Academic literature on the topic 'Multiphysic imager'
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Journal articles on the topic "Multiphysic imager"
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Zolotukhin P. A., Il'ichev E. A., Petrukhin G. N., Popov A. V., Rychkov G. S., and Teverovskaya E. G. "Calculation and optimization of the limiting characteristics of a single-channel dual-spectrum image receiver of objects emitting in the ultraviolet range." Technical Physics 92, no. 9 (2022): 1254. http://dx.doi.org/10.21883/tp.2022.09.54691.97-22.
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A single-channel, two-spectral image receiver of objects emitting in UV radiation, made in the image intensifier tube architecture, was proposed and investigated. With the help of the COMSOL Multiphysics software package, search optimal measurements of the potential on the elements of the image receiver (silicon membrane, germanium and diamond photocathode, MCP input and output sensors) were implemented, which provides the possibility of registering and presence of UV objects in relation to the terrain. Keywords: image intensifier tube, diamond photocathode, germanium photocathode, ultraviolet radiation, object imager, photoelectron emission, secondary electron emission.
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Kim, Yoon Young, Jae Chun Ryu, Eunil Kim, Hyoungkee Kim, and Byungseong Ahn. "A Variational Art Algorithm for Image Generation." Leonardo 49, no. 3 (June 2016): 226–31. http://dx.doi.org/10.1162/leon_a_00914.
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The authors propose a variational art algorithm: a virtual system-based optimization algorithm developed for generating images. Observing that the topology optimization method used for multiphysics system design can produce two- or three-dimensional layouts without baselines, the authors propose to expand it beyond engineering applications for generating images. They have devised a virtual physical system—a heat-path system—that “interprets” the optimization-based process of image generation as the simultaneous drawing of multiple strokes in a painting.
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Leslie, Nathaniel, and Janine Mauzeroll. "Simulating Scanning Electrochemical Microscopy Images of Arbitrarily Shaped Reactive Sites without a Site-Specific Model." ECS Meeting Abstracts MA2022-01, no. 46 (July 7, 2022): 1947. http://dx.doi.org/10.1149/ma2022-01461947mtgabs.
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Scanning electrochemical microscopy (SECM) yields two-dimensional electrochemical images when the current at a microelectrode is recorded as it moves above a surface generating redox species. As SECM images are often systematically compared to microstructure features obtained by electron microscopy there is a clear need to find ways to integrate electron microscopy images into SECM image simulations. Recently, finite element method simulations of sites where electrochemical reactions take place is employed to evaluate reactive feature size.[1] Current models move the microelectrode or the reacting surface, continuously changing the geometry of the simulation and thus requiring re-meshing, which increases the computation time. We present a modeling approach by which SECM images of arbitrarily-shaped reactive sites can be simulated using a grid of pixels that can be turned ‘on’ and ‘off’ using COMSOL® multiphysics. Specifically, COMSOL®’s Java API is used to change the selection of pixels that are turned ‘on’ to simulate the movement of the electrode without changing the geometry of the simulation. The mesh can be re-used for each data-point in the image, dramatically reducing the time needed to simulate SECM images. This work also presents a mostly automated workflow for using an electron microscopy image of a reactive site to determine which pixels should be turned ‘on’ and fitting the kinetics at these pixels by simulating their SECM image. [1] L. I. Stephens, N. A. Payne, S. A. Skaanvik, D. Polcari, M. Geissler, J. Mauzeroll, Evaluating the Use of Edge Detection in Extracting Feature Size from Scanning Electrochemical Microscopy Images. Analytical Chemistry 2019, 91, 3944-3950.
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Luo, Yongzhen, Guocong Lin, Xidong Ding, and Tao Su. "The detection of buried nanopillar based on electrostatic force microscopy simulation." AIP Advances 12, no. 6 (June 1, 2022): 065211. http://dx.doi.org/10.1063/5.0088843.
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Based on electrostatic force microscopy (EFM), the image of nano-objects buried below the surface was numerically simulated by using COMSOL Multiphysics® software. The shape and the approximate size of the buried pillar could be obtained from the simulated EFM images. It was demonstrated that the detection of the buried nanopillar based on EFM was feasible. When the image data measured by EFM were used as the input data for comparison with the simulated data, the three unknowns (relative dielectric constant ε r, p, buried depth d, and side length l) of the buried pillar could be obtained. In this paper, the simulated EFM image data were used as the input data. The accurate values of ε r, p, d, and l of the buried nanopillar could be obtained by comparing the input data with the data simulated with other known parameters. The results showed that EFM was a good candidate as a kind of three dimensional nanoscale tomographic technique. It could map the physical properties of buried nanomaterials, which are relevant to modern integrated circuits.
