Littérature scientifique sur le sujet « Collapse de bulle »
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Articles de revues sur le sujet "Collapse de bulle"
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Desdiani Desdiani. « Multiple bullae in asthmatic patients ». International Journal of Biological and Pharmaceutical Sciences Archive 5, no 2 (30 juin 2023) : 085–88. http://dx.doi.org/10.53771/ijbpsa.2023.5.2.0053.
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Emphysema bullae are often found in patients with chronic obstructive pulmonary disease and if the size of the bulla fulfills > 30% of the hemithorax, it can be called a giant bullae. A giant bullae can be similar to a pneumothorax, requiring a CT scan of the chest to avoid misdiagnosis and unnecessary procedures. The difference between a bulla and a pneumothorax obtained from imaging results is that if the lung collapses towards the ipsilateral hilum it is called a pneumothorax, while the bulla will appear to surround or wrap around the lung. Asthma is a disease characterized by chronic inflammation and bronchoconstriction. In acute asthma attacks or exacerbations, bronchoconstriction causes severe bilateral lung parenchymal inflation.We present a case of a 32-years-old male with multiple bullae, a complete history of tuberculosis treatment and suffering from asthma since childhood but not controlled. In this case, the likelihood of Multiple bullae in asthmatic patients, needs to be a concern, as well as the importance of evaluation and strict follow-up to reduce shortness of breath and improve the patient's quality of life.
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Read, Andrew, William Parry-Jones et Angshu Bhowmik. « Percutaneous drainage of a fluid-containing emphysematous bulla ». BMJ Case Reports 14, no 5 (mai 2021) : e240914. http://dx.doi.org/10.1136/bcr-2020-240914.
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We present the case of a 38-year-old man, with congenital bullous emphysema, who presented with unilateral pleuritic chest pain, rigors and a non-productive cough. A chest X-ray on admission demonstrated extensive bilateral bullous lung disease with left-sided lung collapse. There were fluid levels present within several bullae, with the largest bulla compromising most of the posterior aspect of the left lung base. We suspected infected emphysematous bullae. Despite prolonged conservative management with antibiotics the patient deteriorated clinically, consistently spiking temperatures and desaturating. Repeat imaging demonstrated further accumulation of fluid in the largest bulla. A small bore chest drain was inserted into this bulla under ultrasound guidance, draining 550 mL of pulmonary fluid. The patient stabilised clinically and was discharged. He remained well after completing six weeks of intravenous antibiotics in the community.
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Park, Junghyun, Dulee Kim, Jae-Hoo Park, Ji-Yun Lee et Eun-Jung Cho. « Cardiovascular Collapse after the Induction of Anesthesia Due to the MASS Effect of Unruptured Giant Bullae ». Medicina 59, no 9 (20 septembre 2023) : 1689. http://dx.doi.org/10.3390/medicina59091689.
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Background and Objectives: Giant bullae rupture easily and cause tension pneumothorax, which can cause problems during general anesthesia. However, the hemodynamic instability that can occur due to the mass effect of an unruptured giant bulla should not be overlooked. Case report: A 43-year-old male patient visited the emergency room with an abdominal wound. There was a giant emphysematous bulla in the left lung. Emergency surgery was decided upon because there was active bleeding according to abdominal CT. After tracheal intubation, the patient’s blood pressure and pulse rate dramatically decreased. His blood pressure did not recover despite the use of vasopressors and discontinuation of positive pressure ventilation applied to the lungs. Thus, a bullectomy was immediately performed. The patient’s blood pressure and pulse rate were normalized after the bullectomy. Conclusions: If emergency surgery under general anesthesia is required in a patient with a giant emphysematous bulla, it is safe to minimize positive pressure ventilation and remove the giant emphysematous bulla as soon as possible before proceeding with the remainder of the surgery. Tension pneumothorax due to the rupturing of a bulla should be considered first. However, hemodynamic changes might occur due to the mass effect caused by a giant bulla.
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Korymasov, E. A., A. S. Benian, Ju V. Bogdanova, K. M. Kolmakova, M. A. Medvedchikov-Ardiia et D. Yu Konovalova. « Challenges in diagnosis and treatment of pneumothorax and giant bullae ». PULMONOLOGIYA 31, no 4 (31 juillet 2021) : 499–504. http://dx.doi.org/10.18093/0869-0189-2021-31-4-499-504.
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Spontaneous pneumothorax is the most common acute chest disease. Often, giant bullae give the impression of the presence of air in the pleural cavity. Inadequate differential diagnosis leads to vain drainage of the pleural cavity, damage to the lung with its collapse and pneumothorax.The aim. Analyze diagnostic and tactical mistakes in patients with pulmonary emphysema, which manifests with giant bullae, and outline the ways to prevent complications.Methods. The analysis of the treatment of 1,636 patients with pulmonary emphysema and its complications undergoing treatment in the thoracic surgical department of the Samara Regional Clinical Hospital named after V.D.Seredavin in the period from 2001 to 2018 is presented.Results. Giant bulla were diagnosed in 35 (2.1%) patients, 16 of them were hospitalized ungently. In 6 patients, the diagnosis of a giant bulla of the lung was correct, and the patients were referred to the thoracic surgical department. In 10 patients, a giant bulla of the lung was regarded as pneumothorax, and pleural drainage was performed before referral to the thoracic surgical department.Conclusion. The correct interpretation of the radiological data and comparison with the clinical picture allows avoiding diagnostic errors and the associated danger and complications.
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Du, Hongkai, Jiaxin Yu, Yuandong Wang, Yuhua Zhu, Yuyang Tang et Haimeng Wang. « Visualized Failure Prediction for the Masonry Great Wall ». Buildings 12, no 12 (14 décembre 2022) : 2224. http://dx.doi.org/10.3390/buildings12122224.
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The cultural, architectural, and historical heritage value of the Great Wall of China drives the need to maintain, rehabilitate, and restore its structural integrity from artificial and natural damage. In this study, a hybrid architectural visualization and structural collapse simulation of the Ming Great Wall (1368–1644 AD) are conducted in Blender based on the unit blocks and a physics engine (i.e., Bullet Constraint Builder). Visualized failure predictions caused by four damages, i.e., stone layer collapse, step collapse, parapet walls inward tilting, and stone layer bulge, are developed and performed on a strength basis. The main input parameters are brick dimensions, friction coefficient, and adhesive/glue strength, while the primary output includes collapse, and global and local stabilities. Finally, the results show that the combination of unit blocks and a physical engine can visually simulate the occurrence process of the Great Wall’s failures with preliminary engineering outcome, especially those related to collapse, and can also predict the adverse consequences of the precipitating factors.
