Relevant bibliographies by topics / Tensor Field Generation

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

Academic literature on the topic 'Tensor Field Generation'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Tensor Field Generation"

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Filho, L. Gonzaga, M. S. Cunha, and R. R. Landim. "Topological mass generation to antisymmetric tensor matter field." Europhysics Letters (EPL) 69, no. 2 (January 2005): 184–88. http://dx.doi.org/10.1209/epl/i2004-10336-9.

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Hardhienata, Hendradi, Tony Ibnu Sumaryada, Benedikt Pesendorfer, and Adalberto Alejo-Molina. "Bond Model of Second- and Third-Harmonic Generation in Body- and Face-Centered Crystal Structures." Advances in Materials Science and Engineering 2018 (September 23, 2018): 1–11. http://dx.doi.org/10.1155/2018/7153247.

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In this work, we describe the third- and fourth-rank tensors of body- and face-centered cubic systems and derive the s- and p-polarized SHG far field using the simplified bond-hyperpolarizability model. We also briefly discuss bulk nonlinear sources in such structures: quadrupole contribution, spatial dispersion, electric-field second-harmonic generation, and third-harmonic generation, deriving the corresponding fourth rank tensor. We show that all the third- and fourth-rank tensorial elements require only one independent fitting parameter.
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Chen, Yongshuai, Eugene Zhang, and Harry Yeh. "Laboratory experiments on counter-propagating collisions of solitary waves. Part 2. Flow field." Journal of Fluid Mechanics 755 (August 19, 2014): 463–84. http://dx.doi.org/10.1017/jfm.2014.427.

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AbstractIn the companion paper (Chen & Yeh, J. Fluid Mech., vol. 749, 2014, pp. 577–596), collisions of counter-propagating solitary waves were studied experimentally by analysing the measured water-surface variations. Here we study the flow fields associated with the collisions. With the resolved velocity data obtained in the laboratory, the flow fields are analysed in terms of acceleration, vorticity, and velocity-gradient tensors in addition to the velocity field. The data show that flow acceleration becomes maximum slightly before and after the collision peak, not in accord with the linear theory which predicts the maximum acceleration at the collision peak. Visualized velocity-gradient-tensor fields show that fluid parcels are stretched vertically prior to reaching the state of maximum wave amplitude. After the collision peak, fluid parcels are stretched in the horizontal direction. The boundary-layer evolution based on the vorticity generation and diffusion processes are discussed. It is shown that flow separation occurs at the bed during the collision. The collision creates small dispersive trailing waves. The formation of the trailing waves is captured by observing the transition behaviour of the velocity-gradient-tensor field: the direction of stretching of fluid parcels alternates during the generation of the trailing waves.
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BUCHEL, A., F. A. CHISHTIE, M. T. HANIF, S. HOMAYOUNI, JUNJI JIA, and D. G. C. McKEON. "RADIATIVE CORRECTIONS IN VECTOR-TENSOR MODELS." International Journal of Modern Physics A 25, no. 01 (January 10, 2010): 163–69. http://dx.doi.org/10.1142/s0217751x10047804.

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We consider a two-form antisymmetric tensor field ϕ minimally coupled to a non-Abelian vector field with a field strength F. Canonical analysis suggests that a pseudoscalar mass term [Formula: see text] for the tensor field eliminates degrees of freedom associated with this field. Explicit one-loop calculations show that an additional coupling m Tr (ϕ ∧ F) (which can be eliminated classically by a tensor field shift) reintroduces tensor field degrees of freedom. We attribute this to the lack of the renormalizability in our vector-tensor model. We also explore a vector-tensor model with a tensor field scalar mass term [Formula: see text] and coupling m Tr (ϕ ∧ ⋆F). We comment on the Stueckelberg mechanism for mass generation in the Abelian version of the latter model.
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Nazari, Elham, and Mahmood Roshan. "Gravitational radiation by magnetic field: application to millisecond magnetars." Monthly Notices of the Royal Astronomical Society 498, no. 1 (August 11, 2020): 110–27. http://dx.doi.org/10.1093/mnras/staa2322.

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ABSTRACT We investigate the direct contribution of the magnetic field to the gravitational wave (GW) generation. To do so, we study the post-Newtonian (PN) energy–momentum tensor of the magnetized fluid and the PN expansion of the gravitational potential in the wave zone. We show that the magnetic field appears even in the first PN order of the multipole moment tensor. Then, we find an explicit relativistic correction containing the magnetic field contribution to the well-known quadrupole formula. As an application of this derivation, we find that the B-field part of the GWs released in the early stages of a millisecond magnetar’s life can be as much as one-hundredth of the signals due to the deformed rotating neutron stars. We show that although the event rate of this system is small, the signal would lie in the sensitivity range of the next generation of detectors.
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Yushkov, E. V., R. Allahverdiyev, and D. D. Sokoloff. "Mean-Field Dynamo Model in Anisotropic Uniform Turbulent Flow with Short-Time Correlations." Galaxies 8, no. 3 (September 19, 2020): 68. http://dx.doi.org/10.3390/galaxies8030068.