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Yang, Dan, Jiahua Liu, Yuchen Wang, Bin Xu, and Xu Wang. "Application of a Generative Adversarial Network in Image Reconstruction of Magnetic Induction Tomography." Sensors 21, no. 11 (June 3, 2021): 3869. http://dx.doi.org/10.3390/s21113869.
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Image reconstruction of Magnetic induction tomography (MIT) is an ill-posed problem. The non-linear characteristics lead many difficulties to its solution. In this paper, a method based on a Generative Adversarial Network (GAN) is presented to tackle these barriers. Firstly, the principle of MIT is analyzed. Then the process for finding the global optimum of conductivity distribution is described as a training process, and the GAN model is proposed. Finally, the image was reconstructed by a part of the model (the generator). All datasets are obtained from an eight-channel MIT model by COMSOL Multiphysics software. The voltage measurement samples are used as input to the trained network, and its output is an estimate for image reconstruction of the internal conductivity distribution. The results based on the proposed model and the traditional algorithms were compared, which have shown that average root mean squared error of reconstruction results obtained by the proposed method is 0.090, and the average correlation coefficient with original images is 0.940, better than corresponding indicators of BPNN and Tikhonov regularization algorithms. Accordingly, the GAN algorithm was able to fit the non-linear relationship between input and output, and visual images also show that it solved the usual problems of artifact in traditional algorithm and hot pixels in L2 regularization, which is of great significance for other ill-posed or non-linear problems.
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Grevcev A. S., Zolotukhin P. A., Il'ichev E. A., Petruhin G. N., Popov A. V., and Rychkov G. S. "The thermal image receiver realized in the electron-optical converter architecture." Technical Physics 92, no. 4 (2022): 419. http://dx.doi.org/10.21883/tp.2022.04.53597.270-21.
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An innovative design is considered, and the results of analysis and calculations of the characteristics of a thermal image receiver (3-15 microns), made in the electron-optical converter architecture, are presented. For the sensor-converting pyroelectric unit of the electron-optical converter, the spatial dependences of the electric field strengths and the values of the electric potentials on the spontaneous polarization of the film substance are calculated. Estimates are obtained and the characteristics of thermal-field-induced polarization of various pyroelectric films are discussed. The temperature dependences of the polarization characteristics of a number of pyroelectric films are calculated using the finite element method in the COMSOL Multiphysics software package. Possible contributions of the piezoelectric effect to the picture of the distribution of electric potentials from the thermal polarization of pyroelectric films are taken into account. Estimates are obtained for the limiting values of the main instrument characteristics of the electron-optical converter. Keywords: the electron-optical converter, spontaneous polarization, pyroelectric, bolometric thermal imagers, pyroelectric thermal imagers.
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Yang, Liu, Chun Guang Xu, Xiang Hui Guo, Xin Liang Li, Qi Lin, Ye Huang, and Hao Yu Sun. "Multi-Objects Ultrasonic Tomography by Immersion Circular Array." Advanced Materials Research 1006-1007 (August 2014): 879–83. http://dx.doi.org/10.4028/www.scientific.net/amr.1006-1007.879.
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The typical application of ultrasonic tomography is the determination of process parameters like component flow rates and material fractions in industrial environment. Another promising application is non-invasive health monitoring in medical care. Both acoustic attenuation and acoustic impedance inhomogeneity are the main physical quantities that are used to reconstruct the image. When transmission ultrasonic waves are shadowed by hard tissue because of severe attenuation, the reflection mode can be an effective supplement. This paper provides multi-objects reconstruction images by reflection ultrasonic tomography, demonstrating the multi-objects imaging capability of an immersion circular array system. The circular array consists of 36 ultrasonic transducers with 0.5MHz frequency which are ring arranged and embedded in the container wall to serve as both transmitter and receiver. Each time one transducer is fired and in the meantime other transducers are enabled to receive signals. Ultrasonic transmitting, propagating and receiving of the circular array system are simulated by COMSOL Multiphysics® software, after that a series of image reconstructions of the objects with different numbers are obtained through ellipse algorithm.