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Haloi, Prajnananda, Rahul Biswas et Ananta K. Bora. « Anesthetic management of a case of a lip mass with paraseptal emphysema and multiple bilateral giant bullae for surgical resection under mental nerve block ». Saudi Journal of Anaesthesia 18, no 3 (4 juin 2024) : 442–44. http://dx.doi.org/10.4103/sja.sja_43_24.
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Anesthesia in patients with emphysematous giant bulla undergoing non-thoracic surgery is challenging and can cause serious complications. We report a successful case of lip mass resection in a 65-year-old male with paraseptal emphysema and giant bullae under regional anesthesia using a mental nerve block. The patient presented with a slow-growing ulcerative mass on his lower lip and had a history of non-compliant COPD management. An excisional biopsy was planned. Preoperative workup revealed extensive lung pathology with giant bullae. General anesthesia with positive pressure ventilation in patients with emphysematous giant bullae can cause compression of lung parenchyma, vena cava kinking, circulatory collapse, and even death. To circumvent such risks, regional anesthesia was preferred and surgery was successfully done under ultrasound-guided bilateral mental nerve block. The procedure was uneventful, with stable hemodynamics throughout.
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Boyd, Jeffrey. « The Quantum World Is Astonishingly Similar to Our World : The Timing of Wave Function Collapse According to The Theory of Elementary Waves ». JOURNAL OF ADVANCES IN PHYSICS 14, no 2 (3 septembre 2018) : 5598–610. http://dx.doi.org/10.24297/jap.v14i2.7555.
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This is one of a series of articles building a map of elementary waves, based on experimental data and quantum mathematics. Previous articles showed that elementary waves carry no energy. Particles follow them backwards. Why? Elementary rays consist of probability amplitudes, which influence particles because that is what probability amplitudes do. Elementary waves are that part of nature corresponding to quantum mathematics. Since these waves are the physical analogs of quantum equations, those equations provide a roadmap to the world of elementary waves: a map written in hieroglyphs. Quantum math is our Rosetta stone. The quantum world is far, far more similar to the world of everyday experience than quantum experts think. Waves are in a superposition. Particles are not. Wave function collapse does not occur when we measure something. It had occurred much earlier, when the object came into existence. This resolves insoluble problems that stumped John von Neumann. The smooth functioning of a Schrödinger equation abruptly collapses into one specific eigenstate when a gun is fired, not when the bullet hits the target. The bullet that caused World War I is an example. That bullet caused an abrupt collapse of the smooth probabilities of commerce and diplomacy.
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Shariff, Masood A., Vijay A. Singh, Edward D. Daniele, Nikhil Goyal, Deliana Peykova, John P. Nabagiez et Frank M. Rosell. « Spontaneous Collapse of Bilateral Bullae with Conservative Management ». Clinical Medicine Insights : Case Reports 6 (janvier 2013) : CCRep.S11187. http://dx.doi.org/10.4137/ccrep.s11187.
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We report a case of bilateral apical lung bullae that collapsed following an episode of community-acquired pneumonia with bilateral air fluid levels. With standard treatment for community-acquired pneumonia, management of a patient that may have qualified for bullectomy, (as in our case) showed complete resolution of all pathology without surgical intervention. Conservative management took precedence in alleviating pathology over surgical intervention.
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Jozic, Ivan, Jérémy Chéret, Beatriz Abdo Abujamra, Mariya Miteva, Jennifer Gherardini et Ralf Paus. « A Cell Membrane-Level Approach to Cicatricial Alopecia Management : Is Caveolin-1 a Viable Therapeutic Target in Frontal Fibrosing Alopecia ? » Biomedicines 9, no 5 (19 mai 2021) : 572. http://dx.doi.org/10.3390/biomedicines9050572.
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Irreversible destruction of the hair follicle (HF) in primary cicatricial alopecia and its most common variant, frontal fibrosing alopecia (FFA), results from apoptosis and pathological epithelial-mesenchymal transition (EMT) of epithelial HF stem cells (eHFSCs), in conjunction with the collapse of bulge immune privilege (IP) and interferon-gamma-mediated chronic inflammation. The scaffolding protein caveolin-1 (Cav1) is a key component of specialized cell membrane microdomains (caveolae) that regulates multiple signaling events, and even though Cav1 is most prominently expressed in the bulge area of human scalp HFs, it has not been investigated in any cicatricial alopecia context. Interestingly, in mice, Cav1 is involved in the regulation of (1) key HF IP guardians (TGF-β and α-MSH signaling), (2) IP collapse inducers/markers (IFNγ, substance P and MICA), and (3) EMT. Therefore, we hypothesize that Cav1 may be an unrecognized, important player in the pathobiology of cicatricial alopecias, and particularly, in FFA, which is currently considered as the most common type of primary lymphocytic scarring alopecia in the world. We envision that localized therapeutic inhibition of Cav1 in management of FFA (by cholesterol depleting agents, i.e., cyclodextrins/statins), could inhibit and potentially reverse bulge IP collapse and pathological EMT. Moreover, manipulation of HF Cav1 expression/localization would not only be relevant for management of cicatricial alopecia, but FFA could also serve as a model disease for elucidating the role of Cav1 in other stem cell- and/or IP collapse-related pathologies.
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Večerek, Vladimír, Eva Voslářová, Josef Kameník, Zuzana Machovcová, Lenka Válková, Martina Volfová et Jarmila Konvalinová. « The effect of slaughtering skills on the welfare of cattle during stunning with a captive bolt ». Acta Veterinaria Brno 90, no 1 (2021) : 109–16. http://dx.doi.org/10.2754/avb202190010109.
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The performance of stunning in various abattoirs can differ. The aim of the study was to compare the stunning of cattle with a captive bolt in two abattoirs. We monitored the slaughtering skills by measuring the deviation of the location of the stunning shot hole on the skull from the ideal point and further by measuring the angle of inclination of the stunning shot on the skull from the ideal perpendicular angle. We observed the impact of different slaughter skills on the quality of stunning of animals based on the occurrence of failure to achieve motor paralysis after a stun shot. The failure to collapse occurred significantly more frequently (P < 0.05) in abattoir A than in abattoir B. In both abattoirs there was a higher (P < 0.05) number of bulls failing to collapse than in females (cows and heifers). However, the effect of slaughter skills on the occurrence of signs associated with insufficient stunning was not found. The signs occurred in abattoir A and abattoir B to the same extent. In bulls, the number of animals with signs was higher (P < 0.05) than in females in both abattoirs. The results show that insufficient proficiency of skills in stunning cattle with a captive bolt leads to a higher number of animals failing to collapse after a stun shot. The effect of slaughter skills on the occurrence of signs in bulls and females was not proven; however, in bulls a higher incidence of signs was demonstrated than in females.
