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Laser sintering of polyamide lattice-based lightweight fairing components for subsequent racetrack testing requires a high quality and a reliable design. Hence, the purpose of this study was to develop a design methodology for such additively manufactured prototypes, considering efficient generation and structural simulation of boundary conformal non-periodic lattices, optimization of production parameters as well as experimental validation.

Multi-curved, sandwich structure-based demonstrators were designed, simulated and experimentally tested with boundary conformal lattice cells. The demonstrator’s non-periodic lattice cells were simplified by forward homogenization processes. To represent the stiffness of the top and bottom face sheet, constant isotropic and mapped transversely isotropic simulation approaches were compared. The dimensional accuracy of lattice cells and demonstrators were measured with a gauge caliper and a three-dimensional scanning system. The optimized process parameters for lattice structures were transferred onto a large volume laser sintering system. The stiffness of each finite element analysis was verified by an experimental test setup including a digital image correlation system.

The stiffness prediction of the mapped was superior to the constant approach and underestimated the test results with −6.5%. Using a full scale fairing the applicability of the development process was successfully demonstrated.

The design approach elaborated in this research covers aspects from efficient geometry generation over structural simulation to experimental testing of produced parts. This methodology is not only relevant in the context of motor sports but is transferrable for all additively manufactured large scale components featuring a complex lattice sub-structure and is, therefore, relevant across industries.

The purpose of this paper is to present the result of calculations that were performed to estimate the structural weight of the passenger aircraft using novel technological solution. Mass penalty resulting from the installation of the fuselage boundary layer ingestion device was needed in the CENTRELINE project to be able to estimate the real benefits of the applied technology.

This paper focusses on the finite element analysis (FEA) of the fuselage and wing primary load-carrying structures. Masses obtained in these analyses were used as an input for the total structural mass calculation based on semi-empirical equations.

Combining FEA with semi-empirical equations makes it possible to estimate the mass of structures at an early technology readiness level and gives the possibility of obtaining more accurate results than those obtained using only empirical formulas. The applied methodology allows estimating the mass in case of using unusual structural solutions, which are not covered by formulas available in the literature.

Accurate structural mass estimation is possible at an earlier design stage of the project based on the presented methodology, which allows for easier and less costly changes in designed aircrafts.

The presented methodology is an original method of mass estimation based on a two-track approach. The analytical formulas available in the literature have worked well for aeroplanes of conventional design, but thanks to the connection with FEA presented in this paper, it is possible to estimate the structure mass of aeroplanes using unconventional technological solutions.

This paper aims to investigate the impact of combining grain-oriented electrical steel (GOES) grades on specific iron losses and the flux density distribution within a single-phase magnetic core.

This paper presents the results of finite-element method (FEM) simulations investigating the impact of mixing two different GOES grades on losses of a single-phase magnetic core. The authors used different models: a 3D model with a highly detailed geometry including both saturation and anisotropy, as well as a simplified 2D model to save computation time. The behavior of the flux distribution in the mixed magnetic core is analyzed. Finally, the results from the numerical simulations are compared with experimental results.

The specific iron losses of a mixed magnetic core exhibit a nonlinear decrease with respect to the GOES grade with the lowest losses. Analyzing the magnetic core behavior using 2D and 3D FEM shows that the rolling direction of the GOES grades plays a critical role on the nonlinearity variation of the specific losses.

The novelty of this research lies in achieving an optimum trade-off between the manufacturing cost and the core efficiency by combining conventional and high-performance GOES grade in a single-phase magnetic core.

The purpose of this work is to comparatively study human resources management (HRM) areas in Brazil, at the national level, analyzing how companies considered labor market and labor relations aspects when building their strategies and when configuring people management models in place in the country (2014–2019), based on local conditions.

The subject was approached through qualitative analysis, encompassing document survey, systematic literature review, specialists' panel discussions, eight focus groups (43 human resources [HR] managers), interviews (16 union members), applying institutional approach to people management.