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Sukor, Nur Syafiqah Amirah Ab, Fatinah Mohd Rahalim, Juliza Jamaludin, and Normaliza Ab Malik. "A Conceptual Model of Dual-Mode Tomography Technique for Dental Diagnostics: Ultrasound and Light Propagation Analysis." Journal of Physics: Conference Series 2641, no. 1 (November 1, 2023): 012008. http://dx.doi.org/10.1088/1742-6596/2641/1/012008.
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Abstract Many advanced imaging modalities, such as magnetic resonance imaging (MRI), X-ray Computed Tomography, Positron Emission Tomography (PET), Ultrasound, Single Photon Emission Computed Tomography (SPECT), and the most recent, Optical Coherence Tomography (OCT), have been developed for identifying dental tissues images and detecting changes in early carious lesions. Some modalities use high doses of radiation and energy to obtain more information, which may be harmful to patient’s health. Most early commercial OCTs had drawbacks such as its bulky size and limited image resolution. In order to overcome these concerns, this paper presents a dual-mode tomography technique that combines OCT and ultrasound method using the COMSOL Multiphysics. The application of an ultrasound device helps overcome the limitation of OCT in detecting the penetration depth of a caries lesion. Several simulations were performed to analyse the light and ultrasonic propagated waves with different diameters of carious lesions. In response to this goal, the combination data of OCT and ultrasound provide a 3D image which offers the best approach for displaying and examining changes in the oral cavity.
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Razali, Nazirah Mohd, Muhammad Quisar Lokman, Siti Nur Fatin Zuikafly, Fauzan Ahmad, and Hafizal Yahaya. "Simulation of Self-Image Interference in Single Mode-No-Core-Single Mode Fiber with COMSOL Multiphysics®." Journal of Physics: Conference Series 2411, no. 1 (December 1, 2022): 012019. http://dx.doi.org/10.1088/1742-6596/2411/1/012019.
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Abstract Self-image interference in a single mode-no-core-single mode fiber plays an important role especially for length optimization before acting as a sensor. The interference can be observed through optical simulation software. Past literature has successfully demonstrated the interference via COMSOL Multiphysics®, but the simulation was not restricted to the use of important domains and settings such as perfectly matched layer and surrounding domain causing imprecise simulation results. This paper proposes a simulation of self-image interference in a single mode-no-core-single mode fiber by using the wave-optics module in COMSOL Multiphysics® software. The beam propagation method is used to observe the self-image interference for different self-image indexes ranging from one to four indexes while the self-image length is obtained from the theoretical calculation before a simulation is carried out. The results show that accurate results can be obtained with restricted simulation settings. The number of the self-image index and self-image length produced by the simulation are similar to the calculation. The self-image point is located exactly at the calculated length with a four-decimal point 0.0000 difference, thus overcoming the limitation of the simulated previous work. In the future, the simulation settings and results can be used for reference to simulate the single mode- no-core-single mode fiber structure.
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Chin, Lixin, Andrea Curatolo, Brendan F. Kennedy, Barry J. Doyle, Peter R. T. Munro, Robert A. McLaughlin, and David D. Sampson. "Analysis of image formation in optical coherence elastography using a multiphysics approach." Biomedical Optics Express 5, no. 9 (August 1, 2014): 2913. http://dx.doi.org/10.1364/boe.5.002913.
Full textDissertations / Theses on the topic "Multiphysic imager"
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Garcia, Marine. "Développement d’une plateforme d’imagerie pour la caractérisation du transfert de masse dans les microsystèmes : application aux piles à combustible microfluidiques." Electronic Thesis or Diss., Paris, HESAM, 2024. http://www.theses.fr/2024HESAE007.
