Search results for "Scaling"
showing 10 items of 754 documents
SURCOTES MARINES DANS LE GOLFE DU LION ET FORCAGES ATMOSPHERIQUES : VARIABILITE CONTEMPORAINE ET FUTURE (1950-2100)
2010
Sea surges in the Gulf of Lions are mainly forced by southerly and south-easterly winds. This regional-scale atmospheric circulation is leading by a strong zonal gradient between low pressure system over the Bay of Biscay and high pressure over central Europe. This synoptic-scale circulation mostly happens during “Greenland Above” weather regime. In the second half of the 20th century, a slow increase of the sea-level pressure over central Europe increased the probability of having “Greenland Above” weather types associated with a southerly atmospheric circulation in the Gulf of Lions, thus leading to strong surges. A linear regression is used to simulate the interannual variability of high…
Machine learning analysis of e-nose signal in early detection of mold contamination in buildings
2017
Grzyb rozwijający się na ścianach budynków jest głównym powodem zjawiska, które nazwano Syndromem Chorego Budynku. Wolne związki organiczne emitowane przez grzyby mogą być wykryte różnymi metodami, m.in. na podstawie chromatografii, ale także za pomocą matryc czujników gazowych. Wszystkie tego typu narzędzia generują sygnały elektryczne, które można analizować za pomocą odpowiednich technik statystycznych. Praca skupia się na zastosowaniu nadzorowanych i nienadzorowanych technik uczenia maszynowego w ocenie sygnału pochodzącego z elektronicznego nosa.
Multiparameter quantum critical metrology
2022
Single parameter estimation is known to benefit from extreme sensitivity to parameter changes in quantum critical systems. However, the simultaneous estimation of multiple parameters is generally limited due to the incompatibility arising from the quantum nature of the underlying system. A key question is whether quantum criticality may also play a positive role in reducing the incompatibility in the simultaneous estimation of multiple parameters. We argue that this is generally the case and verify this prediction in paradigmatic quantum many-body systems close to first and second order phase transitions. The antiferromagnetic and ferromagnetic 1-D Ising chain with both transverse and longi…
Classification of tall-forb vegetation in the Pamir-Alai and western Tian Shan Mountains (Tajikistan and Kyrgyzstan, Middle Asia)
2020
Aims: To complete the syntaxonomic scheme for tall-forb vegetation of the montane and alpine belts in the Pamir-Alai and western Tian Shan Mountains in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. Study area: Middle Asia: Tajikistan and Kyrgyzstan. Methods: A total of 244 relevés were sampled in 2013–2019 using the seven-degree cover-abundance scale of the Braun-Blanquet approach. These were classified with a modified TWINSPAN algorithm with pseudospecies cut-levels 0%, 5% and 25%, and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. NMDS was used to explore the relationsh…
Preference for Fractal-Scaling Properties Across Synthetic Noise Images and Artworks
2018
A large number of studies support the notion that synthetic images within a certain intermediate fractal-scaling range possess an intrinsic esthetic value. Interestingly, the fractal-scaling properties that define this intermediate range have also been found to characterize a vast collection of representational, abstract, and graphic art. While some have argued that these statistic properties only serve to maximize the visibility of the artworks’ spatial structure, others argue that they are intrinsically tied to the artworks’ esthetic appeal. In this study, we bring together these two threads of research and make a direct comparison between visual preference for varying fractal-scaling cha…
Mass-Metallicity Relation from Cosmological Hydrodynamical Simulations and X-ray Observations of Galaxy Groups and Clusters
2018
Recent X-ray observations of galaxy clusters show that the distribution of intra-cluster medium (ICM) metallicity is remarkably uniform in space and time. In this paper, we analyse a large sample of simulated objects, from poor groups to rich clusters, to study the dependence of the metallicity and related quantities on the mass of the systems. The simulations are performed with an improved version of the Smoothed-Particle-Hydrodynamics \texttt{GADGET-3} code and consider various astrophysical processes including radiative cooling, metal enrichment and feedback from stars and active galactic nuclei (AGN). The scaling between the metallicity and the temperature obtained in the simulations ag…
Cosmological hydrodynamical simulations of galaxy clusters: X-ray scaling relations and their evolution
2018
We analyse cosmological hydrodynamical simulations of galaxy clusters to study the X-ray scaling relations between total masses and observable quantities such as X-ray luminosity, gas mass, X-ray temperature, and $Y_{X}$. Three sets of simulations are performed with an improved version of the smoothed particle hydrodynamics GADGET-3 code. These consider the following: non-radiative gas, star formation and stellar feedback, and the addition of feedback by active galactic nuclei (AGN). We select clusters with $M_{500} > 10^{14} M_{\odot} E(z)^{-1}$, mimicking the typical selection of Sunyaev-Zeldovich samples. This permits to have a mass range large enough to enable robust fitting of the r…
The effect of plasticity in crumpling of thin sheets
2008
Bridging the gap between theoretical and experimental work to understand the effect of plasticity on the crumpling of thin sheets into a small volume has proved difficult. A realistic numerical model now makes a distinction between elastic and elasto-plastic behaviour. Crumpling a thin sheet of material into a small volume requires energy for creating a network of deformations such as vertices and ridges1,2. Scaling properties of a single elastic vertex3,4,5 or ridge have been analysed theoretically6,7,8, and crumpling of a sheet by numerical simulations1,9,10. Real materials are however elasto-plastic11,12,13,14,15 and large local strains induce irreversible plastic deformations. Hence, a …
Growth processes, dimensional parameters and scaling relationships of two conjugate sets of compactive shear bands in porous carbonate grainstones, F…
2012
Abstract Three main sets of deformation bands are identified in the Lower Pleistocene carbonate grainstones of Favignana Island (Italy). A bedding-parallel set is interpreted to contain compaction bands, based on the lack of evidence for shear. The other two sets are oriented at a high-angle to bedding, forming a conjugate pair comprised of compactive strike-slip shear bands. In this study, we focus on the compactive shear bands documenting their development, as well as analyzing their dimensional parameters and scaling relationships. Single compactive shear bands are thin, tabular zones with porosity less than the surrounding host rocks, and have thicknesses and displacements on the order …
Precipitation and Temperature
2016
Climatological studies indicate that climate change lead to an increase in the mean global temperature of around 0.5 °C until the end of the twentieth century. This warming impacts the atmospheric humidity, wind, radiation, and precipitation. However, the magnitude of changes is not equally distributed over the globe but differs markedly with regions, making a regionalization of the global information essential. The GLOWA-Danube project follows such a downscaling approach with the focus on the drainage basin of the Upper Danube River.