Bibliografias temáticas / Exponential decay of correlation functions

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Literatura científica selecionada sobre o tema "Exponential decay of correlation functions"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 3 de fevereiro de 2022

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Artigos de revistas sobre o assunto "Exponential decay of correlation functions"

Poghosyan, H. R., H. M. Babujian e G. K. Savvidy. "Artin Billiard: Exponential Decay of Correlation Functions". Theoretical and Mathematical Physics 197, n.º 2 (novembro de 2018): 1592–610. http://dx.doi.org/10.1134/s004057791811003x.

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Kashima, Yohei. "Exponential decay of correlation functions in many-electron systems". Journal of Mathematical Physics 51, n.º 6 (junho de 2010): 063521. http://dx.doi.org/10.1063/1.3409395.

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COURBAGE, M., e D. HAMDAN. "Decay of correlations and mixing properties in a dynamical system with zero K–S entropy". Ergodic Theory and Dynamical Systems 17, n.º 1 (fevereiro de 1997): 87–103. http://dx.doi.org/10.1017/s0143385797061051.

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We consider the ergodic skew product of translations on the torus ${\Bbb T}^{2}$. We characterize a class of smooth functions with exponential correlation decay rate and a class of subsets with an exponential rate of mixing. We show that the class of functions with sub-exponential correlation decay rate is generic. We also characterize another class of subsets with mixing rate of the order of $1/t$.

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OKABE, Yasunori, e Akihiko INOUE. "On the exponential decay of the correlation functions for KMO-Langevin equations". Japanese journal of mathematics. New series 18, n.º 1 (1992): 13–24. http://dx.doi.org/10.4099/math1924.18.13.

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FINE, BORIS V. "LONG-TIME RELAXATION ON SPIN LATTICE AS A MANIFESTATION OF CHAOTIC DYNAMICS". International Journal of Modern Physics B 18, n.º 08 (30 de março de 2004): 1119–59. http://dx.doi.org/10.1142/s0217979204024689.

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The long-time behavior of the infinite temperature spin correlation functions describing the free induction decay in nuclear magnetic resonance and intermediate structure factors in inelastic neutron scattering is considered. These correlation functions are defined for one-, two- and three-dimensional infinite lattices of interacting spins, both classical and quantum. It is shown that, even though the characteristic time-scale of the long-time decay of the correlation functions considered is non-Markovian, the generic functional form of this decay is either simple exponential or exponential multiplied by cosine. This work contains (i) the summary of the existing experimental and numerical evidence of the above asymptotic behavior; (ii) theoretical explanation of this behavior; and (iii) semi-empirical analysis of various factors discriminating between the monotonic and the oscillatory long-time decays. The theory is based on a fairly strong conjecture that, as a result of chaos generated by spin dynamics, a Brownian-like Markovian description can be applied to the long-time properties of ensemble average quantities on a non-Markovian time-scale. The formalism resulting from that conjecture can be described as "correlated diffusion in finite volumes."

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Braga, Gastão A., Paulo C. Lima e Michael L. O'Carroll. "Exponential Decay of Truncated Correlation Functions Via the Generating Function: A Direct Method". Reviews in Mathematical Physics 10, n.º 04 (maio de 1998): 429–38. http://dx.doi.org/10.1142/s0129055x98000136.

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We consider statistical mechanics lattice models where the external field dependent partition function can be represented as a standard polymer system. Using this polymer representation and elementary complex analytic arguments, we obtain upper bounds and give a simple proof on the uniform (in n) exponential decay of the n-point truncated correlation function. We illustrate the method by applying it to the high and low temperature Ising model and to contour models.

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MARINO, E. C. "A NEW QUANTUM VORTEX OPERATOR AND ITS CORRELATION FUNCTIONS". International Journal of Modern Physics A 10, n.º 30 (10 de dezembro de 1995): 4311–24. http://dx.doi.org/10.1142/s0217751x95001996.

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A new local and gauge-invariant quantum vortex operator is constructed in three-dimensional gauge field theories. The correlation functions of this operator are evaluated exactly in pure Maxwell theory and by means of an expansion around a constant absolute value of the Higgs field in the Abelian Higgs model. In the broken symmetry phase of the latter an explicit expression for the mass of the quantum vortices is obtained from the long distance exponential decay of the two-point function.

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Göhmann, F., A. G. Izergin, V. E. Korepin e A. G. Pronko. "Time and Temperature Dependent Correlation Functions of the One-Dimensional Impenetrable Electron Gas". International Journal of Modern Physics B 12, n.º 23 (20 de setembro de 1998): 2409–33. http://dx.doi.org/10.1142/s0217979298001411.

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We consider the one-dimensional delta-interacting electron gas in the case of infinite repulsion. We use determinant representations to study the long time, large distance asymptotics of correlation functions of local fields in the gas phase. We derive differential equations which drive the correlation functions. Using a related Riemann–Hilbert problem we obtain formulae for the asymptotics of the correlation functions, which are valid at all finite temperatures. At low temperatures these formulae lead to explicit asymptotic expressions for the correlation functions, which describe power law behavior and exponential decay as functions of temperature, magnetic field and chemical potential.

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Savvidy, George, e Konstantin Savvidy. "Exponential decay of correlations functions in MIXMAX generator of pseudorandom numbers". Chaos, Solitons & Fractals 107 (fevereiro de 2018): 244–50. http://dx.doi.org/10.1016/j.chaos.2018.01.007.

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Stolze, Joachim, Angela Nöppert e Gerhard Müller. "Gaussian, exponential, and power-law decay of time-dependent correlation functions in quantum spin chains". Physical Review B 52, n.º 6 (1 de agosto de 1995): 4319–26. http://dx.doi.org/10.1103/physrevb.52.4319.

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Mais fontes

Teses / dissertações sobre o assunto "Exponential decay of correlation functions"

Nakano, Yushi. "Stochastic Stability of Partially Expanding Maps via Spectral Approaches". Kyoto University, 2015. http://hdl.handle.net/2433/200463.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第19200号
人博第741号
新制||人||178(附属図書館)
27||人博||741(吉田南総合図書館)
32192
京都大学大学院人間・環境学研究科共生人間学専攻
(主査)教授宇敷重廣, 教授森本芳則, 准教授木坂正史
学位規則第4条第1項該当

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Moazzezi, Mojtaba. "Quantum Coherence Effects Coupled via Plasmons". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404550/.

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This thesis is an attempt at studying quantum coherence effects coupled via plasmons. After introducing the quantum coherence in atomic systems in Chapter 1, we utilize it in Chapter 2 to demonstrate a new technique of detection of motion of single atoms or irons inside an optical cavity. By taking into account the interaction of coherences with surface plasmonic waves excited in metal nanoparticles, we provide a theoretical model along with experimental data in Chapter 3 to describe the modification of Raman spectra near metal nanoparticles. We show in chapter 4 that starting from two emitters, coupled via a plasmonic field, the symmetry breaking occurs, making detectable the simultaneous existence of the fast super-radiance and the slow sub-radiance emission of dye fluorescence near a plasmonic surface. In Chapter 5, we study the photon statistics of a group of emitters coupled via plasmons and by the use of quantum regression theorem, we provide a theoretical model to fully investigate the dependence of photon bunching and anti-bunching effects to the interaction between atoms, fields and surrounding mediums.

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Schäfer, Rudi. "Correlation functions and fidelity decay in chaotic systems". [S.l. : s.n.], 2004. http://archiv.ub.uni-marburg.de/diss/z2004/0660/.

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TADDEI, MARIA H. T. "Determinação de fatores de escala para estimativa do inventário de radionuclídeos em rejeitos de média e baixa atividade do reator IEA-R1". reponame:Repositório Institucional do IPEN, 2013. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10569.

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Made available in DSpace on 2014-10-09T12:42:05Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:04:50Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Schäfer, Rudi [Verfasser]. "Correlation functions and fidelity decay in chaotic systems / by Rudi Schäfer". 2004. http://d-nb.info/973876840/34.

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Sebatjane, Phuti. "Understanding patterns of aggregation in count data". Diss., 2016. http://hdl.handle.net/10500/22067.

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The term aggregation refers to overdispersion and both are used interchangeably in this thesis. In addressing the problem of prevalence of infectious parasite species faced by most rural livestock farmers, we model the distribution of faecal egg counts of 15 parasite species (13 internal parasites and 2 ticks) common in sheep and goats. Aggregation and excess zeroes is addressed through the use of generalised linear models. The abundance of each species was modelled using six different distributions: the Poisson, negative binomial (NB), zero-inflated Poisson (ZIP), zero-inflated negative binomial (ZINB), zero-altered Poisson (ZAP) and zero-altered negative binomial (ZANB) and their fit was later compared. Excess zero models (ZIP, ZINB, ZAP and ZANB) were found to be a better fit compared to standard count models (Poisson and negative binomial) in all 15 cases. We further investigated how distributional assumption a↵ects aggregation and zero inflation. Aggregation and zero inflation (measured by the dispersion parameter k and the zero inflation probability) were found to vary greatly with distributional assumption; this in turn changed the fixed-effects structure. Serial autocorrelation between adjacent observations was later taken into account by fitting observation driven time series models to the data. Simultaneously taking into account autocorrelation, overdispersion and zero inflation proved to be successful as zero inflated autoregressive models performed better than zero inflated models in most cases. Apart from contribution to the knowledge of science, predictability of parasite burden will help farmers with effective disease management interventions. Researchers confronted with the task of analysing count data with excess zeroes can use the findings of this illustrative study as a guideline irrespective of their research discipline. Statistical methods from model selection, quantifying of zero inflation through to accounting for serial autocorrelation are described and illustrated.
Statistics
M.Sc. (Statistics)

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Capítulos de livros sobre o assunto "Exponential decay of correlation functions"

Chen, Sow-Hsin, E. Y. Sheu e J. S. Huang. "Non-exponential Decay of Density Correlation Function in Dense Microemulsions". In Springer Proceedings in Physics, 96–113. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-93419-3_11.

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Cox, Maurice G. "Modelling Clinical Decay Data Using Exponential Functions". In Approximation Algorithms for Complex Systems, 183–203. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-16876-5_8.

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Moore, Calvin C. "Exponential Decay of Correlation Coefficients for Geodesic Flows". In Mathematical Sciences Research Institute Publications, 163–81. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-4722-7_6.

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Noriega, J. M., L. Pesquera, M. A. Rodríguez, J. Casademunt e A. Hernández-Machado. "Analysis of the Decay of Intensity Correlation Functions for the Gain-Noise Model of Dye Lasers". In Springer Proceedings in Physics, 313–17. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76373-1_39.

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Zinn-Justin, Jean. "Critical phenomena: General considerations. Mean-field theory (MFT)". In Quantum Field Theory and Critical Phenomena, 324–56. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0014.

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This chapter is devoted to a brief review of general properties of phase transitions in macroscopic physics and, in particular in lattice models. Some of these lattice models actually appear as lattice regularizations of Euclidean (imaginary time) quantum physics theory (QFT). Most of the transitions considered in this work have the following character: spins on the lattice, or macroscopic particles in the continuum, interact through short-range forces, assumed, for simplicity, to decay exponentially. For simple systems, it is possible to find a local observable, called order parameter, whose expectation values depend on the phase in the several phase region, for example, the spin in ferromagnetic systems. In the disordered phase, the connected two-point function decreases exponentially at large distance, at a rate characterized by the correlation length (the inverse of the smallest physical mass in particle physics). In continuous transitions, the correlation length diverges at the critical temperature. Within the mean-field approximation (consistent with Landau's theory of critical phenomena), it can be shown that the singular behaviour of thermodynamic quantities at the critical temperature is universal. These properties can also be reproduced by calculating correlation functions with a perturbed Gaussian measure. It is then shown that the leading corrections to the mean-field approximation, in Ising-like systems, diverge at the critical temperature for dimensions smaller than or equal to $4$.

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Barriot, Jean-Pierre, e Peng Feng. "Beyond Mapping Functions and Gradients". In Geodetic Sciences - Theory, Applications and Recent Developments [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96982.

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Mapping functions and gradients in GNSS and VLBI applications were introduced in the sixties and seventies to model the microwave propagation delays in the troposphere, and they were proven to be the perfect tools for these applications. In this work, we revisit the physical and mathematical basis of these tools in the context of meteorology and climate applications and propose an alternative approach for the wet delay part. This alternative approach is based on perturbation theory, where the base case is an exponential decay of the wet refractivity with altitude. The perturbation is modeled as a set of orthogonal functions in space and time, with the ability to separate eddy-scale variations of the wet refractivity.

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Ammar, Abdallah, Arnaud Leclerc e Lorenzo Ugo Ancarani. "Multicenter integrals involving complex Gaussian-type functions". In New Electron Correlation Methods and their Applications, and Use of Atomic Orbitals with Exponential Asymptotes, 287–304. Elsevier, 2021. http://dx.doi.org/10.1016/bs.aiq.2021.05.006.

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Van Brummelen, Glen. "6. and beyond, to complex things". In Trigonometry: A Very Short Introduction, 109–27. Oxford University Press, 2020. http://dx.doi.org/10.1093/actrade/9780198814313.003.0006.

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‘ … and beyond, to complex things’ first considers the Taylor series for the exponential function. One of the most famous, yet enigmatic, numbers in mathematics, e is an irrational number equal to 2.718281828. … Exponential functions deal with the phenomena of growth and decay. As calculus was starting to become established, curious parallels between the apparently disparate worlds of trigonometry and exponential functions were starting to appear. Imaginary numbers, Euler’s formula, and Euler’s identity are discussed along with the Argand diagram, De Moivre’s formula, hyperbolic trigonometric functions, and the catenary curve. Imaginary numbers are now at the heart of science and technology, and are used in the study of electromagnetic waves, cellular and wireless technologies, and fluid dynamics.

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Mitnik, Dario, Ana Laura Frapiccini e Lorenzo Ugo Ancarani. "Generalized Sturmian Functions in prolate spheroidal coordinates: Continuum states". In New Electron Correlation Methods and their Applications, and Use of Atomic Orbitals with Exponential Asymptotes, 239–53. Elsevier, 2021. http://dx.doi.org/10.1016/bs.aiq.2021.05.002.

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Weniger, Ernst Joachim. "Are B functions with nonintegral orders a computationally useful basis set?" In New Electron Correlation Methods and their Applications, and Use of Atomic Orbitals with Exponential Asymptotes, 209–37. Elsevier, 2021. http://dx.doi.org/10.1016/bs.aiq.2021.06.002.

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Trabalhos de conferências sobre o assunto "Exponential decay of correlation functions"

Bao, Xingxian, Zhihui Liu e Chen Shi. "Processing of Ambient Vibration Response for Modal Parameters Identification of a Jacket-Type Offshore Platform: Sea Test Study". In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77018.

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Modal parameters identification of offshore structures is important for many engineering applications, such as damage detection, structural health monitoring, etc. Operational modal analysis has been widely used for large structures. However, measured signals are inevitably contaminated with noise and may not be clean enough for identifying the modal parameters with proper accuracy. The traditional methods to estimate modal parameters in noisy situation are based on over-determined system to absorb the “noise modes” firstly, and then using the stability diagrams to distinguish the true modes from the “noise modes”. However, it is difficult to sort out true modes when the signal noise ratio is low, especially, the “noise modes” will also tend to be stable as the model order increases. This study develops a noise reduction procedure for polyreference complex exponential (PRCE) modal analysis based on ambient vibration responses. In the procedure, natural excitation technique (NExT) is firstly applied to get free decay responses (auto- and cross-correlation functions) from measured (noisy) ambient vibration data, and then the noise reduction method based on solving the partially described inverse singular value problem (PDISVP) is implemented to reconstruct a filtered data matrix from the measured data matrix. In our case, the measured data matrix is block Hankel structured, which is constructed based on the free decay responses. The filtered data matrix should maintain the block Hankel structure and be lowered in rank. When the filtered data matrix is obtained, the PRCE method is applied to estimate the modal parameters. The proposed NExT-PDISVP-PRCE scheme is applied to field test of a jacket type offshore platform. Results indicate that the proposed method can improve the accuracy of operational modal analysis.

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Ada´nez, Juan, Luis F. de Diego, Pilar Gaya´n, Francisco Garci´a-Labiano, Andre´s Cabanillas e Alberto Bahillo. "Co-Combustion of Biomass and Coal in Circulating Fluidized Bed: Modeling and Validation". In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-064.

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In this work carbon combustion efficiencies in circulating fluidized bed combustion (CFBC) when co-firing biomass and coal mixtures were studied. Experimental results were obtained from the combustion of two kind of coals with a forest residue (Pine bark) in a CBF pilot plant (0.3MWth) with 20-cm i.d. and 6.5-m height. The effect of operating conditions such as percentage of biomass in the feed, temperature, excess air, air velocity and percentage of secondary air on carbon combustion efficiency was studied. A mathematical model for the co-combustion of coal and biomass in a circulating fluidized bed boiler has been developed. The riser is divided in three zones with different hydrodynamic characteristics: bottom, splash and freeboard. The bottom bed has a constant voidage, determined by a modified two-phase theory. The solids are considered in perfect mixing and the gas in plug flow. The voidage in the splash region follows an exponential decay model. In the freeboard region, the solids and the gas are in plug flow, and a core-annulus structure is considered. Devolatilization of solid fuels is modeled with a particle reaction model which allows to determine the volatiles generation rate as a function of time and operating conditions. Kinetics of char combustion is modeled with the shrinking particle model with mixed control by chemical reaction and gas film diffusion, assuming that the ashes separate once formed. To consider that the char particles are a mixture of coal and biomass char particles, a weighted average combustion rate is defined taking into account the individual combustion rates. Population balances of char particles in the different regions were developed to calculate carbon concentrations. The developed model can predict the different gas concentrations along the riser, such as oxygen, SO2, CO, CH4, etc..., and the carbon combustion efficiency. The experimental results of carbon combustion efficiencies and gas emissions were compared with those predicted by the model and a good correlation was found for all the conditions used.

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Xu, Peng, e Jian-Cheng Shi. "Reduced absorpton and beam broadening of transmission from LHM surfaces with exponential correlation functions". In 2014 XXXIth URSI General Assembly and Scientific Symposium (URSI GASS). IEEE, 2014. http://dx.doi.org/10.1109/ursigass.2014.6929107.

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Harrow, Aram W., Saeed Mehraban e Mehdi Soleimanifar. "Classical algorithms, correlation decay, and complex zeros of partition functions of quantum many-body systems". In STOC '20: 52nd Annual ACM SIGACT Symposium on Theory of Computing. New York, NY, USA: ACM, 2020. http://dx.doi.org/10.1145/3357713.3384322.

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Xu, Peng, Leung Tsang e Kun Shan Chen. "Numerical Simulations of Emission and Bistatic Scattering from Soils with Rough Surfaces of Exponential Correlation Functions". In IGARSS 2008 - 2008 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2008. http://dx.doi.org/10.1109/igarss.2008.4780041.

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Pham-Xuan, V., D. Trinh, T. Do-Hong e C. Brennan. "Improved Forward Backward Method with Multiple Correction Vectors for Layered Random Rough Surfaces of Exponential Correlation Functions". In 2018 International Conference on Advanced Technologies for Communications (ATC). IEEE, 2018. http://dx.doi.org/10.1109/atc.2018.8587504.

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Someya, Satoshi, Yanrong Li, Kaoru Tominaga, Manabu Tange e Koji Okamoto. "Combined Measurement of Temperature and Velocity Distribution of Fluid Flow". In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22504.

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This paper proposes a combined method for two-dimensional temperature and velocity measurement using temperature sensitive particles (TSPs), a pulsed ultraviolet laser, and a high-speed camera. TSPs respond to temperature changes in a flow and can also serve as tracers for the velocity field. The luminescence from the TSPs was recorded at 15,000 frames per second as sequential images for a lifetime-based temperature analysis. These images were also used for the particle image velocimetry calculations. The temperature field was estimated using six images, based on the lifetime method. The decay curves for various temperature conditions fit well to exponential functions, and from these the decay constants at each temperature were obtained. The proposed technique was applied to measure the temperature and velocity fields in natural convection driven by a Marangoni force and buoyancy in a rectangular tank. The accuracy of the temperature measurement of the proposed technique was ±0.35∼0.40°C.

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Hauser, Eliete Biasotto, Ruben Panta Pazos, Marco T. M. B. Vilhena e Ricardo C. Barros. "The Error Bounds for Three-Dimensional Nodal LTSN Method". In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48739.

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In this paper we present a proof about the convergence of the 3D Nodal-LTSN Method in order to solve the transport problem in a parallelepiped domain. For that, we define functions associated to the errors, one in the approximated flux, another in the quadrature formula and establish a relation between them. We present a Nodal-LTSN method to generate an analytical solution for discrete ordinates problems in three-dimensional cartesian geometry. We first transverse integrate the SN equations and then we apply the Laplace transform. The essence of this method is the diagonalization of the LTSN transport matrices and the spectral analysis garantees this. The transverse leakage terms that appear in the transverse integrated SN equations are represented by exponential functions with decay constants that depend on the characteristics of the material of the medium the particles leave behind. We present numerical results generated by the offered method applied to typical shielding model problems.

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Khodabandelou, Babak, Kaveh Abasi e Masud Asayesh. "Reliability of Extracted Modal Parameters by Random Decrement of Acceleration Signatures". In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12304.

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Modal parameters provide important information on dynamic properties of structures. In operating condition, since it is difficult to measure input loadings, methods should be applied where don’t require measuring inputs. Such methods which identify modal parameters of structures by measuring their responses are called Operational- or Output Only- Modal Analysis (OMA) techniques. There are many time and frequency domain operational modal analysis techniques. Generally a form of impulse or free vibration response is required to use most of these techniques. However, in practice structures are usually subjected to some immeasurable or unknown random inputs. In these situations Random Decrement (RD) transformation can reduce these responses to equivalent free decay or correlation functions. Therefore, RD technique coupled with those methods, which require a form of impulse or free vibration response offer a valuable tool for identifying the dynamic characteristics of structures from operational or ambient responses. Unfortunately, in the literature there are some constrains on using random decrement signatures. For example by complicated mathematical relations it is shown that random decrement technique is applicable only if the inputs are uncorrelated zero mean Gaussian white noises. In addition, it is proved that only random decrement of displacement and velocity is equivalent to the corresponding free decay responses or correlation functions the random decrement of acceleration response is never equivalent to the corresponding free decay responses or correlation functions. However, there are many papers which have used random decrement of acceleration responses and extracted modal parameters accurately! In this paper it is tried to show simply and clearly whether it is possible to obtain modal parameters from random decrement acceleration signatures or not. To do that, a numerical simulation of a discrete dynamic system with viscous damping is carried out and the results of numerical methods are compared with those come from analytical solution. Numerical simulation is used since it is completely controllable. Finally, it is tried to identify power and the Applicability cases of random decrement method.

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Chang, Haiping, Jingyu Zhang e Taiping Huang. "Experimental Investigation on Impingement Heat Transfer From Rib Roughened Surface Within Arrays of Circular Jets: Correlation". In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0220.

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Impingement heat transfer is one of the useful cooling methods for high temperature gas turbine blades and/or guide vanes in aeroengines. After the cooling jet impinges on the leading edge of the turbine blade and/or guide vane, it flows downstream and turns to be the initial crossflow for the aft row of impinging jet. The process of impingement heat transfer is quite complicated, especially when the target surface is rib roughened. In this paper, the correlation of the impingement heat transfer characteristics has been analyzed based on thousands of experimental data in different parameter matching conditions (Ref = 7000∼20000, Gc/Gj = 0∼0.5, Xn = 5∼15, Zn = 1.5∼5, p/e = 5∼12 and e/d = 0.5∼1.5). The impingement heat transfer characteristics can be generally expressed as a functional formulation with the exponential functions of Ref, Zn, Xn, e/d and p/e, and a polynomial function of Gc/Gj. The interaction among the parameters are reflected in the exponents i, j, k, n, etc. and the weighing coefficients. By the regression processing to the experimental data, the exponents and the weighing coefficients are determined. The correlation equation of impingement heat transfer characteristics to the parameters has been finally concluded. Comparison shows that the correlation results are in good agreement with the experimental data.

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