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The mean-field model is one of the basic models of the dynamo theory, which describes the magnetic field generation in a turbulent astrophysical plasma. The first mean-field equations were obtained by Steenbeck, Krause and Rädler for two-scale turbulence under isotropy and uniformity assumptions. In this article we develop the path integral approach to obtain mean-field equations for a short-correlated random velocity field in anisotropic streams. By this model we analyse effects of anisotropy and show the relation between dynamo growth and anisotropic tensors of helicity/turbulent diffusivity. Considering particular examples and comparing results with isotropic cases we demonstrate several mean-field effects: super-exponential growth at initial times, complex dependence of harmonics growth on the helicity tensor structure, when generation is possible for near-zero component or near-zero helicity trace, increase of the averaged magnetic field inclined to the initial current density that leads to effective Lorentz back-reaction and violation of force-free conditions.
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KOCHLOUKOVA, DESSISLAVA H. "Finite generation of exterior and symmetric powers." Mathematical Proceedings of the Cambridge Philosophical Society 125, no. 1 (January 1999): 21–29. http://dx.doi.org/10.1017/s0305004198002874.

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If Q is a finitely generated abelian group, k a field, V a finitely generated kQ-module Bieri and Groves have proved that [otimes ]mV is a finitely generated as a kQ-module with diagonal Q-action if and only if ∧iV is finitely generated as a kQ-module for all 1[les ]i[les ]m. We generalize this result by showing that if the mth exterior power of V or the mth symmetric power of V is finitely generated as a kQ-module so is the mth tensor power of V. Further we show the equivalence between the finite generation of symmetric and tensor powers in the case when the ground ring is a PID of characteristic 0.
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ALLEN, THEODORE J., MARK J. BOWICK, and AMITABHA LAHIRI. "TOPOLOGICAL MASS GENERATION IN 3+1 DIMENSIONS." Modern Physics Letters A 06, no. 07 (March 7, 1991): 559–71. http://dx.doi.org/10.1142/s0217732391000580.

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The 4-dimensional theory of a 1-form Abelian gauge field A coupled to a 2-form (antisymmetric tensor) potential B is studied. The two gauge invariances of the theory admit a coupling mB ∧ F where F is the field strength (F=dA) of A. It is shown that this theory is a unitary, renormalizable theory of a massive spin-one field with no additional degrees of freedom. In this sense, it is a generalization to four dimensions of topological mechanisms in two dimensions (the Schwinger model) and three dimensions (Chern-Simons theory). The issue of spontaneous symmetry breaking is also examined.
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Bamba, Kazuharu. "Large-scale magnetic fields, non-Gaussianity, and gravitational waves from inflation." International Journal of Modern Physics A 32, no. 36 (December 30, 2017): 1747021. http://dx.doi.org/10.1142/s0217751x17470212.

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We explore the generation of large-scale magnetic fields in the so-called moduli inflation. The hypercharge electromagnetic fields couple to not only a scalar field but also a pseudoscalar one, so that the conformal invariance of the hypercharge electromagnetic fields can be broken. We explicitly analyze the strength of the magnetic fields on the Hubble horizon scale at the present time, the local non-Gaussianity of the curvature perturbations originating from the massive gauge fields, and the tensor-to-scalar ratio of the density perturbations. As a consequence, we find that the local non-Gaussianity and the tensor-to-scalar ratio are compatible with the recent Planck results.
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Hirose, Chiaki, Naotoshi Akamatsu, and Kazunari Domen. "Formulas for the Analysis of the Surface SFG Spectrum and Transformation Coefficients of Cartesian SFG Tensor Components." Applied Spectroscopy 46, no. 6 (June 1992): 1051–72. http://dx.doi.org/10.1366/0003702924124385.

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Comprehensive expressions have been presented to facilitate the analysis of the surface sum-frequency generation (SFG) spectrum. The electric field components of the SFG beam for a given experimental setup have been related via appropriately defined Fresnel coefficients to the nonlinear source polarization, which in turn has been related to the electric fields of exciting visible and infrared beams through the macroscopic SFG susceptibility tensor. The coefficients of transformation have been given to relate the laboratory-fixed Cartesian components of the SFG tensor to the components described in a surface-fixed axis system. The tensor components have been further related to the components of the microscopic hyperpolarizability tensor of surface species, and the explicit expressions (in terms of the Euler angles defining molecular orientation) of the transformation coefficients are presented to describe the Cartesian tensor components described in a surface-fixed axis system by the molecule-fixed components.
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Dissertations / Theses on the topic "Tensor Field Generation"

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Andrade, Diego Fernando. "Patterning and Customization: Evaluating Tensor Field Generation For Mechanical Design On Free-Form Surfaces." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/889.

