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2005
Bettini, Lorenzo, Rocco de Nicola, Daniele Falassi, Marc Lacoste, Luís Lopes, Licínio Oliveira, Hervé Paulino, and Vasco T. Vasconcelos. "A Software Framework for Rapid Prototyping Run-Time Systems for Mobile Calculi." Global Computing: IST/FET International Workshop, GC 2004, Rovereto, Italy, March 9-12, 2004, Revised Selected Papers. Ed. Paola Priami, Corrado; Quaglia. Lecture Notes in Computer Science. Springer-Verlag, 2005. 179-207. Abstract
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Salema, M. I. G., APB Póvoa, and A. Q. Novais. "Design and planning of supply chains with reverse flows." Computer Aided Chemical Engineering. Eds. Luis Puigjaner, and António Espuña. Vol. 20. Elsevier, 2005. 1075-1080. Abstract

A multi-product model for the design of global supply chains with reverse flows is proposed. Two levels of decisions are considered, one strategic and one tactical. The first is modelled through a macro perspective of time where the determination of the network structure and flows is accomplished. At tactical level, a micro perspective of time is considered, where production planning and inventory management are addressed in detail. A mixed integer linear programming formulation is developed which is solved with standard Branch and Bound techniques. The model accuracy and suitability are studied using a case study.

Neves-Silva, R., N. Filatov, J. M. Lemos, and H. Unbehauen. "A dual approach to start-up of an adaptive predictive controller." IEEE Trans. Control Systems Technology. 13.6 (2005): 877-883 .
Salema, Maria Isabel Gomes, A. P. Barbosa-Póvoa, and Augusto Q. Novais. "Dynamic network design model with reverse flows." POMS 16th Annual Conference. Vol. 4643. Chicago, USA 2005. 19. Abstract2005_salema05dynamicnetwrokdesign_poms05.pdf

Much attention is currently given to the study of supply chains. Most studies are, however, only concerned with forward chains, rendering reverse chains a field insufficiently covered. Few optimization models addressing either the design of reverse networks or the simultaneous design of forward and reverse networks have been presented. We propose a MILP model for the design and planning of an integrated forward and reverse chain. While minimizing cost, the network structure is defined simultaneously with production and storage planning. Dynamic aspects are accounted for using a two-time scale, fully interconnected structure, where at a macro time the network design is performed and at a micro time the planning is optimised. The deterministic model is extended and a scenario approach is applied to account for uncertainties in demand and return of products. A case study is solved and a common structure to all scenarios is obtained, while scenario dependent policies are defined for distribution, production and storage. The model generality is corroborated with good performance results.

Rauter, A. P., M. M. Filipe, C. Prata, J. P. Noronha, M. A. Sampayo, J. Justino, and J. Bermejo. "A new dihydroxysterol from the marine phytoplankton Diacronema sp. (Haptophyta)." Fitoterapia. 76 (2005): 433-438.
Tostão, Zélia, João P. Noronha, Eurico J. Cabrita, Jorge Medeiros, Jorge Justino, Jaime Bermejo, and Amélia P. Rauter. "A Novel Pentacyclic Triterpene from Leontodon filii." Fitoterapia. 76.2 (2005): 173-180.A Novel Pentacyclic Triterpene from Leontodon filii 2005.pdf
Salema, Maria Isabel Gomes, Ana Paula Barbosa-povoa, and Augusto Q. Novais. "Redesigning a global supply chain with reverse flows." 10th International Symposium on Logistics. Lisbon, Portugal 2005. Abstract2005_salema05redesigningsc_isl05.pdf

In recent years much attention has been given to global supply chains. However, the emphasis has been on forward chains, with reverse flows been insufficiently studied. In this work, we study closed loop supply chains and analyse the impact caused by the introduction of new facility sites into an already existing supply chain. The model considers both strategic and tactical decisions allowing for the design of a global supply chain with reverse flows. The impact of the network redesign is analysed and the associated costs calculated. The obtained MILP is solved using a standard Branch and Bound solver. The results obtained prove that the proposed model handles satisfactorily the network redesign problem.

Palma, L. B., F. Coito, and R. Neves-Silva. "Robust fault diagnosis approach using analytical and knowledge based techniques applied to a water tank system." Journal of Engineering Intelligent Systems. 13.4 (2005): 237-244.
Sanguino, P., O. M. N. D. Teodoro, M. Niehus, C. P. Marques, A. M. C. Moutinho, E. Alves, and R. Schwarz. "{Structural and composition analysis of GaN films deposited by cyclic-PLD at different substrate temperatures}." Sensors and Actuators A: Physical. 121 (2005): 131-135. Abstract2005_ganfilms_sensors.pdfWebsite

GaN films were deposited by cyclic pulsed laser deposition (cyclic-PLD) at different substrate temperatures between 400 and 600◦C. Alignment of the films along the c-axis, grain size, roughness and conductivity increased with temperature. Surface elemental ratio N/Ga was determined by X-ray photoelectron spectroscopy (XPS) and was smaller for films deposited at higher temperature. A decrease of the resistivity of the films agreed with higher metallic (Ga) surface concentration. Bulk elemental ratio N/Ga, determined by Rutherford backscattering spectroscopy (RBS), was higher than the XPS ratio and showed a very small tendency to decrease with deposition temperature. At 600 ◦C, there was evidence of contamination of the films by oxygen probably resulting from diffusion from the sapphire (Al2O3) substrate. These results suggest that adjustments in the deposition conditions are needed in order to have high crystal alignment, large grain size and good N/Ga ratio.

