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2012
Azevedo, S. G., H. Carvalho, and V. Cruz-Machado. "Proposal of a conceptual model to analyse the influence of LARG practices on manufacturing." Journal of Modern Accounting and Auditing. 8 (2012): 174-184. AbstractWebsite

The main objective of this paper is to propose a conceptual model about the influence of lean, agile, resilient, and green ({LARG)} practices on supply chain operational, economic and environmental performance. This model is based on the literature review about the four supply chain management paradigms and also performance measurement systems. This paper contributes to the literature by introducing a new model to improve the leanness, agility, resilience, and greenness of manufacturing supply chains. Among the suggested {LARG} practices, the ones influencing more the supply chain performance are the just in time and also the supplier relationships. Also the supply chain performance measures with more {LARG} practices influencing them are the inventory levels and the time, that is, the supply chain’s operational performance is the most affected by the simultaneous paradigms deployment in the supply chain.

Pereira, Pedro, Fernando Coito, and Helena Fino. "PSO-Based Design of RF Integrated Inductor." Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2012. Eds. Luis Camarinha-Matos, Ehsan Shahamatnia, and Gonçalo Nunes. Vol. 372. IFIP Advances in Information and Communication Technology, 372. Costa de Caparica - Portugal: Springer Boston, 2012. 475-482. Abstract

This paper addresses an optimization-based approach for the design of RF integrated inductors. The methodology presented deals with the complexity of the design problem by formulating it as a multi-objective optimization. The multi-modal nature of the underlying functions combined with the need to be able to explore design trade-offs leads to the use of niching methods. This allows exploring not only the best trade-off solutions lying on the Pareto-optimum surface but also the quasi-optimum solutions that would be otherwise discarded. In this paper we take advantage of the niching properties of lbest PSO algorithm using ring topology to devise a simple optimizer able to find the local-optima. For the efficiency of the process analytical models are used for the passive/active devices. In spite the use of physics-based analytical expressions for the evaluation of the lumped elements, the variability of the process parameters is ignored in the optimization stage due to the significant computational burden it involves. Thus in the final stage both the Pareto-optimum solutions and the quasi-optimum solutions are evaluated with respect to the sensitivity to process parameter variations.

Pereira, Pedro, Fernando Coito, and Helena Fino PSO-Based Design of RF Integrated Inductor. Doceis 2012. Caparica, Pt: Springer, 2012.
Cunha, Jácome, João Paulo Fernandes, Christophe Peixoto, and João Saraiva. "A Quality Model for Spreadsheets." Proceedings of the 8th International Conference on the Quality of Information and Communications Technology, Quality in ICT Evolution Track. 2012. 231-236. Abstractquatic2012.pdf

In this paper we present a quality model for spreadsheets, based on the ISO/IEC 9126 standard that defines a generic quality model for software. To each of the software characteristics defined in the ISO/IEC 9126, we associate an equivalent spreadsheet characteristic. Then, we propose a set of spreadsheet specific metrics to assess the quality of a spreadsheet in each of the defined characteristics. In order to obtain the normal distribution of expected values for a spreadsheet in each of the metrics that we propose, we have executed them against all spreadsheets in the large and widely used EUSES spreadsheet corpus. Then, we quantify each characteristic of our quality model after computing the values of our metrics, and we define quality scores for the different ranges of values. Finally, to automate the atribution of a quality score to a given spreadsheet, according to our quality model, we have integrated the computation of the metrics it includes in both a batch and a web-based tool.

Gião, R., V. Lúcio, and C. Chastre Seismic Strengthening of RC Beam-Column Connections. 15th World Conference on Earthquake Engineering. Lisbon, 2012. Abstract

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Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, Pedro Martins, and João Saraiva. "SmellSheet Detective: A Tool for Detecting Bad Smells in Spreadsheets." Proceedings of the 2012 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '12. Washington, DC, USA: IEEE Computer Society, 2012. 243-244. Abstractvlhcc12-td.pdf

This tool demo paper presents SmellSheet Detective: a tool for automatically detecting bad smells in spreadsheets. We have defined a catalog of bad smells in spreadsheet data which was fully implemented in a reusable library for the manipulation of spreadsheets. This library is the building block of the SmellSheet Detective tool, that has been used to detect smells in large, real-world spreadsheet within the EUSES corpus, in order to validate and evolve our bad smells catalog.

