The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Luca Ciabatta - One of the best experts on this subject based on the ideXlab platform.
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estimating the Drainage Rate from surface soil moisture drydowns application of dfd model to in situ soil moisture data
Journal of Hydrology, 2018Co-Authors: Ehsan Jalilvand, M Tajrishy, Luca Brocca, Christian Massari, Sedighehalsadat Ghazi Zadeh Hashemi, Luca CiabattaAbstract:Abstract The large heterogeneity in soil surface conditions makes it impracticable to obtain reliable estimates of soil hydraulic parameters for areas larger than few squared kilometers. However, identifying these parameters on a global scale is essential for many hydrological and climatic applications. In this study, a new approach named Drainage from Drydown (DfD) is proposed to estimate the coefficients of Drainage using soil moisture observations. DfD firstly selects multiple drydown events when surface runoff and evapotranspiration Rates are negligible compared to the Drainage Rate. Secondly, by inverting the soil water balance equation, the Drainage coefficients are obtained. Synthetic experiments are carried out in order to tune the overall procedure. DfD is then tested with in situ observations at 8 different sites worldwide characterized by different climates and soil types. The reliability of the DfD is evaluated by using the DfD Drainage coefficients in a physically based soil water balance model (SWB) for simulating soil moisture and a rainfall estimation model (SM2RAIN). The results indicate that the climate and the soil conditions exert an important role in the occurrence and magnitude of Drainage Rate. DfD is found capable of correctly identify periods in which Drainage Rate is the dominant process. Drainage coefficients obtained from DfD are consistent with the expected soil hydraulic properties based on the soil texture and land cover at each site. By using DfD Drainage coefficients to estimate rainfall and soil moisture via SM2RAIN and SWB, promising results are obtained with median correlation of 0.83 and 0.91 between estimated and in situ data. However, in sites characterized by high Rate of evapotranspiration (>700 mm/year) and low permeable soil (e.g., clay) the DfD performance is reduced. Overall, DfD demonstRates the ability to decouple Drainage and evapotranspiration processes and to estimate the Drainage coefficients from in situ observations.
Ehsan Jalilvand - One of the best experts on this subject based on the ideXlab platform.
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estimating the Drainage Rate from surface soil moisture drydowns application of dfd model to in situ soil moisture data
Journal of Hydrology, 2018Co-Authors: Ehsan Jalilvand, M Tajrishy, Luca Brocca, Christian Massari, Sedighehalsadat Ghazi Zadeh Hashemi, Luca CiabattaAbstract:Abstract The large heterogeneity in soil surface conditions makes it impracticable to obtain reliable estimates of soil hydraulic parameters for areas larger than few squared kilometers. However, identifying these parameters on a global scale is essential for many hydrological and climatic applications. In this study, a new approach named Drainage from Drydown (DfD) is proposed to estimate the coefficients of Drainage using soil moisture observations. DfD firstly selects multiple drydown events when surface runoff and evapotranspiration Rates are negligible compared to the Drainage Rate. Secondly, by inverting the soil water balance equation, the Drainage coefficients are obtained. Synthetic experiments are carried out in order to tune the overall procedure. DfD is then tested with in situ observations at 8 different sites worldwide characterized by different climates and soil types. The reliability of the DfD is evaluated by using the DfD Drainage coefficients in a physically based soil water balance model (SWB) for simulating soil moisture and a rainfall estimation model (SM2RAIN). The results indicate that the climate and the soil conditions exert an important role in the occurrence and magnitude of Drainage Rate. DfD is found capable of correctly identify periods in which Drainage Rate is the dominant process. Drainage coefficients obtained from DfD are consistent with the expected soil hydraulic properties based on the soil texture and land cover at each site. By using DfD Drainage coefficients to estimate rainfall and soil moisture via SM2RAIN and SWB, promising results are obtained with median correlation of 0.83 and 0.91 between estimated and in situ data. However, in sites characterized by high Rate of evapotranspiration (>700 mm/year) and low permeable soil (e.g., clay) the DfD performance is reduced. Overall, DfD demonstRates the ability to decouple Drainage and evapotranspiration processes and to estimate the Drainage coefficients from in situ observations.
He Li - One of the best experts on this subject based on the ideXlab platform.
