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2012
Delgado-Gomes, Vasco, Jose A. Oliveira-Lima, Joao F. Martins, Celson Lima, and Pedro Pereira. "Towards to a Web Service alert software system for standard electrical protective devices." Intelligent Engineering Systems (INES), 2012 IEEE 16th International Conference on. Lisbon, Portugal 2012. 197-201. Abstract

Electrical Protective Devices are key elements in the electrical network. Their purpose is to perform fault detection in electric power systems, by analysing power system voltages and currents. In order to achieve a more centralized control, protective devices can be connected using Web Services through a Service-Oriented Architecture (SOA) approach. This work targets planning and specification of a mapping between Abstract Communication Service Interface (ACSI) Reporting and Device Profile for Web Services (DPWS) Eventing to achieve a better protective electrical devices control, obtaining an event based alert software system, replacing conventional polling-based systems.

Amaro, Pedro, Sophie Schlesser, Mauro Guerra, Eric-Olivier Le Bigot, Jean-Michel Isac, Pascal Travers, Jose Paulo Santos, Csilla Szabo, Alexandre Gumberidze, and Paul Indelicato. "Absolute Measurement of the Relativistic Magnetic Dipole Transition Energy in Heliumlike Argon." Phys. Rev. Lett.. 109 (2012): 043005. AbstractWebsite

The 1s2s 3S1 ! 1s2 1S0 relativistic magnetic dipole transition in heliumlike argon, emitted by the plasma of an electron-cyclotron resonance ion source, has been measured using a double-flat crystal x-ray spectrometer. Such a spectrometer, used for the first time on a highly charged ion transition, provides absolute (reference-free) measurements in the x-ray domain. We find a transition energy of 3104.1605(77) eV (2.5 ppm accuracy). This value is the most accurate, reference-free measurement done for such a transition and is in good agreement with recent QED predictions.

Amaro, Pedro, Sophie Schlesser, Mauro Guerra, Eric-Olivier Le Bigot, Jean-Michel Isac, Pascal Travers, Jose Paulo Santos, Csilla Szabo, Alexandre Gumberidze, and Paul Indelicato. "Absolute Measurement of the Relativistic Magnetic Dipole Transition Energy in Heliumlike Argon." Physical Review Letters. 109 (2012): 043005. AbstractWebsite

The 1s2s 3S1 - 1s2 1S0 relativistic magnetic dipole transition in heliumlike argon, emitted by the plasma of an electron-cyclotron resonance ion source, has been measured using a double-flat crystal x-ray spectrometer. Such a spectrometer, used for the first time on a highly charged ion transition, provides absolute (reference-free) measurements in the x-ray domain. We find a transition energy of 3104.1605(77) eV (2.5 ppm accuracy). This value is the most accurate, reference-free measurement done for such a transition and is in good agreement with recent QED predictions.

Faria, Duarte M. V., Válter J. G. Lúcio, and A. Pinho Ramos. "Post-punching behaviour of flat slabs strengthened with a new technique using post-tensioning." Engineering Structures. 40 (2012): 383-397. AbstractWebsite

This work presents an experimental study concerning the post-punching behaviour of flat slabs strengthened with a new technique based on post-tensioning with anchorages by bonding using an epoxy adhesive. This strengthening technique proved efficient with respect to ultimate and serviceability states. Five slab specimens were tested in the post-punching range and it was found that the post-punching resistance was on average 78{%} of the punching resistance. This paper reports the development of strand forces and slab displacements from the beginning of the tests, including the bond stresses developed at several stages of the loading process. It was observed that top reinforcement bars were capable of transmitting post-punching loads to the prestressing strands. Taking this into account and based on the load bath envisaged from the column to the slab, expressions for the vertical load capacities corresponding to the parts of the load path are presented and compared with the experimental results, showing their ability to predict both ultimate loads and modes of failure. Compared with other strengthening techniques, the one proposed here not only upgrades ultimate and serviceability behaviour but also adds post-punching resistance, which is a great advantage in the event of progressive collapse, since it may avoid the collapse of an entire structure, thus reducing the risk of material and human losses.