Carlucci, A., M. Raimondo, J. Santos, and AJL Phillips. "Species of Plectosphaerella causing root and collar rot of cucurbits and other hosts in Southern Italy." Persoonia. 28 (2012): 34-48.
Florentino, Carlos, and Ana Cristina Casimiro. "Stability of affine G-varieties and irreducibility in reductive groups." Int. J. Math.. 23 (2012): 30. Abstract

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Sousa, Ana M. M., Simone Morais, Maria H. Abreu, Rui Pereira, Isabel Sousa-Pinto, Eurico J. Cabrita, Cristina Delerue-Matos, and Maria Pilar Gonca̧lves. "Structural, Physical, and Chemical Modifications Induced by Microwave Heating on Native Agar-like Galactans." Jornal of Agricultural and Food Chemistry . 60 (2012): 4977-4985. Abstract

Native agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars’ structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-D-galactose (G) and 3,6-anhydro-α-L-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAEopt agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and Mv obtained for the MAEopt sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.

Guimarães, D., M. L. Carvalho, V. Geraldes, I. Rocha, and J. P. Santos. "Study of lead accumulation in bones of Wistar rats by X-ray fluorescence analysis: aging effect." Metallomics. 4 (2012): 66. AbstractWebsite

The accumulation of lead in several bones of Wistar rats with time was determined and compared Q3 for the different types of bones. Two groups were studied: a control group (n = 20), not exposed to lead and a contaminated group (n = 30), exposed to lead from birth, first indirectly through
mother’s milk, and then directly through a diet containing lead acetate in drinking water (0.2%). Rats age ranged from 1 to 11 months, with approximately 1 month intervals and each of the collections had 3 contaminated rats and 2 control rats. Iliac, femur, tibia–fibula and skull have been analysed by energy dispersive X-ray fluorescence technique (EDXRF). Samples of formaldehyde used to preserve the bone tissues were also analysed by Electrothermal Atomic Absorption (ETAAS), showing that there was no significant loss of lead from the tissue to the preservative. The bones mean lead concentration of exposed rats range from 100 to 300 mg g 1 while control rats never exceeded 10 mg g 1. Mean bone lead concentrations were compared and
the concentrations were higher in iliac, femur and tibia–fibula and after that skull. However, of all the concentrations in the different collections, only those in the skull were statistically Q4 significantly different (p o 0.05) from the other types of bones. Analysis of a radar chart also allowed us to say that these differences tend to diminish with age. The Spearman correlation test applied to mean lead concentrations showed strong and very strong positive correlations between
all different types of bones. This test also showed that mean lead concentrations in bones are negatively correlated with the age of the animals. This correlation is strong in iliac and femur and very strong in tibia–fibula and skull. It was also shown that the decrease of lead accumulation with age is made by three plateaus of accumulation,

da Silva, Mara Soares, Raquel Viveiros, Mónica B. Coelho, Ana Aguiar-Ricardo, and Teresa Casimiro. "Supercritical CO2-assisted preparation of a PMMA composite membrane for bisphenol A recognition in aqueous environment." Chemical Engineering Science. 68 (2012): 94-100. AbstractPDFWebsite

This work reports a novel strategy to prepare affinity composite membranes using supercritical fluid technology. By blending molecularly imprinted polymeric particles with PMMA, a porous hybrid structure with affinity to the template molecule, bisphenol A, was prepared using a supercritical carbon dioxide (scCO2)-assisted method. Membranes were characterized in terms of morphology, mechanical performance and transport properties. The ability of the polymers and hybrid membranes to adsorb bisphenol A was tested in aqueous solutions and fitted to a linearized Langmuir equation, showing that adsorption takes place at homogeneous affinity binding sites within the imprinted surface. Filtration experiments showed that the imprinted hybrid membrane was able to adsorb higher amounts of template even in non-equilibrium dynamic binding conditions. The hybridization of the PMMA membrane herein reported conveys two important improvements over neat PMMA membrane: it introduced molecular affinity towards the template molecule and significantly increased the permeability of the porous structures, which are key parameters in processes that involve membranes. This technique could expand the applications of polymeric beads powders and enhance the efficiency of the membrane's transport properties. Our work presents a new method to confer affinity to a porous structure by immobilization of imprinted polymers, combining polymer synthesis and membrane formation using supercritical fluid technology.

