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Honeycombs enjoy wide use in various engineering applications. The emergence of additive manufacturing (AM) as a method of customisable of parts has enabled the reinvention of the honeycomb structure. However, research on in-plane compressive performance of both classical and new types of honeycombs fabricated via AM is still ongoing. Several important findings have emerged over the past years, with significance for the AM community and a review is considered necessary and timely. This paper aims to review the in-plane compressive performance of AM honeycomb structures.

This paper provides a state-of-the-art review focussing on the in-plane compressive performance of AM honeycomb structures, covering both polymers and metals. Recently published studies, over the past six years, have been reviewed under the specific theme of in-plane compression properties.

The key factors influencing the AM honeycombs' in-plane compressive performance are identified, namely the geometrical features, such as topology shape, cell wall thickness, cell size and manufacturing parameters. Moreover, the techniques and configurations commonly used for geometry optimisation toward improving mechanical performance are discussed in detail. Current AM limitations applicable to AM honeycomb structures are identified and potential future directions are also discussed in this paper.

This work evaluates critically the primary results and findings from the published research literature associated with the in-plane compressive mechanical performance of AM honeycombs.

The purpose of this paper is to examine the relation between estate transformations produced during the governments of the Citizen Revolution (CR) in Ecuador (2007-2017) and welfare regime transformations.

The CR’s project registers an array of specificities that make it a relevant case study to understand it. Among them, it articulated the transformation of the development model with a comprehensive state reform: emphasized both the modernization of the state and the productive structure, and the creation of the basic pillars of a welfare state. The ambitious project materialized in an ambivalent manner, revealing accomplishments and limitations.

The recovery of resources for the state, the efficient organization of resources, decentralization and deconcentration processes, public administration transformations and policy de-corporatization processes accompanied and even propelled important achievements in the social sphere in terms of decommodification, stratification, commodification and defamiliarization. Ecuador’s starting point, as a small and impoverished country with pubic and communal goods and services dismantled through neoliberal reforms, was quite precarious. But, progress was made. Beyond the identified limitations, its accomplishments must be highlighted because they are novel in comparison to other progressive government experiences, especially in the context of Central Andean countries.

This article vindicates the need to link state transformation processes to welfare regime transformations, as well as the academic literature that informs both fields. The description of what took place in Ecuador in the field of social welfare during the ten years of the CR continues to confirm the theoretical potential of the concept of welfare regime with the necessary translations and appropriations that allow for the analysis of countries in the region. It enables an approach to a more theoretically and methodologically elusive object that is at the same time tremendously potent in analytical terms and in its contributions to social transformations. An object that alludes to areas gravely affected during neoliberal hegemony, linked to public institutionality, state capacity and state autonomy. This is why everything that affects the state and the management of public goods and services must be incorporated into the analysis.

This paper presents an experimental investigation in establishing the relationship between FDM process parameters and tensile strength of polycarbonate (PC) samples using the I-Optimal design.

I-optimal design methodology is used to plan the experiments by means of Minitab-17.1 software. Samples are manufactured using Stratsys FDM 400mc and tested as per ISO standards. Additionally, an artificial neural network model was developed and compared to the regression model in order to select an appropriate model for optimisation. Finally, the genetic algorithm (GA) solver is executed for improvement of tensile strength of FDM built PC components.

This study demonstrates that the selected process parameters (raster angle, raster to raster air gap, build orientation about Y axis and the number of contours) had significant effect on tensile strength with raster angle being the most influential factor. Increasing the build orientation about Y axis produced specimens with compact structures that resulted in improved fracture resistance.

The fitted regression model has a p-value less than 0.05 which suggests that the model terms significantly represent the tensile strength of PC samples. Further, from the normal probability plot it was found that the residuals follow a straight line, thus the developed model provides adequate predictions. Furthermore, from the validation runs, a close agreement between the predicted and actual values was seen along the reference line which further supports satisfactory model predictions.

This study successfully investigated the effects of the selected process parameters - raster angle, raster to raster air gap, build orientation about Y axis and the number of contours - on tensile strength of PC samples utilising the I-optimal design and ANOVA. In addition, for prediction of the part strength, regression and ANN models were developed. The selected ANN model was optimised using the GA-solver for determination of optimal parameter settings.

