scholarly journals From Lithological Modelling to Groundwater Modelling: A Case Study in the Tiber River Alluvial Valley

Geosciences ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 507
Author(s):  
Cristina Di Salvo ◽  
Marco Mancini ◽  
Massimiliano Moscatelli ◽  
Maurizio Simionato ◽  
Gian Paolo Cavinato ◽  
...  
Keyword(s):  
Hydrological Model ◽  
Three Dimensional ◽  
National Research Council ◽  
Regional Government ◽  
Three Dimensional Model ◽  
Hydrogeological Model ◽  
Alluvial Deposits ◽  
Tiber River

This study presents the results of a research project financed by the Lazio Regional Government. The research focused on defining an integrated model of recent alluvial deposits in the Tiber River. To achieve this objective, geological boreholes were made to monitor the aquifer and in situ and laboratory tests were carried out. The data obtained were used to detail stratigraphic aspects and improve the comprehension of water circulation beneath the recent alluvial deposits of the Tiber River in the urban area of Rome, between the Ponte Milvio bridge and the Tiber Island. The stratigraphic intervals recognised in the boreholes were parameterised based on their litho-technical characteristics. The new data acquired, and integrated with existing data in the database of Institute of Environmental Geology and Geoengineering of the Italian National Research Council, made it possible to produce a three-dimensional model of the lithologies in the study area. The model of the subsoil, simplified for applied reasons, was described in hydrostratigraphic terms: three different lithotypes were subjected to piezometric levels monitoring. Finally, the research generated a numerical hydrological model in a steady state. In general, this study demonstrates how a numerical hydrogeological model calibrated by piezometric monitoring data can support the construction of a geological model, discarding or confirming certain hypotheses and suggesting other means of reconstructing sedimentary bodies.

scholarly journals From Lithological Modelling to Groundwater Modelling: A Case Study in the Tiber River Alluvial Valley

2021 ◽  
Author(s):  
Cristina Di Salvo ◽  
Marco Mancini ◽  
Massimiliano Moscatelli ◽  
Maurizio Simionato ◽  
Gian Paolo Cavinato ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Stationary Regime ◽  
Regional Government ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Hydrogeological Model ◽  
Alluvial Deposits ◽  
Tiber River

This study presents the results of a research project financed by the Lazio Regional Government. The research focused on defining an integrated model of recent alluvial deposits in the Tiber River. To achieve this objective, geological boreholes were made to monitor the aquifer and in situ and laboratory tests carried out. The data obtained was used to detail stratigraphic aspects and improve the comprehension of water circulation beneath the recent alluvial deposits of the Tiber River in the urban area of Rome, between the Ponte Milvio bridge and the Tiber Island. The stratigraphic intervals recognised in the boreholes were parameterised based on their litho-technical characteristics. The new data acquired, and integrated with existing data in the CNR IGAG database, made it possible to produce a three-dimensional model of the lithologies in the study area.The model of the subsoil, simplified for applied reasons, was described in hy-drostratigraphic terms: three different lithotypes were subjected to piezometric levels monitor-ing. Finally, the research generated a numerical hydrological level in a stationary regime. In general, this study demonstrates how a numerical hydrogeological model calibrated by piezo-metric monitoring data can support the construction of a geological model, discarding or con-firming certain hypotheses and suggesting other means of reconstructing sedimentary bodies.

scholarly journals Data assimilation for volcanic ash plumes using a satellite observational operator: a case study on the 2010 Eyjafjallajökull volcanic eruption

2017 ◽  
Vol 17 (2) ◽  
pp. 1187-1205 ◽  
Author(s):  
Guangliang Fu ◽  
Fred Prata ◽  
Hai Xiang Lin ◽  
Arnold Heemink ◽  
Arjo Segers ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Volcanic Ash ◽  
Three Dimensional ◽  
Forecast Accuracy ◽  
Improve Model ◽  
Powerful Approach ◽  
Using Data ◽  
D Model

