Approximate expressions and the relationship between pyramidalization (out-of-plane deformation) characteristics of trigonal centers

2012 ◽  
Vol 33 (27) ◽  
pp. 2173-2179 ◽  
Author(s):  
Sergey P. Gavrish
Keyword(s):  
Plane Deformation ◽  
Deformation Characteristics ◽  
Out Of Plane ◽  
The Relationship ◽  
Approximate Expressions

Wrinkling analysis and control of rectangular space membrane

2016 ◽  
Vol 231 (11) ◽  
pp. 1959-1969
Author(s):  
Mingjun Liu ◽  
Jin Huang ◽  
Yali Wang
Keyword(s):  
Control Method ◽  
Plate Theory ◽  
Plane Deformation ◽  
The Finite Element Method ◽  
Membrane Structures ◽  
Wrinkling Analysis ◽  
Out Of Plane ◽  
And Control ◽  
The Relationship ◽  
Main Factor

Wrinkling, a common phenomenon found in space membrane structures, is the main factor affecting the performance, stability, and dynamic characteristics of these membrane structures. This article presents an active control method to improve the surface accuracy of membrane structures. A model of a thin rectangular membrane subjects to uniaxial uniform tensile stress is discussed. Initially, the relationship between the out-of-plane deformation of the wrinkles and the boundary conditions is built with the Föppl–Von Karman plate theory by introducing the slow varying Fourier series. Because vertical tensions perpendicular to the direction of the initial wrinkles are necessary to reduce these wrinkles, reasonable locations and magnitudes of these tensions are the key problems. The finite element method and variational principle method are used to solve this issue. Finally, a manufacturing error is added to the model as an initial defect, and the robustness of the controller is verified. Simulation results show that wrinkles are reduced quickly and effectively with the proposed method.

Dynamic stiffness formulation for the vibrations of stiffened plate structures with consideration of in-plane deformation

2017 ◽  
Vol 24 (20) ◽  
pp. 4825-4838 ◽  
Author(s):  
Xuewen Yin ◽  
Wenwei Wu ◽  
Kuikui Zhong ◽  
Hui Li
Keyword(s):  
Finite Element ◽  
Dynamic Stiffness ◽  
Plane Deformation ◽  
Element Model ◽  
The Finite Element Method ◽  
Plate Structures ◽  
Beam Elements ◽  
Stiffness Model ◽  
Out Of Plane ◽  
The Relationship

A dynamic stiffness method is presented for the vibrations of plate structures that are reinforced by eccentric stiffeners. The model incorporates both out-of-plane and in-plane deformations of the plates and the stiffeners. Based on the relationship between the forces and displacements along the common edges of the plate or beam elements, the dynamic stiffness formulae for the plate and the beam elements are derived, respectively. The globally assembled dynamic stiffness matrix is then obtained using the finite element method so that the dynamics of built-up stiffened plates can be readily addressed by using the present method. Compared to the conventional finite element model, the dynamic stiffness model can provide very accurate solutions using only one element over each uniform plate and beam member, regardless of its geometry.

Grain separation enhanced magnetic coercivity in Pt/Co multilayers.

1993 ◽  
Vol 51 ◽  
pp. 1038-1039 ◽  
Author(s):  
G.A. Bertero ◽  
R. Sinclair
Keyword(s):  
Remanent Magnetization ◽  
Strong Influence ◽  
Uniaxial Anisotropy ◽  
Magnetic Coupling ◽  
Recording Media ◽  
Magnetic Media ◽  
Signal To Noise ◽  
Out Of Plane ◽  
Longitudinal Recording ◽  
The Relationship

Pt/Co multilayers displaying perpendicular (out-of-plane) magnetic anisotropy and 100% perpendicular remanent magnetization are strong candidates as magnetic media for the next generation of magneto-optic recording devices. The magnetic coercivity, Hc, and uniaxial anisotropy energy, Ku, are two important materials parameters, among others, in the quest to achieving higher recording densities with acceptable signal to noise ratios (SNR). The relationship between Ku and Hc in these films is not a simple one since features such as grain boundaries, for example, can have a strong influence on Hc but affect Ku only in a secondary manner. In this regard grain boundary separation provides a way to minimize the grain-to-grain magnetic coupling which is known to result in larger coercivities and improved SNR as has been discussed extensively in the literature for conventional longitudinal recording media.We present here results from the deposition of two Pt/Co/Tb multilayers (A and B) which show significant differences in their coercive fields.

