A model for information retrieval driven by conceptual spaces

A retrieval model describes the transformation of a query into a set of documents. The question is: what drives this transformation? For semantic information retrieval type of models this transformation is driven by the content and structure of the semantic models. In this case, Knowledge Organization Systems (KOSs) are the semantic models that encode the meaning employed for monolingual and cross-language retrieval. The focus of this research is the relationship between these meanings’ representations and their role and potential in augmenting existing retrieval models effectiveness. The proposed approach is unique in explicitly interpreting a semantic reference as a pointer to a concept in the semantic model that activates all its linked neighboring concepts. It is in fact the formalization of the information retrieval model and the integration of knowledge resources from the Linguistic Linked Open Data cloud that is distinctive from other approaches. The preprocessing of the semantic model using Formal Concept Analysis enables the extraction of conceptual spaces (formal contexts)that are based on sub-graphs from the original structure of the semantic model. The types of conceptual spaces built in this case are limited by the KOSs structural relations relevant to retrieval: exact match, broader, narrower, and related. They capture the definitional and relational aspects of the concepts in the semantic model. Also, each formal context is assigned an operational role in the flow of processes of the retrieval system enabling a clear path towards the implementations of monolingual and cross-lingual systems. By following this model’s theoretical description in constructing a retrieval system, evaluation results have shown statistically significant results in both monolingual and bilingual settings when no methods for query expansion were used. The test suite was run on the Cross-Language Evaluation Forum Domain Specific 2004-2006 collection with additional extensions to match the specifics of this model.

Marginal Activity Access Cost (MAAC): a new indicator for sustainable Land Use/Transport (LUT) planning

The paper presents the ‘Marginal Activity Access Cost’, an accessibility indicator providing estimation in monetary terms of the impacts on mobility and on the environment of locating a single new activity in a specific zone of the urban area. In the first part of this paper, the new indicator is presented and compared to other accessibility indicators proposed in literature. In the second part, the MAAC is validated through an application to the urban area of Rome. The paper concludes with brief remarks on using the proposed accessibility indicator as index of performance for sustainable spatial planning.

The new suburban history, New Urbanism and the spaces in between

A review article of three recent books on suburbanization and suburbia in the USA: Andrew Friedman, Covert Capital: Landscapes of Denial and the Making of the US Empire in the Suburbs of Northern Virginia. Berkeley, Los Angeles: University of California Press, 2013. 416pp. £19.95 pbk. Elaine Lewinnek, The Working Man's Reward: Chicago's Early Suburbs and the Roots of American Sprawl. Oxford and New York: Oxford University Press, 2014. 239pp. 20 b&w illustrations. £30.99 hbk. Benjamin Ross, Dead End: Suburban Sprawl and the Rebirth of American Urbanism. Oxford and New York: Oxford University Press, 2014. 249pp. £20.99 hbk.

The stamp of identities: negotiating diasporic Chinese subjectivity in philatelic spaces

This paper examines the politics and poetics of identity construction and articulation among guiqiao (Returned Overseas Chinese) through a case study of a postage stamp exhibition put up jointly by an ordinary guiqiao and an official huaqiao (Overseas Chinese) museum in Quanzhou, China. Two conflicting meaning systems are identified in this exhibition. On the surface and mainly through words, it promulgates a highly clichéd China-centred discourse of huaqiao as patriotic subjects, legitimated by the authority of an official museum. Simultaneously, it articulates implicitly a “trans-local diasporic subjectivity” conveyed by the imagery of stamps and constituted by constant interactions between the materiality of stamps and the bodily experience of stamp collectors beyond the museum. This study contributes to the study of guiqiao, and of Chinese diaspora in general, in two ways. First, it complicates the conventional understanding of guiqiao identity by pinpointing contested negotiations between the state from above and guiqiao from below, involving simultaneously conflicts and compromises. Secondly, it brings to light the important role of body, affect and materiality in the construction and articulation of guiqiao identities, paving the way for integrating museum and migration studies with the potential to re-conceptualize transnational mobilities in the Chinese context and beyond.

Eco-cities: technological showcases or public spaces?

