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Pinto P.L.,University of Lisbon | Mendes C.,INOV Inesc Inovacao | Caetano A.,University of Lisbon | Da Silva M.M.,University of Lisbon
Proceedings of the ACM Symposium on Applied Computing | Year: 2015

The development of information technologies (IT) has increased the number of IT dependent business processes within organisations, enforcing the crucial role of IT in today's enterprise implementations. In spite of IT advances, human beings still constitute the most valuable asset of any enterprise and the cooperation between them is indispensable for the operation of business processes. Traditional business process modelling techniques have limitations regarding the acquisition process which is time-consuming and do not take fully advantage of IT to represent updated process models. Besides, these techniques are limited concerning the analysis and improvement of the resulting models. This paper proposes a method to analyse updated business processes in terms of the collaboration between the participant actor roles, taking into account the importance of IT and human beings at those processes. The method receives as input event logs extracted from the application and technological infrastructure that supports the business processes and combines techniques from both Process Mining and the Ψ-theory to analyse enterprise ontology models against the mined processes, detecting opportunities for business process reengineering. The method was applied to analyse a VPN access approval process within a national defence governmental institution. The evaluation was performed using the Osterle principles. Copyright 2015 ACM. Source

Utkin A.B.,INOV Inesc Inovacao | Utkin A.B.,University of Lisbon
Wave Motion | Year: 2012

The method of incomplete separation of variables is applied for solving the wave propagation problems in which the source distribution and the emanated wave are constrained by an elliptic cylinder. Solutions are obtained in the form of expansions in terms of the Mathieu modes, whose completeness makes possible to solve the problem for arbitrary source distribution and initial values of the wavefunction and its time derivative defined within the cylinder. Transient modal amplitudes are found using the Riemann (Riemann-Volterra) method. An important feature of this approach is the straightforward definition of the essentially bounded effective integration areas on the plane spanned by the longitudinal and time coordinates, taking into account the spatiotemporal constraints imposed on the source. For source turned on in a fixed instant, the method is capable to model wave propagation inside the semi-infinite and finite elliptic cylinders provided that the Dirichlet or Neumann boundary conditions are specified on the limiting cross-section(s). Recent techniques of transverse-longitudinal wave decomposition open the prospect of adapting the method to more general cylindrical configurations and to other cases, in which the incomplete separation of variables results in partial differential equations of a known Riemann function (such as the Euler-Poisson-Darboux equation). © 2011 Elsevier B.V. Source

Utkin A.B.,INOV Inesc Inovacao
Proceedings of the International Conference Days on Diffraction, DD 2010 | Year: 2010

The Cauchy problem for the inhomogeneous wave equation is solved for the case in which both the source and the emanated wave are constrained by an elliptical cylinder. The solution is obtained in the elliptic cylindrical coordinates using an expansion in terms of the elliptic-membrane vibration modes and the Riemann method. © 2010 Days on Diffraction. Source

Gameiro C.,University of Lisbon | Utkin A.B.,INOV Inesc Inovacao | Utkin A.B.,University of Lisbon | Cartaxana P.,Copenhagen University | And 2 more authors.
Agricultural Water Management | Year: 2016

Chlorophyll fluorescence measurements have been widely applied as non-destructive methods to study the photosynthetic efficiency of plants, under control or stress conditions. Compared to most protocols of pulse amplitude modulation (PAM) fluorometry, laser induced chlorophyll fluorescence (LIF) has the advantages of not requiring pulses to be delivered at close range, allowing the remote analysis of a great number of individual plants in a short period of time. Such analyses are extremely useful, for instance, when doing large phenotyping screens of Arabidopsis thaliana mutants or ecotypes. Water deficit is a major abiotic stress compromising plant growth and productivity. Arabidopsis has been adopted as the main model organism in plant sciences and it has been widely used in plant stress studies. However, reports on the applications of LIF techniques to this model plant are scarce. Here we report the use of LIF to investigate changes in chlorophyll a (Chl a) fluorescence signature under progressive drought of potted Arabidopsis plants (Slow Stress) and under fast dehydration of detached leaves (Fast Stress). Results show that the two dehydration methods cause distinct modifications on the red/far-red Chl a fluorescence ratio (F690/F730) and on the wavelengths of Chl a fluorescence maxima. These differences are likely related to distinct changes in water content, photosynthetic pigments, anthocyanins, fatty acid composition and other metabolic adaptations, which are differently regulated in Slow and Fast Stress. Of particular interest are Chl a emission fluorescence changes, which take place under progressive drought, before a substantial decrease in leaf water content. Additionally, no differences were found on LIF emission spectra between fully expanded and young leaves. However, the choice of leaf surface influenced fluorescence emission, with the abaxial surface displaying lower fluorescence and higher F690/F730 ratios. Results suggest that LIF is a fast and non-destructive tool suitable for high-throughput phenotyping of Arabidopsis under water deficit. © 2015 Elsevier B.V. Source

Silva N.,University of Lisbon | Tribolet J.,University of Lisbon | Da Silva M.M.,University of Lisbon | Mendes C.,INOV Inesc Inovacao
IC3K 2015 - Proceedings of the 7th International Joint Conference on Knowledge Discovery, Knowledge Engineering and Knowledge Management | Year: 2015

A metamodel is an important aspect of defining a modeling language. It specifies the language's syntax through a set of constructs as well as how the language models are ought to be composed. Modeling languages, and thus their metamodels, are subject of constant evolution due to changing language requirements as consequence of business changes. Therefore, perceiving the essential aspects responsible for altering the structure of metamodels when a change requirement arises can become an issue. The Enterprise Ontology theory and its methodology (DEMO) provide ontological knowledge about organizations resulting in organizational self-awareness. Applying this methodology to the context of metamodeling can be a starting point for uncovering the essential aspects, i.e., the ontological knowledge regarding metamodel evolution. For that purpose, we modeled two diagrams using the DEMO methodology. The input for both diagrams was a set of coupled operations defined in Herrmannsdörfer's evolutionary metamodeling research. In the end we stated the main conclusions of our work and themes for future work. Copyright © 2015 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved. Source

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