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- Information systems driven to decision support and institutions’ success in the higher education contextPublication . Pinho, Cláudia Sofia Borges; Franco, Mário José Baptista; Mendes, Luís António FonsecaThe main aim of this Ph.D. thesis in Management is to provide better understanding of the role of Information Systems (ISs) in the decision-making process and successful performance of Higher Education Institutions (HEIs), exploring the antecedents of technology acceptance. To achieve the objectives defined, four articles were elaborated: a Systematic Literature Review (SLR) and three articles of an empirical nature. Therefore, the first article aimed to identify, explore and systematize the main topics regarding the role of web portals as tools to support information management in HEIs. Based on 126 articles published up to 5 November 2016 on the Web of Science and SCOPUS databases, four major topics were identified, namely, the software used in web portals, internal and external benefits of using web portals, technology acceptance and information storage and management. The main contribution of this research lies in identifying the main topics and trends in scientific production for each topic identified, and in identifying gaps and future lines of research in this field of study. The second article aimed to study the influence of web portals in supporting HEI management and performance, considering personality traits, perceived usefulness and perceived ease of use, through an empirical study. To achieve the aim proposed, Structural Equation Modelling (SEM) was used together with a structured questionnaire administered to teaching and non-teaching staff in Portuguese HEIs. The results obtained, through 338 valid responses, indicate a positive influence of personality traits on the use of web portals and that their use also has a positive influence on HEIs’ performance. The third chapter sought to identify the factors influencing the use of e-learning platforms in the Portuguese academic context through an empirical study. A structured questionnaire was used to collect information. Based on 631 valid responses, SEM was applied, leading to the conclusion that, in accordance with Innovation Diffusion Theory (IDT), the characteristics of e-learning platforms and Personal Innovativeness in Information Technology (PIIT) have a positive influence on the use of this tool. The fourth and final article aimed to identify and explain the factors of successful operation, implementation and use of e-libraries in the academic context of Portuguese higher education. To achieve this goal, a qualitative approach was adopted, through a case study of the e-library at the University of Beira Interior (UBI). Primary data were obtained from interviews with staff of the library, computer services and administration of this teaching institution holding leadership positions and directly involved in the implementation, maintenance or use of the e-library. The empirical evidence highlights the importance of minimizing costs, particularly by forming cooperation protocols, the use of open-source software and training of UBI library staff. Acceptance and use of the e-library depends on the platform’s characteristics, the ease of access to information, actions to publicise and make the whole academic community aware of the e-library and its functions, and implementation of appealing, intuitive User Interfaces (UIs). In addition, the training of students and library staff was revealed as a relevant factor for acceptance of this tool. For the future, the creation of a functional search aggregator is suggested, to allow a simultaneous search in all the databases and creating the least noise possible. This function could be implemented based on multi-disciplinary teams with skills acquired through specific training. This study was based on Resource-Based View (RBV) and Social Learning Theory (SLT). In this thesis, considering the four studies developed, it was possible to support the influence of IS acceptance on HEIs’ performance and determine the role of ISs in supporting these institutions’ management, in the Portuguese academic context. This research also presents contributions to theory and implications for practice, as well as future lines of study on the topic.
- In situ green reduced graphene oxide functionalized 3D printed scaffolds for bone tissue regenerationPublication . Cabral, C.S.D.; Miguel, Sónia; Diogo, Duarte Miguel De Melo; Louro, Ricardo; Correia, IlidioThe incorporation of reduced graphene oxide (rGO) nanomaterials into scaffolds structure can be explored to enhance the properties of these 3D matrices in bone regeneration applications. However, the weak water solubility and poor colloidal stability of rGO have hindered its incorporation in blends aimed to produce scaffolds by 3D printing. Furthermore, rGO is generally obtained by treating graphene oxide (GO) with hydrazine hydrate, which is a highly hazardous reducing agent. To overcome these problems, herein a novel environmentally-friendly method was developed to assemble 3D printed scaffolds incorporating rGO. Such was achieved through the in situ reduction mediated by l-Ascorbic acid of the GO already present on tricalcium phosphate/gelatin/chitosan scaffolds. The scaffolds functionalized with rGO through the in situ method (TGC_irGO) displayed enhanced wettability and improved mechanical properties without impairing their porosity when compared to their equivalents functionalized with GO and non-functionalized scaffolds (TGC_GO and TGC, respectively). Moreover, the TGC_irGO scaffolds displayed an improved calcium deposition at their surface and an enhanced alkaline phosphatase (ALP) activity, along 21 days of incubation. Additionally, scaffolds also displayed antimicrobial activity without compromising osteoblasts’ viability and proliferation. Such features reveal the potential of the TGC_irGO scaffolds for bone tissue regeneration applications.
