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Fused deposition modeling enables multiscale structure control. However, most of this structural space is unexplored. Specifically, the impact of biomimetic porous structures on the mechanical behavior and reliability of common thermoplastics are unclear. In this work, porous structures inspired by the multifunctional crab exoskeleton were 3D-printed with different raster orientations, including fully rotating rasters similar to Bouligand structures found in biological materials. Tensile tests and simulations were performed to observe the stochastic behavior of fracture properties and to reveal the underlying origins of mechanical reliability in biomimetic porous systems.

Tensile tests were performed on 3D-printed porous structures with four different rasters. These rasters were biomimetic Bouligand, semi-Bouligand, 00 raster and 45°/−45° raster. In addition, two different sets were manufactured to observe the impact of contours on the mechanical behavior. A total of 137 tensile tests were performed. A total of 88 finite element simulations were executed using Abaqus built-in Hashin damage initiation criterion and energy-based damage evolution law. Weibull analyses were performed to quantify the stochastic properties.

Biomimetic Bouligand structure is effective in increasing fracture strength. Average fracture strength of the Bouligand structure was 33% higher compared to the default 45°/−45° and 10% higher compared to 00 rasters. Variations in strength were lower in Bouligand structure compared to the default 45°/−45° raster. However, 00 raster had the highest Weibull modulus m = 54 compared to Bouligand m = 25 and 45°/−45° m = 17. Simulations showed that Bouligand structure is effective in increasing the mechanical reliability through local damage accumulation around the holes. The simulated Weibull modulus of the Bouligand structure was 40 compared to the moduli of other rasters that ranged from 18 to 25.

The mechanical reliability of porous Bouligand structures is higher compared to other rasters, which makes the biomimetic structure a better choice for industrial applications. Contours decrease the strength and strain at failure for 3D-printed porous structures. Bouligand structures with rotating raster orientations increased strength and strain at failure when contours are present in the porous structure.

To the best of the authors’ knowledge, this is the first study showing the effects of biomimetic raster orientations on the mechanical behavior and the effects of contours on the tensile fracture properties of 3D-printed porous acrylonitrile butadiene styrene using tensile tests and fracture simulations. This is the first study applying composite fracture model to anisotropic porous 3D-printed polymers.

Mechanical reliability (variations in mechanical properties) of fused deposition modeled (FDMed) short-fiber-reinforced composites are unknown, which limits wider and safer use of these composites. Accordingly, this paper aims to investigate the mechanical reliability of FDMed model material short-carbon-fiber-reinforced acrylonitrile butadiene styrene (SCFR-ABS). A new vibration-assisted FDM (VA-FDM) process was used to reduce porosity.

Tensile tests were performed on FDMed SCFR-ABS produced with and without vibrations. Weibull analysis was performed to quantify the variation in fracture strength, tensile strength, strain at break and strain at tensile strength.

Introduction of vibrations to the extrusion head during FDM decreased the inter-bead porosity in SCFR-ABS and thus improved elastic modulus, toughness, fracture strength, tensile strength and strain at break. Weibull modulus of fracture strength increased from 25 to 57 with vibrations.

The reported Weibull analysis offers a practical design guideline to predict failure rates at specific service stresses.

A detailed Weibull analysis of the variations in the mechanical properties of FDMed SCFR-ABS was performed for the first time. A new vibration-assisted FDM process was reported to reduce inter-bead porosity in FDMed composites.

This issue is a selected bibliography covering the subject of leadership.

The aim of this chapter is to explore the relationship between contemporary sport, social media, digital technology, and sexuality and to explore the historical context of sport and sexuality, before then outlining the decline of homophobia in recent years. Despite this decline, social media is one area where we still see the manifestation of homophobia.

This chapter synthesizes a range of academic literature to chart how – despite improving attitudes toward homosexuality in sport – abuse and discrimination is still prevalent on social media.

Eric Anderson's (2009) Inclusive Masculinity Theory has been the most useful theoretical apparatus to underpin the changing nature of sport, gender, and sexuality. While this has been used in a variety of sporting contexts, these are primarily focused on gay male athletes in the West. Accordingly, there is a gap in knowledge around the experiences of lesbian, bisexual, and trans athletes, as well as those outside of the Western context.

Although there has been some literature to document discrimination on social media, very little focuses specifically on the manifestation of homophobia. Accordingly, this chapter provides an important contribution by being one of the first to tie together the literature on improved cultural attitudes toward homosexuality while simultaneously focusing on the prevalence of discrimination on social media.

The purpose of this paper is to address the recent calls for an in-depth investigation of the entrepreneurial marketing (EM) practices of small businesses and a further conceptual development of EM under market uncertainty. Drawing on the EM mix (i.e. person, purpose, practices and process), the authors aim to conceptualise EM under market uncertainty through principles of effectual networking.

The authors conducted an in-depth case study of an owner-manager who networks with many different stakeholders to create new markets for wool in the Norwegian wool industry.

Situated within the creative and craft-based industries, the study demonstrates that market uncertainty can be reduced through effectual networking to produce highly beneficial outcomes for small businesses. The findings give rise to a new model of the EM mix under uncertainty, emphasising the role of the owner-manager (i.e. person) and the purpose as the outset and driving force of the EM process. These two elements constitute the initial means in the means-driven EM process and the foundation for subsequent EM practices. The person, purpose and practices interact iteratively, and focal effectual networking principles guide EM practices.

This paper expands and contextualises existing theories on EM under market uncertainty by introducing the effectual networking perspective. This represents a hitherto under-investigated area of research in small business marketing.

When James Conant visited Australia in 1951 he unwittingly entered an existing, lengthy debate about the value of university‐based knowledge in Australia. The Second World War, with its significant reliance on academic expertise, had suggested that if knowledge could win wars, the labour of academic staff could be considered to normally have social and economic value to the nation. In 1951 Conant had no way of foreseeing that steps made, in this light, at Federal level during and after the war, would culminate in the 1957 Review of Universities in Australia, chaired by Sir Keith Murray, and the injection of a large amount of funding into the university system. Conant’s confidential report to the Carnegie Corporation does show that he saw the system in desperate need of funding, which wasa reality that everyone agreed upon.1 The long debate included options for university funding and the potential change to the character of universities if the community, rather than the cloister, was to determine the purpose and character of knowledge. Conant’s report reflects this debate, centring (as many other participants did as well) on the value universities would gain if they were more obviously useful and relevant to industry and if their reputation was less stained by elitism and arrogance. Conant could not gather sufficient data in his visit to identify the nuances of this long discussion nor could he see the depth and spread of its influence over the decade or so preceding his visit. As a result, his particular agenda seems to obscure the perception of the threat that change provoked to some of the traditional values associated with academic work. To consider the debate and the character of academic work in the university scene that Conant fleetingly visited, we need to look back just a few years to another, but very different, visitor to the Australian system.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

At our last meeting I strongly suggested that you learn some of the other things your micro workstation could do. To undertake those tasks, you need software, and we all know the high price tag of our newest form of enhanced library productivity.