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Recent USA police responses to civil rights demonstrations have drawn attention toward the 1033 Program – a military surplus transfer program from the Department of Defense (DOD) to police agencies in the USA – as well as calls for dissolution or reform of the program. However, policy decisions have been sporadic and empirical literature examining the program have relied on public data, which contain information about equipment transfers, but does not show the frequency of agencies' use of this equipment – or contexts of use – once received.

This study presents the findings of a survey of a national sample of law enforcement agencies that used the program to obtain armored vehicles, rifles, and body armor and how these agencies used this equipment in 2019 and 2020. Correlations and binary logistic regression models are tested for 2019 to examine the racial threat hypothesis and additional predictors of equipment use.

A statistically significant correlation is found between perceived percentage of Black and other race residents and the frequency of armored vehicle deployment in 2019 and between the perceived percentage of other race residents and the percentage of special weapons and tactics (SWAT) officers wearing body armor. Perceived increases in drug crimes also significantly increase the likelihood of SWAT officers carrying military rifles, with increased odds of 402.3%.

This study is the first to examine contextual data surrounding law enforcement use of 1033 Program acquisitions with a national sample, assisting in providing greater accuracy in determining predictors and outcomes of the program's use.

In order to help explain experimental findings related to the stabbing- and ballistic-penetration resistance of flexible body-armor, single-yarn pull-out tests, involving specially prepared fabric-type test coupons, are often carried out. The purpose of this paper is to develop a finite-element-based computational framework for the simulation of the single-yarn pull-out test, and applied to the case of Kevlar® KM2 fabric.

Three conditions of the fabric are considered: neat, i.e, as-woven; polyethylene glycol (PEG)-infiltrated; and shear-thickening fluid (STF)-infiltrated. Due to differences in the three conditions of the fabric, the computational framework had to utilize three different finite-element formulations: standard Lagrangian formulation for the neat fabric; combined Eulerian-Lagrangian formulation for the PEG-infiltrated fabric (an Eulerian subdomain had to be used to treat the PEG solvent/dispersant); and combined continuum Lagrangian/discrete-particle formulation for the STF-infiltrated fabric (to account for the interactions of the particles suspended in PEG, which give rise to the STF character of the suspension, with the yarns, the particles had to be treated explicitly).

The results obtained for the single-yarn pull-out virtual tests are compared with the authors’ experimental counterparts, and a reasonably good agreement is obtained, for all three conditions of the fabric.

To the authors’ knowledge, the present work represents the first attempt to simulate single-yarn pull-out tests of Kevlar® KM2 fabric.

Examines the fifthteenth 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 purpose of this paper is to investigate the incremental impact of firefighter’s personal protective equipment (PPE) on lower body range of motion (ROM) while walking to suggest areas of design improvement for enhanced mobility and safety.

Eight male and four female firefighters participated in the study. Lower body ROM was assessed while they walked in four different configurations of PPE, including turnout ensemble, a self-contained breathing apparatus (SCBA) and boots. The impact of each added PPE item, and gender differences were statistically analyzed.

Wearing firefighter turnout ensemble and SCBA reduced ROM in the lower body in the sagittal and transverse planes. A significant reduction in ROM for anterior-posterior movement at the ankle and the ball of the foot was found while wearing rubber boots with turnout ensemble and SCBA. This puts firefighters at higher risk of experiencing foot injuries and physical strains. A significant increase in medial-lateral movement of the foot while wearing rubber boots may increase risk of ankle sprains. A greater reduction in ROM at the ankle and the ball of the foot for female firefighters may imply greater risk for women compared to men, while wearing boots.

Reducing the inflexibility and bulkiness of boots is critical to improve firefighter’s lower body mobility and safety.

This study implemented 3-D motion capture technology to analyze how wearing firefighting gear impacted lower body motion. It provides quantitative evidence to recommend ergonomic boot re-design.

