Symmetry-Itemized Enumeration of Cubane Derivatives as Three-Dimensional Entities by the Elementary-Superposition Method of the USCI Approach

2012 ◽  
Vol 85 (7) ◽  
pp. 811-821 ◽  
Author(s):  
Shinsaku Fujita
Keyword(s):  
Three Dimensional ◽  
Superposition Method ◽  
Usci Approach

Three-Dimensional Green’s Functions in Anisotropic Elastic Bimaterials With Imperfect Interfaces

2003 ◽  
Vol 70 (2) ◽  
pp. 180-190 ◽  
Author(s):  
E. Pan
Keyword(s):  
Green's Functions ◽  
Green’S Functions ◽  
Three Dimensional ◽  
Imperfect Interface ◽  
Boundary Integral ◽  
Stress Fields ◽  
Superposition Method ◽  
Interface Conditions ◽  
Complementary Part ◽  
Anisotropic Elastic

In this paper, three-dimensional Green’s functions in anisotropic elastic bimaterials with imperfect interface conditions are derived based on the extended Stroh formalism and the Mindlin’s superposition method. Four different interface models are considered: perfect-bond, smooth-bond, dislocation-like, and force-like. While the first one is for a perfect interface, other three models are for imperfect ones. By introducing certain modified eigenmatrices, it is shown that the bimaterial Green’s functions for the three imperfect interface conditions have mathematically similar concise expressions as those for the perfect-bond interface. That is, the physical-domain bimaterial Green’s functions can be obtained as a sum of a homogeneous full-space Green’s function in an explicit form and a complementary part in terms of simple line-integrals over [0,π] suitable for standard numerical integration. Furthermore, the corresponding two-dimensional bimaterial Green’s functions have been also derived analytically for the three imperfect interface conditions. Based on the bimaterial Green’s functions, the effects of different interface conditions on the displacement and stress fields are discussed. It is shown that only the complementary part of the solution contributes to the difference of the displacement and stress fields due to different interface conditions. Numerical examples are given for the Green’s functions in the bimaterials made of two anisotropic half-spaces. It is observed that different interface conditions can produce substantially different results for some Green’s stress components in the vicinity of the interface, which should be of great interest to the design of interface. Finally, we remark that these bimaterial Green’s functions can be implemented into the boundary integral formulation for the analysis of layered structures where imperfect bond may exist.

Analysis of Commercial Vehicle Thrust Rod Load Simulation

2015 ◽  
Vol 713-715 ◽  
pp. 159-163
Author(s):  
Guo Yu Feng ◽  
Wen Ku Shi ◽  
Jun Ke ◽  
Lu Lu Guo
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Time History ◽  
Prototype Model ◽  
Superposition Method ◽  
Adams Software ◽  
Lower Load ◽  
Multi Body ◽  
Load Simulation ◽  
Three Dimensional Space

In order to obtain the accurate thrust rod load, based on the theory of multi body dynamics, establish the complete vehicle virtual prototype model by using ADAMS software, the dynamic simulation of the thrust rod load time history. Combined with MATLAB software to build three-dimensional space pavement model with harmonic superposition method, obtaining the thrust rod load under different conditions, the simulation results show that, the vehicle loaded with uphill turn thrust rod by the load of the largest, and bear in various working upper thrust rod load than the lower load. Consistent with the experimental results, illustrate the modeling method is correct, can quickly and accurately obtain the thrust rod load.

