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Analysis of Modeling the Influence of Electromagnetic Fields Radiated by Industrial Static Converters and Impacts on Operators Using Maxwell’s Equations
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作者 Anthony Bassesuka Sandoka Nzao Tuka Biaba Samuel Garcia +2 位作者 Obed Bitala Arsène Kasereka Kibwana Emmanuel Ndaye Kibuayi 《Open Journal of Applied Sciences》 2024年第8期2320-2350,共31页
The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of... The study of Electromagnetic Compatibility is essential to ensure the harmonious operation of electronic equipment in a shared environment. The basic principles of Electromagnetic Compatibility focus on the ability of devices to withstand electromagnetic disturbances and not produce disturbances that could affect other systems. Imperceptible in most work situations, electromagnetic fields can, beyond certain thresholds, have effects on human health. The objective of the present article is focused on the modeling analysis of the influence of geometric parameters of industrial static converters radiated electromagnetic fields using Maxwell’s equations. To do this we used the analytical formalism for calculating the electromagnetic field emitted by a filiform conductor, to model the electromagnetic radiation of this device in the spatio-temporal domain. The interactions of electromagnetic waves with human bodies are complex and depend on several factors linked to the characteristics of the incident wave. To model these interactions, we implemented the physical laws of electromagnetic wave propagation based on Maxwell’s and bio-heat equations to obtain consistent results. These obtained models allowed us to evaluate the spatial profile of induced current and temperature of biological tissue during exposure to electromagnetic waves generated by this system. The simulation 2D results obtained from computer tools show that the temperature variation and current induced by the electromagnetic field can have a very significant influence on the life of biological tissue. The paper provides a comprehensive analysis using advanced mathematical models to evaluate the influence of electromagnetic fields. The findings have direct implications for workplace safety, potentially influencing standards and regulations concerning electromagnetic exposure in industrial settings. 展开更多
关键词 MODELING Electromagnetic field Power Converters Geometric Parameters Biological Tissue Maxwell Equation Bio-Heat Equation Thermal Model
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Time-periodic solutions of the Einstein's field equations Ⅰ:general framework 被引量:5
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作者 KONG DeXing1 & LIU KeFeng2 1Department of Mathematics,Zhejiang University,Hangzhou 310027,China 2Department of Mathematics,University of California at Los Angeles,CA 90095,USA 《Science China Mathematics》 SCIE 2010年第5期176-193,共18页
In this paper,we develop a new algorithm to find the exact solutions of the Einstein's field equations.Time-periodic solutions are constructed by using the new algorithm.The singularities of the time-periodic solu... In this paper,we develop a new algorithm to find the exact solutions of the Einstein's field equations.Time-periodic solutions are constructed by using the new algorithm.The singularities of the time-periodic solutions are investigated and some new physical phenomena,such as degenerate event horizon and time-periodic event horizon,are found.The applications of these solutions in modern cosmology and general relativity are expected. 展开更多
关键词 Einstein’s field equations time-periodic solution RIEMANN CURVATURE TENSOR SINGULARITY event HORIZON
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Time-periodic solutions of the Einstein's field equations II:geometric singularities 被引量:3
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作者 KONG DeXing1,LIU KeFeng2,& SHEN Ming3 1Department of Mathematics,Zhejiang University,Hangzhou 310027,China 2Department of Mathematics,University of California at Los Angeles,CA 90095,USA 3Center of Mathematical Sciences,Zhejiang University,Hangzhou 310027,China 《Science China Mathematics》 SCIE 2010年第6期1507-1520,共14页
In this paper,we construct several kinds of new time-periodic solutions of the vacuum Einstein's field equations whose Riemann curvature tensors vanish,keep finite or take the infinity at some points in these spac... In this paper,we construct several kinds of new time-periodic solutions of the vacuum Einstein's field equations whose Riemann curvature tensors vanish,keep finite or take the infinity at some points in these space-times,respectively.The singularities of these new time-periodic solutions are investigated and some new physical phenomena are discovered. 展开更多
