Secure Querying of Recursive XML Views: A Standard XPath-based Technique

Most state-of-the art approaches for securing XML documents allow users to access data only through authorized views defined by annotating an XML grammar (e.g. DTD) with a collection of XPath expressions. To prevent improper disclosure of confidential information, user queries posed on these views need to be rewritten into equivalent queries on the underlying documents. This rewriting enables us to avoid the overhead of view materialization and maintenance. A major concern here is that query rewriting for recursive XML views is still an open problem. To overcome this problem, some works have been proposed to translate XPath queries into non-standard ones, called Regular XPath queries. However, query rewriting under Regular XPath can be of exponential size as it relies on automaton model. Most importantly, Regular XPath remains a theoretical achievement. Indeed, it is not commonly used in practice as translation and evaluation tools are not available. In this paper, we show that query rewriting is always possible for recursive XML views using only the expressive power of the standard XPath. We investigate the extension of the downward class of XPath, composed only by child and descendant axes, with some axes and operators and we propose a general approach to rewrite queries under recursive XML views. Unlike Regular XPath-based works, we provide a rewriting algorithm which processes the query only over the annotated DTD grammar and which can run in linear time in the size of the query. An experimental evaluation demonstrates that our algorithm is efficient and scales well.Comment: (2011

Driven to distraction: Determining the effects of roadside advertising on driver attention

There is growing concern that roadside advertising presents a real risk to driving safety, with conservative estimates putting external distractors responsible for up to 10% of all accidents. In this report, we present a simulator study quantifying the effects of billboards on driver attention, mental workload and performance in Urban, Motorway and Rural environments. The results demonstrate that roadside advertising has a clear detrimental effect on lateral control, increases mental workload and eye fixations, and on some roads can draw attention away from more relevant road signage. Detailed analysis of the data suggests that the effects of billboards may in fact be more consequential in scenarios which are monotonous or of lower workload. Nevertheless, the overriding conclusion is that prudence should be exercised when authorising or placing roadside advertising. The findings are discussed with respect to governmental policy and guidelines.Final report of a study funded by The Rees Jeffreys Road Fun

A child-centred exploration of the relevance of family and friends to theory of mind development

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2011 The Authors.Theory of Mind (ToM) is said to develop at around 4 years old. But some studies suggest it develops considerably earlier than this, with others suggesting it develops much later. Although several recent studies have found that social factors (like gender, family size, number of siblings, and number of friends) can impact on ToM, other studies contradict those findings. We wondered whether addressing several procedural issues and ensuring the task concerns real protagonists in real time, would bear on the above issues. Here, 114 children of 3–6 years completed four ToM tasks incorporating controls from experimental psychology, including randomly varying the order of ToM and non-ToM questions across participants. Now, children passed ToM tasks from around 5 years old, rather than 4 years or earlier. Girls did not develop ToM any earlier than boys. There was clear correlational evidence for the older-sibling effect and effects of friends but no reliable effects of nuclear or extended family. However, when these factors were set in the context of one another, the sibling effect was driven by a negative influence from younger siblings (as opposed to older siblings) and the friends effect was driven by friends at school (as opposed to friends at home). Finally, “friends” was a stronger predictor than siblings but memory (a cognitive factor) and age (a maturational factor) were the strongest predictors of all

A General Approach for Securely Querying and Updating XML Data

Over the past years several works have proposed access control models for XML data where only read-access rights over non-recursive DTDs are considered. A few amount of works have studied the access rights for updates. In this paper, we present a general model for specifying access control on XML data in the presence of update operations of W3C XQuery Update Facility. Our approach for enforcing such updates specifications is based on the notion of query rewriting where each update operation defined over arbitrary DTD (recursive or not) is rewritten to a safe one in order to be evaluated only over XML data which can be updated by the user. We investigate in the second part of this report the secure of XML updating in the presence of read-access rights specified by a security views. For an XML document, a security view represents for each class of users all and only the parts of the document these users are able to see. We show that an update operation defined over a security view can cause disclosure of sensitive data hidden by this view if it is not thoroughly rewritten with respect to both read and update access rights. Finally, we propose a security view based approach for securely updating XML in order to preserve the confidentiality and integrity of XML data.Comment: No. RR-7870 (2012

Bistabilité moléculaire dans des complexes de métaux de transition : commutation par un champ électrique et détection optique par résonance des plasmons de surface