- Valores globais ou locais? O Caso do Conferp na Defesa de uma Conduta Profissional Ética no BrasilPublication . Gonçalves, Gisela; Pereira, Nathalia; Toniolo, BiancaNeste artigo, optamos por discutir o tema da ética a partir da perspectiva das associações e dos conselhos profissionais. Partindo de uma breve análise da evolução e da regulamentação da profissão no Brasil, direcionamos a nossa atenção para o Sistema Conferp e para o seu papel na defesa de uma prática ética das RP. Para melhor compreender este papel, analisamos o seu posicionamento normativo à luz do Global Principles of Ethics da Global Alliance. Com a nossa pesquisa identificamos que os 16 princípios globais da GA se encontram refletidos e, em larga medida, no código de ética do Conferp, e que ele desempenha um papel ativista. Palavras-chave Ética; Relações Públicas; Global Alliance; Conferp; Brasil. Introdução Quer no âmbito profissional quer acadêmico, a ética tem ocupado um lugar central no debate sobre o que são as relações públicas, o que fazem e como devem ser praticadas na contemporaneidade. Várias razões se poderiam apontar para esta indagação normativa, algumas históricas outras contextuais. As razões históricas prendem-se, entre outras, com a origem difusa da profissão, muito próxima da propaganda e da publicidade; com a relação contenciosa com a esfera jornalística e; com a conotação com manipulação, ou spin, da informação e da opinião pública. As razões contextuais decorrem da atual "implosão da confiança" (EDELMAN, 2017) dos cidadãos nas instituições, governos e organizações e de um contexto midiático altamente fragilizado por fenômenos como as "fake news" ou os "social bots".
- Networks and measuring the performance in current creative citiesPublication . Rodrigues, Margarida Maria Mendes; Franco, Mário José BaptistaThe phenomenon of globalization and the need to combat the harmful effects of the recent financial and economic crisis associated with rapid urban development and stagnant economic growth in countries/regions/cities seen in the last decade worldwide, has led to a paradigmatic change in the view of cities’ role in urban economic development. This profound change means that cites are faced with a complex and enormous challenge, set out in the European Union’s 2020 Strategy based on the premises of long-term intelligent, inclusive and sustainable economic growth. However, these premises imply that models of economic growth and their traditional determining factors are altered, and so development of the so-called new economy is in evidence. This means that the new economy proposed by the European Union, besides being based on traditional factors generating economic growth, has come to include a new own resource, the intangibility and soft and hard amenities of urban places, or cities, as factors associated with cities’ urban economic development. The changes in regional and public policies linked to repositioning cities have aroused great interest in the academic world and in other public and private agencies, leading to the emergence of countless constructs, concepts and models aiming to contribute to understanding of this global phenomenon. In this context, the concepts of creativity, intelligence and urban sustainability, as inseparable dimensions of cities, have gained relevance in studies on cities, particularly regarding their measurement. Consequently, a series of models and indices have been developed aiming to answer the question of how to assess cities’ performance around these dimensions. This proliferation of studies has not exhausted the topic, as gaps remain to be filled, particularly those involving great complexity by interlinking various constructs such as urban networks, besides creativity, intelligence and urban sustainability in cities. In this scenario, the general aim of the research presented here is to propose a holistic, multidimensional model for Current Creative Cities (CCCs) and its empirical validation through constructing a Composite Index for their holistic performance. The broad spectrum of this objective is clear, and so it was divided in six specific objectives, namely: 1) to map the most studied topics concerning networks and the performance of creative cities, through a bibliometric analysis; 2) to present a proposal of a multidimensional design for CCCs and the respective indicators to measure their performance; 3) to validate empirically the model proposed for each dimension proposed per se, and subsequently, for all the dimensions of the holistic model as a whole; 4) to demonstrate that networks are predictors of CCCs’ holistic performance; 5) to propose a taxonomy for the holistic performance of CCCs and 6) to analyse the effect of living labs on the economic growth of CCCs. 5) to propose a taxonomy for the holistic performance of CCCs; To respond to these aims a mixed research methodology was adopted, since quantitative and qualitative approaches complement each other, particularly concerning internal and external validity, using different research techniques of a deductive and inductive nature, as explained below. In Chapter 