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Publications

2015

Fracture behaviour of wood bonded joints under modes i and II by digital image correlation and fibre Bragg grating sensors

Authors
Xavier, J; Fernandes, JRA; Morais, JJL; Frazão, O;

Publication
Ciencia e Tecnologia dos Materiais

Abstract
Direct identification of cohesive laws in modes I and II of wood bonded joints is addressed by the double cantilever beam (DCB) and end-notched flexure (ENF) tests, respectively. Moreover, the development and extension of fracture process zone (FPZ) ahead of the initial crack tip, is analysed by means of digital image correlation (DIC) and embedded fibre Bragg grating (FBG) sensors. From FBG spectral response, the spectrum geometric mean is determined and the strain induced by wavelength variation employed to identify the initial and final stages of the FPZ. These stages are used to consistently define the cohesive laws in both modes I and II. Resistance-curves are determined from the compliance-based beam method (CBBM). Besides, the crack tip opening displacements (CTOD) are determined by post-processing displacement field provided by DIC around the initial crack tip. The strain energy release rate as a function of the CTOD are then determined for both mode I and mode II. The respective cohesive laws are reconstructed by numerical approximation and differentiation. It is concluded that the proposed data reduction scheme is effective to determine both the FPZ development phase and the corresponding cohesive laws of wood bonded joints in both mode I and mode II.

2015

The Usefulness of State Trade Missions for the Internationalization of Firms: An Econometric Analysis

Authors
Teixeira, AAC; Caiado, A; Africano, AP;

Publication
HAGUE JOURNAL OF DIPLOMACY

Abstract
Empirical studies are scarce on the usefulness of state trade missions as a way to promote the internationalization of firms. The results of applying an econometric model - involving 136 participations in twelve state trade missions that occurred between 2005 and 2008 - indicate that a company's size, foreign capital, export intensity, innovation intensity and experience in the market visited are relevant variables in an assessment of the results of state trade missions. Investment in the simple organization of trade state missions is not enough. It is necessary to select the most competent companies and to add more structured programmes to the organization of a mission in order to create and improve firms' competences.

2015

Incorporating regulator requirements in reliability analysis of smart grids. Part 2: Scenarios and results

Authors
Ridzuan M.I.M.; Hernando-Gil I.; Djokic S.; Langella R.; Testa A.;

Publication
IEEE PES Innovative Smart Grid Technologies Conference Europe

Abstract
This is the second paper in a two-part series discussing how Regulator requirements for continuity of supply could be incorporated in the reliability analysis of existing electricity networks and future 'smart grids'. Part 1 paper presents input data, parameters and models required for a comprehensive assessment of system reliability performance, including an overview of the overall and guaranteed standards of performance in the UK and Italy. This paper presents scenarios and results of both analytical and probabilistic reliability assessment procedures for the test network introduced in Part 1 paper.

2015

Demonstration of Realistic Multi-agent Scenario Generator for Electricity Markets Simulation

Authors
Silva, F; Teixeira, B; Pinto, T; Santos, G; Praca, I; Vale, Z;

Publication
ADVANCES IN PRACTICAL APPLICATIONS OF AGENTS, MULTI-AGENT SYSTEMS, AND SUSTAINABILITY

Abstract

2015

Impacts of Participating in Different Demand Response Programs on Operational Behavior of Plug-in Electric Vehicle Parking Lots

Authors
Shafie khah, M; Gil, FAS; Catalao, JPS; Aghaei, J; Barani, M;

Publication
2015 International Symposium on Smart Electric Distribution Systems and Technologies (EDST)

Abstract
With increasing environmental concerns, the electrification of transportation plays an outstanding role in the sustainable development. In this context, plug-in electric vehicle and demand response have indispensable impacts on future smart grid. Since integration of electric vehicles into the grid is a key element to achieve sustainable energy systems, this paper studies the behavior of plug-in electric vehicle parking lots in the electricity markets. Participation of these new market players, as responsive demands, is modeled in both price-based and incentive-based demand response programs. Moreover, impacts of different demand response programs on optimal operational behavior of the parking lots are investigated. In addition to uncertainties of activated reserve, uncertainties of electric vehicle class, arrival and departure times, and initial battery state-of-charge are also considered. Stochastic programming is used to address the mentioned uncertainties. Numerical studies indicate that the participation of parking lots in different demand response programs can increase their profit.

2015

ORCHESTRATING ONLINE GROUP WORK WHILE ASSESSING INDIVIDUAL PARTICIPATIONS

Authors
Figueira, A;

Publication
INTED2015: 9TH INTERNATIONAL TECHNOLOGY, EDUCATION AND DEVELOPMENT CONFERENCE

Abstract
Group work is an essential activity during both graduate and undergraduate formation. During group work Students develop a set of skills, and employ criticism which helps them to better handle future interpersonal situations. Although there is a vast theoretical literature and numerous case studies about group work, we haven't yet seen much development concerning the assessment of individual group participants. The problem relies on the difficulty to have the perception of each student contribution to the whole work. Nevertheless, more than frequently, the assessment of the group is transposed to each group participant, which in turn results in each student having the same final mark. We propose and describe a novel tool to manage and assess individual group work taking into account the amount of work, interaction, quality, and the temporal evolution of each group participant. The module features the possibility to predict the final activity grading, based on the interaction patterns and automatic comparison with former interaction patterns. We describe the conceptual design of our tool and present its two operating modes of the module. We then describe the methodology for the assessment in the two operating modes and how the tool collects data from interactions to predict final grading.

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