The proposed ANN-GA approach is more appropriate to establish the non-linear relationship between the selected process parameters and tensile strength. Further, the proposed ANN-GA methodology can assist in manufacture of various industrial products with Nylon, polyethylene terephthalate glycol (PETG) and PET as new 3DP materials.

One of the biggest challenges in the health sector is that of costs compared to economic resources and the quality of services. Hospitals register a progressive increase in expenditure due to the aging of the population. In fact, hip and knee arthroplasty surgery are mainly due to primary osteoarthritis that affects the elderly population. This study was carried out with the aim of analysing the introduction of the fast track surgery protocol, through the lean Six Sigma, on patients undergoing knee and hip prosthetic replacement surgery. The goal was to improve the arthroplasty surgery process by reducing the average length of stay (LOA) and hospital costs

Lean Six Sigma was applied to evaluate the arthroplasty surgery process through the DMAIC cycle (define, measure, analyse, improve and control) and the lean tools (value stream map), adopted to analyse the new protocol and improve process performance. The dataset consisted of two samples of patients: 54 patients before the introduction of the protocol and 111 patients after the improvement. Clinical and demographic variables were collected for each patient (gender, age, allergies, diabetes, cardiovascular diseases and American Society of Anaesthesiologists (ASA) score).

The results showed a 12.70% statistically significant decrease in LOS from an overall average of 8.72 to 7.61 days. Women patients without allergies, with a low ASA score not suffering from diabetes and cardiovascular disease showed a significant a reduction in hospital days with the implementation of the FTS protocol. Only the age variable was not statistically significant.

The introduction of the FTS in the orthopaedic field, analysed through the LSS, demonstrated to reduce LOS and, consequently, costs. For each individual patient, there was an economic saving of € 445.85. Since our study takes into consideration a dataset of 111 patients post-FTS, the overall economic saving brought by this study amounts to €49,489.35.

This study investigates an under-researched yet fundamental question of how a developed country multinational enterprises (DMNE) perceives and manages political risks when undertaking infrastructure projects in the emerging markets (EMs).

The authors use an abduction-based qualitative research approach to analyze six international project operations of a multinational enterprise originating from Finland in five EMs.

The findings suggest that the overall nature of political risks in EMs is not the same, except few political risk factors that are visible in most EMs. Consequently, the applied risk management mechanisms vary between EMs, except with few common mechanisms. The authors develop an integrative analytical framework of political risk management based on the findings.

This paper is one of the first studies to identify political risk factors for western MNEs while undertaking international project operations and link them to reduction mechanisms used by them. The authors go beyond the notion of risk being conceptualized at a general level and evaluate 20 specific political risk factors referred to in extant literature. The authors further link these political risk factors with both social exchange and transaction cost theories conceptually as well as empirically. Finally, the authors develop a relatively comprehensive analytical framework of political risk management based on the case projects' findings that combine several strands of literature, including the social exchange theory, transaction cost theory, international market entry, project management and finance literature streams.

Simulations exist for the prediction of the behaviour of building structural systems under fire, including two-way coupled fire-structure interaction. However, these simulations do not include detailed models of the connections, whereas these connections may impact the overall behaviour of the structure. Therefore, this paper proposes a two-scale method to include screw connections.

The two-scale method consists of (a) a global-scale model that models the overall structural system and (b) a small-scale model to describe a screw connection. Components in the global-scale model are connected by a spring element instead of a modelled screw, and the stiffness of this spring element is predicted by the small-scale model, updated at each load step. For computational efficiency, the small-scale model uses a proprietary technique to model the behaviour of the threads, verified by simulations that model the complete thread geometry, and validated by existing pull-out experiments. For four screw failure modes, load-deformation behaviour and failure predictions of the two-scale method are verified by a detailed system model. Additionally, the two-scale method is validated for a combined load case by existing experiments, and demonstrated for different temperatures. Finally, the two-scale method is illustrated as part of a two-way coupled fire-structure simulation.

