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- The socio-economic impact of a Polytechnic Institution in a local economy: some insights of field researchPublication . Cunha, Jorge; Alves, João; Carvalho, Luísa; Correia, Florbela; Farinha, Luís; Fernandes, Joana; Ferreira, Manuela; Lucas, Eugénio; Nicolau, Ana; Nunes, Sandra; Nunes, Sara; Oliveira, Pedro; Pereira, Cristina; Pinto, Sandra; Silva, José ManuelHigher Education Institutions (HEI) are considered important mechanisms of regional development. However, due to the current economic recession and budget constraints, HEIs need to demonstrate the impact that their activities have on the surrounding community that contributes for its economic development. Hence, the aim of this paper is to present the results of a model to estimate the economic impact of different HEIs that are located in regions with different socio-economic development. Moreover, the common framework of analysis, whilst considering the different socio-economic realities, allows the comparisons of the results for the different HEIS.
- Lossy and lossless image encoding using multi‐scale recurrent pattern matchingPublication . Graziosi, Danillo Bracco; Rodrigues, Nuno Miguel; Silva, Eduardo A.B. da; Carvalho, Murilo B. de; Faria, Sérgio Manuel Maciel deIn this study, the authors investigate the use of multi‐scale recurrent pattern matching paradigm for lossless image compression. The multi‐scale multidimensional parser (MMP) algorithm is a successful implementation of this paradigm for lossy image compression, and can naturally perform lossless compression since it was first derived from a Lempel–Ziv lossless scheme. However, neither its recently adopted coding tools had been adapted for lossless coding nor a thorough analysis of its performance had been carried out. In this work, the authors evaluate MMP's lossless compression capability, proposing modifications for some of its predictions modes, as well as the inclusion of an adaptive prediction mode based on least squares. The residual information is also coded with well‐known techniques used in lossless compression. Experimental results for MMP show that the algorithm achieves a good performance for images such as computed generated graphics and scanned documents, whereas keeping a competitive performance for natural images. Since the algorithm's structure is exactly the same for lossless and lossy compression, the obtained results suggest that MMP is able to achieve a high compression performance for a wide range of images and rates, from lossy to lossless, without any prior analysis of the image to be coded.
- Optimization of Thermoplastic Pre-Pregs OvermouldingPublication . Carreira, Pedro; Alves, Nuno; Carina Ramos; Bártolo, Paulo J.The search for new technological concepts in the field of injection of thermoplastic polymers, in order to optimize the process and reduce cycle time, faced us with a new concept in moulding, where two different technologies are proposed to be unified. The fabric impregnated with thermoplastic is an example of a quite new product that combines the potential of polymers with long reinforcing fibres. In order to process this new product, injection of polymers and thermoforming will be applied in only one operation. To allow cycle time prediction for this new technique, changes will be made in the formulation of conventional injection cycle time, in order to comprise the new necessary stages. In this work a new approach is proposed to obtain moulded parts of thermoplastic polymers with functional fabric only in a single processing cycle. The description of the new stages and its mathematical formulation is made, in function of the time needed to complete each one. The results presented come from processing parameters optimization using the Particle Swarm Optimization (PSO) algorithm.
- Optimising anti-spam filters with evolutionary algorithmsPublication . Yevseyeva, Iryna; Basto-Fernandes, Vitor; Ruano-Ordás, David; Méndez, José R.This work is devoted to the problem of optimising scores for anti-spam filters, which is essential for the accuracy of any filter based anti-spam system, and is also one of the biggest challenges in this research area. In particular, this optimisation problem is considered from two different points of view: single and multiobjective problem formulations. Some of existing approaches within both formulations are surveyed, and their advantages and disadvantages are discussed. Two most popular evolutionary multiobjective algorithms and one single objective algorithm are adapted to optimisation of the anti-spam filters' scores and compared on publicly available datasets widely used for benchmarking purposes. This comparison is discussed, and the recommendations for the developers and users of optimising anti-spam filters are provided.