关键词 Einstein’s field equations time-periodic solution RIEMANN curvature TENSOR SINGULARITY event HORIZON
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How Classical, Quantum-Mechanical, and Relativistic Wave and Field Equations Are Uniformly Generated by Velocity-Field Divergence Equations
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作者 Frank Blume 《Journal of Applied Mathematics and Physics》 2023年第9期2739-2764,共26页
We expand previously established results concerning the uniform representability of classical and relativistic gravitational field equations by means of velocity-field divergence equations by demonstrating that conser... We expand previously established results concerning the uniform representability of classical and relativistic gravitational field equations by means of velocity-field divergence equations by demonstrating that conservation equations for (probability) density functions give rise to velocity-field divergence equations the solutions of which generate—by way of superposition—the totality of solutions of various well-known classical and quantum-mechanical wave equations. 展开更多
关键词 Uniform Representability Gravitational field equations Velocity-field Divergence equations Conservation equations Wave equations
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Time-periodic solutions of the Einstein's field equations Ⅲ:physical singularities 被引量:2
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作者 KONG DeXing LIU KeFeng SHEN Ming 《Science China Mathematics》 SCIE 2011年第1期23-33,共11页
In this paper we construct a new time-periodic solution of the vacuum Einstein's field equations, this solution possesses physical singularities, i.e., the norm of the solution's Riemann curvature tensor takes... In this paper we construct a new time-periodic solution of the vacuum Einstein's field equations, this solution possesses physical singularities, i.e., the norm of the solution's Riemann curvature tensor takes the infinity at some points. We show that this solution is intrinsically time-periodic and describes a time-periodic universe with the "time-periodic physical singularity". By calculating the Weyl scalars of this solution, we investigate new physical phenomena and analyze new singularities for this universal model. 展开更多
关键词 Einstein's field equations time-periodic solution geometric singularity physical singularity Weyl scalar
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The Maxwell-Heaviside Equations Explained by the Theory of Informatons
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作者 Antoine Acke 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1003-1016,共14页
In the articles “Newtons Law of Universal Gravitation Explained by the Theory of Informatons” and “The Gravitational Interaction between Moving Mass Particles Explained by the Theory of Informatons” the gravitatio... In the articles “Newtons Law of Universal Gravitation Explained by the Theory of Informatons” and “The Gravitational Interaction between Moving Mass Particles Explained by the Theory of Informatons” the gravitational interaction has been explained by the hypothesis that information carried by informatons is the substance of gravitational fields, i.e. the medium that the interaction in question makes possible. From the idea that “information carried by informatons” is its substance, it has been deduced that—on the macroscopic level—a gravitational field manifests itself as a dual entity, always having a field- and an induction component (Egand Bg) simultaneously created by their common sources. In this article we will mathematically deduce the Maxwell-Heaviside equations from the kinematics of the informatons. These relations describe on the macroscopic level how a gravitational field (Eg, Bg) is generated by whether or not moving masses and how spatial and temporal changes of Egand Bgare related. We show that there is no causal link between Egand Bg. 展开更多
关键词 GRAVITY Gravitational field Maxwell equations Informatons
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An Explanation of the Temperature-Dependent Upper Critical Field Data of H3S on the Basis of the Thermodynamics of a Superconductor in a Magnetic Field
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作者 Gulshan Prakash Malik 《World Journal of Condensed Matter Physics》 CAS 2024年第3期45-50,共6页
Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtai... Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtained by Talantsev (2019) in an approach based on an ingenious mix of the Ginzberg-Landau (GL), the Werthamer, Helfand and Hohenberg (WHH), and the Gor’kov, etc., theories which have individually been employed for the same purpose for a long time. Up to the lowest temperature (TL) in each of these data-sets, similarly accurate fits have also been obtained by Malik and Varma (2023) in a radically different approach based on the Bethe-Salpeter equation (BSE) supplemented by the Matsubara and the Landau quantization prescriptions. For T TL, however, while the (GL, WHH, etc.)-based approach leads to Hc2(0) ≈ 100 T, the BSE-based approach leads to about twice this value even at 1 K. In this paper, a fit to one of the said data-sets is obtained for the first time via a thermodynamic approach which, up to TL, is as good as those obtained via the earlier approaches. While this is interesting per se, another significant result of this paper is that for T TL it corroborates the result of the BSE-based approach. 展开更多
关键词 H3S Upper Critical field (Hc2) Variation of Hc2 with Temperature Clausius-Clapeyron equation in a magnetic field Behavior of Hc2 for Temperatures Close to 0 K
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Time-Machine Solutions of Einstein's Equations with Electromagnetic Field
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作者 沈明 孙庆有 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期69-71,共3页
In this paper we investigate the time-machine problem in the electromagnetic field. Based on a metric which is a more general form of Ori's, we solve the Einstein's equations with the energy-momentum tensors for ele... In this paper we investigate the time-machine problem in the electromagnetic field. Based on a metric which is a more general form of Ori's, we solve the Einstein's equations with the energy-momentum tensors for electromagnetic field, and construct the time-machine solutions, which solve the time machine problem in electromagnetic field. 展开更多
关键词 time-machine solutions closed timelike curves Einstein's equations energy-momentum tensor electromagnetic field energy conditions
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Diffusion Equations of the Electric Charges and Magnetic Flux
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作者 Salama Abdelhady Mohamed S. Abdelhady 《Journal of Electromagnetic Analysis and Applications》 2024年第5期69-83,共15页
Innovative definitions of the electric and magnetic diffusivities through conducting mediums and innovative diffusion equations of the electric charges and magnetic flux are verified in this article. Such innovations ... Innovative definitions of the electric and magnetic diffusivities through conducting mediums and innovative diffusion equations of the electric charges and magnetic flux are verified in this article. Such innovations depend on the analogy of the governing laws of diffusion of the thermal, electrical, and magnetic energies and newly defined natures of the electric charges and magnetic flux as energy, or as electromagnetic waves, that have electric and magnetic potentials. The introduced diffusion equations of the electric charges and magnetic flux involve Laplacian operator and the introduced diffusivities. Both equations are applied to determine the electric and magnetic fields in conductors as the heat diffusion equation which is applied to determine the thermal field in steady and unsteady heat diffusion conditions. The use of electric networks for experimental modeling of thermal networks represents sufficient proof of similarity of the diffusion equations of both fields. By analysis of the diffusion phenomena of the three considered modes of energy transfer;the rates of flow of these energies are found to be directly proportional to the gradient of their volumetric concentration, or density, and the proportionality constants in such relations are the diffusivity of each energy. Such analysis leads also to find proportionality relations between the potentials of such energies and their volumetric concentrations. Validity of the introduced diffusion equations is verified by correspondence their solutions to the measurement results of the electric and magnetic fields in microwave ovens. 展开更多
关键词 Diffusion Coefficient Diffusion Equation Electric Charge Magnetic Flux Electromagnetic Waves Electric field Magnetic field
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A NEW CLASS OF SOLUTIONS OF VACUUM EINSTEIN'S FIELD EQUATIONS WITH COSMOLOGICAL CONSTANT
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作者 Ming Shen Qiaorong Zhuang 《Annals of Applied Mathematics》 2016年第1期36-41,共6页
