Zero Displacement Research Articles

Elastic Stress Analysis for Case of Corrugated Fiberboard Box Shape Applied Uniform Compression in Upper and Lower Edges. On Standing Plate Approxiluate Analysis Method of Square Tube for Upper and Lower Supported Edges of Zero Displacement.

For fundamental deformation of the case of the corrugated fiberboard box shape under uniform compression(1N/mm2), it was discussed that side plate deformation of its case was simulated as the zero displacement of the breadth direction on upper and lower edges. Then an elastic stress formulation, for their side plates(breadth L and height h)was expressed. Also, from this formulation, the stress analysis of its plate was performed and its characteristic behavior was done obviously. In the tange y=3h/8∼5h/8(y:diatance from the center in the height direction), the normal stress σx in the breadth direction for the plate decreases with the increases of distance(x-L/2)from the plate center in the breadth direction, and in the range y=3h/8∼5h/8, increases roughly. In y=h/2∼3h/4 range, absolute value σy of the normal stress in the height direction for the plate decrease roughly with the in crease of(x-L/2), and in range y>3h/4, the constant σy appears about the x=L/2. Also, in the range h/2<y&lnE;3h/4, the absolute shear stress txy increases initially and next decreases with the increase of(x-L/2), and in the range y>3h/4 becomes inversely.

Determination of initial cable forces in prestressed concrete cable-stayed bridges for given design deck profiles using the force equilibrium method

The determination of initial cable forces in a prestressed concrete cable-stayed bridge for a given vertical profile of deck under its dead load is an important but difficult task that affects the overall design of the bridge. A new method utilizing the idea of force equilibrium is presented in this paper for their determination. The method can easily account for the effect of prestressing and the additional bending moments due to the vertical profile of the bridge deck. It is much more rational and simple than the traditional “zero displacement” method, and it is able to achieve bending moments in the bridge deck approaching those in a continuous beam over rigid simple supports.

An error estimation measure in the direct BEM formulation by the external Somigliana's identity

In this paper we consider a physical interpretation of Somigliana's identities as the basis of the formulation of the direct Boundary Element Method as well as its error estimation measure. While Somigliana's internal identity gives the solution to a given boundary value problem for a domain D (+), the external identity of Somigliana gives zero stress and displacement for the domain D (−) complementary to D (+) in the infinite region. The BEM error equally affects the accuracy of both identities and error estimation for the complementary domain D (−) is adopted for that for the original domain D (+). We propose the domain integral for the strain energy in the complementary domain D (−) as an error measure which, in turn, is converted to a boundary integral over the boundary of D (−). The individual contribution to this boundary error integral comes from each boundary element and it serves as an error measure for each boundary element, which can be used in an adaptive re-meshing strategy. Numerical examples strongly support our error measure and adaptive re-meshing strategy.

Evolution of extensional styles at the southern termination of the Nordland Ridge, Mid-Norway: a response to variations in coupling above Triassic salt

The southern termination of the Nordland Ridge, mid-Norway exhibits variations in extensional style which can be attributed to differing degrees of coupling between pre-salt ‘basement’ and post-salt ‘cover’ strata. South of the Nordland Ridge, Jurassic and Cretaceous extension is distributed relatively uniformly over the 80 km wide Halten Terrace. Further to the north the zone of extension narrows to less than 40 km and the majority of the extension is taken up on the Revfallet Fault, which separates the Dønna Terrace from the Nordland Ridge. Displacement on the Revfallet Fault, at basement level, increases progressively from its zero displacement tip to a maximum of 7 km, 60 km to the north. At low displacements, extension in the cover is decoupled from the basement extension and vertical level changes are accommodated by monoclinal flexure. As displacement on the Revfallet Fault increases, the degree of basement-cover coupling increases and a much closer spatial link between deformation in the basement and in the cover is evident. This progressive increase in degree of coupling is characterized by increased footwall uplift and decreased extension in the cover away from the master fault. The degree of basement-cover coupling can also be shown to vary not only with displacement but also with time, in response to variable strain rates. Initial extension during the Jurassic was predominantly decoupled and occurred over 50 Ma period. After 40 50 Ma of relative quiescence, the major extensional episode occurred within a comparatively short 10 Ma period in the mid-Cretaceous. This later period of rapid extension requires strain rates at least an order of magnitude greater than those of the Jurassic. The results of this study have led to significant changes in the regional tectono-stratigraphic model.

