There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

This chapter introduces the finite element method (FEM) as a tool for solution of classical electromagnetic problems. Although we discuss the main points in the application of the finite element method to electromagnetic design, including formulation and implementation, those who seek deeper understanding of the finite element method should consult some of the works listed in the bibliography section.

Introduction to the Finite Element Method

This chapter introduces the subject of statistical pattern recognition (SPR). It starts by considering how features are defined and emphasizes that the nearest neighbor algorithm achieves error rates comparable with those of an ideal Bayes’ classifier. The concepts of an optimal number of features, representativeness of the training data, and the need to avoid overfitting to the training data are stressed. The chapter shows that methods such as the support vector machine and artificial neural networks are subject to these same training limitations, although each has its advantages. For neural networks, the multilayer perceptron architecture and back-propagation algorithm are described. The chapter distinguishes between supervised and unsupervised learning, demonstrating the advantages of the latter and showing how methods such as clustering and principal components analysis fit into the SPR framework. The chapter also defines the receiver operating characteristic, which allows an optimum balance between false positives and false negatives to be achieved.

Statistical Pattern Recognition

This study provides a bibliographic review in the broad field of green composites seeking-out for materials with a potential to be applied in the near future on automotive body panels. Hereupon, materials deriving from renewable resources will be preferred as opposed to the exhaustible fossil products. With the technical information of bio-polymers and natural reinforcements a database was created with the mechanical performance of several possible components for the prospect green composite. Following the review, an assessment is performed where aspects of suitability for the candidate elements in terms of mechanical properties are analyzed. In that section, renewable materials for matrix and reinforcement are screened accordingly in order to identify which hold both adequate strength and stiffness performance along with affordable cost so as to be a promising proposal for a green composite.

Green composites: A review of adequate materials for automotive applications

http://jultika.oulu.fi/files/nbnfi-fe2017112150815.pdf

One-part alkali-activated materials : a review

Natural frequency of functionally graded (F.G.) rectangular plate is carried out by using second-order shear deformation theory (SSDT). The material properties of functionally graded rectangular plates, except the Poisson's ratio, are assumed to vary continuously through the thickness of the plate in accordance with the exponential law distribution. The equations of motion are obtained by energy method. Numerical results for functionally graded plates are given in dimensionless graphical forms and the effects of material properties on natural frequency are determined.

https://iopscience.iop.org/article/10.1088/1757-899X/17/1/012008/pdf

Natural Frequency of F.G. Rectangular Plate by Shear Deformation Theory

This work was conducted as part of the Aircraft Reliability Through Intelligent Materials Application (ARTIMA) European Union project. It presents a case study of damage detection in a curved carbon-fibre reinforced panel with two omega stiffeners which was investigated using ultrasonic lamb waves. The statistical technique of outlier analysis was used here as a way of pre-processing experimental data prior to damage classification. Multilayer perceptron neural networks were used here for both classification and regression problems of damage detection. It was then investigated whether using wavelet analysis to perform prior wavelet decompositions of experimental data could facilitate damage classification.

/pdf/damage-localisation-in-a-stiffened-composite-panel-47lduvwk9r.pdf

Damage localisation in a stiffened composite panel

Structural health monitoring (SHM) system is a method of evaluating and monitoring structural health. It has been widely applied in various engineering sectors due to its ability to respond to adverse structural changes, improving structural reliability and life cycle management. Various methods in SHM are presented in this chapter such as acoustic emission, ultrasonic, and thermal imaging. The advantages of SHM and nondestructive testing method are compared. In addition, SHM applications in the aerospace, civil, and energy sectors are discussed thoroughly. Furthermore, special attention is given to composite material that employs the SHM system in recent research investigations. Anisotropic composite materials can be divided into three different fiber reinforcements, namely synthetic, natural, and hybrid fibers. SHM applications in composites and the recent trends are explored. In approaching the fourth industrial revolution, SHM as a sensor for civil engineering applications is proposed due to its capability of interacting with the environment. Furthermore, the intention to enhance sensor capability to handle more functions is also discussed. At the end of this chapter, recent issues are highlighted to emphasize the technology and SHM potential as an energy harvester in the near future.

Structural health monitoring of biocomposites, fibre-reinforced composites, and hybrid composite

Various methods of flow control for enhanced aerodynamic performance have been developed and applied to enhance and control the behavior of aerodynamic components. The use of Coanda effect for the enhancement of circulation and lift has gained renewed interest, in particular with the progress of CFD. The present work addresses the influence, effectiveness, and configuration of Coanda-jet fitted aerodynamic surface for improving lift and , specifically for S809 airfoil, with a view on its incorporation in the wind turbine. A simple two-dimensional CFD modeling using - turbulence model is utilized to reveal the key elements that could exhibit the desired performance for a series of S809 airfoil configurations. Parametric study performed indicates that the use of Coanda-jet S809 airfoil can only be effective in certain range of trailing edge rounding-off radius, Coanda-jet thickness, and momentum jet size. The location of the Coanda-jet was found to be effective when it is placed close to the trailing edge. The results are compared with experimental data for benchmarking. Three-dimensional configurations are synthesized using certain acceptable assumptions. A trade-off study on the S809 Coanda configured airfoil is needed to judge the optimum configuration of Coanda-jet fitted Wind-Turbine design.

/pdf/computational-study-on-the-aerodynamic-performance-of-wind-1kftqh1ut0.pdf

Computational Study on the Aerodynamic Performance of Wind Turbine Airfoil Fitted with Coandă Jet

In this paper, an intelligent knowledge‐based system (KBS) capable of assisting aircraft mechanics and engineers to deal with fault diagnosis of the turbo‐prop aircraft engine is presented. The KBS intelligent jet engine trouble‐shooting system (IJETSS) employs expert knowledge to act in a way similar to that of a human expert in an aircraft maintenance field by using if‐then rule‐based system. The major aim of the KBS of IJETSS is to generate rapid and precise engine fault diagnosis that can simulate the work of experienced aircraft maintenance mechanics and engineers. The developed system can also be useful for the inexperienced aircraft mechanics and engineers and can be used for training module for them.

/pdf/a-computer-based-intelligent-system-for-fault-diagnosis-of-1m1v42cgjx.pdf

Faizal Mustapha

Papers

Natural Frequency of F.G. Rectangular Plate by Shear Deformation Theory

Damage localisation in a stiffened composite panel

Structural health monitoring of biocomposites, fibre-reinforced composites, and hybrid composite

Computational Study on the Aerodynamic Performance of Wind Turbine Airfoil Fitted with Coandă Jet

A computer‐based intelligent system for fault diagnosis of an aircraft engine