2021Article de journal ER5 Auteurs : Kassem, Taher; Shahrour, Isam; Khattabi, Jamal El; Raslan, Ahmad Smart and Sustainable Aquaculture Farms Dans: Sustainability, vol. 13, no. 19, 2021, ISSN: 2071-1050, (ACL). Résumé | Liens @article{su131910685,
title = {Smart and Sustainable Aquaculture Farms},
author = {Taher Kassem and Isam Shahrour and Jamal El Khattabi and Ahmad Raslan},
url = {https://www.mdpi.com/2071-1050/13/19/10685},
doi = {10.3390/su131910685},
issn = {2071-1050},
year = {2021},
date = {2021-01-01},
journal = {Sustainability},
volume = {13},
number = {19},
abstract = {This paper presents the design and construction of a smart and sustainable fish farm. The farm is based on the hybrid aquaculture concept that combines the advantages of the recirculation aquaculture system (RAS), the zero-water discharge (ZWD), and smart technology. The system’s smartness consists of using the latest technology, including monitoring and automation, ensuring zero water discharge, good water quality, reduced energy consumption, and high biosecurity. In addition, the system does not use chemicals in the aquaculture process. The paper describes the design of this system, including the hydraulic system, the smart monitoring system, the feeding regime, and the control of the biological parameters. Tests conducted in Tabuk, Saudi Arabia, showed high performance of this system with around 90% survival rate. In addition, observations showed the system’s capacity to maintain the water quality parameters within the optimal water quality ranges, reduce energy consumption, and sustain efficient shrimp waste recycling.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
This paper presents the design and construction of a smart and sustainable fish farm. The farm is based on the hybrid aquaculture concept that combines the advantages of the recirculation aquaculture system (RAS), the zero-water discharge (ZWD), and smart technology. The system’s smartness consists of using the latest technology, including monitoring and automation, ensuring zero water discharge, good water quality, reduced energy consumption, and high biosecurity. In addition, the system does not use chemicals in the aquaculture process. The paper describes the design of this system, including the hydraulic system, the smart monitoring system, the feeding regime, and the control of the biological parameters. Tests conducted in Tabuk, Saudi Arabia, showed high performance of this system with around 90% survival rate. In addition, observations showed the system’s capacity to maintain the water quality parameters within the optimal water quality ranges, reduce energy consumption, and sustain efficient shrimp waste recycling. |
2021Article de journal ER5 Auteurs : Mashhadi, Neda; Shahrour, Isam; Attoue, Nivine; Khattabi, Jamal El; Aljer, Ammar Use of Machine Learning for Leak Detection and Localization in Water Distribution Systems Dans: Smart Cities, vol. 4, no. 4, p. 1293–1315, 2021, ISSN: 2624-6511, (ACL). Résumé | Liens @article{smartcities4040069,
title = {Use of Machine Learning for Leak Detection and Localization in Water Distribution Systems},
author = {Neda Mashhadi and Isam Shahrour and Nivine Attoue and Jamal El Khattabi and Ammar Aljer},
url = {https://www.mdpi.com/2624-6511/4/4/69},
doi = {10.3390/smartcities4040069},
issn = {2624-6511},
year = {2021},
date = {2021-01-01},
journal = {Smart Cities},
volume = {4},
number = {4},
pages = {1293--1315},
abstract = {This paper presents an investigation of the capacity of machine learning methods (ML) to localize leakage in water distribution systems (WDS). This issue is critical because water leakage causes economic losses, damages to the surrounding infrastructures, and soil contamination. Progress in real-time monitoring of WDS and ML has created new opportunities to develop data-based methods for water leak localization. However, the managers of WDS need recommendations for the selection of the appropriate ML methods as well their practical use for leakage localization. This paper contributes to this issue through an investigation of the capacity of ML methods to localize leakage in WDS. The campus of Lille University was used as support for this research. The paper is presented as follows: First, flow and pressure data were determined using EPANET software; then, the generated data were used to investigate the capacity of six ML methods to localize water leakage. Finally, the results of the investigations were used for leakage localization from offline water flow data. The results showed excellent performance for leakage localization by the artificial neural network, logistic regression, and random forest, but there were low performances for the unsupervised methods because of overlapping clusters.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
This paper presents an investigation of the capacity of machine learning methods (ML) to localize leakage in water distribution systems (WDS). This issue is critical because water leakage causes economic losses, damages to the surrounding infrastructures, and soil contamination. Progress in real-time monitoring of WDS and ML has created new opportunities to develop data-based methods for water leak localization. However, the managers of WDS need recommendations for the selection of the appropriate ML methods as well their practical use for leakage localization. This paper contributes to this issue through an investigation of the capacity of ML methods to localize leakage in WDS. The campus of Lille University was used as support for this research. The paper is presented as follows: First, flow and pressure data were determined using EPANET software; then, the generated data were used to investigate the capacity of six ML methods to localize water leakage. Finally, the results of the investigations were used for leakage localization from offline water flow data. The results showed excellent performance for leakage localization by the artificial neural network, logistic regression, and random forest, but there were low performances for the unsupervised methods because of overlapping clusters. |
2021Article de journal ER5 Auteurs : Ghazouli, Khalid El; Khattabi, Jamal El; Shahrour, Isam; Soulhi, Aziz Wastewater flow forecasting model based on the nonlinear autoregressive with exogenous inputs (NARX) neural network Dans: H2Open Journal, vol. 4, no. 1, p. 276-290, 2021. Liens @article{elghazouli:hal-03770701,
title = {Wastewater flow forecasting model based on the nonlinear autoregressive with exogenous inputs (NARX) neural network},
author = {Khalid El Ghazouli and Jamal El Khattabi and Isam Shahrour and Aziz Soulhi},
url = {https://hal.archives-ouvertes.fr/hal-03770701},
doi = {10.2166/h2oj.2021.107},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {H2Open Journal},
volume = {4},
number = {1},
pages = {276-290},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
|
2021Article de journal ER5 Auteurs : Bouaissa, Mohamed; Gharibi, Elkhadir; Ghalit, Mohammad; Taupin, Jean Denis; Khattabi, Jamal El Identifying the origin of groundwater salinization in the Bokoya massif (central Rif, northern Morocco) using hydrogeochemical and isotopic tools Dans: Groundwater for Sustainable Development, vol. 14, p. 100646, 2021, (ACL). Liens @article{bouaissa:hal-03772296,
