Relevant bibliographies by topics / Exact Renomalization Group Methods

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Exact Renomalization Group Methods'

Author: Grafiati
Published: 4 June 2021
Last updated: 12 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Exact Renomalization Group Methods.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Exact Renomalization Group Methods"

1

Chen, Zhengjia, and Xinjia Chen. "Exact Group Sequential Methods for Estimating a Binomial Proportion." Journal of Probability and Statistics 2013 (2013): 1–24. http://dx.doi.org/10.1155/2013/603297.

Full text
Abstract:
We first review existing sequential methods for estimating a binomial proportion. Afterward, we propose a new family of group sequential sampling schemes for estimating a binomial proportion with prescribed margin of error and confidence level. In particular, we establish the uniform controllability of coverage probability and the asymptotic optimality for such a family of sampling schemes. Our theoretical results establish the possibility that the parameters of this family of sampling schemes can be determined so that the prescribed level of confidence is guaranteed with little waste of samples. Analytic bounds for the cumulative distribution functions and expectations of sample numbers are derived. Moreover, we discuss the inherent connection of various sampling schemes. Numerical issues are addressed for improving the accuracy and efficiency of computation. Computational experiments are conducted for comparing sampling schemes. Illustrative examples are given for applications in clinical trials.
APA, Harvard, Vancouver, ISO, and other styles
2

TISSIER, M., B. DELAMOTTE, and D. MOUHANNA. "AN EXACT RENORMALIZATION GROUP APPROACH TO FRUSTRATED MAGNETS." International Journal of Modern Physics A 16, no. 11 (April 30, 2001): 2131–36. http://dx.doi.org/10.1142/s0217751x01004827.

Full text
Abstract:
Frustrated magnets are a notorious example where usual perturbative methods fail. Having recourse to an exact renormalization group approach, one gets a coherent picture of the physics of Heisenberg frustrated magnets everywhere between d=2 and d=4: all known perturbative results are recovered in a single framework, their apparent conflict is explained while the description of the phase transition in d=3 is found to be in good agreement with the experimental context.
APA, Harvard, Vancouver, ISO, and other styles
3

Iwasa, M. "Reduction of Dynamics with Lie Group Analysis." Advances in Mathematical Physics 2012 (2012): 1–17. http://dx.doi.org/10.1155/2012/505281.

Full text
Abstract:
This paper is mainly a review concerning singular perturbation methods by means of Lie group analysis which has been presented by the author. We make use of a particular type of approximate Lie symmetries in those methods in order to construct reduced systems which describe the long-time behavior of the original dynamical system. Those methods can be used in analyzing not only ordinary differential equations but also difference equations. Although this method has been mainly used in order to derive asymptotic behavior, when we can find exact Lie symmetries, we succeed in construction of exact solutions.
APA, Harvard, Vancouver, ISO, and other styles
4

ROSNER, GARY L., and ANASTASIOS A. TSIATIS. "Exact confidence intervals following a group sequential trial: A comparison of methods." Biometrika 75, no. 4 (1988): 723–29. http://dx.doi.org/10.1093/biomet/75.4.723.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Kopietz, Peter, Lorenz Bartosch, Lucio Costa, Aldo Isidori, and Alvaro Ferraz. "Ward identities for the Anderson impurity model: derivation via functional methods and the exact renormalization group." Journal of Physics A: Mathematical and Theoretical 43, no. 38 (August 27, 2010): 385004. http://dx.doi.org/10.1088/1751-8113/43/38/385004.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Duncan, A. J., Graham J. Ellis, and N. D. Gilbert. "A Mayer-Vietoris sequence in group homology and the decomposition of relation modules." Glasgow Mathematical Journal 37, no. 2 (May 1995): 159–71. http://dx.doi.org/10.1017/s0017089500031062.