2, responding to the first objective, the bibliometrics revealed the most studied topics, besides exponential interest in studying creative cities and networks together. It was also clarified that creativity can be associated with intelligence and urban sustainability in CCCs, that there is still a need to construct a holistic, transversal model for these dimensions, and that this should allow measuring performance and the effect of networks on this. The result obtained in this study directed the research to Chapter 3, i.e., to the second aim established, and so a multidimensional, holistic model is presented to measure CCCs’ holistic performance. With the answers to the first objectives defined, Chapters 4, 5, 6 and 7 aim to provide the response to the third and fourth objectives, presenting individual Composite Indices and for the Holistic Performance of CCCs, obtained through multivariate statistical techniques – Exploratory Factor Analysis (EFA) and Principal Components Analysis (PCA). These indices were validated empirically in Portugal. The results obtained and their discussion revealed that strategies directed to implementing creative, intelligent and sustainable measures are visible in economic growth in Portugal, despite the need to continue to develop and spread the structural and conjunctural bases through public policies aiming to overcome persisting weaknesses. Therefore, the methodological tool presented here is a bonus for local authorities and their public policies. The demographical, spatial and territorial variations of Portuguese towns and cities led to developing a taxonomy of their holistic performance, to respond to the fifth objective defined by using Hierarchical Cluster Analysis, presented in Chapter 8. The results show that improved holistic performance is only achieved when taking all the axes/dimensions of CCCs as a synergetic whole and as a cyclical consequence rather than per se. Finally, these results were complemented in Chapter 9 (sixth objective) by the case study method applied to the town of Fundão, which demonstrated it is not enough to activate the means for citizens to be dynamic actors in improved holistic performance, as current public policies must be strategically managed and promoted by reducing the financial costs involved. The studies presented here allowed presentation of a Composite Index for the Holistic Performance of Portuguese towns and cities, which with the due adaptations to the context analysed can be applied generally. This instrument forms the main contribution of this research, which is of an innovative and relevant nature by being based on urban networks as inductors and catalysts of improved urban economic growth in cities/local authorities. It is also shown that when cities include networks in their public policies, the intangible returns obtained benefit their holistic performance indirectly. Finally, Chapter 10 describes the limitations of the studies presented and makes general conclusions and contributions with implications for theory and practice.
- ERASMUS+ staff mobilityPublication . Gabriel, Graça da Conceição FilipeWe live in an age of global knowledge, with rapid advances in science and technology and acceleration in learning. We also live in an age of profound need for more cohesive and inclusive societies which allow citizens to play an active role in democratic life, thus fostering social integration, and enhancing intercultural understanding. It is through education and training that that nowadays societies and individuals can play a decisive role tackling socio-economic changes and other key challenges. The labour market accompanies these changes, requiring professionals to be able to interact in a global setting. Furthermore, some particular skills are increasingly viewed as major soughtafter assets: intercultural skills, global awareness, foreign language(s) expertise, interconnected networking, lifelong learning, tolerance and constant adaptability. The Erasmus+ is the European Union's programme that invests in knowledge, skills and competences that will benefit individuals, organisations and society as a whole by ensuring equity, prosperity and social inclusion. This programme is also an effective instrument for personal fulfilment. The present report aims at providing a summary of the Erasmus+ Staff Mobility Programme developed at The Saint Petersburg State University (SPbU) from 13th May to 17th May 2019. It offers a brief description of the city, the university and the Library, together with an account of the main activities undertaken at the M. Gorky Scientific Library.
- Immunotherapy in Allergic Asthma – 5 year analysis: Is it a curative approach?Publication . Costa, J. Coutinho; Machado, João Neiva; Ferreira, C.; Gama, Jorge; Almeida, T.; Arrobas, A.M.Asthma is a common, chronic and heterogeneous disease;it affects people of all ages and there has been a recentincrease in its prevalence and severity. It may be mild,barely noticed by the patient, or it may range all the way tovery severe disease, causing constant symptoms that greatlyaffect the quality life of the patient. [...]
