Linear logic for non-linear storytelling

Abstract. Whilst narrative representations have played a prominent role in AI research, there has been a renewed interest in the topic with the development of interactive narratives. A typical approach aims at generating narratives from baseline action representations, most often using planning techniques. However, this research has developed empirically, often as an application of planning. In this paper, we explore a more rigorous formalisation of narrative concepts, both at the action level and at the plot level. Our aim is to investigate how to bridge the gap between action descriptions and narrative concepts, by considering the latter from the perspective of resource consumption and causality. We propose to use Linear Logic, often introduced as a logic of resources, for it provides, through linear implication, a better description of causality than in Classical and Intuitionistic Logic. Besides advances in the fundamental principles of narrative formalisation, this approach can support the formal validation of scenario description as a preliminary step to their implementation via other computational formalisms.

Problématique de l'homogénnéisation des matériaux artificiels et résonnants présentant un indice de réfraction négatif

Cette étude traite de métamatériaux à indice de réfraction négatif constitués d'une répartition périodique de tiges et anneaux résonants (aussi appelés Split Ring Resonators ou SRRs). Ces structures ayant des dimensions électriques voisines d'un dixième de la longueur d'onde, l'approximation des milieux effectifs est généralement faite et la permittivité et la perméabilité effectives sont calculées au sens de Fresnel. En effet, malgré la nature composite du milieu, nous l'assimilerons à un matériau homogène auquel nous affecterons des grandeurs macroscopiques identiques matériaux classique. Cependant, des auteurs ont démontré l'existence d'une bande de fréquence où la partie imaginaire de la permittivité est positive. Cette observation contredit notre intuition physique car cette partie imaginaire, représentant des pertes, devrait être négative quel que soit le signe de la partie réelle. La procédure d'homogénéisation de tels milieu semble donc avoir des limites. L'objectif de notre étude est d'interpréter les paramètres effectifs dans cette bande de fréquence anormale. Nous démontrons que leur validité au sens des équations de Fresnel est contestable. La participation d'onde évanescente à la propagation au sein de la structure périodique rend sa description macroscopique difficile. Dans la bande de fréquence où ces paramètres sont définis correctement, l'indice effectif atteint une valeur maximale dictée par la structuration du métamatériau

Generalized analysis of the deposition/splashing limit for one- and two-component droplet impacts upon thin films

[EN] Single drop impacts on thin liquid layers are of particular interest because of the ejection of secondary droplets, the so-called splashing. Only a few studies handle the deposition/splashing limit for two-component interaction, where the liquid properties of the impacting drop and wall film differ significantly. This study aims at identifying a unified approach for one- and two-component interactions to determine the deposition/splashing limit. Therefore, a large database of both interactions is considered, which includes data from literature for one-component interactions plus the following binary combinations: hyspin-hexadecane, diesel-hexadecane and diesel-motor oil. Furthermore, a systematic study of two-component interactions with several silicon oils and hexadecane is performed. To map the outcomes, the Ohnesorge number Oh and the Reynolds number Re calculated with arithmetically averaged fluid properties between droplet and wall film fluid are chosen. The dimensionsless film thickness δ is added to form a 3D plot, where one- and two-component experiments are combined. Existing correlations from the literature are revised regarding both interactions and their consistency is checked. The investigated range of high viscosity fluids allow us to propose an improvement of the correlation for high Oh. Our results show that the arithmetically averaged fluid properties lead to a good repartition of both one- and twocomponents interactions toward the deposition/splashing limit. They also corroborate the previous findings that an increase of δ inhibits splashing but its influence is decreasing with increasing Oh.The authors kindly acknowledge the financial support of this work by the Deutsche Forschungsgemeinschaft (DFG) in the frame of the International Research Training Group "Droplet Interaction Technologies" (DROPIT)Bernard, R.; Foltyn, P.; Geppert, A.; Lamanna, G.; Weigand, B. (2017). Generalized analysis of the deposition/splashing limit for one- and two-component droplet impacts upon thin films. En Ilass Europe. 28th european conference on Liquid Atomization and Spray Systems. Editorial Universitat Politècnica de València. 730-737. https://doi.org/10.4995/ILASS2017.2017.4810OCS73073

La detention d'actifs risques selon l'age: Une etude econometrique / Aging and the Demand for Risky Assets: An Econometric Study.

