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2012
Dimitrova, I., Vítor H. Fernandes, and J. Koppitz. "The maximal subsemigroups of semigroups of transformations preserving or reversing the orientation on a finite chain." Publicationes Mathematicae Debrecen. 81.1-2 (2012): 11-29.
Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, and João Saraiva. "MDSheet: A Framework for Model-driven Spreadsheet Engineering." Proceedings of the 34rd International Conference on Software Engineering. ICSE'12. ACM, 2012. 1395-1398. Abstracticse12_tooldemo.pdf

n this paper, we present MDSHEET, a framework for the embedding, evolution and inference of spreadsheet models. This framework offers a model-driven software development mechanism for spreadsheet users.

Martins, N., and M. Rebelo The method of fundamental solutions for elasticity problems with interfaces. Proceedings of 7th International Conference of the Croatian Society of Mechanics. Zadar, Croatia, 2012.
Ramos, Tania Rodrigues Pereira, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "Minimizing CO2 Emissions in a Recyclable Waste Collection System with Multiple Depots." EUROMA/POMS Joint Conference. 2012. 1-11. Abstracteuroma_2012_fullpaper_final.pdf

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Cunha, Jácome, João Saraiva, and Joost Visser. "Model-Based Programming Environments for Spreadsheets." Programming Languages. Eds. Francisco de Carvalho Junior, and Luis Barbosa. Vol. 7554. Lecture Notes in Computer Science, 7554. Springer Berlin / Heidelberg, 2012. 117-133. Abstractsblp12.pdf

Although spreadsheets can be seen as a flexible programming environment, they lack some of the concepts of regular programming languages, such as structured data types. This can lead the user to edit the spreadsheet in a wrong way and perhaps cause corrupt or redundant data. We devised a method for extraction of a relational model from a spreadsheet and the subsequent embedding of the model back into the spreadsheet to create a model-based spreadsheet programming environment. The extraction algorithm is specific for spreadsheets since it considers particularities such as layout and column arrangement. The extracted model is used to generate formulas and visual elements that are then embedded in the spreadsheet helping the user to edit data in a correct way. We present preliminary experimental results from applying our approach to a sample of spreadsheets from the EUSES Spreadsheet Corpus.

Cunha, Jácome Model-based Spreadsheet Engineering: Using Relational Models to Improve Spreadsheets. Eds. Shahanaz Soogah. LAP LAMBERT Academic Publishing, 2012. Abstractbook.pdf

Spreadsheets can be viewed as programming languages for non-professional programmers. These so-called ``end-user'' programmers vastly outnumber professional programmers creating millions of new spreadsheets every year. As a programming language, spreadsheets lack support for abstraction, testing, encapsulation, or structured programming. As a result, and as numerous studies have shown, the high rate of production is accompanied by an alarming high rate of errors. Some studies report that up to 90% of real-world spreadsheets contain errors. After their initial creation, many spreadsheets turn out to be used for storing and processing increasing amounts of data and supporting increasing numbers of users over long periods of time, making them complicated systems. An emerging solution to handle the complex and evolving software systems is Model-driven Engineering (MDE). To consider models as first class entities and any software artifact as a model or a model element is one of the basic principles of MDE. We adopted some techniques from MDE to solve spreadsheet problems. Most spreadsheets (if not all) lack a proper specification or a model. Using reverse engineering techniques we are able to derive various models from legacy spreadsheets. We use functional dependencies (a formalism that allow us to define how some column values depend on other column values) as building blocks for these models. Models can be used for several spreadsheet improvements, namely refactoring, safe evolution, migration or even generation of edit assistance. The techniques presented in this work are available under the framework HAEXCEL that we developed. It is composed of online and batch tools, reusable HASKELL libraries and OpenOffice.org extensions. A study with several end-users was organized to survey the impact of the techniques we designed. The results of this study indicate that the models can bring great benefits to spreadsheet engineering helping users to commit fewer errors and to work faster.