Abstract. Using data assimilation (DA) to improve model forecast accuracy is a powerful approach that requires available observations. Infrared satellite measurements of volcanic ash mass loadings are often used as input observations for the assimilation scheme. However, because these primary satellite-retrieved data are often two-dimensional (2-D) and the ash plume is usually vertically located in a narrow band, directly assimilating the 2-D ash mass loadings in a three-dimensional (3-D) volcanic ash model (with an integral observational operator) can usually introduce large artificial/spurious vertical correlations.In this study, we look at an approach to avoid the artificial vertical correlations by not involving the integral operator. By integrating available data of ash mass loadings and cloud top heights, as well as data-based assumptions on thickness, we propose a satellite observational operator (SOO) that translates satellite-retrieved 2-D volcanic ash mass loadings to 3-D concentrations. The 3-D SOO makes the analysis step of assimilation comparable in the 3-D model space.Ensemble-based DA is used to assimilate the extracted measurements of ash concentrations. The results show that satellite DA with SOO can improve the estimate of volcanic ash state and the forecast. Comparison with both satellite-retrieved data and aircraft in situ measurements shows that the effective duration of the improved volcanic ash forecasts for the distal part of the Eyjafjallajökull volcano is about 6 h.

scholarly journals Ballast bed resistance characteristics based on discrete-element modeling

2018 ◽  
Vol 10 (6) ◽  
pp. 168781401878146 ◽  
Author(s):  
Zhiping Zeng ◽  
Shanyi Song ◽  
Weidong Wang ◽  
Haijian Yan ◽  
Guoshu Wang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Discrete Element ◽  
Discrete Element Modeling ◽  
Slope Gradient ◽  
Three Dimensional Model ◽  
Lateral Resistance ◽  
In Situ Experiments ◽  
Distribution Limits ◽  
Longitudinal Resistance

In this study, in situ experiments were conducted to study the changing characteristics of the lateral and longitudinal resistance of a ballast bed, and a three-dimensional model for the ballast bed and sleeper was constructed based on the discrete-element method. The effects of the lateral and longitudinal resistance of the ballast bed, such as gravel ballast grading, sleeper depth, the angle of the shoulder slope, and ballast bed shoulder width, among others, were studied. The results suggest that (1) the lateral and longitudinal resistance of the ballast bed increases with the widening of ballast grading, and within the size distribution limits, the resistance of the ballast bed satisfies the specification; (2) the lateral and longitudinal resistance of ballast bed increases with an increase in the sleeper depth and the resistance of ballast bed satisfies the specifications for sleeper depth greater than 150 mm; (3) the lateral resistance of the ballast bed increases with a decrease in the angle of the shoulder slope, whereas the longitudinal resistance remains unchanged and the resistance of the ballast bed satisfies the specifications for slope gradient of 1:1.75 or less; and finally, (4) the lateral resistance of the ballast bed increases with the widening of the ballast bed shoulder, whereas the longitudinal resistance remains unchanged, and the resistance of ballast bed satisfies the specifications when the shoulder width is greater than 400 mm.

scholarly journals A virtual diorama. Mapping archives in situ at places of cultural significance

1970 ◽  
pp. 22-36
Author(s):  
Jonathan Westin ◽  
Gunnar Almevik
Keyword(s):  
Spatial Information ◽  
Three Dimensional ◽  
Physical Space ◽  
Cultural Significance ◽  
Dimensional Reconstruction ◽  
Historical Photographs ◽  
New Applications ◽  
Archive Material

Using the wooden church of Södra Råda as a case study, this article concerns new applications of technology to contextualise and activate archive material in situ at places of cultural significance. Using a combination of augmented reality and virtual reality, we describe a process of turning historical photographs and two-dimensional reconstruction drawings into three-dimensional virtual models that can be lined up to a physical space. The leading questions for our investigation concern how archive material can be contextualised, and how the result may be made accessible in situ and contribute to place development. The result of this research suggests possibilities for using historical photographs to faithfully reconstruct lost historical spaces as three-dimensional surfaces that contextualise documentation and offer spatial information.

scholarly journals Hydraulic modeling of combined sewers overflow integrating the results of the SWMM and CFX models.