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This dissertation delivers a new computational framework for the automatic generation of geometric feature patterns for industrial design and architectural facades on free-form surfaces. Such patterns include holes in a speaker grill, showerhead holes, protrusions on ceramics or bumpy textures on a panel. These patterns play a key role in making a designed object aesthetically pleasing as well as functional. Computer Aided Design (CAD) systems currently offer tools for generating simple patterns, such as uniformly spaced rectangular or radial patterns. However, they are not applicable to more general cases required in industrial design, including arbitrarily shaped target geometry and graded feature sizes. These tools are limited in several ways: (1) They cannot be applied to free-form geometries used in industrial design, (2) Patterning of these features happens within a single working plane and is not applicable to highly curved surfaces, and (3) Created features lack anisotropy and spatial variations, such as changes in the size and orientation of geometric features within a given region. This thesis proposes a new method of taking input for a target region along with sizing metrics. It will generate feature patterns automatically in three steps: (1) packing isotropic or anisotropic cells tightly in a target region, (2) scaling features according to the specified sizing metrics, and (3) adding features on the base geometry. This approach automatically generates complex patterns that conform to the boundary of any specified region. User input of a small number of geometric features (called “seed features”) of desired size and orientation in preferred locations also can be specified within the target domain. These geometric seed features are then transformed into tensors and used as boundary conditions to generate a Riemannian metric tensor field. A form of the Laplace heat equation is used to generate the field over the target domain, subject to specified boundary conditions. The field represents the anisotropic pattern of the geometric features. The system is implemented as a plugin module in a commercial CAD package to add geometric features to the target region of the model using two set operations, union and subtraction. This method facilitates the creation of a complex pattern of hundreds of geometric features in minutes. All the features are accessible from the CAD system and can be manipulated individually if required by the user. This allows the industrial designer or architect to explore more alternatives by avoiding the tedious and time-consuming manual generation of these geometric patterns.
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Filho, LuÃs Gonzaga Rodrigues. "Abelian and non-abelian tensor matter fields: Mass generation and duality." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=787.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
In this Thesis we analyze the generation of mass to the antisymmetric tensor matter field in a non-Abelian model and the mapping of the antisymmetric matter field to the antisymmetric tensor gauge field in the Abelian case. For the mass generation, we use two different mechanisms. The first one is the spontaneous symmetry breaking, where we use scalar fields with nonzero expected vacuum value in the SU(N) representation. Besides the massive term for the matter field, by relaxing the requirement of parity invariance we obtain topological terms. The second mechanism is denominated topological mass generation. It consists by introducing in the action of a vectorial complex field and a massive topological coupling term between ectorial complex and complex selfdual field. Direct calculation of the Feynman propagators show us that the matter field has a massive pole. In dual mapping, we can say that the $U(1)$ invariant action of the matter field is mapped in a dual action described by the antisymmetric tensor gauge field and a topologically conserved current. Two remarkable characteristics can be observed in this mapping: the first one is the parity preservation due to topological terms in the both dual actions; the second characteristic is that, though the conserved current admits topological terms, the mapping is free of axial anomalies. The presence of anomalies prevents the conservation of topological currents in a mapping such as bosonization in 4 dimensions. One of the most important requisites for the renormalizability of a theory in all orders of h is that the theory must be free of anomalies.
Nesta tese analisaremos a geraÃÃo de massa para o campo tensorial anti-simÃtrico de matÃria no modelo de gauge nÃo-abeliano e o mapeamento, no caso abeliano, entre o campo tensorial anti-simÃtrico de matÃria e o campo tensorial anti-simÃtrico de gauge Com relaÃÃo à geraÃÃo de massa, utilizam-se dois mecanismos: O primeiro, denominado quebra espontÃnea de simetria, consiste em acoplarmos ao modelo campos escalares, com valores esperados no vÃcuo nÃo-nulos, descritos no modelo de Higgs com simetria de Gauge nÃo-abeliana. AlÃm do termo massivo para o referido campo, obtÃm-se tambÃm termos topolÃgicos como resultado da quebra de paridade existente no modelo. O segundo, denominado geraÃÃo de massa topolÃgica, à obtido a partir da inclusÃo na aÃÃo de um campo vetorial complexo com um termo de acoplamento, incluindo-se um termo topolÃgicos entre os campos de matÃria e vetorial. O cÃlculo dos propagadores de feynman nos revela que o campo de matÃria adquiri pÃlo massivo. Quanto ao mapeamento dual podemos afirmar que a aÃÃo correspondente ao campo de matÃria com uma corrente conservada U(1) à mapeada em uma aÃÃo dual com o campo tensorial anti-simÃtrico de gauge e uma corrente topolÃgica identicamente conservada. Duas caracterÃsticas podem ser observadas nesse mapeamento: A primeira à que ele preserva a simetria de paridade existente, em virtude da corrente conservada na teoria original possuir termos topolÃgicos. O segundo à que, embora a corrente conservada admita termos topolÃgicos, o mapeamento à livre de anomalias. A presenÃa dessas anomalias impede a conservaÃÃo da corrente topolÃgica no modelo dual. AlÃm disso um dos requisitos para que uma teoria seja renormalizÃvel, à que a teoria seja livre de anomalias
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Books on the topic "Tensor Field Generation"

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Maggiore, Michele. Inflation and primordial perturbations. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198570899.003.0012.

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Review of inflationary cosmology. Single-field slow-roll inflation. Large-field inflation and small-field inflation. Starobinsky model. Quantum field theory in curved space. Generation of primordial perturbations during inflation. Mukhanov-Sasaki equation. Scalar and tensor perturbations.
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Sakas, William. Computational Approaches to Parameter Setting in Generative Linguistics. Edited by Jeffrey L. Lidz, William Snyder, and Joe Pater. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780199601264.013.29.

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This article presents a non-exhaustive history of research that employs computational modeling of human language acquisition in Chomsky’s principles and parameters framework. The history underscores a tension that has evolved in the field between deterministic (triggering) and nondeterministic (search) approaches. Though it is now clear that the original and widely accepted conception of triggering was flawed, results from recent computational modeling efforts indicate that a modified deterministic triggering theory of human language acquisition may be viable after all.
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Maggiore, Michele. Gravitational Waves. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198570899.001.0001.

