream reservoir. The modelling chain can be summarized as follows: single synthetic stochastic rainfall event generation by using a Monte Carlo procedure through a bivariate copulas ana…
Contour map of the top of the regional geothermal reservoir of Sicily (Italy).
2015
An integrated review of existing geological and geophysical data – partly acquired during oil and gas exploration – combined with new data provided by deep geothermal studies of selected key areas, was used for the 3D modeling and mapping of the top of the geothermal reservoir developed at a regional scale in Sicily (Central Mediterranean). The resulting 1:500,000 scale map covers the area of the whole Sicily (about 25,700 km2) and is devoted to represent the main input for both the thermal modeling and the evaluation of geothermal potential at a regional scale. As the map indicates the distribution at depth of a likely target for geothermal drilling, it can be also used as a rough indicato…
Phytoplankton dynamics in a shallow, hypertrophic reservoir (Lake Arancio, Sicily)
1994
Phytoplankton abundance and composition in the hypertrophic man-made Lake Arancio was analyzed, based on a programme of weekly sampling from May 1990 to November 1991 and supported by measurements of limnological parameters. The highest value of phytoplankton biomass (78 mg l-1) was observed in October 1990, during a bloom of the desmid Closterium limneticum var. fallax, while the lowest (0.15 mg l-1) was measured in April 1991. During spring, autumn and winter 1990, species of the genus Closterium dominated the community, in the sequence: C. aciculare, C. limneticum var. fallax, C. limneticum. The summer community was more diverse with the predominance of organisms belonging to Chlorophyce…
Determination of Changes in the Quality of Surface Water in the River—Reservoir System
2021
Assessing the changing parameters of water quality at different points in the river–reservoir system can help prevent river pollution and implement remedial policies. It is also crucial in modeling water resources. Multivariate statistical analysis is useful for the analysis of changes in surface water quality. It helps to identify indicators that may be responsible for the eutrophication process of a reservoir. Additionally, the analysis of the water quality profile and the water quality index (WQI) is useful in assessing water pollution. These tools can support and verify the results of a multivariate statistical analysis. In this study, changes in water quality parameters of the Turawa r…
Dynamics of hydrofracturing and permeability evolution in layered reservoirs
2015
International audience; A coupled hydro-mechanical model is presented to model fluid driven fracturing in layered porous rocks. In the model the solid elastic continuum is described by a discrete element approach coupled with a fluid continuum grid that is used to solve Darcy based pressure diffusion. The model assumes poro-elasto-plastic effects and yields real time dynamic aspects of the fracturing and effective stress evolution under the influence of excess fluid pressure gradients. We show that the formation and propagation of hydrofractures are sensitive to mechanical and tectonic conditions of the system. In cases where elevated fluid pressure is the sole driving agent in a stable tec…
The dissolution of gypsum of Disueri reservoir left bank
2011
Results of a laboratory research programme on the rate of dissolution of selenitic gypsum are reported and discussed. The tested gypsum samples have been recovered from boreholes drilled in a thick layer outcropping on the left bank of Disueri reservoir located near Gela in Sicily. The tests carried out demonstrate that the rate of dissolution Rd depends essentially upon the velocity v of water flowing over the surface of the gypsum. Values of Rd range from 0.94 to 3 kg/(m2 • day) for v values from 0.05 to 0.20 m/s. Such high rates can account both for the rapid evolution of the existing cavities and for the creation of new caves within the gypsum mass subsequent to the impounding of the re…
Assessment of pahs and selected pesticides in shallow groundwater in the highest protected areas in the Opole region, Poland
2014
The ground water quality was determined after the analyses of water samples from 18 wells. The wells were in the Groundwater Area with the Highest Protection (Triassic water, Opole region, Poland), rural build up. The water table level was low: 0.5 – 18.0 m below the ground surface level (except for one artesian well). The following parameters were determined: pH, EC, colour, ammonium, nitrite, nitrate, dissolved orthophosphate, total phosphorus, dissolved oxygen, BOD, COD-Mn, COD-Cr, humic substances, chloride, sulphate, total hardness, alkalinity, dry residue PAHs (16 compounds), pesticides (6 compounds), however, only selected data were presented in this paper. In all the analysed water …
Eco-epidemiology of tick- and rodent-borne pathogens in boreal forests
2017
Infectious diseases are amongst the ten major causes of human mortality worldwide, 60% of them being animal-borne. Variations of abiotic and biotic conditions are likely to modify the transmission of parasites and pathogens within reservoir species, and, as a consequence, alter the zoonotic risk for human. My thesis aims at elucidating the dynamics and mechanisms of the maintenance of ticks, tick-borne pathogens (TBPs) and the Puumala hantavirus (PUUV) in the reservoir host, the bank vole (Myodes glareolus, BV). In Northern Europe, tick-borne diseases are growing in importance to human because of the latitudinal expansion of the tick Ixodes ricinus. Field monitoring revealed that I. ricinus…
Valutazioni igienico-sanitarie delle acque in tre invasi artificiali della provincia di Palermo destinate al consumo umano
1998
We report the physico-chemical and bacteriological characteristics of three Sicilian reservoirs. The aim of this study was the evaluation of the reservoirs' sanitary conditions, given tha the water is also used for human consumption. 114 samples (4 locations at each lake) were collected in the period from July 1995 to June 1996. We analysed temperature, pH, oxygen saturation, colour and parameters of water mineralization and pollution of natural or human origin.Pathogenic bacteria (Salòmonellae) and opportunistic patjogens such as Pseudomonas aeruginosa and Aeromonas spp. were also investigated. At present, results are not showing particular levels of pollution, and it seems there is no ris…
Application of algae in active biomonitoring of the selected holding reservoirs in swietokrzyskie province
2016
During the years 2014-2015, biomonitoring studies were carried out at three holding reservoirs located in Swietokrzyskie Province (central Poland): Kielce artificial lake, Chancza reservoir and Sielpia reservoir. In sea water algae Palmaria palmata (Linnaeus) Weber & Mohr, exposed in the analysed waters, the increases of concentrations were determined by the atomic absorption spectrometry method (AAS), of the following: Mn, Fe, Cu, Zn, Cd and Pb. Conductivity and pH were also determined in the reservoirs waters. The differences between the increases of heavy metal concentrations in the samples of algae found along the coastline were indicated; they result from different distances from the p…