Academic literature on the topic 'Lagrangian point'

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Journal articles on the topic "Lagrangian point"

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Naz, R., I. Naeem, and F. M. Mahomed. "First Integrals for Two Linearly Coupled Nonlinear Duffing Oscillators." Mathematical Problems in Engineering 2011 (2011): 1–14. http://dx.doi.org/10.1155/2011/831647.

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We investigate Noether and partial Noether operators of point type corresponding to a Lagrangian and a partial Lagrangian for a system of two linearly coupled nonlinear Duffing oscillators. Then, the first integrals with respect to Noether and partial Noether operators of point type are obtained explicitly by utilizing Noether and partial Noether theorems for the system under consideration. Moreover, if the partial Euler-Lagrange equations are independent of derivatives, then the partial Noether operators become Noether point symmetry generators for such equations. The difference arises in the
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ZHANG, LI-WEI, YONG-HONG REN, YUE WU, and XIAN-TAO XIAO. "A CLASS OF NONLINEAR LAGRANGIANS: THEORY AND ALGORITHM." Asia-Pacific Journal of Operational Research 25, no. 03 (2008): 327–71. http://dx.doi.org/10.1142/s021759590800178x.

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This paper establishes a theory framework of a class of nonlinear Lagrangians for solving nonlinear programming problems with inequality constraints. A set of conditions are proposed to guarantee the convergence of nonlinear Lagrangian algorithms, to analyze condition numbers of nonlinear Lagrangian Hessians as well as to develop the dual approaches. These conditions are satisfied by well-known nonlinear Lagrangians appearing in literature. The convergence theorem shows that the dual algorithm based on any nonlinear Lagrangian in the class is locally convergent when the penalty parameter is le
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Hofer, Helmut. "Lagrangian embeddings and critical point theory." Annales de l'Institut Henri Poincare (C) Non Linear Analysis 2, no. 6 (1985): 407–62. http://dx.doi.org/10.1016/s0294-1449(16)30394-8.

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Féjoz, Jacques, Andreas Knauf, and Richard Montgomery. "Lagrangian relations and linear point billiards." Nonlinearity 30, no. 4 (2017): 1326–55. http://dx.doi.org/10.1088/1361-6544/aa5b26.

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Albert, H. F. "Point Symmetries for Lagrangian Fluid Dynamics." ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 77, no. 12 (1997): 955–58. http://dx.doi.org/10.1002/zamm.19970771217.

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Aguirre, M., and J. Krause. "Point symmetry group of the Lagrangian." International Journal of Theoretical Physics 30, no. 11 (1991): 1461–72. http://dx.doi.org/10.1007/bf00675611.

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Campoamor-Stursberg, Rutwig. "FUNCTIONAL REALIZATIONS OF LIE ALGEBRAS AS NOETHER POINT SYMMETRIES OF SYSTEMS." Acta Polytechnica 57, no. 6 (2017): 373. http://dx.doi.org/10.14311/ap.2017.57.0373.

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<p>Functional realizations of Lie algebras are applied to the problem of determining Lie and Noether point symmetries of Lagrangian systems in <em>N</em> dimensions, particularly in the plane. This encompasses both the case of symmetry-preserving perturbations of a given system, as well as the generic analysis on the structure of (regular) Lagrangians in order to admit a symmetry algebra belonging to a specific isomorphy class.</p>
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Paliathanasis, Andronikos, and Michael Tsamparlis. "The geometric origin of Lie point symmetries of the Schrödinger and the Klein–Gordon equations." International Journal of Geometric Methods in Modern Physics 11, no. 04 (2014): 1450037. http://dx.doi.org/10.1142/s0219887814500376.

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We determine the Lie point symmetries of the Schrödinger and the Klein–Gordon equations in a general Riemannian space. It is shown that these symmetries are related with the homothetic and the conformal algebra of the metric of the space, respectively. We consider the kinematic metric defined by the classical Lagrangian and show how the Lie point symmetries of the Schrödinger equation and the Klein–Gordon equation are related with the Noether point symmetries of this Lagrangian. The general results are applied to two practical problems: (a) The classification of all two- and three-dimensional
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Bolton, J., C. Rodriguez Montealegre, and L. Vrancken. "Characterizing warped-product Lagrangian immersions in complex projective space." Proceedings of the Edinburgh Mathematical Society 52, no. 2 (2009): 273–86. http://dx.doi.org/10.1017/s0013091507000922.