In regards to labor market and unions, HR areas faced different conditions across Brazilian regions. They have dealt with those influences on their strategic and quotidian decisions in an unstructured fashion. HR areas remain constructed as traditional, adjuvant and far from strategic level. In the institutionalization process – normative isomorphism – a professional HR jargon use was identified. HR areas usually act in collective bargaining, resorting to specialized professionals or consulting companies. During the economic crisis, HR professionals' attitude had a reactive nature, responding to organizations leadership, with little dedication to the emerging context.

This work enables important players like HR managers, union members and specialists in public policies to interpret the institutionalization phenomena of practices related to management, labor market and labor relations in the country.

Understanding the effects of the relations among state, companies and unions allows the different power vectors, acting upon the institutionalization process of people management areas in the Brazilian case, to be outlined.

This study applies the institutional approach to understand the economic and social heterogeneity affecting organizations in Brazil. It enhances the knowledge on HRM areas scope and their articulation toward labor market and relations.

The purpose of this paper is to settle the methodological debate on the decomposition of value added in gross exports, proposing a standard, exposing the drawbacks of the alternatives and quantifying the differences.

This paper systematizes the analytical framework and assesses and quantifies the various methodologies and its main differences.

The decomposition method of Borin and Mancini (2023), using a source-based approach and an exporting country perspective, should be considered as the standard for decomposing the value added in gross exports. This study finds that alternative approaches and perspectives are methodologically inferior, and that tailored perspectives do not provide an increase in accuracy that compensates their drawbacks.

This paper’s contribution is fourfold: it rejects the alleged equivalence between approaches and perspectives, defending the superiority of a particular method, approach and perspective; it gives quantitative examples of the differences between them; it proves that the drawbacks of tailored perspectives do not compensate their alleged accuracy (as they do not result in big quantitative differences with the standard perspective); and it argues that no valid standard decomposition can forego the calculation of value added exported, which requires the expression of exports in terms of final demand.

Studies of entrepreneurial intentions (EIs) have become increasingly common, informed usually by Ajzen’s (1991) theory of planned behaviour (TPB). Although the TPB postulates that beliefs determine EIs, the contents of the beliefs have not been properly studied, leaving EIs’ cognitive underpinnings and cognitive approaches to influencing EIs unclear. To clarify the TPB/EI-belief nexus, the study examines the conceptual background of entrepreneurial cognitions and elicits the beliefs of a group of nascent micro entrepreneurs (NMEs) to compare them with their TPB attitudes and EIs, facilitating assessing their mutual consistency as implied by the TBP.

The respondents are entrepreneurial novice clients of a micro business advisory organisation. Their TPB attitudes and EIs were measured using standard TPB/EI methods. Comparative causal mapping (CCM) combined with semi-structured interviewing was used to reveal the NMEs’ typical belief systems, presented as aggregated cause maps.

The NMEs have uniform, relatively detailed belief systems about entrepreneurship and micro business. The belief systems are consistent with theory- and context-based expectations and logically aligned with the NMEs’ expressed TPB attitudes and EIs. CCM provides an accessible method for studying contents of entrepreneurial cognitions.

It was not possible to study “entrepreneurship-negative” respondents or the intensity or origins of some specific beliefs.

Diagnosing and better understanding beliefs can benefit entrepreneurship education and development, in general or connected with TPB/EI studies.

The study reveals entrepreneurial belief systems systematically, evidently not done before generally or in terms of “everyday” micro entrepreneurship or TPB. It clarifies and supports the TPB notion that beliefs underpin actors’ attitudes and intentions.

This study aims to investigate the occurrence of the decoy effect in stock investment decisions based on fundamental analysis.

In this study, the decoy effect was investigated by applying two questionnaires, one of them with the presence of a decoy alternative, to a set of 224 respondents with knowledge of business fundamentals, simulating investment decisions in stocks of companies listed on the Brazilian Stock Exchange. The data analysis was performed using the Fisher's exact test, Student's t-test and ANOVA. The research also aimed to detect a potential relationship between the variables gender, age, degree and professional experience with the type of decision made.

The results pointed to the occurrence of the decoy effect when analysing the general response data. However, such evidence was not confirmed when the sample was analysed by classes (gender, course, age and professional experience). There is no statistical evidence that the decoy effect influences classes.