Parreira, P., E. Torres, C. Nunes, Nunes C. de Carvalho, G. Lavareda, A. Amaral, and M. J. Brites. "Dye-sensitized 1D anatase TiO2 nanorods for tunable efficient photodetection in the visible range." SENSORS AND ACTUATORS B-CHEMICAL. 161 (2012): 901-907. Abstract

TiO2 films with enhanced photosensitivity were deposited on alkali free glass substrates without intentional substrate heating by pulsed DC magnetron reactive sputtering with an average thickness of about 2 mu m. Three dyes, commercial N719 and two new organic dyes were impregnated in order to control the optical spectral selectivity of such films. The type of dye used proved to dramatically influence the device's response to radiation pulses. The practical breakthrough is the use of different dyes according to the region of the electromagnetic spectrum one wants to detect. Devices with photocurrent 6 orders of magnitude higher than the dark current (from similar to 2 x 10(-12) to 2 x 10(-6) A for a 100 V bias) were fabricated with a spectral response within the visible range of the electromagnetic spectrum. In addition, this approach is likely to allow for the fabrication of hybrid photodetectors on cheap heat sensible flexible polymeric substrates. (C) 2011 Elsevier B.V. All rights reserved.

Parreira, P., E. Torres, C. Nunes, C. Nunes de Carvalho, G. Lavareda, A. Amaral, and M. J. Brites. "Dye-sensitized 1D anatase TiO2 nanorods for tunable efficient photodetection in the visible range." SENSORS AND ACTUATORS B-CHEMICAL. 161 (2012): 901-907. Abstract

TiO2 films with enhanced photosensitivity were deposited on alkali free glass substrates without intentional substrate heating by pulsed DC magnetron reactive sputtering with an average thickness of about 2 mu m. Three dyes, commercial N719 and two new organic dyes were impregnated in order to control the optical spectral selectivity of such films. The type of dye used proved to dramatically influence the device's response to radiation pulses. The practical breakthrough is the use of different dyes according to the region of the electromagnetic spectrum one wants to detect. Devices with photocurrent 6 orders of magnitude higher than the dark current (from similar to 2 x 10(-12) to 2 x 10(-6) A for a 100 V bias) were fabricated with a spectral response within the visible range of the electromagnetic spectrum. In addition, this approach is likely to allow for the fabrication of hybrid photodetectors on cheap heat sensible flexible polymeric substrates. (C) 2011 Elsevier B.V. All rights reserved.

M.I., Gomes, Caeiro F., and Henriques-Rodrigues L. PORT-PPWM extreme value index estimation. Proceedings of COMPSTAT 2012., 2012. Abstract2012_compstat2012.pdf

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Inês, Cunha, Marques João Paulo, Gil Luís, Neagu E. R., Dias C. J., Marat-Mendes J. N., and Lança M. C. "Water Content Control to Improve Space Charge Storage in a Cork Derivative." Materials Science Forum. 2012. 395-400. Abstract
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L. Camarinha-Matos, J. Goes, and et al. "Raising Awareness for Value Creation Potential in Engineering Research." Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS’2012. Caparica, Portugal: DEE/FCT/UNL, 2012.
Pereira, Lu\'ıs, Pedro Barquinha, Gonçalo Gonçalves, Elvira Fortunato, and Rodrigo Martins. "{Multicomponent dielectrics for oxide TFT}." Eds. Ferechteh H. Teherani, David C. Look, and David J. Rogers. Vol. 8263. 2012. 826316–16. Abstract
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Martins, R., V. Figueiredo, R. Barros, P. Barquinha, G. Gonçalves, L. Pereira, I. Ferreira, and E. Fortunato. "{P-type oxide-based thin film transistors produced at low temperatures}." Eds. Ferechteh H. Teherani, David C. Look, and David J. Rogers. Vol. 8263. 2012. 826315–15. Abstract
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Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Vale, Tiago M., Ricardo J. Dias, and João M. Lourenço. "Uma Infraestrutura para Suporte de Memória Transacional Distribuída." INForum 2012: Proceedings of INForum Simpósio de Informática. Monte de Capraica, PT: Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2012. Abstractinforum-dstm.pdf

As técnicas e algoritmos desenvolvidos sobre diferentes infraestruturas específicas dificilmente podem ser comparados entre si. Este princípio também se aplica às infraestruturas para execução de Memória Transacional Distribuída (MTD), pois não só são muito escassas aquelas que permitem o desenvolvimento, teste e comparação de vários algoritmos e técnicas de implementação, como fornecem uma interface intrusiva para o programador. Sem uma comparação justa, não é possível aferir quais as técnicas e algoritmos mais apropriados em cada contexto de utilização (workload). Neste artigo propomos uma infraestrutura generalista, muito flexível, que possibilita a experimentação de várias estratégias de MTD, permitindo o desenvolvimento de uma grande variedade de algoritmos e de técnicas de implementação eficientes e otimizadas. Através da sua utilização, é agora possível a comparação de técnicas e algoritmos em diferentes contextos de utilização (workloads), recorrendo a uma única infraestrutura e com implicações mínimas no código da aplicação.

