Quantitative classification of carbonate aquifers based on hydrodynamic behaviour

AbstractA quantitative classification of carbonate aquifers based on hydrodynamic behaviour is introduced. This type of classification is necessary to understand the physical functioning of carbonate hydrogeological systems and to provide a realistic interpretation of field data. Carbonate aquifers are generally considered as karst systems; however, geomorphology and aquifer geology alone are insufficient for determining hydrodynamic behaviour. Analysis of spring and well hydrographs based on analytical solutions is applied to establishing a quantitative classification. A base-flow recession coefficient is used as an indicator of hydrodynamic behaviour. Detailed numerical analyses suggest that carbonate systems can be classified into two distinct groups based on hydrodynamic behaviour. The physical processes depend on a combination of hydraulic and geometric parameters, and their functional relationships can be quantitatively determined. The proposed classification methodology involves making an assumption about aquifer type, estimating aquifer properties from hydrograph data, and comparing the results with field observations. The proposed classification methodology was applied to aquifers representing the two groups of carbonate systems. In both cases, the applied methods revealed crucial information about hydrodynamic functioning of the investigated systems. While the studied limestone aquifer showed karstic hydrodynamic behaviour, the investigation of a dolomite aquifer disproves a priori assumptions on karstic flow conditions. Dolomite aquifers represent an ambiguous group of carbonates and require caution in the selection of investigation tools and interpretation of hydrogeological data. The introduced methodology provides a reliable means of determining the hydrodynamic functioning of an aquifer and supports the quantitative classification of carbonate hydrogeological systems.

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Specificity of Aircraft Crash Compared to Other Missile Impacts

Volume 4: Structural Integrity; Next Generation Systems; Safety and Security; Low Level Waste Management and Decommissioning; Near Term Deployment: Plant Designs, Licensing, Construction, Workforce and Public Acceptance ◽

10.1115/icone16-48946 ◽

2008 ◽

Author(s):

Pierre Kœchlin ◽

Serguei¨ Potapov

Keyword(s):

A Priori ◽

Structural Response ◽

Bending Moment ◽

Experimental Tests ◽

Research Field ◽

Quantitative Classification ◽

Stress Resultant ◽

Physical Phenomena ◽

Aircraft Crash

Before modeling an aircraft crash on a shield building, it is very important to understand the physical phenomena and the structural behavior associated with this kind of impact. In the scientific literature, aircraft crash is classified as a soft impact, or as an impact of deformable missile. Nevertheless the existing classifications are not precise enough to be able to predict the structural response mode. In this paper, the author proposes a quantitative classification of soft and hard impacts, based on structural considerations, and in accordance with existing definitions and moreover with intuition. The experimental tests carried out during the last thirty years in the research field of aircraft crash are reviewed in the light of the new classification. It shows that this characterization has a real physical meaning: it gives the limit between two kinds of failure. Furthermore, since it is on one hand an a priori classification and on the other hand expressed in terms of non-dimension variables, it is very helpful to calibrate new experimental tests for aircraft crash. Finally, using this classification, the paper explains that during an aircraft crash, the perforation process of a concrete shield building is the result of structural waves (bending and shear waves). It opens the way to a prediction of aircraft crash perforation based on a criterion expressed in terms of stress resultant variables (combined bending moment, shear force and membrane force).

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Machine learning algorithm improved automated droplet classification of ddPCR for detection of BRAF V600E in paraffin-embedded samples

Scientific Reports ◽

10.1038/s41598-021-92014-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gabriel A. Colozza-Gama ◽

Fabiano Callegari ◽

Nikola Bešič ◽

Ana C. de J. Paviza ◽

Janete M. Cerutti

Keyword(s):

Machine Learning ◽

Sanger Sequencing ◽

Learning Algorithm ◽

Absolute Quantification ◽

Braf V600e Mutation ◽

Braf V600e ◽

Driver Genes ◽

Quantitative Classification ◽

Cancer Driver

AbstractSomatic mutations in cancer driver genes can help diagnosis, prognosis and treatment decisions. Formalin-fixed paraffin-embedded (FFPE) specimen is the main source of DNA for somatic mutation detection. To overcome constraints of DNA isolated from FFPE, we compared pyrosequencing and ddPCR analysis for absolute quantification of BRAF V600E mutation in the DNA extracted from FFPE specimens and compared the results to the qualitative detection information obtained by Sanger Sequencing. Sanger sequencing was able to detect BRAF V600E mutation only when it was present in more than 15% total alleles. Although the sensitivity of ddPCR is higher than that observed for Sanger, it was less consistent than pyrosequencing, likely due to droplet classification bias of FFPE-derived DNA. To address the droplet allocation bias in ddPCR analysis, we have compared different algorithms for automated droplet classification and next correlated these findings with those obtained from pyrosequencing. By examining the addition of non-classifiable droplets (rain) in ddPCR, it was possible to obtain better qualitative classification of droplets and better quantitative classification compared to no rain droplets, when considering pyrosequencing results. Notable, only the Machine learning k-NN algorithm was able to automatically classify the samples, surpassing manual classification based on no-template controls, which shows promise in clinical practice.

