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Numerical Study of Percolation and Seepage Behaviors in Ion-Adsorption-Type Rare Earth Ore Leaching Process

Mathematical Problems in engineering 2023年第1期2023卷

作者： Dianyu, E. Su, Zhongfang Zeng, Jia Yang, Liuyimei Li, Jing Xu, Qiang Wang, Lin Cui, Jiaxin Jiangxi Provincial Key Laboratory for Simulation and Modelling of Particulate Systems Jiangxi University of Science and Technology Nanchang330013 China International Institute for Innovation Jiangxi University of Science and Technology Nanchang330013 China Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou341000 China ARC Research Hub for Computational Particle Technology Department of Chemical and Biological Engineering Monash University ClaytonVIC3800 Australia State Key Laboratory of Multiphase Flow in Power Engineering Xi'An Jiaotong University Xi'an710049 China Delft University of Technology Delft Netherlands

Ionic rare earth ore is a type of featured rare earth ore in China. Its mining process suffers from a long leaching cycle and considerable consumption of leaching agents. Improving mining efficiency requires a sound physical understanding of the leaching process. In this study, the CFD-based numerical model is used to analyze the physical process of leaching through porous media formed by particles. The simulation results indicate that a lower packing porosity and smaller particles packed granular porous medium result in much larger energy dissipation during seepage, and the energy dissipation increases with seepage velocity. It is found that when the seepage velocity increases to a certain high value, the energy dissipation exceeds the value predicted by Darcy's law, which is mainly caused by liquid turbulence. Additionally, the effect of particle shape is examined. The results show that the granular medium composed of prolate particles causes larger energy dissipation than oblate particles, and spherical particles play the least role. This phenomenon may result from the particle shape affecting the area of the frontal contact surface between particles and liquid. The results provide new insights into the fundamental understanding of percolation and seepage behaviors in the ion-adsorption-type rare earth ore leaching process. © 2023 E. Dianyu et al.

关键词： Energy dissipation

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Using simulation and Digital Twins to Innovate: Are we Getting Smarter?

Using Simulation and Digital Twins to Innovate: Are we Getti...

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2021 Winter simulation Conference, WSC 2021

作者： Taylor, Simon J E Johansson, Bjorn Jeon, Sumin Lee, Loo Hay Lendermann, Peter Shao, Guodong Brunel University London Modelling Simulation Group Department of Computer Science Uxbridge United Kingdom Chalmers University of Technology Department of Industrial and Materials Science Gothenburg41296 Sweden Digital Industries Customer Services Siemens Pte Ltd Singapore National University of Singapore Department of Industrial Systems Engineering Management Singapore D-SIMLAB Technologies Pte Ltd Singapore National Institute of Standards and Technology Engineering Laboratory GaithersburgMD20899 United States

ISBN: (纸本)9781665433112

Digital Twins have recently emerged as a major new area of innovation. Digital Twins are often found at the core of 'smart' solutions that have also emerged as major areas of innovation. Modeling and simulation (MS) approaches create a model of a real-world system that is linked to data sources and is used to simulate and predict the behavior of its real-world counterpart. On the face of it Digital Twins and MS appear to be similar, if not the same. Is this actually the case? Are the two fields really separate or is Digital Twin research re-inventing the 'MS wheel'? To investigate these relationships, in this panel we will explore some contemporary innovations with Digital Twins and discuss whether or not Digital Twins is a contemporary 'refresh' or 'rebranding' of MS or if there are exciting new synergies. © 2021 IEEE.

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On the robustness of the in vivo cyanobacterial circadian clock

arXiv

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arXiv 2022年

作者： Fouego, Dorota Youmbi de Buyl, Sophie Laboratory of Modelling and Simulation in Engineering Biomimetics and Prototypes TWAS Research Unit Department of Physics Faculty of Science University of Yaoundé I Po. Box 812 Yaoundé Cameroon Applied Physics Research Group Physics Department Vrije Universiteit Brussel Brussels1050 Belgium Interuniversity Institute of Bioinformatics in Brussels Brussels1050 Belgium

We propose a revisited version of the in vivo model of the cyanobacterial circadian clock. Our aim is to address the lack of robustness predicted for the mutant cyanobacteria without transcriptional regulation of the original model. For this, we rely on an in vitro model of the clock describing explicitly the hexameric structure of the core protein of the clock. Our model is able to reproduce oscillatory behavior for the mutant, as observed experimentally, without finely tuned parameters. © 2022, CC BY-NC-SA.