title = {Identifying the origin of groundwater salinization in the Bokoya massif (central Rif, northern Morocco) using hydrogeochemical and isotopic tools},
author = {Mohamed Bouaissa and Elkhadir Gharibi and Mohammad Ghalit and Jean Denis Taupin and Jamal El Khattabi},
url = {https://hal.archives-ouvertes.fr/hal-03772296},
doi = {10.1016/j.gsd.2021.100646},
year = {2021},
date = {2021-08-01},
urldate = {2021-08-01},
journal = {Groundwater for Sustainable Development},
volume = {14},
pages = {100646},
publisher = {Elsevier},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
|
2021Article de journal ER5 Auteurs : Bouaissa, Mohamed; Ghalit, Mohammad; Taupin, Jean Denis; Khattabi, Jamal El; Gharibi, Elkhadir Assessment of groundwater quality in the Bokoya Massif (Central Rif, Northern Morocco) using several analytical techniques Dans: Euro-Mediterranean Journal for Environmental Integration, vol. 6, no. 1, p. 9, 2021, (ACL). Liens @article{bouaissa:hal-03772353,
title = {Assessment of groundwater quality in the Bokoya Massif (Central Rif, Northern Morocco) using several analytical techniques},
author = {Mohamed Bouaissa and Mohammad Ghalit and Jean Denis Taupin and Jamal El Khattabi and Elkhadir Gharibi},
url = {https://hal.archives-ouvertes.fr/hal-03772353},
doi = {10.1007/s41207-020-00208-5},
year = {2021},
date = {2021-04-01},
urldate = {2021-04-01},
journal = {Euro-Mediterranean Journal for Environmental Integration},
volume = {6},
number = {1},
pages = {9},
publisher = {Springer},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
|
2020Article de journal ER5 Auteurs : Jabari, Samah; Shahrour, Isam; Khattabi, Jamal El Assessment of the Urban Water Security in a Severe Water Stress Area-Application to Palestinian Cities Dans: Water, vol. 12, no. 7, p. 2060, 2020, (ACL). Résumé | Liens @article{,
title = {Assessment of the Urban Water Security in a Severe Water Stress Area-Application to Palestinian Cities},
author = {Samah Jabari and Isam Shahrour and Jamal El Khattabi},
doi = {10.3390/w12072060},
year = {2020},
date = {2020-01-01},
journal = {Water},
volume = {12},
number = {7},
pages = {2060},
abstract = {This paper presents an assessment of the urban water security in a severe water stress area using a semi-quantitative risk-based approach. Water security indicators are selected according to the recommendations of international institutions, the literature review and the opinion of a panel of water experts. Selected indicators cover three fields: water resources, water services and water governance. The field of water resources is described by indicators related to the water resources availability, annual precipitation and the ratio of treated water, while the water services field is described by indicators related to the water service coverage, water losses and the continuity of water supply. Water governance includes three indicators: role and responsibility, access to water information and stakeholder engagement. Water security assessment is conducted in three stages: (i) data collection for five Palestinian cities in the West Bank of Jordan, (ii) determination of the risk score for each indicator using collected data and an expert's opinion, (iii) determination of the global water security score and water security index using the matrix risk assessment and the wise weight assessment ratio analysis (SWARA) methods. Results show that water risk is ranked as extreme for all cities. Risk related to water resources is a major contributor to global risk, followed by water governance.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
This paper presents an assessment of the urban water security in a severe water stress area using a semi-quantitative risk-based approach. Water security indicators are selected according to the recommendations of international institutions, the literature review and the opinion of a panel of water experts. Selected indicators cover three fields: water resources, water services and water governance. The field of water resources is described by indicators related to the water resources availability, annual precipitation and the ratio of treated water, while the water services field is described by indicators related to the water service coverage, water losses and the continuity of water supply. Water governance includes three indicators: role and responsibility, access to water information and stakeholder engagement. Water security assessment is conducted in three stages: (i) data collection for five Palestinian cities in the West Bank of Jordan, (ii) determination of the risk score for each indicator using collected data and an expert's opinion, (iii) determination of the global water security score and water security index using the matrix risk assessment and the wise weight assessment ratio analysis (SWARA) methods. Results show that water risk is ranked as extreme for all cities. Risk related to water resources is a major contributor to global risk, followed by water governance. |
2018Article de journal ER5 Auteurs : Khattabi, Jamal El; Louche, B; Darwishe, H; Chaaban, F; Carlier, E Impact of Fertilizer Application and Agricultural Crops on the Quality of Groundwater in the Alluvial Aquifer, Northern France Dans: Water Air and Soil Pollution, vol. 229, no. 4, p. 128, 2018, (ACL). Résumé | Liens @article{,
title = {Impact of Fertilizer Application and Agricultural Crops on the Quality of Groundwater in the Alluvial Aquifer, Northern France},
author = {Jamal El Khattabi and B Louche and H Darwishe and F Chaaban and E Carlier},
doi = {10.1007/s11270-018-3767-4},
year = {2018},
date = {2018-01-01},
journal = {Water Air and Soil Pollution},
volume = {229},
number = {4},
pages = {128},
abstract = {In France, the quality of water resources with respect to nitrates deteriorated between the beginning of 1970s and 2000s. A stabilization of the situation and of the improvements has been observed punctually since the 2000s. Despite the application of the Nitrates Directive in France (91/676/CEE), the overall situation remains degraded, with numerous increases in nitrate concentrations in the underground waters. In the North of France, an alluvial groundwater's nitrate concentration exceeds the drinking water limit fixed at 50 mg/l, in the sectors of Catillon-sur-Sambre and Rejet-deBeaulieu. In order to quantify and model the impact of agricultural nitrogen on groundwater, an approach based on an integrated model has been established using three specific codes for each lithological horizon: Agriflux (for the root zone), VS2DT (for the unsaturated zone), and ModFlow-MT3D (for the saturated zone). The results illustrate the sensitivity of quality to agricultural crops used. Based on scenarios over 20 years, the predictions show a link between nitrate concentrations in the groundwater and agricultural crops as well as fertilization. Improving quality with a concentration of nitrate less than 50 mg/l requires a reasoned management accompanied by rotations of crops and transformations into grasslands and for sensitive areas the use of the culture producing the least nitrogen flow such as beets. The integrated model constitutes an efficient tool for predicting the evolution of the groundwater quality, especially in sensitive areas like the valleys with a rapid nitrate transfer to the aquifer. The model makes it possible to correctly evaluate the concentrations of nitrates reaching the groundwater with a monitoring of the concentration evolution in each lithological horizon, thus constituting a good tool for the management of agricultural pollution.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