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AbstractStarting from two Lagrangian immersions and a horizontal curve in S3(1), it is possible to construct a new Lagrangian immersion, which we call a warped-product Lagrangian immersion. In this paper, we find two characterizations of warped-product Lagrangian immersions. We also investigate Lagrangian submanifolds which attain at every point equality in the improved version of Chen's inequality for Lagrangian submanifolds of ℂPn(4) as discovered by Opreaffi We show that, for n≥4, an n-dimensional Lagrangian submanifold in ℂPn(4) for which equality is attained at all points is necessarily m
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PLYUSHCHAY, M. S. "MASSIVE RELATIVISTIC POINT PARTICLE WITH RIGIDITY." International Journal of Modern Physics A 04, no. 15 (1989): 3851–65. http://dx.doi.org/10.1142/s0217751x89001564.

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The model of relativistic point particle, whose Lagrangian contains a linear dependence on the curvature of the particle world trajectory, is studied. The restriction on the admissible range of parameter α, standing as multiplier α−1 in the Lagrangian term with curvature, is shown to arise in the theory. The general solution of the equations of motion and quantum theory of the system are constructed in the sector with time-like vector of energy-momentum.
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Dissertations / Theses on the topic "Lagrangian point"

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Mitra, Subhadeep. "Particle filtering with Lagrangian data in a point vortex model." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/72873.

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Thesis (S.M.)--Massachusetts Institute of Technology, Computation for Design and Optimization Program, 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 131-138).<br>Particle filtering is a technique used for state estimation from noisy measurements. In fluid dynamics, a popular problem called Lagrangian data assimilation (LaDA) uses Lagrangian measurements in the form of tracer positions to learn about the changing flow field. Particle filtering can be applied to LaDA to track the flow field over a period of time. As opposed to techniques like Extended
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McCaine, Gina. "Halo orbit design and optimization." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FMcCaine.pdf.

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Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, March 2004.<br>Thesis advisor(s): I. Michael Ross, Don Danielson. Includes bibliographical references (p. 39-40). Also available online.
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Wong, Brian 1978. "Dynamics of a multi-tethered satellite system near the sun-earth Lagrangian point." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80151.

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This paper examines the dynamics of a tether connected multi-spacecraft system, arranged in a wheel-spoke configuration, in the vicinity of the L 2 Lagrangian point of the Sun-Earth system. First, the equations of motion of a N-body system are obtained and equilibrium configurations of the system are determined and small motions about one of these configurations are analyzed. Then, a numerical analysis of the free tether libration is carried out for a three-mass case when the system is near L2 and the parent mass is assumed to be in a halo orbit of different sizes. Finally, a set of con
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García, de Herreros Miciano María. "Feasibility study of the implementation of a space sunshade near the first Lagrangian point." Thesis, KTH, Rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280140.

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The lack of strong measures to avoid the possible fatal consequences of global warming is pushing researchers to look for other alternatives such as geoengineering.Within geoengineering, this study focuses on the space based solar radiation management methods. More precisely, the project evaluates the feasibilityof implementing a space sun shade near the first Lagrangian point in the Sun-Earth system within a thirty year period time from now. The study isstructured in three main blocks: spacecraft configuration, trajectory definition and launch. An analysis looking at the minimum cost system w
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Hosein, Falahaty. "Enhanced fully-Lagrangian particle methods for non-linear interaction between incompressible fluid and structure." Kyoto University, 2018. http://hdl.handle.net/2433/235070.

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Lizy-Destrez, Stéphanie. "Operational scenarios optimization for resupply of crew and cargo of an International gateway Station located near the Earth-Moon-Lagrangian point-2." Thesis, Toulouse, ISAE, 2015. http://www.theses.fr/2015ESAE0034/document.

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Ce projet se place dans le contexte des futures missions habitées d’exploration du système solaire (avec un horizon de 2025), en respect de la feuille de route proposée par l’ISECG (International Space Exploration Coordination Group) [1]. Une nouvelle avancée serait de maintenir, à un des points de Lagrange du système Terre-Lune, en avant-poste, une station spatiale qui faciliterait l’accès vers les destinations telles que la Lune, Mars et les astéroïdes et permettrait de tester certaines technologies, notamment avant de les employer pour des missions plus lointaines. Un des principaux défis s
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Liot, Olivier. "Approches innovantes en convection thermique turbulente. Influence des rugosités et étude Lagrangienne." Thesis, Lyon, École normale supérieure, 2015. http://www.theses.fr/2015ENSL1054/document.