A New Three-Dimensional Moving Timoshenko Beam Element for Moving Load Problem Analysis

2020 ◽  
Vol 142 (3) ◽  
Author(s):  
Yan Xu ◽  
Weidong Zhu ◽  
Wei Fan ◽  
Caijing Yang ◽  
Weihua Zhang
Keyword(s):  
Dynamic Analysis ◽  
Coordinate System ◽  
Timoshenko Beam ◽  
Moving Load ◽  
Three Dimensional ◽  
Beam Element ◽  
Superposition Method ◽  
Reference Coordinate System ◽  
Current Formulation ◽  
Timoshenko Beam Element

Abstract A new three-dimensional moving Timoshenko beam element is developed for dynamic analysis of a moving load problem with a very long beam structure. The beam has small deformations and rotations, and bending, shear, and torsional deformations of the beam are considered. Since the dynamic responses of the beam are concentrated on a small region around the moving load and most of the long beam is at rest, owing to the damping effect, the beam is truncated with a finite length. A control volume that is attached to the moving load is introduced, which encloses the truncated beam, and a reference coordinate system is established on the left end of the truncated beam. The arbitrary Lagrangian–Euler method is used to describe the relationship of the position of a particle on the beam between the reference coordinate system and the global coordinate system. The truncated beam is spatially discretized using the current beam elements. Governing equations of a moving element are derived using Lagrange’s equations. While the whole beam needs to be discretized in the finite element method or modeled in the modal superposition method (MSM), only the truncated beam is discretized in the current formulation, which greatly reduces degrees-of-freedom and increases the efficiency. Furthermore, the efficiency of the present beam element is independent of the moving load speed, and the critical or supercritical speed range of the moving load can be analyzed through the present method. After the validation of the current formulation, a dynamic analysis of three-dimensional train–track interaction with a non-ballasted track is conducted. Results are in excellent agreement with those from the commercial software simpack where the MSM is used, and the calculation time of the current formulation is one-third of that of simpack. The current beam element is accurate and more efficient than the MSM for moving load problems of long three-dimensional beams. The derivation of the current beam element is straightforward, and the beam element can be easily extended for various other moving load problems.

Stiffness of an arbitrarily crowned roller compressed between two plates

2003 ◽  
Vol 217 (5) ◽  
pp. 375-384 ◽  
Author(s):  
T. L. Horng ◽  
S. H. Ju
Keyword(s):  
Finite Element ◽  
Fourth Order ◽  
Three Dimensional ◽  
Cylindrical Part ◽  
Superposition Method ◽  
Finite Element Analyses ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

This paper derives a stiffness equation for the arbitrarily crowned roller compressed between two plates. The roller is first divided into three parts: two crowned parts and one cylindrical part. The superposition method is introduced to obtain the roller stiffness. Three-dimensional finite element analyses were used to validate the accuracy of the stiffness equation, in which rollers with circular, quadratic, cubic, fourth-order power and exponential profiles were analysed. Comparisons with finite element results indicate that the accuracy of the stiffness equation derived in this paper is acceptable.

The Analysis and Application on the Typhoon-Induced Vibration Control of the Wind Turbine with a Pendulum Damper

2013 ◽  
Vol 773 ◽  
pp. 193-198 ◽  
Author(s):  
Jing Li ◽  
Jian Yun Chen ◽  
Xiao Bo Chen
Keyword(s):  
Wind Turbine ◽  
Three Dimensional ◽  
Element Model ◽  
Dynamic Responses ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Superposition Method ◽  
Strong Wind ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

As a kind of high-rise structure, the offshore wind turbine is sensitive to wind load; it can generate strong dynamic responses to the excitation of typhoon. In this paper, a three-dimensional finite element model of offshore wind turbine is established with ADINA, responses under strong wind excitation are numerically simulated and performed subsequently. The fluctuating wind velocity time series are simulated by the method of HSM (harmony superposition method). Based on the modal and tine-history analyses of the structures together with self-vibration character, the pendulum damper is employed to control the resulting undesirable vibrations that are induced by wind. With the damper installed, the displacement and acceleration of the tower are reduced by as much as 40% using 1% of the total effective mass.

