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In the recent work, a new blast-wave impact-mitigation concept involving the use of a protective structure consisting of bimolecular reactants (polyvinyl pyridine+cyclohexyl chloride), capable of undergoing a chemical reaction (to form polyvinyl pyridinium ionic salt) under shockwave loading conditions, was investigated using all-atom reactive equilibrium and non-equilibrium molecular-dynamics analyses. The purpose of this paper is to reveal the beneficial shockwave dispersion/attenuation effects offered by the chemical reaction, direct simulations of a fully supported single planar shockwave propagating through the reactive mixture were carried out, and the structure of the shock front examined as a function of the extent of the chemical reaction (i.e. as a function of the strength of the incident shockwave). The results obtained clearly revealed that chemical reactions give rise to considerable broadening of the shockwave front. In the present work, the effect of chemical reactions and the structure of the shockwaves are investigated at the continuum level.

Specifically, the problem of the (conserved) linear-momentum accompanying the interaction of an incident shockwave with the protective-structure/protected-structure material interface has been investigated, within the steady-wave/structured-shock computational framework, in order to demonstrate and quantify an increase in the time period over which the momentum is transferred and a reduction in the peak loading experienced by the protected structure, both brought about by the occurrence of the chemical reaction (within the protective structure).

The results obtained clearly revealed the beneficial shock-mitigation effects offered by a protective structure capable of undergoing a chemical reaction under shock-loading conditions.

To the authors’ knowledge, the present manuscript is the first report dealing with a continuum-level analysis of the blast-mitigation potential of chemical reactions.

The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors affecting the TPP using model visualization.

A total of 13 machine learning models were trained by collecting 414 datasets of typical flame-retardant fabric from current literature. The optimal performance model was used for feature importance ranking and correlation variable analysis through model visualization.

Five models with better performance were screened, all of which showed R2 greater than 0.96 and root mean squared error less than 3.0. Heat map results revealed that the TPP of fabrics differed significantly under different types of thermal exposure. The effect of fabric weight was more apparent in the flame or low thermal radiation environment. The increase in fabric weight, fabric thickness, air gap width and relative humidity of the air gap improved the TPP of the fabric.

The findings suggested that the visual analysis method of machine learning can intuitively understand the change trend and range of second-degree burn time under the influence of multiple variables. The established models can be used to predict the TPP of fabrics, providing a reference for researchers to carry out relevant research.

The findings of this study contribute directional insights for optimizing the structure of thermal protective clothing, and introduce innovative perspectives and methodologies for advancing heat transfer modeling in thermal protective clothing.

The purpose of this paper is to present a finite element simulation to validate the strength and energy absorption capacity of a rollover protective structure (ROPS) of agricultural tractors. The test consists of four steps: rear loading, crushing of the rear columns, side loading and crushing of the front columns. In this study a new design of a cabin for narrow tractors was simulated and from it the computational test was run for validation of the cabin. The simulation was performed using ANSYS software, considering the nonlinear characteristics of the materials, since during the test the plastic limit is reached. With the computational results, it was possible to predict the behavior of the structure before the real test. These results were used to propose design and materials changes that significantly improved the energy absorption, making it more efficient. The proposed cabin design reaches the energies and forces required in each step of the computational simulation of the ROPS test and the deformation needed to achieve them does not cause any cabin part to enter the operator survival space inside the cabin.

In the present study, numerous finite elements simulations have been carried out on a narrow cab for tractors.

It was conclude that it is possible to virtually test the ROPS, making material and design changes in order to have a more adequate structure before a first real test.

The present study is part of Tiago R. Cesa's Master thesis, an original research work.

Purpose – In this chapter, I set out to unexcise the messiness of maternalisms and disparities in women's health care by addressing narratives about reproductive trauma. I ask, what might it mean to analyze the interaction between the medical industrial complex and women who experience reproductive trauma as a social practice, one that is constitutive of gender socialization and the medicalization of women's bodies in the American nation-state? I accomplish responding to the question by addressing a vastly underresearched and underaddressed pregnancy complication Hyperemesis Gravidarum (HG).

