Dielectric Properties of Textile Materials: Analytical Approximations and Experimental Measurements—A Review

Deciphering how the dielectric properties of textile materials are orchestrated by their internal components has far-reaching implications. For the development of textile-based electronics, which have gained ever-increasing attention for their uniquely combined features of electronics and traditional fabrics, both performance and form factor are critically dependent on the dielectric properties. The knowledge of the dielectric properties of textile materials is thus crucial in successful design and operation of textile-based electronics. While the dielectric properties of textile materials could be estimated to some extent from the compositional profiles, recent studies have identified various additional factors that have also substantial influence. From the viewpoint of materials characterization, such dependence of the dielectric properties of textile materials have given rise to a new possibility—information on various internal components could be, upon successful correlation, extracted by measuring the dielectric properties. In view of these considerable implications, this invited review paper summarizes various fundamental theories and principles related to the dielectric properties of textile materials. In order to provide an imperative basis for uncovering various factors that intricately influence the dielectric properties of textile materials, the foundations of the dielectrics and polarization mechanisms are first recapitulated, followed by an overview on the concept of homogenization and the dielectric mixture theory. The principal advantages, challenges and opportunities in the analytical approximations of the dielectric properties of textile materials are then discussed based on the findings from the recent literature, and finally a variety of characterization methods suitable for measuring the dielectric properties of textile materials are described. It is among the objectives of this paper to build a practical signpost for scientists and engineers in this rapidly evolving, cross-disciplinary field.

In Memoriam: Professor Pavel Leonidovich Kirillov (20.08.1927 08.10.2021)

Professor Pavel L. Kirillov has died on October 8th, 2021, on his 95th year after a life as a husband, father, and an internationally renowned scientist, researcher, and educator in the field of nuclear engineering, thermalhydraulics, heat transfer, and two-phase flow. He was a passionate and dedicated in everything, what he has done and leaves an incredible legacy to the profession. He was born on August 20th, 1927 in Russia, and received his M.A.Sc. degree in thermal physics in 1950 (Moscow Power-Engineering Institute (MPEI) (МосковскийЭнергетическйИнститут (МЭИ)), Faculty of Physics and Power Engineering (Физико-ЭнергетическийФакультет), Ph.D. and Doctor of Technical Sciences degrees in 1959 and 1969, respectively. Professor Pavel Leonidovich Kirillov was a respected technical leader, mentor, and friend to innumerable students, researchers, scientists, and engineers, and he will be sadly missed by all, who had the privilege to know him. He was an outstanding contributor in every aspect of his prolific work and career in the true traditions of technical excellence and critical thinking, and his irreplaceable loss is deeply felt worldwide.

Cointegration Modelling for Health and Condition Monitoring of Wind Turbines - An Overview

The cointegration method has recently attracted a growing interest from scientists and engineers as a promising tool for the development of wind turbine condition monitoring systems. This paper presents a short review of cointegration-based techniques developed for condition monitoring and fault detection of wind turbines. In all reported applications, cointegration residuals are used in control charts for condition monitoring and early failure detection. This is known as the residual-based control chart approach. Vibration signals and SCADA data are typically used with cointegration in these applications. This is due to the fact that vibration-based condition monitoring is one of the most common and effective techniques (used for wind turbines); and the use of SCADA data for condition monitoring and fault detection of wind turbines has become more and more popular in recent years.

How Half-Causation can enlighten the drafting of patent claims

The author’s 2019 article ‘If You Wish to Invent Then Follow the Half-Causation Method’ presented ‘Half-Causation’, which is a philosophical model for the systemization of the invention process. It consists of five phases of reasoning, each terminating with taking a ‘logical branch’. This paper has two objectives. The first (and preliminary) objective is to introduce a readership in patent practices (and theory) to Half-Causation. The second (and primary) objective is to highlight how Half-Causation can be practically useful to patent practitioners (and perhaps ultimately theorists), specifically in terms of enlightening the drafting of patent claims. In order to do this effectively, the reader is presented with a case which they can engage with to see for themselves how Half-Causation can help, step by step. The presented case was the subject of the USPTO’s 2019 patent drafting competition. It consists of rather convoluted instructions received from an ‘imaginary’ client about their ‘imaginary’ invention. The case is an excellent opportunity to illustrate how Half-Causation as a philosophical model can be practically useful. Two Half-Causation tools are implemented. The first is Half-Causation Branching, which allows the logical mapping of the inventing space, within which the imaginary invention is located. Implementing this tool reveals two alternative nearby inventions, which if left out of the sought patent protection would render any eventually granted patent practically worthless. Following that, Half-Causation Encapsulation comes to the rescue by allowing the encapsulation of the original imaginary invention, plus the two alternative nearby ones, all in a manner that provides the all-important unity of invention On the one hand, patent agents are not supposed to contribute to their client’s inventive concept to the extent that they become co-inventors. On the other hand, scientists and engineers are not supposed to dedicate so much time and effort to learning about complex patent laws as to become patent agents. Arguably, each should aim to excel in their discipline. However, a structured dialogue should be considerably helpful to each and to the patent process as a whole. It is proposed that Half-Causation, with its logical structure, can provide a basis for such a dialogue. Besides targeting a readership in patent practices and theory, this paper should be of interest to multiple readerships, for example in engineering design, medical discovery and philosophy of technology.