De nos jours, les demandes technologiques en terme de miniaturisation de composants telles que les capteurs, les dispositifs pour l'électronique et l'optique stimulent de plus en plus l'activité scientifique des laboratoires à l'échelle mondiale. A cet effet, les matériaux moléculaires bistables semblent prometteurs dans la perspective de telles applications. L'adressage et la détection de la bistabilité dans ces matériaux à l'échelle nanométrique est une étape incontournable dans la conception de tels dispositifs. Dans ce contexte, ce travail de thèse présente une approche originale, non seulement pour l'adressage des matériaux moléculaires bistables par voie électrique, mais aussi pour la lecture de l'information stockée dans les matériaux moléculaires bistables à l'échelle nanométrique par voie électrique ou optique. A cet effet, nous avons étudié les propriétés de transport des complexes de coordination (RbxMn[Fe(CN)6]y·zH2O, NaxCo[Fe(CN)6]y·zH2O, Co3[W(CN)8]2(pyrimidine)4·6H2O et {Fe(HB(pz)3)2}) et nous avons pu mettre en évidence une commutation entre leurs deux états bistables par l'application d'un champs électrique. Nous avons également étudié théoriquement et expérimentalement la possibilité de détecter cette commutation dans des couches minces à l'aide de la résonance des plasmons de surface. Nous montrons que cette technique peut détecter des variations d'indice optique associées à la bistabilité même pour des couches ultra-minces (<10 nm). Ces résultats ouvrent de sérieuses perspectives pour l'intégration des complexes à transition de spin ou à transfert de charge dans des nano-circuits électriques et dans des dispositifs photoniques dont l'objectif est leurs possibles applications comme mémoire, capteurs ou dispositifs optiques adressables.The aim of the present cook coas to investigate the electrical and optical properties of scoichable malecular complexes, suchas spin crossover of valence tautomeric comprends. We performed a detailed Raman spectroscopic stuby on three different Valence tautomeric compound under au opplied enternal electric field. We have beenable to provide experimental evidence for a new type of electric field induced transition in thes compounds. In the second part of this cook, we developed a novel approch for the setection of spin crossover in nanometric thim films co free sensing is based on surface plasmon resonance (SPR) detection of refractive index changes in the films

Aspects du développement psychologique de l’enfant au Maghreb

Les études sur le développement psychologique tant psychomoteur qu'affectif de l'enfant maghrébin sont encore rares, de même que les écrits et travaux concernant sa famille et son environnement. Ce texte condensé, limité en raison des impératifs rédactionnels, synthétise un certain nombre de données d'ordres variés en pointant ce qui nous semble généralement mal connu concernant le Maghreb. C'est notamment le cas des informations concernant l'Islam. De même en privilégiant la question de la fillette, nous avons voulu pointer l'un des problèmes socioculturels et politique majeurs du monde moderne en terre d'Islam: celui de la citoyenne de demain, dans un monde en changement; cette problématique apparaissant essentielle pour tout travail dans le champ de la santé mentale. Repères historico-culturels.Studies on the psychological development of the Maghreb child, from the psychomotor as well as the emotional points of view, are still quite rare, as is literature and research on the Maghreb child's family and environment. This article synthesizes various data, while identifying what is generally unknown or misunderstood about the Maghreb. This is namely the case of information surrounding the Islam faith. Also, by raising questions about the female child, the author examines one of today's major sociocultural and political problems in Islamic countries: the female citizen of tomorrow in a changing world - an issue which the author considers essential to any endeavour in the field of mental health

Visions of Unification and Integration: Building Brains and Communities in the European Human Brain Project

The Human Brain Project (HBP) was launched in October 2013 by the European Commission to build an information and communication technology infrastructure that would support large-scale brain modelling and simulation. Less than a year after its launch, more than 800 neuroscientists signed a letter that claimed the HBP ‘would fail to meet its goals’. Based on multi-sited ethnographic fieldwork conducted between February 2014 and January 2017 in France, Germany, the United Kingdom and the HBP headquarters in Switzerland, and over 40 interviews with scientists, engineers and project administrators, this article traces how competing visions over how brain models should be built became tied into debates over how scientific communities should be governed. Articulations of these different kinds of models and communities appealed to competing imaginaries of Europe itself – of Europe and European science as unified or pluralistic. This article argues that scientific models are sites of contestation over social and political futures. The tensions between visions of scientific unification and pluralism in the HBP mirrored the tensions between imaginaries of European political unification and pluralism