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Les piles à combustible sont des dispositifs qui transforment l'énergie stockée dans un oxydant et un réducteur en électricité grâce à des réactions électrochimiques. La technologie la plus mature pour réaliser cette conversion est la pile à hydrogène à membrane échangeuse de protons (PEMFC), mais d'autres systèmes alternatifs émergent. En particulier, les piles à combustible microfluidiques (PCM) ont permis de s’affranchir des problématiques liées à l’utilisation d’une membrane et du stockage gazeux grâce à l’utilisation de réactifs liquides à température et pression ambiante. Les dimensions du canal (1-5 mm de large et 20-100 µm de haut) permettent un écoulement co-laminaire des deux réactifs et de l’électrolyte liquides dans un micro-canal contenant les électrodes. Les PCMs n'ont donc pas de membrane et leurs performances sont dirigées par le transport de charges et de masse.À ce jour, il est difficile de caractériser expérimentalement tous les phénomènes physiques qui ont lieu dans la PCM car les méthodes existantes sont plutôt basées sur la caractérisation électrochimique. Ces méthodes permettent d'avoir une caractérisation globale du système mais ne fournissent pas d'informations précises sur les phénomènes de transport de masse dans le canal. Pour étudier le transport de masse, la modélisation numérique est généralement utilisée et permet de simuler le champ de concentration et les performances de la PCM pour différentes architectures et conditions opératoires. Toutefois, l'utilisation de ces modèles repose sur la connaissance de paramètres in-situ tels que le coefficient de diffusion D et le coefficient de réaction k0. Dans les travaux numériques, ces paramètres sont généralement approximés, ce qui permet une appréhension plutôt qualitative des phénomènes de transport. De plus, ces études numériques n'ont à ce jour pas été vérifiées avec des études expérimentales.Ainsi, le principal verrou scientifique de cette thèse repose sur le développement de méthodes d'imagerie quantitatives pour la caractérisation du champ de concentration dans une PCM en fonctionnement.Pour répondre à ce besoin, une plateforme d'imagerie basée sur la spectroscopie ainsi que trois méthodes de caractérisation ont été développées dans cette thèse. Dans un premier temps, les travaux se sont concentrés sur le développement d'un banc de spectroscopie pour étudier le phénomène d'interdiffusion. Cette étude a permis d'estimer le coefficient de diffusion du permanganate de potassium dans l'acide formique. Ces solutions ont été spécifiquement choisies car ceux sont celle utilisées dans la PCM développées pour la suite de l’étude.Le banc de spectroscopie a ensuite été adapté pour étudier le champ de concentration 2D en régime permanent d'une PCM en fonctionnement. Un modèle analytique du transfert de masse (advection/réaction/diffusion) couplé au champ de concentration 2D a ainsi permis de déterminer le taux de réaction. Les variations de concentration mises en jeu étant parfois très faibles (quelques micro-moles), une autre technique de caractérisation a été mis en place pour diminuer le bruit de mesure.Afin d'améliorer le rapport signal sur bruit, une méthode basée sur la modulation du champ de concentration a été développée. La démodulation du signal a permis de réduire significativement le bruit et des concentrations de 20 µM ont ainsi été estimées. Un modèle analytique décrivant le champ modulé a été établi afin d'implémenter une méthode inverse. La méthode proposée a permis de retrouver le taux de réaction associé à la variation de concentration.En conclusion, les méthodes de caractérisation proposées dans cette thèse permettent d'estimer quantitativement le transfert de masse et la cinétique de réaction à partir du champ de concentration 2D d'une PCM en fonctionnement. Cette technique a été appliquée au PCM, mais elle peut être transférée à un système micrométrique dans lequel les phénomènes de diffusion-advection-réaction ont lieuFuel cells are devices that convert the energy stored in an oxidant and a reductant into electricity through electrochemical reactions. The most mature technology for this conversion is the proton exchange membrane fuel cell (PEMFC), but other alternative systems are emerging. In particular, microfluidic fuel cells (MFCs) have overcome the problems associated with the use of a membrane and gas storage by using liquid reagents at ambient temperature and pressure. The dimensions of the channel (1-5 mm wide and 20-100 µm high) allow co-laminar flow of the two liquid reagents and the electrolyte in a microchannel containing the electrodes. Therefore, PCMs do not need membrane to separate reactants and performances are driven by charge and mass transport.Experimental characterization of all the physical phenomena involved in PCMs is difficult because actuals methods are more based on electrochemical characterisation. These methods provide an overall characterisation of the system but they do not give precise information on the mass transport phenomena occurring in the channel. To investigate concentration field, numerical modelling is generally used. Numerical methods evaluate the impact of the geometry or the operating conditions on MFC performances. However, the use of these models relies on the knowledge of in-situ parameters such as the diffusion coefficient D and the reaction rate k0. In numerical studies, these parameters are generally approximated leading to a qualitative understanding of the transport phenomena. Furthermore, these numerical studies have not yet been verified by experimental studies.Thus, the main scientific challenge of this thesis is to develop quantitative imaging methods for characterising the concentration field in an operating PCM.To meet this need, an imaging platform based on spectroscopy and three characterisation methods were developed in this