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The purpose of this paper is to analyze the aerodynamic improvements obtained in a wing section with a NACA 0018 airfoil manufactured using the fused deposition modeling (FDM) technique with regard to a smooth surface made by milling. The creation of micro-riblets on the surface of the airfoil, due to the deposition of the material layer by layer, improves the general aerodynamic performance of the parts, provided that the riblets are parallel to the flow line. The incidence of the thickness of the thread deposited in each layer – to be the variable on which the geometry of the riblets is based – was studied.

The wing section was designed using 3D software. Three different models were designed by rapid prototyping, using additive and subtractive manufacturing. Two of the profiles were manufactured using FDM varying the thickness of the layer to be able to compare the aerodynamic improvements. The third model was manufactured using a subtractive rapid prototyping machine generating a smooth surface profile. These three models were tested inside the wind tunnel to be able to quantify the aerodynamic efficiency according to the geometry and the riblets size.

The manufacture of an aerodynamic profile using FDM provides, in addition to the lightness and the ability to design parts with complex geometries, an improvement in the aerodynamic efficiency of 10 per cent compared with profiles with a smooth surface.

With the aerodynamic advantage gained through the use of FDM positions, the additive manufacturing serves as an excellent alternative for the manufacture of lightweight aerodynamic parts, with low structural loading and with low Reynolds number (∼5·105). This technological advantage would be applied to the UAV (unmanned aerial vehicle) industry.

The study carried out in this article demonstrates that the use of FDM as a manufacture process of end-used parts that are subject to movement generates an additional advantage that had not been considered. The additive manufacturing allows us to directly manufacture riblets by creating the necessary surface so as to reduce the aerodynamic drag.

The purpose of this paper is to characterize a new structural bi-material (scaffold and filler).

The bi-material has been obtained by means of an additive manufacturing system consisting of a fused filament fabrication extruder head and an epoxy resin depositor head. The new bi-material will consist of a thermoplastic material that will serve as the main structure and an epoxy resin that will serve as a filler and adhesion between layers. The creation of this new bi-material will improve the physical–chemical and mechanical properties with respect to the thermoplastic material. This paper will focus on the impact behavior of IZOD and the impact behavior of punctures.

The new polylactic acid (PLA) and epoxy bi-material allow improvements in toughness and puncture impact resistance compared to the PLA thermoplastic. This increase in toughness is between 20% and 30% depending on the orientation of the print. In the same way, the energy absorbed in the puncture impact test has been increased by 42%–48%.

The improvement in the impact absorption capacity of this new bi-material makes it ideal for the manufacture of medical parts in which customization, lightness and impact resistance are their main characteristics such as sports protection systems.

The originality of creating parts through additive manufacturing that combines a material generated with cold extrusion, such as epoxy resin and a material generated with hot extrusion, such as thermoplastics, lies in the unique synergy that this mixed and simultaneous technique offers. By uniting these two manufacturing methods, it allows the exploration of new physical and chemical properties in the resulting parts, taking advantage of the individual advantages of each material. This combination opens the door to the creation of components with a wider range of characteristics, from strength and durability to flexibility and temperature resistance, thus offering innovative and versatile solutions for various applications in fields such as engineering, medicine and design.

The objective of the research is to evaluate the carbon footprint of the green asparagus (Asparagus officinalis L.) supply chain, encompassing the agricultural production to the packaging stage in Italy, as it is the sixth largest producer and the second largest in Europe. It provides an assessment in the province of Foggia and highlights the global perspective of the carbon footprint application in agro-food systems.

The carbon footprint (ISO 14067:2018) considers 1 t of packaged fresh asparagus as a functional unit in the agricultural production and packaging stage and is based on primary data collected in one of the leading companies of asparagus production in the province of Foggia, which markets about 0.21 kt of asparagus per year produced in about 31 ha. Data were integrated with face-to-face in-depth interviews and pre-filled checklists.

Findings show that the carbon footprint of 1 t of packaged fresh asparagus is equivalent to 335.31 kgCO2eq, of which 61% in the agricultural stage and 39% in the packaging one. The majority of the emissions are associated with the fertigation and the diesel consumption for the transportation of workers. Farmers should adopt green electricity so as to reduce the emissions associated with the electric pump for the extraction of water from artesian wells. Moreover, it would be desirable to replace mineral urea phosphate with organic fertilizers.

To the best of the authors’ knowledge, scholars have not yet investigated the environmental impacts of the green asparagus supply chain, even if it represents one of the most cultivated vegetables worldwide, with a global production that amounts to 8.5 Mt per year.