Thèses sur le sujet "Collapse de bulle"
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Pineda, Rondon Saira Freda. « Numerical prediction of cavitation erosion ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC031/document.
Texte intégralRésumé :
La cavitation peut avoir lieu dans les turbines hydrauliques. Ce phénomène se produit lorsque les bulles de vapeur s’effondrent à proximité de la surface de la machine. Ceci entraîne des conséquences négatives, telles que l’érosion, affectant ainsi les performances de la machine. L’effondrement d’une bulle de gaz non-condensable dans l’eau est simulé en utilisant la méthode sans maillage SPH-ALE, qui intègre un modèle pour simuler les écoulements compressibles et multiphases. Le modèle résout les équations de conservation de masse, de quantité de mouvement et d’énergie du système d’Euler, en utilisant l’équation d’état de Stiffened Gas pour l’eau et l’équation d’état de gaz parfait pour le gaz non-condensable à l´ıntérieur de la bulle. Les deux phases sont modélisées comme compressibles et le changement de phase n’est pas considéré. La caractéristique sans maillage de la méthode SPH-ALE permet le calcul des écoulements diphasiques où l’interface est nettement définie. Pour les applications de cavitation, où le nombre de Mach atteint des valeurs de 0.5, la distribution de particules doit être corrigée. Cela est réalisé grâce à la fonctionnalité ALE. Le modèle compressible a été validé à l’aide de configurations monodimensionnelles, comme le cas du tube à choc pour des écoulements monophase et multiphases. L’effondrement de la bulle près d´une paroi a été abordé comme le mécanisme fondamental qui produit des dégâts. Son comportement général se caractérise par la formation d’un micro jet d’eau et par l’effondrement de la bulle sur elle-même. Le phénomène est analysé en tenant compte des principaux paramètres qui le régissent, comme la distance initiale entre le centre de la bulle et la paroi (H0), la taille de la bulle (R0) et le taux de pression qui entraîne l’effondrement (pw/pb). Il est démontré que l’intensité de l’effondrement dépend principalement du rapport de pression entre le liquide et la bulle (pw/pb). De plus, quatre indicateurs, comme la pression en paroi, l’impulsion, la pression du coup de bélier et la vitesse du micro jet d’eau, servent à déterminer le chargement. Cette analyse indique qu’une bulle initialement située à une distance inférieure à H0/R0 = 2 présente un haut potentiel d’endommagement. Afin de prédire cet endommagement, la mécanique du solide est analysée à l’aide de simulations d’interaction fluide-structure. On obtient que le matériau réagit aux charges hydrauliques en ayant des zones de compression et de traction. Ceci suggère qu’un mécanisme de fatigue entraîne le phénomène d’endommagement. En plus, on constate que les contraintes les plus importantes sont situées sous la surface du matériau, indiquant que cette zone peut être sujette à une déformation plastiqueHydraulic turbines can experience cavitation, which is a phenomenon occurring when vapor bubbles collapse in the vicinity of the machine’s surface. This phenomenon can lead to negative consequences, such as erosion, that affect the machine’s performance. The compression of a non-condensable gas bubble in water is simulated with the Smoothed Particle Hydrodynamics method following the Arbitrary Lagrange Euler approach (SPHALE), where a compressible and multiphase model has been developed. The model solves the mass, momentum and energy conservation equations of the Euler system using the Stiffened Gas EOS for water and the ideal gas EOS for the non-condensable gas inside the bubble. Both phases are modeled as compressible and the phase change is not considered. The meshless feature of the SPH-ALE method allows the calculation of multiphase flows where the interface is sharply defined. For cavitation applications, where the Mach number reaches values of 0.5, the distribution of particles must be corrected, which is achieved by the ALE feature. The compressible model was validated through monodimensional configurations, such as shock tube test cases for monophase and multiphase flows. The bubble compression close to the wall has been addressed as the fundamental mechanism producing damage. Its general behavior is characterized by the formation of a water jet and by the collapse of the bubble by itself. The phenomenon is analyzed by considering the major parameters that govern the bubble collapse dynamics, such as the initial distance between the bubble center and the wall (H0), the bubble size (R0), and the collapse driven pressure ratio (pw/pb). It is shown that the intensity of the collapse depends mainly on the pressure ratio between the liquid and the bubble (pw/pb). As well, four indicators, such as the pressure at the wall, the impulse, the water-hammer pressure and the water jet velocity, are used to determine the loading. This analysis gives that the bubble initially located at a distance lower than H0/R0 = 2 presents high potential to cause damage. In order to predict the damage due to the bubble collapse, the solid mechanics is analyzed through fluid-structure interaction simulations. It is obtained that the material reacts to the hydraulic loads by having compression and traction zones, suggesting that a fatigue mechanism drives the damage phenomenon. Additionally, it is found that the highest stresses are located below the material surface, indicating that this zone may reach plastic deformation
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Ménez, Lucas. « Développement de méthodes des frontières immergées pour l’étude de problèmes couplés fluide-structure ». Electronic Thesis or Diss., Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2024. http://www.theses.fr/2024ESMA0025.
