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Metal additive manufacturing is an inherently thermal process, with intense localised heating and for sparse lattice structures, often rapid uneven cooling. Thermal effects influence manufactured geometry through residual stresses and may also result in non-isotropic material properties. This paper aims to increase understanding of the evolution of the temperature field during fabrication of lattice structures through numerical simulation.

This paper uses a reduced order numerical analysis based on “best-practice” compromise found in literature to explore design permutations for lattice structures and provide first-order insight into the effect of these design variables on the temperature field.

Instantaneous and peak temperatures are examined to discover trends at select lattice locations. Insights include the presence of vertical struts reduces overall lattice temperatures by providing additional heat transfer paths; at a given layer, the lower surface of an inclined strut experiences higher temperatures than the upper surface throughout the fabrication of the lattice; during fabrication of the lower layers of the lattice, isolated regions of material can experience significantly higher temperatures than adjacent regions.

Due to the simplifying assumptions and multi-layer material additions, the findings are qualitative in nature. Future research should incorporate additional heat transfer mechanisms.

These findings point towards thermal differences within the lattice which may manifest as dimensional differences and microstructural changes in the built part.

The paper provides qualitative insights into the effect of local geometry and topology upon the evolution of temperature within lattice structures fabricated in metal additive manufacturing.

Additive manufacturing (AM) enables the fabrication of complex geometries beyond the capability of traditional manufacturing methods. Complex lattice structures have enabled engineering innovation; however, the use of traditional computer-aided design (CAD) methods for the generation of lattice structures is inefficient, time-consuming and can present challenges to process integration. In an effort to improve the implementation of lattice structures into engineering applications, this paper aims to develop a programmatic lattice generator (PLG).

The PLG method is computationally efficient; has direct control over the quality of the stereolithographic (STL) file produced; enables the generation of more complex lattice than traditional methods; is fully programmatic, allowing batch generation and interfacing with process integration and design optimization tools; capable of generating a lattice STL file from a generic input file of node and connectivity data; and can export a beam model for numerical analysis.

This method has been successfully implemented in the generation of uniform, radial and space filling lattices. Case studies were developed which showed a reduction in processing time greater than 60 per cent for a 3,375 cell lattice over traditional CAD software.

The PLG method is a novel design for additive manufacture (DFAM) tool with unique advantages, including full control over the number of facets that represent a lattice strut, allowing optimization of STL data to minimize file size, while maintaining suitable resolution for the implemented AM process; programmatic DFAM capability that overcomes the learning curve of traditional CAD when producing complex lattice structures, therefore is independent of designer proficiency and compatible with process integration; and the capability to output both STL files and associated data for numerical analysis, a unique DFAM capability not previously reported.

Biofouling of marine vessels results in significant operational costs, as well as the bio-security risk associated with the transport of marine pests. Biofouling is particularly rapid in sea-chest water intakes due to elevated temperatures and circulating flow. Inspection challenges are exacerbated, as sea chests are difficult to inspect and clean. This paper aims to present a method that utilises the flexibility and low-batch capabilities of additive manufacture to manufacture custom sea-chest inserts that eliminate circulating flow and increase the uniformity of shear stress distributions to enable more constant ablation of anti-biofouling coatings.

An automated design procedure has been developed to optimise sea-chest insert geometry to achieve desirable flow characteristics, while eliminating the necessity for support material in FDM manufacture – thereby significantly reducing build cost and time.

Numerical flow simulation confirms that the fluid-flow approximation is robust for optimising sea-chest insert geometry. Insert geometry can be manipulated to enable support-free additive manufacture; however, as the threshold angle for support-free manufacture increases, the set of feasible sea-chest aspect ratios decreases.

The surface of revolution that defines the optimal insert geometry may result in features that are not compatible with additive manufacture constraints. An alternate geometry is proposed that may be more useful in practice without compromising anti-biofouling properties.

Marine sea-chest biofouling results in significant negative environmental and economic consequence. The method developed in this paper can reduce the negative impact of sea-chest biofouling.

Marine sea-chest biofouling results in significant resource consumption and emissions. The method developed in this paper can reduce the negative impact of sea-chest biofouling.

The method presented in this paper provides an entirely original opportunity to utilise additive manufacture to mitigate the effects of marine biofouling.

Additive manufacture (AM) such as selective laser melting (SLM) provides significant geometric design freedom in comparison with traditional manufacturing methods. Such freedom enables the construction of injection moulding tools with conformal cooling channels that optimize heat transfer while incorporating efficient internal lattice structures that can ground loads and provide thermal insulation. Despite the opportunities enabled by AM, there remain a number of design and processing uncertainties associated with the application of SLM to injection mould tool manufacture, in particular from H13/DIN 1.2344 steel as commonly used in injection moulds. This paper aims to address several associated uncertainties.

A number of physical and numerical experimental studies are conducted to quantify SLM-manufactured H13 material properties, part manufacturability and part characteristics.

Findings are presented which quantify the effect of SLM processing parameters on the density of H13 steel components; the manufacturability of standard and self-supporting conformal cooling channels, as well as structural lattices in H13; the surface roughness of SLM-manufactured cooling channels; the effect of cooling channel layout on the associated stress concentration factor and cooling uniformity; and the structural and thermal insulating properties of a number of structural lattices.

The contributions of this work with regards to SLM manufacture of H13 of injection mould tooling can be applied in the design of conformal cooling channels and lattice structures for increased thermal performance.

The purpose of this paper is to incorporate a blended pedagogical approach to Scientific Writing, and assess its effectiveness in improving students’ writing skills and scientific literacy. Effective writing is vital to the dissemination of scientific information and a critical skill for undergraduate science students. Various pedagogical strategies have been successful in improving writing skills and developing scientific literacy.