Monteiro, Rui, João Araújo, Vasco Amaral, Miguel Goulão, and Pedro Patrício. "Model-Driven Development for Requirements Engineering: The Case of Goal-Oriented Approaches." 8th International Conference on the Quality of Information and Communications Technology (QUATIC 2012). Eds. João Pascoal Faria, Ana Paiva, and Ricardo Machado. Lisbon, Portugal: IEEE CPS, 2012. Abstractquatic2012-full-crmg.pdf

Goal-Oriented Requirements Engineering (GORE) has received increasing attention over the past few years.
There are several goal-oriented approaches, each one using different kinds of models. We argue that it would be useful to relate them or even perform transformations among them automatically, in order to understand their similarities and differences, their advantages and disadvantages, allowing a possible migration or comparison between approaches. This is something that has not received enough attention. In this paper
we propose the definition and implementation of goal model transformations between i* and KAOS. As an immediate contribution, the approach can be used to migrate from one goal model to another through automatic model transformations. This approach also contributes to relate the concepts of i* and KAOS models and will help, for example, a development team in making the decision on which approach to follow, according to the nature of the project and the expressiveness of an approach to represent certain concepts
(e.g., obstacles are represented explicitly in KAOS, but not in i*). Another contribution is to facilitate communication among members of the same team, if they are specialized in different approaches.

Pina, João Murta, Pedro Pereira, Anabela Pronto, Pedro Arsénio, and Tiago Silva. "Modelling and Simulation of Inductive Fault Current Limiters." Physics Procedia. 36 (2012): 1248-1253. AbstractWebsite

Inductive superconducting fault current limiters have already demonstrated their technical viability in electrical networks. Its architecture and robustness make them potentially adequate for distribution networks, and this type of devices is considered as an enabling technology for the advent of embedded generation with renewable energy sources. In order to promote the growth and maturity of these superconducting technologies, fast design tools must be developed, allowing simulating devices with different materials in grids with diverse characteristics. This work presents advances in the development of such tool, which, at present stage, is an effective alternative to software simulations by finite elements methods, reducing dramatically computation time. The algorithms are now compared with experimental results from a laboratory scale prototype, showing the need to refine them.

Brazinha, C., A. P. Fonseca, H. Pereira, O. M. N. D. Teodoro, and J. G. C. Crespo. "Modelling gas permeation based on the morphology of a natural polymer material." Procedia Engineering. Vol. 44. 2012. 529-531. Abstract2012_modelling_gas_permeation.pdf

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Carvalho, Helena Modelling resilience in supply chain. Universidade Nova de Lisboa. Lisbon: Universidade Nova de Lisboa, 2012.phd_hmlc.pdf
Ludovico-Marques, Marco, Carlos Chastre, and Graça Vasconcelos. "Modelling the compressive mechanical behaviour of granite and sandstone historical building stones." Construction and Building Materials. 28 (2012): 372-381. AbstractWebsite

Building stones, particularly sandstone and granite, are very important in the building elements of Portugal’s historical and cultural heritage. Experimental research, based on uniaxial compressive tests, was carried out on selected representative samples of lithotypes of rocks used in historic built heritage, with a view to evaluating the compressive mechanical behaviour of different building stones. The results showed that porosity plays a central role in the compressive behaviour of granites and sandstones. As porosity can be evaluated in field conditions with non-destructive tests it was decided to derive an analytical model to predict compressive behaviour based on the knowledge of porosity of the building stones. A cubic polynomial function was adopted to describe the pre-peak regime under compression to implement the model. Furthermore, a statistical correlation between mechanical and porosity data had to be defined. Good agreement between experimental and analytical compressive stress–strain diagrams, from which the mechanical properties like compressive strength and modulus of elasticity can be derived, was achieved.

Rocha, H., and I. Oitavem. "A mudança que abala o mundo – Editorial." Educação e Matemática.116 (2012): 1.
Rodrigues, Paula, Carlota Rebelo, and Gabriela M. M. Gomes Multi-scale models for drug resistant tuberculosis. International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2012. La Manga, Murcia, Spain, 2012.
Aelenei, L., J. Ayoub, and D. Aelenei. "Net Zero Residential Building Case Studies - ECBCS - SHC Joint Project Update: Annex 52- Task 40." IEA ECBCS news. 56 (2012): 10-12. AbstractWebsite

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Mateus, O. "New dinosaur and pterosaur tracksites from the Late Jurassic of Portugal." Chongqing, China: 2012 Abstract Book of Qijiang International Dinosaur Tracks Symposium, 2012. Abstractmateus_2012_dinosaur_tracks_portugal__abstract_book_qijiang_int_dinosaur_tracks_symposium.pdf

