DIMM-Artículos
URI permanente para esta colecciónhttps://hdl.handle.net/10953/243
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Examinando DIMM-Artículos por Materia "3D printing"
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Ítem Environmental Criteria for Assessing the Competitiveness of Public Tenders with the Replacement of Large-Scale LEDs in the Outdoor Lighting of Cities as a Key Element for Sustainable Development: Case Study Applied with PROMETHEE Methodology(MDPI, 2019-10-28) Hermoso-Orzaez, Jesús; Lozano-Miralles, Adolfo; López-García, Rafael; Brito, PauloThe technological change to LEDs is an unstoppable reality which, little by little, is becoming increasingly important in terms of the lighting inside and outside our homes. The exterior lighting of our cities is moving decisively and clearly towards the incorporation of this technology in urban spaces. The energy efficiency, light quality, and economic benefits of LED technology are an unquestionable reality. This is causing public administration projects involving large-scale switches to LEDs to be promoted and financed; however, it is beginning to be observed that the commitment to the policies decided by this technology should take into account some environmental aspects which have not been studied to date. The environmental impact of the substitutions is caused by the need to valorize the replaced luminaires. Until now, most have been stored without the possibility of use, reuse, or recovery. The environmental impact produced in the manufacture of LED luminaires that replace the old sodium vapor (VSAP) or metal halide (MH) discharge lamps must also be considered. In addition, in the administrative clauses specifications that govern the public tenders, it is observed that the fundamental environmental aspects both of recycling the old lamps, and of the life cycle analysis (LCA) of the luminaires that are replacing them, have not been contemplated or valued with sufficient weight. In addition, there are very few public substitution contests in which environmental criteria are rewarded or valued in an important way. This work intends to summarize a methodological proposal using the techniques of multiple decision-making criteria for the selection of bidding companies for public outdoor lighting competitions. We propose the use of the PROMETHEE method multi-criteria analysis for the application of the most commonly used criteria for the luminaire LED selection process, including an environmental impact assessment with LCA techniques, and propose this as a case or model guide in the public contests of cities. A model of the bidding conditions that addresses and assesses the environmental aspects which are absolutely key to sustainable development is supported by the ecological criteria of the circular economy.Ítem Facing the challenges of the food industry: Might additive manufacturing be the answer?(SAGE, 2019-06) Sartal, Antonio; Carou, Diego; Dorado Vicente, Rubén; Mandayo, LorenzoOur research explores how additive manufacturing can support the food industry in facing its current global challenges. Although information technologies are usually highlighted as the main driver of the Industry 4.0 concept, which was first introduced during the Hannover Fair event in 2011, we posit that additive manufacturing can be the true generator of a sustainable competitive advantage in this sector. This evidence stems from a case study in a plant of one of the world’s largest fishing multinational companies. Our results show how, through robotic claw optimization using three dimensional printing, we not only reduce the manufacturing costs but also increase the flexibility of the line and reduce time to market. On the one hand, our findings should encourage managers to test this technology at their facilities; on the other hand, policymakers should promote the adoption of additive manufacturing, highlighting the potential of this technology within the Industry 4.0 context.Ítem Procedure to Improve the Surface Fidelity of Additive Manufactured Parts via Direct Slicing Tessellation(Elsevier, 2024-05-15) Robles Lorite, Laura; Dorado Vicente, Rubén; García Collado, Alberto; Torres Jiménez, EloísaPart appearance issues due to dimensional and shape inaccuracies (fidelity) hinder the use of additive manufacturing processes to obtain final products. Inaccuracies come from process parameter definition, post-processing operations, and the slicing process. Regarding the slicing procedure, the conventional approach is the indirect slicing of a tessellation that approximates the part model. Layer computation is straightforward in this method but introduces dimensional deviations for curvilinear surfaces. Direct slicing minimizes these deviations, but computation and layer representation are complex. This work blends both solutions, explaining how to build an improved tessellation from direct slices that can be introduced and processed in usual slicing programs. Two shapes , a simple hemisphere and a component of a retail product (a hair dryer nozzle), were printed by Fused Filament Fabrication (FFF), using conventional indirect slicing with different tessellation’s resolutions and the proposed Direct Slicing Tessellation (DST). The resulting samples were measured using a 3D scanner. Compared with a reference sample printed from a Computer-Aided Design (CAD) model discretized with a tolerance < 6 um, maximum deviations were found on more areas of conventional indirect samples and with higher values (from 0.13 to 0.16 mm) than in the case of the DST samples (with maximum deviation of 0.1 mm at few points on the surface). Additionally, DST files are around ten times smaller than reference files. Finally, the deviation between the CAD model and the representation on the resulting surfaces of zebra stripes and mean curvature show that the proposed solution enhances the printed surface fidelity compared to the conventional indirect slicing.