In this paper, a new class of solutions of the vacuum Einstein's field equa- tions with cosmological constant is obtained. This class of solutions possesses the naked physical singularity. The norm of the Riemann cur... In this paper, a new class of solutions of the vacuum Einstein's field equa- tions with cosmological constant is obtained. This class of solutions possesses the naked physical singularity. The norm of the Riemann curvature tensor of this class of solutions takes infinity at some points and the solutions do not have any event horizon around the singularity. 展开更多
关键词 vacuum Einstein's field equations cosmological constant ex-act solutions naked physical singularity
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Dynamic of Scalar Bosons in Aharonov-Bohm Magnetic Field
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作者 Frédéric D. Y. Zongo 《Journal of Applied Mathematics and Physics》 2024年第1期268-276,共9页
We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the follo... We study the dynamic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the differential equation that governs this dynamic. Secondly, we use variational techniques to show that the following Schrödinger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground-state solution. 展开更多
关键词 Scalar Boson Aharonov-Bohm Magnetic field Schrödinger-Newton Equation Ground-State Solution
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Generally Unitary Solution to a System of Matrix Equations over the Quaternion Field
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作者 周立泰 汪远征 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期91-93,共3页
Generally unitary solution to the system of martix equations over the quaternion field [X mA ns =B ns ,X nn C nt =D nt ] is considered. A necessary and sufficient condition for the existence o... Generally unitary solution to the system of martix equations over the quaternion field [X mA ns =B ns ,X nn C nt =D nt ] is considered. A necessary and sufficient condition for the existence of and the expression for the generally unitary solution of the system are derived. 展开更多
关键词 generally unitary matrix system of matrix equations the quaternion field
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Minor Self-conjugate and Skewpositive Semidefinite Solutions to a System of Matrix Equations over Skew Fields
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作者 姜学波 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期86-90,共5页
Minor self conjugate (msc) and skewpositive semidefinite (ssd) solutions to the system of matrix equations over skew fields [A mn X nn =A mn ,B sn X nn =O sn ] are considered. Necessary and su... Minor self conjugate (msc) and skewpositive semidefinite (ssd) solutions to the system of matrix equations over skew fields [A mn X nn =A mn ,B sn X nn =O sn ] are considered. Necessary and sufficient conditions for the existence of and the expressions for the msc solutions and the ssd solutions are obtained for the system. 展开更多
关键词 minor self conjugate matrix skewpositive semidefinite matrix system of matrix equations skew field the real quatrnion field
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Average vector field methods for the coupled Schrdinger KdV equations 被引量:3
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作者 张弘 宋松和 +1 位作者 陈绪栋 周炜恩 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期242-250,共9页
The energy preserving average vector field (AVF) method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction di... The energy preserving average vector field (AVF) method is applied to the coupled Schr6dinger-KdV equations. Two energy preserving schemes are constructed by using Fourier pseudospectral method in space direction discretization. In order to accelerate our simulation, the split-step technique is used. The numerical experiments show that the non-splitting scheme and splitting scheme are both effective, and have excellent long time numerical behavior. The comparisons show that the splitting scheme is faster than the non-splitting scheme, but it is not as good as the non-splitting scheme in preserving the invariants. 展开更多
关键词 coupled Schrodinger-KdV equations average vector field method splitting method Fourier pseu-dospectral method
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Multi-quadric Equations Interpolation and Its Applications to the Establishment of Crustal Movement Speed Field 被引量:4
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作者 YAO Yibin LIU Jingnan SHI Chuang TAO Benzao 《Geo-Spatial Information Science》 2002年第2期1-5,共5页
In this paper,multi_quadric equations interpolation is used to establish a widely covered and valuable speed field model,with which the crustal movement image is obtained.
