Percorrer por data de Publicação, começado por "2013-04"
A mostrar 1 - 10 de 12
Resultados por página
Opções de ordenação
- Os antecedentes da e-satisfação à marca Booking.comPublication . Marques, Alzira; Cruz, Raquel SilvaAs relações “cliente - fornecedor” são cada vez mais valiosas e menos consistentes, sobretudo no contexto online. Assim, o fornecedor procura tornar um visitante do website num cliente satisfeito e um cliente satisfeito num cliente leal, como condição para se tornar mais competitivo. Compreender o que determina a satisfação online é o principal objetivo deste estudo. Assim, com base na informação recolhida através de questionário numa amostra de 104 clientes do portal Booking.com, efetuou-se o estudo dedutivo, transversal e de natureza quantitativa, com a finalidade de estudar o impacto das variáveis características do portal e da personalidade dos consumidores online na e-satisfação à marca Booking.com. Os resultados evidenciaram que as características do website têm capacidade para explicar a e-satisfação.
- 3D deformations by means of monogenic functionsPublication . Ferreira, Milton; Morais, JoãoIn this paper, the authors compute the coefficient of quasiconformality for monogenic functions in an arbitrary ball of the Euclidean space $\mathbb{R}^3$. This quantification may be needed in applications but also appear to be of intrinsic interest. The main tool used is a 3D Fourier series development of monogenic functions in terms of a special set of solid spherical monogenics. Ultimately, we present some examples showing the applicability of our approach.
- Effect of the foam core density on the bending response on sandwich compositesPublication . Capela, C.; Ferreira, J. A. M.; Costa, J. D.This paper presents the results of a current study of sandwich panels manufactured by using homogeneous and multilayer core foams with the purpose of improving specific flexural stiffness modulus. In the present study, the core foams were produced by using Verre ScotchitTM-K20 hollow microspheres manufactured by 3M and the selected binder resin was epoxy 520 with hardener 523. The skin was a 2 mm thick carbon/epoxy laminate. The ARAMIS technique was used as an alternative technique to obtain accurate displacement fields. It was concluded that the multilayered panels with different loads of microspheres, putting higher percentage of microsphere in the center and lower in the outer layers, have also higher resistance and stiffness than the panels with homogeneous microsphere percentage cores. It was observed that both properties have a tendency to increase when the displacement rate increases from 0.5 mm/min to 10 mm/min for all architectures. Experimental stiffness agrees well with analytical model predictions. © 2013 The Korean Fiber Society and Springer Science+Business Media Dordrecht.
- Modeling centrality measures in social network analysis using bi-criteria network flow optimization problemsPublication . Gómez, Daniel; Figueira, José Rui; Eusébio, AugustoCentrality measures play an important role in the field of network analysis. In the particular case of social networks, the flow represents the way in which information passes through the network nodes. Freeman et al. (1991) were the first authors to relate centrality measures to network flow optimization problems in terms of betweenness, closeness, and the influence of one node over another one. Such measures are single dimensional and, in general, they amalgamate several heterogeneous dimensions into a single one, which is not suitable for dealing with most real-world problems. In this paper we extend the betweenness centrality measure (or concept) to take into account explicitly several dimensions (criteria). A new closeness centrality measure is defined to deal not only with the maximum flow between every ordered pair of nodes, but also with the cost associated with communications. We shall show how the classical measures can be enhanced when the problem is modeled as a bi-criteria network flow optimization problem.
- A modified slant shear test designed to enforce adhesive failurePublication . Saldanha, Rui; Júlio, Eduardo; Dias-da-Costa, Daniel; Santos, PedroPresently, there are several tests available to evaluate the adhesion between concrete layers cast at different times. Among these, the Slant Shear Test (SST) has a wide spread use, mainly for being sensitive to the roughness of the interface surface, one of the most influencing parameters in this scope, but also because of the simplicity of the experimental setup. However, the major drawback of this test is the fact of being often obtained cohesive (monolithic) failures, therefore providing a lower bound of the interface strength, which is related with the concrete compressive strength. To definitely solve this issue, i.e., to enforce adhesive (interface debonding) failures in all situations, the 'Modified Slant Shear Test' (M-SST) was herein designed and developed. Both numerical and experimental tests have been conducted to validate this new method. All relevant conclusions are presented. In summary, it can be stated that the M-SST always enforces adhesive failure, therefore allowing to accurately assessing the adhesion of concrete-to-concrete interfaces.
- Localization and navigation of a mobile robot in an office-like environmentPublication . Alves, Paulo; Costelha, Hugo; Neves, CarlosThis article focuses on the localization and navigation of a mobile differential robot in an indoor office-like environment. These are fundamental issues to service robotics, which is a branch with a strong market growth. The work implements a vision tracking system, environment mapping, route planning and navigation for an autonomous robot application inside services buildings. One goal of the methodology is its application with low cost equipment. The test bed chosen was a Pioneer P3-DX robot [16] in a service building, with an attached USB webcam, pointed at the ceiling to take advantage of the position of the light fixtures as natural landmarks. The robot location is estimated through two distinct probabilistic methods: a particle filter, when there is no information about the starting location of the robot, and the Kalman filter, given the convergence of the particle filter. Both methods use the detection of light fixtures together with the robot kinematics as information to estimate the pose. The mapping of the environment and its obstacles is obtained from the localization estimates and the information gathered by ultrasound sensors, representing the entire navigation space discretized in the form of an occupation grid. Planning the navigation path is determined by a simple search algorithm, namely the Wavefront algorithm, based on the information contained in the occupancy grid. For a given path, navigation is performed with obstacle avoidance using the virtual forces method. Replanning is used to recover from local minima situations.