Mean scores on draft and revision assignments were examined longitudinally (2013 cohort, n=51) and across cohorts (2011, 2012, and 2013; combined n=94). Domain-specific composite scores were calculated from survey items addressing students’ self-perceptions of knowledge (K), general and scientific writing skills (GWS and SWS), and attitudes (A) related to scientific literacy. Changes in composite scores were analyzed using paired t-tests, and cross-cohort differences were examined via MANOVAs (SPSS, p < 0.05).

Mean scores on revisions following peer review and instructor feedback were significantly higher than those for drafts. Students ' perceptions of their K, GWS, SWS, and A increased significantly over the semester in the 2013 cohort, and were significantly higher in the 2013 cohort than those for the two earlier cohorts. Students identified peer reviews, revisions and other writing assignments, and literature searches as effective learning strategies.

One limitation of the study was that the authors lacked a control group for comparison. Pre-course survey data were only available for the 2013 cohort, and these data were incomplete, particularly with regard to perceptions of attitudes toward science and writing. Instructor feedback was not separated from that obtained through peer review. Thus, it was not possible to determine their respective impacts on students’ scores on revision assignments. Also, the number of writing assignments and peer reviews completed varied among the three cohorts enrolled in Scientific Writing.

Using a blended approach to teaching scientific writing significantly improved students’ writing skills and enhanced their perceptions regarding their knowledge, skills, and abilities related to science and writing. Students identified peer reviews, writing abstracts, and outlining an Introduction as most helpful in improving their SWS. They identified the final peer review, the revision assignment of the Results section, literature searches, and poster presentations of research as most helpful in improving their scientific knowledge and understanding. Engaging students in a variety of pedagogical strategies was successful in achieving specific learning outcomes in an undergraduate human physiology course.

The approach to peer review was more structured than those of previous studies. Engaging students with a variety of teaching and learning strategies improved both writing skills and scientific literacy in undergraduate human physiology.

Using data from a large cross-section of British establishments, we ask how different firm characteristics are associated with the predicted benefits to organizational performance from using team production. To compute the predicted benefits from using team production, we estimate structural models for financial performance, labor productivity, and product quality, treating the firm's choices of whether or not to use teams and whether or not to grant teams autonomy as endogenous. One of the main results is that many firm characteristics are associated with larger predicted benefits from teams to labor productivity and product quality but smaller predicted benefits to financial performance. For example, this is true for union recognition as measured by the number of recognized unions in an establishment. Similarly, when a particular firm characteristic is associated with lower benefits from teams to labor productivity or product quality, the same characteristic is frequently associated with higher predicted benefits to financial performance. This is true for the degree of financial participation and employee ownership and also for establishment size and a number of industries. These results highlight the advantages of analyzing broader measures of organizational performance that are more inclusive of the wide spectrum of benefits and costs associated with teams than the labor productivity measures frequently studied in the teams literature.

I use the 1998–2004 Workplace Employee Relations Survey (WERS) panel data set of British establishments to analyze the effect of team production (either autonomous/self-managed or closely managed) on financial performance. The pattern of evidence is consistent with a positive association between team production in an establishment's largest occupational group and the likelihood of improved financial performance for that establishment. However, the results are mixed concerning whether the positive effects of teams are larger for autonomous teams versus nonautonomous teams.

The purpose of this paper is to explore the experiences of students and teachers who had participated in a postgraduate work-based praxis course within a Master of mental health practice qualification.

This qualitative study used an interpretative phenomenological approach to understand the lived experience of students and course convenors participating in a work-based praxis course. Seven students and two convenors were recruited. Interview and reflective portfolio data were analysed thematically.

The main themes identified were the importance of planning, the value of partnerships, the significance of learning in the workplace and how the facilitation of work-based learning differs from coursework.

Work-based learning within postgraduate coursework qualifications can support higher-level learning, knowledge and skills has received limited attention in the literature. This study supported the value of providing postgraduate students with work-based learning opportunities, resulting in the application of new or advanced skills, within their existing work roles. This study is important, because it provides insights into the student experience of postgraduate work-based learning and the impact of this learning on professional practice.

The purpose of this paper is to understand how Design for Additive manufacturing Knowledge has been developing and its significance to both academia and industry.

In this paper, the authors use a bibliometric approach to analyse publications from January 2010 to December 2020 to explore the subject areas, publication outlets, most active authors, geographical distribution of scholarly outputs, collaboration and co-citations at both institutional and geographical levels and outcomes from keywords analysis.

The findings reveal that most knowledge has been developed in DfAM methods, rules and guidelines. This may suggest that designers are trying to learn new ways of harnessing the freedom offered by AM. Furthermore, more knowledge is needed to understand how to tackle the inherent limitations of AM processes. Moreover, DfAM knowledge has thus far been developed mostly by authors in a small number of institutional and geographical clusters, potentially limiting diverse perspectives and synergies from international collaboration which are essential for global knowledge development, for improvement of the quality of DfAM research and for its wider dissemination.

A concise structure of DfAM knowledge areas upon which the bibliometric analysis was conducted has been developed. Furthermore, areas where research is concentrated and those that require further knowledge development are revealed.

Reports the findings of a study conducted to explain the recent poor performances of the Australian food‐processing industry, by historically analysing the structural determinants and intensity of competition that prevailed in the early 1980s. Covers the period 1979 to 1985 in depth using a research design that incorporates information from both published sources and empirical interviews of senior marketing executives. Using the Porter framework, an accepted approach to the structural analysis of industries, demonstrates that the food industry was one of the most competitive industries in the world in the early 1980s. Attempts to analyse the resultant implications of such competitive pressures on industry performance in the 1990s.