103,387 research outputs found
Estudo comparativo entre as técnicas de nissen e Boix-Ochoa em ratos
OBJETIVO: Comparar, em ratos, a eficiência das técnicas de Nissen e Boix-Ochoa no tratamento do refluxo gastroesofagiano (RGE) induzido pela operação de Heller. MÉTODO: Foram usados 30 ratos Wistar, com idades entre 40 e 60 dias de vida e peso corporal entre 210 g e 342 g. Os animais foram distribuídos em três Grupos (A, B, C) de 10 ratos. Em todos os animais realizou-se a operação de Heller. No Grupo B ela foi seguida de uma operação de Nissen e, no Grupo C, de uma operação de Boix-Ochoa. A pressão intra-gástrica necessária para produzir RGE foi medida em todos os animais: antes de qualquer procedimento; imediatamente após as operações de Heller, Nissen e Boix-Ochoa; e seis semanas depois, quando os animais foram mortos. RESULTADOS: Verificou-se que tanto a recuperação da perda de peso, que caracteriza o quadro de RGE, como a reconstituição mais fisiológica dos gradientes pressóricos gastroesofagianos são obtidos de forma mais eficiente pela técnica de Boix- Ochoa. CONCLUSÃO: As operações de Nissen e Boix- Ochoa são eficientes no tratamento do RGE induzido pela técnica de Heller, em ratos. A segunda, no entanto, restaurou, de forma mais adequada, os valores fisiológicos dos parâmetros estudados neste trabalho: o peso corporal e os gradientes pressóricos gastroesofagianos
Design for manufacturing and assembly methods in the product development process of mechanical products: a systematic literature review
The design for manufacturing and assembly (DFMA) is a family of methods belonging to the design for X (DfX) category which goal is to optimize the manufacturing and assembly phase of products. DFMA methods have been developed at the beginning of the 1980s and widely used in both academia and industries since then. However, to the best of the authors’ knowledge, no systematic literature reviews or mapping has been proposed yet in the field of mechanical design. The goal of this paper is to provide a systematic review of DFMA methods applied to mechanical and electro-mechanical products with the aim to collect, analyse, and summarize the knowledge acquired until today and identify future research areas. The paper provides an overview of the DFMA topic in the last four decades (i.e., from 1980 to 2021) emphasizing operational perspectives such as the design phase in which methods are used, the type of products analysed, the adoption of quantitative or qualitative metrics, the tool adopted for the assessment, and the technologies involved. As a result, the paper addresses several aspects associated with the DFMA and different outcomes retrieved by the literature review have been highlighted. The first one concerns the fact that most of the DFMA methods have been used to analyse simple products made of few components (i.e., easy to manage with a short lead-time). Another important result is the lack of valuable DFMA methods applicable at early design phases (i.e., conceptual design) when information is not detailed and presents more qualitative than quantitative data. Both results lead to the evidence that the definition of a general DFMA method and metric adaptable for every type of product and/or design phase is a challenging goal that presents several issues. Finally, a bibliographic map was developed as a suitable tool to visualize results and identify future research trends on this topic. From the bibliometric analysis, it has been shown that the overall interest in DFMA methodologies decreased in the last decade
Intervenció d'Oriol Boix a la inauguració dels nous espais del Departament d'Enginyeria Elèctrica a ETSEIB
Pla general d'Oriol Boix durant la seva intervenció a la inauguració de les noves instal·lacions del Departament d'Enginyeria Elèctrica, situades al Pavelló G de l'Escola Tècnica Superior d'Enginyeria Industrial de Barcelona. A la imatge: Oriol Boix Aragonès (sotsdirector d'equipaments i gestió econòmica de l 'ETSEIB i membre del Departament d'Enginyeria Elèctrica de la UPC), Jordi Ros Ballesteros (vicerector d'Arquitectura, Infraestructures i Territori de la UPC), Enric Fossas Colet (director de l'ETSEIB) i Samuel Galceran Arellano (director del Departament d'Enginyeria Elèctrica de la UPC i professor d'aquest mateix departament
Intervenció d'Oriol Boix a la inauguració dels nous espais del Departament d'Enginyeria Elèctrica a ETSEIB
Pla general d'Oriol Boix durant la seva intervenció a la inauguració de les noves instal·lacions del Departament d'Enginyeria Elèctrica, situades al Pavelló G de l'Escola Tècnica Superior d'Enginyeria Industrial de Barcelona. A la imatge: Oriol Boix Aragonès (sotsdirector d'equipaments i gestió econòmica de l 'ETSEIB i membre del Departament d'Enginyeria Elèctrica de la UPC), Jordi Ros Ballesteros (vicerector d'Arquitectura, Infraestructures i Territori de la UPC), Enric Fossas Colet (director de l'ETSEIB) i Samuel Galceran Arellano (director del Departament d'Enginyeria Elèctrica de la UPC i professor d'aquest mateix departament
Industrial districts, innovation and I-district effect: territory or industrial specialization?