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A comprehensive and detailed account of the physics of gravitational waves and their role in astrophysics and cosmology. The part on astrophysical sources of gravitational waves includes chapters on GWs from supernovae, neutron stars (neutron star normal modes, CFS instability, r-modes), black-hole perturbation theory (Regge-Wheeler and Zerilli equations, Teukoslky equation for rotating BHs, quasi-normal modes) coalescing compact binaries (effective one-body formalism, numerical relativity), discovery of gravitational waves at the advanced LIGO interferometers (discoveries of GW150914, GW151226, tests of general relativity, astrophysical implications), supermassive black holes (supermassive black-hole binaries, EMRI, relevance for LISA and pulsar timing arrays). The part on gravitational waves and cosmology include discussions of FRW cosmology, cosmological perturbation theory (helicity decomposition, scalar and tensor perturbations, Bardeen variables, power spectra, transfer functions for scalar and tensor modes), the effects of GWs on the Cosmic Microwave Background (ISW effect, CMB polarization, E and B modes), inflation (amplification of vacuum fluctuations, quantum fields in curved space, generation of scalar and tensor perturbations, Mukhanov-Sasaki equation,reheating, preheating), stochastic backgrounds of cosmological origin (phase transitions, cosmic strings, alternatives to inflation, bounds on primordial GWs) and search of stochastic backgrounds with Pulsar Timing Arrays (PTA).
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Avril, Emmanuelle, and Yann Béliard, eds. Labour united and divided from the 1830s to the present. Manchester University Press, 2018. http://dx.doi.org/10.7228/manchester/9781526126320.001.0001.

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Spanning a period which stretches from the 19th century to the present day, this book takes a novel look at the British labour movement by examining the interaction between trade unions, the Labour Party, other parties of the Left, and other groups such as the Co-op movement and the wider working class, to highlight the dialectic nature of these relationships, marked by consensus and dissention. It shows that, although perceived as a source of weakness, those inner conflicts have also been a source of creative tension, at times generating significant breakthroughs. This book seeks to renew and expand the field of British labour studies, setting out new avenues for research so as to widen the audience and academic interest in the field, in a context which makes the revisiting of past struggles and dilemmas more pressing than ever. The book together brings well-established labour historians and political scientists, thus establishing dialogue across disciplines, and younger colleagues who are contributing to the renewal of the field. It provides a range of case studies as well as more wide-ranging assessments of recent trends in labour organising, and will therefore be of interest to academics and students of history and politics, as well as to practitioners, in the British Isles and beyond.
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Croasmun, Matthew. Emergence. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190277987.003.0003.

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Emergence theory in philosophy of science is introduced, first in modest terms of the emergent properties exhibited by complex wholes that are not exhibited by their constituent parts. Then, emergence is treated as a trans-ordinal theory that stakes out a middle ground between reductionism and dualism. The tension between supervenience and downward causation is described as the generative dialectic of emergence. The coherence of downward causation is debated and ultimately affirmed on account of the prevalence of downward causation in the sorts of accounts produced by fields like systems biology. Racism is treated as a case study of the sorts of causal feedback loops generated by complex causal structures that operate at multiple levels of hierarchy.
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Livermore, Roy. All at Sea. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198717867.003.0009.

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According to first-generation plate tectonics, sea-floor spreading was nice and simple. Plates were pulled apart at mid-ocean ridges, and weak mantle rocks rose to fill the gap and began to melt. The resulting basaltic magma ascended into the crust, where it ponded to form linear ‘infinite onion’ magma chambers beneath the mid-ocean tennis-ball seam. At frequent intervals, vertical sheets of magma rose from these chambers to the surface, where they erupted to form new ocean floor or solidified to form dykes, in the process acquiring a magnetization corresponding to the geomagnetic field at the time. Mid-ocean ridge axes were defined by rifted valleys and divided into segments by transform faults with offsets of tens to hundreds of kilometres, resulting in the staircase pattern seen on maps of the ocean floor. All mid-ocean ridges were thus essentially identical. Such a neat and elegant theory was bound to be undermined as new data were acquired in the oceans.
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Aarts, Bas, Jill Bowie, and Gergana Popova, eds. The Oxford Handbook of English Grammar. Oxford University Press, 2019. http://dx.doi.org/10.1093/oxfordhb/9780198755104.001.0001.

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This handbook provides an authoritative, critical survey of current research and knowledge in the grammar of the English language. Following an introduction from the editors, the volume’s expert contributors explore a range of core topics in English grammar, beginning with issues in grammar writing and methodology. Chapters in part II then examine the various theoretical approaches to grammar, such as cognitive, constructional, and generative approaches, followed by the chapters in part III, which comprehensively cover the different subdomains of grammar, including compounds, phrase structure, clause types, tense and aspect, and information structure. Part IV offers coverage of the relationship between grammar and other fields – lexis, phonology, meaning, and discourse – while the concluding part of the book investigates grammatical change over time, regional variation, and genre and literary variation.
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Book chapters on the topic "Tensor Field Generation"

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Bi, Chongke, Daisuke Sakurai, Shigeo Takahashi, and Kenji Ono. "Interactive Control of Mesh Topology in Quadrilateral Mesh Generation Based on 2D Tensor Fields." In Advances in Visual Computing, 726–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-33191-6_72.