Sousa, Diogo G., João M. and Lourenço, Eitan Farchi, and Itai Segall. "Aplicação do Fecho de Programas na Deteção de Anomalias de Concorrência." INForum 2012: Proceedings of INForum Simpósio de Informática. Monte de Caparica, PT: Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2012. Abstractinforum-closure.pdf

Uma das estratégias para tirar partido dos múltiplos processadores disponíveis nos computadores atuais passa por adaptar código legado, inicialmente concebido para ser executado num contexto meramente sequencial, para ser agora executado num contexto multithreading. Nesse processo de adaptação é necessário proteger apropriadamente os dados que são agora partilhados e acedidos por diferentes threads concorrentes. A proteção dos dados com locks usando uma granulosidade grossa inibe a concorrência e opõe-se ao objetivo inicial de explorar o paralelismo suportado por múltiplos processadores. Por outro lado, a utilização de uma granulosidade fina pode levar à ocorrência de anomalias próprias da concorrência, como deadlocks e violações de atomicidade (high-level data races). Este artigo discute o conceito de fecho de um programa e uma metodologia que, quando aplicados em conjunto, permitem adaptar código legado para o tornar thread-safe, garantindo a ausência de violações de atomicidade na versão corrente do software e antecipando algumas violações de atomicidade que poderão ocorrer em versões futuras do mesmo software.

BAIÃO, Manuel F. C., Válter J. G. Lúcio, Fernando F. S. Pinho, and Leça A. Coelho. "Aspetos da reabilitação de edifícios antigos de alvenaria." CIRea2012 – Conferência Internacional sobre Reabilitação de Estruturas Antigas de Alvenaria. Págs. 47-62. ISBN 978-989-20-3080-7. Reitoria UNL, Lisboa 2012.
Pinho, Fernando F. S., Válter Lúcio, Luís Moura, Nuno Travassos, and Inês Almeida. "Avaliação das condições de durabilidade de ancoragens metálicas em paredes de alvenaria." CIRea2012 – Conferência Internacional sobre Reabilitação de Estruturas Antigas de Alvenaria. Págs. 81-92. ISBN 978-989-20-3080-7. Reitoria UNL, Lisboa 2012.
Wanderley, Fernando, Denis Silva da Silveira, João Araújo, and Maria Lencastre:. "Generating feature model from creative requirements using model driven design." First International Workshop on Requirements Engineering Practices on Software Product Line Engineering (REPOS 2012). Salvador, Brazil 2012.
Barra, Ana T. P., Fernando F. S. Pinho, and Válter J. G. Lúcio. "Caracterização física e mecânica de argamassas não estruturais, com agregados finos reciclados." 4º Congresso Português de Argamassas e ETICS. Coimbra 2012.
Lopes, T. C., and M. P. Amado. "Prefabricação Aplicada ao Contexto da Reabilitação de Edifícios." 2ª Conferência de Reabilitação Sustentável de Edifícios no Espaço Lusófono. Caparica: FCT UNL - MAMAOT CV, 2012.
Barra, Ana T. P., Fernando F. S. Pinho, and Válter J. G. Lúcio. "Utilização de agregados reciclados em argamassas não estruturais." CRSEEL 2012 - 2ª Conferência Construção e Reabilitação Sustentável de Edifícios no Espaço Lusófono. FCT UNL, Monte de Caparica 2012.
Lucas, Vanessa, and Miguel P. Amado Vantages of Certification of Sustainable Construction. BSA 2012 – 1st International Conference on Building Sustainability Assessment. Porto, PT: Green Lines Institute, 2012.
Bonifácio, V. D. B., VG Correia, M. G. Pinho, J. C. Lima, and A. Aguiar-Ricardo. "Blue emission of carbamic acid oligooxazoline biotags." Materials Letters. 81 (2012): 205-208. AbstractWebsite
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