Výsledky vyhľadávania
Názov Predicting Earth-Vas2 parameters of coastal plain sand aquifers using artificial neural Network(s), in the Calabar region of Nigeria Aut.údaje Emmanuel I. Akaerue ... [et al.] Autor Akaerue Emmanuel I. (35%)
Spoluautori Onwuka Obialo S.
George Anthony M.
Ekwok Stephen Eguba
Alarifi Saad S.
Andráš Peter 1953- (30%) UMBFP01 - Katedra geografie a geológie
Eldosouky Ahmed M.
Zdroj.dok. Journal of African Earth Sciences. No. 209 (2024), pp. 1-12. - Oxford : Elsevier Ltd., 2024 Kľúč.slová hydrogeológia - hydrogeology korelačné koeficienty Heslá geogr. Nigéria Jazyk dok. angličtina Krajina Veľká Británia Anotácia This study employs artificial neural networks (ANNs), specifically the Nonlinear Autoregressive with External Input (NARX) model as an ANN add-on for Matlab, to forecast Earth-Vas2 parameters. The model leverages a time series approach, with the Earth-Vas2 index (y(t)) as the predictive target and various parameters (eleva tions, static water level, aquifer material thickness, transmissivity, hydraulic conductivity, specific capacity, vadose media) denoted as x(t) to facilitate accurate predictions. The Levenberg-Marquardt training algorithm was applied to the ANN using geo-hydraulic data from 56 boreholes for training and 24 boreholes for validation and testing. Validation metrics such as mean square error (MSE), correlation coefficient (R), and coefficient of determination (R2 ) were utilized. The results indicate a high degree of accuracy, with low MSE values of 0.0171 (training), 0.0087 (validation), and 0.0327 (testing). Strong correlation coefficients (R) of 0.9882, 0.9898, and 0.9844, along with high R2 values (97.66%), emphasize the robustness of the ANN model. Actual and predicted Earth-Vas2 values exhibit a similar pattern, affirming the model’s effectiveness. The R-value of 0.9882 signifies a strong positive correlation within the model, validating its ability to capture variable interactions in fluid migration control. Geo-hydraulic Earth-Vas2 maps identify areas with varying migration efficiency, guiding groundwater management. The study emphasizes routine subsurface assessments for crucial data in environ mental planning and risk reduction in industrial and municipal activities. This method provides cost-effective estimation of key geo-hydraulic properties for aquifer vulnerability assessments, with far-reaching implica tions for groundwater management, environmental protection, and land use planning. URL Link na plný text Kategória publikačnej činnosti ADC Číslo archívnej kópie 54309 Katal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Báza dát xpca - PUBLIKAČNÁ ČINNOSŤ Odkazy PERIODIKÁ-Súborný záznam periodika 
článok
Názov Direct detection of groundwater accumulation zones in saprock aquifers in tectono-thermal environments Aut.údaje Anthony E. Akpan ... [et al.] Autor Akpan Anthony E. (20%)
Spoluautori Ekwok Stephen Eguba (10%)
Ben Ubong Camilus (5%)
Ebong Ebong Dickson (5%)
Thomas Jewel Emem (5%)
Ekanem Aniekam Martin (5%)
George Nyaknno J. (5%)
Abdelrahman Kamal (5%)
Fnais Mohammed S. (5%)
Eldosouky Ahmed M. (5%)
Andráš Peter 1953- (20%) UMBFP01 - Katedra geografie a geológie
Alarifi Saad S. (10%)
Zdroj.dok. Water. Vol. 15, no 22 (2023), pp. 1-21. - Basel : Multidisciplinary Digital Publishing Institute, 2023 Kľúč.slová podzemné vody podzemné termálne vody saprockové vodonosné vrstvy - saprock aquifers Form.deskr. články - journal articles Jazyk dok. angličtina Krajina Švajčiarsko Anotácia VES data acquired in tectono-thermally disturbed environments sometimes contain outliers when plotted on a bi-logarithmic graph. These noisy datasets usually distort the discernible trend of the VES curve, by plotting abnormally above or below its dominant trend at the point of their occurrence. This type of distortion is different from those arising from other causes such as galvanic and static distortions, which usually affect a segment of a curve without changing the curve’s trend. Allowing these unusual points to remain within the datasets during the data processing and modelling phases always produces unsatisfactory results because their presence usually causes the root-mean-square error to exceed the preset acceptable limit. Consequently, such data points are usually deleted to recover the trend of the curve and generate interpretable models during the traditional curve-smoothening (data processing) phase. This study has shown that these unusual data points are indicative of groundwater accumulation zones in porous medium and can also estimate likely borehole productivities in tectono-thermally disturbed environments. A single-point drop signifies a low-yielding fracture characterized by small apertures. The groundwater yield from this group of fractures can barely support the daily domestic water needs of some families. However, VES curves where two or more points break away from the trend of the curve indicate high-yielding fractures or nonconformities, provided that the resistivity value of the first break-point is lower than those of subsequent ones. The productivity level of this category of fractures is high enough to support the water needs of families. The apparent resistivities of these saturated fractures usually vary between 40 and 500 Wm, depending on the nature of the host rock. These qualitative interpretations have been confirmed by drilling and Water 2023, 15, 3946 17 of 21 pumping test results. Depths to these water-filled fractures, though location-dependent, typically vary between 40 and 100 m in the study area. These saturated fractures are common in locations with high lineament density. Optimal data-quality-management practices—including determining the sensitivity level of the equipment, repeating the measuring process, and changing the potential electrode positions and, where possible, the VES profile orientation—must be implemented to confirm the integrity and subterranean nature of the break-off points. URL Link na plný text Kategória publikačnej činnosti ADC Číslo archívnej kópie 53990 Katal.org. BB301 - Univerzitná knižnica Univerzity Mateja Bela v Banskej Bystrici Báza dát xpca - PUBLIKAČNÁ ČINNOSŤ Odkazy PERIODIKÁ-Súborný záznam periodika článok