da Silva, Mara Soares, Raquel Viveiros, Ana Aguiar-Ricardo, Vasco D. B. Bonifacio, and Teresa Casimiro. "Supercritical fluid technology as a new strategy for the development of semi-covalent molecularly imprinted materials." RSC Adv.. 2 (2012): 5075-5079. AbstractPDFWebsite

Molecularly imprinted polymeric particles with molecular recognition towards Bisphenol A (BPA) were synthesized for the first time using the semi-covalent imprinting approach in supercritical carbon dioxide (scCO2). The material{'}s affinity to BPA was achieved by co-polymerizing ethylene glycol dimethacrylate (EGDMA) with a template-containing monomer{,} Bisphenol A dimethacrylate (BPADM) in scCO2. Bisphenol A is then cleaved from the polymeric matrix by hydrolysis with tetrabutylammonium hydroxide (n-Bu4OH) also in a supercritical environment{,} taking advantage of the high diffusivity of scCO2. The selectivity of the molecular imprinted polymer (MIP) was assessed by evaluating its capability to bind BPA in comparison with progesterone and [small alpha]-ethinylestradiol. In addition{,} the cross-linked particles were used to prepare a PMMA-based hybrid imprinted membrane by a scCO2-assisted phase inversion method. Results show that the incorporation of MIP particles was able to confer molecular affinity to BPA to the membrane and that at dynamic conditions of filtration{,} this imprinted porous structure was able to adsorb a higher amount of BPA than the corresponding non-imprinted hybrid membrane. Our work represents a valuable greener alternative to conventional methods{,} for the synthesis of affinity materials which are able to maintain molecular recognition properties in water.

Fino, M., and F. Coito. "Symbolic Characterization of VCOs and its application to optimization based design." Design of Analog Circuits Through Symbolic Analysis. Eds. M. FahkFahk, F. V. Fernandez, and E. Tlelo-Cuautle. Bentham Sciences Publishers Ltd, 2012. 399-412.
Martins, R. M. S., F. Beckmann, R. Castanhinha, O. Mateus, R. Araújo, and P. K. Pranzas Synchrotron radiation-based micro-computed tomography applied to the characterization of dinosaur fossils from the Lourinhã Formation. 1 st . Meeting of Synchrotron Radiation Users from Portugal. Caparica, Portugal, 2012.martins_et_al_2012_tomography_enurs_martins-rui_dinosaurfossils.pdf
Pinto, R. M., A. A. Dias, M. Coreano, M. de Simone, B. M. Giuliano, J. P. Santos, and M. L. Costa. "Tautomerism in 5-aminotetrazole investigated by core-level photoelectron spectroscopy and ΔSCF calculations." J. Electron. Spectrosc. Related Phenomena. 185 (2012): 13-17. AbstractWebsite

The C 1s and N 1s photoelectron spectra of gas-phase 5-aminotetrazole (5ATZ) were recorded using synchrotron radiation, with the aim of evaluating 1H/2H tautomer population ratios. The core-electron binding energies (CEBEs) were estimated from computational results, using the delta self-consistent-field (ΔSCF) approach. Simulated spectra were generated using these CEBEs and the results from Gaussian-n (Gn, n=1, 2 and 3) and Complete Basis Set (CBS-4M and CBS-Q) methods. Results reveal the almost exclusive predominance of the 2H-tautomer, with a 1H/2H ratio of ca. 0.12/0.88, taken from a gross analysis of the XPS C 1s spectrum, recorded at 365 K.

