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Review Article 

Photon Mass

SA Orlov

Abstract

The atomic structure is presented on the basis of the theory of vortex gravitation. The feasibility and calculation of the values of the density and mass of electromagnetic particles are proposed. A calculation is made, which proves that the photon must have mass. In the calculations, some physical characteristics of electromagnetic particles that are accepted by modern physics are refuted.

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Review Article 

Low-Cycle-Fatigue Failures of Solder Material in Electronics Packaging: Analytical Modeling Enables to Predict and Possibly Prevent Them-Review

E Suhir

Abstract

This review paper is based mostly on the author's recent publications and addresses the application of analytical ("mathematical") predictive modeling to understand the physics and mechanics of the behavior and performance of solder materials and solder joint interconnections employed in IC devices. The emphasis is on the design for reliability and, first of all, on the prediction of the thermal stresses and strains in solder joint interconnections of electronic products.

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Original Research Article 

Towards an Airfoil Catalogue for Wind Turbine Blades at IDR/UPM Institute with OpenFOAM

F Sorribes Palmer, L Donisi, S Pindado, O Gomez Ortega and M Ogueta Gutierrez

Abstract

A methodology to efficiently simulate wind tunnel tests of several airfoils with OpenFOAM has been developed in this work. This methodology bridges OpenFOAM capabilities with MATLAB post-processing in order to analyze efficiently the performance of wind turbine airfoils at any angle of attack. This technique has been developed to reduce the cost, in terms of time and resources, of wind tunnel campaigns on wind turbine blade airfoils.

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Original Research Article 

Active Flutter Suppression of Stochastic Airfoil with Uncertain Pitch Stiffness

Wu Cunli and Tong Fang

Abstract

Flutter suppression of a typical airfoil with uncertain pitch stiffness by feedback control of its trailing-edge surface is analyzed. The pitch stiffness coefficient is modeled by a quadratic function of a bounded random variable with the bounded probability density function, thus the airfoil system becomes a stochastic structure depending on its random parameter.

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Original Research 

A Thorough Study on the Temporal Accuracy of ALE-URANS Solvers with and Without Respecting Geometric Conservation Law

A Mosahebi and E Laurendeau

Abstract

The importance of satisfying the Geometric Conservation Law (GCL) to maintain second-order temporal accuracy for flow evaluations on dynamic grids are investigated for a Finite Volume Method (FVM)-based dual-time stepping Unsteady Reynolds-Averaged Navier-Stokes (URANS) solver.

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Research Article 

Occupational and Residential Exposures to Infrasound and Low Frequency Noise in Aerospace Professionals: Flawed Assumptions, Inappropriate Quantification of Acoustic Environments, and the Inability to Determine Dose-Response Values

Mariana Alves-Pereira and Huub HC Bakker

Abstract

Professionals within the aerospace industry are often required to remain within acoustic environments characterized by a predominance of low frequency and infrasound components. Safety-and-health-in-the-workplace officials are mindful of the threat these extreme environments can pose to the hearing function.

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Original Research Article 

Dynamic Response and Vibration Control of a Planar Tensegrity Beam under El Centro Seismic Excitation

Xiaodong Feng

Abstract

Tensegrity systems are mechanical structures made of struts in compression, kept in stable equilibrium by a network of cables in tension, they are a class of mechanical structures which are highly controllable.

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Research Article 

Critically Evaluating Mechanics of Structure Genome-Based Micromechanics Approach

Hamsasew M Sertse, Liang Zhang and Wenbin Yu

Abstract

The objective of this paper is to critically evaluate the accuracy and efficiency of a general-purpose micromechanics approach based on the Mechanics of Structure Genome (MSG), when it is applied to the constitutive modeling of 3D structures.

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Research Article 

On the Dynamics of Tensegrity Bridges

Gerardo Carpentieri and Robert E Skelton

Abstract

This paper describes the nonlinear dynamics of planar tensegrity bridges designed for minimal mass. The three-dimensional bridge benefits by the planar analysis in the most important manner relating to topology of material. We start with the minimal mass bridge, counting both structural mass and deck mass, and then derive the nonlinear dynamics to study dynamic behavior of the minimal mass bridge.

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Research Article 

Instrumental Methodology for the Study of Vestibule-Ocular Reflex Associated to Spatial Disorientation Induced by Random Movements of a Human Gyroscope

Geovanny Palomino Roldan, R Mora Martinez and Ernesto Suaste Gomez

Abstract

The present methodology describes a register system of ocular and head movements in a human gyroscope, whose purpose was to observe the behavior of the vestibulo-ocular reflex. Two stages compound the system: a video-oculography element, which quantifies eye movements.

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Original Article 

Numerical Simulation of Aerodynamic Penalties of the DHC-6 Twin Otter Aircraft in Heavy Rain

Benyin Lv, Yihua Cao and Zhenlong Wu

Abstract

Numerical simulations are conducted on the DHC-6 Twin Otter wing and horizontal tailplane to explore the aerodynamic penalties that affect airfoil performance in heavy rain conditions. An Eulerian-Lagrangian two-phase flow method is used to simulate the aerodynamic performance of the wing under rainfall conditions.

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Original Article 

Effects of a Full Scale Aircraft Immersed within a Large Aviation-Fuel Fire in Crosswind on the Flame Shape - A Numerical Study

GD Wang and HY Wang

Abstract

Large Eddy Simulation combined with an Eddy Dissipation Concept (EDC) combustion model shows the feasibility for simulations of a full scale aircraft immersed within a large aviation-fuel fire in a moving fluid medium. Coupling between the condensed fuel and gas phases allows investigating the roles of the wind speed on the burning rate of condensed fuel, and consequently, the heat release rate.

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ORIGINAL ARTICLE 

A Modified Particle Filter for SINS/SAR Integrated Navigation

Haifeng Yan, Bingbing Gao, Yongmin Zhong, Shesheng Gao and Chengfan Gu

Abstract

This paper presents a modified particle filter for SINS/SAR (Strap-down Inertial Navigation System/Synthetic Aperture Radar) integrated navigation. This method is developed by adopting Markov Chain Monte Carlo (MCMC) moves to the particle regularization process. It combines local resampling with MCMC moves to prevent particle degeneracy and also guarantee that the resultant particles are in the same distribution as probability distribution function, without causing extra noise on state estimate.

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ORIGINAL ARTICLE 

Model Predictive Filtering Based Neural Networks for GPS GDOP Approximation

Yi Yang, Shesheng Gao, Yongmin Zhong and Chengfan Gu

Abstract

This paper presents a new method to calculate the geometric dilution of precision (GDOP) of GPS by incorporating the concept of model predictive filtering in the training process of neural networks to learn the relationship between GDOP and the azimuth and elevation of satellite. This method overcomes the shortcomings of the traditional back propagation neural networks, such as the slow convergence speed and easily falling into local minimum.

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