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Smith, Jarrod L., Veli-Tapani Kuokkala, Jeremy D. Seidt, and Amos Gilat. "Internal Heat Generation in Tension Tests of AISI 316 Using Full-Field Temperature and Strain Measurements." In Advancement of Optical Methods in Experimental Mechanics, Volume 3, 97–103. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-63028-1_16.

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Guilleminot, J., and C. Soize. "Generation of non-Gaussian tensor-valued random fields using an ISDE-based algorithm." In Safety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures, 2793–98. CRC Press, 2014. http://dx.doi.org/10.1201/b16387-404.

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Zinn-Justin, Jean. "Dimensional continuation, regularization, minimal subtraction (MS). Renormalization group (RG) functions." In Quantum Field Theory and Critical Phenomena, 220–39. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0010.

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In this chapter, the notions of dimensional continuation and dimensional regularization are introduced, by defining a continuation of Feynman diagrams to analytic functions of the space dimension. Dimensional continuation, which is essential for generating Wilson–Fisher's famous ϵexpansion in the theory of critical phenomena, and dimensional regularization seem to have no meaning outside the perturbative expansion of quantum field theory (QFT). Dimensional regularization is a powerful regularization technique, which is often used, when applicable because it leads to much simpler perturbative calculations. Dimensional regularization performs a partial renormalization, cancelling what would show up as power-law divergences in momentum or lattice regularization. In particular it cancels the commutator of quantum operators in local QFTs. These cancellations may be convenient but may also, occasionally, remove divergences that have an important physical meaning. It is not applicable when some essential property of the field theory is specific to the initial dimension. For example, in even space dimensions, the relation between γS (identical to γ5 in four dimensions) and the other γ matrices involving the completely antisymmetric tensor ϵμ1···μd, may be needed in theories violating parity symmetry. Its use requires some care in massless theories because its rules may lead to unwanted cancellations between ultraviolet and infrared logarithmic divergences. Explicit calculations at two-loop order in a scalar QFT with a general four-field interaction are performed.
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Krasnoholovets, Volodymyr. "A Theoretical Study of the Refractive Index of KDP Crystal Doped with TiO2 Nanoparticles." In Sustainable Nanosystems Development, Properties, and Applications, 524–34. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0492-4.ch013.

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In the present chapter we study a nonlinear response of an optical matrix formed by the K2HPO4 crystal doped with TiO2 nanoparticles. Such doped matrix is a nonlinear optical system that is characterized by the cubic non-linear optical response at picosecond laser pulses. Laser pulses release photoelectrons from nanoparticles, which emerge as free carriers on the nanoparticles' surface generating an electric field in local area of the K2HPO4 matrix, which results in the phase transition from the paraphase to the ferroelectric phase state. The appeared ferroelectric phase induces a large polarization around TiO2 nanoparticles, which in turn immediately produces a nonlinear optical response to the laser pulse of the inverse sign, such that the laser beam becomes more focused. The gigantic non-linear susceptibility ??(3) responsible for the phenomenon of focusing of the laser beam is calculated by using the pseudospin model for the description of ferroelectric crystals and the expressions for nonlinear-susceptibility tensor components computed by other researchers.
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Constantine, Mary-Ann, and Gerald Porter. "Sea-changes: minimal texts as regenerative forms." In Fragments and Meaning in Traditional Song. British Academy, 2003. http://dx.doi.org/10.5871/bacad/9780197262887.003.0005.

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This chapter discusses minimal texts as regenerative forms. It attempts to show that short and fragmented song-forms have played a crucial part in some of the most stimulating approaches to the process of song variation. The various processes in ballads, including ‘floating’ verses and a ‘tension of essences’ are discussed as well. The chapter also shows the complexity of the processes of oral transmission and the smallness of the units that are capable of evoking stories and of generating rather strong emotional fields.
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Phan-Thien, Nhan, and Sangtae Kim. "Completed Double Layer Boundary Element Method." In Microstructures in Elastic Media. Oxford University Press, 1994. http://dx.doi.org/10.1093/oso/9780195090864.003.0007.

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Despite the linearity of the Navier equations, solutions to complex boundaryvalue problems require substantial computing resources, especially in the so-called exterior problems, where the deformation field in the space between the inclusions to infinity must be calculated. In the traditional spatial methods, such as finite difference, finite element, or finite volume, this space must be discretized, perhaps with the help of "infinite" elements or a truncation scheme at a finite but large distance from the inclusions (Beer and Watson, Zienkiewicz and Morgan). There are two important limitations of spatial methods. The first is the mesh generation problem. To be numerically efficient, we must use unstructured mesh and concentrate our effort on where it is needed. Efficient two-dimensional, unstructured, automatic mesh generation schemes exist-one good example is Jin and Wiberg-but unstructured three-dimensional mesh generation is still an active area of research. The second limitation is much more severe: even a moderately complicated problem requires the use of supercomputers (e.g., Graham et al.). Since we are concerned with the large-scaled simulations of particulate composites, with the aim of furnishing constitutive information for modeling purposes, our system will possibly have tens of thousands of particles, and therefore the spatial methods are out of the question. We have seen how the deformation field can be represented by a boundary integral equations, either by a direct method, which deals directly with primitive variables (displacement and trciction) on the surface of the domain, or by the indirect method, where the unknowns are the fictitious densities on the surface of the domain. When the field point is allowed to reside on the surface of the domain, then a set of boundary integral equations results that relates only to the variables on the boundary (displacement and traction, or fictitious densities), and this is the basis of the boundary element method. The boundary is then discretized, and the integrals are evaluated by suitable quadratures; this then leads to a set of algebraic equations to be solved for the unknown surface variables.
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Venkatsubramanyan, Shailaja. "Streamlining Knowledge Map Construction for an Online Auction House Using Automatic Term Filtering." In Innovations in Logistics and Supply Chain Management Technologies for Dynamic Economies, 336–53. IGI Global, 2012. http://dx.doi.org/10.4018/978-1-4666-0267-0.ch020.