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
D. Pulgarín ◽  
J. Plaza ◽  
J. Ruge ◽  
J. Rojas
Keyword(s):  
Three Dimensional ◽  
Hydraulic Modeling ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
One Dimensional ◽  
Ansys Cfx ◽  
Combined Sewer ◽  
The One ◽  
Swmm Model

This study proposes a methodology for the calibration of combined sewer overflow (CSO), incorporating the results of the three-dimensional ANSYS CFX model in the SWMM one-dimensional model. The procedure consists of constructing calibration curves in ANSYS CFX that relate the input flow to the CSO with the overflow, to then incorporate them into the SWMM model. The results obtained show that the behavior of the flow over the crest of the overflow weir varies in space and time. Therefore, the flow of entry to the CSO and the flow of excesses maintain a non-linear relationship, contrary to the results obtained in the one-dimensional model. However, the uncertainty associated with the idealization of flow methodologies in one dimension is reduced under the SWMM model with kinematic wave conditions and simulating CSO from curves obtained in ANSYS CFX. The result obtained facilitates the calibration of combined sewer networks for permanent or non-permanent flow conditions, by means of the construction of curves in a three-dimensional model, especially when the information collected in situ is limited.

scholarly journals Three-dimensional model of bone marrow

Blood ◽  
1978 ◽  
Vol 51 (4) ◽  
pp. 633-643 ◽  
Author(s):  
N Mohandas ◽  
M Prenant
Keyword(s):  
Bone Marrow ◽  
Close Association ◽  
Three Dimensional ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Scale Models ◽  
Marrow Space ◽  
Normal Rat

Abstract Three-dimensional scale models of bone marrow from a hypertransfused and a normal rat were constructed. The model of marrow from the hypertransfused rat demonstrated the existence of distinct erythroblastic islands in situ in which the erythroblasts underwent sychronous maturation. Macrophages were found in close association with the developing erythroblasts. The immature erythroblasts were tightly grouped, but as they matured they began to move apart. Erythroblasts in individual clusters were found to be at the same stage of morphologic maturation. In contrast, the model of marrow from the normal rat showed a majority of clusters containing erythroblasts at various stages of maturation. Erythropoiesis was not spatially restricted to the area proximal to the sinuses but was found to occur over the entire marrow space. Thrombopoiesis, however, was found to take place exclusively in the immediate vicinity of the marrow sinuses.

scholarly journals Analysis of Cyclist’s Drag on the Aero Position Using Numerical Simulations and Analytical Procedures: A Case Study

2020 ◽  
Vol 17 (10) ◽  
pp. 3430 ◽  
Author(s):  
Pedro Forte ◽  
Daniel A. Marinho ◽  
Pantelis T. Nikolaidis ◽  
Beat Knechtle ◽  
Tiago M. Barbosa ◽  
...  
Keyword(s):  
Linear Regression ◽  
Numerical Simulations ◽  
Three Dimensional ◽  
Three Dimensional Model ◽  
Paired Samples ◽  
Computational Fluid Dynamics Cfd ◽  
Analytical Procedures ◽  
Previous Training ◽  
Very High

Background: Resistance acting on a cyclist is a major concern among the cycling fraternity. Most of the testing methods require previous training or expensive equipment and time-consuming set-ups. By contrast, analytical procedures are more affordable and numerical simulations are perfect for manipulating and controlling inputs. The aim of this case study was to compare the drag of a cyclist in the aero position as measured using numerical simulation and analytical procedures. Methods: An elite male cyclist (65 kg in mass and 1.72 m in height) volunteered to take part in this research. The cyclist was wearing his competition gear, helmet and bicycle. A three-dimensional model of the bicycle and cyclist in the aero position was obtained to run the numerical simulations. Computational fluid dynamics (CFD) and a set of analytical procedures were carried out to assess drag, frontal area and drag coefficient, between 1 m/s and 22 m/s, with increments of 1 m/s. The t-test paired samples and linear regression were selected to compare, correlate and assess the methods agreement. Results: No significant differences (t = 2.826; p = 0.275) between CFD and analytical procedures were found. The linear regression showed a very high adjustment for drag (R2 = 0.995; p < 0.001). However, the drag values obtained by the analytical procedures seemed to be overestimated, even though without effect (d = 0.11). Conclusions: These findings suggest that drag might be assessed using both a set of analytical procedures and CFD.