Full text
Abstract:
W. A. Bogley and M. A. Gutierrez [2] have recently obtained an eight-term exact homology sequence that relates the integral homology of a quotient group Г/MN, where M and N are normal subgroups of the group Г, to the integral homology of the free product Г/M * Г/N in dimensions ≤3 by means of connecting terms constructed from commutator subgroups of Г, M, N and M ∩ N. In this paper we use the methods of [4] to recover this exact sequence under weaker hypotheses and for coefficients in /q for any non-negative integer q. Further, for q = 0 we extend the sequence by three terms in order to capture the relation between the fourth homology groups.
APA, Harvard, Vancouver, ISO, and other styles
7

Carvalho, P. R. S., and M. I. Sena-Junior. "Exact Lorentz-violating q-deformed O(N) universality class." International Journal of Modern Physics D 28, no. 03 (February 2019): 1950050. http://dx.doi.org/10.1142/s0218271819500500.

Full text
Abstract:
We examine the influence of exact Lorentz-violating symmetry mechanism on the radiative quantum corrections to the critical exponents for massless [Formula: see text]-deformed O([Formula: see text]) [Formula: see text] scalar field theories. For that, we employ three different and independent field-theoretic renormalization group methods for computing analytically the [Formula: see text]-deformed critical exponents up to next-to-leading order. Then, we generalize the former finite loop level results for any loop order. We show that the Lorentz-violating [Formula: see text]-deformed critical exponents, obtained through the three methods, turn out to be identical and furthermore the same as their Lorentz-invariant [Formula: see text]-deformed ones. We argue that this result is in accordance with the universality hypothesis.
APA, Harvard, Vancouver, ISO, and other styles
8

Zhang, Bo, and Hengchun Hu. "Similarity Reduction and Exact Solutions of a Boussinesq-like Equation." Zeitschrift für Naturforschung A 73, no. 4 (March 28, 2018): 357–62. http://dx.doi.org/10.1515/zna-2017-0442.

Full text
Abstract:
AbstractThe similarity reduction and similarity solutions of a Boussinesq-like equation are obtained by means of Clarkson and Kruskal (CK) direct method. By using Lie symmetry method, we also obtain the similarity reduction and group invariant solutions of the model. Further, we compare the results obtained by the CK direct method and Lie symmetry method, and we demonstrate the connection of the two methods.
APA, Harvard, Vancouver, ISO, and other styles
9

Belinchón, José Antonio, and Pedro Dávila. "Exact solutions for a scalar-tensor theory through symmetries." International Journal of Geometric Methods in Modern Physics 14, no. 07 (March 16, 2017): 1750104. http://dx.doi.org/10.1142/s0219887817501043.

Full text
Abstract:
In this paper, we study how to determine the unknown functions for the scalar tensor model [Formula: see text] where the Ricci scalar is allowed to appear in a nonlinear way. The methods followed to determine these functions are: the matter collineation approach, the Lie group method and the Lagrangian collineation approach. We find several exact analytical solutions for a cosmological model with a FRW metric. We determine that some of the results are also valid for some anisotropic metric (e.g. the self-similar ones).
APA, Harvard, Vancouver, ISO, and other styles
10

Jamil, Bismah, Tooba Feroze, and Muhammad Safdar. "Optimal systems and their group-invariant solutions to geodesic equations." International Journal of Geometric Methods in Modern Physics 16, no. 09 (September 2019): 1950135. http://dx.doi.org/10.1142/s0219887819501354.

Full text
Abstract:
We find one-dimensional optimal systems of the Lie subalgebras of Noether symmetries associated with systems of geodesic equations. Further, we find invariants corresponding to each element of the derived optimal system. The derived invariants are shown to reduce systems of geodesic equations (nonlinear systems of quadratically semi-linear second-order ordinary differential equations (ODEs)) to nonlinear systems of first-order ODEs. The resulting systems are solved via known methods (e.g. separation of variables, integrating factor, etc.). In some cases, we provide exact solutions of these systems of geodesic equations.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Exact Renomalization Group Methods"

1

Nandori, Istvan. "Aspects of Non-Perturbative Renormalization." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2002. http://nbn-resolving.de/urn:nbn:de:swb:14-1036412015625-22668.

