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Many additively manufactured parts suffer from reduced interlayer strength. This anisotropy is necessarily tied to the orientation during manufacture. When individual features on a part have conflicting optimal orientations, the part is unavoidably compromised. This paper aims to demonstrate a strategy in which conflicting features can be functionally separated into “co-parts” which are individually aligned in an optimal orientation, selectively reinforced with continuous fiber, printed simultaneously and, finally, assembled into a composite part with substantially improved performance.

Several candidate parts were selected for co-part decomposition. They were printed as standard fused filament fabrication plastic parts, parts reinforced with continuous fiber in one plane and co-part assemblies both with and without continuous fiber reinforcement (CFR). All parts were loaded until failure. Additionally, parts representative of common suboptimally oriented features (“unit tests”) were similarly printed and tested.

CFR delivered substantial improvement over unreinforced plastic-only parts in both standard parts and co-part assemblies, as expected. Reinforced parts held up to 2.5x the ultimate load of equivalent plastic-only parts. The co-part strategy delivered even greater improvement, particularly when also reinforced with continuous fiber. Plastic-only co-part assemblies held up to 3.2x the ultimate load of equivalent plastic only parts. Continuous fiber reinforced co-part assemblies held up to 6.4x the ultimate load of equivalent plastic-only parts. Additionally, the thought process behind general co-part design is explored and a vision of simulation-driven automated co-part implementation is discussed.

This technique is a novel way to overcome one of the most common challenges preventing the functional use of additively manufactured parts. It delivers compelling performance with continuous carbon fiber reinforcement in 3D printed parts. Further study could extend the technique to any anisotropic manufacturing method, additive or otherwise.

The purpose of the work is to provide a comprehensive review of the digital image correlation (DIC) technique for those who are interested in performing the DIC technique in the area of manufacturing.

No methodology was used because the paper is a review article.

no fundings.

Herein, the historical development, main strengths and measurement setup of DIC are introduced. Subsequently, the basic principles of the DIC technique are outlined in detail. The analysis of measurement accuracy associated with experimental factors and correlation algorithms is discussed and some useful recommendations for reducing measurement errors are also offered. Then, the utilization of DIC in different manufacturing fields (e.g. cutting, welding, forming and additive manufacturing) is summarized. Finally, the current challenges and prospects of DIC in intelligent manufacturing are discussed.

This paper aims to present an investigation into the variation of scan vector hatch rotation strategies in selective laser melting (SLM), focussing on how it effects density, surface roughness, tensile strength and residual stress.

First the optimum angle of hatch vector rotation is proposed by analysing the effect of different increment angles on distribution of scan vectors. Sectioning methods are then used to determine the effect that the chosen strategies have on the density of the parts. The top surface roughness was analysed using optical metrology, and the tensile properties were determined using uni-axial tensile testing. Finally, a novel multi-support deflection geometry was used to quantify the effects of rotation angles on residual stress.

The results of this research showed that the hatch rotation angle had little effect on the density, top surface roughness and strength of the parts. The greatest residual stress deflection was measured parallel to unidirectional scan vectors. The use of hatch rotations other than alternating 90° showed little benefit in lowering the magnitude of residual stresses. However, the use of rotation angles with a good suitability measure distributes stresses in all directions more evenly for certain part geometries.

All samples produced in this work were made from commercially pure titanium, therefore care must be taken when applying these results to other materials.

This paper serves to increase the understanding of SLM scanning strategies and their effect on the properties of the material.

In the 1990s, following the challenges imposed by globalisation, the liner shipping industry experienced profound changes, leading major carriers to create ad-hoc logistics business-units. Nevertheless the vertical integration of shipping lines along the transport chain faced important entry barriers in various regions.This paper aims at analysing the impact of such barriers on carriers’ pathways of expansion in the logistics business. It mainly focuses on the East-Asian market, as a relevant empirical case in which important institutional and socio-political obstacles are still in force .Main results disclose sui-generis paths of expansion achieved by major carriers, in contrast with linear constructs of time and space proposed by classical TNC theories. In such respect, port operations reveal to be the most critical stage of the chain. The ‘sidestep’ of the port phase, leading to investments in other on-shore activities (warehousing, inland terminals, etc.) as well as the implementation of aggressive financial campaigns (acquisitions and takeovers), reveal the unfaltering will of top shipping lines: the quick achievement of a successful vertical and horizontal expansion despite environmental obstacles.

This article addresses the relationship of universities to their changing regulatory environments internationally.

This article updates analysis published in 2004 exploring the contrasting modes of, and key trends in, regulation of higher education across eight OECD (Organisation for Economic Co-operation and Development) states. The article offers a wider analysis of the changing patterns of regulation rooted in mutuality, oversight, competition and design, and the implications for the management of higher education institutions.