The purpose of this paper is to describe how an academic library at one of the most diverse universities in the country responded to the 2016 election through the newly formed Inclusion and Equity Committee and through student outreach.

This paper details the context of the 2016 election and the role of social justice in librarianship. It offers ideas for how library diversity committees can address professional development, recruitment and retention efforts and cultural humility. It highlights student outreach efforts to support marginalized students, educate communities and promote student activism. Finally, it offers considerations and suggestions for librarians who want to engage in this work.

This paper shows that incorporating social justice, diversity, equity and inclusion requires individuals taking action. If institutions want to focus on any of these issues, they need to formally include them in their mission, vision and values as well as in department goals and individual job descriptions. The University of Nevada, Las Vegas University Libraries fully supports this work, but most of the labor is done by a small number of people. Unsustainable practices can cause employee burnout and turnover resulting in less internal and external efforts to support diversity.

Most of the previous literature focuses either on internal activities, such as professional development and committees, or on student-focused activities, such as outreach events, displays and instruction. This paper is one comprehensive review of both kinds of activities.

Whilst the real estate development appraisal practices of large national and international real estate companies are well understood, relatively little is known about how development appraisals are conducted by indigenous appraisers and valuers in developing countries. The purpose of this paper is to investigate how development appraisal is conducted in Brazil, compared to the UK, focusing primarily on the methods employed by small- and medium-sized real estate practices and their appraisers to appraise the viability of commercial real estate developments in the State of Sao Paulo.

The study employs a two phase Delphi Method to capture and analyse empirical data from small- and medium-sized real estate appraisers in Brazil. Using the long established and relatively transparent UK Residual Method of development appraisal as a template against which to compare Brazilian appraisal methods, guidance and practice. To understand how indigenous development appraisers operate the Brazilian development appraisal methods, the research was conducted in Portuguese by a bi-lingual real estate expert who was familiar with both UK and Brazilian practice.

The research establishes that appraisers working for small- and medium -sized real estate practices in Brazil rarely use the Residual Method. Instead, they employ a range of methods, the choice of which is heavily influenced by the availability of comparable market data, with Direct Comparison of market data and the Capitalisation of Income being the methods of choice. Appraisers rarely employ the Residual Method as the principal development appraisal technique, using instead the Comparative Method and Discounted Cash Flow (DCF) analysis. Land prices are usually agreed or already known and developer’s profit is usually determined using DCF analysis and is highly sensitive to fluctuations in construction costs.

The research engaged with a small number of appraisers and valuers in small- and medium-sized practices in the State of Sao Paulo using a two-phase Delphi Method. The long established UK Residual Method of development appraisal was used as a template against which to compare practice in Sao Paulo State. There is potential therefore to replicate the research in other Brazilian States and transfer the methodology to other developing countries.

In Brazil, when development land in urban areas is acquired on the basis of plot exchange, land is often sold at less than market value and the original landowner retains an equity stake in the development and shares in the development overage. The practice of “permuta física”, giving landowners the freehold of part of the development, or “permuta financeira”, whereby the landowner receives an enhanced land price, indexed against development value, is of potential relevance to the UK and other developed countries that need help in urban unlocking land markets.

The research is a unique comparative study of development appraisal methods employed by small- and medium-sized practices in Brazil. It contributes to the limited literature that has so far been published in English on Brazilian development appraisal methods and reveals the similarities and differences with the Residual Method of development appraisal that is widely used in the UK and other developed countries.

This paper aims to provide information about the structure of collaborative work among Argentinian economics. The study provides specific applied research of social network analysis focus on this profession in this specific country.

The contribution opted for applying social network analysis tools to papers presented in a congress and published in its proceedings. The authors focus in detecting main actors, groups of co-authorship, professionals acting as bridges between groups and differences between genders.

The paper provides empirical insights about how co-authorship has evolved between Argentine economists. The authors find that structural properties of the network, main actors, both male and female, main universities or center that affiliates them, a gender gap that might be closing out.

The paper focuses on the network for the period 1964-2014 without a more detailed dynamic. It also does not explain main topics worked by the authors.

The work provides knowledge about how groups are created in Economics in Argentina, how cooperation has evolved and what has been the role of women in this development. It also shows how different departments and entities collaborate with diverse success in the creation of new knowledge in Economics in Argentina.

The paper works with data from a source of information non-previously studied and contributes in explaining a particular type of collaborative work in a profession in Argentina.