scholarly journals Characterization and ballistic performance of thin pre-damaged resin-starved aramid-fiber composite panels

2021 ◽  
pp. 004051752110134
Author(s):  
Cerise A Edwards ◽  
Stephen L Ogin ◽  
David A Jesson ◽  
Matthew Oldfield ◽  
Rebecca L Livesey ◽  
...  
Keyword(s):  
Fiber Composite ◽  
Plane Deformation ◽  
Ballistic Impact ◽  
Image Correlation ◽  
Composite Panel ◽  
Composite Panels ◽  
Micro Computed Tomography ◽  
Ballistic Performance ◽  
Low Level ◽  
Out Of Plane

Military personnel use protective armor systems that are frequently exposed to low-level damage, such as non-ballistic impact, wear-and-tear from everyday use, and damage during storage of equipment. The extent to which such low-level pre-damage could affect the performance of an armor system is unknown. In this work, low-level pre-damage has been introduced into a Kevlar/phenolic resin-starved composite panel using tensile loading. The tensile stress–strain behavior of this eight-layer material has been investigated and has been found to have two distinct regions; these have been understood in terms of the microstructure and damage within the composite panels investigated using micro-computed tomography and digital image correlation. Ballistic testing carried out on pristine (control) and pre-damaged panels did not indicate any difference in the V50 ballistic performance. However, an indication of a difference in response to ballistic impact was observed; the area of maximal local out-of-plane deformation for the pre-damaged panels was found to be twice that of the control panels, and the global out-of-plane deformation across the panel was also larger.

scholarly journals In-Process Measurement of Three-Dimensional Deformations Based on Speckle Photography

2021 ◽  
Vol 11 (11) ◽  
pp. 4981
Author(s):  
Andreas Tausendfreund ◽  
Dirk Stöbener ◽  
Andreas Fischer
Keyword(s):  
Evaluation Method ◽  
Process Analysis ◽  
Plane Deformation ◽  
Three Dimensional ◽  
Machining Process ◽  
Image Correlation ◽  
Speckle Photography ◽  
Process Measurement ◽  
Out Of Plane ◽  
Plane Deformations

In the concept of the process signature, the relationship between a material load and the modification remaining in the workpiece is used to better understand and optimize manufacturing processes. The basic prerequisite for this is to be able to measure the loads occurring during the machining process in the form of mechanical deformations. Speckle photography is suitable for this in-process measurement task and is already used in a variety of ways for in-plane deformation measurements. The shortcoming of this fast and robust measurement technique based on image correlation techniques is that out-of-plane deformations in the direction of the measurement system cannot be detected and increases the measurement error of in-plane deformations. In this paper, we investigate a method that infers local out-of-plane motions of the workpiece surface from the decorrelation of speckle patterns and is thus able to reconstruct three-dimensional deformation fields. The implementation of the evaluation method enables a fast reconstruction of 3D deformation fields, so that the in-process capability remains given. First measurements in a deep rolling process show that dynamic deformations underneath the die can be captured and demonstrate the suitability of the speckle method for manufacturing process analysis.

Inverse algorithm for out-of-plane deformation in shearography

2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Shuangle Wu ◽  
Fangyuan Sun ◽  
Haotian Xie ◽  
Qihan Zhao ◽  
Peizheng Yan ◽  
...  
Keyword(s):  
Plane Deformation ◽  
Inverse Algorithm ◽  
Out Of Plane

The Allocating Point Solution for the Out-of-Plane Stability of Arches with the Double Symmetry Axis Section

2010 ◽  
Vol 29-32 ◽  
pp. 1313-1316
Author(s):  
Yu Ji Chen
Keyword(s):  
Governing Equation ◽  
Spline Function ◽  
Symmetry Axis ◽  
Plane Deformation ◽  
Point Method ◽  
Out Of Plane ◽  
Point Solution ◽  
Double Symmetry ◽  
Paper Method

In order to study the buckling mechanics behaviour of the out-of-plane stability of arches with the double symmetry axis section, by mean of potential variational theories, considering the out-of-plane deformation of arches, the out-of-plane stability governing equation of arches was obtained. The problem was solved by the spline function allocating point method. An example was calculated with this paper method. It is shown by comparing the result of this paper with the others that the paper method is reliable and accurate.

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