Full text
Abstract:
The goal of this Thesis is to give a presentation of some key issues regarding the non-perturbative renormalization of the periodic scalar field theories. As an example of the non-perturbative methods, we use the differential renormalization group approach, particularly the Wegner-Houghton and the Polchinski renormalization group equations, in order to investigate the renormalization of a one-component periodic scalar field theory. The Wegner-Houghton equation provides a resummation of the loop-expansion, and the Polchinski equation is based on the resummation of the perturbation series. Therefore, these equations are exact in the sense that they contain all quantum corrections. In the framework of these renormalization group equations, field theories with periodic self interaction can be considered without violating the essential symmetry of the model: the periodicity. Both methods - the Wegner-Houghton and the Polchinski approaches - are inspired by Wilson's blocking construction in momentum space: the Wegner-Houghton method uses a sharp momentum cut-off and thus cannot be applied directly to non-constant fields (contradicts with the "derivative expansion"); the Polchinski method is based on a smooth cut-off and thus gives rise naturally to a "derivative expansion" for varying fields. However, the shape of the cut-off function (the "scheme") is not fixed a priori within Polchinski's ansatz. In this thesis, we compare the Wegner--Houghton and the Polchinski equation; we demonstrate the consistency of both methods for near-constant fields in the linearized level and obtain constraints on the regulator function that enters into Polchinski's equation. Analytic and numerical results are presented which illustrate the renormalization group flow for both methods. We also briefly discuss the relation of the momentum-space methods to real-space renormalization group approaches. For the two-dimensional Coulomb gas (which is investigated by a real-space renormalization group method using the dilute-gas approximation), we provide a systematic method for obtaining higher-order corrections to the dilute gas result.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Exact Renomalization Group Methods"

1

Lavis, D., and Bell G. M. Statistical Mechanics of Lattice Systems 2: Exact, Series and Renormalization Group Methods. Springer Berlin Heidelberg, 2010.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Exact Renomalization Group Methods"

1

Stijnen, Theo, Christopher H. Schmid, Martin Law, Dan Jackson, and Ian R. White. "Exact Likelihood Methods for Group-Based Summaries." In Handbook of Meta-Analysis, 65–90. First edition. | Boca Raton : Taylor and Francis, [2020] | Series: Chapman & Hall/CRC handbooks of modern statistical methods: Chapman and Hall/CRC, 2020. http://dx.doi.org/10.1201/9781315119403-5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Cercignani, C. "Exact Solutions of the Boltzmann Equation." In Modern Group Analysis: Advanced Analytical and Computational Methods in Mathematical Physics, 125–36. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-2050-0_12.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Andreev, V. K., O. V. Kaptsov, V. V. Pukhnachov, and A. A. Rodionov. "Exact Solutions to the Equations of Dynamics for a Viscous Liquid." In Applications of Group-Theoretical Methods in Hydrodynamics, 271–382. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-0745-9_7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Leitz, Thomas, Sina Ober-Blöbaum, and Sigrid Leyendecker. "Variational Lie Group Formulation of Geometrically Exact Beam Dynamics: Synchronous and Asynchronous Integration." In Computational Methods in Applied Sciences, 175–203. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-07260-9_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Andreev, V. K., O. V. Kaptsov, V. V. Pukhnachov, and A. A. Rodionov. "Exact Solutions to the Nonstationary Euler Equations in the Presence of Planar and Rotational Symmetry." In Applications of Group-Theoretical Methods in Hydrodynamics, 68–127. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-0745-9_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

"Semi-group methods for construction of exact, approximated, and regularized solutions." In Stochastic Cauchy Problems in Infinite Dimensions, 3–41. Chapman and Hall/CRC, 2016. http://dx.doi.org/10.1201/b19955-3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Roman, O. "On the maximal symmetry group and exact solutions of non-linear higher order wave equations." In Integral methods in science and engineering, 155–59. Chapman and Hall/CRC, 2020. http://dx.doi.org/10.1201/9780367812027-31.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Dyall, Kenneth G., and Knut Faegri. "Correlation Methods." In Introduction to Relativistic Quantum Chemistry. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195140866.003.0018.