Nunes, Isabel L., Pedro Santos, José Henriques, and Carlos Ruas Análise de Riscos numa Empresa do Sector Metalomecânico. [Risk Analysis in a Metalomecanic Company]. Eds. Guedes C. Soares, A. P. Teixeira, and P. Antão. Vol. 1. Análise e Gestão de Riscos, Segurança e Fiabilidade. Proceedings I Encontro Nacional de Riscos, Segurança e Fiabilidade, 1. Ed Salamandra, Lda, 2005. Abstract
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Nunes, Isabel L., Pedro Santos, José Henriques, and Carlos Ruas Análise de Riscos numa Empresa do Sector Metalomecânico. [Risk Analysis in a Metalomecanic Company]. Eds. Guedes C. Soares, A. P. Teixeira, and P. Antão. Vol. 1. Análise e Gestão de Riscos, Segurança e Fiabilidade. Proceedings I Encontro Nacional de Riscos, Segurança e Fiabilidade, 1. Ed Salamandra, Lda, 2005. Abstract
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Lanca, M. C., M. Fu, E. Neagu, L. A. Dissado, J. Marat-Mendes, A. Tzimas, and S. Zadeh Comparative study of space charge in the polymeric insulation of power cables using PEA, isothermal and non-isothermal currents measurements., 2005. AbstractWebsite

An understanding of space charge build-up in the polymeric insulation of power cables is important in determining how aging occurs and progresses and, also in predicting cable lifetime. In this investigation electric-field induced space charge in peelings from XLPE (cross-linked polyethylene) cables was measured using two different methods: the pulsed electro-acoustic technique (PEA) and the combined procedure of isothermal and non-isothermal charging/discharging currents (FTSDC). These two methods allow the study of space charge in highly insulating materials. Also, since electric fields of different orders of magnitude are applied to the sample in the two methods, it is possible to analyze different characteristics of the space charge traps. Prior to the measurements the samples were subjected to conditioning to remove volatiles. Cable peelings from various brands aged under different conditions (including field aged and thermally aged samples) were studied as received from the manufacturers. Some of the samples have undergone further ageing in AC electric field (50Hz) for 1000h to see the influence of further ageing on space charge build-up. The results for the different types of samples are compared in an attempt to correlate different ageing parameters.

BRITO PALMA, L., F. V. Coito, and R. NEVES DA SILVA. "Diagnosis of parametric faults based on identification and statistical methods." Decision and Control, 2005 and 2005 European Control Conference. CDC-ECC'05. 44th IEEE Conference on. IEEE, 2005. 3838-3843. Abstract
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Cabeças, José M., and Isabel L. Nunes. "Fisheries Safety Management." Enterprise and Work Innovation Studies. 1 (2005): 19-26. Abstract
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Neagu, E. R., R. M. Neagu, M. C. Lanca, A. Vassilikou-Dova, and J. N. Marat-Mendes Identification of an apparent peak by use of the final thermally stimulated discharge current technique., 2005. AbstractWebsite

The final thermally stimulated discharge current (FTSDC) technique can be used to analyze charge trapping and transport in insulating materials. The experimental conditions can be selected so that the FTSDC is mainly determined by the space charge detrapping. Measurements of the FTSDC in a wide temperature range including the local (secondary) beta relaxation and the non-local (primary) cc relaxation, for different polymers, demonstrate the existence of an apparent peak. The shift of peak temperature T-m with respect to the charging temperature T-p is analyzed. The interval T-m - T-p decreases from about 25 K to zero, as T-p approaches the glass transition T-g. T-m - T-p is lower for materials of lower conductivity. The peak width at the half maximum intensity decreases as Tp increases and the thermal apparent activation energy increases. The variations are not monotonous revealing the temperature range where the molecular motion is stronger and consequently the charge trapping and detrapping processes are affected by the strong thermal motion.