Portugal is rich on dinosaur remains (bones, eggs, and tracks) from Early Jurassic to Late
Cretaceous ages, but mainly from the Late Jurassic, in which dozen of tracksites have been reported.
Here are reported new or poorly known track localities:
1) Five tracksites share the preservation substrate (marine carbonated limestone), age (late Jurassic), geographic area (Leiria district of Portugal), kind of preservation (true tracks), and completeness (trackways of multiple individuals):
i) Praia dos Salgados includes eight trackways, mostly ornithopods and theropods, and one wide gauge sauropod, made in very soft sediment; some preserve the hallux impression.
ii) Serra de Mangues is mostly covered with vegetation but seems to include dozens of tracks comprising theropods, thyreophorans, ornithopods and sauropods.
iii) Sobral da Lagoa (Pedreira do Rio Real) include six trackways but poorly preserved;
and
iv) Serra de Bouro that preserves four sauropod trackways in one single layer.
v) Pedrógão, preserved, at least, one theropod trackway and several isolated tracks of
theropods and ornithopods were found in different layers in the Early Oxfordian.
2) The locality in Praia de Porto das Barcas yielded natural casts of stegosaur tracks
(including pes print with skin impression) and a very large sauropod pes print with about
1.2 m long pes.
3) A new pterosaur tracksite was found in the Late Jurassic of Peralta, Lourinhã (Sobral Member, Lourinhã Fm.; Late Kimmeridgian/Early Tithonian). More than 220 manus and pes tracks have been collected in about five square meters, all ascribed to pterosaurs. The tracks were produced in a thin mud layer that has been covered by sand which preserved them as sandstone mould infill (natural casts). The manus of the largest specimens is 13 cm wide and 5.5 cm long and the pes measures 14.5 cm in length and 9 cm in width. This shows the occurrence of very large pterosaurs in the Late Jurassic. Other pterosaur tracksites in the Late Jurassic of Portugal are: Porto das Barcas (Lourinhã Municipality), South of Consolação (Peniche Municipality), and Zambujal de Baixo (Sesimbra Municipality).

Vineyard, D., O. Mateus, LL Jacobs, M. J. Polcyn, and A. Schulp. "A new marine turtle from the Maastrichtian of Angola." Journal of Vertebrate Paleontology, Program and Abstracts, 2012, 189. ISSN 1937-2809 (2012): 189.vineyard_mateus_et_al_2012_euclastes_chelonia_turtle_angola_svp_2012_abstract.pdf
Mouquinho, AI, K. T. Petrova, M. T. Barros, and J. C. Sotomayor. "New Polymer Networks for PDLC Films Application." New Polymers for Special Applications . Ed. A. De-Souza-Gomes. Rijeka: InTech, 2012. 139-164.
Morgado, M. L., N. J. Ford, and M. Rebelo A non-polynomial collocation method for fractional terminal value problems. AIP Conference Proceedings- ICNAAM 2012, Vol. 1479,. Kos, Greece, 2012.
Hendrickx, C., R. Araújo, and O. Mateus. "The nonavian theropod quadrate: systematics usefulness, major trends and phylogenetic morphometrics analysis." Journal of Vertebrate Paleontology, Program and Abstracts, 2012, p.110. ISSN 1937-2809 , 2012. Abstracthendrickx_araujo__mateus_2012_quadrate_theropods_svp_2012_abstract_book_meeting_abstracts.pdf.pdf

The quadrate in nonavian theropods is incredibly diverse morphologically; however this morphological disparity has been underestimated for taxonomic purposes. The quadrate topological homologies and anatomy, as well as the terminology, among nonavian theropod clades are reviewed. In order to evaluate the phylogenetic potential and investigate the evolutionary transformations of the quadrate, we conducted a Catalano-Goloboff phylogenetic morphometric analysis using 3 morphometric characters, a total of 28 landmarks coded for 23 taxa, as well as a cladistic analysis using 115 discrete quadrate-related characters coded for 43 taxa. The cladistic analysis provides a fully resolved tree mirroring the current classification of nonavian theropods. The quadrate morphology by its own provides a wealth of data with strong phylogenetic signal. Several unambiguous synapomorphies support nonavian theropod relationships and the resulting consensus tree allows inference of major trends in the evolution of this bone. Important synapomorphies include: for Abelisauridae, a lateral ramus extending to the ectocondyle; for Tetanurae, the absence of the lateral process; for Spinosauridae, a medial curvature of the ventral part of the pterygoid ramus occurring just above the mandibular articulation; for Neotetanurae, an anterior margin of the pterygoid flange formed by a roughly parabolic margin; and for Tyrannosauroidea, a semi-oval pterygoid flange shape in medial view. The Catalano-Goloboff phylogenetic morphometric analysis reveals two main morphotypes of the mandibular articulation of the quadrate linked to function. The first morphotype, characterized by an anteroposteriorly broad mandibular articulation with two ovoid/subcircular condyles roughly subequal in size, is found in Ceratosauria, Tyrannosauroidea and Oviraptorosauria. This morphotype allows a very weak displacement of the mandible laterally. The second morphotype is characterized by an elongate and anteroposteriorly narrow mandibular articulation and a long and parabolic/sigmoid ectocondyle. Present in Megalosauroidea, Allosauroidea and Dromaeosauridae, this morphotype permits the lower jaw rami to be displaced laterally when the mouth opened.