In France, the quality of water resources with respect to nitrates deteriorated between the beginning of 1970s and 2000s. A stabilization of the situation and of the improvements has been observed punctually since the 2000s. Despite the application of the Nitrates Directive in France (91/676/CEE), the overall situation remains degraded, with numerous increases in nitrate concentrations in the underground waters. In the North of France, an alluvial groundwater's nitrate concentration exceeds the drinking water limit fixed at 50 mg/l, in the sectors of Catillon-sur-Sambre and Rejet-deBeaulieu. In order to quantify and model the impact of agricultural nitrogen on groundwater, an approach based on an integrated model has been established using three specific codes for each lithological horizon: Agriflux (for the root zone), VS2DT (for the unsaturated zone), and ModFlow-MT3D (for the saturated zone). The results illustrate the sensitivity of quality to agricultural crops used. Based on scenarios over 20 years, the predictions show a link between nitrate concentrations in the groundwater and agricultural crops as well as fertilization. Improving quality with a concentration of nitrate less than 50 mg/l requires a reasoned management accompanied by rotations of crops and transformations into grasslands and for sensitive areas the use of the culture producing the least nitrogen flow such as beets. The integrated model constitutes an efficient tool for predicting the evolution of the groundwater quality, especially in sensitive areas like the valleys with a rapid nitrate transfer to the aquifer. The model makes it possible to correctly evaluate the concentrations of nitrates reaching the groundwater with a monitoring of the concentration evolution in each lithological horizon, thus constituting a good tool for the management of agricultural pollution. |
2018Article de journal ER5 Auteurs : Khattabi, Jamal El; Carlier, E; Louche, B The Effect of Rock Collapse on Coastal Cliff Retreat along the Chalk Cliffs of Northern France Dans: Journal of Coastal Research, vol. 34, no. 1, p. 136–150, 2018, (ACL). Résumé | Liens @article{,
title = {The Effect of Rock Collapse on Coastal Cliff Retreat along the Chalk Cliffs of Northern France},
author = {Jamal El Khattabi and E Carlier and B Louche},
doi = {10.2112/JCOASTRES-D-16-00116.1},
year = {2018},
date = {2018-01-01},
journal = {Journal of Coastal Research},
volume = {34},
number = {1},
pages = {136--150},
abstract = {Coastal retreat is a topic that concerns all countries located on the coastal edge. This is the case for the chalky cliffs located in the north of France. Here, the cliff base is characterized by chalk rock rich in clay with low mechanical characteristics. To understand the appearance of rock collapses causing cliff retreat, the methodology applied in this report is based on an analytical study and numerical modeling. The model developed with CESAR (i.e. finite element software dedicated to stability) shows deformation affecting gray and blue chalk with separations reaching 3 cm. Simulations carried out with UDEC (i.e. Universal Distinct Element Code) show that constraints are organized around joints when the blocks rearrange themselves, and the effects are mainly seen at the base of the cliff. This study demonstrates the appearance of irregular conjugate fractures within the marly levels of the blue chalk. This type of fracture appears as a result of pressure from the overlying layers and the influence of lateral stress induced by the "Grand Blanc Nez'' formation. These fractures propagate towards the gray chalk and set the limits of different blocks. The displacement of these blocks leads to the obstruction of conduits, which increases the water pressure. The destabilization of the cliff is reflected in the appearance of release cracks, which are strongly influenced by variations in groundwater level. These findings were verified by numerical modeling. This example demonstrates that rock collapses are responsible for coastline retreat in this area. The combination of unpredictable natural phenomena associated with a concentrated spatial area creates a high-risk coastal area retreating at around 0.25 m/y.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
Coastal retreat is a topic that concerns all countries located on the coastal edge. This is the case for the chalky cliffs located in the north of France. Here, the cliff base is characterized by chalk rock rich in clay with low mechanical characteristics. To understand the appearance of rock collapses causing cliff retreat, the methodology applied in this report is based on an analytical study and numerical modeling. The model developed with CESAR (i.e. finite element software dedicated to stability) shows deformation affecting gray and blue chalk with separations reaching 3 cm. Simulations carried out with UDEC (i.e. Universal Distinct Element Code) show that constraints are organized around joints when the blocks rearrange themselves, and the effects are mainly seen at the base of the cliff. This study demonstrates the appearance of irregular conjugate fractures within the marly levels of the blue chalk. This type of fracture appears as a result of pressure from the overlying layers and the influence of lateral stress induced by the "Grand Blanc Nez'' formation. These fractures propagate towards the gray chalk and set the limits of different blocks. The displacement of these blocks leads to the obstruction of conduits, which increases the water pressure. The destabilization of the cliff is reflected in the appearance of release cracks, which are strongly influenced by variations in groundwater level. These findings were verified by numerical modeling. This example demonstrates that rock collapses are responsible for coastline retreat in this area. The combination of unpredictable natural phenomena associated with a concentrated spatial area creates a high-risk coastal area retreating at around 0.25 m/y. |
2017Article de journal ER5 Auteurs : Darwishe, H; Khattabi, Jamal El; Chaaban, F; Louche, B; Masson, E; Carlier, E Prediction and control of nitrate concentrations in groundwater by implementing a model based on GIS and artificial neural networks (ANN) Dans: Environmental Earth Sciences, vol. 76, no. 19, p. 649, 2017, (ACL). Résumé | Liens @article{,
title = {Prediction and control of nitrate concentrations in groundwater by implementing a model based on GIS and artificial neural networks (ANN)},
author = {H Darwishe and Jamal El Khattabi and F Chaaban and B Louche and E Masson and E Carlier},
doi = {10.1007/s12665-017-6990-1},
year = {2017},
date = {2017-01-01},
journal = {Environmental Earth Sciences},
volume = {76},
number = {19},
pages = {649},