关键词 multi_quadric equations interpolation speed field model crustal movement pattern
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Plane Symmetric Solutions to the Nonlinear Spinor Field Equations in General Relativity Theory 被引量:5
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作者 A. Adomou Jonas Edou Siaka Massou 《Journal of Modern Physics》 2019年第10期1222-1234,共13页
We have obtained exact static plane-symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of invariant , taking into account their own gravitational field. It is shown th... We have obtained exact static plane-symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of invariant , taking into account their own gravitational field. It is shown that the initial set of the Einstein and spinor field equations with a power-law nonlinearity have regular solutions with a localized energy density of the spinor field only if m=0 (m is the mass parameter in the spinor field equations). Equations with power and polynomial nonlinearities are studied in detail. In this case, a soliton-like configuration has negative energy. We have also obtained exact static plane-symmetric solutions to the above spinor field equations in flat space-time. It is proved that in this case soliton-like solutions are absent. 展开更多
关键词 LAGRANGIAN Static Plane-Symmetric Metric field equations ENERGY-MOMENTUM Tensor Charge Density Current Vector SOLITON-LIKE Solution
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Nonlinear Spinor Field Equations in Gravitational Theory: Spherical Symmetric Soliton-Like Solutions 被引量:2
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作者 V. Adanhounme A. Adomou +1 位作者 F. P. Codo M. N. Hounkonnou 《Journal of Modern Physics》 2012年第9期935-942,共8页
This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitra... This paper deals with an extension of a previous work [Gravitation & Cosmology, Vol. 4, 1998, pp 107-113] to exact spherical symmetric solutions to the spinor field equations with nonlinear terms which are arbitrary functions of S=ψψ, taking into account their own gravitational field. Equations with power and polynomial nonlinearities are studied in detail. It is shown that the initial set of the Einstein and spinor field equations with a power nonlinearity has regular solutions with spinor field localized energy and charge densities. The total energy and charge are finite. Besides, exact solutions, including soliton-like solutions, to the spinor field equations are also obtained in flat space-time. 展开更多
关键词 Lagrangian Static SPHERICAL SYMMETRIC Metric field equations EINSTEIN equations Dirac Equation ENERGY-MOMENTUM Tensor Charge Density Current Vector SOLITON-LIKE Solution
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The General and Centro(Kewsy) Symmetric Solutions to a System of Matrix Equations over an Arbitrary Skew Field 被引量:3
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作者 QIN Jian-guo SONG Guang-ai 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期66-70,共5页
Necessary and sufficient conditions are given for the existence of the general solution, the centrosymmetric solution, and the centroskewsymmetric solution to a system of linear matrix equations over an arbitrary skew... Necessary and sufficient conditions are given for the existence of the general solution, the centrosymmetric solution, and the centroskewsymmetric solution to a system of linear matrix equations over an arbitrary skew field. The representations of such the solutions of the system are also derived. 展开更多
关键词 system of matrix equations inner inverse of a matrix reflexive inverse of a matrix centro (skew) symmetric matrix skew field
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On the Field Equations of General Relativity 被引量:1
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作者 Vu B. Ho 《Journal of Applied Mathematics and Physics》 2022年第1期49-55,共7页
In this work, we examine the geometric character of the field equations of general relativity and propose to formulate relativistic field equations in terms of the Riemann curvature tensor. The resulted relativistic f... In this work, we examine the geometric character of the field equations of general relativity and propose to formulate relativistic field equations in terms of the Riemann curvature tensor. The resulted relativistic field equations are also integrated into the general framework that we have presented in our previous works that all known classical fields can be expressed in the same dynamical form. We also discuss a possibility to reformulate the field equations of general relativity so that the Ricci curvature tensor and the energy-momentum tensor can appear symmetrically in the field equations without violating the conservation law stated by the covariant derivative. 展开更多
关键词 General Relativity Classical field equations Riemann Curvature Tensor
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CONSTITUTIVE RELATION OF UNSATURATED SOIL BY USE OF THE MIXTURE THEORY (Ⅱ)—LINEAR CONSTITUTIVE EQUATIONS AND FIELD EQUATIONS
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作者 黄义 张引科 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期138-152,共15页
The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the for... The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the forms similar to Biot's equations for saturated porous media. The Darcy's laws of unsaturated soil were proved. It is shown that Biot's equations of saturated porous media are the simplification of the theory. All these illustrate that constructing constitutive relation of unsaturated soil on the base of mixture theory is rational. 展开更多
关键词 mixture theory unsaturated soil linear constitutive equation linear field equation Darcy's law Biot's equations
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