A growing body of critical literature seeks to identify conceptual and practical problems accompanying the realisation of mainstream ‘eco-city’ initiatives around the world. However, little attention has been paid to the status of the ‘city’ itself within the broader discourse. If eco-cities are to be more than experimental ‘technological showcases’, and aim to transform urban life more generally, the question of what types of ‘cityness’ will ensue is of considerable importance. To effect a more significant sustainability transition, eco-city plans and policies may need somehow to encompass a more nuanced conceptualisation of cities as complex, unpredictable, and emergent spaces. The incompatibility of such a conceptualisation with liberal-modernist modes of planning means that radically innovative new approaches to eco-city development may need to be found. This thesis considers whether the eco-city, theorised as a multiple process of real-world experimentation, may shed some light on how ‘cityness’ might better be planned for in future. To do so, it conceptualises cityness through the lens of ‘publicness’. It makes an original contribution to knowledge by developing a new theoretical model of publicness as an ‘assemblage’ of space and behaviour, with an ‘emergent’ and ‘civic’ modality. It thereby extends recent debates over the idea of ‘urban assemblage’, and makes innovative links between theories of planning and of the public. This model informs the analysis of original empirical research, investigating the conceptualisation of the public in an international sample of official eco-city documents, and exploring the publicness of two implemented initiatives, in Portland, Oregon (US) and newly built Sejong City (South Korea). The research finds that publicness tends to be poorly articulated in mainstream eco-city plans and policies, with potentially negative implications for sustainability in the ‘urban age’. However, it also argues that state institution-led planning – even when experimental ‘governance’ approaches are adopted – may inevitably be limited in its ability to encompass the emergent public life of the city. The thesis concludes by considering the prospects for overcoming or more productively acknowledging these limits in future.

Virtual power players demand response programs management based on locational marginal prices

Power systems have been suffering huge changes mainly due to the substantial increase of distributed generation and to the operation in competitive environments. Virtual power players can aggregate a diversity of players, namely generators and consumers, and a diversity of energy resources, including electricity generation based on several technologies, storage and demand response. Resource management gains an increasing relevance in this competitive context, while demand side active role provides managers with increased demand elasticity. This makes demand response use more interesting and flexible, giving rise to a wide range of new opportunities.This paper proposes a methodology for managing demand response programs in the scope of virtual power players. The proposed method is based on the calculation of locational marginal prices (LMP). The evaluation of the impact of using demand response specific programs on the LMP value supports the manager decision concerning demand response use. The proposed method has been computationally implemented and its application is illustrated in this paper using a 32 bus network with intensive use of distributed generation.

Reconceptualising public spaces of (IN)equality: sensing and creating layers of visibility

Tese apresentada para cumprimento dos requisitos necessários à obtenção do grau de Doutor em Geografia e Planeamento Territorial - Especialidade: Geografia Humana

Uncertain Spaces: Virtual Configurations in Contemporary Art and Museums

Contém artigos apresentados na International Conference “Uncertain Spaces: Virtual Configurations in Contemporary Art and Museums”, na Fundação Calouste Gulbenkian (Lisboa), 31 Outubro - 1 de Novembro de 2014) de: Helena Barranha e Susana S. Martins - Introduction: Art, Museums and Uncertainty (pp.1-12); Alexandra Bounia e Eleni Myrivili - Beyond the ‘Virtual’: Intangible Museographies and Collaborative Museum Experiences (pp.15-32); Annet Dekker - Curating in Progress. Moving Between Objects and Processes (pp.33-54); Giselle Beiguelman - Corrupted Memories. The aesthetics of Digital Ruins and the Museum of the Unfinished (pp.55-82); Andrew Vaas Brooks - The Planetary Datalinks (pp.85-110); Sören Meschede - Curators’ Network: Creating a Promotional Database for Contemporary Visual Arts (pp.11-130); Stefanie Kogler - Divergent Histories and Digital Archives of Latin American and Latino Art in the United States – Old Problems in New Digital Formats (pp.131-156); Luise Reitstätter e Florian Bettel - Right to the City! Right to the Museum!(pp.159-182); Roberto Terracciano - On Geo-poetic systems: virtual interventions inside and outside the museum space (pp.183-210); e, Catarina Carneiro de Sousa e Luís Eustáquio - Art Practice in Collaborative Virtual Environments (pp.211-240).

Managing marginal capital requirements in solvency II: Analysis of a real insurance portfolio

This thesis provides a complete analysis of the Standard Capital Requirements given by Solvency II for a real insurance portfolio. We analyze the investment portfolio of BPI Vida e Pensões, an insurance company affiliated with a Portuguese bank BPI, both at security, sub-portfolio and asset class levels. By using the Standard Formula from EIOPA, Total SCR amounts to 239M€. This value is mostly explained by Market and Default Risk whereas the former is driven by Spread and Concentration Risks. Following the methodology of Leblanc (2011), we examine the Marginal Contribution of an asset to the SCR which allows for the evaluation of the risks of each security given its characteristics and interactions in the portfolio. The top contributors to the SCR are Corporate Bonds and Term Deposits. By exploring further the composition of the portfolio, our results show that slight changes in allocation of Term and Cash Deposits have severe impacts on the total Concentration and Default Risks, respectively. Also, diversification effects are very relevant by representing savings of 122M€. Finally, Solvency II represents an opportunity for the portfolio optimization. By constructing efficient frontiers, we find that as the target expected return increases, a shift from Term Deposits/ Commercial Papers to Eurozone/Peripheral and finally Equities occurs.