Full text
Abstract:
It is well known from nonrelativistic quantum chemistry that mean-field methods, such as the Hartree–Fock (HF) model, provide mainly qualitative insights into the electronic structure and bonding of molecules. To obtain reliable results of “chemical accuracy” usually requires models that go beyond the mean field and account for electron correlation. There is no reason to expect that the mean-field approach should perform significantly better in this respect for the relativistic case, and so we are led to develop schemes for introducing correlation into our models for relativistic quantum chemistry. There is no fundamental change in the concept of correlation between relativistic and nonrelativistic quantum chemistry: in both cases, correlation describes the difference between a mean-field description, which forms the reference state for the correlation method, and the exact description. We can also define dynamical and nondynamical correlation in both cases. There is in fact no formal difference between a nonrelativistic spin–orbital-based formalism and a relativistic spinor-based formalism. Thus we should be able to transfer most of the schemes for post-Hartree–Fock calculations to a relativistic post-Dirac–Hartree–Fock model. Several such schemes have been implemented and applied in a range of calculations. The main technical differences to consider are those arising from having to deal with integrals that are complex, and the need to replace algorithms that exploit the nonrelativistic spin symmetry by schemes that use time-reversal and double-group symmetry. In addition to these technical differences, however, there are differences of content between relativistic and nonrelativistic methods. The division between dynamical and nondynamical correlation is complicated by the presence of the spin–orbit interaction, which creates near-degeneracies that are not present in the nonrelativistic theory. The existence of the negative-energy states of relativistic theory raise the question of whether they should be included in the correlation treatment. The first two sections of this chapter are devoted to a discussion of these issues. The main challenges in the rest of this chapter are to handle the presence of complex integrals and to exploit time-reversal symmetry.
APA, Harvard, Vancouver, ISO, and other styles
9

Nechval, Nicholas A. "Intelligent Constructing Exact Tolerance Limits for Prediction of Future Outcomes Under Parametric Uncertainty." In Encyclopedia of Information Science and Technology, Fifth Edition, 701–29. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-3479-3.ch049.

Full text
Abstract:
The problem of constructing one-sided exact statistical tolerance limits on the kth order statistic in a future sample of m observations from a distribution of log-location-scale family on the basis of an observed sample from the same distribution is considered. The new technique proposed here emphasizes pivotal quantities relevant for obtaining tolerance factors and is applicable whenever the statistical problem is invariant under a group of transformations that acts transitively on the parameter space. The exact tolerance limits on order statistics associated with sampling from underlying distributions can be found easily and quickly making tables, simulation, Monte Carlo estimated percentiles, special computer programs, and approximation unnecessary. Finally, numerical examples are given, where the tolerance limits obtained by using the known methods are compared with the results obtained through the proposed novel technique, which is illustrated in terms of the extreme-value and two-parameter Weibull distributions.
APA, Harvard, Vancouver, ISO, and other styles
10

Zinn-Justin, Jean. "The random walk: Universality and continuum limit." In From Random Walks to Random Matrices, 1–12. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198787754.003.0001.