Martins, R. M. S., R. Araújo, O. Mateus, R. Castanhinha, P. K. Pranzas, and F. Beckmann. "Tomography applied to the study of dinosaur fossils from the collection of the museum of Lourinhã (Portugal)." I Congresso Internacional GeoCiencias na CPL. Coimbra: Univ. Coimbra, 2012. martins_et_al_2012_abstract.pdf
Cunha, Jácome, João P. Fernandes, Hugo Ribeiro, and João Saraiva. "Towards a Catalog of Spreadsheet Smells." Proceedings of the 12th International Conference on Computational Science and Its Applications - Volume Part IV. ICCSA'12. Berlin, Heidelberg: Springer-Verlag, 2012. 202-216. Abstracticcsa-sq12.pdf

Spreadsheets are considered to be the most widely used programming language in the world, and reports have shown that 90% of real-world spreadsheets contain errors. In this work, we try to identify spreadsheet smells, a concept adapted from software, which consists of a surface indication that usually corresponds to a deeper problem. Our smells have been integrated in a tool, and were computed for a large spreadsheet repository. Finally, the analysis of the results we obtained led to the refinement of our initial catalog.

Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, and João Saraiva. "Towards an Evaluation of Bidirectional Model-driven Spreadsheets." User evaluation for Software Engineering Researchers. USER' 12. ACM Digital Library, 2012. 25-28. Abstractuser12.pdf

Spreadsheets are widely recognized as popular programming systems with a huge number of spreadsheets being created every day. Also, spreadsheets are often used in the decision processes of profit-oriented companies. While this illustrates their practical importance, studies have shown that up to 90% of real-world spreadsheets contain errors. In order to improve the productivity of spreadsheet end-users, the software engineering community has proposed to employ model-driven approaches to spreadsheet development. In this paper we describe the evaluation of a bidirectional model-driven spreadsheet environment. In this environment, models and data instances are kept in conformity, even after an update on any of these artifacts. We describe the issues of an empirical study we plan to conduct, based on our previous experience with end-user studies. Our goal is to assess if this model-driven spreadsheet development framework does in fact contribute to improve the productivity of spreadsheet users.

Correia, Isabel, Teresa Melo, and Francisco Saldanha-da-Gama. "A two-echelon facility location problem with layout selection." Mathematics and Computers in Science and Engineering 3. 2012. Abstract

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Gião, R., V. Lúcio, C. Chastre, and A. Bras UFRG – Unidirectional fibre reinforced grout as strengthening material for reinforced concrete structures. BEFIB2012 – Fibre reinforced concrete. Guimarães: UMinho, 2012. Abstract

The present study is part of an extensive research project, where the main objective is to evaluate a strengthening solution for reinforced concrete structures using a small thickness jacketing in the compression side of the RC element with unidirectional fiber reinforced grout - UFRG.
For this purpose a high performance cementitious grout reinforced with continuous and unidirectional non woven fibermat has been developed. It was expected that the use of these type of fibers allowed an optimization of its percentage and orientation. It was expected that the use of these type of fibers allowed an optimization of its percentage and orientation. Besides, for continuous fibers (with an aspect ratio, defined as the length-to-diameter ratio, l/d=∞), the composite should attain higher tensile strength since the fiber embedment length is enough to prevent fiber pullout.
The experimental campaign included a set of preliminary tests that allowed the design of the fiber reinforced grout, sustained with rheological parameters [7] and mechanical characterization tests of the materials.
Finally, an experimental campaign was carried out in order to proceed to the mechanical characterization of the unidirectional fiber reinforced grout. Compressive tests were conducted in small thickness tubular specimens that enable the determination of the compressive strength and the static modulus of elasticity of the material. The tensile strength of the material was obtained using splitting tests of cubic specimens (according the standard DIN 1048-5). The experimental results are presented and analyzed.

Carvalho, T., V. Augusto, A. R. Brás, N. M. T. Lourenço, CAM Afonso, S. Barreiros, N. T. Correia, P. Vidinha, E. J. Cabrita, M. Dionísio, and B. Roling. "Understanding the Ion Jelly Conductivity Mechanism." Journal of Physical Chemistry B. 116 (2012): 2664-2676. Abstract

