Unification and Logarithmic Space

We present an algebraic characterization of the complexity classes Logspace and NLogspace, using an algebra with a composition law based on unification. This new bridge between unification and complexity classes is inspired from proof theory and more specifically linear logic and Geometry of Interaction. We show how unification can be used to build a model of computation by means of specific subalgebras associated to finite permutations groups. We then prove that whether an observation (the algebraic counterpart of a program) accepts a word can be decided within logarithmic space. We also show that the construction can naturally represent pointer machines, an intuitive way of understanding logarithmic space computing

Les contrats TFM de génie civil

Les diverses missions dévolues au groupe TFM de la division ST comprennent les travaux, la maintenance et les dépannages en matière de génie civil notamment. Les travaux induits par ces missions sont confiés, par l'entremise de contrats à résultats, à diverses entreprises spécialisées. Cet exposé se propose de parcourir les différentes étapes qui président à la conclusion des contrats et, plus particulièrement les critères économiques et techniques. Recherche et garantie du meilleur rapport service, qualité / coût. Pourquoi les contrats, quels en sont les avantages et les inconvénients ? Utilisation universelle aisée par l'apport du soutient technique et économique, avec l'assurance du respect des prix, de la qualité, des délais et des garanties. Contrôles techniques et économiques, évolution

La carbonatation du béton armé

Ce document présente les divers aspects de la carbonatation du béton armé: Description des diverses réactions chimiques qui conduisent à la carbonatation des bétons. Comment le pH du béton se modifie laissant les armatures dans un milieu acide, donc corrosif. Description des conséquences sur les bétons et les armatures. Formation de cloques de surface, éclatement et perte de résistance. Méthodes d'investigation des dégâts d'ouvrages en béton armé visuelle, électrique, et par carottage. Prophylaxie passive et active: disposition des armatures lors de la réalisation, utilisation d'armatures ydables ou de fers enrobés de peinture epoxydique, protection des aciers lors de travaux d'assainissement. Principes d'assainissement du béton armé sur ouvrages anciens. Purge des bétons, passivation et protection des armatures et reconstitution au mortier de résine, ou passivation par infiltration du béton. Impact sur les ouvrages du CERN et conséquences financières prévisibles

Logic Programming and Logarithmic Space

We present an algebraic view on logic programming, related to proof theory and more specifically linear logic and geometry of interaction. Within this construction, a characterization of logspace (deterministic and non-deterministic) computation is given via a synctactic restriction, using an encoding of words that derives from proof theory. We show that the acceptance of a word by an observation (the counterpart of a program in the encoding) can be decided within logarithmic space, by reducing this problem to the acyclicity of a graph. We show moreover that observations are as expressive as two-ways multi-heads finite automata, a kind of pointer machines that is a standard model of logarithmic space computation

Polarization state of the optical near-field

The polarization state of the optical electromagnetic field lying several nanometers above complex dielectric structures reveals the intricate light-matter interaction that occurs in this near-field zone. This information can only be extracted from an analysis of the polarization state of the detected light in the near-field. These polarization states can be calculated by different numerical methods well-suited to near--field optics. In this paper, we apply two different techniques (Localized Green Function Method and Differential Theory of Gratings) to separate each polarisation component associated with both electric and magnetic optical near-fields produced by nanometer sized objects. The analysis is carried out in two stages: in the first stage, we use a simple dipolar model to achieve insight into the physical origin of the near-field polarization state. In the second stage, we calculate accurate numerical field maps, simulating experimental near-field light detection, to supplement the data produced by analytical models. We conclude this study by demonstrating the role played by the near-field polarization in the formation of the local density of states.Comment: 9 pages, 11 figures, accepted for publication in Phys. Rev.

Subjective experience of episodic memory and metacognition: a neurodevelopmental approach.

Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts, and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive paradigms such as the feeling of knowing). We start by considering healthy development, and provide a brief review of the development of episodic memory, with a particular focus on the ability of children to report first-person experiences of remembering. We then consider neurodevelopmental disorders (NDDs) such as amnesia acquired in infancy, autism, Williams syndrome, Down syndrome, or 22q11.2 deletion syndrome. This review shows that different episodic processes develop at different rates, and that across a broad set of different NDDs there are various types of episodic memory impairment, each with possibly a different character. This literature is in agreement with the idea that episodic memory is a multifaceted process

Spirituality, Religiosity, and Gerotranscendence

Gerotranscendence is a new theory of human development that extends to old age. This developmental process is characterized by a shift in metaperspective from a realistic view of the world to a more transcendent or cosmic perspective. The purpose of this study is to explore the relationship between age, gender, spirituality, and religiosity on gerotranscendence. Qualitative surveys were distributed to 174 residents of an independent living unit in the Midwest. The survey was used to measure respondents’ age, gender, spirituality, religiosity, and gerotranscendence. The finding did not support the hypothesis that age correlated with level of gerotranscendence. Demographic characteristics of the sample could have skewed the statistics. The relationship between gender and gerotranscendence could not be analyzed due to the lack of responses from males. Both spirituality and religiosity had a significant, positive correlate to gerotranscendence, with spirituality showing a slightly stronger correlation. These results indicate that although both variables are important contributing factors to one’s sense of gerotranscendence, spirituality seems to be the broader concept that incorporates characteristics of religiosity. Implications for developing spirituality and religiosity in the elderly such as staff education, spiritual/religious diversity training, and including spirituality and religiosity as part of a holistic treatment plan, are discussed