It was shown that proprietary ”threaded connection interaction” can predict thread relevant failure modes, i.e. thread failure, shank tension failure, and pull-out. For bearing, shear, tension, and pull-out failure, load-deformation behaviour and failure predictions of the two-scale method correspond with the detailed system model and Eurocode predictions. Related to combined load cases, for a variety of experiments a good correlation has been found between experimental and simulation results, however, pull-out simulations were shown to be inconsistent.

More research is needed before the two-scale method can be used under all conditions. This relates to the failure criteria for pull-out, combined load cases, and temperature loads.

The two-scale method bridges the existing very detailed small-scale screw models with present global-scale structural models, that in the best case only use springs. It shows to be insightful, for it contains a functional separation of scales, revealing their relationships, and it is computationally efficient as it allows for distributed computing. Furthermore, local small-scale non-convergence (e.g. a screw failing) can be handled without convergence problems in the global-scale structural model.

As an essential part of mainstream Western development economics, the trickle-down theory originates from the behavioral choices and iterations of thought on conflicts of interest in the evolution of remuneration structure in Western countries. The fundamental flaw of the logic of this theory is that it conceals the inherent implication of social systems and the essential characteristics of social structures.

This paper examines the relationships among economic growth, income distribution and poverty from the perspective of social relations of production – the nature of production relations determines the nature of distribution relations and further determines the essence of trickle-down development, and ownership is the core mechanism for realizing the trickle-down effect.

The stagnation or smoothness of the trickle-down effect in different economies is essentially subject to the logic of “development for whom”, which is determined by ownership relationship.

To be more specific, “development for capitalists” and “development for the people” indicate two distinctly different economic growth paths. The former starts with private ownership and follows a bottom-up negative trickle-down path that inevitably leads to polarization, while the latter starts with public ownership and follows a top-down positive trickle-down path that will lead to common prosperity in the end.

The purpose of the article is to outline the insights provided by Alan Fox in Man Mismanagement in relation to the rise of the New Right political economy and the spread of unitarist managerialism. The article assesses the contemporary work and employment relations implications of mismanagement arising from a “second wave” of the New Right ideology from 2010 in the UK.

Responding to the Special Issue on Alan Fox, the article focuses on Alan Fox's book Man Mismanagement, considering industrial relations developments arising between the 1st (1974b) and 2nd (1985) editions relating to the political rise of the New Right. It reviews various literature that illustrates the contemporary IR relevance of the book and Fox's insights.

The New Right’s ideology has further fragmented work, disjointed labour rights and undermined collective industrial relations institutions, and macho mismanagement praxis is even more commonplace, compared to when Fox wrote Man Mismanagement. The stripping away of the institutional architecture of IR renders the renewal of pluralist praxis, like collective bargaining and other forms of joint regulation of work, a formidable task.

The value of the article relates to the identification of dramatic historical industrial relations events and change in the UK in Alan Fox's book Man Mismanagement, most notably relating to the rise to power of the Thatcherite New Right in 1979. Originality is evidenced by the authors’ drawing on Fox's ideas and assessing the implications of the “second wave” of the New Right in the contemporary industrial relations (IR) context of the 2020s under the conceptual themes of fragmented work, disjointed labour rights and undermined collectivism.

Large-scale data analytics have raised a number of ethical concerns. Many of these were introduced in a seminal paper by boyd and Crawford and have been developed since by others (boyd & Crawford, 2012; Lagoze, 2014; Martin, 2015; Mittelstadt, Allo, Taddeo, Wachter, & Floridi, 2016). One such concern which is frequently recognised but under-analysed is the focus on correlation of data rather than on the causative relationship between data and results. Advocates of this approach dismiss the need for an understanding of causation, holding instead that the correlation of data is sufficient to meet our needs. In crude terms, this position holds that we no longer need to know why X+Y=Z. Merely acknowledging that the pattern exists is enough.

In this chapter, the author explores the ethical implications and challenges surrounding a focus on correlation over causation. In particular, the author focusses on questions of legitimacy of data collection, the embedding of persistent bias, and the implications of future predictions. Such concerns are vital for understanding the ethical implications of, for example, the collection and use of ‘big data’ or the covert access to ‘secondary’ information ostensibly ‘publicly available’. The author’s conclusion is that by failing to consider causation, the short-term benefits of speed and cost may be countered by ethically problematic scenarios in both the short and long term.