Computational Electromagnetics: A Miscellany

The paper presents a miscellany of unorthodox and, in some cases, paradoxical or controversial items related to computational and applied electromagnetics. The topics include a definition of the magnetic source field via a line integral, losses in electric power transmission vs. losses in photonics, homogenization of periodic electromagnetic structures, spurious modes, models of plasmonic media, and more. It is hoped that this assortment of subjects will be of interest to a broad audience of scientists and engineers.

The History and Practice of AI in the Environmental Sciences

Artificial intelligence (AI) and machine learning (ML) have become important tools for environmental scientists and engineers, both in research and in applications. Although these methods have become quite popular in recent years, they are not new. The use of AI methods began in the 1950s and environmental scientists were adopting them by the 1980s. Although an “AI Winter” temporarily slowed the growth, a more recent resurgence has brought it back with gusto. This paper tells the story of the evolution of AI in the field through the lens of the AMS Committee on Artificial Intelligence Applications to Environmental Science. The environmental sciences possess a host of problems amenable to advancement by intelligent techniques. We review a few of the early applications along with the ML methods of the time and how their progression has impacted these sciences. While AI methods have changed from expert systems in the eighties to neural networks and other data-driven methods, and more recently deep learning, the environmental problems tackled have remained similar. We discuss the types of applications that have shown some of the biggest advances due to AI usage and how they have evolved over the past decades, including topics in weather forecasting, probabilistic prediction, climate estimation, optimization problems, image processing, and improving forecasting models. We finish with a look at where AI as employed in environmental science appears to be headed and some thoughts on how it might be best blended with physical / dynamical modeling approaches to further advance our science.

Geochemical and Biogeochemical Reaction Modeling

An indispensable primer and reference textbook, the third edition of Geochemical and Biogeochemical Reaction Modeling carries the reader from the field's origins and theoretical underpinnings through to a collection of fully worked examples. A clear exposition of the underlying equations and calculation techniques is balanced by real-world example calculations. The book depicts geochemical reaction modeling as a vibrant field of study applicable to a wide spectrum of issues of scientific, practical, and societal concern. The new edition offers a thorough description of surface complexation modeling, including two- and three-layer methods; broader treatment of kinetic rate laws; the effect of stagnant zones on transport; and techniques for determining gas partial pressures. This handbook demystifies and makes broadly accessible an elegant technique for portraying chemical processes in the geosphere. It will again prove to be invaluable for geochemists, environmental scientists and engineers, aqueous and surface chemists, microbiologists, university teachers, and government regulators.

PHYSICO-TRIBOLOGICAL ANND WEAR MECHANISM CHARACTERISTICS OF HYBRID REINFFORCED Al6063 MATRIX COMPOSITES

The development of engineering materials is continuously attracting attention from scientists and engineers for numerous engineering applications. The physical properties and wear mechanism of aluminium (Al 6063) matrix reinforced with silicon carbide (SiC) and palm kernel shell ash (PKSA) particulates at different weight ratios ranging from 0 to 10 wt.% with 2 wt.% intervals were investigated. The liquid route of double stir casting was employed in synthesizing the composites. The wear experiment was conducted using the Taber-type wear abrasion machine. The worn surfaces were examined using scanning electron microscopy (SEM) with energy-dispersive x-ray spectroscopy (EDS), while the intermetallic phases were examined using the x-ray diffractometer (XRD). From the result, the increase in PKSA and SiC lowered and improved the density of the composites, respectively. The percentage porosity values (2 - 2.4%) obtained in this study were found to be within the acceptable limit of less than 4% for metal matrix composites castings. The mass loss and wear index increased owing to the rotating speed and applied load increase, resulting from the occurrence of mechanical mixing between the contacting surface of the sample disk and the machined disc. Adhesive and abrasive wear mechanisms were the major mechanisms observed in this study.

Fifty years of Rietveld refinement: Methodology and guidelines in superconductors and functional magnetic nanoadsorbents

The Rietveld refinement method has taken high relevance since its creation. Nowadays, it is an useful tool in many fields of industry, materials science, and technology. For these reasons, it becomes a need for scientists and engineers whom pretend to use it for proper analysis of their materials. However, the initiation in the method can be slow, taking into account the accelerated rhythm of the research and economic demands. Thus, this work is an intend to fulfill this hole, providing the basic foundations and methodology of the Rietveld refinement in a brief way, this along with the results of its application in superconducting samples of Yttrium Barium Copper Oxide and magnesium diboride, and functional magnetic nanoadsorbents of maghemite and a multiphasic composite (iron oxide, hydroxyapatite and secondary phases). In the process, an in-detail protocol was designed and provided. It was concluded that the samples were successfully refined and that this work represents a fast introduction to the Rietveld method for which beginners can obtain good results while making correct interpretations ofthe whole refinement process.