The properties of the light flexible device, ion jelly, which combines gelatin with an ionic liquid (IL) were recently reported being promising to develop safe and highly conductive electrolytes. This article aims for the understanding of the ion jelly conductive mechanism using dielectric relaxation spectroscopy (DRS) in the frequency range 10−1−106 Hz; the study was complemented with differential scanning calorimetry (DSC) and pulse field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. The room temperature ionic liquid 1-butyl-3-methylimmidazolium dicyanamide (BMIMDCA) used as received (1.9% w/w water content) and with 6.6% (w/w) of water content and two ion jellies with two different ratios BMIMDCA/gelatin/water % (w/w), IJ1 (41.1/46.7/12.2) and IJ3 (67.8/25.6/6.6), have been characterized. A glass transition was detected by DSC for all materials allowing for classifying them as glass formers. For the ionic liquid, it was observed that the glass transition temperature decreases with the increase of water content. While in subsequent calorimetric runs crystallization was observed for BMIMDCA with negligible water content, no crystallization was detected for any of the ion jelly materials upon themal cycling. To the dielectric spectra of all tested materials, both dipolar relaxation and conductivity contribute; at the lowest frequencies, electrode and interfacial polarization highly dominate. Conductivity, which manifests much more intensity relative to dipolar reorientations, strongly evidences subdiffusive ion dynamics at high frequencies. From dielectric measures, transport properties as mobility and diffusion coefficients were extracted. Data treatment was carried out in order to deconvolute the average diffusion coefficients estimated from dielectric data in its individual contributions of cations (D+) and anions (D−). The D+ values thus obtained for IJ3, the ion jelly with the highest IL/gelatin ratio, cover a large temperature range up to room temperature and revealed excellent agreement with direct measurements from PFG NMR, obeying to the same VFT equation. For BMIMDCA6.6%water, which has the same water amount as IJ3, the diffusion coefficients were only estimated from DRS measurements over a limited temperature range; however, a single VFT equation describes both DRS and PFG NMR data. Moreover, it was found that the diffusion coefficients and mobility are similar for the ionic liquid and IJ3, which points to a role of both water and gelatin weakening the contact ion pair, facilitating the translational motion of ions and promoting its dissociation; nevertheless, it is conceivable that a critical composition of gelatin that leads to those properties. The VFT temperature dependence observed for the conductivity was found to be determined by a similar dependence of the mobility. Both conductivity and segmental motion revealed to be correlated as inferred by the relatively low values of the decoupling indexes. The obtained results show that ion jelly could be in fact a very promising material to design novel electrolytes for different electrochemical devices, having a performance close to the IL but presenting an additional stability regarding electrical measurements and resistance against crystallization relative to the bulk ionic liquid.

Coito, Fernando, Helena Fino, and Pedro Pereira. "Variability-Aware Optimization of RF Integrated Inductors in Nanometer-Scale Technologies." Integrated Circuits for Analog Signal Processing. New York: Springer-Verlag , 2012.
Contreras, Javier, Luis Gomes, Sergej Filonovich, Nuno Correia, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "3D scanning characteristics of an amorphous silicon position sensitive detector array system." Optics express. 20.4 (2012): 4583-4602. Abstract
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Contreras, J.a, Gomes Filonovich Correia Fortunato Martins Ferreira L. b S. a. "3D scanning characteristics of an amorphous silicon position sensitive detector array system." Optics Express. 20 (2012): 4583-4602. AbstractWebsite

The 3D scanning electro-optical characteristics of a data acquisition prototype system integrating a 32 linear array of 1D amorphous silicon position sensitive detectors (PSD) were analyzed. The system was mounted on a platform for imaging 3D objects using the triangulation principle with a sheet-of-light laser. New obtained results reveal a minimum possible gap or simulated defect detection of approximately 350 μm. Furthermore, a first study of the angle for 3D scanning was also performed, allowing for a broad range of angles to be used in the process. The relationship between the scanning angle of the incident light onto the object and the image displacement distance on the sensor was determined for the first time in this system setup. Rendering of 3D object profiles was performed at a significantly higher number of frames than in the past and was possible for an incident light angle range of 15 ° to 85 °. © 2012 Optical Society of America.

Chumakov, Yu, S. - Y. Xiong, JR Santos, I. Ferreira, K. Termentzidis, A. Pokropivny, P. Cortona, and S. Volz. "Ab Initio Calculations and Measurements of Thermoelectric Properties of V2O5 Films." Journal of Electronic Materials (2012): 1-7. Abstract
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