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The purpose of this paper is to develop a method for multiple soft fault diagnosis of nonlinear circuits including fault detection, identification of faulty elements and estimation of their values in real circumstances.

The method for fault diagnosis proposed here uses a measurement test leading to a system of nonlinear equations expressing the measured quantities in terms of the circuit parameters. Nonlinear functions, which appear in these equations are not given in explicit analytical form. The equations are solved using a homotopy concept. A key problem of the solvability of the equations is considered locally while tracing the solution path. Actual faults are selected on the basis of the observation that the probability of faults in fewer number of elements is greater than in a larger number of elements.

The results indicate that the method is an effective tool for testing nonlinear circuits including bipolar junction transistors and junction field effect transistors.

The homotopy method is generalized and associated with a restart procedure and a numerical algorithm for solving differential equations. Testable sets of elements are found using the singular value decomposition. The procedure for selecting faulty elements, based on the minimal fault number rule, is developed. The method comprises both theoretical and practical aspects of fault diagnosis.

The purpose of this paper is to develop a method for finding all the DC solutions in nonlinear circuits with the thermal constraint.

The proposed approach employs an algorithm for finding all the DC solutions without thermal constraint, including a new contraction and elimination method, an efficient method for tracing characteristics expressing voltages and power in terms of temperature, and electrical analog of the chip thermal behavior.

The paper brings a method that guarantees finding all the DC solutions, considering thermal behavior of the chip, in mid‐scale practical transistor circuits.

A new contraction and elimination method, being the core of the algorithm for finding all the DC solutions, is proposed. An approach enabling us to consider a feedback between the power dissipated inside the chip and the temperature, which affects the circuit parameters and consequently the solutions is developed.

Showing both theoretically and experimentally that the Newton‐Raphson algorithm is a very efficient tool for computing the transfer factor characteristic of AM detectors.

An equation which describes the diode and transistor AM detectors has been investigated. Using elementary techniques of mathematical analysis, some theoretical properties of the equation have been formulated and convergence of the Newton‐Raphson algorithm has been proved.

It is shown that the Newton‐Raphson algorithm is an efficient tool for tracing the transfer factor characteristics of both diode and transistor AM detector. The convergence of this algorithm is proved and a comparison with SPICE simulation is made. Furthermore, the diode and transistor AM detectors have been built up and validating measurements have been carried out. The comparison shows that the algorithm proposed in the paper computes the characteristics fast achieving good accuracy.

The results obtained are limited to those described in the paper diode and transistor AM detectors.

Some properties of the nonlinear equation describing the AM detectors are formulated and convergence of the Newton‐Raphson algorithm to a unique solution is proved.

The practical need for understanding and improving team resilience has increased, and more research is needed to provide an evidence-base for guiding organizational practices and policies. In this chapter, the authors highlight what we see as critical challenges and opportunities for advancing the science of team resilience. We focus on conceptual and methodological challenges involved in conducting field-based research on team resilience, as the authors believe field-based research is a particularly critical approach for advancing the science of team resilience. The authors first provide a brief review of recent theoretical work in defining team resilience. Then the authors describe key challenges that must be managed in field studies seeking to refine and capitalize on this critical area of research to provide solutions capable of supporting individual, team, and organizational outcomes. These challenges include defining trajectories of resilient team performance, understanding the consequences of repeated episodes of team resilience, formal specifications of events precipitating resilient team performance, measuring the event appraisal and communication process, and adopting measurement methods with high temporal resolution. Finally, the authors provide directions for future research to address these gaps.

Developing an efficient second‐order integration method of transient analysis of nonlinear dynamic circuits which overcomes the main drawback of the trapezoidal rule.

Dynamic circuits including transistors and operational amplifiers are considered. A new family of two‐step, second‐order numerical integration algorithms has been developed using a polynomial approximation.

The algorithms have been worked out which are implicit, A‐stable and they depend on a parameter which is allowed to be changed during the computation process according to a proposed strategy. Also the variable step‐size formula has been derived enabling us to eliminate a restarting procedure. The method has been implemented and tested using several representative circuits. It has been compared, both theoretically and via numerical examples, with the alternative well known algorithms: the trapezoidal rule and the backward differentiation formula of order two.

The algorithms developed in the paper are two‐step and second‐order, consequently the step size cannot be too large and the algorithms are not L‐stable.

A new family of two‐step implicit integration algorithms is developed. It can be useful for the analysis and design of electronic circuits.

Passive conducting elements are the important parts of textronic systems. This paper aims to study a possibility of creating well-conducting and durable elements in textile materials by combining two technologies – physical vapour deposition (PVD) and laser patterning.

Thin conducting metallic layers on common fabrics do not provide satisfactory resistance to bending and stretching; therefore, selected textile composite materials have been proposed as a substrate. The conducting elements were produced in two stage process – deposition of thin metallic layer on textile composite and creating conducting elements by laser patterning. Laser ablation process was optimized using modelling in Comsol Multiphysics package. Properties of conducting structures were investigated experimentally and by modelling.

This paper confirms the correctness of the choice of the textile composite as a substrate for conducting elements. The results have shown that combining PVD deposition of thin metallic layer and controlled laser ablation allow creating passive elements such as resistors, inductive coils and heaters. Computer simulations conducted in the Comsol Multihysics environment enabled to determine the temperature distribution around the heaters and to describe the dynamics of its changes. The obtained results allow to shorten time of the optimization process of structures with different geometry and assumed temperature distribution.

The novelty of this research can be summarized as following: choosing of textile composites as substrates for conductive elements instead of textiles used so far in textronics; creating conductive structures on textile composites using combined technologies, PVD and laser patterning, for the first time; modelling of laser ablation process of thin metallic layer; and optimization of properties of conducting elements by computer modelling.

Firefighter Personal Protective Equipment (PPE) is the only barrier between the firefighter and hazardous environment. Gloves are a crucial component of the multi-component PPE. Over time the gloves have reduced the intensity of hand injuries, yet further improvement in terms of material selection and glove design is required to strike the balance between protection and comfort. Focusing on the material aspect, the purpose of this study is to present literature analysis on material selection and testing for firefighter gloves.

The study conducted a literature analysis on material selection and characterization of firefighter PPE. The review summarizes and evaluates past work addressing the characterization of firefighter gloves in accordance with NFPA 1971 requirements and points out found research gaps to aid with foundation of future research.

The study summarizes several research works to inform readers about the material selection and characterization of firefighter gloves. Based on the analyzed literature, the study resulted in material specification sheets for firefighter gloves. The developed material specification sheets provide information in terms of crucial material properties to be incorporated for accurate functioning of firefighter gloves, testing methods to validate those material properties and materials from analyzed literature exhibiting desired properties.

With large research addressing firefighter PPE, only limited studies focus specifically on gloves. Thus, this study provides a literature analysis covering material selection and testing for gloves. A consolidated firefighter gloves material specification document, which does not appear to be available in the literature, will provide a foundation for the development and characterization of firefighter gloves to better serve the functions along with ensuring user comfort.