- Calibration of mirror position and extrinsic parameters in axial non-central catadioptric systemsPublication . Perdigoto, Luís; Araujo, HelderWe propose a novel calibration method for catadioptric systems made up of an axial symmetrical mirror and a pinhole camera with its optical center located at the mirror axis. The calibration estimates the relative camera/mirror position and the extrinsic rotation and translation w.r.t. the world frame. The procedure requires a single image of a (possibly planar) calibration object. We show how most of the calibration parameters can be estimated using linear methods (Direct-Linear-Transformation algorithm) and cross-ratio. Two remaining parameters are obtained by using non-linear optimization. We present experimental results on simulated and real images.
- Management of quality-related costs. The case of Portuguese companies.Publication . Pires, António Ramos; Cociorva, Aliona; Saraiva, Margarida; Novas, Jorge Casas; Rosa, ÁlvaroThe traditional view of quality-related costs (QRC) tries to justify investment in prevention as a way to reduce the costs of failure. But this static view must counter a more dynamic vision that fosters continuous improvement and assesses the costs and benefits of implementing techniques and methods of quality management, such as certification of ISO 9001systems. However, it is unknown whether such companies are also engaged in the management of QRC arising from activities undertaken, either at the level of monitoring, or coming from failures, and if such organisations verify (or not) the recovery of investments in quality. In this sense, the present article aims to provide insight into the procedures adopted by Portuguese companies in managing QRC, and to assess the extent to which management reports allow the analysis of quality costs and contribute to the related planning and control activities. The results of this study showed that there is hardly any assent to the implementation of formal mechanisms for planning and control of QRC, and to the explicit identification and segregation of those costs in management reports.
- Levodopa Incorporation in Alginate Membranes for Drug Delivery StudiesPublication . Franco, Margarida Rosa; Viana, Tânia Filipa; Biscaia, Sara; Bártolo, PauloParkinsons Disease (PD) is the second most common progressive neurodegenerative disorder and is referred as a leading cause of neurologic disability. The symptoms and signs of PD result from a decrease of dopamines level in the basal ganglia. Accordingly to this, exogenous substitution with dopamine agonists like levodopa, is used to correct the mechanical disorders at the early stages of the disease. Levodopa is referred as a standard in the treatment of PD. The modern studies of PD drug development and experimental therapeutics focuses on the concept of slowing and targeting the release of levodopa to prolong the therapeutic effect and reduce the number of administrations. The transdermal route was thought to be the best route for providing a progressive supply of levodopa to the systemic circulation. Alginate was chosen as a drug carrier because of its biocompatible and biodegradable properties and also because it has been widely used in drug delivery systems (DDS). The aim of this research work was to produce alginate membranes with and without levodopa. A solvent casting based methodology was used. Calcium chloride was assayed as crosslinking agent. Membranes were characterized using Differential Scanning Calorimetry (DSC) techniques. Drug release was evaluated using UV Spectrophotometry.
- A study on microinjection moulding using moulding blocks by additive micromanufacturingPublication . J C Vasco; Pouzada, A. S.Microinjection moulding is one of the most efficient replication methods for polymeric components in microsystems. The manufacturing of moulding blocks for complex geometries is resorting increasingly to the techniques of rapid prototyping. This development on the use of additive microtechnologies can promote the massification of microsystems within a shorter tooling development cycle time. However, the microinjection moulding process itself has mechanical and thermal demands that must be addressed and require specific consideration of the selection of the tool material. This constrains the selection of the best-suited additive manufacturing process. The current state of the art of additive manufacturing technologies at the micrometric scale favours laser sources to process layer by layer the media contained in a vat. The media type, the laser power and the laser spot size are parameters that can influence the replication tool tolerances and physical properties. This work explores the possibilities of two additive technology tooling approaches for microinjection moulding, using different materials. The research parameters included replication detailing onto the plastic part, surface roughness, microtool integrity and wear. The evaluation of these parameters was carried out using both optical and hybrid microscopy, a laser perthometer as a non-contact solution for surface roughness evaluation, scanning electron microscopy and X-ray spec-troscopy. The results of this research work showed that the processed material and technology play an important role both on surface quality and tool life, enabling criteria definition for technology selection.