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3D random Voronoi grain-based models for simulation of brittle rock damage and fabric-guided micro-fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第6期6卷 506-521页

作者： E.Ghazvinian M.S.Diederichs R.Quey Geo Engineering Centre Queen's UniversityKingston ON Canada ecole nationale supérieure des mines de saint-Etienne CNRS UMR 5307 France

A grain-based distinct element model featuring three-dimensional （3D） Voronoi tessellations （randompoly-crystals） is proposed for simulation of crack damage development in brittle rocks. The grainboundaries in poly-crystal structure produced by Voronoi tessellations can represent flaws in intact rockand allow for numerical replication of crack damage progression through initiation and propagation ofmicro-fractures along grain boundaries. The Voronoi modelling scheme has been used widely in the pastfor brittle fracture simulation of rock materials. However the difficulty of generating 3D Voronoi modelshas limited its application to two-dimensional （2D） codes. The proposed approach is implemented inNeper, an open-source engine for generation of 3D Voronoi grains, to generate block geometry files thatcan be read directly into 3deC. A series of Unconfined Compressive Strength （UCS） tests are simulated in3deC to verify the proposed methodology for 3D simulation of brittle fractures and to investigate therelationship between each micro-parameter and the model＇s macro-response. The possibility of numericalreplication of the classical U-shape strength curve for anisotropic rocks is also investigated innumerical UCS tests by using complex-shaped （elongated） grains that are cemented to one another alongtheir adjoining sides. A micro-parameter calibration procedure is established for 3D Voronoi models foraccurate replication of the mechanical behaviour of isotropic and anisotropic （containing a fabric） rocks. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Numerical modelling 3D Voronoi tessellation Discrete element method Grain-based model Crack damage thresholds Fabric-guided micro-fracturing Anisotropy

The Lines of Lyman and the Titus-Bode Law Preferred Orbital of a Celestial Body

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Journal of Quantum Information Science 2015年第3期5卷 109-113页

作者： Raoul Charreton Diplomé ecole nationale supérieure des mines de Paris Paris France

We have proposed, thanks to a new model of the hydrogen atom [1], some explanation of the lines observed by Lyman in the spectrographic analysis of this atom. The model is based on a prequantum physics, itself founded on classical mechanics completed by the existence of a universal cloud of tiny particles called U. This cloud induces simultaneously and similarly electromagnetic and gravitational effects. This common origin creates a narrow link between how planets are arranged in a solar system, say the Titus-Bode law, and how the electrons are arranged in an atom, say the lines of Lyman. We describe what this link is in the following text and, more generally, what is the preferred orbit of an isolated celestial body.

关键词： Planets Lyman Titus-Bode

P-Li-Be Bearing Pegmatites of the South East Brazil

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International Journal of Geosciences 2012年第2期3卷 281-288页

作者： Essaid Bilal Adolf Heinrich Horn Fernando Machado de Mello ecole nationale supérieure des mines de saint-étienne CNRS-UMR6425 Saint-étienne France IA-departamento de Geociências da UFRRJ Rio de Janeiro Brazil IGC-UFMG Belo Horizonte Brazil

The P-Li-Nb pegmatites are located in the south of Brazil, in the states of Minas Gerais and Espirito Santos. They represent the largest pegmatite fields of Brazil and the richest in precious stones. Two types of pegmatites are characterized by their mineralogical characteristics and tectonic and magmatic relations. The first group occurred during a compressive deformation phase D1 about 582 Ma and 550℃ - 700℃ and 4 - 5 kb. The second pegmatites group was formed during the decompression phase D2 (520 - 500 Ma) of the Brasiliano metamorphic rock fusion. The geochemical parameters of the P-Li-Be bearing pegmatites of the first group show the same trend fractionation, as suggested by the mineralogical composition. The variation of tourmaline and columbite-tantalite composition of the first group game again applies a change of melt composition during the regional development of the pegmatites. A systematic compositional trend seems to suggest a petrogenetic link between the pegmatites of the region. The Fe/Mn ratio of tourmaline in samples of the first group shows the same behavior as in columbite-tantalite and garnets. The simple pegmatites are transiting north in the gem-rich pegmatites. The Fe/Mn ratio not only shows qualitatively the fractionation index, the degree of regional development, but also the internal development of the body. The ratio shows a negative correlation with lithium. The Co, Zn and Nb contents are rising at first group, but falling when starting crystallization of garnet, columbite-tantalite, and Behierit.