Full text
Abstract:
The first chapter discusses the asymptotic properties at large time and space of the familiar example of the random walk. The universality of a large scale behaviour and, correspondingly, the existence of a macroscopic continuum limit emerge as collective properties of systems involving a large number of random variables whose individual distribution is sufficiently localized. These properties, as well as the appearance of an asymptotic Gaussian distribution when the random variables are statistically independent, are illustrated with the simple example of the random walk with discrete time steps. The emphasis here is on locality, universality, continuum limit, path integral, Brownian motion, Gaussian distribution and scaling. These properties are first derived from an exact solution and then recovered by renormalization group (RG) methods. This makes it possible to introduce all the RG terminology.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Exact Renomalization Group Methods"

1

Andersen, O. K., O. Jepsen, and G. Krier. "Exact Muffin-Tin Orbital Theory." In Proceedings of the Miniworkshop on “Methods of Electronic Structure Calculations” and Working Group on “Disordered Alloys”. WORLD SCIENTIFIC, 1995. http://dx.doi.org/10.1142/9789814503778_0003.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Shi, Yuxuan, Gong Cheng, Trung-Kien Tran, Jie Tang, and Evgeny Kharlamov. "Keyword-Based Knowledge Graph Exploration Based on Quadratic Group Steiner Trees." In Thirtieth International Joint Conference on Artificial Intelligence {IJCAI-21}. California: International Joint Conferences on Artificial Intelligence Organization, 2021. http://dx.doi.org/10.24963/ijcai.2021/215.

Full text
Abstract:
Exploring complex structured knowledge graphs (KGs) is challenging for non-experts as it requires knowledge of query languages and the underlying structure of the KGs. Keyword-based exploration is a convenient paradigm, and computing a group Steiner tree (GST) as an answer is a popular implementation. Recent studies suggested improving the cohesiveness of an answer where entities have small semantic distances from each other. However, how to efficiently compute such an answer is open. In this paper, to model cohesiveness in a generalized way, the quadratic group Steiner tree problem (QGSTP) is formulated where the cost function extends GST with quadratic terms representing semantic distances. For QGSTP we design a branch-and-bound best-first (B3F) algorithm where we exploit combinatorial methods to estimate lower bounds for costs. This exact algorithm shows practical performance on medium-sized KGs.
APA, Harvard, Vancouver, ISO, and other styles
3

Zhu, W. D., and N. A. Zheng. "Exact Response of a Translating String With Arbitrarily Varying Length Under General Excitation." In ASME 2007 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/detc2007-34590.

Full text
Abstract:
The exact response of a translating string with constant tension and arbitrarily varying length is determined under general initial conditions and external excitation. The governing equation is transformed to a standard hyperbolic equation using characteristic transformation. The domain of interest for the transformed equation is divided into groups of sub-domains according to the properties of wave propagation. The d’Alembert’s solution for any point in the zeroth sub-domain group is obtained by using the initial conditions. The solution is extended to the whole domain of interest by using the boundary conditions, and a recursive mapping is found for the solution in the second and higher groups of sub-domains. The least upper bound of the displacement of the freely vibrating string is obtained for an arbitrary movement profile. The forced response of the string with non-homogeneous boundary conditions is obtained using a transformation method and the direct wave method. A new method is used to derive the rate of change of the vibratory energy of the translating string from the system viewpoint. Three different approaches are used to derive and interpret the rate of change of the vibratory energy of the string within the control volume, and the energy growth mechanism of the string during retraction is elucidated. The solution methods are applied to a moving elevator cable with variable length. An interesting parametric instability phenomenon in a translating string with sinusoidally varying length is discovered.
APA, Harvard, Vancouver, ISO, and other styles
4

Liu, Chuan-He, and Ting-Li Yang. "The Topological Structure Code Permutation Group Method of Polyhedral Solid for Identification of Kinematic Chains Isomorphism." In ASME 1998 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/detc98/mech-5915.