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Organizations are building automated technical support software that can help both consumers and field support engineers with problem resolution. The goal of the automated technical support system is reducing operational cost and increasing customer satisfaction. This paper examines the set of challenges that knowledge engineers face in building automated technical support software. This paper uses a technical services engagement with a major online auction house with tens of millions of users to highlight the challenges and present an automated knowledge map generation technique. The objective of this automated technique was to improve the quality of expressions extracted from documents, which would reduce the burden on knowledge engineers to construct knowledge maps. The technique was run on large corpora of documents in the online auction house and found a significant increase in the quality of the knowledge map. Further experimentation showed that the technique works well for other domains as well.
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Neacsu, Ioan, and Anca Cristina Oprea. "Stress and Violence in the Academic Space." In Violence Prevention and Safety Promotion in Higher Education Settings, 50–69. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-2960-6.ch004.

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The study deals with the diversity of the values of the connections that appear between stress and violence in the academic social environment in the context of the research in the field, of the specialized literature, of the psychological and pedagogical semantics and pragmatics. The configuration of the study is a multiple one: definitions and terminological connections, authorities that have roles in the psycho- academic counseling, factors, contexts and risk situations with stress generative potential, behavior with violent potential. It has been identified and examined a rich set of group or psycho individual social, institutional factors, such as group conflicts, asymmetrical interrelationships, motivations of risk, explanatory mechanisms, and situations with reductive, tense release potential. The model of the approach is also defined by methodological- empirical explorations, syntheses, and statistical results which are useful for the community of the university actors. The study ends with proposals and suggestions of analysis and psycho-socio/ pedagogical intervention.
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Ali Syed, Usama, Zareena Kausar, and Neelum Yousaf Sattar. "Control of a Prosthetic Arm Using fNIRS, a Neural-Machine Interface." In Data Acquisition - Recent Advances and Applications in Biomedical Engineering [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93565.

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Development in the field of bio-mechatronics has provided diverse ways to mimic and improve the function of human limbs. Without an elbow joint, the hand remains stiff because all the muscles tension passes through this joint. Advanced myoelectric prosthetic devices are limited due to the lack of appropriate signal sources on residual amputee muscles and insufficient real-time control. Neural-machine interfaces (NMI) are representing a recent approach to develop effective applications. In this research study, an NMI is designed that presents real-time signal processing for command generation. The human brain hemodynamic responses are, therefore, translated into control commands for people suffering from transhumeral amputation. A novel and first of its kind scheme is proposed which utilizes functional near-infrared spectroscopy (fNIRS) to generate the control commands for a three-degree-of-freedom (DOF) prosthetic arm. The time window for fNIRS signals was set to 1 second. The average accuracy was found to be 82% which is a state-of-the-art result for such a technique. The accuracy ranged from 65 to 85% subject-wise. The data were trained and tested on both artificial neural network (ANN) and linear discriminant analysis (LDA). Eight out of 10 motions were correctly predicted in real time by both classifiers.
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Conference papers on the topic "Tensor Field Generation"

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Degen, Shane C., Luis Mejias Alvarez, Jason J. Ford, and Rodney A. Walker. "Tensor Field guidance for time-based waypoint arrival of UAVs by 4D trajectory generation." In 2009 IEEE Aerospace conference. IEEE, 2009. http://dx.doi.org/10.1109/aero.2009.4839605.

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Srivastava, Nitish, Hongbo Rong, Prithayan Barua, Guanyu Feng, Huanqi Cao, Zhiru Zhang, David Albonesi, et al. "T2S-Tensor: Productively Generating High-Performance Spatial Hardware for Dense Tensor Computations." In 2019 IEEE 27th Annual International Symposium on Field-Programmable Custom Computing Machines (FCCM). IEEE, 2019. http://dx.doi.org/10.1109/fccm.2019.00033.

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Pátý, Marek, and Sergio Lavagnoli. "A Novel Vortex Identification Technique Applied to the 3D Flow Field of a High-Pressure Turbine." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90462.