abstract = {Groundwater modelling has become a major step for decision support in integrated water resource management, but groundwater models require accurate and spatially distributed data to provide reliable results. Hydrogeological modelling of these data can be implemented with physically based models (i.e. MODFLOW, MT3D.). Other approaches that are simpler to implement may be a good substitute for these numerical approaches. This is the case of probabilistic approaches and especially the statistical approach neural networks. The proposed method (coupling GIS/ANN) is especially suitable for the problem of large-scale and long-term simulation. It has been applied in the spatial prediction of nitrates in the chalk aquifer in Bethune (North of France). This confined chalk aquifer in its northern part provides natural denitrification and ensures a good drinking water quality, while in its southern part this aquifer is facing a high level of nitrate concentrations far above the European Nitrates Directive standard. A good groundwater management of this ecosystems service is therefore of great importance for regional water management. Thus, the spatial distribution of nitrate concentration obtained by GIS/ANN coupling model was compared with the results obtained from the numerical modelling (MT3D) and validated by the real measurements. ANN modelling seems to be more realistic than MT3D modelling both for 2003 and 2004. This is true for both of the nitrate concentrations and their difference. So, ANN modelling's spatially distributed difference with observed data ranges from - 3.67 to + 1.24 mg/l in 2003 and - 10.8 to + 6.51 mg/l in 2004, whereas for the MT3D model, this difference ranges from - 11.5 to + 17.9 mg/l in 2003 and - 9.91 to + 16.9 mg/l in 2004. The satisfactory results of the ANN model allowed to launch prospective simulations for 2025 under two groundwater recharge scenarios: a deficit year (150 mm/year) and a rainy year (500 mm/year) show an expansion of the exploitable zone ([NO3-] < 50 mg/L) in the case of a rainy year. The results demonstrate the potential of ANN modelling of spatially distributed hydrogeological data for groundwater management of nitrate pollution. From a groundwater management point of view, the GIS/ANN modelling represents an alternative data analysis to obtain fast results using a less tedious method whose results are satisfactory.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
Groundwater modelling has become a major step for decision support in integrated water resource management, but groundwater models require accurate and spatially distributed data to provide reliable results. Hydrogeological modelling of these data can be implemented with physically based models (i.e. MODFLOW, MT3D.). Other approaches that are simpler to implement may be a good substitute for these numerical approaches. This is the case of probabilistic approaches and especially the statistical approach neural networks. The proposed method (coupling GIS/ANN) is especially suitable for the problem of large-scale and long-term simulation. It has been applied in the spatial prediction of nitrates in the chalk aquifer in Bethune (North of France). This confined chalk aquifer in its northern part provides natural denitrification and ensures a good drinking water quality, while in its southern part this aquifer is facing a high level of nitrate concentrations far above the European Nitrates Directive standard. A good groundwater management of this ecosystems service is therefore of great importance for regional water management. Thus, the spatial distribution of nitrate concentration obtained by GIS/ANN coupling model was compared with the results obtained from the numerical modelling (MT3D) and validated by the real measurements. ANN modelling seems to be more realistic than MT3D modelling both for 2003 and 2004. This is true for both of the nitrate concentrations and their difference. So, ANN modelling's spatially distributed difference with observed data ranges from - 3.67 to + 1.24 mg/l in 2003 and - 10.8 to + 6.51 mg/l in 2004, whereas for the MT3D model, this difference ranges from - 11.5 to + 17.9 mg/l in 2003 and - 9.91 to + 16.9 mg/l in 2004. The satisfactory results of the ANN model allowed to launch prospective simulations for 2025 under two groundwater recharge scenarios: a deficit year (150 mm/year) and a rainy year (500 mm/year) show an expansion of the exploitable zone ([NO3-] < 50 mg/L) in the case of a rainy year. The results demonstrate the potential of ANN modelling of spatially distributed hydrogeological data for groundwater management of nitrate pollution. From a groundwater management point of view, the GIS/ANN modelling represents an alternative data analysis to obtain fast results using a less tedious method whose results are satisfactory. |
2016Article de journal ER4 Auteurs : Carlier, Erick; Khattabi, Jamal El Impact of global warming on Intensity-Duration-Frequency (IDF) relationship of precipitation: A case study of Toronto, Canada Dans: Open Journal of Modern Hydrology, vol. 6, p. 1-7, 2016, (ACLO). Résumé @article{Carlier2016,
title = {Impact of global warming on Intensity-Duration-Frequency (IDF) relationship of precipitation: A case study of Toronto, Canada},
author = {Erick Carlier and Jamal El Khattabi},
year = {2016},
date = {2016-01-01},
journal = {Open Journal of Modern Hydrology},
volume = {6},
pages = {1-7},
abstract = {Annual maximum rainfall intensity for several duration and return periods has been analyzed according to the gumbel distribution. the intensity-duration-frequency (idf) curves before and after 1980 have been computed and compared. for the city of toronto, it is shown that the rainfall intensities after 1980 are lower than those from before this date. this is especially clear for those of short duration. comparing our results with those of other authors, it appears that, for the moment, no general law on the impact of global warming on the curves intensity duration frequency cannot be made. it appears that the impact of global warming on rainfall varies with geographic location and that it is not possible to draw some general conclusions across the planet.},
note = {ACLO},
keywords = {ER4},
pubstate = {published},
tppubtype = {article}
}
Annual maximum rainfall intensity for several duration and return periods has been analyzed according to the gumbel distribution. the intensity-duration-frequency (idf) curves before and after 1980 have been computed and compared. for the city of toronto, it is shown that the rainfall intensities after 1980 are lower than those from before this date. this is especially clear for those of short duration. comparing our results with those of other authors, it appears that, for the moment, no general law on the impact of global warming on the curves intensity duration frequency cannot be made. it appears that the impact of global warming on rainfall varies with geographic location and that it is not possible to draw some general conclusions across the planet. |
2015Article de journal ER4 Auteurs : Carlier, Erick; Khattabi, Jamal El A probabilistic approach for spring recession flows analysis Dans: Open Journal of Modern Hydrology, vol. 5, p. 11-18, 2015, (ACLO). Résumé @article{Carlier2015,
title = {A probabilistic approach for spring recession flows analysis},
author = {Erick Carlier and Jamal El Khattabi},
year = {2015},
date = {2015-01-01},
journal = {Open Journal of Modern Hydrology},
volume = {5},
pages = {11-18},
abstract = {Spring recession flows are analyzed from a Bayesian point of view.
Two general equations are derived and it is shown that the classical
formulas of recession flow are particular cases of both equations.
It is shown that most of the recession equations reflect a non-Markovian
process. That means that the groundwater storage exhibits a memory
effect and that there is a nonlinear relationship between flow and
storage. The Bayesian approach presented in this paper makes it possible
to give a probabilistic meaning to recession flow equations derived
according to a physical approach and can be an alternative to the
study of complex reservoir for which the physical processes governing
recession flow are unclear. Twelve spring recession flow series are
analysed in order to validate the probabilistic approach presented
in this paper and a conceptual model of storage- outflow is proposed.},
note = {ACLO},
keywords = {ER4},
pubstate = {published},
tppubtype = {article}
}
Spring recession flows are analyzed from a Bayesian point of view.
Two general equations are derived and it is shown that the classical
formulas of recession flow are particular cases of both equations.
It is shown that most of the recession equations reflect a non-Markovian
process. That means that the groundwater storage exhibits a memory
effect and that there is a nonlinear relationship between flow and
storage. The Bayesian approach presented in this paper makes it possible
to give a probabilistic meaning to recession flow equations derived
according to a physical approach and can be an alternative to the
study of complex reservoir for which the physical processes governing
recession flow are unclear. Twelve spring recession flow series are
analysed in order to validate the probabilistic approach presented
in this paper and a conceptual model of storage- outflow is proposed. |
2013Article de journal ER4 Auteurs : Alayat, Hacène; Khattabi, Jamal El; Lamouroux, Christian Evolution spatiale des caractéristiques physico-chimiques des eaux du lac Oubeira imposé par les conditions sévères de la secheresse (extreme NE algerien) Dans: European Scientific Journal, vol. 9, no. 36, p. 564-579, 2013, (ACLN). Résumé @article{Alayat2013,
title = {Evolution spatiale des caractéristiques physico-chimiques des eaux du lac Oubeira imposé par les conditions sévères de la secheresse (extreme NE algerien)},
author = {Hacène Alayat and Jamal El Khattabi and Christian Lamouroux},
year = {2013},
date = {2013-01-01},
journal = {European Scientific Journal},
volume = {9},
number = {36},
pages = {564-579},
abstract = {The endoreic lake oubeira, vast lake located in algeria (36°51' n- 8°23' e), at an altitude of 23 m, is subject to severe natural and anthropic constraints during the dry season, which generally begins in april and is completed in october. due to its geometrical configuration and wind exposure, the water of the lake is well brewed within the entire water column. the first results, covering all the shallow water level, show the average mineralisation of hot moderate water, which releases co2 in the atmosphere, an alkaline ph, higher than 8, related to intense evaporation and biological activity, in particular photosynthesis and calcite precipitation. physicochemical measurements brought a considerable contribution to identify the individualization of two distinct water masses, one in the east and the other in the west, and the absence of limnologic layers. the conditions of the environment make organic particles degraded in the water column. conservation of organic remains in the reducing environment, represented by the mud, is much reduced. almost circular, the lake oubeira has a flat bottom, generally covered with greyish mud, because of the presence of reduced iron, less than 2 m thick. the thickness of the water blade hardly exceeds 1.50 m and the maximum depth, between the surface of the lake and the substratum is about 3.50 m, in period of dryness},
note = {ACLN},
keywords = {ER4},
pubstate = {published},
tppubtype = {article}
}
The endoreic lake oubeira, vast lake located in algeria (36°51' n- 8°23' e), at an altitude of 23 m, is subject to severe natural and anthropic constraints during the dry season, which generally begins in april and is completed in october. due to its geometrical configuration and wind exposure, the water of the lake is well brewed within the entire water column. the first results, covering all the shallow water level, show the average mineralisation of hot moderate water, which releases co2 in the atmosphere, an alkaline ph, higher than 8, related to intense evaporation and biological activity, in particular photosynthesis and calcite precipitation. physicochemical measurements brought a considerable contribution to identify the individualization of two distinct water masses, one in the east and the other in the west, and the absence of limnologic layers. the conditions of the environment make organic particles degraded in the water column. conservation of organic remains in the reducing environment, represented by the mud, is much reduced. almost circular, the lake oubeira has a flat bottom, generally covered with greyish mud, because of the presence of reduced iron, less than 2 m thick. the thickness of the water blade hardly exceeds 1.50 m and the maximum depth, between the surface of the lake and the substratum is about 3.50 m, in period of dryness |
2012Article de journal ER5 Auteurs : Chaaban, F; Darwishe, H; Battiau-Queney, Y; Louche, B; Masson, E; Khattabi, Jamal El; Carlier, E Using ArcGIS (R) Modelbuilder and Aerial Photographs to Measure Coastline Retreat and Advance: North of France Dans: Journal of Coastal Research, vol. 28, no. 6, p. 1567–1579, 2012, (ACL). Résumé | Liens @article{,
title = {Using ArcGIS (R) Modelbuilder and Aerial Photographs to Measure Coastline Retreat and Advance: North of France},
author = {F Chaaban and H Darwishe and Y Battiau-Queney and B Louche and E Masson and Jamal El Khattabi and E Carlier},
doi = {10.2112/JCOASTRES-D-11-00054.1},
year = {2012},
date = {2012-11-01},
journal = {Journal of Coastal Research},
volume = {28},
number = {6},
pages = {1567--1579},
abstract = {Chaaban, F.; Darwishe, H.; Battiau-Queney, Y.; Louche, B.; Masson, E.; El Khattabi, J., and earlier, E., 2012. Using ArcGIS (R) Modelbuilder and aerial photographs to measure coastline retreat and advance: North of France. Journal of Coastal Research, 28(6), 1567-1579. Coconut Creek (Florida), ISSN 0749-0208. Coastal areas are naturally dynamic with changes occurring over periods of time. When the shoreline moves landward, coastal erosion becomes a serious problem, and the rate of change has to be calculated. Coastline retreat is one of the best indicators of coastal erosion. Here, the geographic information systems (GIS) platform (ArcGIS (R) 9.3.1; Esri software) is used to study the long-term (last 59 years) shoreline change in the area of Hardelot-Plage and Sainte Cecile-Plage (a north-south 14-km-long beach), in northern France. The primary aim of this study was to develop a methodology for calculating shoreline change using ArcGIS Modelbuilder and aerial photographs. Changes in 14 coastlines over the course of 59 years (from 1946 to 2005) were digitized and represented in ArcGIS 9.3.1 platform. Two hundred and ninety-two transects perpendicular to the shoreline were used to estimate coastal erosion and deduce the recession rate. The Modelbuilders (two models) created and used in this work are generic models that can be used for geoprocessing linear features. One model can be used to ascertain the intersection between linear features (transects and shorelines), adding a new field to the attribute table and calculating the geometry of the intersection points. A second model can housed to add a new field to the attribute table and calculate the distance on the transect lines between the linear reference feature and other linear features, in this study between the baseline (established adjacent to the series of shoreline positions) and the shoreline. The results show that the shoreline change rates between 1947 and 2005 along the Hardelot and Sainte Cecile coasts are generally negative; 82.2% of transects have values less than zero (i.e., retreat) and outside of the error margin (+/- 10 m). Nevertheless the shoreline change shows successive phases of advance and retreat over the same period.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
Chaaban, F.; Darwishe, H.; Battiau-Queney, Y.; Louche, B.; Masson, E.; El Khattabi, J., and earlier, E., 2012. Using ArcGIS (R) Modelbuilder and aerial photographs to measure coastline retreat and advance: North of France. Journal of Coastal Research, 28(6), 1567-1579. Coconut Creek (Florida), ISSN 0749-0208. Coastal areas are naturally dynamic with changes occurring over periods of time. When the shoreline moves landward, coastal erosion becomes a serious problem, and the rate of change has to be calculated. Coastline retreat is one of the best indicators of coastal erosion. Here, the geographic information systems (GIS) platform (ArcGIS (R) 9.3.1; Esri software) is used to study the long-term (last 59 years) shoreline change in the area of Hardelot-Plage and Sainte Cecile-Plage (a north-south 14-km-long beach), in northern France. The primary aim of this study was to develop a methodology for calculating shoreline change using ArcGIS Modelbuilder and aerial photographs. Changes in 14 coastlines over the course of 59 years (from 1946 to 2005) were digitized and represented in ArcGIS 9.3.1 platform. Two hundred and ninety-two transects perpendicular to the shoreline were used to estimate coastal erosion and deduce the recession rate. The Modelbuilders (two models) created and used in this work are generic models that can be used for geoprocessing linear features. One model can be used to ascertain the intersection between linear features (transects and shorelines), adding a new field to the attribute table and calculating the geometry of the intersection points. A second model can housed to add a new field to the attribute table and calculate the distance on the transect lines between the linear reference feature and other linear features, in this study between the baseline (established adjacent to the series of shoreline positions) and the shoreline. The results show that the shoreline change rates between 1947 and 2005 along the Hardelot and Sainte Cecile coasts are generally negative; 82.2% of transects have values less than zero (i.e., retreat) and outside of the error margin (+/- 10 m). Nevertheless the shoreline change shows successive phases of advance and retreat over the same period. |
2012Article de journal ER5 Auteurs : Chaaban, F; Darwishe, H; Louche, B; Battiau-Queney, Y; Masson, E; Khattabi, Jamal El; Carlier, E Geographical information system approach for environmental management in coastal area (Hardelot-Plage, France) Dans: Environmental Earth Sciences, vol. 65, no. 1, p. 183–193, 2012, (ACL). Résumé | Liens @article{,
title = {Geographical information system approach for environmental management in coastal area (Hardelot-Plage, France)},
author = {F Chaaban and H Darwishe and B Louche and Y Battiau-Queney and E Masson and Jamal El Khattabi and E Carlier},
doi = {10.1007/s12665-011-1080-2},
year = {2012},
date = {2012-01-01},
journal = {Environmental Earth Sciences},
volume = {65},
number = {1},
pages = {183--193},
abstract = {The use of geographic information system (GIS) minimizes the effort and improves the efficiency of numerical models. The GIS provides a platform for high capacity collection, management, manipulation, analysis, modeling and display of spatial data. The conceptual model is created using GIS objects including points, arcs and polygons so that it can accurately represent real world condition. According to the research problem, the geographical model is based on Hypergraph Based Data Structure method, and a conceptual data model has been created from which a physical data model was elaborated in ArcGIS9.3 platform. The groundwater modeling system (GMS) provides a powerful tool for hydrodynamics modeling and it is able to solve complex problems such as the groundwater flow and seawater intrusion. The sand-dune system of Hardelot-Plage (North of France) suffers from a lack of well-developed foredune. This problem is linked to the almost constant saturation of beach sand which is the potential source of dune nourishment. In the south of Hardelot, the coastline is slowly, but constantly retreating. To remedy this situation, a coupling between a GIS and GMS was adopted, in order to find the possible scenarios which could lower the piezometric surface in the concerned area and allow dune nourishment again. The GMS used supports the Modflow-2000 code. A direct approach to designing Modflow finite difference model is tedious and less intuitive, specifically for complex boundary and initial conditions. Therefore, a Modflow model can be developed either using a grid or conceptual model approach. The preparation of input data modeling is tedious and takes a long time. The model created in GMS was calibrated against the historical and observed water level data for 1995-2006. Then a hydrodispersive model (MT3d code in GMS) was launched for evaluating sea-water intrusion. The model was run to generate groundwater and salt concentration scenario during pumping tests.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
The use of geographic information system (GIS) minimizes the effort and improves the efficiency of numerical models. The GIS provides a platform for high capacity collection, management, manipulation, analysis, modeling and display of spatial data. The conceptual model is created using GIS objects including points, arcs and polygons so that it can accurately represent real world condition. According to the research problem, the geographical model is based on Hypergraph Based Data Structure method, and a conceptual data model has been created from which a physical data model was elaborated in ArcGIS9.3 platform. The groundwater modeling system (GMS) provides a powerful tool for hydrodynamics modeling and it is able to solve complex problems such as the groundwater flow and seawater intrusion. The sand-dune system of Hardelot-Plage (North of France) suffers from a lack of well-developed foredune. This problem is linked to the almost constant saturation of beach sand which is the potential source of dune nourishment. In the south of Hardelot, the coastline is slowly, but constantly retreating. To remedy this situation, a coupling between a GIS and GMS was adopted, in order to find the possible scenarios which could lower the piezometric surface in the concerned area and allow dune nourishment again. The GMS used supports the Modflow-2000 code. A direct approach to designing Modflow finite difference model is tedious and less intuitive, specifically for complex boundary and initial conditions. Therefore, a Modflow model can be developed either using a grid or conceptual model approach. The preparation of input data modeling is tedious and takes a long time. The model created in GMS was calibrated against the historical and observed water level data for 1995-2006. Then a hydrodispersive model (MT3d code in GMS) was launched for evaluating sea-water intrusion. The model was run to generate groundwater and salt concentration scenario during pumping tests. |
