Transverse Vector Research Articles

Numerical analysis of two-dimensional motion of a freely falling circular cylinder in an infinite fluid

The two-dimensional motion of a circular cylinder freely falling or rising in an infinite fluid is investigated numerically for the range of Reynolds number Re, < 188 (Galileo number G < 163), where the wake behind the cylinder remains two-dimensional, using a combined formulation of the governing equations for the fluid and the dynamic equations for the cylinder. The effect of vortex shedding on the motion of the freely falling or rising cylinder is clearly shown. As the streamwise velocity of the cylinder increases due to gravity, the periodic vortex shedding induces a periodic motion of the cylinder, which is manifested by the generation of the angular velocity vector of the cylinder parallel to the cross-product of the gravitational acceleration vector and the transverse velocity vector of the cylinder. Correlations of the Strouhal–Reynolds-number and Strouhal–Galileo-number relationship are deduced from the results. The Strouhal number is found to be smaller than that for the corresponding fixed circular cylinder when the two Reynolds numbers based on the streamwise terminal velocity of the freely falling or rising circular cylinder and the free-stream velocity of the fixed one are the same. From numerical experiments, it is shown that the transverse motion of the cylinder plays a crucial role in reducing the Strouhal number. The effect of the transverse motion is similar to that of suction flow on the low-pressure side, where a vortex is generated and then separates, so that the pressure on this side recovers with the vortex separation retarded. The effects of the transverse motion on the lift, drag and moment coefficients are also discussed. Finally, the effect of the solid/fluid density ratio on Strouhal–Reynolds-number relationship is investigated and a plausible correlation is proposed.

M31 Transverse Velocity and Local Group Mass from Satellite Kinematics

We present several different statistical methods to determine the transverse velocity vector of M31. The underlying assumptions are that the M31 satellites on average follow the motion of M31 through space, and that the galaxies in the outer parts of the Local Group on average follow the motion of the Local Group barycenter through space. We apply the methods to the line-of-sight velocities of 17 M31 satellites, to the proper motions of the 2 satellites M33 and IC 10, and to the line-of-sight velocities of 5 galaxies near the Local Group turn around radius, respectively. This yields 4 independent but mutually consistent determinations of the heliocentric M31 transverse velocities in the West and North directions, with weighted averages = -78+/-41 km/s and = -38+/-34 km/s. The Galactocentric tangential velocity of M31 is 42 km/s, with 1-sigma confidence interval V_tan <= 56 km/s. The implied M31-Milky Way orbit is bound if the total Local Group mass M exceeds 1.72^{+0.26}_{-0.25}x10^{12} solar masses. If indeed bound, then the timing argument combined with the known age of the Universe implies that M = 5.58^{+0.85}_{-0.72}x10^{12} solar masses. This is on the high end of the allowed mass range suggested by cosmologically motivated models for the individual structure and dynamics of M31 and the Milky Way, respectively. It is therefore possible that the timing mass is an overestimate of the true mass, especially if one takes into account recent results from the Millennium Simulation that show that there is also a theoretical uncertainty of 41 percent (Gaussian dispersion) in timing mass estimates. The M31 transverse velocity implies that M33 is in a tightly bound orbit around M31. This may have led to some tidal deformation of M33. It will be worthwhile to search for observational evidence of this.

Numerical investigation of scaling regimes in a model of an anisotropically advected vector field

Influence of strong uniaxial small-scale anisotropy on the stability of inertial-range scaling regimes in a model of a passive transverse vector field advected by an incompressible turbulent flow is investigated by means of the field theoretic renormalization group. Turbulent fluctuations of the velocity field are taken to have the Gaussian statistics with zero mean and defined noise with finite correlations in time. It is shown that stability of the inertial-range scaling regimes in the three-dimensional case is not destroyed by anisotropy, but the corresponding stability of the two-dimensional system can be corrupted by the presence of anisotropy. A borderline dimension dc below which the stability of the scaling regime is not present is calculated as a function of anisotropy parameters.