Nunes, Isabel L. Lesões Músculo-Esqueléticas Relacionadas com o Trabalho. Eds. F. Cabral, and R. Veiga. 16ª actual. ed. Higiene, Segurança e Prevenção de Acidentes. Lisbon: Verlag Dashofer, 2005. Abstract
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Nunes, Isabel L., and José M. Cabeças. "Noise Management at Work." Enterprise and Work Innovation Studies. 1 (2005): 75-81. Abstract
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Lanca, M. C., E. R. Neagu, and J. N. Marat-Mendes. "Space charge studies of aged XLPE using combined isothermal and thermostimulated current measurements." Cross-Disciplinary Applied Research in Materials Science and Technology. Ed. A. MendezVilas. Vol. 480. Materials Science Forum, 480. 2005. 501-505. Abstract

Space charge in electrically aged cross-linked polyethylene (XLPE) was studied using a procedure combining isothermal and non-isothermal measurements of charge and discharge currents. Aging is carried out using an AC field while immersing the disk-shaped samples in an ionic aqueous solution at constant temperature. After aging the samples were isothermally DC charged and discharged. Next a non-isothermal experiment with constant heating rate was performed (FTSDC). Finally the sample was kept at the highest temperature in order to completely discharge the polymer. The space charge introduced in the XLPE during aging can be analyzed from the study of the FTSDC spectra. The thermogram (FTSDC) shows a very broad peak. The peak is attributed to trapped space charge in traps with long relaxation times. It is possible to decompose it into three or four individual peaks and obtain the corresponding activation energies. The results were compared with previous ones obtained for LDPE (low density polyethylene) aged under similar conditions.

Neagu, E. R., R. M. Neagu, M. C. Lanca, and J. N. Marat-Mendes The time as a parameter to investigate the landscape of the apparent activation energies in the final thermally stimulated discharge current measurements., 2005. AbstractWebsite

The experimental results obtained in a wide range of temperatures, for polyethylene terephthalate, demonstrate that the apparent activation energy changes when the charging (polarization) time or the isothermal discharging time, prior to the final thermally stimulated discharge current measurement, are used as variable parameters. Consequently, the charging and/or discharging time can be used as a variable parameter to investigate the landscape of the apparent thermal activation energies. A continuous distribution of the traps in the range from 0.4 to 3 eV was observed. The experimental results demonstrate that there is a range of experimental conditions for which the thermal activation energy is independent of the experimental parameter values. This is the activation energy value which should be used to characterize a certain mechanism.

Neagu, E. R., R. M. Neagu, M. C. Lanca, and J. N. Marat-Mendes. "The time as a parameter to investigate the landscape of the apparent activation energies in the final thermally stimulated discharge current measurements." 12th International Symposium on Electrets (ISE 12), Proceedings (2005): 292-295. AbstractWebsite

The experimental results obtained in a wide range of temperatures, for polyethylene terephthalate, demonstrate that the apparent activation energy changes when the charging (polarization) time or the isothermal discharging time, prior to the final thermally stimulated discharge current measurement, are used as variable parameters. Consequently, the charging and/or discharging time can be used as a variable parameter to investigate the landscape of the apparent thermal activation energies. A continuous distribution of the traps in the range from 0.4 to 3 eV was observed. The experimental results demonstrate that there is a range of experimental conditions for which the thermal activation energy is independent of the experimental parameter values. This is the activation energy value which should be used to characterize a certain mechanism.

Fortunato, E., P. Barquinha, A. Pimentel, A. Goncalves, A. Marques, L. Pereira, and R. Martins Zinc oxide thin-film transistors. Eds. N. H. Nickel, and E. Terukov. Vol. 194. Zinc Oxide - A Material for Micro- and Optoelectronic Applications, 194., 2005. AbstractWebsite
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2004
Guerreiro, B., and D. Nunes Low Altitude Terrain Following Control Systems for Autonomous Helicopters. Instituto Superior Técnico, Institute for Systems and Robotics, 2004. Abstract
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Guerreiro, B., and D. Nunes Low Altitude Terrain Following Control Systems for Autonomous Helicopters. Instituto Superior Técnico, Institute for Systems and Robotics, 2004. Abstract
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Pauleta, S. R., A. Cooper, M. Nutley, N. Errington, S. Harding, F. Guerlesquin, C. F. Goodhew, I. Moura, JJG Moura, and G. W. Pettigrew. "A copper protein and a cytochrome bind at the same site on bacterial cytochrome c peroxidase." Biochemistry. 43 (2004): 14566-14576. AbstractWebsite

Pseudoazurin binds at a single site on cytochrome c peroxidase from Paracoccus pantotrophus with a K-d of 16.4 muM at 25 degreesC, pH 6.0, in an endothermic reaction that is driven by a large entropy change. Sedimentation velocity experiments confirmed the presence of a single site, although results at higher pseudoazurin concentrations are complicated by the dimerization of the protein. Microcalorimetry, ultracentrifugation, and H-1 NMR spectroscopy studies in which cytochrome c550, pseudoazurin, and cytochrome c peroxidase were all present could be modeled using a competitive binding algorithm. Molecular docking simulation of the binding of pseudoazurin to the peroxidase in combination with the chemical shift perturbation pattern for pseudoazurin in the presence of the peroxidase revealed a group of solutions that were situated close to the electron-transferring heme with Cu-Fe distances of about 14 Angstrom. This is consistent with the results of H-1 NMR spectroscopy, which showed that pseudoazurin binds closely enough to the electron - transferring heme of the peroxidase to perturb its set of heme methyl resonances. We conclude that cytochrome c550 and pseudoazurin bind at the same site on the cytochrome c peroxidase and that the pair of electrons required to restore the enzyme to its active state after turnover are delivered one-by-one to the electron-transferring heme.