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Quantitative classification of autocatalytic strength for material decomposition based on the ratio of heat release

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-020-10418-2 ◽

2021 ◽

Author(s):

Wen-qian Wu ◽

Ze Dong ◽

Bei-bei Xue ◽

Zi-chao Guo ◽

Li-ping Chen ◽

...

Keyword(s):

Heat Release ◽

Material Decomposition ◽

Quantitative Classification

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Relationships of Hydrological Seasons in Rivers and Groundwaters in Selected Catchments in Poland

Water ◽

10.3390/w13030250 ◽

2021 ◽

Vol 13 (3) ◽

pp. 250

Author(s):

Przemysław Tomalski ◽

Edmund Tomaszewski ◽

Dariusz Wrzesiński ◽

Leszek Sobkowiak

Keyword(s):

River Flow ◽

Geographical Location ◽

Base Flow ◽

Water Shortages ◽

Groundwater Levels ◽

Average Value ◽

Geographical Regions ◽

New Variables ◽

Mixed Types

The study applied the method of hydrological season identification in a time series of river total and base flows and in groundwater levels. The analysis covered a series of daily measurements from the period 2008–2017 in nine catchments located in different geographical regions of Poland. The basis of the classification of hydrological seasons, previously applied for river discharges only, was the transformation of the original variables into a series reflecting three statistical features estimated for single-name days of a year from a multiyear: average value, variation coefficient, and autocorrelation coefficient. New variables were standardized and after hierarchical clustering, every day of a year had a defined type, valorizing three features which refer to quantity, variability, and the stochastic nature of total and base river flow as well as groundwater stage. Finally, sequences of days were grouped into basic (homogenous) seasons of different types and transitional seasons including mixed types of days. Analysis indicated determinants of types, length, and frequency of identified hydrological seasons especially related to river regime, hydrogeological and hydrometeorological conditions as well as physiographical background were directly influenced by geographical location. Analysis of the co-occurrence of the same types of hydrological seasons allowed, in some catchments, periods of synchronic alimentation (groundwater and base flow, mainly in the cold half-year) and water shortages (all three components, mainly in the warm half-year) to be identified.

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Towards a hydrological classification of European soils: preliminary test of its predictive power for the base flow index using river discharge data

Hydrology and Earth System Sciences ◽

10.5194/hess-11-1501-2007 ◽

2007 ◽

Vol 11 (4) ◽

pp. 1501-1513 ◽

Cited By ~ 31

Author(s):

M. K. Schneider ◽

F. Brunner ◽

J. M. Hollis ◽

C. Stamm

Keyword(s):

Water Movement ◽

Base Flow ◽

Regression Coefficients ◽

Northern Europe ◽

Flow Index ◽

Discharge Data ◽

Base Flow Index ◽

The Uk

Abstract. Predicting discharge in ungauged catchments or contaminant movement through soil requires knowledge of the distribution and spatial heterogeneity of hydrological soil properties. Because hydrological soil information is not available at a European scale, we reclassified the Soil Geographical Database of Europe (SGDBE) at 1:1 million in a hydrological manner by adopting the Hydrology Of Soil Types (HOST) system developed in the UK. The HOST classification describes dominant pathways of water movement through soil and was related to the base flow index (BFI) of a catchment (the long-term proportion of base flow on total stream flow). In the original UK study, a linear regression of the coverage of HOST classes in a catchment explained 79% of BFI variability. We found that a hydrological soil classification can be built based on the information present in the SGDBE. The reclassified SGDBE and the regression coefficients from the original UK study were used to predict BFIs for 103 catchments spread throughout Europe. The predicted BFI explained around 65% of the variability in measured BFI in catchments in Northern Europe, but the explained variance decreased from North to South. We therefore estimated new regression coefficients from the European discharge data and found that these were qualitatively similar to the original estimates from the UK. This suggests little variation across Europe in the hydrological effect of particular HOST classes, but decreasing influence of soil on BFI towards Southern Europe. Our preliminary study showed that pedological information is useful for characterising soil hydrology within Europe and the long-term discharge regime of catchments in Northern Europe. Based on these results, we draft a roadmap for a refined hydrological classification of European soils.

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