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This paper aims to investigate the quality of printed surfaces and manufacturing tolerances by comparing the cylindrical cavities machined in parts obtained by fused deposition modeling (FDM) with the holes manufactured during the printing process itself. The comparison focuses on the results of roughness and tolerances, intending to obtain practical references when making assemblies.

The experimental approach focuses on the comparison of the results of roughness and tolerances of two manufacturing strategies: geometric volumes with a through-hole and the through-hole machined in volumes that were initially printed without the hole. Throughout the study, both alternates are explained to make appropriate recommendations.

The study shows the best combinations of technological parameters, both machining and three-dimensional printing, which have been decisive for obtaining successful results. These conclusive results allow enunciating recommendations for use in the industrial environment.

This paper fulfills an identified need to study the dimensional accuracy of the geometries obtained by additive manufacturing, as no experimental evidence has been found of studies that directly address the problem of the FDM-printed part with geometric and dimensional tolerances and desirable surface quality for assembly.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.

The aim of this study is to provide insights into how the purchasing function can increase the maturity of smart maintenance management (SMM) in construction clients by (1) assessing current SMM maturity and (2) developing an adapted service triad for purchasing's meaningful involvement in SMM.

A multiple case research design was used, and data were collected from four higher education institutes in the Netherlands through an assessment of their current SMM maturity. Coding and a cross-case analysis were used to qualitatively analyze the data to identify roles and value chain integration factors as intermediate steps in adapting the service triad to a service hexad.

Within construction client organizations, collaboration between maintenance management, project management and ICT services requires improvement. The proposed service hexad redefines the client's SMM roles with the aim of improving collaboration. The authors discuss how this enables a transition to higher levels of SMM maturity.

The findings were derived from a particular class of construction clients: higher education institutes that operate owner-occupied properties. Although the service hexad could be adapted, to owner-occupied multi-user properties, further research is necessary to assess its relevance for investor-owned properties.

Implementing the service hexad provides construction clients with a stronger position in supply networks. It clarifies the briefing process in construction management and emphasizes the data supply responsibilities of construction management professionals.

The study draws on the service triads and meaningful involvement concepts from the purchasing literature and applies them to SMM.

The purpose of this research is to study the Colombian avocado export industry, identify key insights associated with creating and sustaining the avocado value chain, and to understand the impact of the public policies affecting this industry.

The approach consists of two case studies to shed light on the opportunities and challenges of developing a sustainable avocado value chain in Colombia. One case deals with a vertically integrated business (Arcángel Miguel) while the other focuses on an association of small growers (Asohass). The analysis was informed by a series of interviews with key actors along the avocado supply chain to uncover the business strategies to move avocados to destination markets. The authors compare and contrast approaches to business development, international expansion, and role of public policies.

The authors found that the strategies followed by these organizations differ in means but aim for the same objective: maximize profits, improve environmental performance, and enhance the social wellbeing of growers. The authors found that each type of business model requires distinct public policies to succeed and different strategies to appropriately allocate efforts. The findings are relevant to other high-value crops and other Latin American countries with similar geographical and social characteristics.

These insights underscore the need of public policies tailored to the specific needs of the different actors in the value chain. The current emphasis on certifications and export markets works well for large agribusinesses, but smallholder growers need policies tailored to new investments in physical, human, and social capital.

This study contributes to the literature on avocado value chains in Latin America, emphasizing the challenges faced by the emergent Colombia avocado sector, a country that only began exporting this commodity in 2010.

The Covid-19 pandemic has rekindled interest in sovereign debt crises amidst calls for debt relief for developing and emerging countries. But has debt relief lessened the debt burdens of emerging and developing economies? The purpose of this paper is to empirically address this question. In particular, the focus is on the implications of debt relief and institutional qualities for sovereign debt in emerging and developing economies.

The model extends the framework on the probability of default by incorporating the receipt of debt relief by a debtor country. Doing so allows to better explain movements of sovereign defaults relating to debt relief. The model is estimated via the regular probit regression.

The analysis shows that the debt relief provided, thus, far, failed to ease the debt overhang problems of developing and emerging countries and reduced investment. The current debt relief schemes may underscore the prospects of self-enforcing and self-fulfilling sovereign debt crises rather than eliminating the dilemma completely. Regarding the forms of debt relief, the analysis shows that debt forgiveness offers favourable prospects in terms of debt sustainability and economic outcomes than debt rescheduling. Perhaps, the sovereign debt crises, particularly in low-income countries, hinge on insolvency problems rather than transitory illiquidity issues.

Any debt relief mechanism should consider seriously the potential incentive effect that reinforces expectations of future debt-relief initiatives. Importantly, solving the sovereign debt problem requires a programme for sustained investment and economic growth, while not discounting the critical role of prudent debt management policies and institutions.

This study contributes a different angle to the debate on sovereign debt distress. Aside from the structural and economic factors, this study investigates the role of debt management policy in the debtor nation and the implications of debt relief benefits for sovereign risk. The framework also focuses on whether the different forms of debt relief exert distinctive impacts.

This research aims to contribute to History of Education Studies as well as to New Cold War Studies, by examining a Reactor Technology Specialist Engineer program, launched in Hungary three times in the 1980s for Cuban nuclear engineers, graduates of the University of Havana.

The institutional setting, the content of the program, the teaching staff, the students, and the outcomes are studied. The factors that motivated the birth of this special program are examined, including the following areas; in what ways it was different from the courses in which foreign students participated in Hungary; what its strengths and weaknesses were; how we can learn from this past experience and what relevance it has for the present.

The analysis – carried out within the context of Cuban–Hungarian relations in the Cold War – demonstrates that these two satellite countries used the fields of science and education to widen their international possibilities and at the same time to reinforce their national interests by cooperating with each other.

The investigation is based on archival sources, university yearbooks and journals as well as contemporary Hungarian press. Written sources were complemented by interviews with Cuban students and Hungarian teaching staff, thus providing a personal perspective, balancing official views.