Since 2004, higher education has seen more growth in oversight-based and competition-based regulation, but also some decentralization of regulation as an increasing cast of actors, many international and transnational in character, have asserted themselves in key aspects of the regulatory environment. This article explores the implications of these changes in the regulatory mix over higher education for the ways that universities manage their regulatory environment, arguing first, that there is significant evidence of meta-regulatory approaches to regulating universities, and second, that such a meta-regulatory approach is consistent with an emphasis on university autonomy, raising a challenge for universities in how to use the autonomy (variable by country) they do have to manage their environment.

This article offers an original analysis of how universities might most appropriately respond, deploying their autonomy, however variable, to address their external regulatory environment. The author suggests we might increasingly see the external regulatory environment as meta-regulatory in character and universities making more use of reflexive governance processes.

This paper aims to explore how the phenomena of corruption and fraud in the public sector have been portrayed in the literature using the Audit Society Framework (Power, 1997).

The authors conducted a structured literature review (Massaro et al., 2016) to unveil relevant literature in the area of corruption and fraud in the public sector.

Results highlight that the literature using “The Audit Society” theory is still scant. Notwithstanding the call for a more decisive role of auditors in fighting corruption and fraud, much is still to be discovered about consequences of auditing and what “good quality” is.

The main limitation is that only literature in English has been included.

This paper helps practitioners and policymakers to take and implement informed decisions with regards to the fight against fraud and corruption.

In calling for more research in the domain of audit, fraud and corruption in the public sector, this paper promotes a higher focus of society on public interest and the common good.

This paper investigates one part of The Audit Society related to corruption and fraud, topics that are still very underdeveloped and unexplored by researchers. From the findings the authors suggest possible new avenues for further research.

The paper aims to promote the development of intelligent materials and the 4D printing technology by introducing recent advances and applications of additive layered manufacturing (ALM) technology of intelligent materials and the development of the 4D printing technology. Also, an arm-type ALM technology of shape memory polymer (SMP) with thermosetting polyurethane is briefly introduced.

This paper begins with an overview of the development and applications of intelligent materials around the world and the 4D printing technology. Then, the authors provide a brief outline of their research on arm-type ALM technology of SMP with thermosetting polyurethane.

The paper provides the recent developments and applications of intelligent materials and 4D printing technology. Then, it is suggested that intelligent materials mixed with different functional materials will be developed, and these types of materials will be more suitable for 4D printing.

This paper overviews the current developments and applications of intelligent materials and its use in 4D printing technology, and briefly states the authors’ research on arm-type ALM technology of SMP with thermosetting polyurethane.

The “chiralisation” of Euclidean polygonal tessellations is a novel, recent method which has been used to design new auxetic metamaterials with complex topologies and improved geometric versatility over traditional chiral honeycombs. This paper aims to design and manufacture chiral honeycombs representative of four distinct classes of 2D Euclidean tessellations with hexagonal rotational symmetry using fused-deposition additive manufacturing and experimentally analysed the mechanical properties and failure modes of these metamaterials.

Finite Element simulations were also used to study the high-strain compressive performance of these systems under both periodic boundary conditions and realistic, finite conditions. Experimental uniaxial compressive loading tests were applied to additively manufactured prototypes and digital image correlation was used to measure the Poisson’s ratio and analyse the deformation behaviour of these systems.

The results obtained demonstrate that these systems have the ability to exhibit a wide range of Poisson’s ratios (positive, quasi-zero and negative values) and stiffnesses as well as unusual failure modes characterised by a sequential layer-by-layer collapse of specific, non-adjacent ligaments. These findings provide useful insights on the mechanical properties and deformation behaviours of this new class of metamaterials and indicate that these chiral honeycombs could potentially possess anomalous characteristics which are not commonly found in traditional chiral metamaterials based on regular monohedral tilings.

To the best of the authors’ knowledge, the authors have analysed for the first time the high strain behaviour and failure modes of chiral metamaterials based on Euclidean multi-polygonal tessellations.

The purpose of this paper is to reconsider, from a historical perspective, New Zealand’s reputation as a country largely without corruption, with particular reference to the colonial government’s confiscation of Māori land in the 19^th century and beyond.

This paper is based on published historical commentary.

The findings are that much of the Māori land confiscation was rendered legal for illegitimate purposes, and that the colonial and successive New Zealand governments abrogated the country’s foundational document, the Treaty of Waitangi, signed between the colonial government and many Māori chiefs in 1840. Adverse consequences for Māori have been felt to this day, despite the Treaty settlements process that began with the Māori renaissance in the mid-1970s.

The academic analysis of corruption in New Zealand has seldom if ever adopted this historical perspective.