thesis. First of all, the work focused on developing an experimental setup based on spectroscopy to study the interdiffusion phenomenon. This study reports the estimation of the diffusion coefficient of potassium permanganate in formic acid. These solutions were specifically chosen because they are used in the PCM developed for the rest of the study.The imaging plateform was then adapted to study the in operando MFC 2D concentration field in steady-state. An analytical mass transfer model (advection/reaction/diffusion) coupled to the 2D concentration field was used to determine the reaction rate. As the concentration variations involved can be very small (few micro-moles), another characterisation technique was implemented to reduce the measurement noise.To improve the signal-to-noise ratio, a method based on modulation of the concentration field was developed. Demodulation of the signal significantly reduced the noise and concentrations of 20 µM were estimated. An analytical model describing the modulated field was established in order to implement an inverse method. The proposed method made it possible to recover the reaction rate associated with the concentration variation.To conclude, the proposed characterisation methods enable the estimation of the mass transfer and the reaction kinetics using the 2D concentration field from an in operando MFC. This technique has been applied to the MFC, but it can be transferred to a micrometric system in which diffusion-advection-reaction phenomena take place
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Qin, Yingying. "Early breast anomalies detection with microwave and ultrasound modalities." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG058.
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Résumé: L'imagerie du sein est développée en associant données micro-ondes (MW) et ultrasonores (US) afin de détecter de manière précoce des tumeurs. On souhaite qu'aucune contrainte soit imposée, le sein étant supposé libre. Une 1re approche utilise des informations sur les frontières des tissus provenant de données de réflexion US. La régularisation intègre que deux pixels voisins présentent des propriétés MW similaires s'il ne sont pas sur une frontière. Ceci est appliqué au sein de la méthode itérative de Born distordue. Une 2de approche implique une régularisation déterministe préservant les bords via variables auxiliaires indiquant si un pixel est ou non sur un bord. Ces variables sont partagées par les paramètres MW et US. Ceux-ci sont conjointement optimisés à partir d'ume approche de minimisation alternée. L'algorithme met alternitivement à jour contraste US, marqueurs, et contraste MW. Une 3e approche implique réseaux de neurones convolutifs. Le courant de contraste estimé et le champ diffusé sont les entrées. Une structure multi-flux se nourrit des données MW et US. Le réseau produit les cartes des paramètres MW et US en temps réel. Outre la tâche de régression, une stratégie d'apprentissage multitâche est utilisée avec un classificateur qui associe chaque pixel à un type de tissu pour produire une image de segmentation. La perte pondérée attribue une pénalité plus élevée aux pixels dans les tumeurs si il sont mal classés. Une 4e approche implique un formalisme bayésien où la distribution a posteriori jointe est obtenue via la règle de Bayes ; cette distribution est ensuite approchée par une loi séparable de forme libre pour chaque ensemble d'inconnues pour obtenir l'estimation. Toutes ces méthodes de résolution sont illustrées et comparées à partir d'un grand nombre de données simulées sur des modèles synthétiques simples et sur des coupes transversales de fantômes mammaires numériques anatomiquement réalistes dérivés d'IRM dans lesquels de petites tumeurs artificielles sont inséréesImaging of the breast for early detec-tion of tumors is studied by associating microwave (MW) and ultrasound (US) data. No registration is enforced since a free pending breast is tackled. A 1st approach uses prior information on tissue boundaries yielded from US reflection data. Regularization incorporates that two neighboring pixels should exhibit similar MW properties when not on a boundary while a jump allowed otherwise. This is enforced in the distorted Born iterative and the contrast source inversion methods. A 2nd approach involves deterministic edge preserving regularization via auxiliary variables indicating if a pixel is on an edge or not, edge markers being shared by MW and US parameters. Those are jointly optimized from the last parameter profiles and guide the next optimization as regularization term coefficients. Alternate minimization is to update US contrast, edge markers and MW contrast. A 3rd approach involves convolutional neural networks. Estimated contrast current and scattered field are the inputs. A multi-stream structure is employed to feed MW and US data. The network outputs the maps of MW and US parameters to perform real-time. Apart from the regression task, a multi-task learning strategy is used with a classifier that associates each pixel to a tissue type to yield a segmentation image. Weighted loss assigns a higher penalty to pixels in tumors when wrongly classified. A 4th approach involves a Bayesian formalism where the joint posterior distribution is obtained via Bayes’ rule; this true distribution is then approximated by a free-form separable law for each set of unknowns to get the estimate sought. All those solution methods are illustrated and compared from a wealth of simulated data on simple synthetic models and on 2D cross-sections of anatomically-realistic MRI-derived numerical breast phantoms in which small artificial tumors are inserted
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Cenni, Fabio. "Modélisation à haut niveau de systèmes hétérogènes, interfaçage analogique /numérique." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00721972.
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L'objet de la thèse est la modélisation de systèmes hétérogènes intégrant différents domaines de la physique et à signaux mixtes, numériques et analogiques (AMS). Une étude approfondie de différentes techniques d'extraction et de calibration de modèles comportementaux de composants analogiques à différents niveaux d'abstraction et de précision est présentée. Cette étude a mis en lumière trois approches principales qui ont été validées par la modélisation de plusieurs applications issues de divers domaines: un amplificateur faible bruit (LNA), un capteur chimique basé sur des ondes acoustiques de surface (SAW), le développement à plusieurs niveaux d'abstraction d'un capteur CMOS vidéo, et son intégration dans une plateforme industrielle. Les outils développés sont basés sur les extensions AMS du standard IEEE 1666 SystemC mais les techniques proposées sont facilement transposables à d'autres langages tels que VHDL-AMS ou Verilog-AMS utilisés en conception de dispositifs mixtes.
Book chapters on the topic "Multiphysic imager"
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Zhdanov, Michael S. "Simultaneous Processing and Fusion of Multiphysics Data and Images." In Advanced Methods of Joint Inversion and Fusion of Multiphysics Data, 259–74. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-6722-3_14.
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Gentilal, Nichal, Ricardo Salvador, and Pedro Cavaleiro Miranda. "A Thermal Study of Tumor-Treating Fields for Glioblastoma Therapy." In Brain and Human Body Modeling 2020, 37–62. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45623-8_3.
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AbstractTumor-treating fields (TTFields) is an antimitotic cancer treatment technique used for glioblastoma multiforme (GBM) and malignant pleural mesothelioma. Although the frequency used is not as high as in hyperthermia, temperature increases due to the Joule effect might be meaningful given the necessary time that these fields should be applied for. Post hoc analysis of the EF-11 clinical trial showed higher median overall survival in patients whose compliance was at least 18 h per day. To quantify these temperature increases and predict the thermal impact of TTFields delivery to the head, we used a realistic model created from MR images segmented in five tissues: scalp, skull, CSF, gray matter (GM), and white matter (WM). Through COMSOL Multiphysics, we solved Laplace’s equation for the electric field and Pennes’ equation for the temperature distribution. To mimic the therapy as realistically as possible, we also considered complete current shutdown whenever any transducer reached 41 °C to allow transducers and tissues’ temperature to decrease. Our results indicate an intermittent operation of Optune due to this necessary current shutdown. Localized temperature increases were seen, especially underneath the regions where the transducers were placed. Maximum temperature values were around 41.5 °C on the scalp and 38 °C on the brain. According to the literature, significant thermal impact is only predicted for the brain where the rise in temperature may lead to an increased BBB permeability and variation in the blood flow and neurotransmitter concentration. Additionally, our results showed that if the injected current is reduced by around 25% compared to Optune’s standard way of operating, then uninterrupted treatment might be attainable. These predictions might be used to improve TTFields delivery in real patients and to increase awareness regarding possible thermal effects not yet reported elsewhere.
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Lin, W., E. Yeh, W. Soh, M. Kinoshita, H. Ito, and J. Hung. "A case study of determining orientations of in-situ horizontal principal stresses based on electrical images of borehole failures at a deep drilling project." In Eurock 2006: Multiphysics Coupling and Long Term Behaviour in Rock Mechanics, 625–30. Taylor & Francis, 2006. http://dx.doi.org/10.1201/9781439833469.ch91.
Full textConference papers on the topic "Multiphysic imager"
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Di Santo, Simone, Nadege Bize-Forest, Isabelle Le Nir, and Carlos Maeso. "WELLBORE IMAGES DIGITAL FUSION: BEYOND SINGLE-SENSOR PHYSICAL CONSTRAINTS." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0007.
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In the modern oilfield, borehole images can be considered as the minimally representative element of any well-planned geological model/interpretation. In the same borehole it is common to acquire multiple images using different physics and/or resolutions. The challenge for any petro-technical expert is to extract detailed information from several images simultaneously without losing the petrophysical information of the formation. This work shows an innovative approach to combine several borehole images into one new multi-dimensional fused and high-resolution image that allows, at a glance, a petrophysical and geological qualitative interpretation while maintaining quantitative measurement properties. The new image is created by applying color mathematics and advanced image fusion techniques: At the first stage low resolution LWD nuclear images are merged into one multichannel or multiphysics image that integrates all petrophysical measurement’s information of each single input image. A specific transfer function was developed, it normalizes the input measurements into color intensity that, combined into an RGB (red-green-blue) color space, is visualized as a full-color image. The strong and bilateral connection between measurements and colors enables processing that can be used to produce ad-hoc secondary images. In a second stage the multiphysics image resolution is increased by applying a specific type of image fusion: Pansharpening. The goal is to inject details and texture present in a high-resolution image into the low resolution multiphysics image without compromising the petrophysical measurements. The pansharpening algorithm was especially developed for the borehole images application and compared with other established sharpening methods. The resulting high-resolution multiphysics image integrates all input measurements in the form of RGB colors and the texture from the high-resolution image. The image fusion workflow has been tested using LWD GR, density, photo-electric factor images and a high-resolution resistivity image. Image fusion is an innovative method that extends beyond physical constraints of single sensors: the result is a unique image dataset that contains simultaneously geological and petrophysical information at the highest resolution. This work will also give examples of applications of the new fused image.
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Wu, Hao, Parth Bansal, Zheng Liu, Yumeng Li, and Pingfeng Wang. "Uncertainty Quantification on Mechanical Behavior of Corroded Plate With Statistical Shape Modeling." In ASME 2023 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/detc2023-117050.
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Abstract Corrosion is a process of uncertain nature considering the randomness associated with corrosion initiation and growth, therefore estimating the stochastic behavior of a corroded structure therefore quantifying of system performance uncertainties would be very important for a wide range of engineering systems such as the shipment structure to ensure structural safety and reliability. In the presented study, we have focused on estimating uncertainty on plate mechanical behaviors due to the impact of the corrosion, such as the shape and depth. Considering the limitation of small quantity of corroded plate samples, we firstly regenerate simulated images based on the statistical shape modeling method. Secondly, these simulated images are imported into a multiphysics-based corrosion simulation platform to reconstruct the shape of corroded plate and the mechanical behavior of the plate with different severity levels of corrosions can be obtained through finite element analysis. Thirdly, uncertainty quantification study is then conducted to understand the statistical characteristic of stochastic behavior of corroded plates from simulated and origin image data. The case study results showed that the statistical characteristic of mechnical behavior from both source data are similar, and the statistical shape modeling method could be useful in situations where there is insufficient sample data for uncertainty quantification.
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Cao, Yi, Zeyao Mo, Zhiwei Ai, Huawei Wang, and Li Xiao. "HYBRID SCHEDULING FRAMEWORK FOR PARALLEL VISUALIZATION OF LARGE-SCALE MULTIPHYSICS SIMULATION DATA." In International Conference on Computer Graphics, Visualization, Computer Vision and Image Processing 2019. IADIS Press, 2019. http://dx.doi.org/10.33965/cgv2019_201906l028.
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Ozaltun, Hakan, Herman Shen, and Pavel Medvedev. "Finite Element Simulation for Structural Response of U7Mo Dispersion Fuel Plates via Fluid-Thermal-Structural Interaction." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40759.