关键词： Clocks

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Discret Wavelet Fingerprint Features for ANNs Classification Method

Discret Wavelet Fingerprint Features for ANNs Classification...

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E-Health and Bioengineering Conference (EHB)

作者： Andreea-Monica Dinca Lazarescu Simona Moldovanu Luminita Moraru The Modelling & Simulation Laboratory University Dunarea de Jos of Galati UGAL Galati Romania Faculty of Automation Computers Electrical Engineering and Electronics University Dunarea de Jos of Galati UGAL Galati Romania Department of Chemistry Faculty of Sciences and Environment Physics and Environment University Dunarea de Jos of Galati UGAL Galati Romania

ISBN: (数字)9781665485579

ISBN: (纸本)9781665485586

The current study examines the impact of discrete wavelet transforms (DWT) and their success rate in the fingerprint images classification. The analyzed fingerprint images belong to the FVC2004 database. Two datasets consist of 80 real images acquired using an optical sensor and 80 synthetic images, respectively, are built. Four discrete wavelet transform families (Coiflets, Symlets, Fejer - Korovkin and Biorthogonal) are implemented for one level of wavelet decomposition. For Low-Low (LL) and High-High (HH) sub-bands, the entropy and energy features are extracted as they contain rich descriptions of the pattern. For each dataset, eight features are extracted, for each image. To reduce the dimensionality of the feature space, the Principal Component Analysis (PCA) is used. The first three principal components (PCs) fed a neural network classifier. The Radial Base Function Neural Network (RBFNN) model efficiently classified the fingerprint images based on PCs obtained for LL frequency level images features, with an accuracy of 88.13% and sensitivity of 95%.

关键词： Image matching Biological system modeling Neural networks Transforms Fingerprint recognition Feature extraction Entropy

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3D Brain Tumor Volume Reconstruction and Quantification using MRI Multi-modalities Brain Images

3D Brain Tumor Volume Reconstruction and Quantification usin...

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E-Health and Bioengineering Conference (EHB)

作者： Lenuta Pana Simona Moldovanu Luminita Moraru The Modelling & Simulation Laboratory University Dunarea de Jos of Galati UGAL Galati Romania Faculty of Automation Computers Sciences Electronics and Electrical Engineering Dunarea de Jos University of Galati Galati Romania Department of Chemistry Physics and Environment Faculty of Sciences and Environment University Dunarea de Jos of Galati UGAL Galati Romania

ISBN: (数字)9781665485579

ISBN: (纸本)9781665485586

Brain tumor volume quantification is not possible with magnetic resonance imaging (MRI) non-invasive imaging systems. Usually, the brain MR imaging modality is based on four modalities T1, T1ce (contrast-enhanced), T2, and FLAIR (Fluid-Attenuated Inversion Recovery) highlighting various complex brain structure. The aim of this study is to develop an automated brain tumor segmentation method to allow an effective 3D tumor reconstruction and volume quantification. The Local Graph Cut (LGC) and Flood fill (FF) segmentation tools are used. A 3D reconstruction is performed using the open-source ImageJ image processing package. To assess the brain tumor segmentation accuracy a 3D Dice score is used. This extensive study is conducted on the MICCAI BraTS2020 dataset and shows that the proposed model obtains good results. To evaluate the final full segmentation of 3D volume accuracy, we use three brain modalities, namely T1 and T2 weighted, and T1ce scans. Also, to measure accuracy of segmentation we take the advantage of the existing ground truth image dataset. We find an average Dice score of 0.501 ± 0.128 for T2-weighted images and LGC algorithm. Also, there are not important differences between the results provided by investigated algorithms for all images types. The 3D reconstruction and volumetric analysis via 2D segmented slices produce realistic shape samples. The computed volumes are in the limit of 71% from the tumor volume computed using the ground truth images.