The I-district effect hypothesis establishes the existence of highly intense innovation in Marshallian industrial districts due to the presence of external localization economies. However, industrial districts are characterized by specific manufacturing specializations in such a way that this effect could be due to these dominant specializations. The objective of this research is to test whether the effect is explained by the conditions of the territory or by the industrial specialization and to provide additional evidence of the existence and causes of the highly intense innovation in industrial districts (I-district effect). The estimates for Spain of a fixed effects model interacting territory and industry suggest that the high innovative performance of industrial districts is maintained across sectors whereas the industrial specialization behaves differently depending on the type of local production system in which it is placed. The I-district effect is related to the conditions of the territory more than to the industrial specialization. The territory is a key variable in explaining the processes of innovation and should be considered a basic dimension in the design of innovation and industrial policies.industrial districts, innovation, external economies, district effect
Recovered phosphorus for a more resilient urban agriculture: Assessment of the fertilizer potential of struvite in hydroponics
Urban agriculture (UA) is a means for cities to become more resilient in terms of food sovereignty while shortening the distance between production and consumption. However, intensive soilless UA still depends on the use of fertilizers, which relies on depleting non-renewable resources such as phosphorous (P) and causes both local and global impact for its production and application. With the aim to reduce such impacts and encourage a more efficient use of nutrients, this study assesses the feasibility of using struvite precipitated from an urban wastewater treatment plant as the unique source of P fertilizer. To do so, we apply various quantities of struvite (ranging from 1 to 20 g/plant) to the substrate of a hydroponic Phaseolus vulgaris crop and determine the yield, water flows and P balances. The results show that treatments with more than 5 g of struvite per plant produced a higher yield (maximum of 181.41 g/plant) than the control (134.6 g/plant) with mineral fertilizer (KPO4H2). On the other hand, P concentration in all plant organs was always lower when using struvite than when using chemical fertilizer. Finally, the fact that different amounts of struvite remained undissolved in all treatments denotes the importance to balance between a correct P supply to the plant and a decrease of P lost through the leachates, based on the amount of struvite and the irrigated water. The findings of this study show that it is feasible for UA to efficiently use locally recovered nutrients such as P to produce local food
Do creative industries cluster? Mapping Creative Local Production Systems in Italy
An important debate on the role of creativity and culture as factors of local economic development is distinctly emerging. Despite the emphasis put on the theoretical definition of these concepts, it is necessary to strengthen comparative research for the identification and analysis of the kind of creativity embedded in the territory as well as its determinants. Creative local production systems are identified in Italy and Spain departing from local labour markets as territorial units, and focusing on two different kinds of creative industries: traditional cultural industries (publishing, music, architecture and engineering, performing arts) and technology-related creative industries (R&D, ICT, advertising). The results suggest the existence of different patterns of concentration of creative industries in both countries and the concentration of creative industries in thecreative industries, creative local systems, agglomeration economies
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
Dieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
We 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
Eco-design actions to improve life cycle environmental performance of face masks in the pandemic era
Face masks are currently considered essential devices that people must wear today and in the near future, until the COVID-19 pandemic will be completely defeated through specific medicines and vaccines. Such devices are generally made of thermoplastic polymers, as polypropylene and polyethylene and are single use products. Even if in this period the sanitary emergency must have the maximum priority, the world society should not completely forget the environmental problem that are causing more and more obvious climate changes with correlated damages to ecosystems and human health. Despite the well-known correlation among anti-COVID protective equipment (or more generally medical devices) and environmental issues, the Life Cycle Assessment (LCA) and eco-design-based studies in this field is very scarce. The present study aims to derive the most important environmental criticalities of such products, by using LCA and product circularity indicators of five different common masks. The final aim is to provide eco-design guidelines, useful to design new face masks by preventing negative impact on the environment
- …
