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The advancement of additive manufacturing technologies has resulted in producing parts of high quality and reduced manufacturing time. This paper aims to achieve a simultaneous optimal solution for build time and surface roughness as the output data and also to find the best values for the input data consisting of build orientation, extrusion width, layer thickness, infill percentage and raster angle.

For this purpose, the effects of process parameters on the response variables were investigated by the design of experiments approach to develop empirical models using response surface methodology. The experimental parts of this research were conducted using an inexpensive and locally assembled fused filament fabrication (FFF) machine. A total of 50 runs for 4 different geometries, namely, cylinder, prism, 3DBenchy and twist gear vase, were performed using the rotatable central composite design, and each process parameters were investigated in two levels to develop empirical models. Also, a novel optimization method, namely, the posterior-based method, was accomplished to find the best values for the response variables.

The results demonstrated that not only the build orientation and layer thickness have notable effects on both response variables but also build time is dependent on extrusion width and infill percentage. Low infill percentage and high extrusion width resulted in increasing build time. By reducing layer thickness and infill percentage while increasing extrusion width, parts of high-quality surface finish and reduced built time were produced. Optimum process parameters were found to be of build direction of 0°, extrusion width of 0.61 mm, layer thickness of 0.22 mm, infill percentage of 20% and raster angle of 0°.

Through the developed empirical models and by minimizing build orientation and layer thickness, and also considerations for process parameters, parts of high-quality surface finish and reduced built time could be produced on FFF machines. To compensate for increased build time because of reduction in layer thickness, extrusion width and infill percentage must have their maximum and minimum value, respectively.

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.

This paper reviews the synergy of Industry 4.0 and additive manufacturing (AM) and discusses the integration of data-driven manufacturing systems and product service systems as a key component of the Industry 4.0 revolution. This paper aims to highlight the potential effects of Industry 4.0 on AM via tools such as digitalisation, data transfer, tagging technology, information in Industry 4.0 and intelligent features.

In successive phases of industrialisation, there has been a rise in the use of, and dependence on, data in manufacturing. In this review of Industry 4.0 and AM, the five pillars of success that could see the Internet of Things (IoT), artificial intelligence, robotics and materials science enabling new levels of interactivity and interdependence between suppliers, producers and users are discussed. The unique effects of AM capabilities, in particular mass customisation and light-weighting, combined with the integration of data and IoT in Industry 4.0, are studied for their potential to support higher efficiencies, greater utility and more ecologically friendly production. This research also illustrates how the digitalisation of manufacturing for Industry 4.0, through the use of IoT and AM, enables new business models and production practices.

The discussion illustrates the potential of combining IoT and AM to provide an escape from the constraints and limitations of conventional mass production whilst achieving economic and ecological savings. It should also be noted that this extends to the agile design and fabrication of increasingly complex parts enabled by simulations of complex production processes and operating systems. This paper also discusses the relationship between Industry 4.0 and AM with respect to improving the quality and robustness of product outcomes, based on real-time data/feedback.

This research shows how a combined approach to research into IoT and AM can create a step change in practice that alters the production and supply paradigm, potentially reducing the ecological impact of industrial systems and product life cycle. This paper demonstrates how the integration of Industry 4.0 and AM could reshape the future of manufacturing and discusses the challenges involved.

Several inferential procedures are advocated in the literature. The most commonly used techniques are the frequentist and the Bayesian inferential procedures. Bayesian methods afford inferences based on small data sets and are especially useful in studies with limited data availability. Bayesian approaches also help incorporate prior knowledge, especially subjective knowledge, into predictions. Considering the increasing difficulty in data acquisition, the application of Bayesian techniques can be hugely beneficial to managers, especially in analysing limited data situations like a study of expert opinion. Another factor constraining the broader application of Bayesian statistics in business was computational power requirements and the availability of appropriate analytical tools. However, with the increase in computational power, connectivity and the development of appropriate software programmes, Bayesian applications have become more attractive. This chapter attempts to unravel the applications of the Bayesian inferential procedure in marketing management.

Behavioral economics poses a challenge for the welfare evaluation of choices, particularly those that involve risk. It demands that we recognize that the descriptive account of behavior toward those choices might not be the ones we were all taught, and still teach, and that subjective risk perceptions might not accord with expert assessments of probabilities. In addition to these challenges, we are faced with the need to jettison naive notions of revealed preferences, according to which every choice by a subject expresses her objective function, as behavioral evidence forces us to confront pervasive inconsistencies and noise in a typical individual’s choice data. A principled account of errant choice must be built into models used for identification and estimation. These challenges demand close attention to the methodological claims often used to justify policy interventions. They also require, we argue, closer attention by economists to relevant contributions from cognitive science. We propose that a quantitative application of the “intentional stance” of Dennett provides a coherent, attractive and general approach to behavioral welfare economics.

The diagnosis and management of cancer in people with intellectual disabilities (PWIDs) are fraught with difficulties. The purpose of this paper is to present a case study to highlight these difficulties.

The present case analysis describes the presentation of a 56-year-old man with a profound intellectual disability, who developed recurrent chest infections and died as a result of obstructive pneumonitis.

Despite a presentation over several years and numerous chest X-rays demonstrating a consistent lung abnormality, it was only on postmortem examination that a right-sided lung carcinoma was detected.

The papers have provided an update on the topic in light of recent legislations and management strategies which need to be applied to clinical practice if any improvement is to happen in the care of PWID.