Vibration of composite plates with internal supports

The free vibration of rectangular laminated composite plates with arbitrary support conditions along the edges, internal line supports and discrete point supports are studied using the Rayleigh-Ritz method. Polynomial approximation functions are selected to satisfy all essential boundary conditions along the edges of the plate and to vanish along line supports parallel to the co-ordinate axes. Straight line supports at an angle from the co-ordinate axes and curved line supports are modeled by introducing several point supports along the line. Zero displacement constraints at the point support locations are enforced using the Lagrange multiplier technique. The plate constitutive equations are expressed in terms of stiffness invariants and the fundamental natural frequency is maximized by selecting the appropriate lay-up. Several examples are presented to illustrate the versatility of the approach and provide results not previously available. The influence of the number of plies in the laminate, lay-up, material properties and plate aspect ratios are investigated.

Zero Modes and Displacement Symmetry in Electrodynamics

The global residual gauge symmetry of electrodynamics, the displacement symmetry, is discussed within the Weyl-gauge formulation and used to characterize different phases of the Maxwell field coupled to matter. Unlike other global symmetries, the displacement symmetry, in the absence of interactions or in the weak coupling regime, is realized in the Nambu-Goldstone mode. The displacement symmetry will be shown to be realized in the Wigner-Weyl mode in the plasma and superconducting states; this discussion develops a novel perspective of the plasma oscillations. Other examples are the states of the Schwinger model and the non-perturbative phase of the Abelian Higgs model. The Higgs mechanism is interpreted as formation of a phase with a high degree of symmetry. Finite photon mass and shielding of external fields will be recognized as the characteristic properties of these symmetric phases.

A 3-D raytracer for teleseismic body-wave arrival times

Abstract In this article, we present a method for determining the minimum time ray path from a planar wavefront at depth to a fixed point at the surface through a 3-D heterogeneous velocity structure. The program is based on the two point raytracer of Prothero et al. (1988), with a modification to use odd quarter-cycles of sinusoids to distort the rays. These functions produce zero displacement at the fixed receiver but non zero displacement at the wavefront. This allows the raytracer to explore a wide variety of ray paths starting at different points on the wavefront, while the rays leaving the wavefront remain normal to it. To find the minimum time path, amplitudes of these functions are systematically perturbed using the simplex algorithm. The approach is analogous to using a Fourier series to fit a curve with specific properties at each end. Development of this raytracer was motivated by the desire to model our observations of large perturbations in the bearings and phase velocities of teleseismic P waves recorded in Long Valley caldera, California. These observations clearly show the inadequacy of 1-D raytracing in regions having complex, three-dimensionally varying velocity structure. This raytracer provides a basic tool with which to study the effects of ray bending on tomographic results from these kinds of environments.

Partial Pole and Zero Displacement by Cascade Connection

Recent interpolation results for rational matrix functions with incomplete data are applied to solve a problem of shifting a part of the poles and the zeros of a given rational matrix function, keeping the other poles and zeros unchanged and the McMillan degree as small as possible.

Motion compensating field interpolation using a hierarchically structured displacement estimator

A motion compensating field interpolation algorithm is presented, which allows to interpolate several fields between every two transmitted fields of a digital television sequence. Using the model of translatorily displaced objects, a hierarchically structured displacement estimator is applied to cope with relatively large displacements. It provides a displacement vector with integer components for each picture element of the fields to be interpolated. A change detector is used to assure zero displacement vectors in unchanged areas. A two-coefficient spatio-temporal filter interpolates each picture element of the fields to be interpolated. By experimental evaluations, the model of pure translatorily displaced objects has proven to be sufficient to approximate many kinds of motion. The presented interpolation technique allows the unblurred reconstruction of omitted fields of television sequences, widely preserving the natural impression of motion.

Structural variation in wollastonite and bustamite

AbstractThe structures of bustamite and the poly-types of wollastonite are shown to be derived from variations in the stacking sequence of a single type of structural unit. This structural unit is a column of unit cells of wollastonite along the b-axis and is bounded by (100) and (001) planes (P1̄ cell); these units may be stacked together along [100] and [001] with either zero displacement between successive units, or a relative displacement of 1/2[010]. Regular stacking sequences give rise to the ordered structures of wollastonite polytypes and of bustamite, while the transformations between these structures proceed by the propagation of line defects with Burgers vectors of 1/2[010] which thus change the stacking sequence of the structural units.

The Causes of Zero Displacement and Deflection Hysteresis in Moving-Coil Galvanometers

The Causes of Zero Displacement and Deflection Hysteresis in Moving-Coil Galvanometers