- Improved osteoblast cell affinity on plasma-modified 3-D extruded PCL scaffoldsPublication . Domingos, M.; Intranuovo, F.; Gloria, A.; Gristina, R.; Ambrosio, L.; Bártolo, P. J.; Favia, P.Cellular adhesion and proliferation inside three-dimensional synthetic scaffolds represent a major challenge in tissue engineering. Besides the surface chemistry of the polymers, it is well recognized that scaffold internal architecture, namely pore size/shape and interconnectivity, has a strong effect on the biological response of cells. This study reports for the first time how polycaprolactone (PCL) scaffolds with controlled micro-architecture can be effectively produced via bioextrusion and used to enhance the penetration of plasma deposited species. Low-pressure nitrogen-based coatings were employed to augment cell adhesion and proliferation without altering the mechanical properties of the structures. X-ray photoelectron spectroscopy carried out on different sections of the scaffolds indicates a uniform distribution of nitrogen-containing groups throughout the entire porous structure. In vitro biological assays confirm that plasma deposition sensitively promotes the activity of Saos-2 osteoblast cells, leading to a homogeneous colonization of the PCL scaffolds.
- O Marketing Relacional e a fidelização dos estudantes: um estudo aplicado ao CCSo da UFMA-Brasil e à ESTG do IPL-PortugalPublication . Mendes, Maria Raimunda Marques; Marques, Alzira Maria AscensãoNos últimos anos, grandes mudanças na política, governança, estrutura e status de ensino superior têm sido realizadas em todo o mundo. As mudanças ambientais, como a privatização,diversificação, descentralização, internacionalização e aumento da concorrência são comuns à maioria dos países. Estas mudanças têm um efeito sobre como as Instituições do Ensino Superior (IES) operam hoje em dia e como são com são percecionadas pelos seus stakeholders. Face ao exposto, algumas IES estão aplicando o marketing para ganhar vantagem competitiva. A captação de estudantes é importante, mas a fidelização dos seus diplomados revela-se de maior importância, uma vez que se traduz não apenas no regresso à IES para novas formações, mas na sua recomendação. Nesse contexto, este estudo tem como objetivo verificar a utilidade da orientação para o estudante das IES, pelo que nos propomos estudar a influência das práticas do Marketing Relacional na satisfação e fidelização dos estudantes. Para o efeito, escolhemos para objeto de estudo duas IES: o Centro de Ciências Sociais (CCSo) da Universidade Federal do Maranhão- Brasil e a Escola Superior de Tecnologia e Gestão (ESTG) do Instituto Politécnico de Leiria- Portugal e como unidade de análise os estudantes da licenciatura dessas duas instituições. Assim, com base na informação recolhida através de questionário numa amostra de 1007 estudantes efetuou-se o estudo quantitativo e transversal, com a finalidade de estudar as relações entre as variáveis de um modelo concetual deduzido da revisão de literatura sobre marketing relacional. Os resultados evidenciaram a importância do Marketing Relacional na satisfação dos estudantes e a relação entre as variáveis chave do marketing relacional: satisfação, confiança, compromisso e fidelização dos estudantes.Este estudo mostrou que as IES devem ver o marketing como uma oportunidade de melhorar o seu desempenho e adotar o marketing relacional que privilegie e a fidelização dos seus diplomados e que a satisfação destes facilite a captação de novos estudantes através da recomendação.
- Leiria, Cidade Educadora: Teatro, Educação e CidadaniaPublication . Pedrosa, Cecília Maria Domingues; Ferreira, José Brites; Santos, Tânia Cristina Simões de Matos dos
- Computational technologies in tissue engineeringPublication . Almeida, H. A.; Bártolo, P. J.In last decades, many advances have been made in order to aid the medical community. Numerous computational technologies have been developed and improved the efficiency in diagnostic and treatment of many diseases. Many of the technologies were developed with the main goal of aiding in the research of genetic and viral diseases. Tissue engineering is a multidisciplinary field that requires the combined effort of cell biologists, engineers, material scientists, mathematicians, geneticists, and clinicians toward the development of biological substitutes that restore, maintain, or improve tissue function. The success of this emerging medical domain relies on the current technological advances. This paper presents an overview of the existing computational technologies that have been implemented in tissue engineering and the design of scaffolds for tissue engineering applications. These computational technologies contemplate medical imaging processing, numerical calculations (structural, vascular and topological) and biofabrication techniques necessary for the scaffolds optimum design and production.