2009Article de journal ER5 Auteurs : Serhal, H; Bernard, D; Khattabi, Jamal El; Sabine, B L; Shahrour, Isam Impact of fertilizer application and urban wastes on the quality of groundwater in the Cambrai Chalk aquifer, Northern France Dans: Environmental Geology, vol. 57, no. 7, p. 1579–1592, 2009, (ACL). Résumé | Liens @article{,
title = {Impact of fertilizer application and urban wastes on the quality of groundwater in the Cambrai Chalk aquifer, Northern France},
author = {H Serhal and D Bernard and Jamal El Khattabi and B L Sabine and Isam Shahrour},
doi = {10.1007/s00254-008-1433-7},
year = {2009},
date = {2009-01-01},
journal = {Environmental Geology},
volume = {57},
number = {7},
pages = {1579--1592},
abstract = {Since 1975, Europe sets up its policy to limit the degradation and the pollution of the aquatic environments through 30 directives and regulations. In the north of France, the nitrate concentrations measured in the groundwater exceed the water drinking limit fixed at 50 mg/L by the European framework directive in the field of water (2000/60/EC). This high concentration is due to intensive agriculture, industrialization and demographic growth. Several programs were launched in order to resolve this situation: "Ferti-better" or the use of fertilizer in moderation and installation and amelioration of wastewater collect and treatment systems. In order to estimate the influence of the anthropic activities on the quality of groundwater in the "Artois-Picardy" basin, a preliminary validation on parcel and district scale were necessary. The impact of these programs in the "Cambrai district" was evaluated using an integrated approach, which is based on the use of four numerical models: AgriFlux, VS2DT, Modflow and MT3D. The results illustrate an improvement due to the "Ferti-Better" program initiated in 1990 and punctual degradation under urbanized areas. Predictions (2015) show a spatial evolution of nitrates concentration varying with the thickness of unsaturated layer. The integrated model constitutes an efficient tool for predicting the evolution of the groundwater quality. This approach is important to control the application of the new European laws in the water field.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
Since 1975, Europe sets up its policy to limit the degradation and the pollution of the aquatic environments through 30 directives and regulations. In the north of France, the nitrate concentrations measured in the groundwater exceed the water drinking limit fixed at 50 mg/L by the European framework directive in the field of water (2000/60/EC). This high concentration is due to intensive agriculture, industrialization and demographic growth. Several programs were launched in order to resolve this situation: "Ferti-better" or the use of fertilizer in moderation and installation and amelioration of wastewater collect and treatment systems. In order to estimate the influence of the anthropic activities on the quality of groundwater in the "Artois-Picardy" basin, a preliminary validation on parcel and district scale were necessary. The impact of these programs in the "Cambrai district" was evaluated using an integrated approach, which is based on the use of four numerical models: AgriFlux, VS2DT, Modflow and MT3D. The results illustrate an improvement due to the "Ferti-Better" program initiated in 1990 and punctual degradation under urbanized areas. Predictions (2015) show a spatial evolution of nitrates concentration varying with the thickness of unsaturated layer. The integrated model constitutes an efficient tool for predicting the evolution of the groundwater quality. This approach is important to control the application of the new European laws in the water field. |
2008Article de journal ER5 Auteurs : Bernard, D; Khattabi, Jamal El; Lefevre, E; Serhal, H; Bastin-Lacherez, S; Shahrour, Isam Origin of nickel in water solution of the chalk aquifer in the north of France and influence of geochemical factors Dans: Environmental Geology, vol. 53, no. 5, p. 1129–1138, 2008, (ACL). Résumé | Liens @article{,
title = {Origin of nickel in water solution of the chalk aquifer in the north of France and influence of geochemical factors},
author = {D Bernard and Jamal El Khattabi and E Lefevre and H Serhal and S Bastin-Lacherez and Isam Shahrour},
doi = {10.1007/s00254-007-0704-z},
year = {2008},
date = {2008-01-01},
journal = {Environmental Geology},
volume = {53},
number = {5},
pages = {1129--1138},
abstract = {In the north of France, high registers of nickel are sometimes recorded within the chalk aquifer. In a confined context, the presence of pyrite in the covering clays or in the marcasite nodules encrusted in the clay may constitute a natural source of trace metals. With an objective of sanitary control, the limits of chemical contents regulating the quality of water destined for human consumption have been lowered by the European Framework Directive in the field of water policy (2000/60/EC). As a result, nickel limits have been reduced from 50 to 20 mu g/l. The analyses, carried out on three water catchment fields in our area of study, were centred on variable parameters (Eh, O-2(d), pH, Conductivity, T), major elements (SO4, NO3) and metals (Fe, Ni, Mn, Co). The acquired data enabled us to identify from one hand, the conditions which are presented within the site, special thanks to the evolution of nitrate and iron contents and on the other hand, the natural origin (geological) of nickel for two of the three sites studied based essentially on the evaluation of the Nickel/Cobalt ratio. Thus, on the first site, the evolution of nickel content and nitrate content showed the influence of the phenomenon of denitrification on the re-mobilisation of the nickel. Whereas on the second site, a high variation of total iron content and oxygen dissolved in solution highlighted a particular phenomenon of oxidation of the pyrite through molecular oxygen. Finally, the correlation with the sulphates clearly showed behaviour of the nickel, once released, that was entirely dependent on the phenomenon of adsorption on the iron and manganese hydroxides.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