Examines the fourteenth 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 main challenge in preparing body armor is achieving a high protection level by using lightweight materials with minimum cost.

In this study, a three-hybrid multilayered armor system is prepared for protection against a ballistic impact wave. These armor systems consist of glass or ceramic tile as a front layer followed by three intermediate layers made of woven fiber reinforced polymer composites and a back layer made of either aluminum or polypropylene.

All armor systems were successful in impeding the projectile from perforating, that is materials selection played an important role in stopping the ballistic impact wave. Almost an identical ballistic behavior was recorded between the experimental and numerical simulation by using ANSYS AUTODYN which means that the simulation could be used in advance to reduce the time required for practical experiments and the cost of using materials in experimental tests will be lessened. The effect of projectile geometry also had been studied, and it showed a noticeable role in changing ballistic behavior.

The originality of this research is in using carbon and glass fiber which are woven together in addition to adding polypropylene layers in armor preparation.

Stab-resistant body armor (SRBA) can protect the human body from injury as a result of stabbing by sharp projectiles. However, in its current design SRBA, it has not been widely adopted for use, because of its weight and poor flexibility. Herein, this paper aims to detail a new type of SRBA that is inspired by the armor plating of mammals and is fabricated using laser sintering (LS) technology.

This new type of SRBA was fabricated using LS technology. The laser sintered SRBA was subjected to a stab resistance performance test that conformed to the GA 68-2008 Chinese National Standard. The stab resistance response of the novel structured, stab resistance test plates in this study was analyzed using the using the AUTODYN explicit module in ANSYS-Workbench.

The structure of the novel stab resistance plate was designed and the optimum structural parameters were tested, discussed and achieved. The mechanism of dissipation of the impact energy by the pyramidal structures of the novel SRBA was studied, and it was found that this structure dispersed the kinetic energy of the knife and minimized the structural damage to the plate. Interlinks inspired by the pangolin hierarchy structure were designed and used to fabricate a large piece of laser sintered body armor.

High-performance laser sintered stab resistance plate was produced via the material and structure studies, which could reduce 40 per cent weight on the stab resistance body armor and increase the wearability.

The purpose of this paper is to establish the minimum thickness required to provide stab protection in accordance with the United Kingdom Home Office Scientific Development Branch (HOSDB) standards while testing a series of laser sintered (LS) planar specimens using instrumented test apparatus.

Planar test specimens were LS in single-layer thicknesses ranging from 1.00 to 15.00 mm in four material powder categories – DuraForm® virgin, DuraForm 50/50 mix, DuraForm EX® virgin and DuraForm EX 50/50 mix. All specimens were tested using instrumented drop test apparatus and were impacted with established Stanley Tools 1992 trimming blades to the UK HOSDB KR1-E1 stab impact energy level.

The research demonstrated that a minimum single planar specimen thickness of 11.00 mm, manufactured from DuraForm EX 50/50 mix powder, was required to provide protection against the HOSDB KR1-E1 level of stab impact energy. The alternative powder mixes tested within this experiment demonstrated poor levels of stab protection, with virgin powder specimens demonstrating no protection up to 15.00 mm, whereas DuraForm 50/50 mix specimens demonstrating inconsistent performances.

This paper enhances on existing literature surrounding the manufacturing and testing of additive manufacturing (AM) stab-resistant armour by adding further rigour to the testing of AM body armour specimens. In addition, this research establishes key foundation characteristics which could be utilised for the future development of bespoke AM body armour garments.

This study presents the design, manufacture and evaluation of a type of 3D hollow woven structure, as a mean for improving ventilation underneath ballistic body armour and thus, thermal comfort.

By means of a computational fluid dynamic package, fluid flows through different cross‐sectional tubular geometries were simulated in order to predict, which structural parameters of the 3D hollow fabrics are optimal to support ventilation.

As the result of the computational analysis four optimised 3D hollow woven structures were selected and generated on a standard weaving loom.

Investigation of thermal comfort of 3D ballistic vests.