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L’érosion de cavitation représente un problème majeur pour les applications hydrauliques et marines. Ce phénomène est la conséquence de la superposition de pits de cavitation en surface du matériau, formés par l’implosion (ou collapse) de bulles au voisinage de la paroi. Afin d’apporter une meilleure compréhension du phénomène et des problématiques liées à sa résolution numérique, une stratégie de couplage fort entre le fluide et la structure, basée sur une approche partitionnée, a été développée. Elle est basée sur le code interne SCB (volumes finis), le solveur libre FEniCS (éléments finis) et sur la librairie de couplage preCICE. L’originalité de notre approche réside dans l’utilisation d’une méthode des frontières immergées (IBM) pour modéliser l’interface déformable, dans le but de réduire le coût de calcul par rapport à une approche classique de type maillage conforme. À l’issue d’une étude comparative de deux IBM, la méthode de pénalisation a été retenue pour sa précision et son efficacité. Elle a ensuite été étendue à un modèle diphasique à interface diffuse dans le but d’étudier la formation et l’évolution d’un écoulement cavitant puis le collapse d’une bulle au voisinage d’une paroi rigide, révélant une possible accélération de l’érosion de cavitation lorsque la paroi est déjà endommagée. Notre stratégie SCB-FEniCS-preCICE a finalement été appliquée à l’étude de la formation d’un pit de cavitation. La version originale de la méthode de pénalisation engendre une erreur de l’ordre de 30 % concernant l’endommagement du matériau. Une variante de la méthode a été imaginée afin de surmonter ce problème en contrôlant l’impédance acoustique du milieu pénalisé. Deux études paramétriques croisées ont montré que les pits les plus profonds se forment suite au collapse d’une bulle initialement très proche d’un matériau de faible limite d’élasticité. Le couplage faible surestime l’impact (20 %) et l’endommagement (50 %). L’effet du couplage est accentué localement lorsque la plasticité est plus importanteCavitation erosion is a major issue for hydraulic and marine applications. This phenomenon results from the accumulation of cavitation pits on the surface of the material, formed by the collapse of bubbles near the wall. To provide a better understanding of the phenomenon and the challenges related to its numerical resolution, a strong fluid-structure coupling strategy, based on a partitioned approach, has been developed. It is based on the in-house code SCB (Finite Volume Method), the open-source solver FEniCS (Finite Element Method), and the coupling library preCICE. The originality of our approach lies in the use of an Immersed Boundary Method (IBM) to model the deformable interface in order to reduce computational cost compared to a classical body-fitted approach. After a comparative study of two IBMs, the penalization method was chosen for its accuracy and efficiency. It was then extended to a diffuse interface two-phase flow model to study the formation and evolution of a cavitating flow, followed by the collapse of a bubble near a rigid wall, revealing a possible acceleration of cavitation erosion when the wall is already damaged. Finally, the SCB-FEniCS-preCICE strategy was applied to the study of cavitation pit formation. The original version of the penalization method generates an error of about 30 % regarding material damage. A variant of the method was developed to overcome this issue by controlling the acoustic impedance of the penalized region. Two parametric studies showed that the deepest pits form after the collapse of a bubble initially very close to a material with a low yield strength. Weak coupling overestimates impact pressure (20 %) and material damage (50 %). The effect of coupling is locally amplified when plasticity is more important
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Capuano, Marion. « Simulations numériques d'écoulements diphasiques compressibles, visqueux et conductifs à l'aide de schémas aux différences finies d'ordre élevé ». Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEC016/document.
Texte intégralRésumé :
Ce travail de thèse porte sur le simulation d’écoulements diphasiques compressibles, visqueux et conductifs, à l’aide de schémas numériques aux différences finies centrées d’ordre élevé. Pour cela, les équation utilisées sont les équations de Navier-Stokes complétées de deux équations d’advection décrivant l’interface et d’une équation permettant d’estimer la température au sein d’un liquide et d’un gaz. Elles sont résolues à l’aide de méthodes numériques conservatives précédemment développées pour l’aéroacoustique, adaptées dans la présente étude à la simulation d’écoulements diphasiques. Les choix des équations et des méthodes numériques sont validés à l’aide de divers cas test monodimensionnels proposés dans la littérature. Les résultats obtenus sont en accord avec les solutions analytiques ou de référence. Deux écoulements 2D composés de deux gaz sont ensuite considérés. Le premier cas concerne l’instabilité de Richtmyer-Meshkov qui se développe à l’interface entre de l’air et du SF6. Le second cas porte sur une bulle cylindrique remplie d’hélium ou de R22 impactée par une onde de choc plane se propageant dans l’air. Pour ces deux écoulements, une étude de convergence de maillage est effectuée et les solutions numériques sont comparables aux données expérimentales de la littérature. L’influence du nombre de Reynolds sur la déformation de l’interface de la bulle d’hélium est également montrée. Enfin, l’implosion d’une bulle d’air dans l’eau est étudiée. Dans un premier temps, l’implosion sphérique de la bulle suite à son interaction avec une onde de pression convergente est simulée. Les résultats sont en bon accord avec les solutions prédites par le modèle de Rayleigh-Plesset. L’influence de l’épaisseur initiale de l’interface et de la conductivité thermique est montrée. Dans un second temps, l’implosion non sphérique d’une bulle proche d’un mur et impactée par une onde de choc plane est considérée. La pression imposée sur le mur et la température au sein de l’écoulement sont quantifiées. Enfin, une étude de l’effet de la distance initiale entre le mur et la bulle sur l’implosion est menéeThis PhD work concerns the simulation of compressible, viscous and conductive two-phase flows, using high-order centered finite-difference schemes. The equations governing two-phase flows are the Navier-Stokes equations in conjunction with two advection equations governing the interface and one equation allowing to estimate the temperature within a liquid and a gas. These are solved using conservative numerical methods which are validated from the resolution of various 1D test cases taken from the literature. The results obtained are in good agreement with the analytical or reference solutions. Then, two 2-D flows composed of two gases are considered. The first case concerns the Richtmyer-Meshkov instability developping at the interface between air and SF6. The second case deals with a cylindrical bubble filled with helium or R22 which is hit by a plane shock wave travelling through air. For these two flows, a grid convergence study is conducted and the numerical solutions compare well with the experimental data of the literature. The effect of the Reynolds number on the deformation of the bubble interface is also shown. Finally, the collpase of an air bubble in water is studied. Firstly, the spherical collapse of the bubble due to its interaction with a spherical converging shock wave is simulated. The results are in good agreement with the solutions predicted by the Rayleigh-Plesset model. The effect of the initial interface thickness and the thermal conductivity on the collapse is investigated. Secondly, the non-spherical collapse of a bubble near a wall impacted by a plane shock wave is considered. The pressure imposed on the wall and the temperature within the flow are quantified. Finally, the influence of the initial stand-off distance between the wall and the bubble is examined
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Daou, Maya Mounir. « Investigation of the plate-impact method as a precursor of physical phenomena and chemical processes ». Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066245/document.