- Motivações para o voluntariado e satisfação com a vida em estudantes do Ensino SuperiorPublication . Fortunato, Fabiana Inês Formiga; Cunha, Ana Isabel Silva Santos Barbosa; Alves, Marta Sofia Lopes PereiraAs motivações e os determinantes do voluntariado têm sido um tema bastante discutido na literatura, bem como os benefícios decorrentes da sua prática e sua contribuição para o bem-estar e satisfação com a vida. No Ensino Superior, o envolvimento em ações de voluntariado também tem sido estudado, no entanto, as motivações para o voluntariado e sua relação com a satisfação com a vida em estudantes universitários não é evidente. O presente estudo pretende analisar as motivações para o voluntariado em estudantes universitários e a sua relação com a satisfação com a vida. Participaram no estudo 170 estudantes da Universidade da Beira Interior, que praticam ou já praticaram voluntariado, com idades compreendidas entre os 18 e os 24 anos (M=19.49; DP=1.693). Os instrumentos utilizados incluíram a versão portuguesa do Inventário de Motivações para o Voluntariado (IMV; Clary & Snyder, 1998) e da Escala de Satisfação com a Vida (SWLS; Diener et al., 1985). Os resultados revelaram que as motivações de experiência e de valores foram as mais valorizadas pelos participantes. Os estudantes que se encontram a praticar atualmente voluntariado têm maiores níveis de motivação de valores, experiência, crescimento, carreira e social, em comparação com os que não praticam atualmente voluntariado. As motivações de experiência, carreira e social encontram-se associadas a uma maior satisfação com a vida. São discutidas as implicações dos resultados no âmbito da relação entre voluntariado e bem-estar no Ensino Superior.
- Aerodynamic Breakup of a Single Droplet due to a CrossflowPublication . Carrolo, Gabriel Alexandre da Costa; Silva, André Resende Rodrigues daThe present experimental work focuses on the aerodynamic breakup study of unconventional fuels. This process refers to the secondary atomization of a drop due to a cross-flow, where different velocities cause several regimes and structures appear amidst drop deformation of Jet Fuel mixtures with HVO (hydroprocessed vegetable oil) and water. The excessive use of fossil fuels has led humans to find viable and environmentally beneficial alternatives for use in various types of engines and combustion processes. With this, the use of biofuels has been one of the most sought after alternatives, and its employment in the aeronautical and aerospace sector is an example of the beneficial use of these fuels. This dissertation’s objective is to visualize and study the dynamic behaviour of a drop at the transition points between regimes, for different crossflow velocities. The drops are composed of: Jet Fuel 100%, Jet Fuel 75% - 25% HVO, Jet Fuel 50% - 50% HVO, and H2O (used as reference fluid). Considering that present legislation in the aeronautical sector allows a minimum concentration of 50% Jet Fuel in volume makes the choice of mixtures used in this study have a more restricted criterion, and therefore other mixtures are not considered. For this, an experimental facility is designed and built. Consisting of a high-speed camera, allowing the ability to visualize all the mechanisms inherent to the secondary atomization of a drop, with a specific trigger activation and desired frame rate; an infusion pump, which allows control of the insertion rate of drops into the working section. Through flat-head needles with two different internal diameters, drops of the same size are produced for all fluids; backlighting through led strips behind a diffuser glass help standardize the light captured by the camera; a properly calibrated wind-tunnel to is necessary to reach the desired speeds for regime transitions. Using the existing literature, a comparison of the phenomena and secondary atomization regimes for this new group of mixtures is made. After the dynamic study of these mechanisms, the conclusions are drawn regarding the maximum deformation rate of a drop, taking into account the dimensionless characterization of time and the dimensionless groups of relevance for this study. Drop trajectory is also presented for each regime and fluid, and a new correlation is proposed for maximum cross stream diameter evolution due to time.
