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Publications

Publications by CRIIS

2013

State Operation Optimization in Electrical Networks

Authors
Pereira, P; Leitao, S; Solteiro Pires, EJS;

Publication
2013 1ST BRICS COUNTRIES CONGRESS ON COMPUTATIONAL INTELLIGENCE AND 11TH BRAZILIAN CONGRESS ON COMPUTATIONAL INTELLIGENCE (BRICS-CCI & CBIC)

Abstract
This paper makes a study about optimal supply of the energy service, using simulations of network operation scenarios, in order to optimize resources and minimize the variables: operation cost, energy losses, generation cost and consumers shedding. These simulations create optimal operation models of the network, allowing the system operator obtain knowledge to take pre-established procedures that must be performed in situations of contingency in order to forecast and minimize drawbacks. The simulations were performed using a multiobjective particle swarm optimization algorithm. The algorithm was applied to the IEEE 14 Bus network where the optimal power flow was evaluated by MATPOWER tool to establish an optimal electrical working model to minimize the associated costs.

2013

Single-objective spreading algorithm

Authors
Pires, EJS; Mendes, L; Lopes, AM; de Moura Oliveira, PB; Machado, JAT;

Publication
Intelligent Systems, Control and Automation: Science and Engineering

Abstract
This paper addresses the problem of finding several different solutions with the same optimum performance in single objective real-world engineering problems. In this paper a parallel robot design is proposed. Thereby, this paper presents a genetic algorithm to optimize uni-objective problems with an infinite number of optimal solutions. The algorithm uses the maximin concept and e-dominance to promote diversity over the admissible space. The performance of the proposed algorithm is analyzed with three well-known test functions and a function obtained from practical real-world engineering optimization problems. A spreading analysis is performed showing that the solutions drawn by the algorithm are well dispersed. © 2013, Springer Science+Business Media Dordrecht.

2013

The viStaMPS tool for visualization and manipulation of time series interferometric results

Authors
Sousa, JJ; Magalhaes, LG; Ruiz, AM; Sousa, AMR; Cardoso, G;

Publication
COMPUTERS & GEOSCIENCES

Abstract
In the last decade, Synthetic Aperture Radar Interferometry (InSAR) has become operational as a technique that allows remote detection of deformation at the Earth's surface. Analysis of time series of SAR images extends the area where InSAR can be successfully applied and also permits detection of smaller displacements through the reduction of error sources. Stanford Method for Persistent Scatterers (StaMPS) InSAR implementation, which is based on the processing of multi-temporal SAR data, is widely used for ground deformation monitoring. This is due mainly to its proven reliability and freeware distribution among the scientific community. However, some issues can make the interpretation of the results a difficult task: StaMPS supports data processing based on command prompt, which increases the difficulty of usage by users not familiar with the specific programming language that supports StaMPS. Moreover, several visualization tasks are not implemented in the standard approach requiring that each user develop its own code for visualization and interpretation purposes. In this paper, we present viStaMPS, a new visual application developed to enhance the visualization, manipulation and exportation of StaMPS results. The programmed application is developed in Matlab through the Graphical User Interface (GUI) and no coding is required for running it, which avoids any programming language knowledge for standard uses. The included graphical interface is very versatile allowing the user to choose among several features: visualization, manipulation and exportation of data which are not available in the original StaMPS.

2013

On analyzing the semantics of IEC61131 -3 ST and IL applications

Authors
de Sousa, M;

Publication
Lecture Notes in Mechanical Engineering

Abstract
The IEC 61508 standard recognizes the programming languages defined in IEC 61131-3 as being appropriate for safety-related applications, and suggests the use of static analysis techniques to find errors in the source code. In this context, we have added a semantic verification stage to the MatIEC compiler—an open source ST, IL, and SFC code translator to ANSI C. In so doing, we have identified several issues related to the definition of the semantics of the IL and ST programming languages, as well as with the data type model defined in IEC 61131-3. Most of the issues are related to undefined semantics, which may result in applications generating distinct results, depending on the platform on which they are executed. In this paper we describe some of the issues we uncovered, explain the options we took, and suggest how the IEC 61131-3 standard could be made more explicit. © Springer International Publishing Switzerland 2013.

2013

Protective Activity of Hydroxytyrosol Metabolites on Erythrocyte Oxidative-Induced Hemolysis

Authors
Paiva Martins, F; Silva, A; Almeida, V; Carvalheira, M; Serra, C; Rodrigues Borges, JE; Fernandes, J; Belo, L; Santos Silva, A;

Publication
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

Abstract
The capacity of important hydroxytyrosol metabolites (homovanillyl alcohol, hydroxytyrosol acetate, homovanillyl alcohol acetate, hydroxytyrosol 3' and 4'-O-glucuronides, and homovanillyl alcohol 4'-O-glucuronide) to protect red blood cells (RBCs) from oxidative injury induced by the radical initiator 2,2'-azo-bis(2-amidinopropane) dihydrochloride (AAPH) or by the natural radical initiator H2O2 was evaluated. In the presence of AAPH, all compounds showed to protect RBCs from hemolysis in a dose-dependent manner, exccept for the homovanillyl alcohol glucuronide, with the order of activity being at 20 mu M hydroxytyrosol > hydroxytyrosol glucuronides = hydroxytyrosol acetate = homovanillyl alcohol = homovanillyl acetate > homovanillyl alcohol glucuronide. At 10 mu M, hydroxytyrosol, hydroxytyrosol acetate, and hydroxytyrosol glucuronides still protected hemoglobine from oxidation and from morphological RBC changes. In the presence of H2O2, hydroxytyrosol showed to significantly protect RBCs from oxidative hemolysis in a dose-dependent manner, but the hydroxytyrosol glucuronides showed only a limited protection that was independent of the concentration used.

2013

Project Management Success I-C-E Model – A Work in Progress

Authors
Marques, A; Varajão, J; Sousa, J; Peres, E;

Publication
Procedia Technology

Abstract
Project management in software development has shown high rates of failure since the beginning of computation. Over the last years, several studies have sought and proposed solutions for this problem by focusing, for instance, on success critical aspects and evaluation criteria. Although these efforts have provided a significant evolution in how the work is done, project management success rates are in fact still well below the desirable values. This paper presents a work-inprogress based on an integrated approach to project management success and proposes a model that considers jointly the set of success influencers, project characteristics and evaluation criteria of success, from the initiation of a project until its closure.

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