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This paper aims to estimate the performance of protective clothing used to resist puncture (anti-stab property).

Seven single-layer (one layer) samples were investigated in this research. The first three samples were already used for the purpose of (anti-stab property), manufactured from Du-Pont product (commercial samples). The rest of the samples were locally designed and manufactured for the same purpose. These seven samples have then been examined after been added in conjunction with WL Kevlar XP (S 104) witness multilayers (eight layers) panel to create which are called multilayer samples.

The results of the statistical analysis for one-way ANOVA illustrated significant effect for single layer samples for all properties. While for multi-layer samples, the results showed a significant difference for all variables except displacement. The Tukey post hoc test observed a significant effect for some samples; also, other samples show a non-significant effect between samples.

It was observed that the locally manufactured samples serve the purpose as (anti-stab samples) compared with the commercial samples. The radar chart shows that for single-layer sample, the fifth sample fulfill the highest radar chart area, whereas for multi-layer samples, the sixth sample achieved the highest radar chart area.

This paper aims to investigate the performance of four different textile materials used as an outer shell of the bulletproof vest.

In this paper, four different textile materials were used, polyurethane treatment was applied as a surface coating for the woven samples. Mechanical properties were conducted for all samples; scanning electron microscope and X-ray energy disperse spectroscopy were executed to show the surface morphology of samples and the chemical composition of the coating material.

One-way ANOVA was used to statistically analyse the results, which proved that all variables were highly significantly affected by using different textile materials, despite the stiffness variable being not significantly affected by textile materials. An overall evaluation was done using radar chart, demonstrated that Cordura material accomplished the best functional performance, using two types of calibres 7.62 × 54 mild steel core and 7.62 × 54 armour piercing incendiary; the common mechanism was localized burn because of the incendiary effect of the projectile in addition to tearing mechanism starting from inside because of penetration effect of the steel core.

This work was addressed to analyse the impact of using four different materials on its performance as the outer shell of bulletproof vest to achieve the desired degree of protection.

The purpose of this work is to perform an application study on experimental animals (dogs) to investigate the efficiency of using weft knitted mesh fabric as cardiac support mesh to support left ventricular hypertrophy.

In this work, weft-knitted mesh sample “Knitted Cardiac Support Mesh” manufactured using Nylon (6, 6) yarns, with count 20 Denier and medium mesh size, was placed around the two ventricles to prevent further dilatation, support and reduce left ventricular wall stress.

Medical textile is a rapidly expanding field in technical textiles that are widely used in a variety of medical applications. One of these medical textile applications is “Knitted Cardiac Support Mesh”, which is used in the treatment of Dilated Cardiomyopathy.

After the implantation of the manufactured Knitted Cardiac Support Mesh around the myocardium, all dogs survived for three months before being euthanized, and some clinical examinations were performed to investigate and evaluate the sample performance. It was demonstrated from the experimental application, that the nylon mesh sample performed the best during the surgical operation due to its good ability to stretch and recover at a moderate rate, as well as the textile mesh lightweight.

This paper aims to present the classification, representation and extraction of adhesively bonded assembly features (ABAFs) from the computer-aided design (CAD) model.

The ABAFs are represented as a set of faces with a characteristic arrangement among the faces among parts in proximity suitable for adhesive bonding. The characteristics combination of the faying surfaces and their topological relationships help in classification of ABAFs. The ABAFs are classified into elementary and compound types based on the number of assembly features exist at the joint location.

A set of algorithms is developed to extract and identify the ABAFs from CAD model. Typical automotive and aerospace CAD assembly models have been used to illustrate and validate the proposed approach.

New classification and extraction methods for ABAFs are proposed, which are useful for variant design.

Critical theory has rarely articulated an agenda for social change linking theory to practice. This paper provides several examples of “critical theory in practice” and focuses specifically on Fay’s Critical Social Science (CSS) model. The methods of conflict transformation are then applied to CSS in order to accomplish two goals. First, political conflicts resulting from decision making can be used to transform both individuals and systems. Second, CSS more adequately accounts for some of the non-rational aspects of human nature, such as our resistance to change, thus improving its catalytic validity as a critical social theory. Together, the processes of CSS and conflict transformation provide a framework for enhancing the potential for citizen governance.

The Fay and Riddell (F–R) formula is an empirical equation for estimating the stagnation-point heat flux on noncatalytic and fully catalytic surfaces, based on an assumption of equilibrium. Because of its simplicity, the F–R has been used extensively for reentry flight design as well as ground test facility applications. This study aims to investigate the uncertainties of the F-R formula by considering velocity gradient, chemical species at the boundary layer edge, and the thermochemical nonequilibrium (NEQ) behind the shock layer under various hypersonic NEQ flow environments.