Texte intégralRésumé :
Ce manuscrit a pour but d'étudier un nouveau dispositif générateur de cavitation dont le potentiel favorable à l'intensification de réactions chimiques est évalué. Ce dispositif est constitué d'une plaque mobile qui frappe un liquide contenu dans un réacteur. L'impact génère une forte augmentation de pression dans le milieu suivi d'une dépressurisation. Nous montrons que la couche de gaz/vapeur piégée entre le piston et la surface du liquide influence les pics de pression et les fréquences générées dans le milieu. La visualisation à l'aide d'une caméra rapide montre que la dépressurisation active les sites de nucléation à l'origine des bulles de cavitation qui grandissent et implosent en générant occasionnellement des jets de grande vitesse. Nous étudions aussi la réponse de bulles préexistantes. Nous identifions un rayon de bulle critique qui dépend de la hauteur d'impact, de la pression extérieure et des caractéristiques du piston. Les bulles dont le rayon initial est supérieur à la valeur critique implosent au moment de l'impact, tandis que les petites bulles ne sont activées qu'après (sous tension). Des évolutions de pression différentes sont observées après l'impact en fonction de la présence/absence de grandes bulles. Nous étudions enfin l'oxydation du phénol en montrant que l'impact sur l'eau pure est incapable de générer des espèces radicalaires responsables de la dégradation. En ajoutant du peroxyde d'hydrogène comme oxydant, la molécule est décomposée sous certaines conditions. En général, la quantité d'oxydant requise pour déclencher une oxydation significative diminue lors de l'augmentation de l'intensité de l'impact sur lequel dépend le taux de dégradationThis manuscript aims at characterizing a new device based on a plate impact on a liquid surface to generate cavitation and evaluate its potential to induce chemical reactions. The device is composed of a reactor containing a liquid that a piston hits due to pressure difference. This impact generates a strong and uniform pressure increase in the medium followed by a depressurization. We show that the gas/vapor layer trapped between the piston and the liquid free surface influences the pressure peaks and frequencies generated in the medium. High-speed camera visualization shows that depressurization activates nucleation sites leading to bubble appearance in the solution. Bubbles expand and collapse intensively generating high velocity jets under some conditions. We also investigate the response of pre-existing bubbles. We identify a critical bubble radius that depends on the impact height, external pressure and piston’s characteristics. Bubbles with an initial radius larger than the critical one collapse at the moment of impact while smaller bubbles are only activated after it (under tension). Significant differences are observed in the pressure recordings after the impact depending on the presence/absence of large bubbles. We finally study the oxidation of phenol. We show that impacting on pure water is incapable of generating radical species responsible of the degradation. By adding hydrogen peroxide as an oxidant we show that the molecule is decomposed under certain conditions. In general, the amount of hydrogen peroxide required to initiate a significant oxidation decreases when increasing the intensity of the impact on which the degradation rate mainly depends
Livres sur le sujet "Collapse de bulle"
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Art, SeaShell SeaShell. Notebook : Aesthetic Print Cover Lined Paper Minimal Journal Notebook : 6x9 Inches 110 Pages, Collage, Bullet, Daily Modern Notebook. Independently Published, 2021.
Trouver le texte intégralChapitres de livres sur le sujet "Collapse de bulle"
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Gilpin, Robert. « The Global Political System ». Dans Order and Violence, 112–39. Oxford University PressOxford, 1990. http://dx.doi.org/10.1093/oso/9780198275558.003.0006.
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Abstract Hedley bull was the most distinguished scholar of his generation to analyse and explore the uniqueness and genius of the modern European political order. In The Anarchical Society (1977), the subtitle of which is A Study of Order in World Politics, Bull carried forward a tradition of speculation and theorizing that extends from Hugo Grotius to Ludwig van Ranke to Bull’s own mentor, Martin Wight. Bull, however, in his last major contribution to scholarship, went beyond the themes of these earlier writings and enquired whether the European experience of statecraft has any relevance for the emergent pluralistic international system composed of diverse civilizations with vastly different conceptions of international relations. The seminal volume The Expansion of International Society (1984), edited by Bull and his colleague Adam Watson, was one of the first systematic attempts to explore this important issue. In the 1970s, when non-Western societies commenced their concerted effort for a new international economic and political order, Bull, Watson, and their collaborators addressed the question of the nature of the new international order: will it be based on the norms and precepts of the European ‘society of states’; or will ‘a new genuinely universal, and non-hegemonial structure of international relations’ replace the once dominant European system of rules and institutions; or, as at least one contributor suggested, will the collapse of the European conception of an international order give rise to ‘a new international disorder’? While the answer to these questions must await the test of time, the questions themselves are important for the scholar and for mankind in the closing decade of this century.
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Coffee, John C. « Explaining Gatekeeper Failure ». Dans Gatekeepers : The Professions and Corporate Governance, 55–77. Oxford University PressOxford, 2006. http://dx.doi.org/10.1093/oso/9780199288090.003.0007.
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Abstract Although the collapse of Enron and WorldCom make fascinating stories, they are, by themselves, just anecdotes. Alone, they are simply additional chapters in the long and spectacular history of business failure in the United States. Yet, Enron and WorldCom do not stand alone; rather, they were the best-known examples in a sudden and massive eruption of Wnancial irregularity that occurred at the end of the longest sustained bull market in U.S. history. Some firms failed, but more simply acknowledged the inflation of their Wnancial results and then endured the painful process of stock market decline, managerial transition, and public and private litigation that follows once shareholders learn they have been misled.
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McAuley, Louis Kirk. « The Poetics of Biological Invasion and Crop Monoculture in Early Caribbean Literature ». Dans The Ecology of British and American Empire Writing, 1704-1894, 110–57. Edinburgh University Press, 2024. http://dx.doi.org/10.3366/edinburgh/9781399527149.003.0003.
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Chapter 2 takes the world-ecological significance of the sugar revolution into account, in part through close analysis of both the real and imaginative confusion of Old and New World species in various forms of West Indian empire writing. This chapter considers the ways in which early Caribbean authors broadly conceive of the sugar revolution and, by extension, human history, as co-produced by manifold species. That is, this chapter explores the world-ecological orientation of Caribbean-based authors, including James Grainger, whose efforts to perfect the cultivation and processing of sugar cane led him to make some very bold suggestions concerning the vulnerability of island ecosystems to invasive species, and John Singleton, whose poem, A General Description of the West-Indian Islands (1767), portrays (in sublime detail) Caribbean nature as exhausted by intensive crop monoculture. On one hand, The Sugar-Cane (1764) merits consideration as a form of biopiracy, in keeping with Vandana Shiva’s work tracing the effects of the Papal “Bull of Donation” upon Europeans’ transoceanic plunder of nature and knowledge. On the other hand, Singleton’s poem contains contrasting passages of considerable alarm, an “aesthetic of degradation,” as it were, linking the plantation economy to ecological collapse.
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Reddy, Bhavanam Sudhakara, Kambala Swetha et Sirigireddy Sivajothi. « Otitis Interna and its Clinical Management ». Dans Common Ear Diseases in Dogs : Diagnosis and Management, 207–24. BENTHAM SCIENCE PUBLISHERS, 2025. https://doi.org/10.2174/9789815313598125010018.