Highly Birefringent Photonic Crystal Fibers With Ultralow Chromatic Dispersion and Low Confinement Losses

Highly birefringent photonic crystal fibers (PCFs) with low confinement loss with ultralow and ultraflattened chromatic dispersions at wide wavelength band are presented. The transverse electric field vector distributions of two linearly polarized fundamental modes, their effective indices, modal birefringence, confinement losses and chromatic dispersion of the proposed PCFs are reported by using full-vector finite-element method (FEM). Significant improvements of PCFs in terms of the birefringence, chromatic dispersion and confinement losses are demonstrated by careful investigation of all air holes in each ring, air holes diameters and hole-to-hole spacing. In addition to this, the polarization beat length results of the proposed PCFs are also reported and discussed thoroughly.

Reduced Complexity Solution for Weight Extraction in QRD-LSL Algorithms

QR-decomposition-based least-squares lattice (QRD-LSL) algorithms do not provide the transversal weight vector in explicit form. These weights can be computed from the variables of the QRD-LSL algorithm using the Levinson-Durbin (LD) recursion. If the prediction coefficients do not vary over time, a reduced complexity but approximate solution can be obtained. Nonetheless, this approximate solution requires algorithm convergence and infinite memory support (forgetting factor equal to one). To obtain the exact weights at any time instant and for any choice of the forgetting factor, the computational complexity of the true LD recursion increases by an order of magnitude. In this letter, we show that an exact solution can be obtained with a reduced computational complexity and without any added restriction. Simulation results show that the solutions obtained using the proposed method and the exact LD recursion are the same up to the precision used, whereas the weights from the approximate method always deviate from the true solution.

쌍축 컨테이너선의 선미선형 변화에 따른 유동 특성에 대한 수치해석

Numerical analysis for flow characteristics of a twin skeg container ship was carried out according to skeg vertical angles(<TEX>$0^{\circ}$</TEX>, <TEX>$10^{\circ}$</TEX>, <TEX>$20^{\circ}$</TEX>) and skeg distances(16m, 20m, 24m) by using a commercial CFD code, FLUENT. Computed: pressure distributions, wake distributions and resistance coefficients have been compared with experimental and WAVIS results carried out by MOERI. Flow characteristics from numerical analysis such as nominal wake fractions, wake distribution and directions of the transverse vectors give good agreement with WAVIS results, even though there are quantitative discrepancy comparing with experimental measurements at the propeller plane. It is found that the better resistance performance can be obtained with the increase of the skeg vertical angle and the decrease of the skeg distance, which are mainly caused by viscous pressure resistance due to the skeg form and pressure recovery around the skeg. In addition, a vertical angle of the skeg gives more effect to the resistance coefficient comparing with the skeg distance. On the basis of results of the present study, it shows that numerical analysis using the commercial code, FLUENT, is useful and efficient tool for the evaluation of the complex stern hull form with twin-skegs.

Geometric and transformational properties of Lipschitz domains, Semmes-Kenig-Toro domains, and other classes of finite perimeter domains

In the first part of this article we give intrinsic characterizations of the classes of Lipschitz and C1 domains. Under some mild, necessary, background hypotheses (of topological and geometric measure theoretic nature), we show that a domain is Lipschitz if and only if it has a continuous transversal vector field. We also show that if the geometric measure theoretic unit normal of the domain is continuous, then the domain in question is of class C1. In the second part of the article, we study the invariance of various classes of domains of locally finite perimeter under bi-Lipschitz and C1 diffeomorphisms of the Euclidean space. In particular, we prove that the class of bounded regular SKT domains (previously called chord-arc domains with vanishing constant, in the literature) is stable under C1 diffeomorphisms. A number of other applications are also presented.

Swiss roll lattices: numerical and asymptotic modeling

The design of metamaterials for microwave devices with new properties is an active field of research. Various kinds of structures such as the ‘Swiss roll’ are proposed as candidates with innovative properties. In order to model such structures, we consider the out-of-plane propagation of electromagnetic waves in a lattice with arbitrary dielectric or perfectly conducting inclusions. The problem is reduced to finding Bloch modes characterized by a transverse Bloch propagation vector, a longitudinal propagation constant, and a pulsation. The dispersion curves obtained give the relevant information on the physical properties of the equivalent material. Eventually, an asymptotic approach is given which allows us not only to foresee the first dispersion curves but also to determine precisely enough the main characteristics of the map of the corresponding modes.