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Lors de cette thèse nous avons étudié le phénomène de convection thermique turbulente. La compréhension des mécanismes du flux thermique induit est encore un défi. Dans cette optique, deux approches innovantes ont été utilisées. La première a consisté en une approche Lagrangienne. Dans un premier temps, nous avons immergé une particule instrumentée munie de capteurs de température. Sa vitesse a été mesurée simultanément afin de calculer le flux thermique local transporté. En comparant les mesures effectuées à des simulations numériques et à des mesures Eulériennes, la pertinence de cette métho
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Kuhlmann, Renke [Verfasser], Christof [Akademischer Betreuer] Büskens, Christof [Gutachter] Büskens, and Philip E. [Gutachter] Gill. "A Primal-Dual Augmented Lagrangian Penalty-Interior-Point Algorithm for Nonlinear Programming / Renke Kuhlmann ; Gutachter: Christof Büskens, Philip E. Gill ; Betreuer: Christof Büskens." Bremen : Staats- und Universitätsbibliothek Bremen, 2018. http://d-nb.info/1174669705/34.

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Silva, Alysson Alexander Naves. "Simulação numérica de escoamentos bidimensionais com superfícies livres e linhas de contato dinâmicas." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-22062010-145307/.

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Um método lagrangeano-euleriano arbitrário para a resolução de escoamentos dominados por tensão superficial é apresentado neste trabalho. Tais escoamentos são importantes em muitas aplicações, especialmente em canais capilares que frequentemente aparecem em escoamentos em microescala. A resolução deste tipo de escoamento apresenta vários desafios que são abordados neste trabalho. O escoamento é resolvido somente para a fase líquida, com condições de contorno apropriadas para a superfície livre que delimita o líquido e o gás, que é representada por arestas e vértices da malha computacional. Est
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Lizy-Destrez, Stéphanie [Verfasser], and Ernst [Akademischer Betreuer] Messerschmid. "Operational scenarios optimization for resupply of crew and cargo of an International gateway Station located near the Earth-Moon-Lagrangian point-2 / Stéphanie Lizy-Destrez ; Betreuer: Ernst Messerschmid." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2016. http://d-nb.info/111850772X/34.

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Books on the topic "Lagrangian point"

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service), SpringerLink (Online, ed. Critical Point Theory for Lagrangian Systems. Springer Basel AG, 2012.

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Mazzucchelli, Marco. Critical Point Theory for Lagrangian Systems. Springer Basel, 2012. http://dx.doi.org/10.1007/978-3-0348-0163-8.

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Ambrosetti, A. Periodic solutions of singular Lagrangian systems. Birkhäuser, 1993.

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K, Prasad. Simulation studies on cyclone track prediction by quasi-lagrangian model (QLM) in some historical and recent cases in the Bay of Bengal, using global re-analysis and forecast grid point data sets. SAARC Meteorological Research Centre, 2006.

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Baldomá, Inmaculada. Exponentially small splitting of invariant manifolds of parabolic points. American Mathematical Society, 2004.

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Mann, Peter. Point Transformations in Lagrangian Mechanics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198822370.003.0009.

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This chapter discusses point transformations in Lagrangian mechanics. Sometimes, when solving problems, it is useful to change coordinates in velocity phase space to better suit and simplify the system at hand; this is a requirement of any physical theory. This change is often motivated by some experimentally observed physicality of the system or may highlight new conserved quantities that might have been overlooked using the old description. In the Newtonian formalism, it was a bit of a hassle to change coordinates and the equations of motion will look quite different. In this chapter, point
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Mazzucchelli, Marco. Critical Point Theory for Lagrangian Systems. Springer, 2011.

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Ambrosetti, A. Periodic Solutions of Singular Lagrangian Systems. Springer, 2013.

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Kachelriess, Michael. Classical mechanics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198802877.003.0001.

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This chapter reviews those concepts of classical mechanics which are essential for progressing towards quantum theory. The Lagrangian and Hamiltonian formulation of classical mechanics are derived from action principles. The Green function method is illustrated and the action of a relativistic point particle recalled.
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Mann, Peter. Poisson Brackets & Angular Momentum. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198822370.003.0017.

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This chapter discusses canonical transformations and gauge transformations and is divided into three sections. In the first section, canonical coordinate transformations are introduced to the reader through generating functions as the extension of point transformations used in Lagrangian mechanics, with the harmonic oscillator being used as an example of a canonical transformation. In the second section, gauge theory is discussed in the canonical framework and compared to the Lagrangian case. Action-angle variables, direct conditions, symplectomorphisms, holomorphic variables, integrable syste
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Book chapters on the topic "Lagrangian point"

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Mazzucchelli, Marco. "Lagrangian and Hamiltonian Systems." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_1.

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Mazzucchelli, Marco. "The Morse Indices in Lagrangian Dynamics." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_2.

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Mazzucchelli, Marco. "Functional Setting for the Lagrangian Action." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_3.

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Mazzucchelli, Marco. "Periodic Orbits of Tonelli Lagrangian Systems." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_6.

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Mazzucchelli, Marco. "Local Homology and Hilbert Subspaces." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_5.

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Mazzucchelli, Marco. "Discretizations." In Critical Point Theory for Lagrangian Systems. Springer Basel, 2011. http://dx.doi.org/10.1007/978-3-0348-0163-8_4.