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Otitis interna define as inflammation of inner ear, which will be an extension of infection from the otitis media or secondary to the chronic otitis externa. Improperly treated / untreated cases of otitis media can lead to development of otitis interna by involving the tympanic membrane. Clinical signs in otitis interna were impairment of hearing apparatus i.e. deafness and neurological indications such as tilting of the head towards the based on the side of the ear affected, development of the horizontal or rotary nystagmus, unequal legs coordination with diffused strength, circular walking pattern, sudden collapse, and even rolling towards the impacted side. Complication of otitis interna leads to development of life-threatening iotrogenic intracranial infections and meningitis by travelling the infectious organisms to the brainstem. In dogs with severe otitis interna that progressed to an intracranial infection, changes in mentation, ataxic changes, paresis, proprioceptive deficits, and development of seizures. Diagnosis of the otitis interna achieved by detailed history; dermatological, neurological and systemic examination along with the identification of underlying and/or associated factors. Otoscopic examination, cytology, microbial culture, antibiotic sensitivity test, radiography, computerized tomography scan evaluation and magnetic resonance imaging are helpful to differentiate the extent of lesions and severity. Medical management of otitis interna is carried out by identifying the suitable antibiotic by antibiotic sensitivity test followed by the correct dosage and duration approximately ranging from 4 to 8 weeks along with the systemic corticosteroids which have been advised to reduce the stenosis. When there is rupture of tympanic membrane, cautious utilization of topical antibiotic and/or anti-inflammatory preparations are advisable. If medical management fails to respond, surgical intervention are advised with vertical ear canal ablation, lateral ear canal resection, total ear canal ablation with lateral bulla osteotomy.
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Teige, Ola. « Norske provinsmatadorer : familien Adeler og makten i Kragerø ca. 1620–1760 ». Dans Hvem styrte byene ? Nordisk byhistorie 1500–1800, 245–72. Cappelen Damm Akademisk/NOASP, 2022. http://dx.doi.org/10.23865/noasp.149.ch9.
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Norwegian provincial matadors. The Adeler family and the power in the town Kragerø c. 1620–1760 This chapter describes the Norwegian coastal town of Kragerø and the position of the Adeler family in its political, social and commercial life in the period 1620–1760. It illustrates how local elite families exercised power in such towns in the early modern period, the strategies they used, and the sources of this power. In this regard, Kragerø is close to an ideal example of a town controlled by just one or a few mighty families. For 35 years, it was ruled by a single, undisputed “matador” and for the following 65 years by a small local elite. In the early 17th century, Kragerø developed as a shipping port for timber products from nearby sawmills. The Adeler family established themselves as sawmill owners, helped by their ties to noble county governors. The first known family member, Søren Jensen, came to the area as a servant to one of these governors. His son, Niels Adeler, inherited his father’s business and expanded it by aggressively acquiring local sawmills, forest properties and shipping businesses. This was fueled by massive lending. Adeler played a leading role when the local merchants successfully petitioned the Danish-Norwegian king to grant the port town rights in 1666. Adeler was then appointed mayor. He was both a royal official and a merchant, and in the 1670s and 80s his family controlled three-quarters of the local trade economy, i.e., ships, import of goods, and sawmills with export quotas. He also controlled the other town offices by using his network and influence with the king to install clients in them. The only power base he did not control was the land the town was built on, which was leased to the houseowners. In similar towns, this asset provided the owners with considerable influence locally. In 1675, Niels Adeler advanced to the post of county governor, while one of his sons inherited the mayoralty. His business expansion led to substantial debt, but he managed to avoid bankruptcy. However, after his death in 1694, his business empire collapsed, leaving nothing to his many children. This chapter documents how two of his sons reacted to the loss of wealth and power with anger and violent attempts to bully the town bailiff into letting them keep their father’s properties. A sister, Anna Adeler Poulsen, married a merchant and stayed on. They built a trading house and became one of the 4–5 elite families who dominated the town. The Adeler Poulsen family lost its position when Anna’s grandsons sold the remaining properties after 1760.
Actes de conférences sur le sujet "Collapse de bulle"
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Leblond, H., I. V. Mel’nikov et D. Mihalache. « Few-Cycle Optical Solitons in Nonlinear Media : Spatiotemporal Collapse vs Bullet Cast ». Dans Nonlinear Optics. Washington, D.C. : OSA, 2013. http://dx.doi.org/10.1364/nlo.2013.nw4a.12.
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Qu, Zhaoyu, Ning Gan, Yingyu Chen et Nana Yang. « Experimental Study on Cavitation Motion of Underwater Vehicle With Protrusions ». Dans ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18699.
Texte intégralRésumé :
Abstract For underwater vehicles with protrusions (external structure), the geometric shape of the protrusions is bound to affect the local flow field of the vehicles during the moving process of the vehicles, thus affecting the generation, development and collapse of cavitation around the vehicles. The cavitation may break, fall off and collapse randomly, and other local movements may affect the motion attitude of the underwater vehicle. It is an effective method to study fluid dynamics to simulate prototype cases with small scale models. In this paper, we mainly use the small scale model test method to explore the cavitation motion characteristics of the vehicle in water with protrusions. Through the establishment of a set of vehicle motion test equipment under reduced pressure, a series of experiments were conducted on this basis to explore the motion characteristics of vehicle cavitation under different bump shapes. In this study, two high-speed cameras were used to simultaneously record cavitation generation, development, collapse and other characteristics, to analyze the bubble generation mechanism and scale characteristics caused by the bulge, and then to study the influence of cavitation induced by the bulge on the motion attitude of the vehicle.
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Rauffus, René Bettencourt, António Maximiano, Luís Eça et Guilherme Vaz. « CFD Analysis of a Captive Bullet Entry in Calm Water With and Without Turbulence ». Dans ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/omae2019-96099.
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Abstract Simulations are carried out for a simplified lifeboat drop test case, which consists of a captive axisymmetric generic lifeboat shape (bullet), that penetrates the water surface at a constant velocity and angle of attack. The quantities of interest are the body fixed longitudinal force FX, vertical force FZ, and pitch moment MYY.This case was previously used in a verification and validation exercise [1]. Here, a step forward in complexity is taken, as the previous numerical model is now supplemented with the eddy-viscosity based turbulence model k–ω SST. Both approaches are then used to simulate two different cases: Case 1 with minimal wake effects; and Case 3 with flow separation and significant wake. The results are compared with the experimental data. The numerical uncertainty is estimated for both models. It is seen that for Case 1 the difference between both models is mostly within the comparison uncertainty, except for the longitudinal force FX, where the turbulent flow predicts a larger force, improving the comparison with the experiments. The loads predicted with turbulent flow stayed mostly within 6 % of the laminar flow. For Case 3 small differences between both models are found during/after the wake collapse stage. However, this difference is often within the comparison uncertainty. A reasonable agreement is found with the experimental data, except for FZ after the bow wake collapse. The turbulent flow improves slightly on the laminar approach regarding the agreement with the experiments, however it can be argued if this difference justifies the increased computational cost of the turbulence model.