- Modeling of Spray/Wall Interactions: Based on Droplet Morphology DynamicsPublication . Ribeiro, Rúben Filipe Torres; Silva, André Resende Rodrigues daThe present work has the objective of perfecting our knowledge related to spray impact, which is of paramount importance for the optimization of a wide variety of investigation areas, such as combustion systems, coating and cooling processes, and also pollutant emissions. This last referred area has been gaining more and more importance due to the obvious environmental concerns that we face in our age. For these reasons,a remarkable effort by the scientific community has been made in order to deepen the understanding of the mechanisms underlying the spray impingement process. In this dissertation, and through numerical analysis, our in-house code was adapted to reflect the impingement conditions and secondary atomization treatment proposed by Ma et al. [41]. The complex relations between incident spray and the corresponding impact surface are yet far from being duly elucidated, whereby this paper aims to bring us closer to that objective. Evidently, an extensive bibliographic review was performed about theoretical and computational concepts. There are numerous computational models in literature that intend to portray the relation between the impinging spray and the impact surface. Although, not all of these models display the complexity necessary to represent different types of conditions, such as the presence of liquid film or even the existence of a temperature so high that prevents the contact between spray and wall through the generation of a vapor layer. This phenomenon is commonly known as ”Leidenfrost effect” and is usually neglected. One of the first to emerge was proposed by Naber and Reitz, employing the KIVA code, and proposed a single threshold to determine if splash occurred or not. At first glimpse, this model was obviously flawed by way of not accounting for the conditions of occurrence of each impingement regime. Later on, Senda presented a model of their own that was able to predict not only secondary atomization and liquid film formation resulting from the impinging droplets, but also the heat transfer process present in such situation. Sendas’s model despite presenting moderate accuracy, lacked the adaptability to a wider spectrum of applications. Bai and Gosman, using the " model for the gas phase and a stochastic Lagrangian method for the spray, tried to solve this lack of adaptability by modelling the effect of wall conditions and introducing several new regimes. The results translated in improvements describing the secondary droplets, mainly through fitting secondary droplets in a chi-squared distribution and by including surface energy and film dissipation in the conservation equations. Despite these satisfactory results, this model also failed to attain general applicability. Taking into account recent literature alterations, parameters such as saturation temperature and liquid film thickness were utilized to establish more detailed boundary conditions with the intent to represent a more extended range of possible scenarios. In the application of this model a distinction was made between corona splash and prompt splash due to the fact that secondary droplets present different characteristics for each case. Questions such as expansion of the lamella, crown formation and propagation, as well as splashed film mass or transformed mass from crown to secondary droplets became of paramount importance during all the stages of the identified regime and were all detailed in this model. The size and velocity of secondary droplets depend strongly on the initial conditions of the spray at the injector exit, as well as the interaction between incident droplets, crossflow, liquid film, evaporation rate, and interposed hot wall. All these parameters are considered in this macroscopic model of the spray/wall interactions. This dissertation allows us to obtain a detailed analysis about the properties of secondary droplets. In what concerns this subject, a new regime was implemented to a specific gap of boundary conditions and denominated ”uncertain region”. This regime quantifies the probability of splash or rebound occurrence through a uniform distribution since the available information for these conditions is very scarce. Moreover, simulations are carried out for predicting the outcome of flows, including liquid film formation, droplet breakup, and spray evaporation. The numerical results are then compared against experimental data available in open literature to ascertain the predictions capabilities and validate the model.
- Numerical Modeling of Cooling Water Droplets using a Two-Way Coupling ApproachPublication . Franco, André Filipe Romão; Silva, André Resende Rodrigues daThe present dissertation focuses on the study of the process of cooling and freezing of free falling water droplets. The freezing phenomenon is of extreme relevance in aviation since the impact of drops on lifting surfaces of an aircraft and consequent accretion can lead to the occurrence of incidents and accidents. In order to prevent the formation and accretion of ice, there are several systems to combat this hazard. Critical areas of an aircraft are usually protected by these de-icing systems. However, although these methods can evaporate drops of water or melt the accreted ice, there is still the possibility of downstream ice formation due to new freezing of the ice-water mixture in unprotected areas. Thus, there is a need to study and adapt the existing physical and mathematical models for a better approximation to real-life situations, in order to contribute to a better understanding of this phenomenon and consequently lead to a reduction in the number of incidents and accidents, safety conditions. The objective of this work is to perform a numerical study with the purpose of studying the cooling of free falling water droplets for different diameters and humidity ratios. Ranz-Marshall relations are used, with and without a correction factor, in addition to the Abramzon and Sirignano approach to take into account the effects of convection. A Two-Way Coupling approach is used being the predictions compared with experimental data and numerical predictions in a One-Way Coupling approach.