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2010
Teixeira, Bruno, João Louren{\c c}o, and Diogo Sousa. "A Static Approach for Detecting Concurrency Anomalies in Transactional Memory." InForum 2010: Proceedings of InForum Simpósio de Informática. Universidade do Minho, 2010. Abstract
Programs containing concurrency anomalies will most probably exhibit harmful erroneous and unpredictable behaviors. To ensure program correctness, the sources of those anomalies must be located and corrected. Concurrency anomalies in Transactional Memory (TM) programs should also be diagnosed and fixed. In this paper we propose a framework to deal with two different categories of concurrency anomalies in TM. First, we will address low-level TM anomalies, also called dataraces, which arise from executing programs in weak isolation. Secondly, we will address high-level TM anomalies, also called high-level dataraces, bringing the programmer’s attention to pairs of transactions that the programmer has misspecified, and should have been combined into a single transaction. Our framework was validated against a set of programs with well known anomalies and demonstrated high accuracy and effectiveness, thus contributing for improving the correctness of TM programs
Elisa, M. a, B. A. b Sava, A. c Volceanov, R. C. C. d Monteiro, E. e Alves, N. e Franco, F. A. f Costa Oliveira, H. g Fernandes, and M. C. g Ferro. "Structural and thermal characterization of SiO2-P2O5 sol-gel powders upon annealing at high temperatures." Journal of Non-Crystalline Solids. 356 (2010): 495-501. AbstractWebsite

This study deals with SiO2-P2O5 powders obtained by sol-gel process, starting from tetraethoxysilane (TEOS) as precursor for SiO2 and either triethylphosphate (TEP) or phosphoric acid (H3PO4) as precursors for P2O5. In the case of samples prepared with H3PO4, TG-DTA data showed an accentuated weight loss associated to an endothermic effect up to about 140 °C, specific for the evaporation of water and ethylic alcohol from structural pores, and also due to alkyl-amines evaporation. Sol-gel samples prepared with TEP exhibited different thermal effects, depending on the type of atmosphere used in the experiments, i.e. argon or air. XRD analysis revealed that annealed sol-gel samples prepared with H3PO4 showed specific peaks for silicophosphate compounds such as Si3(PO4)4, Si2P2O9, and SiP2O7. XRD results for annealed sol-gel samples prepared with TEP indicated mainly the presence of a vitreous (amorphous) phase, which could be correlated with SEM images. The presence of SiO2 in the sample might be expected. Thus, we have searched for any SiO2 polymorph possible to crystallize. Only potential peaks of cristobalite were identified but some of them are overlapping with peaks of other crystalline phosphates. SEM analysis indicated a decrease of the amount of crystalline phases with the increase in the annealing temperature. © 2009 Elsevier B.V. All rights reserved.

Parthiban, S.a, Elangovan Ramamurthi Goncalves Martins Fortunato E. b K. a. "Structural, optical and electrical properties of indium-molybdenum oxide thin films prepared by spray pyrolysis." Physica Status Solidi (A) Applications and Materials Science. 207 (2010): 1554-1557. AbstractWebsite

Molybdenum doped indium oxide (IO) thin films were deposited on the Coring F1737 glass substrates at 400 °C by spray pyrolysis technique. TheModoping was varied between 0 and 4 at.%. The films were characterized by their structural, electrical and optical properties. The films are confirmed to be cubic bixbyite In 2O 3 with a strongest orientation along (222) for 0.5 at.% Mo, which is shifted to (400) plane when the Mo doping is increased to ≥1.2 at.%. The films deposited with 0.5 at.% Mo showed high mobility of ̃90 cm 2/Vs, resistivity of ̃6.8×10 -4ωcm and carrier concentration of ̃1.01× 1020 cm -3 with >̃73% transmittance in the visible range between 500 and 800 nm. The transmittance is well extended into near infrared region.

Drasovean, R. a, R. b Monteiro, and M. c Cherif. "Structure and morphology study of cobalt oxide doped silica nanocomposite films." AIP Conference Proceedings. Vol. 1203. 2010. 483-488. Abstract

Cobalt oxide doped silica films were synthesized by a dip-coating technique. Initial compounds were cobalt acetate Co(CH3COO)2-4H 2O and tetraethoxysilane Si(OC2H5)4. The chemical composition was studied by X-ray diffraction and UV-Vis spectroscopy. The morphology analyses were carried out by means of atomic force microscopy. The average diameter of cobalt oxide dispersed particles increases with the molar ratio Co:Si and with the aging time of the initial colloidal solution. © 2009 American Institute of Physics.

Neu, Ursula, Melissa S. Maginnis, Angelina S. Palma, Luisa J. Stroeh, Christian D. S. Nelson, Ten Feizi, Walter J. Atwood, and Thilo Stehle. "Structure-Function Analysis of the Human JC Polyomavirus Establishes the LSTc Pentasaccharide as a Functional Receptor Motif." Cell Host & Microbe. 8 (2010): 309-319. Abstract
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Pinto, R. M., R. I. Olariu, J. Lameiras, F. T. Martins, A. A. Dias, G. J. Langley, P. Rodrigues, C. D. Maycock, J. P. Santos, M. F. Duarte, M. T. Fernandez, and M. L. Costa. "Study of selected benzyl azides by UV photoelectron spectroscopy and mass spectrometry." Journal of Molecular Structure. 980 (2010): 163-171. AbstractWebsite
Benzyl azide and the three methylbenzyl azides were synthesized and characterized by mass spectrometry (MS) and ultraviolet photoelectron spectroscopy (UVPES). The electron ionization fragmentation mechanisms for benzyl azide and their methyl derivatives were studied by accurate mass measurements and linked scans at constant B/E. For benzyl azide, in order to clarify the fragmentation mechanism, labelling experiments were performed. From the mass analysis of methylbenzyl azides isomers it was possible to differentiate the isomers ortho, meta and para. The abundance and nature of the ions resulting from the molecular ion fragmentation, for the three distinct isomers of substituted benzyl azides, were rationalized in terms of the electronic properties of the substituent. Concerning the para-isomer, IRC calculations were performed at UHF/6-31G(d) level. The photoionization study of benzyl azide, with He(I) radiation, revealed five bands in the 8-21 eV ionization energies region. From every photoelectron spectrum of methylbenzyl azides isomers it has been identified seven bands, on the same range as the benzyl azide. Interpretation of the photoelectron spectra was accomplished applying Koopmans' theorem to the SCF orbital energies obtained at HF/6-311++G(d, p) level.
Pinto, R. M., R. I. Olariu, J. Lameiras, F. T. Martins, A. A. Dias, G. J. Langley, P. Rodrigues, C. D. Maycock, J. P. Santos, M. F. Duarte, M. T. Fernandez, and M. L. Costa. "Study of selected benzyl azides by UV photoelectron spectroscopy and mass spectrometry." Journal of Molecular Structure. 980 (2010): 163-171. AbstractWebsite

Benzyl azide and the three methylbenzyl azides were synthesized and characterized by mass spectrometry (MS) and ultraviolet photoelectron spectroscopy (UVPES). The electron ionization fragmentation mechanisms for benzyl azide and their methyl derivatives were studied by accurate mass measurements and linked scans at constant B/E. For benzyl azide, in order to clarify the fragmentation mechanism, labelling experiments were performed. From the mass analysis of methylbenzyl azides isomers it was possible to differentiate the isomers ortho, meta and para. The abundance and nature of the ions resulting from the molecular ion fragmentation, for the three distinct isomers of substituted benzyl azides, were rationalized in terms of the electronic properties of the substituent. Concerning the para-isomer, IRC calculations were performed at UHF/6-31G(d) level. The photoionization study of benzyl azide, with He(I) radiation, revealed five bands in the 8-21 eV ionization energies region. From every photoelectron spectrum of methylbenzyl azides isomers it has been identified seven bands, on the same range as the benzyl azide. Interpretation of the photoelectron spectra was accomplished applying Koopmans' theorem to the SCF orbital energies obtained at HF/6-311++G(d, p) level.

Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, J. N. Marat-Mendes, and Ieee. "The Study of the Molecular Movements in the Range of Glass Transition by the Final Thermally Stimulated Discharge Current Technique." Proceedings of the 2010 Ieee International Conference on Solid Dielectrics. IEEE International Conference on Solid Dielectrics-ICSD. 2010. Abstract
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Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, J. N. Marat-Mendes, and Ieee. "The Study of the Molecular Movements in the Range of Glass Transition by the Final Thermally Stimulated Discharge Current Technique." Proceedings of the 2010 Ieee International Conference on Solid Dielectrics (Icsd 2010) (2010). Abstract
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Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, J. N. Marat-Mendes, and Ieee. "The Study of the Molecular Movements in the Range of Glass Transition by the Final Thermally Stimulated Discharge Current Technique." Proceedings of the 2010 Ieee International Conference on Solid Dielectrics. IEEE International Conference on Solid Dielectrics-ICSD. 2010. Abstract

The electrical methods used to study the molecular movements are based on the movement of the dipoles under DC or AC electric field. We have proposed recently a combined measuring protocol to analyze charge injection/extraction, transport, trapping and de-trapping in polar or non-polar dielectric materials. The method is used here to analyze the molecular movements in polyimide in the temperature range from 293 to 572 K. A strong relaxation was observed around 402 K and a very weak relaxation around 345 K. This is the beta relaxation which is quite complex. As concern the behavior at high temperatures, above the beta relaxation, a high peak was observed that shifts continuously to higher temperatures as the charging temperature and/or the charging field increase. The maximum current of the peak increases and the temperature corresponding to the maximum current increases as the charging temperature and/or the charging field increase, given a direct observation of the so called cross-over effect related to current decay for sample charged at high fields and/or high temperatures.

Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, J. N. Marat-Mendes, and Ieee. "The Study of the Molecular Movements in the Range of Glass Transition by the Final Thermally Stimulated Discharge Current Technique." Proceedings of the 2010 Ieee International Conference on Solid Dielectrics. IEEE International Conference on Solid Dielectrics-ICSD. 2010. Abstract
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Carvalho, H., and V. Cruz-Machado. "A Supply Chain Mapping Framework for Resilience Modeling." 17th International Annual {EurOMA} Conference. Porto, Portugal 2010. Abstract
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Carvalho, H., S. G. Azevedo, and V. Cruz-Machado. "Supply chain performance management: lean and green paradigms." International Journal of Business Performance and Supply Chain Modelling. 2 (2010): 304-333. AbstractWebsite

Supply chain management ({SCM)} is crucial for increasing organisational effectiveness, enhancing competitiveness, customer service and profitability. Actually, the lean and green philosophies have been adopted in the {SCM} context, but nearly always separately and with little understanding of their influence on supply chain performance. Accordingly, this paper intends to propose a conceptual model that explores the relationships between lean and green practices and supply chain performance. A set of lean and green {SCM} practices and a performance measurement system are suggested. The proposed performance measures intend to evaluate the practices influence on operational, economic and environmental supply chain's performance.

Ortigueira, M. D., and FJ Coito. "System initial conditions vs derivative initial conditions." Computers & Mathematics with Applications. 59 (2010): 1782-1789. Abstract
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b Fortunato, E.a, Figueiredo Barquinha Elamurugu Barros Goņalves Park Hwang Martins V. a P. a. "Thin-film transistors based on p-type Cu2 O thin films produced at room temperature." Applied Physics Letters. 96 (2010). AbstractWebsite

Copper oxide (Cu2 O) thin films were used to produce bottom gate p-type transparent thin-film transistors (TFTs). Cu2 O was deposited by reactive rf magnetron sputtering at room temperature and the films exhibit a polycrystalline structure with a strongest orientation along (111) plane. The TFTs exhibit improved electrical performance such as a field-effect mobility of 3.9 cm2 /V s and an on/off ratio of 2× 102. © 2010 American Institute of Physics.

b Fortunato, E.a, Barros Barquinha Figueiredo Park Hwang Martins R. a P. a. "Transparent p-type SnOx thin film transistors produced by reactive rf magnetron sputtering followed by low temperature annealing." Applied Physics Letters. 97 (2010). AbstractWebsite

P-type thin-film transistors (TFTs) using room temperature sputtered SnOx (x<2) as a transparent oxide semiconductor have been produced. The SnOx films show p-type conduction presenting a polycrystalline structure composed with a mixture of tetragonal Β-Sn and α -SnOx phases, after annealing at 200 °C. These films exhibit a hole carrier concentration in the range of ≈ 1016 - 1018 cm-3; electrical resistivity between 101 - 102 cm; Hall mobility around 4.8 cm2 /V s; optical band gap of 2.8 eV; and average transmittance ≈85% (400 to 2000 nm). The bottom gate p-type SnOx TFTs present a field-effect mobility above 1 cm2 /V s and an ON/OFF modulation ratio of 103. © 2010 American Institute of Physics.

Santos, H. M., R. Carreira, M. S. Diniz, M. G. Rivas, C. Lodeiro, JJG Moura, and J. L. Capelo. "Ultrasonic multiprobe as a new tool to overcome the bottleneck of throughput in workflows for protein identification relaying on ultrasonic energy." Talanta. 81 (2010): 55-62. AbstractWebsite
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Nunes, Isabel L., and Jurek Kirakowski Usabilidade de interfaces – versão Portuguesa do Software Usability Measurement Inventory (SUMI) [Interfaces Usability – Portuguese version of the Software Usability Measurement Inventory (SUMI)]. Eds. P. Arezes, J. S. Baptista, M. P. Barroso, P. Carneiro, P. Cordeiro, N. Costa, R. Melo, A. S. Miguel, and G. P. Perestrelo. Occupational Safety and Hygiene (SHO10). Guimarães - Portugal: SPOSHO, 2010. Abstract
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Antunes, R., F. Coito, and H. Duarte-Ramos. "Using Human Dynamics to Improve Operator Performance." Emerging Trends in Technological Innovation (2010): 393-400. Abstract
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Figueiredo, Ondina M., Teresa Pereira Silva, and João Pedro Veiga. "An X-ray spectrometry and absorption spectroscopy study of blue-and-white glazes from ancient Chinese porcelains." European Conference on X-ray Spectrometry-EXRS2010. 2010. Abstract
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Figueiredo, Ondina M., Teresa Pereira Silva, and João Pedro Veiga. "An X-ray spectrometry and absorption spectroscopy study of blue-and-white glazes from ancient Chinese porcelains [Abstract]." European Conference on X-ray Spectrometry-EXRS2010. 2010. Abstract
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Santos, J. P., A. M. Costa, J. P. Marques, M. C. Martins, P. Indelicato, and F. Parente. "X-ray-spectroscopy analysis of electron-cyclotron-resonance ion-source plasmas." Physical Review A. 82 (2010): 062516. AbstractWebsite
Analysis of x-ray spectra emitted by highly charged ions in an electron-cyclotron-resonance ion source (ECRIS) may be used as a tool to estimate the charge-state distribution (CSD) in the source plasma. For that purpose, knowledge of the electron energy distribution in the plasma, as well as the most important processes leading to the creation and de-excitation of ionic excited states are needed. In this work we present a method to estimate the ion CSD in an ECRIS through the analysis of the x-ray spectra emitted by the plasma. The method is applied to the analysis of a sulfur ECRIS plasma.
Santos, J. P., A. M. Costa, J. P. Marques, M. C. Martins, P. Indelicato, and F. Parente. "X-ray-spectroscopy analysis of electron-cyclotron-resonance ion-source plasmas." Physical Review A. 82 (2010): 062516. AbstractWebsite

Analysis of x-ray spectra emitted by highly charged ions in an electron-cyclotron-resonance ion source (ECRIS) may be used as a tool to estimate the charge-state distribution (CSD) in the source plasma. For that purpose, knowledge of the electron energy distribution in the plasma, as well as the most important processes leading to the creation and de-excitation of ionic excited states are needed. In this work we present a method to estimate the ion CSD in an ECRIS through the analysis of the x-ray spectra emitted by the plasma. The method is applied to the analysis of a sulfur ECRIS plasma.

Nayak, P.K.a, Busani Elamurugu Barquinha Martins Hong Fortunato T. a E. a. "Zinc concentration dependence study of solution processed amorphous indium gallium zinc oxide thin film transistors using high-k dielectric." Applied Physics Letters. 97 (2010). AbstractWebsite

The effects of zinc concentration on the performance of solution processed amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) have been investigated using high-k aluminum titanium oxide as gate dielectric. The x-ray diffraction results confirmed that all the IGZO channel layers are amorphous. The performance of a-IGZO TFTs were investigated in the linear regime operation. Highest linear field-effect mobility of 5.8 cm2 /V s with an Ion / Ioff ratio of 6× 107 and subthreshold swing of 0.28 V/dec were obtained for the a-IGZO (311) TFTs. The obtained performance of the a-IGZO TFTs is very promising for low-voltage display applications. © 2010 American Institute of Physics.

O'Brien, S.a, Nolan Çopuroglu Hamilton Povey Pereira Martins Fortunato Pemble M. G. a M. "Zinc oxide thin films: Characterization and potential applications." Thin Solid Films. 518 (2010): 4515-4519. AbstractWebsite

Zinc oxide (ZnO) has attracted recent interest for a range of applications, including use as a transparent conductive oxide (TCO) and in gas sensor devices. This paper compares ZnO films grown using two methods designed for the production of thin films, namely sol-gel and aerosol assisted chemical vapour deposition (AACVD) for potential use in sensor and TCO applications. Materials produced by the sol-gel route were observed to be amorphous when annealed at 350 °C, but were crystalline when annealed at higher temperatures and had a relatively open grain structure when compared to the AACVD films. Electrical characterization showed that materials were highly resistive, but that their properties varied considerably when the measurements were performed in vacuum or in air. This behaviour was rapidly reversible and reproducible for room temperature measurement. In contrast materials grown by aerosol-assisted CVD were non-porous, polycrystalline and conductive. Measured electrical properties did not vary with changing measurement atmosphere. These differences are discussed in terms of the structural characterisation of the films and some comments are made regarding the suitability of both approaches for the growth of ZnO thin film sensor materials. © 2009 Elsevier B.V. All rights reserved.