Methodology/Approach – First, I thread posts from supportive online reproductive trauma forums to weave thematic narratives about and the impacts of HG. Next, I review biomedical literature in order to probe potential etiology. Third, I share my debilitating experiences with HG – reproductive traumas – to interrogate dominant androcentric biomedical discourse of pregnancy culture, maternalisms, maternal ideology, and epistemic violence.

Findings – Our knowledge about HG continues to be murky and unresolved, leaving many pregnant people – namely women – untreated.

Research limitations/implications – I call on the absence of contemporary protective sociocultural structures that provide support and care – gendered health-care disparities – for women during pregnancy, labor and delivery, and postpartum in order to advocate reproductive trauma is a viable and normal expression in the context of misogynist social scripts.

Originality/Value of the Chapter – My hope is to raise the volume on narratives of pregnancy trauma and reproductive experience using HG as a case study and my intention is to argue gender is a salient factor in health-care disparities.

Offenders with intellectual disability (ID) have been largely neglected in past forensic literature on assessment of dynamic risk factors. The purpose of this paper is to evaluate the predictive validity of the Short-Term Assessment of Risk and Treatability (START), in a sample of males with IDs in a low-secure hospital (n=28).

A prospective analysis was conducted, with START scores as the predictor variables, and the number of recorded aversive incidents as the outcome measure.

Receiver operating characteristic analysis demonstrated that total START risk scores had a significant high predictive accuracy for incidents of physical aggression to others (area under the curve (AUC)=0.710, p<0.001) and property damage/theft (AUC=0.730, p<0.001), over a 30-day period, reducing to medium predictive validity over a 90-day period. Medium predictive validity was also identified for incidents of verbal aggression, suicide, self-harm, and stalking and intimidation. START strength scores were also predictive of overt aggression (AUC=0.716), possible reasons for this are explored.

The small sample size limits the generalisability of the findings, and further research is required.

The paper offers preliminary support for the use of the START with ID offenders in low-secure settings. Given the lack of validation of any previous dynamic risk assessment tools, multi-disciplinary teams in such settings now have the option to use a tool which has potentially good validity with an ID population.

This study represents the first attempt to examine the predictive validity of the START with ID offenders, and a step forward in the understanding of dynamic risk factors for violence in this population. The significant predictive relationship with incidents of physical aggression and property damage offers clinicians a preliminary evidence base supporting its use in low-secure settings.

The purpose of this paper is to investigate relationships of urban seismic resilience assessment indicators.

To achieve this aim, construction of the urban seismic resilience assessment indicators system was conducted and 20 indicators covering five dimensions, namely building and lifeline infrastructure, environment, society, economy and institution were identified. Following this, this study used evidence fusion theory and intuitionistic fuzzy sets to process the information from experts then developed the fuzzy total interpretive structure model.

A total of 20 urban seismic resilience assessment indicators are reconstructed into a hierarchical and visual system structure including five levels. Indicators in the bottom level including debris flow risk, landslide risk, earthquake experience and demographic characteristics are fundamental indicators that significantly impact other indicators. Indicators in the top level including open space, gas system and public security are direct indicators influenced more by other indicators. Other indicators are in middle levels. Results of MICMAC analysis visually categorize these indicators into independent indicators, linkage indicators, autonomous indicators and dependent indicators according to driving power and dependence.

This paper attempts to explore relationships of urban seismic resilience assessment indicators with the interpretive structural model method. Additionally, Fuzzy total interpretive structure model is developed combined with evidence fusion theory and intuitionistic fuzzy sets, which is the extension of total interpretive structure model. Research results can assist the analytic network process method in assessing urban seismic resilience in future research.