关键词： Image segmentation Three-dimensional displays Shape Magnetic resonance imaging Surgery Prediction algorithms Brain modeling

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Multi-scale modelling of gas flow in nanoscale pore space with fractures

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Journal of Rock Mechanics and Geotechnical engineering 2020年第1期12卷 32-40页

作者： Qingrong Xiong Diansen Yang Weizhong Chen Research Centre for Radwaste&Decommissioning and Modelling&Simulation Centre Dalton Nuclear InstituteUniversity of ManchesterManchesterM139PLUK School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

In this work,a multi-scale pore network with fractures is developed against experimental data in a wide range of degrees of water *** pore network is constructed based on the measured microstructure information at several length *** gas transport is predicted by different gas transport equations(***,dusty gas model(DGM),Civan and Klinkenberg),which can consider the fundamental physics mechanisms in tight porous media,such as Knudsen diffusion and viscous ***,the model is applied to simulating the gas permeability of the Callovo-Oxfordian(COx)*** predicted gas permeability is basically in good agreement with the experimental data under different degrees of water *** the effects of micro-fissures are *** results suggest that this model can predict the gas flow in other tight porous media as well and can be applied to other fields such as carbon capture and storage.

关键词： Pore network Nanopores Apparent gas permeability Callovo-Oxfordian(COx)claystone

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Realization of inverse-design magnonic logic gates

arXiv

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arXiv 2024年

作者： Zenbaa, Noura Majcen, Fabian Abert, Claas Bruckner, Florian Mauser, Norbert J. Schrefl, Thomas Wang, Qi Suess, Dieter Chumak, Andrii V. University of Vienna Faculty of Physics Vienna1090 Austria University of Vienna Vienna Doctoral School in Physics Vienna1090 Austria Research Platform MMM "Mathematics-Magnetism-Materials" University of Vienna Vienna1090 Austria Faculty of Mathematics University of Vienna Vienna1090 Austria Center for Modelling and Simulation Donau-Universität Krems Wiener Neustadt2700 Austria School of Physics Hubei Key Laboratory of Gravitation and Quantum Physics Institute for Quantum Science and Engineering Huazhong University of Science and Technology Wuhan430074 China

Magnonic logic gates represent a crucial step toward realizing fully magnonic data processing systems without reliance on conventional electronic or photonic elements. Recently, a universal and reconfigurable inverse-design device has been developed, featuring a 7×7 array of independent current loops that create local inhomogeneous magnetic fields to scatter spin waves in a Yttrium-Iron-Garnet film. While initially used for linear RF components, we now demonstrate key non-linear logic gates, NOT, OR, NOR, AND, NAND, and a half-adder, sufficient for building a full processor. In this system, binary data ("0" and "1") are encoded in the spin-wave amplitude. The contrast ratio, representing the difference between logic states, achieved values of 34, 53.9, 11.8, 19.7, 17, and 9.8 dB for these gates, respectively. © 2024, CC BY.

关键词： Spin waves

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An invisible DWT watermarking algorithm using noise removal with application to dermoscopic images 9

An invisible DWT watermarking algorithm using noise removal ...

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9th International Conference on Mathematical Modeling in Physical Sciences, IC-MSQUARE 2020

作者： Moldovanu, S. Michis, F.A. Moraru, L. Dunarea de Jos University of Galati Department of Computer Science and Information Technology Faculty of Automation Computers Sciences Electronics and Electrical Engineering 2 Stiintei Street GalatiRO-800210 Romania Department of Chemistry Physics and Environment Faculty of Sciences and Environment Dunarea de Jos University of Galati 47 Domneasca Street Galati800008 Romania Dunarea de Jos University of Galati Modelling and Simulation Laboratory Galati Romania