In the north of France, high registers of nickel are sometimes recorded within the chalk aquifer. In a confined context, the presence of pyrite in the covering clays or in the marcasite nodules encrusted in the clay may constitute a natural source of trace metals. With an objective of sanitary control, the limits of chemical contents regulating the quality of water destined for human consumption have been lowered by the European Framework Directive in the field of water policy (2000/60/EC). As a result, nickel limits have been reduced from 50 to 20 mu g/l. The analyses, carried out on three water catchment fields in our area of study, were centred on variable parameters (Eh, O-2(d), pH, Conductivity, T), major elements (SO4, NO3) and metals (Fe, Ni, Mn, Co). The acquired data enabled us to identify from one hand, the conditions which are presented within the site, special thanks to the evolution of nitrate and iron contents and on the other hand, the natural origin (geological) of nickel for two of the three sites studied based essentially on the evaluation of the Nickel/Cobalt ratio. Thus, on the first site, the evolution of nickel content and nitrate content showed the influence of the phenomenon of denitrification on the re-mobilisation of the nickel. Whereas on the second site, a high variation of total iron content and oxygen dissolved in solution highlighted a particular phenomenon of oxidation of the pyrite through molecular oxygen. Finally, the correlation with the sulphates clearly showed behaviour of the nickel, once released, that was entirely dependent on the phenomenon of adsorption on the iron and manganese hydroxides. |
2006Article de journal ER5 Auteurs : Carlier, E; Khattabi, Jamal El; Potdevin, J L Solute transport in sand and chalk: a probabilistic approach Dans: Hydrological Processes, vol. 20, no. 5, p. 1047–1055, 2006, (ACL). Résumé | Liens @article{,
title = {Solute transport in sand and chalk: a probabilistic approach},
author = {E Carlier and Jamal El Khattabi and J L Potdevin},
doi = {10.1002/hyp.5931},
year = {2006},
date = {2006-01-01},
journal = {Hydrological Processes},
volume = {20},
number = {5},
pages = {1047--1055},
abstract = {A probabilistic approach is used to simulate particle tracking for two types of porous medium. The first is sand grains with a single intergranular porosity. Particle tracking is carried out by advection and dispersion. The second is chalk granulates with intergranular and matrix porosities. Sorption can occur with advection and dispersion during particle tracking. Particle tracking is modelled as the sum of elementary steps with independent random variables in the sand medium. An exponential distribution is obtained for each elementary step and shows that the whole process is Markovian. A Gamma distribution or probability density function is then deduced. The relationships between dispersivity and the elementary step are given using the central limit theorem. Particle tracking in the chalky medium is a non-Markovian process. The probability density function depends on a power of the distance. Experimental simulations by dye tracer tests on a column have been performed for different distances and discharges. The probabilistic approach computations are in good agreement with the experimental data. The probabilistic computation seems an interesting and complementary approach to simulate transfer phenomena in porous media with respect to the traditional numerical methods. Copyright (c) 2006 John Wiley & Sons, Ltd.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
A probabilistic approach is used to simulate particle tracking for two types of porous medium. The first is sand grains with a single intergranular porosity. Particle tracking is carried out by advection and dispersion. The second is chalk granulates with intergranular and matrix porosities. Sorption can occur with advection and dispersion during particle tracking. Particle tracking is modelled as the sum of elementary steps with independent random variables in the sand medium. An exponential distribution is obtained for each elementary step and shows that the whole process is Markovian. A Gamma distribution or probability density function is then deduced. The relationships between dispersivity and the elementary step are given using the central limit theorem. Particle tracking in the chalky medium is a non-Markovian process. The probability density function depends on a power of the distance. Experimental simulations by dye tracer tests on a column have been performed for different distances and discharges. The probabilistic approach computations are in good agreement with the experimental data. The probabilistic computation seems an interesting and complementary approach to simulate transfer phenomena in porous media with respect to the traditional numerical methods. Copyright (c) 2006 John Wiley & Sons, Ltd. |
2005Article de journal ER5 Auteurs : Carlier, E; Khattabi, Jamal El Proposal for a probabilistic model of dispersion: A first validation Dans: Mathematical and Computer Modelling, vol. 42, no. 9-10, p. 1137–1144, 2005, (ACL). Résumé | Liens @article{,
title = {Proposal for a probabilistic model of dispersion: A first validation},
author = {E Carlier and Jamal El Khattabi},
doi = {10.1016/j.mcm.2004.05.014},
year = {2005},
date = {2005-01-01},
journal = {Mathematical and Computer Modelling},
volume = {42},
number = {9-10},
pages = {1137--1144},
abstract = {The probabilistic approach is used to simulate the particle tracking for two types of porous media. The first one is sand grains with a single intergranular porosity. The particle tracking is carried out by advection and dispersion. The second one is chalk granulates with intergranular and matrix porosities. Sorption can occur with advection and dispersion during particle tracking. The particle tracking is simulated as the sum of elementary steps with independent random variables in the sand medium. An exponential distribution is obtained for each elementary step and shows that the whole process is Markovian. A gamma distribution or probability density function is then deduced. The relationship between dispersivity and the elementary step is given using the central limit theorem. The particle tracking in the chalky medium is a non-Markovian process. The probability density function depends of a power to the distance. Experimental simulation by dye tracer tests on a column have been performed for different distances and discharges. The probabilistic approach computations are in good agreement with the experimental data. The probabilistic computation seems an interesting and complementary approach to simulate transfer phenomena in porous media with respect to the traditional numerical methods. (c) 2005 Elsevier Ltd. All rights reserved.},
note = {ACL},
keywords = {ER5},
pubstate = {published},
tppubtype = {article}
}
The probabilistic approach is used to simulate the particle tracking for two types of porous media. The first one is sand grains with a single intergranular porosity. The particle tracking is carried out by advection and dispersion. The second one is chalk granulates with intergranular and matrix porosities. Sorption can occur with advection and dispersion during particle tracking. The particle tracking is simulated as the sum of elementary steps with independent random variables in the sand medium. An exponential distribution is obtained for each elementary step and shows that the whole process is Markovian. A gamma distribution or probability density function is then deduced. The relationship between dispersivity and the elementary step is given using the central limit theorem. The particle tracking in the chalky medium is a non-Markovian process. The probability density function depends of a power to the distance. Experimental simulation by dye tracer tests on a column have been performed for different distances and discharges. The probabilistic approach computations are in good agreement with the experimental data. The probabilistic computation seems an interesting and complementary approach to simulate transfer phenomena in porous media with respect to the traditional numerical methods. (c) 2005 Elsevier Ltd. All rights reserved. |