The stagnation-point heat flux calculated with the F–R formula was evaluated by comparison with thermochemical NEQ calculations and existing flight experimental values.

The comparisons showed that the F–R underestimated the noncatalytic heat flux, because of the chemical composition at the surface. However, for fully catalytic heat flux, the F–R results were similar to values of surface heat flux from thermochemical NEQ calculations, because the F–R formula overestimates the diffusive heat flux. When compared with the surface heat flux results obtained from flight experimental data, the F–R overestimated the fully catalytic heat flux. The error was 50% at most.

The results provided guidelines for the F–R calculations under hypersonic flight conditions and for determining the approximate error range for noncatalytic and fully catalytic surfaces.

In responding to competitors' strategic choices, firms must choose whether to allocate their customer relationship management (CRM) resources primarily to retaining existing customers or to acquiring new customers. To address this critical but understudied question, the authors examine the strategic choices of two competing firms between retention- and acquisition-focused strategies in consideration of switching costs, technological advancement level, and market share.

The authors develop and analyze a game-theoretic model to investigate the strategic choices of two competing firms between retention- and acquisition-focused strategies.

When switching costs are high, findings show that when the degree of technological advancement is high (low), both firms should employ acquisition-focused (retention-focused) strategies to maximize their profits. When switching costs are low and there are a low degree of technological advancement and asymmetric market shares, the firms choose retention-focused strategies in equilibrium, but only the firm with the higher market share can maximize its profit. When switching costs are low, technological advancement levels are high, and the market shares are asymmetric, the firm with the higher market share chooses a retention-focused CRM strategy, while the rival with lower market share adopts an acquisition-focused strategy in equilibrium. However, neither firm can maximize its profits.

Prior research focused on a single firm's price discrimination decision without considering a competitor's strategic choice. To address this research gap, the authors examine where firms should assign their CRM resources (retention vs. acquisition) in response to a competitor's CRM strategy. This study provides guidance for optimal decision-making regarding a firm's CRM resource allocation in a duopoly market.

Purpose – This study explored agentive and sustainable teacher development as part of literacy coaching that employed a reflective framework and video with an apprenticeship stance. This chapter examines principles of apprenticeship and the Gradual Release of Responsibility (GRR) model to analyze the transition of responsibility for reflection from coach to teacher.

Design/methodology/approach – An earlier seven-month multiple case study of literacy coaching with four secondary level teachers revealed seven joint actions (i.e., revoice, build, ask questions to develop understanding, ask dissonant questions, suggest, disagree, reconceptualize) and four categories of joint action (i.e., directive/consonant, directive/dissonant, responsive/consonant, and responsive/dissonant) within a model of joint action for literacy coaching (Reichenberg, 2018). This analysis mapped those joint actions onto the GRR model (McVee, Shanahan, Hayden, Boyd, & Pearson, 2018; Pearson & Gallagher, 1983). This chapter explicates reasoning for variability in responsibility and the potential relationship between variability and the development of teachers’ thinking and action through in-depth analysis of a single coaching session. Examples from other teachers’ coaching sessions are included.

Findings – Synthesis of the two models shows that joint actions initiated by the coach that were directive/dissonant fell on the left side of the GRR model with primary coach responsibility. Actions initiated by the coach that were classified as directive/consonant came next on the journey toward the middle, followed by responsive/dissonant actions. Responsive/consonant actions encompassed the middle region of shared responsibility. The same actions initiated by the teacher mirrored this progression. Principles of apprenticeship in this gradual release of responsibility highlight the bi-directionality of expertise in situated action informed by historical and dynamic context (Mercer, 2008). Evidence of teachers’ growing agency and sustainability were present in joint actions they initiated within the context of literacy coaching.

Research limitations/implications – Analysis of the actions of a literacy coach and teacher as directive, responsive, consonant, and dissonant add complexity to the discussion about how to transfer responsibility for reflection from coaches to teachers. Awareness of how joint actions map onto the GRR model can inform coaches’ and teachers’ decisions as they thoughtfully move toward greater teacher agency within coaching interaction.

Practical implications – The reflective framework employed in this study is applicable to a variety of settings such as instructional coaching across the disciplines, coaching by in-service literacy specialists, and the preparation of pre-service literacy coaches. The model of joint action for analyzing coaching interaction could be used by in-service literacy coaches, pre-service literacy coaches, and teachers who are being coached.

Originality/value – This chapter analyzes the transition of responsibility for reflection from coach to teacher. Principles of both the GRR model and apprenticeship theory provide a theoretical explanation for how these teachers achieved greater agency and sustainable development of a reflective stance.