CFD를 이용한 쌍축 컨테이너선 주위의 유동계산

In this study. a numerical analysis has been performed for the turbulent flow around a 15,000TEU twin-skeg container ship using a commercial CFD code. FLUENT. The computed results have been compared with the model test data from MOERI. We investigated viscous resistance coefficient. wake distribution and characteristics of the shear flow according to the grid numbers. Although the free surface is approximated by the plane of symmetry in this work. the calculated axial velocity and transverse vector show a good agreement with the MOERI experimental data except for the region of 0.9 level of axial velocity at the propeller plane. The numerical analysis show that commercial CFD code is useful tool for the evaluation of complex hull form with twin-skegs.

Holographic [formula omitted] Multiplets

In this communication we report on the results of the study of the holographic dual for the anomaly and gravity N = 1 multiplets in the baryonic branch generalization of the Klebanov-Strassler background. We present the equation for the transverse vector glueball in KS case. The spectrum of low lying excitations coincides with the spectrum of the traceless graviton. The anomalous longitudinal part of the the current is degenerate with the scalar glueball, that is a perturbation of the trace of the metric. The latter glueballs are lighter than the gravity multiplet everywhere on baryonic branch.

Linear Gauge and the Linearization Problem for Webs

Regarding the theory of foliation, some aspects of the theory of Riemannian foliations have been brought in completion by the Molino theory. Such a structure is defined by some finite dimensional Lie subalgebra of the Lie algebra of transverse vector fields. The problem I am interested in is more modeste. It is to get sufficient conditions for a smooth manifold admitting foliations with transverse (pseudo) Riemannian metrics. The investigation is inspired by both methods of information geometry and the Hessian geometry.

ON SOME INFINITESIMAL AUTOMORPHISMS OF RIEMANNIAN FOLIATION

In Riemannian foliation, a transverse affine vector field preserves the curvature and its covariant derivatives. In this paper we solve the converse problem. Actually, we show that an infinitesimal automorphism of a Riemannian foliation which preserves the curvature and its covariant derivatives induces a transverse almost homothetic vector field. If in addition the manifold is closed and the foliation is irreducible harmonic, then a such infinitesimal automorphism induces a transverse killing vector field.

Propagation properties of vector Mathieu–Gauss beams

The vector Helmholtz–Gauss (vHzG) beam is known as a general family of localized vector beam solutions of the Maxwell equations in the paraxial limit and the vector Mathieu–Gauss beam constitutes its version in elliptic cylindrical coordinates system. In this work, starting from the expansion of the scalar Mathieu–Gauss beam in term of Bessel–Gauss beams, we give a general expression of vector Mathieu–Gauss beams in cylindrical coordinates. Within the frame work of the Collins diffraction integral formula we derive the analytical expressions of transverse vector Mathieu–Gauss beams through an axisymmetric ABCD optical system. Some numerical calculations are performed to illustrate the propagation of the vector Mathieu–Gauss beam in free space and through a simple lens system. The results are analyzed and discussed.

Counterexamples and uniqueness for [formula omitted] oblique derivative problems

Harmonic functions defined in Lipschitz domains of the plane that have gradient nontangentially in L 2 and have nonnegative oblique derivative almost everywhere on the boundary with respect to a continuous transverse vector field are shown to be constant. Explicit examples that have almost everywhere vanishing oblique derivative are constructed when L 2 is replaced by L p , p < 2 . Explicit examples with vanishing oblique derivative are constructed when p ⩽ 2 and the continuous vector field is replaced by large perturbations of the normal vector field. Optimal bounds on the perturbation, depending on p ⩽ 2 and the Lipschitz constant, are given which imply that only the constant solution has nonnegative oblique derivative almost everywhere. Examples are constructed in higher dimensions and the Fredholm properties of certain nonvariational layer potentials discussed.