The recent decoy effect literature is little explored in investment decision-making. This study is unique in examining the decoy effect in investment decisions in the Brazilian context.

There are over 40 million amputees globally with more than 185,000 Americans losing their limbs every year. For most of the world, prosthetic devices remain too expensive and uncomfortable. This paper aims to outline advancements made by a multidisciplinary research group, interested in advancing the restoration of human motion through accessible lower limb prostheses.

Customization, comfort and functionality are the most important metrics reported by prosthetists and patients. The work of this paper presents the design and manufacturing of a custom made, cost-effective and functional three-dimensional (3D) printed transtibial prosthesis monocoque design. The design of the prosthesis integrates 3D imaging, modelling and optimization techniques coupled with additive manufacturing.

The successful fabrication of a functional monocoque prosthesis through 3D printing indicates the workflow may be a solution to the worldwide accessibility crisis. The digital workflow developed in this work offers great potential for providing prosthetic devices to rural communities, which lack access to skilled prosthetic physicians. The authors found that using the workflow together with 3D printing, this study can create custom monocoque prostheses (Figure 16). These prostheses are comfortable, functional and properly aligned. In comparison with traditional prosthetic devices, the authors slowered the average cost, weight and time of production by 95%, 55% and 95%, respectively.

This novel digital design and manufacturing workflow has the potential to democratize and globally proliferate access to prosthetic devices, which restore the patient’s mobility, quality of life and health. LIMBER’s toolbox can reach places where proper prosthetic and orthotic care is not available. The digital workflow reduces the cost of making custom devices by an order of magnitude, enabling broader reach, faster access and improved comfort. This is particularly important for children who grow quickly and need new devices every few months or years, timely access is both physically and psychologically important.

In this manuscript, the authors show the application of digital design techniques for fabricating prosthetic devices. The proposed workflow implements several advantageous changes and, most importantly, digitally blends the three components of a transtibial prosthesis into a single, 3D printable monocoque device. The development of a novel unibody transtibial device that is properly aligned and adjusted digitally, greatly reduces the number of visits an amputee must make to a clinic to have a certified prosthetist adjust and modify their prosthesis. The authors believe this novel workflow has the potential to ease the worldwide accessibility crisis for prostheses.

The purpose of this paper is to identify the relationship of career anchors with three aspects: the millennials’ professional skills, the millennials’ awareness of the replacement of jobs with new technologies and the technological stress in the millennials’ working environment.

The responses of 200 questionnaires were analyzed using descriptive and variance analysis techniques.

Among the three hypotheses raised, two were confirmed, showing that these young people recognize the development of professional skills through new technologies, but are not highly sensitive to the stress associated with technological innovations.

The paper contributes to a recent debate, which emphasizes the impact of the application of new technologies on the nature of study and employment levels.

The purpose of this study concerns numerical studies and experimental validation of the mechanical behavior of hybrid specimens. These kinds of composite specimens are made up of thin carbon and glass substrates on which some Macro Fiber Composite^® (MFC) piezoelectric patches are glued. A proper design and manufacturing of the hybrid specimens as well as testing activities have been performed. The research activity has been carried out under the FutureWings project, funded by the European Commission within the 7th Framework.

The paper describes the basic assumptions made to define specimen geometries and to carry out experimental tests. Finite element (FE) results and experimental data (laser technique measurements) have been compared: it shows very good agreement for the displacements’ distribution along the specimens.

Within the objectives of the project, the study of passive and active deformation characteristics of the hybrid composite material has provided reference technical data and has allowed for the correct adaptation of the FE models. More in particular, using the hybrid specimens, both the bending deformations and the torsion deformations have been studied.

The deformation capability of the hybrid specimens will be used in the development of prototypical three-dimensional structures, that, through the electrical control of the MFC patches, will be able to change the curvature of their cross section or will be able to change the angle of torsion along their longitudinal axis.

The design of nonstandard specimens and the tests executed represent a novelty in the field of structures using piezoelectric actuators. The numerical and experimental data of the present research constitute a small step forward in the field of smart materials technology.