1,720,958 research outputs found
Causal technological model for predicting void fraction and energy consumption in material extrusion process of polylactic acid
No full textThe rapid expansion of Additive Manufacturing (AM) technologies within the framework of Industry 4.0 raises important questions about their sustainability. Specifically, the widespread use of Material Extrusion (MEx) processes for polymeric materials necessitates a thorough evaluation of the possible balance between performance efficiency and sustainability, highlighting the need for further research into optimizing process parameters to ensure high product quality and reduced energy consumption. The present work focuses on Fused Filament Fabrication (FFF) technology, investigating the relationship between sustainability and print quality. A causal technology model is proposed to elucidate this relationship, underlining the impact of process parameters on defect generation and energy use. A real-time monitoring system for energy consumption measurements was employed to create an energy model that accounts for each component of the CreatBot F430 printer. An image analysis procedure was performed on a special configuration of the HIROX RH-2000 digital microscope to determine the void fraction of each sample. An experimental campaign was conducted, producing single-layer samples in polylactic acid (PLA) following a full factorial plan with four process parameters. A void fraction of up to 18 % was observed, with energy consumption per sample ranging between 638 J and 8843 J. Statistical analysis was performed to assess the impact of each process parameter and to determine operational ranges through the Response Surfaces Method. These results showed good agreement with the predicted conditions, demonstrating the model's effectiveness in supporting decision-making processes in technology selection
Advancing sustainability in Electron and laser beam powder Bed Fusion technologies via Innovation: Insights from patent analysis
No full textAdditive manufacturing (AM) technologies continuously evolve in materials and operational
processes. However, challenges related to energy consumption, material reuse efficiency, and the
integration of Circular Economy (CE) principles may impede the overall sustainability of AM
processes. As many industrial sectors adopt AM technologies, there is a growing need for innovative
tools, methods, and frameworks that guide companies toward more sustainable and circular
production practices. This shift involves improving resource efficiency and fostering new Circular
Business Models that emphasize material recovery, product lifecycle extension, and waste
minimization. This study assesses current and future trends in the development of sustainable AM
technologies for processing metal feedstock, based on a comprehensive patent analysis covering the
period from 2004 to 2024. We specifically focus on the sustainability impacts of Electron and Laser
Beam Powder Bed Fusion (PBF-EB, PBF-LB) and Direct Energy Deposition (DED), given their
widespread industrial applications. Patents were categorized into three groups: materials, processes,
and components. Furthermore, AM technologies were analyzed according to their role within the
production cycle: materials preparation, pre-processing, manufacturing, and post-processing. This
categorization allows for a detailed understanding of how innovations in AM contribute to more
sustainable production and consumption practices by improving energy efficiency, material usage,
circularity, and overall environmental impact
Business Models and Advanced Additive Manufacturing strategies for better sustainability
No full textThis article explores the impact of Additive Manufacturing (AM) on business models in the context of
manufacturing sustainability. We define two new standards of sustainable business models enabled by AM and
discuss their potential advantages in addressing specific manufacturing challenges. The technological advancements
brought about by AM have significantly influenced the manufacturing industry, fostering innovation and
reshaping market structures and value-creation processes. Notably, AM contributes to sustainability by reducing
material waste and transportation costs, establishing itself as a low-impact manufacturing technology. While AM
is not positioned to entirely replace traditional manufacturing processes, organizations can leverage its integration
with these processes to catalyze business model innovation. To expand the market for AM technologies, it
is crucial to examine AM not only from a process and technology perspective but also in terms of its ability to
eliminate the need for tooling and dies, which are typically produced through energy-intensive methods.
Advanced manufacturing techniques can significantly reduce greenhouse gas emissions, pollution, and time to
market, demonstrating AM’s potential energy-saving benefits across various sectors
In-Process Detection of Defects on Parts Produced by Laser Metal Deposition Using Off-Axis Optical Monitoring
No full textLaser Metal Deposition (LMD) is emerging among metal Additive Manufacturing technologies due to its wide range of applications. This technique represents an evolution of laser cladding, currently used for fabricating and repairing complex metal components, promoting manufacturing sustainability. One of the main drawbacks hindering the widespread use of these technology is the complexity of implementing monitoring equipment on industrial LMD systems with limited modification setups. Therefore, it is essential to develop appropriate off-axis systems that allow effective monitoring of the deposition process. The present work proposes a prototype off-axis monitoring system consisting of a pair of specially set cameras capable of analyzing the evolution of the melt pool and discerning fundamental information on geometry, size and brightness intensity. By correlating this information with the process outcome, it could be possible to forecast the most frequent defects related to the deposition process. Experimental tests have been carried out, in which powder flow and laser alterations were specifically induced. The prototype system enabled the characterization of each type of process variation and the determination of specific indicators, serving as the basis for achieving a zero-waste sustainable manufacturing process
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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