Full text
Abstract:
Abstract This paper puts forward a new method for identification of kinematic chains isomorphism, which is called the topological structure code permutation group method of polyhedral solid. It can be put into practice by means of computer, and it is exact, dependable, quick and efficient. When isomorphism of two kinematic chains is identified by the method, it only need determine whether one permutation can be found out or not between topological structure codes of the two kinematic chains, or determine whether adjoint codes of the two topological structure codes are equal or not, it need not find out a symmetry group at all. It applies to all kinds of non-separable closed kinematic chains that don’t contain compound hinges. In this paper, a new concept called polyhedral solid is put forward, the polyhedral solid model is given, and a theorem that describes the relation of faces, vertices, edges and geometric solids of a connected graph is given and proved. This paper expounds the definitions and general forms of the topological structure code and its adjoint code, the methods and rules of coding, the procedure of generating them. It also expounds and proves the beingness, accuracy and the uniqueness of the topological structure code and its adjoint code and the necessary and sufficient condition and criteria of kinematic chains isomorphism as well. The algorithm and some typical examples for identification of kinematic chains isomorphism are given.
APA, Harvard, Vancouver, ISO, and other styles
5

Gu, Bin, Xingwang Ju, Xiang Li, and Guansheng Zheng. "Faster Training Algorithms for Structured Sparsity-Inducing Norm." In Twenty-Seventh International Joint Conference on Artificial Intelligence {IJCAI-18}. California: International Joint Conferences on Artificial Intelligence Organization, 2018. http://dx.doi.org/10.24963/ijcai.2018/299.

Full text
Abstract:
Structured-sparsity regularization is popular for sparse learning because of its flexibility of encoding the feature structures. This paper considers a generalized version of structured-sparsity regularization (especially for $l_1/l_{\infty}$ norm) with arbitrary group overlap. Due to the group overlap, it is time-consuming to solve the associated proximal operator. Although Mairal~\shortcite{mairal2010network} have proposed a network-flow algorithm to solve the proximal operator, it is still time-consuming especially in the high-dimensional setting. To address this challenge, in this paper, we have developed a more efficient solution for $l_1/l_{\infty}$ group lasso with arbitrary group overlap using an Inexact Proximal-Gradient method. In each iteration, our algorithm only requires to calculate an inexact solution to the proximal sub-problem, which can be done efficiently. On the theoretic side, the proposed algorithm enjoys the same global convergence rate as the exact proximal methods. Experiments demonstrate that our algorithm is much more efficient than network-flow algorithm, while retaining the similar generalization performance.
APA, Harvard, Vancouver, ISO, and other styles
6

Kim, Ho-Wuk, and Sang-Kwon Lee. "Locating Impact on Thick Plates by Acoustic Wave Analysis." In ASME 2008 9th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2008. http://dx.doi.org/10.1115/esda2008-59508.

Full text
Abstract:
Loose parts in a steam generator of a nuclear power plant often impact the wall of the generator and become one of the damage sources in the nuclear power plant. In general, the steam generator of the nuclear power plant is structured by thick plates. This paper presents a novel approach to locating an impact load in a thick plate. The approach is based on an analysis of the acoustic waveforms measured by a sensor array located on the plate surface and theoretically obtained by either the exact elastodynamic or theory the approximate shear deformation plate theory (SDPT). For accurate estimation of the location of the impact source due to loose part, the time differences in the arrival times of the waves at the sensors and their propagation velocities are determined. This is accomplished through the use of a combined higher order time frequency (CHOTF) method, which is capable of detecting signals with lower signal to noise ratio compared to other available methods. The dispersion curves for multi modes of Lamb waves are calculated by using exact plate theory and SDPT. It is difficult to measure directly the group velocity for Lamb mode of acoustic waveform in the thick plate because they are dispersive waves. However, most of the energy in the wave is carried by the flexural waves (A0 mode); the group velocity of this mode is extracted by using the CHOTF technique for estimating the impact source location. The estimates are shown to be in excellent agreement with the actual locations and the technique is applied to the detection of the location of the impact load due to the loose part in a nuclear power plant.
APA, Harvard, Vancouver, ISO, and other styles
7

Molina, Oscar, Laura Santos, Francisco Herrero, Agustin Monaco, and Darren Schultz. "Is Decline Curve Analysis the Right Tool for Production Forecasting in Unconventional Reservoirs?" In SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206152-ms.