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Abstract The efficiency of modern axial turbomachinery is strongly driven by the secondary flows within the vane or blade passages. The secondary flows are characterized by a complex pattern of vortical structures that origin, interact and dissipate along the turbine gas path. The endwall flows are responsible for the generation of a significant part of the overall turbine loss because of the dissipation of secondary kinetic energy and mixing-out of non-uniform momentum flows. The understanding and analysis of secondary flows requires a reliable vortex identification technique to predict and analyse the impact of specific turbine designs on the turbine performance. However, literature shows a remarkable lack of general methods to detect vortices and to determine the location of their cores and to quantify their strength. This paper presents a novel technique for the identification of vortical structures in a general 3D flow field. The method operates on the local flow field and it is based on a triple decomposition of motion proposed by Kolář. In contrast to a decomposition of velocity gradient into the strain and vorticity tensors, this method considers a third, pure shear component. The subtraction of the pure shear tensor from the velocity gradient remedies the inherent flaw of vorticity-based techniques which cannot distinguish between rigid rotation and shear. The triple decomposition of motion serves to obtain a 3D field of residual vorticity whose magnitude is used to define vortex regions. The present method allows to locate automatically the core of each vortex, quantify its strength and determine the vortex bounding surface. The output may be used to visualize the turbine vortical structures for the purpose of interpreting the complex three-dimensional viscous flow field, as well as to highlight any case-to-case variations by quantifying the vortex strength and location. The vortex identification method is applied to a high-pressure turbine with three optimized blade tip geometries. The 3D flow-field is obtained by CFD computations performed with Numeca FINE/Open. The computational model uses steady-state RANS equations closed by the Spalart-Allmaras turbulence model. Although developed for turbomachinery applications, the vortex identification method proposed in this work is of general applicability to any three-dimensional flow-field.
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Shobayo, Olalekan O., and D. Keith Walters. "Evaluation of a Statistically Targeted Forcing Method for Synthetic Turbulence Generation in Large-Eddy Simulations and Hybrid RANS-LES Simulations." In ASME 2020 Fluids Engineering Division Summer Meeting collocated with the ASME 2020 Heat Transfer Summer Conference and the ASME 2020 18th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/fedsm2020-20376.

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Abstract Computational fluid dynamics (CFD) results are presented for synthetic turbulence generation by a proposed statistically targeted forcing (STF) method. The new method seeks to introduce a fluctuating velocity field with a distribution of first and second moments that match a user-specified target mean velocity and Reynolds stress tensor, by incorporating deterministic time-dependent forcing terms into the momentum equation for the resolved flow. The STF method is formulated to extend the applicability of previously documented methods and provide flexibility in regions where synthetic turbulence needs to be generated or damped, for use in engineering level large-eddy and hybrid large-eddy/Reynolds-averaged Navier-Stokes CFD simulations. The objective of this study is to evaluate the performance of the proposed STF method in LES simulations of isotropic and anisotropic homogeneous turbulent flow test cases. Results are interrogated and compared to target statistical velocity and turbulent stress distributions and evaluated in terms of energy spectra. Analysis of the influence of STF model parameters, mesh resolution, and LES subgrid stress model on the results is investigated. Results show that the new method can successfully reproduce desired statistical distributions in a homogeneous turbulent flow.
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Lengani, D., D. Simoni, M. Ubaldi, P. Zunino, F. Bertini, and V. Michelassi. "Accurate Estimation of Profile Losses and Analysis of Loss Generation Mechanisms in a Turbine Cascade." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-64244.

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The paper analyzes losses and the loss generation mechanisms in a low-pressure turbine cascade by Proper-Orthogonal-Decomposition (POD) applied to measurements. Total pressure probes and time resolved particle image velocimetry (TR-PIV) are used to determine the flow field and performance of the blade with steady and unsteady inflow conditions varying the flow incidence. The total pressure loss co-efficient is computed by traversing two Kiel probes upstream and downstream of the cascade simultaneously. This procedure allows a very accurate estimation of the total pressure loss coefficient also in the potential flow region affected by incoming wake migration. The TR-PIV investigation concentrates on the aft portion of the suction side boundary layer downstream of peak suction. In this adverse pressure gradient region the interaction between the wake and the boundary layer is the strongest, and it leads to the largest deviation from a steady loss mechanism. POD applied to this portion of the domain provides a statistical representation of the flow oscillations by splitting the effects induced by the different dynamics. The paper also describes how POD can dissect the loss generation mechanisms by separating the contributions to the Reynolds stress tensor from the different modes. The steady condition loss generation, driven by boundary layer streaks and separation is augmented in presence of incoming wakes by the wake-boundary layer interaction and by the wake dilation mechanism. Wake migration losses have been found to be almost insensitive to incidence variation between nominal and negative (up to −9deg), while at positive incidence the losses have a steep increase due to the alteration of the wake path induced by the different loading distribution.
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Dellacasagrande, M., D. Lengani, D. Simoni, M. Ubaldi, and P. Zunino. "Experimental Investigation on the Loss Production Mechanisms in Transitional Boundary Layers." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-15148.

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Abstract The present paper discusses the results of a large experimental data set describing transitional boundary layers. Time resolved Particle Image Velocimetry (PIV) measurements have been adopted to survey the boundary layer developing over a flat plate under prescribed adverse pressure gradients typical of turbomachinery components. The tests have been performed while varying the pressure gradient, the Reynolds number and the inlet free-stream turbulence intensity (FSTI). Two exemplary cases, referring to bypass and separated flow transition, are discussed by means of principal axis analysis and proper orthogonal decomposition (POD). The POD is used to provide statistical representation of the flow structures and to compute the turbulence production (i.e., the mean flow energy dissipation) due to the dynamical features observed for the different transition types. Reduced order model representations of the flow field are provided and their contribution to the total turbulence kinetic energy production is isolated. This analysis is closed by the inspection of the eigenvectors of the strain rate and Reynolds stress tensors. For the separated flow case, it is shown that the eigenvectors of strain rate and shear tensor are almost perfectly aligned downstream of the maximum displacement of the bubble. The reduced order model reconstruction of the Kelvin-Helmholtz shed vortices provides the largest part of the overall TKE production. For the high FSTI induced transition, the eigenvectors of the shear and stress tensors do not have the same direction. The loss generation is related to the local maximum Reynolds normal stress in the streamwise direction, induced by the boundary layer streaks and their breakdown.
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Geist, Silvio, Janneck Harbeck, and Franz Joos. "A 3D-LDA Study of the Relation Between Coincident and Time Stepped Non-Coincident Stress Measurements in a Linear Compressor Cascade." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-76573.