A new approach for the digital watermarking process is proposed to be part of the pre-processing stage of a computer-aided diagnosis system. We propose to embed a denoised image acting as the watermark image in the original host image with the final goal of improving the quality of demoscopic images for further image processing operation related to CAD. The proposed algorithm uses Discrete Wavelet Transform (DWT) corroborated with some basic properties of Human Visual System such as Contrast Sensitive Function (CSF) and Noise Visibility Function (NVF) with the goal of correlating the texture properties and noise. This approach hides the watermark (i.e. denoised version of the host image) in high-pass subbands that are focused on image features. The main concern is to evaluate the distortion produced to the host image by watermarking and an objective quality measure function, i.e. Weighted Peak Signal-to-Noise Ratio (WPSNR), is used to evaluate the existing differences between the original and watermarked images. The proposed approach is tested using the available skin lesion images from the digital image archive of the Department of Dermatology of the University Medical Center Groningen. The experiment results show the improved performance of the proposed scheme against a 3 × 3 median filtering attack in comparison with the a 5 × 5 median filtering attack. © Published under licence by IOP Publishing Ltd.

关键词： Discrete wavelet transforms

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Dynamics of an Array Mechanical Arms Coupled Each to a Fitzhugh-Nagumo Neuron

Research Square

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Research Square 2021年

作者： Mbeunga, N. Kouami Bonaventure, Nana Woafo, Paul Laboratory of Modelling and Simulation in Engineering Biomimetics and Prototypes Faculty of Science University of Yaounde I PO Box 812 Yaounde Cameroon Department of Physics Higher Teacher Training College University of Bamenda PO Box 39 Bamenda Cameroon

In this work, an array of electromechanical systems driven by an electrical line of Fitzhugh-Nagumo neuron is analyzed. It is shown that a single electromechanical system can display different dynamical behaviors such as single and multiple pulse generation, transient chaos, permanent chaos, and antimonotonicity according to the system parameters. In the case of an array of the electromechanical system constituted of a series of coupled discrete Fitzhugh-Nagumo neuron, the numerical simulation shows that as the action potential flows in the discrete array, each electromechanical system executes a pulse-like motion coming at each resting state as the electrical signal passes the node. The electromechanical system analyzed can be seen as a model for multiperiodic actuation processes or a leg model in a millipede system. Furthermore, this line can also carry an envelope of action potential and can be useful for various kinds of information processing systems. © 2021, CC BY.

关键词： Neurons

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Improved Classification of Benign and Malignant Breast Lesions Based on Contrast Manipulation and Gradient Map

Improved Classification of Benign and Malignant Breast Lesio...

引用

E-Health and Bioengineering Conference (EHB)

作者： Iulia–Nela Anghelache Nastase Simona Moldovanu Luminita Moraru The Modelling & Simulation Laboratory University Dunarea de Jos of Galati UGAL Galati Romania Department of Computer Science and Information Technology Faculty of Automation Computers Electrical Engineering and Electronics University Dunarea de Jos of Galati UGAL Galati Romania Department of Chemistry Physics and Environment Faculty of Sciences and Environment University Dunarea de Jos of Galati UGAL Galati Romania

ISBN: (数字)9781665485579

ISBN: (纸本)9781665485586

This study proposes an approach to enhance the contrast breast ultrasound (BUS) images with the preservation of the finer details. The main idea is to use the relevant and most important features in the classification of BUS images as benign or malignant. Among the contrast manipulation techniques, both linear under- and overexposure methods, contrast limiting adaptive histogram equalization (CLAHE) method and homomorphic filtering are used. The gradient maps of original images are generated for further analysis. Also, the gradient maps of original images are improved by the local mean subtraction and divisive normalization. Eight structural features are extracted from each gradient map image type. The extracted features feed a Random Forest (RF) classifier to determine their relevance for BUS images classification. An accuracy of 97.12% has been obtained for improved gradient map images and 93.03% for gradient map images.

关键词： Histograms Ultrasonic imaging Limiting Breast Feature extraction Lesions Standards

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