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Limam, A., L. H. Lee, E. Corona et S. Kyriakides. « Plastic Buckling and Collapse of Tubes Under Bending and Internal Pressure ». Dans ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57986.
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This paper presents results from a recent combined experimental-analytical study of the inelastic response and the sequence of events that lead to collapse of pipes bent under internal pressure. Experimental results from stainless steel 321 seamless tubes with D/t of 52 are reported. The tubes were loaded by pure bending at fixed values of pressure ranging from zero to a value that corresponds to 0.75 times the yield pressure. The moment-curvature response is governed by the inelastic characteristics of the material. Bending induces some ovalization to the tube cross section while, simultaneously, the internal pressure causes the circumference to grow. Following some inelastic deformation, small amplitude axial wrinkles appear on the compressed side of the tube, and their amplitude grows stably as bending progresses. Eventually, wrinkling localizes, causing catastrophic failure in the form of an outward bulge. Pressure increases the wavelength of the wrinkles as well as the curvature at collapse. The onset of wrinkling is established by a custom bifurcation buckling formulation. The evolution of wrinkling and its eventual localization are simulated using a FE shell model. The material is represented as an anisotropic elastic-plastic solid using the flow theory, while the models are assigned initial geometric imperfections that correspond to the wrinkling bifurcation mode. It will be shown that all aspects of the observed behavior including the failure by localized bulging can be successful reproduced by the models developed.
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Cable, Travis A., Luis San Andrés et Karl Wygant. « On the Predicted Effect of Angular Misalignment on the Performance of Oil Lubricated Thrust Collars in Integrally Geared Compressors ». Dans ASME Turbo Expo 2016 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57888.
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Multiple-stage integrally geared compressors (IGCs) offer improved thermal efficiency and easier access for maintenance and overhaul than single-shaft centrifugal compressors. In an IGC, a main bull shaft drives pinion shafts, each having an impeller at its ends. The compression of process gas in the compressor stages induces axial loads along the pinion shafts that are transmitted via thrust collars (TCs) to the main bull gear (BG) shaft and balanced by a single thrust bearing. Manufacturing inaccuracies and a poor assembly process can lead to static angular misalignments of the TC and BG surfaces that affect the operating film thickness as well as the force and reaction moments of the lubricated mechanical element. In a follow up to Ref. [1], this paper presents an investigation of the performance of a single thrust collar configuration operating with increasing static angular misalignment of either the TC or BG. The flow model solves the Reynolds equation of hydrodynamic lubrication coupled to a thermal energy transport equation to determine the film pressure and bulk temperature fields, respectively. The model predicts performance parameters such as power loss and lubricant flow rate, and force and moment stiffness and damping coefficients. Predictions show that misaligning of either the thrust collar or bull gear alters the load carrying area in the lubricated zone, shifts the pressure field with peak magnitudes doubling or more depending on the degree and direction of TC or BG misalignment. Static angular misalignment does not significantly affect the power loss, temperature rise, etc., but does have an effect on the dynamic coefficients (both axial and angular). Finally, a reduced complex dynamic stiffness matrix for the lubricated TC shows that some cross coupled stiffness and moment coefficients are nonzero, indicating hydrodynamic coupling between axial and angular motions for the pinion and bull gear shafts. The coupling could affect the placement of the system natural frequencies and associated mode shapes as well as the system stability.
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San Andrés, Luis, Travis A. Cable, Karl Wygant et Andron Morton. « On the Predicted Performance of Oil Lubricated Thrust Collars in Integrally Geared Compressors ». Dans ASME Turbo Expo 2014 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-25914.
Texte intégralRésumé :
Integrally geared compressors (IGCs) comprise of single stage impellers installed on the ends of pinion shafts, all driven by a main bull gear (BG) and shaft system. When compared to single shaft multistage centrifugal compressors, the benefits of IGCs include better thermal efficiency, reduced footprint and simple foundation, dispensing with a high speed coupling, as well as better access for maintenance and overhauls. In IGCs the compression of the process gas induces axial loads on the pinion shafts that are transmitted via thrust collars (TCs) to the main drive shaft and balanced by a single thrust bearing. The TCs, located on either side of pinion gears, slightly overlap with the BG outer diameter to form lentil-shaped lubricant-wetted regions. Archival literature on the design and optimization of TCs is scant, in spite of their widespread usage as they are comprised of simple geometry mechanical elements. This paper presents an analysis of the hydrodynamic film pressure generated in a lubricated TC due to the rotation of both thrust collar and bull gears and specified taper angles for both bodies. The model solves the Reynolds equation of hydrodynamic lubrication to predict the operating film thickness that generates a pressure field reacting to impellers’ thrust loads; these forces being a function of the pinion speed and the process gas physical properties. The model also predicts performance parameters such as power loss and axial stiffness and damping force coefficients. A parametric study brings out the taper angles in the TC and BG that balance the transmitted load with a lesser friction factor and peak pressure, along with large axial stiffness and damping.
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Chen, Yijiang, et Javid Atai. « Dark Optical Bullets in Light Self Trapping ». Dans Nonlinear Guided Waves and Their Applications. Washington, D.C. : Optica Publishing Group, 1995. http://dx.doi.org/10.1364/nlgw.1995.nfa8.