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Schmidt, D. S. "The Stability of the Lagrangian Point L4." In Applications of Computer Technology to Dynamical Astronomy. Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0985-4_34.

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Sritharan, Sivaguru S., and Meng Xu. "Malliavin Calculus for Stochastic Point Vortex and Lagrangian Models." In Seminar on Stochastic Analysis, Random Fields and Applications VII. Springer Basel, 2013. http://dx.doi.org/10.1007/978-3-0348-0545-2_11.

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Benzi, Michele, and Fatemeh Panjeh Ali Beik. "Uzawa-Type and Augmented Lagrangian Methods for Double Saddle Point Systems." In Structured Matrices in Numerical Linear Algebra. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-04088-8_11.

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Daniel, Patrik, Matej Medl’a, Karol Mikula, and Mariana Remešíková. "Reconstruction of Surfaces from Point Clouds Using a Lagrangian Surface Evolution Model." In Lecture Notes in Computer Science. Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-18461-6_47.

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Conference papers on the topic "Lagrangian point"

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Keiser, R., B. Adams, D. Gasser, P. Bazzi, P. Dutre, and M. Gross. "A unified Lagrangian approach to solid-fluid animation." In Point-Based Graphics 2005. IEEE, 2005. http://dx.doi.org/10.1109/pbg.2005.194073.

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Švančara, P., P. Hrubcová, and M. La Mantia. "MULTI-POINT LAGRANGIAN VELOCITY ESTIMATES." In Topical Problems of Fluid Mechanics 2018. Institute of Thermomechanics, AS CR, v.v.i., 2018. http://dx.doi.org/10.14311/tpfm.2018.038.

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Wong, Brian, and Arun Misra. "Dynamics of Flexible Appendages Mounted on Lagrangian Point Satellites." In 57th International Astronautical Congress. American Institute of Aeronautics and Astronautics, 2006. http://dx.doi.org/10.2514/6.iac-06-c1.3.03.

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Chai, Patrick, and Alan Wilhite. "Station Keeping for Earth-Moon Lagrangian Point Exploration Architectural Assets." In AIAA SPACE 2012 Conference & Exposition. American Institute of Aeronautics and Astronautics, 2012. http://dx.doi.org/10.2514/6.2012-5112.

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Gao, Rui, and Simo Sarkka. "Augmented Sigma-Point Lagrangian Splitting Method for Sparse Nonlinear State Estimation." In 2020 28th European Signal Processing Conference (EUSIPCO). IEEE, 2021. http://dx.doi.org/10.23919/eusipco47968.2020.9287731.

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Okulicka- Dłużewska, Felicja. "On optimal coefficient in augmented Lagrangian method for saddle point problem." In PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON NUMERICAL ANALYSIS AND APPLIED MATHEMATICS 2014 (ICNAAM-2014). AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4912878.

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IZUMIYA, Shyuichi. "DIFFERENTIAL GEOMETRY FROM THE VIEW POINT OF LAGRANGIAN OR LEGENDRIAN SINGULARITY THEORY." In Proceedings of the 2005 Marseille Singularity School and Conference. WORLD SCIENTIFIC, 2007. http://dx.doi.org/10.1142/9789812707499_0008.

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"Dynamics of a Tether Connected Formation Near the Second Sun-Earth Lagrangian Point." In 55th International Astronautical Congress of the International Astronautical Federation, the International Academy of Astronautics, and the International Institute of Space Law. American Institute of Aeronautics and Astronautics, 2004. http://dx.doi.org/10.2514/6.iac-04-a.5.09.

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Ma, Xu, and Nicola Elia. "A sufficient saddle point characterization for the Lagrangian associated with general OPF problems." In 2014 IEEE 53rd Annual Conference on Decision and Control (CDC). IEEE, 2014. http://dx.doi.org/10.1109/cdc.2014.7039531.

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Premchand, C. P., Nitin B. George, Manikandan Raghunathan, Vishnu R. Unni, R. I. Sujith, and Vineeth Nair. "Lagrangian Saddle Point Analysis in the Flow-Field of a Bluff-Body Stabilized Combustor." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-91713.

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Abstract Experiments are performed in a partially-premixed bluff-body stabilized turbulent combustor by varying the mean flow velocity. Simultaneous measurements obtained for unsteady pressure, velocity and heat release rate are used to investigate the dynamic regimes of intermittency (10.1 m/s) and thermoacoustic instability (12.3 m/s). Using wavelet analysis, we show that during intermittency, modulation of heat release rate occurring at the acoustic frequency fa by the heat release rate occurring at the hydrodynamic frequency fh results in epochs of heat release rate fluctuations where the
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