关键词： Gem Rich Pegmatite Phosphate Li Tourmaline Beryl Triphylite Ferrisiklerite Heterosite

Continuous frequency and phase spectrograms: a study of their 2D and 3D capabilities and application to musical signal analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 199-206页

作者： Laurent NAVARRO Guy COURBEBAISSE Jean-Charles PINOLI ecole nationale supérieure des mines de saint-Etienne Centre Ingénierie et Santé (CIS) and LPMG UMR 5148 CNRS 158 cours Fauriel 42023 Saint-Etienne cedex 2 France Medical Imaging Research Center (CREATIS-LRMN) UMR 5220 CNRS U630 INSERM Université Lyon 1 INSA Lyon Bat. Blaise Pascal 7 Av. Jean Capelle 69621 Villeurbanne France

A new lighting and enlargement on phase spectrogram （PS） and frequency spectrogram （FS） is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transform （STFT）. The main contribution is the construction of the 3D phase spectrogram （3DPS） and the 3D frequency spectrogram （3DFS）. These new tools allow such specific test signals as small slope linear chirp, phase jump case of musical signal analysis is reported. The main objective is to and small frequency jump to be analyzed. An application detect small frequency and phase variations in order to characterize each type of sound attack without losing the amplitude information given by power spectrogram

关键词： Frequency spectrogram (FS) Phase spectrogram (PS) Time-frequency representations Musical signals

Regional gradient observability for semilinear hyperbolic systems： HUM approach

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Control Theory and Technology 2018年第1期16卷 72-80页

作者： Adil KHAZARI Ali BOUTOULOUT Imad EL HARRAKI Sidi Mohamed Ben Abdellah University Ecole Nationale de Commerce et de gestion Fez Morocco TSI Team MACS Laboratory Faculty of Sciences Moulay Ismail University Meknes Morocco ecole nationale superieure des mines de Rabat Rabat Morocco

The paper aims to extend the notion of regional observability of the gradient to the semilinear hyperbolic case, in order to reconstruct the gradient of the initial conditions in a subregion w of the domain evolution Ω. We start with an asymptotically linear system, the approach is based on an extension of the Hilbert uniqueness method （HUM） and Schauder＇s fixed point theorem. The analysis leads to an algorithm which is successfully numerically implemented and illustrated with examples and simulations.

关键词： Distributed systems fixed point regional gradient observability regional reconstruction semilinear hyperbolic systems

Organic transistor platform with integrated microfluidics for in-line multi-parametric in vitro cell monitoring

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Microsystems & Nanoengineering 2017年第1期3卷 184-195页

作者： Vincenzo F.Curto Bastien Marchiori Adel Hama Anna-Maria Pappa Magali P.Ferro Marcel Braendlein Jonathan Rivnay Michel Fiocchi George G.Malliaras Marc Ramuz Róisín M.Owens department of Bioelectronics Ecole Nationale Supérieure des MinesCMP-EMSEMOC880 Avenue de MimetGardanne 13541France Flexible Electronics department Ecole Nationale Supérieure des Mines CMP-EMSEMOC880 Avenue de MimetGardanne 13541France department of Biomedical Engineering Northwestern UniversityEvanstonIL 60208USA

Future drug discovery and toxicology testing could benefit significantly from more predictive and multi-parametric readouts from in vitro *** the recent advances in the field of microfluidics,and more recently organ-on-a-chip technology,there is still a high demand for real-time monitoring systems that can be readily embedded with *** addition,multi-parametric monitoring is essential to improve the predictive quality of the data used to inform clinical studies that *** we present a microfluidic platform integrated with in-line electronic sensors based on the organic electrochemical *** goals are twofold,first to generate a platform to host cells in a more physiologically relevant environment(using physiologically relevant fluid shear stress(FSS))and second to show efficient integration of multiple different methods for assessing cell morphology,differentiation,and *** include optical imaging,impedance monitoring,metabolite sensing,and a wound-healing *** illustrate the versatility of this multi-parametric monitoring in giving us increased confidence to validate the improved differentiation of cells toward a physiological profile under FSS,thus yielding more accurate data when used to assess the effect of drugs or ***,this platform will enable high-content screening for in vitro drug discovery and toxicology testing and bridges the existing gap in the integration of in-line sensors in microfluidic devices.