The Three-Dimensional Infinite Space and Half-Space Green's Functions for Orthotropic Materials

2014 ◽  
Vol 31 (1) ◽  
pp. 21-28
Author(s):  
V.-G. Lee
Keyword(s):  
Green’S Function ◽  
Half Space ◽  
Green's Function ◽  
Green's Functions ◽  
Green’S Functions ◽  
Three Dimensional ◽  
Mathematical Concept ◽  
Orthotropic Materials ◽  
Superposition Method ◽  
Infinite Domain

ABSTRACTCommon materials, ranging from natural wood to modern composites, have been recognized as ortho-tropic materials. The elastic properties of such materials are governed by nine elastic constants. In this paper the complete set of Green's functions for an infinite medium and a half space is given, which were not reported completely before. Analytic expressions for the infinite Green's functions are derived through the explicit form of the sextic equation given explicitly. For an orthotopic half space, the Green's function is derived by a superposition method. The mathematical concept is based on the addition of a complementary term to the Green's function in an orthotropic infinite domain to fulfill the boundary condition on the free surface. Both solutions are illustrated in certain directions to demonstrate the nature of orthotropy.

Effect of Drive Location on Vibro-Acoustic Characteristics of Submerged Double Cylindrical Shells with Damping Layers

2013 ◽  
Vol 387 ◽  
pp. 59-63
Author(s):  
Chao Zhang ◽  
De Jiang Shang ◽  
Qi Li
Keyword(s):  
Annular Plate ◽  
Cylindrical Shells ◽  
Three Dimensional ◽  
Plane Motion ◽  
Superposition Method ◽  
Annular Plates ◽  
Radiated Power ◽  
Modal Superposition Method ◽  
Viscoelastic Theory ◽  
Vibration And Sound Radiation

Based on the modal superposition method, the analytical model of vibration and sound radiation from submerged double cylindrical shells with damping layers was presented. The shells were described by the classical thin shell theory. The damping layers were described by three-dimensional viscoelastic theory. The annular plates, connecting the double shells, were analyzed with in-plane motion theory. For different drive locations of radial point force on the inner shell, the sound radiated power and the radial quadratic velocity of the model were calculated and analyzed. The results show that making the drive location near the annular plate helps to reduce the sound radiated power and radial quadratic velocity of model, and making the drive location far from the middle of model also helps to reduce the sound radiated power. The drive applied on the location of annular plate causes high similarity of vibrations from inner shell and outer shell.

scholarly journals Multifeature Fusion Detection Method for Fake Face Attack in Identity Authentication

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Haiqing Liu ◽  
Shiqiang Zheng ◽  
Shuhua Hao ◽  
Yuancheng Li
Keyword(s):  
Optical Flow ◽  
Facial Recognition ◽  
Three Dimensional ◽  
Identity Authentication ◽  
Joint Analysis ◽  
Svm Classifier ◽  
Detection Accuracy ◽  
Superposition Method ◽  
Three Dimensional Model ◽  
Replay Attack

With the rise in biometric-based identity authentication, facial recognition software has already stimulated interesting research. However, facial recognition has also been subjected to criticism due to security concerns. The main attack methods include photo, video, and three-dimensional model attacks. In this paper, we propose a multifeature fusion scheme that combines dynamic and static joint analysis to detect fake face attacks. Since the texture differences between the real and the fake faces can be easily detected, LBP (local binary patter) texture operators and optical flow algorithms are often merged. Basic LBP methods are also modified by considering the nearest neighbour binary computing method instead of the fixed centre pixel method; the traditional optical flow algorithm is also modified by applying the multifusion feature superposition method, which reduces the noise of the image. In the pyramid model, image processing is performed in each layer by using block calculations that form multiple block images. The features of the image are obtained via two fused algorithms (MOLF), which are then trained and tested separately by an SVM classifier. Experimental results show that this method can improve detection accuracy while also reducing computational complexity. In this paper, we use the CASIA, PRINT-ATTACK, and REPLAY-ATTACK database to compare the various LBP algorithms that incorporate optical flow and fusion algorithms.

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