The purpose of this paper is to introduce and analyze a new blast-wave impact-mitigation concept using advanced computational methods and tools. The concept involves the use of a protective structure consisting of bimolecular reactants displaying a number of critical characteristics, including: a high level of thermodynamic stability under ambient conditions (to ensure a long shelf-life of the protective structure); the capability to undergo fast/large-yield chemical reactions under blast-impact induced shock-loading conditions; large negative activation and reaction volumes to provide effective attenuation of the pressure-dominated shockwave stress field through the volumetric-energy storing effects; and a large activation energy for efficient energy dissipation. The case of a particular bimolecular chemical reaction involving polyvinyl pyridine and cyclohexyl chloride as reactants and polyvinyl pyridinium ionic salt as the reaction product is analyzed.

Direct simulations of single planar shockwave propagations through the reactive mixture are carried out, and the structure of the shock front examined, as a function of the occurrence of the chemical reaction. To properly capture the shockwave-induced initiation of the chemical reactions during an impact event, all the calculations carried out in the present work involved the use of all-atom molecular-level equilibrium and non-equilibrium reactive molecular-dynamics simulations. In other words, atomic bonding is not pre-assigned, but is rather determined dynamically and adaptively using the concepts of the bond order and atomic valence.

The results obtained clearly reveal that when the chemical reactions are allowed to take place at the shock front and in the shockwave, the resulting shock front undergoes a considerable level of dispersion. Consequently, the (conserved) linear momentum is transferred (during the interaction of the protective-structure borne shockwaves with the protected structure) to the protected structure over a longer time period, while the peak loading experienced by the protected structure is substantially reduced.

To the authors’ knowledge, the present work is the first attempt to simulate shock-induced chemical reactions at the molecular level, for purposes of blast-mitigation.

Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The aim of this paper is to determine the thermal conductivity of a protective layer of alkali-activated cement and the possibility of performing fire protection with fireclay sand and Lightweight mortar. Unprotected steel structures have generally low fire resistance and require surface protection. The design of passive protection of a steel element must consider the service life of the structure and the possible need to replace the fire protection layer. Currently, conventional passive protection options include intumescent coatings, which are subject to frequent inspection and renewal, gypsum and cement-based fire coatings and gypsum and cement board fire protection.

Alkali-activated cements provide an alternative to traditional Portland clinker-based materials for specific areas. This paper presents the properties of hybrid cement, its manufacturability for conventional mortars and the development of passive fire protection. Fire experiments were conducted with mortar with alkali-activated and fireclay sand and lightweight mortar with alkali-activated cement and expanded perlite. Fire experiment FE modelling.

The temperatures of the protected steel and the formation of cracks in the protective layer were investigated. Based on the experiments, the thermal conductivities of the two protective layers were determined. Conclusions are presented on the applicability of alkaline-activated cement mortars and the possibilities of applicability for the protection of steel structures. The functionality of the passive fire layer was confirmed and the strengths of the mortar used were determined. The use of alkali-activated cements was shown to be a suitable option for sustainable passive fire protection of steel structures.

Eco-friendly fire protection based on hybrid alkali-activated cement of steel members.

In the present work, a new blast-/ballistic-impact mitigation concept is introduced and its efficacy analyzed using advanced computational methods and tools. The concept involves the use of a zeolite protective layer separated by air from the structure being protected and in contact with a water layer in front. The paper aims to discuss these issues.

To properly capture the attendant nano-fluidics phenomena, all the calculations carried out in the present work involved the use of all-atom molecular-level equilibrium and non-equilibrium molecular-dynamics simulations.

Under high-rate loading, water molecules (treated as a nano-fluidic material) are forced to infiltrate zeolite nanopores wherein, due to complex interactions between the hydrophobic nanopore walls and the hydrogen bonds of the water molecules, water undergoes an ordering-type phase transition and acquires high density, while a significant portion of the kinetic energy of the water molecules is converted to potential energy. Concomitantly, a considerable portion of this kinetic energy is dissipated in the form of heat. As a result of these energy conversion/dissipation processes, the (conserved) linear momentum is transferred to the target structure over a longer time period, while the peak loading experienced by the structure is substantially reduced.

To the authors’ knowledge, the present work constitutes the first reported attempt to utilize pure SiO₂ hydrophobic zeolites in blast-/ballistic-impact protection applications.