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Especially in the turbulence research, it is necessary to record three velocity components concurrently. As a result, all six components of the Reynolds stress tensor and higher-order velocity correlations can be determined. This article assesses the three-dimensional flow field of a linear transonic compressor cascade. The velocity field within the blade passage is measured using a 3D-LDA system. This requires a coincident measurement of the velocity. However, this leads to a significant reduction in the data rate. To circumvent this problem there is the general approach of a record interval window to the subsequent generation of coincident data. In comparison to previous publications, a transonic flow is considered here. For a coincident measurement it is essential that all velocities are perpendicular to each other. Because of limited arrangement possibility of the probes the system measures three non orthogonal velocity components. Therefore, a coordinate transformation is necessary. Due to uncertainties in the exact laser alignments, the transformation matrix for this arrangement is determined experimentally. This paper deals with these two problems, for a case similar to gas turbine conditions. The influence of the time interval on the measured data is compared with coincident data. Within the cascade different measuring planes are considered and a time step study is carried out.
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Nomura, Kazuya, Akihiko Ikeda, Yoshimitsu Kohama, Yasuhiro H. Matsuda, Shojiro Takeyama, Naoki Amaya, Toshio Ono, and Yuko Hosokoshi. "Spin-lattice separation of the spin-ladder compound BIP-TENO by microsecond megagauss field." In 2018 16th International Conference on Megagauss Magnetic Field Generation and Related Topics (MEGAGAUSS). IEEE, 2018. http://dx.doi.org/10.1109/megagauss.2018.8722650.

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Ferna´ndez Oro, J., K. Argu¨elles Di´az, C. Santolaria Morros, and R. Ballesteros Tajadura. "Unsteady Flow Analysis of the Stator-Rotor Interaction in an Axial Flow Fan." In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45394.

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In the usual operation of turbomachinery, some unsteady flow phenomena appear due to the non uniformity of the flow inside the rotor, when observed in the fixed reference frame. These phenomena are often related to the unsteady character of the pressure and velocity fields, which produce oscillating forces on the blades, superimposed to the steady force. These oscillating forces are the main mechanism of noise generation, which appear even at a constant rotational speed and at flow rates where the performance curves are stable. In axial turbomachines, the interaction is due to relative motion between the static and rotating blade rows. Considering the case of a fixed blade row (stator) placed upstream of the rotor, the non uniform flow leaving those blades (usually referred as IGV blades) is observed as an unsteady flow by the rotor blades. The effect of this interaction is the generation of unsteady forces on the rotor blades, which generate vibrations (risk of fatigue failure) and noise, and non-uniformity and unsteadiness of the pressure field, that propagates as an acoustic wave. The first part of this work is a brief description of a URANS numerical modeling of the unsteady flow characteristics of a one-stage subsonic axial flow fan with a reaction degree greater than 1. The focus is placed on the statorrotor interaction performance. Both 2D and 3D models of the fan, with 13 IGV’s and 9 rotor blades, were developed and an unsteady simulation was achieved to carry out the main characteristics of the flow inside the turbomachine. Once the actuating forces are determined, the influence of the radial position, the operating conditions and the distance of the fixed and the rotating blade rows is also analyzed. The final part of the paper is focused over the identification, through the definition of deterministic stresses — related to the characteristic blade-passage frequency of every row — that provoke the interaction between fixed and rotating blade rows and its evolution through time. The object is to obtain, in a stress tensor form, the contribution of the velocity field, that is changing because of the sucessive relative positions between blade rows, to the pressure distribution over the blade surfaces in the interior of the stage. Finally, a map of deterministic stresses and even, deterministic kinetic energy, can be obtained to show the influence of the blade rows in the interaction, unsteady phenomena.
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Wallace, Wayne, and Peter J. Carrato. "Squirter™ DTI’s Make SCR/HRSG Bolting Easy." In 2002 International Joint Power Generation Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/ijpgc2002-26018.

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Field installation and inspection of structural bolts in SCR’s and HRSG’s consume thousands of man-hours. Bolts are installed by various qualities of labor: ironworkers, boilermakers, pipefitters, millwrights, laborers, or non-union workers, especially in offshore locations. Project schedules require rapid assembly of steelwork so that the mechanical systems can be located and made operational in the least possible time. Tightening specifications for bolts used in these applications change frequently, and field personnel often have difficulty keeping abreast of the changes. Direct Tension Indicating (DTI) washers have made bolt tightening in these applications more or less foolproof for twenty or more years, but their installation and inspection has been labor-intensive. With the development of the DTI ‘Squirter Washer’, bolts can be tightened and inspected in about one-half the time previously devoted to this operation. Duke/Fluor Daniel, Bechtel, Babcock & Wilcox, The Industrial Company, and other contractors are now using Squirter DTI’s and sharing the savings with their client power project owners.
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