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This article presents numerical simulation of dispersion fuel mini plates via fluid-thermal-structural interaction performed by commercial finite element solver COMSOL Multiphysics to identify initial mechanical response under actual operating conditions. Since fuel particles are dispersed in Aluminum matrix, and temperatures during the fabrication process reach to the melting temperature of the Aluminum matrix, stress/strain characteristics of the domain cannot be reproduced by using simplified models and assumptions. Therefore, fabrication induced stresses were considered and simulated via image based modeling techniques with the consideration of the high temperature material data. In order to identify the residuals over the U7Mo particles and the Aluminum matrix, a representative SEM image was employed to construct a microstructure based thermo-elasto-plastic FE model. Once residuals and plastic strains were identified in micro-scale, solution was used as initial condition for subsequent multiphysics simulations at the continuum level. Furthermore, since solid, thermal and fluid properties are temperature dependent and temperature field is a function of the velocity field of the coolant, coupled multi-physics simulations were considered. First, velocity and pressure fields of the coolant were computed via fluid-structural interaction. Computed solution for velocity fields were used to identify the temperature distribution on the coolant and on the fuel plate via fluid-thermal interaction. Finally, temperature fields and residual stresses were used to obtain the stress field of the plates via fluid-thermal-structural interaction.
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Hosseini, Mahmoud Reza, and Nader Jalili. "Multiphysics, Multiphase Modeling of Carbon Nanotube Synthesis Process by Chemical Vapor Deposition." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-42525.
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In the present paper, a comprehensive modeling framework is proposed to conduct multiphysics, multiphase modeling of carbon nanotube (CNT) fabrication process by chemical vapor deposition (CVD). The modeling is based on fluid dynamics, heat transfer, chemical reaction, as well as mass transport phenomena which have been fully coupled with each other. The inserted gasses are considered as methane (CH4) as the main hydrocarbon gas and hydrogen (H2) as the process enhancement gas. In the gas phase reaction section, a novel set of reactions for CH4 hydrocarbon gas is proposed which is based on 71 different chemical reactions that take place near CVD inlet. Also, surface reactions are modeled by considering 19 set of reactions acting near substrate surface which lead to CNTs formation. The investigation is performed for different combination of gas flow rate quantities ranging from 500 to 1000 sccm (standard cubic centimeter per minute) for methane and 250 to 500 sccm for hydrogen gas. Also, the quartz tube temperature is considered to change from 700 to 1000 °C. Since the thermal specifications for each species are calculated individually, the gas flow inside the quartz tube is treated as nonisothermal flow. Numerous simulations are conducted and the results are compared with the fabricated CNT’s images taken by the SEM (scanning electron microscopy). Utilizing the obtained diagrams from modeling, the effects caused by gas mixture flow rate and temperature changes on the production rate of gas phase species such as H, CH3, C2H2 and bulk carbon species (C and 2C) that produced by surface species TC and TC2 are investigated. It is found that increasing the fabricated temperature causes a rise in species production rate. However, it is observed that the produced species respond differently to any change in hydrogen and hydrocarbon flow rates. The velocity, temperature profile as well as concentration distribution along the silicon substrate length have been also investigated. This study can lead to a controlled CNTs manufacturing process when combined with in-situ measurement systems.
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Dionigi, Marco, Slawomir Koziel, Mauro Mongiardo, and Renzo Perfetti. "Iterative determination of conjugate image impedances for N-port networks." In 2015 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO). IEEE, 2015. http://dx.doi.org/10.1109/nemo.2015.7415007.
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Sun, Daozhong, Yunhua Wang, Yining Bai, and Yanmin Zhang. "Ocean Waves Inversion Based on Airborne Radar Images with Small Incident Angle." In 2020 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO). IEEE, 2020. http://dx.doi.org/10.1109/nemo49486.2020.9343415.
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Chen, Hui, WenMing Yu, and TieJun Cui. "Fast ISAR Image Simulation of Targets with Rough Boundary at Terahertz Frequencies." In 2020 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO). IEEE, 2020. http://dx.doi.org/10.1109/nemo49486.2020.9343472.
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Meng, Tian Mu, and Jian Cheng Yu. "Normal PCB-based substrate integrated image guide transmission line and leaky-wave antenna." In 2016 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO). IEEE, 2016. http://dx.doi.org/10.1109/nemo.2016.7561652.
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Gao, Xiang, Jianping An, and Xiangyuan Bu. "Modeling and Simulation of an Antenna-Coupled Image-Reject High-Temperature Superconducting Terahertz Receiver." In 2020 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO). IEEE, 2020. http://dx.doi.org/10.1109/nemo49486.2020.9343410.
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