Vicente da Silva, M., and A. N. Antão. "A novel augmented Lagrangian based formulation for upper bound limit analysis." International Journal for Numerical Methods in Engineering. vol. 89.nº 12 (2012): pp. 1471-1496. Abstract

This paper describes a novel upper-bound formulation of limit analysis. This formulation is an innovative variant of an existing two-field mixed formulation based on the augmented Lagrangian method also developed by the authors. A natural approach is used to describe the deformation of each finite element. Furthermore, and in contrast to the previous formulation, two independent field approximations are now both used to define the velocity field, defined globally and at element level. It is shown that this feature allows a governing system of uncoupled linear equations to be obtained. Some numerical examples in plane strain conditions are presented in order to illustrate the current model performance. In conclusion, the potential and advantages of this new approach are discussed.

Vicente da Silva, M., and A. N. Antão. "A novel augmented Lagrangian-based formulation for upper-bound limit analysis." International Journal For Numerical Methods in Engineering. 89.12 (2012): 1471-1496. Abstract

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Palma, M. L., and J. P. Santos. "Nuclear spin–spin constants, rotational g factor and susceptibility of sulphur hexafluoride." Mol. Phys.. 110 (2012): 2163. AbstractWebsite

Following our previous study on spin–rotation and shielding constants of the SF6 molecule, the rotational g factor and the magnetic susceptibility are calculated here, using ab initio methods to evaluate the electronic contribution to the nuclear hyperfine constants, and compared with experimental results. It is shown, for the first time, that the electronic component of the rotational g factor is proportional to a constant, which is given by a sum over electronic states. We also evaluate for the SF6 molecule the indirect, or electron-coupled spin–spin interaction, theoretically described by Ramsey, and show that it gives non-negligible corrections to direct coupling constants d1 and d2. The contributions of the terms included in this interaction (DSO, PSO, SD and FC) are also analysed.

Rocha, H. O recurso a diferentes representações no ensino das funções com o apoio da tecnologia. Actas do XXIII SIEM – Seminário de Investigação em Educação Matemática. Coimbra, Portugal: APM, 2012.
Rodríguez-Martínez, E. V., A. D. Egídio dos Reis, and R. M. R. Cardoso. "On the Erlang(n) dual risk model and dividends problems." STIN Colloquium 2012. Mexico City 2012.
Hendrickx, C., and O. Mateus. "Ontogenetical changes in the quadrate of basal tetanurans." 10 th Annual Meeting of the European Association of Vertebrate Paleontologist ¡Fundamental! . 20 (2012): 101-104. Abstracthendrickx__mateus_2012_ontogenetical_changes_in_the_quadrate.pdf

Although nonavian theropod have received considerable interest in the last years, their ontogeny still remains poorly understood, especially the ontogenetical changes affecting their skull (Rauhut
and Fechner, 2005). The quadrate, for instance, is preserved in several embryos and juvenile specimens belonging to many clades of theropods such as the Tyrannosauridae (Carr, 1999), Compsognathidae (Dal Sasso and Maganuco, 2011), Therizinosauroidea (Kúndrat et al., 2007), Oviraptoridae (Norell et al., 1994; Norell et al., 2001; Weishampel et al., 2008) and Troodontidae (Varrichio et al., 2002) but very little is usually said about the anatomy of this bone and no one has ever investigated ontogenetical variation in the nonavian theropod quadrate. The discovery of two quadrates belonging to embryos of the sinraptorid Lourinhanosaurus antunesi from Portugal and five isolated quadrates pertaining to juvenile, subadult and adult specimens of Spinosauridae from Morocco fills this gap and allows some ontogenetic information to be drawn for this bone in these two specific clades of Theropoda.
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