Full text
Abstract:
Abstract This study presents a novel metaheuristic algorithm that uses a physics-based model for multi-fractured horizontal wells (MFHW) to accurately predict the estimated ultimate recovery (EUR) for unconventional reservoirs. The metaheuristic algorithm creates a sizeable number of stochastic simulations and keeps the simulation results from those random models that closely reproduce observed production data. Unlike other optimization methods, the proposed algorithm does not aim at finding the exact solution to the problem but a group of sufficiently accurate solutions that help to construct the partial solution to the optimization problem as a function of production history. Results from this work provide sufficient evidence as to why traditional decline curve analysis (DCA) is not a suitable solution for production forecasting in unconventional reservoirs. Two case studies are discussed in this work where results from both modeling strategies are compared. Evolutionary prediction of EUR over time using DCA behaves erratically, regardless of the amount of historical production data available to the regression model. Such erratic behavior can, in turn, yield an erroneous estimation of key economic performance indicators of an asset. In contrast, the proposed metaheuristic algorithm delivers precise and accurate results consistently, achieving a significant reduction of uncertainties as more production data becomes available. In conclusion, the proposed partial optimization approach enables the accurate calculation of important metrics for unconventional reservoirs, including production forecasting and expected productive life of an asset.
APA, Harvard, Vancouver, ISO, and other styles
8

Romdhane, Lofti. "A Dyad Search Algorithm for Solving Planar Linkages Using the Dyad Method." In ASME 1992 Design Technical Conferences. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/detc1992-0276.

Full text
Abstract:
Abstract Based on graph representation of planar linkages, a new algorithm was developed to identify the different dyads of a mechanism. A dyad or class II group, is composed of two binary links connected by either a revolute (1) or a slider (0) pair with provision for attachment to other links by lower pair connectors located at the end of each link. There are five types of dyads: the D111, D101, D011, D001, and D010. The dyad analysis of a mechanism is predicated on the ability to construct the system from one or more of the five binary structure groups or class II groups. If the mechanism is complicated and several dyads are involved, the task of identifying these dyads by inspection could be difficult and time consuming for the user. This algorithm allows a complete automation of this task. This algorithm is based on the Dijkstra’s algorithm, for finding the shortest path in a graph, and it is used to develop a computer program, called KAMEL: Kinematic Analysis of MEchanical Linkages, and implemented on an IBM-PC PS/2 model 80. When compared to algorithmic methods, like the Newton-Raphson, the dyad method proved to be a very efficient one and requires as little as one tenth of the time needed by the method using Newton-Raphson algorithm. Moreover, the dyad method yields the exact solution of the position analysis and no initial estimates are needed to start the analysis. This method is also insensitive to the value of the step-size crank rotation, therefore, allowing a very accurate and fast solution of the mechanism at any position of the input link.
APA, Harvard, Vancouver, ISO, and other styles
9

Mathew, Shilu M., Malak Ibrahim, Asmaa Al Thani, Khalid Al Ansari, Hassan Zaraket, and Hadi M. Yassine. "Antigenica and Genetic Characterization of Identified Rotavirus Strains in Qatar in Response to Rotarix Vaccine Usage." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0114.