scholarly journals Disassembly Sequence Planning (DSP) Applied to a Gear Box: Comparison between Two Literature Studies

2020 ◽  
Vol 10 (13) ◽  
pp. 4591 ◽  
Author(s):  
Leonardo Frizziero ◽  
Alfredo Liverani
Keyword(s):  
Three Dimensional ◽  
Evaluation Criteria ◽  
Three Dimensional Model ◽  
Specific Component ◽  
Disassembly Sequence Planning ◽  
Sequence Planning ◽  
New Methods ◽  
Disassembly Sequence ◽  
Mechanical Products

This work aims to analyze the characteristics and importance that design techniques for disassembly assume in the modern design phase of a mechanism. To this end, the study begins by considering a three-dimensional model of a gear motor, taken from the components of which the overall drawings are arranged and from the relief of those not available. Once the mechanism has been digitally reconstructed, the activity focuses on the study of the optimal disassembly sequence by comparing different methodologies, according to two evaluation criteria—minimizing the time taken and minimizing the number of tool changes necessary to complete the sequence. The main results of the work are (1) defining a standard methodology to improve disassembly sequence planning, (2) finding the best disassembly sequence for the specific component among the literature and eventually new methods, and (3) offering to the industrial world a way to optimize maintenance operations in mechanical products. Referring to the limitation of the present works, it can be affirmed that the results are limited to the literature explored and to the case study examined.

scholarly journals Calibration of a Three-dimensional slope stability evaluation in Brazilian iron open pit mine

2021 ◽  
Author(s):  
Vidal Félix Navarro Torres ◽  
Rodrigo Dockendorff ◽  
Juan Manuel Girao Sotomayor ◽  
Cristian Castro ◽  
Aristotelina Ferreira da Silva
Keyword(s):  
Three Dimensional ◽  
Structural Features ◽  
Open Pit ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Strength Parameters ◽  
Dimensional Section ◽  
The Stability ◽  
Evaluation Techniques

Abstract It has historically been frequent among geotechnical practitioners, that the stability analysis of the slopes of an open pit is performed using a two dimensional section representing the highest and steepest walls within a certain geological setting. However, the literature shows that to predict rupture events in an open pit, a three-dimensional analysis would better represent the actual conditions, as the spatial distribution of the lithology and the structural features play an important role when defining the stability of the slopes. This paper presents the case study of an open it located in Brazil, which experienced instabilities between the years 2001-2019. An evaluation of the behavior of the open pit was performed by calibrating the strength parameters to represent the best documented rupture events. The three-dimensional model was made using the FLAC3D software. The results show that there is a good correlation between the results of the model and the reports of past instabilities. Finally, recommendations are presented for the inter-ramp angles for each lithology based on the calibrated stability analyzes performed. This work seeks to contribute to the knowledge in evaluation techniques for the three-dimensional behavior of open pits.

scholarly journals Improved the in-Situ Remediation Effect of Sediment Microbial Fuel Cells by Optimizing the Anode Structure

2021 ◽  
Author(s):  
Henan Li ◽  
Guohong Liu ◽  
Chao Li ◽  
Yongli Sun ◽  
Yujie Feng
Keyword(s):  
Microbial Fuel Cells ◽  
River Sediment ◽  
Three Dimensional ◽  
Honeycomb Structure ◽  
Pollutant Removal ◽  
In Situ Remediation ◽  
Higher Power ◽  
Sediment Carbon

Abstract Six 60-L benthic microbial electrochemical systems (BMES) were built for the bioremediation of river sediment. Carbon mesh anodes with honeycomb-structure supports were compared with horizontal anodes, and the system was tested using different cover depths and anode densities. The pollutant removal, electricity generation, and electrochemistry of the six BMES with different anodes was examined using the Ashi River (Harbin, China) as a case study. Total organic carbon (TOC) and total nitrogen (TN) removal from sediments in BMES with three-dimensional anodes were 20%~30% and 20%~33% higher for the other reactors. Moreover, the honeycomb-structure of the anode also resulted in higher power density and improved humus removal.

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