THE BLACK HOLE HORIZON AS A DYNAMICAL SYSTEM

Interactions between outgoing Hawking particles and ingoing matter are determined by gravitational forces and Standard Model interactions. In particular, the gravitational interactions are responsible for the unitarity of the scattering against the horizon, as dictated by the holographic principle, but the Standard Model interactions also contribute, and understanding their effects is an important first step towards a complete understanding of the horizon's dynamics. The relation between in- and outgoing states is described in terms of an operator algebra. In this contribution, in which earlier results are rederived and elaborated upon, we first describe the algebra induced on the horizon by U(1) vector fields and scalar fields, including the case of an Englert–Brout–Higgs mechanism, and a more careful consideration of the transverse vector field components. We demonstrate that, unlike classical black holes, the quantized black hole has on its horizon an imprint of its (recent) past history, i.e., quantum hair. The relation between in- and outgoing states depends on this imprint. As a first step towards the inclusion of non-Abelian interactions, we then compute the effects of magnetic monopoles both in the in-states and in the out-states. They completely modify, and indeed simplify, our algebra.

TheQtdistribution of the Breit current hemisphere in DIS as a probe of small-xbroadening effects

We study the distribution 1/sigma dsigma/dQt, where Qt is the modulus of the transverse momentum vector, obtained by summing over all hadrons, in the current hemisphere of the DIS Breit frame. We resum the large logarithms in the small Qt region, to next-to--leading logarithmic accuracy, including the non-global logarithms involved. We point out that this observable is simply related to the Drell-Yan vector boson and predicted Higgs Qt spectra at hadron colliders. Comparing our predictions to existing HERA data thus ought to be a valuable source of information on the role or absence of small-x (BFKL) effects, neglected in conventional resummations of such quantities.

Transverse Vector Vertex Function and Transverse Ward–TakahashiRelations in QED

The transverse vector vertex function in momentum space infour-dimensional QED is derived in terms of a set of transverseWard–Takahashi relations for the vector and the axial-vectorvertices in the case of massless fermion. It is demonstratedexplicitly that the transverse vector vertex function derived thisway to one-loop order leads to the same result as one obtained inperturbation theory. This provides a basic approach to determinethe transverse part of basic vertex function from the symmetryrelations of the system.

On scalar curvature in lightlike geometry

We introduce the concept of induced scalar curvature of a class C [ M ] of lightlike hypersurfaces ( M , g , S ( TM ) ) , of a Lorentzian manifold, such that M admits a canonical screen distribution S ( TM ) , a canonical lightlike transversal vector bundle and an induced symmetric Ricci tensor. We prove that there exists such a class C [ M ] of a globally hyperbolic warped product spacetime [J.K. Beem, P.E. Ehrlich, K.L. Easley, Global Lorentzian Geometry, 2nd edition, Marcel Dekker, Inc. New York, 1996, MR1384756 (97f:53100)] of general relativity. In particular, we calculate the scalar curvature of a member of C [ M ] in a globally hyperbolic spacetime of constant curvature, supported by an example.

A40. Anisotropic response of cardiac myocytes to cyclic strain

Biomechanical forces play a crucial role in cardiac muscle adaptation and disease. Relevant mechanical elements include tensile, compressive and shear stress. Therefore the hypothesis is that the direction and rate of cyclic mechanical strain regulate protein phosphorylation and localization. Flexcell stretch device administers cyclic strain of desired amplitude and frequency to cultured neonatal rat myocytes oriented by microfabricated grooves to a transverse or longitudinal uniaxial force vector.

Addendum to "Helicity conservation in gauge boson scattering at high energy"

In a previous paper we have established that for any two-body process involving even numbers of transverse vector bosons and gauginos, the dominant asymptotic amplitudes obey helicity conservation (HC); i.e. the sum of the helicities of the two incoming particles equals to the sum of the helicities of the two outgoing ones. This HC has been proved to all orders in MSSM, provided $(s, |t|,|u|)$ are much larger than all masses in the model; but only to leading 1-loop logarithmic order in SM. In the present addendum, the validity of HC is extended to all two-body processes. Renormalizability is crucial for the HC validity, while all known anomalous couplings violate it.