Full text
Abstract:
To identify genetic and antigenic variation in RV in response to vaccine usage. Methods: A total of 231 RV-positive fecal samples were collected from children suffering from AGE during three-year study period between June 2016 and June 2019. The age of the subjects ranged between 2 months and 14 years (median of 16 months). RV genotyping and neutralizing regions, which include both VP4 (Ptype) and VP7 (G type), were amplified and sequenced. We characterized amino acid sequence variability and predicted antigenicity compared to the Rotarix vaccine strain. Phylogenetic analyses were performed using MEGA7.0. Fisher’s exact test was used to run the statistical analysis for the clinical and demographical characteristics of circulating strains. Results: RV infection was most common in children between 3-36 months of age. Among the RV-positive cases, 135 (59.3%) had been vaccinated using either of the RV vaccines available. The number of children vaccinated with one and two-dose was 53 (39.2%) and 82 (60.8%), respectively. The percentage reduction of disease in a vaccinated group of pediatrics compared to an unvaccinated group of pediatrics was 25%. Of these, 108 (78.2%) experienced diarrhea for less than three days, and only eight (6.7%) had diarrhea for more than five days. All vaccinated children showed mild to moderate dehydration except for ten children who were then treated with intravenous fluids. G3 strains were the most strains detected (40%) followed by G2 (17.7%), G4 (16.8%), G9 (15%), G1 (9%), and G8 (0.9%). The dominant RV strains during the study period were G3P [8] (30.8%), G2P [8] (12.3%), G4P [8] (11.7%) and G1P[8] (10.4%). Comparisons of the amino acid residues defining the VP7 and VP4 antigenic domains revealed several mismatches between G1P [8] strains and the G1 and P [8] strains contained in the currently licensed rotavirus vaccines Rotarix. Eighty percent (n=8) of the G1 genotype specimens harbored three amino acid substitutions (N94S, S123N, and M217T) in 7‐ 1a and 7‐ 2b antigenic sites in comparison to the Rotarix vaccine. The P [8] strains with G4 and G9 counterparts showed the highest degree of variation among all specimens with known G genotype. These viruses had 15 and 13 substitutions in their VP4 antigenic epitopes when compared with the P [8] component of the Rotarix vaccines. Conclusion: This study suggests genetic variability in G1 genotype specimens to escape the vaccine-derived immune response. It also identified the wide diversity of circulating RV genotypes in Qatar.
APA, Harvard, Vancouver, ISO, and other styles
10

Changizi, M. Amin, Ali Abolfathi, and Ion Stiharu. "MEMS Wind Speed Sensor: Large Deflection of Curved Micro-Cantilever Beam Under Uniform Horizontal Force." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50560.

Full text
Abstract:
Micro-cantilever beams are currently employed as sensor in various fields. Of main applications, is using such beams in wind speed sensors. For this purpose, curved out of plane micro-cantilever beams are used. Uniform pressure on such beams causes a large deflection of beam. General mechanics of material theory deals with small deflection and thus cannot be used for explaining this deflection. Although there are a body of works on analysing of large deflection [1], nonlinear deflection, of curved beams [2], yet there is no research on large deflection of curved beam under horizontal uniform distributed force. Theoretically, the wind force is applying horizontally on curved micro-cantilever beam. Here, we neglect the effect of moving weather from beam sides. We first aim how to drive the governed equation. A curved beam does not have a calculable centroid. Also large deflection of beam changes its curvature which would change the centroid of beam consciously. The variation of centroid makes very though calculating the bending moment of each cross section in the beam. To address this issue, an integral equation will be used. The total force will be considered as a single force applied at the centroid. The second challenge is solving the governed nonlinear ordinary differential equation (ODE). Although there are several methods to solve analytically nonlinear ODE, Lie symmetry method, with all its complication, is a general method for this kind of equations. This approach covers all current methods in analytical solving nonlinear ODEs. In this method, an infinitesimal transformation should be calculated. All transformations under one parameter creates a group that called Lie group. A value of parameter which transfers the equation onto itself is called invariant of ODE. One can calculate canonical coordinates ODEs by the invariant. Solving the canonical coordinates ODEs yields to calculating the canonical coordinates. Canonical coordinate are used to reduce the order of nonlinear ODE [3]. By repeating this method one can solve high order ODEs. Our last question is how to do numerical solution of ODE. The possible answer will help to explain the phenomena of deflection clearly and compare the analytical solution with numerical results. Small dimensions of beam, small values of applied force from one side and Young modules value from the other side, will create a stiff ODE. Authors experience in this area shows that the best method to sole these kind of equations is LSODE. This method can be used in Maple. Here, primary calculations show that the governed equation is second order nonlinear ODE and we propose two possible invariants to solve ODE. Overall, the primary numerical solution has shown perfect match with the exact solution.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Exact Renomalization Group Methods' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography