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2013
Strganac, Christopher, Louis L. Jacobs, Kurt M. Ferguson, Michael J. Polcyn, Octávio Mateus, Anne S. Schulp, and Maria Luísa Morais Late Cretaceous marine reptiles and cooling at the South Atlantic coast inferred through stable oxygen isotopes of Inoceramus from the Namibe Basin, Angola. Geological Society of America Abstracts with Programs. Vol. 45, No. 7, p.0., 2013.
Pereira, Pedro, Helena Fino, Mourad Fakhfakh, Fernando Coito, and Mário Ventim-Neves. "LC-VCO Design Challenges in the Nano-Era." Analog/RF and Mixed-Signal Circuit Systematic Design. Eds. Mourad Fakhfakh, Esteban Tlelo-Cuautle, and Rafael Castro-Lopez. Vol. 233. Lecture Notes in Electrical Engineering, 233. Springer Berlin Heidelberg, 2013. 363-379. Abstract

The progressive scaling of CMOS technology towards nanometre sizes has made the implementation of highly integrated systems for the wireless communication systems possible. Additionally, higher speed, lower power consumption and area reduction has been reached. Due to the high-density integration needs, as well as to low cost fabrication, RF applications, such as the LC-voltage controlled oscillator (LC-VCO), are usually implemented in CMOS technology. The complexity of designing LC-VCOs has lead to the development of several design methodologies. This chapter introduces an optimization based methodology for the design of LC-VCOs, where its efficiency is granted by the use of analytical models to characterize the active and passive elements’ behaviour.

Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Linear and nonlinear analysis of bond-slip models for interfaces between FRP composites and concrete." Composites Part B: Engineering. 45 (2013): 1554-1568. AbstractWebsite

The paper analyses different analytical and numerical solutions for the debonding process of the FRP-to-concrete interface on shear tests with the FRP plate submitted to a tensile load in one of its ends. From the point of view of the state of the art, two different ways of finding the bond-slip curve from experiments are discussed and analysed. Essentially, three different linear bond-slip models, one exponential model and another power based function are employed in the numerical process. The results are analysed and compared. The differences found in the stress field along the interface, maximum load, maximum slip, ultimate slip, fracture energy and effective bond length are reported. The load-slip behaviour is also presented for the linear and non-linear models herein studied and the influence of the local bond-slip model on the debonding process is discussed. The numerical integration process used on the present study proved to be coherent with the analytical expressions determined for the linear bond-slip models and allowed to verify that maximum load transmittable to the FRP plate is influenced by the square root of the FRP stiffness and fracture energy even when nonlinear bond-slip models are assumed.

Rybarczyk, Y., Fonseca J., and Martins R. "Lisling 3D: a serious game for the treatment of portuguese aphasic patients." 12th conference of the Association for the Advancement of Assistive Technology in Europe. Vilamoura, Portugal 2013. copy.pdf
Corcho, A. J., J. D. Silva, and F. Oliveira. "Local and global well-posedness for the critical Schrödinger-Debye system." Proceedings of the American Mathematical Society. 141 (2013): 3485-3499.Website
Caeiro, F., M. I. Gomes, and L. Henriques-Rodrigues A location invariant probability weighted moment EVI-estimator. Notas e Comunicações do CEAUL 30/2013, 2013.2013_30_port-ppwm-final.pdf
Long-term Behaviour of Railway Transitions under Dynamic Loading. Eds. Manuel A. G. Silva, and Paul Hölscher. Universidade Nova de Lisboa. Lisbon, 2013.
Abdollahvand, S., R. Santos-Tavares, and J. Goes A Low-Voltage CMOS Buffer for RF Applications Based on a Fully-Differential Voltage-Combiner. Doctoral Conference on Computing, Electrical and Industrial Systems (DoCEIS’2013). Caparica, Portugal: IFIP Advances in Information and Communication Technology, 2013.
Passos, F., M. H. Fino, E. Roca, R. Gonzalez-Echevarria, and F. V. Fernandez Lumped element model for arbitrarily shaped integrated inductors-A statistical analysis. IEEE International Conference on Microwaves, Communications, Antennas and Electronics Systems. Telaviv, Israel: IEEE, 2013.
Duarte, Susana, and V. Cruz-Machado. "Lean and green supply chain initiatives: A case study." IIE Annual Conference and Expo 2013. Institute of Industrial Engineers, 2013. 2168-2177. Abstract

Lean and green have moved from a trend to a business imperative to improve the supply chain. This research aims to focus on providing the basic mechanisms for a lean-green business model implementation. Based on standardized management business models, several {"}near common{"} categories were defined as key criteria for lean-green supply chain implementation including leadership, people, strategic planning, stakeholders, processes and results. The fundamental research question is how lean-green supply chain can be integrated in and compatible, using initiatives that support both, a lean and a green approach, in all selected categories. To attain the paper objective, in a first stage, a conceptual framework was proposed to define the lean-green initiatives. In a second stage, multiple case studies in automotive supply chain were performed to test qualitatively the validity of the proposed conceptual framework, testing how these initiatives are being implemented in real world. From the case study, a model is suggested, which involves a roadmap to achieve a successful lean-green implementation. The proposed model can be the basis for further research in lean-green supply chain contributing to understand in which moment the lean and green initiatives should be relevant.

Duarte, Susana, and V. Cruz-Machado. "Lean and green: A business model framework." Proceedings of the Sixth International Conference on Management Science and Engineering Management - Focused on Electrical and Information Technology. Vol. 185 LNEE. Lecture Notes in Electrical Engineering, 185 LNEE. 2013. 751-759. Abstract

Going lean and green is a trend that identifies new business opportunities for organizational improvement and for competitiveness. Besides, there are quality awards to assist organizations to improve their performance among them the Shingo Prize, the Malcom Baldrige National Quality Award, the European Foundation for Quality Management. The aim of this study is to develop a conceptual framework for lean and green business organizations. To attain the paper objective in a first stage a comparison between quality awards is developed to provide a comprehensive understanding of each framework and to explore how they assist to modeling a lean and green organization. After defining lean and green management approaches, it seeks to cross-reference between the awards frameworks and lean and green culture; a number of assessment guidelines and criteria were designed to connect and integrate lean and green principles and tools. It is proposed seven different criteria and respective criterion score to assess a lean-green business organization.

Geng, Yong, Pedro Brogueira, Joao Luis Figueirinhas, Maria Helena Godinho, and Pedro Lúcio Almeida. "Light shutters from nanocrystalline cellulose rods in a nematic liquid crystal." Liquid Crystals. 40.6 (2013): 769-773. Abstract
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Brás, R., J. O. Cerdeira, D. Alagador, and M. B. Araújo. "Linking habitats for multiple species." Environmental Modelling and Software. 40 (2013): 336-339. Abstract
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Geng, Yong, David Seč, Pedro L. Almeida, Oleg D. Lavrentovich, Slobodan Žumer, and Maria H. Godinho. "Liquid crystal necklaces: cholesteric drops threaded by thin cellulose fibres." Soft Matter. 9.33 (2013): 7928-7933. Abstract
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Diniz, M. S., A. P. A. De Matos, J. Lourenço, L. Castro, I. Peres, E. Mendonça, and A. Picado. "Liver alterations in two freshwater fish species (Carassius auratus and Danio rerio) following exposure to different TiO2 nanoparticle concentrations." Microscopy and Microanalysis. 19 (2013): 1131-1140. AbstractWebsite
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Faita, FL, AC Trindade, M. H. Godinho, and IH Bechtold. "Luminescent elastomeric Janus particles." Journal of colloid and interface science. 410 (2013): 124-130. Abstract
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2012
Guimarães, Diana, Maria Luisa Carvalho, Vera Geraldes, Isabel Rocha, Luís Cerqueira Alves, and Jose Paulo Santos. "Lead in liver and kidney of exposed rats: Aging accumulation study." J. Trace Elem. Med Biol.. 26 (2012): 285. AbstractWebsite

The concentration of lead in liver and kidneys of Wistar rats, fed with lead since fetal period in relation to their age and to a control group, was determined. A group of rats was exposed to lead acetate (n=30) in drinking water and the other group was exposed to normal water (n=20). Samples were collected from rats aging between 1 and 11 months and were analyzed by Energy Dispersive X-ray Fluorescence (EDXRF) without any chemical preparation. The EDXRF results were assessed by the PIXE (Proton Induced X-ray Emission) technique. The formaldehyde used to preserve the samples was also analyzed by ETAAS (Electro-Thermal Atomic Absorption Spectrometry) in order to verify if there was any loss of lead from the samples to the formaldehyde. We found that the loss was not significant (<2%). Concerning the mean values of the lead concentration measured in the contaminated soft tissues, in liver they range from 6 to 22μgg(-1), and in kidneys from 44 to 79μgg(-1). The control rats show, in general, values below the EDXRF detection limit (2μgg(-1)). The ratio kidney/liver ranges from 2 to 10 and is strongly positively correlated with the age of the animals. A Spearman correlation matrix to investigate the correlation between elemental concentrations and the dependence of these concentrations with age showed that there is a strong positive correlation with age for lead in the liver but not in the kidney. The correlation matrix showed also that the concentration of lead in these two soft tissues is not correlated. The lead accumulation in liver is made by different plateaus that strongly decrease with age. It was verified the existence of two levels of accumulation in kidney, not very highlighted, which might be indicative of a maximum accumulation level for lead in kidney.

Guimarães, Diana, Maria Luisa Carvalho, Vera Geraldes, Isabel Rocha, Luís Cerqueira Alves, and Jose Paulo Santos. "Lead in liver and kidney of exposed rats: Aging accumulation study." Journal of Trace Elements in Medicine and Biology. 26 (2012): 285. AbstractWebsite

The concentration of lead in liver and kidneys of Wistar rats, fed with lead since fetal period in relation to their age and to a control group, was determined. A group of rats was exposed to lead acetate (n=30) in drinking water and the other group was exposed to normal water (n=20). Samples were collected from rats aging between 1 and 11 months and were analyzed by Energy Dispersive X-ray Fluorescence (EDXRF) without any chemical preparation. The EDXRF results were assessed by the PIXE (Proton Induced X-ray Emission) technique. The formaldehyde used to preserve the samples was also analyzed by ETAAS (Electro-Thermal Atomic Absorption Spectrometry) in order to verify if there was any loss of lead from the samples to the formaldehyde. We found that the loss was not significant (<2%). Concerning the mean values of the lead concentration measured in the contaminated soft tissues, in liver they range from 6 to 22μgg(-1), and in kidneys from 44 to 79μgg(-1). The control rats show, in general, values below the EDXRF detection limit (2μgg(-1)). The ratio kidney/liver ranges from 2 to 10 and is strongly positively correlated with the age of the animals. A Spearman correlation matrix to investigate the correlation between elemental concentrations and the dependence of these concentrations with age showed that there is a strong positive correlation with age for lead in the liver but not in the kidney. The correlation matrix showed also that the concentration of lead in these two soft tissues is not correlated. The lead accumulation in liver is made by different plateaus that strongly decrease with age. It was verified the existence of two levels of accumulation in kidney, not very highlighted, which might be indicative of a maximum accumulation level for lead in kidney.

S. Abdollahvand, J. Goes, and et al. "Low Phase-Noise Temperature Compensated Self-Biased Ring-Oscillator." IEEE International Symposium on Circuits and Systems (ISCAS'2012). Seoul, South Korea: IEEE, 2012.
M., Cabrita, Cruz-Machado V., and Grilo A. "Linking knowledge management and intellectual capital: An evidence based on Portuguese banks study." International Conference on Innovation Management and Technology Research. 2012. 417-422. Abstract
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Pereira, Pedro, Helena Fino, and M. Ventim-Neves. "LC-VCO design methodology based on evolutionary algorithms." Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD), 2012 International Conference on. Seville - Spain 2012. 189-192. Abstract

In his paper the design of LC-VCOs is addressed. Due to the high-density integration needs as well as to low cost fabrication, RF applications are usually implemented in CMOS technology. However, this technology development brought up several issues such as the degradation of on-chip LC tank quality factor, yielding VCO's phase noise limitation. To overcome phase-noise limitations, optimization design methodologies are usually used. Since electromagnetic simulations are timely expensive, model based approaches are needed. In this work the characterization of the oscillator behaviour is guaranteed by a set of analytical models describing each circuit element performance. A set of working examples for UMC130 technology, aiming the VCO phase noise and power consumption optimization, is addressed. The results presented, spotlight the potential of the proposed design methodology, combined with a GA optimization procedure, for an accurate and timely efficient oscillator design. The accuracy of the results is checked against HSPICE/RF simulator.

Araújo, R., R. Castanhinha, O. Mateus, and R. Martins Late Jurassic theropod embryos from Porto das Barcas, Lourinhã formation, Portugal. Journal of Vertebrate Paleontology, Program and Abstracts, 2012, ISSN 1937-2809 ., 2012. Abstractaraujo_et_al_mateus_2012_dinosaur_eggs_portugal_svp_2012_abstract_book_meeting_abstracts.pdf.pdf

A clutch of several crushed eggs and embryos from the Late Jurassic (near the Kimmeridgian-Tithonian
boundary), Lourinhã Formation, Portugal contains a complete maxilla, erupted and scattered teeth,
and presacral vertebrae. The maxilla bears four teeth separated by individualized interdental plates,
the dorsal process of the maxilla is confluent with the maxillary body, the ventral rim of the antorbital
fossa is parallel to the tooth row, and the anterior border of the maxilla forms a right angle with the
ventral margin. The teeth are conical and recurved distally with carinae on mesial and distal sides. The
vertebrae are amphiplatyan, with a ventral pair of neurovascular foramina and heavily pitted articular
facets. These fossils allow unambiguous association of basal theropod osteology (Megalosauroidea) with
a new eggshell morphotype. Synchrotron micro-computed tomographic scanning (SRμCT), scanning
electron microscopy, and thin-sections under polarized and normal light revealed that the outer
ornamentation of the eggshell is composed of anastomosing ridges and islets, the pores communicate
near the outer region of the eggshells, and in radial section they are irregular canals that ramify towards
the surface. Micro-proto induced x-ray emission (micro-PIXE) analysis of the eggshell (excluding pores)
revealed the presence of Mg, Fe, Mn (0.33%, 0.27% and 0.18%, respectively) and several trace elements,
with a corresponding loss of Ca (39.4% detected but 40.0% expected for calcite), which suggests minimal
eggshell diagenesis. The eggshells do not luminesce, which could imply that no diagenetic alteration
took effect. However, the quenching effect of Fe2+ has to be taken into consideration. Conversely,
luminescence is observed in the pores since they are filled with sediment, composed of phyllosilicates,
as revealed by SRμCT, micro-PIXE and x-ray diffraction analyses.

Guimarães, D., M. L. Carvalho, M. Becker, A. von Bohlen, V. Geraldes, I. Rocha, and J. P. Santos. "Lead concentration in feces and urine of exposed rats by x-ray fluorescence and electrothermal atomic absorption spectrometry." X-Ray Spectrom.. 41 (2012): 80. Abstract

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"Learning introductory physics with computational modelling and interactive environments." Proceedings of the GIREP-EPEC 2011 Conference - Physics Alive. Jyvaskyla: University of Jyvaskyla, 2012. 208-213.
Guimarães, D., M. L. Carvalho, M. Becker, A. von Bohlen, V. Geraldes, I. Rocha, and J. P. Santos. "Lead concentration in feces and urine of exposed rats by x-ray fluorescence and electrothermal atomic absorption spectrometry." X-Ray Spectrometry. 41 (2012): 80. AbstractWebsite

Measurements made in feces and urine of Wistar rats exposed to lead acetate (n = 20) in drinking water since the fetal period were compared with those obtained from a control group (n = 20) in order to assess the age influence on Pb excretion. The measurements were made in different collections of rats aging between 1 and 11 months. To determine the Pb content of the samples, total reflection X-ray fluorescence (TXRF) and electrothermal atomic absorption spectrometry (ETAAS) were used for the urine samples and energy dispersive X-ray fluorescence (EDXRF) was used for the feces.The results show high concentrations of Pb being eliminated from the organism by urine and feces in contaminated rats. Values vary from (600`140)mgl1 to (5 460`115)mgl1 in urine and from (4 500`300)mgg1 to (11 400`3 300)mgg1 in dry feces. The control rats show, in general, low lead concentrations or below detection limits. The fecal/urinary ratio was studied. It was shown to be about three to four orders of magnitude and positively correlated with time. It was verified in feces and urine that excretion decreases with the animal age and that this decrease is made by different levels of excretion. The excretions of Pb in urine and in feces are positively correlated.A good agreement was found between the results obtained with TXRF and ETAAS for urine samples. This work also stresses the suitability of these techniques in the study of Pb intoxication.