关键词： bioelectronics in-line sensors in vitro microfluidics

Lithostratigraphy and Characterisation of Paleocene Limestones for Optimal Exploitation (Senegal, West Africa): Comparative Study of the Bandia and Popenguine Quarries

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Geomaterials 2023年第3期13卷 51-60页

作者： Mohamadou Moustapha Thiam Adama Dione Moumar Dieye Diakher Hélène Madioune Diodio Diouf ecole nationale supérieure des mines et de la Géologie Cheikh Anta Diop University Dakar Senegal Département de Géologie Cheikh Anta Diop University Dakar Senegal

Limestones of different facies in the Senegal basin are most commonly used as aggregates, regardless of their petrographic properties. These differences may influence their behaviour. The aim of this paper is to study the stratigraphy and characterise the limestones of the Bandia and Popenguine quarries. Sampling and geochemical and geotechnical characterisation were carried out on these limestones. The results show the presence of several very different facies in the Paleocene formation. The geochemical study shows that the Bandia limestones (Bd2) have the highest CaCO3 percentages (98.54%) and the highest SiO2 percentages were recorded in the Popenguine limestones (Pop2). The study also gives Mde values of 22.38 and LA of 22, which are acceptable for use in road construction. It is important to carry out a complete study in order to select the right materials for optimal use.

关键词： Stratigraphy Paleocene Geochemical Limestone Bandia Popenguine

Conducting polymer tattoo electrodes in clinical electro-and magneto-encephalography

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npj Flexible Electronics 2020年第1期4卷 36-44页

作者： Laura M.Ferrari Usein Ismailov Jean-Michel Badier Francesco Greco Esma Ismailova Center for MicroBiorobotics Istituto Italiano di Tecnologia56025 PontederaItaly The BioRobotics Institute Scuola Superiore Sant’Anna56025 PontederaItaly department of Bioelectronics Ecole Nationale Supérieure des Mines de Saint EtienneCMP-EMSEMOC1354 GardanneFrance Aix Marseille Univ INSERMINSInst Neurosci SystMarseilleFrance Institute of Solid State Physics NAWI GrazGraz University of Technology8010 GrazAustria department of Life Science and Medical Bioscience Waseda University169-8480 TokyoJapan

Temporary tattoo electrodes are the most recent development in the field of cutaneous *** have successfully demonstrated their performances in the monitoring of various electrophysiological signals on the *** epidermal electronic devices offer a conformal and imperceptible contact with the wearer while enabling good quality recordings over *** of brain activity in clinical practice face multiple limitations,where such electrodes can provide realistic technological solutions and increase diagnostics *** we present the performance of inkjet-printed conducting polymer tattoo electrodes in clinical electroencephalography and their compatibility with *** working mechanism of these dry sensors is investigated through the modeling of the skin/electrode impedance for better understanding of the biosignals transduction at this ***,a custom-made skin phantom platform demonstrates the feasibility of high-density recordings,which are essential in localizing neuropathological *** evaluations provide valuable input for the successful application of these ultrathin electronic tattoos sensors in multimodal brain monitoring and diagnosis.

关键词： polymer recording conformal

Epileptic seizure prediction based on EEG spikes detection of ictal-preictal states

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The Journal of Biomedical Research 2020年第3期34卷 162-169页

作者： Itaf Ben Slimen Larbi Boubchir Hassene Seddik Centre de Recherche et de Production Research Lab. Ecole Nationale Superieure des Ingenieurs de TunisUniversity of TunisTunis 1008Tunisia Laboratoire d'Informatique Avancee de saint-denis Research Lab. University of Paris 8Saint-DenisCedex 93526France

Epileptic seizures are known for their unpredictable ***,recent research provides that the transition to seizure event is not random but the result of evidence ***,a reliable method capable to detect these indications can predict seizures and improve the life quality of epileptic *** periods are generally characterized by epileptiform discharges with different changes including spike rate variation according to the shapes,spikes,and the *** this study,spike rate is used as the indicator to anticipate seizures in electroencephalogram(EEG) *** detection step is used in EEG signal during interictal,preictal,and ictal periods followed by a mean filter to smooth the spike *** maximum spike rate in interictal periods is used as an indicator to predict *** the spike number in the preictal period exceeds the threshold,an alarm is *** the CHB-MIT database,the proposed approach has ensured92% accuracy in seizure prediction for all patients.

关键词： electroencephalogram epilepsy seizure prediction spikes detection