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Propagation of a light beam in a nonlinear medium has been a subject of great interest over the last three decades. In a uniform medium, the nonlinearity has been shown to have such an effect to offset the diffraction of a beam, leading to the stationary propagation of a CW wave.1-6 In an optical fiber where a light beam is bounded by the linear guiding structure, the nonlinearity can produce a balancing effect to the dispersion of a pulsed beam to yield the stationary propagation of the pulse.7,8 In most experimental situations of light self trapping, pulsed lasers are used as sources for excitation, especially when high power operation is involved.9-11 In these circumstances, a beam of light will experience both diffraction and dispersion in addition to self-focusing (defocusing) and self phase modulation that result from nonlinearity. In a self-focusing uniform medium, it has been shown that the nonlinearity can compensate for both the diffraction and anomalous dispersion simultaneously to result in stationary propagation of the bright pulsed self-trapped beams (light bullets that evolve without change in space and time).12 In the Kerr-law medium, this stationary state of light bullets is unstable. A perturbation will lead to collapse of the light bullet.12 Nevertheless, in a saturable nonlinear medium the collapse can be bounded and the bounding may lead to the formation of stable, nondiffracting and nondispersing bright pulses.12
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Yuen, Simon, A. Boyd McKay, Daniel McArthur, Henry Kwok, John Fernando et Leanne Wong. « Local Post Weld Heat Treatment of a Pressure Vessel : A Postmortem Evaluation ». Dans ASME 2023 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/pvp2023-106971.
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Abstract This study is a postmortem evaluation of a process tower that suffered significant distortion after a local post weld heat treatment (PWHT). After installation of new nozzles near the base of the pressure vessel, heat treatment was performed to alleviate welding residual stresses in-situ, using a bulls-eye heating coil configuration. Currently, there are established industry guidelines on the placement of heating coils and insulation, but no standard analytical technique or engineering protocol or acceptance criteria that to assess a PWHT. As such, in addition to the postmortem analysis of the excessive deformation, several analytical techniques are also tested in the current study using Finite Element Analysis (FEA) to determine which method best predicts the deformation experienced by the pressure vessel in question. In these case studies, the analytical techniques include lower-bound estimate of collapse loads, buckling evaluation using linear elastic material properties, and an elastic check using a criterion provided in WRC 452. Creep elongation prediction during the short-term post weld heat treatment and buckling evaluation methods recommended by API 579-1/ASME FFS-1 are also included. The paper summarizes the findings based on the aforementioned methods, and an additional suggestion is provided related to the potential optimization of PWHT design/execution.
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Farnetano, Ruben P., Ahmed M. Daoud, Kristian Mogensen, Ahmed Fawzy, Eiman Alnuaimi et Bothainah Al Sereidi. « Novel Completion and Stimulation Technologies from Planning to Execution Tripled the Injectivity Index for the First Water Injectors in a Giant Tight Carbonate Reservoir, Onshore Abu Dhabi ». Dans SPE Reservoir Characterisation and Simulation Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/212637-ms.
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Abstract Unit R is a tight carbonate reservoir onshore Abu Dhabi currently undergoing redevelopment with the aim to substantially improve the ultimate recovery factor. Better pressure support is required to increase the production. To this end, two water injectors were drilled in tight areas where wells suffer from low injectivity index and high well head injection pressure (WHIP). Reaching the expected injection rates therefore required very aggressive matrix-acid stimulation techniques. Acid wash is a common stimulation practice for medium-high permeability wells in ADNOC when the purpose is merely to remove drilling damage without creating large negative skins. For low permeability reservoirs such as Unit R, more aggressive stimulation techniques are needed to deliver the expected production and injection target rates. We tested two such methods; Well A1 was treated using Abrasive Jetting (JA), which is conveyed by coiled tubing whereas in Well A2, we deployed a Smart Liner (SL) where acid can be bullheaded at high rate from surface. In Well A1, the Abrasive Jet CTU in Open Hole doubled the injectivity index. However, the Injection Logging Test (ILT) revealed an uneven injection profile along the horizontal section (more injection in the better properties zone). In well A2, Smart Liner bull-head acid stimulation was able to triple the injectivity index. The ILT shown an even injection profile across the horizontal section, actually slightly more in areas with poor rock properties due to a large number of holes in those intervals. The cost of the Abrasive Jet is 40% less than the Smart Liner stimulation but the latter has more medium/long term advantages: Even injection along horizontal section (improving sweep efficiency) Ensure 100% accessibility to the well (avoiding formation collapse issue) Stimulation from surface, no need CTU (saving cost), useful for potential future re-stimulations. After only 10 months of injection the reservoir pressure has increased 50-100 psi in surrounding nearby oil producers, resulting in 20% more oil while honoring all operational guidelines. It is quite exceptional to be able to assess with real data the effectiveness of two different stimulation techniques. The two pilot wells have same horizontal length, almost same rock properties, and are drilled parallel to each other. Both Smart Liner and abrasive jetting substantially improve water injectivity but the more uniform flow profile observed in the Smart Liner is a distinct advantage when selecting an appropriate completion-stimulation design for future water injectors.
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Paulo, Avner, Carlos Eduardo Oliveira De Souza, Bruna Guimarães Lima e Silva, Flávio Luiz Schiavoni et Adilson Siqueira. « Black Lives Matter ». Dans Simpósio Brasileiro de Computação Musical. Sociedade Brasileira de Computação - SBC, 2019. http://dx.doi.org/10.5753/sbcm.2019.10459.
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The Brazilian police killed 16 people per day in 2017 and 3/4 of the victims were black people. Recently, a Brazilian called Evaldo Rosa dos Santos, father, worker, musician, and black, was killed in Rio de Janeiro with 80 rifle bullets shot by the police. Everyday, the statistics and the news show that the police uses more force when dealing with black people and it seems obvious that, in Brazil, the state bullet uses to find a black skin to rest. Unfortunately, the brutal force and violence by the state and the police to black people is not a problem only in this country. It is a global reality that led to the creation of an international movement called Black Lives Matter (BLM), a movement against all types of racism towards the black people specially by the police and the state. The BLM movement also aims to connect black people of the entire world against the violence and for justice. In our work, we try to establish a link between the reality of black people in Brazil with the culture of black people around the world, connecting people and artists to perform a tribute to the black lives harved by the state force. For this, the piece uses web content, news, pictures, YouTube’s videos, and more, to create a collage of visual and musical environment merged with expressive movements of a dance, combining technology and gestures. Black culture beyond violence because we believe that black lives matter. such as the Ku Klux Klan, which bring the black population of the world into concern for possible setbacks in their rights. In Brazil, it is not different. Brazil is the non African country with the biggest afro descendant population in the world and one of the last country in the world to abolish slavery. Nowadays, a black person is 3 times more propense to be killed and most part of the murders in the country happened to afro Brazilians. Marielle Franco, a black city councillor from Rio, the only black female representative and one of seven women on the 51-seat council was killed in 2018. The killers were two former policeman. According to Human Rights Watch, the police force in the state of Rio de Janeiro, Brazil, killed more than 8,000 people between 2005 and 2015, 3/4 of them were black men. At the same time, the African culture strongly influenced the Brazilian culture and most part of the traditional Brazilian music and rhythms can be considered black music.