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drilling large diameter cross measure boreholes to improve gas Drainage in highly gassy soft coal seams
Journal of Natural Gas Science and Engineering, 2015Co-Authors: Wei Yang, Ziwen Li, Yuan Pang, He LiAbstract:Abstract Reducing gas content via cross-measure boreholes is one of the primary gas control technologies in China, where most outburst-threat coal seams are soft and highly gassy. Regardless of the significant costs associated with drilling boreholes, the gas Drainage Rate remains low because of the low permeability of the soft coal seam and the small influence zone of a single borehole. In this paper, the effect of increasing borehole diameter on coal seam permeability is discussed and a new method for drilling large diameter cross-measure boreholes by using the water-jet technique is proposed. Numerical modeling results indicate that the plastic zone and the effective influence zone of one borehole expand as borehole diameter increases, and the interaction between adjacent boreholes is strengthened. The field test shows that when the borehole diameter is 1.0 m, the effective influence zone radius reaches 4 m which is 2.67 times larger than that of an ordinary borehole. After using the new method, the number of cross-measure boreholes per hundred meters and the length of cross-measure boreholes per meter can reduce by 32.5% and 42.9%, respectively. In addition, the gas Drainage Rate reaches 52.1%, and the monthly excavation length of coal roadway increases from 50–70 m to 109 m.
Garth H Utter - One of the best experts on this subject based on the ideXlab platform.
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the Rate of pleural fluid Drainage as a criterion for the timing of chest tube removal theoretical and practical considerations
The Annals of Thoracic Surgery, 2013Co-Authors: Garth H UtterAbstract:Clinicians place chest tubes approximately 1 million times each year in the United States, but little information is available to guide their management. Specifically, use of the Rate of pleural fluid Drainage as a criterion for tube removal is not standardized. Absent such tubes, pleural fluid drains primarily through parietal pleural lymphatics at Rates approaching 500 mL of fluid per day or more for each hemithorax. Early removal of tubes does not appear to be harmful. A noninferiority randomized trial currently in progress comparing removal without considering the Drainage Rate to a conservative threshold (2 mL/kg body weight in 24 hours) may better inform tube management.
Sedighehalsadat Ghazi Zadeh Hashemi - One of the best experts on this subject based on the ideXlab platform.
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estimating the Drainage Rate from surface soil moisture drydowns application of dfd model to in situ soil moisture data
Journal of Hydrology, 2018Co-Authors: Ehsan Jalilvand, M Tajrishy, Luca Brocca, Christian Massari, Sedighehalsadat Ghazi Zadeh Hashemi, Luca CiabattaAbstract:Abstract The large heterogeneity in soil surface conditions makes it impracticable to obtain reliable estimates of soil hydraulic parameters for areas larger than few squared kilometers. However, identifying these parameters on a global scale is essential for many hydrological and climatic applications. In this study, a new approach named Drainage from Drydown (DfD) is proposed to estimate the coefficients of Drainage using soil moisture observations. DfD firstly selects multiple drydown events when surface runoff and evapotranspiration Rates are negligible compared to the Drainage Rate. Secondly, by inverting the soil water balance equation, the Drainage coefficients are obtained. Synthetic experiments are carried out in order to tune the overall procedure. DfD is then tested with in situ observations at 8 different sites worldwide characterized by different climates and soil types. The reliability of the DfD is evaluated by using the DfD Drainage coefficients in a physically based soil water balance model (SWB) for simulating soil moisture and a rainfall estimation model (SM2RAIN). The results indicate that the climate and the soil conditions exert an important role in the occurrence and magnitude of Drainage Rate. DfD is found capable of correctly identify periods in which Drainage Rate is the dominant process. Drainage coefficients obtained from DfD are consistent with the expected soil hydraulic properties based on the soil texture and land cover at each site. By using DfD Drainage coefficients to estimate rainfall and soil moisture via SM2RAIN and SWB, promising results are obtained with median correlation of 0.83 and 0.91 between estimated and in situ data. However, in sites characterized by high Rate of evapotranspiration (>700 mm/year) and low permeable soil (e.g., clay) the DfD performance is reduced. Overall, DfD demonstRates the ability to decouple Drainage and evapotranspiration processes and to estimate the Drainage coefficients from in situ observations.