Cet article se propose d’étudier l’influence de l’âge sur la composition des patrimoines, notamment sur la détention d’actifs risqués. En effet, une hypothèse souvent avancée est que, plus l’horizon de vie se raccourcit, plus la détention d’actifs risqués devrait se réduire. Cette hypothèse repose néanmoins sur une interprétation fallacieuse de la loi des grands nombres (pour reprendre l’expression de Samuelson). En outre, on peut avancer que les seniors, n’étant plus exposés aux risques du marché du travail (perte d’emploi, réduction de salaire, aléas de carrière), peuvent prendre plus de risques financiers. Après avoir présenté les arguments théoriques en faveur d’un accroissement de la détention d’actifs risqués avec l’âge, nous testons leur pertinence à partir des données de l’Enquête Patrimoine 1998 de l’Insee. A l’aide de techniques économétriques, nous montrons notamment que les individus les plus âgés sont plus fréquemment détenteurs d’actifs risqués, et que la part d’actifs risqués qu’ils détiennent est significativement plus importante que pour les autres classes d’âge. Inversement, les individus plus jeunes, éventuellement soumis à plus de risques par ailleurs (notamment sur le marché du travail) sont moins incités à prendre des risques financiers.The age structure of the French population has been experiencing dramatic changes over the past decades and is likely to do so in a near future. The increasing proportion of elder people may modify the savings behavior of French households. The level of savings, as well as its composition, may be altered by the aging of the French population. This paper analyses the influence of age on the composition of wealth. In fact, there is a widespread opinion that the shorter the lifetime horizon, the thinner the share of risky assets in the total wealth should be. Yet this assertion relies on a misinterpretation of the Law of Large Numbers. Moreover, it may be argued that elder individuals, as far as they no longer face risks on the labour market, may take risks on the financial market. After a short review of the theoretical arguments in favour of an increasing holding of risky assets with age, we test the relevance of these arguments on French survey data (1998) using Probit and Logit regressions. We show that elder households are more likely to hold risky assets than younger ones, and that the share of risky assets is increasing with age. On the contrary the youngest households, presumably because they face more background risks, have a smaller part of their wealth in risky assets.savings; risky assets; portfolio selection; épargne; vieillissement; actifs risqués; choix de portefeuille; Aging;

Abnormal response to negative feedback in depression

Background. Recent studies have suggested that subjects with depression suffer a diagnosis-specific motivational deficit, characterized by an abnormal response to negative feedback that endures beyond clinical recovery. Furthermore, it has been suggested that negative feedback may motivate non-depressed controls, but not depressed patients, to improve their performance in neuropsychological tests. Methods. We describe two studies. The first compared performance on the simultaneous and delayed match to sample (SDMS) task from the CANTAB neuropsychological test battery, in 20 patients with severe depression with 20 with acute schizophrenia, 40 with chronic schizophrenia and 40 healthy controls. The second examined the performance of depressed patients with diurnal variation in symptoms and cognitive function. Results. All patients groups showed impairments on the simultaneous and delayed match to sample task compared to controls. Depressed patients did not show an abnormal response to negative feedback. Controls did not show a motivational effect of negative feedback. Depressed patients with diurnal variation showed no variation in their response to perceived failure. There was no evidence of abnormal response to negative feedback in any patient group using the ‘runs test’ or of a motivational effect in controls. Conditional probability analysis was not independent of the total number of errors made in the SDMS task. Conclusions. Further studies are suggested to examine whether an abnormal response to negative feedback characterizes particular subgroups of patients suffering from depression

Cycles in the chamber homology of GL(3)

Let F be a nonarchimedean local field and let GL(N) = GL(N,F). We prove the existence of parahoric types for GL(N). We construct representative cycles in all the homology classes of the chamber homology of GL(3).Comment: 45 pages. v3: minor correction

Cancer symptom awareness and barriers to medical help seeking in Scottish adolescents:a cross-sectional study

Background: Initiatives to promote early diagnosis include raising public awareness of signs and symptoms ofcancer and addressing barriers to seeking medical help about cancer. Awareness of signs and symptoms of cancerand emotional barriers, such as, fear, worry, and embarrassment strongly influence help seeking behaviour. Whetheranxiety influences seeking medical help about cancer is not known. The purpose of this study about adolescentswas to examine: 1) the relationship between contextual factors and awareness of signs and symptoms of cancerand barriers (including emotional barriers) to seeking medical help, and 2) associations between anxiety andendorsed barriers to seeking medical help. Interpretation of data is informed by the common sense model of theself-regulation of health and illness.Methods: A cross-sectional study of 2,173 Scottish adolescents (age 12/13 years) using the Cancer AwarenessMeasure. Socio-demographic questions were also included. Descriptive statistics were calculated and two Poissonregression models were built to determine independent predictors of: 1) the number of cancer warning signsrecognized, and; 2) number of barriers to help seeking endorsed.Results: Analysis identified that knowing someone with cancer was a significant independent predictor ofrecognising more cancer warning signs whereas Black and Minority Ethnic status was a significant independentpredictor of recognising fewer cancer warning signs. Emotional barriers were the most commonly endorsed,followed by family, service and practical barriers. Over two thirds of adolescents were ‘worried about what thedoctor would find’ and over half were ‘scared’. Higher anxiety scores, knowing more cancer warning signs andfemale gender were significant independent predictors of barriers to help seeking.Conclusion: Improving cancer awareness and help seeking behaviour during adolescence may contribute to earlypresentation. Contextual factors (for example, ethnicity, gender, knowing someone with cancer), and emotionaldimensions (for example, anxiety, fear, worry) are critical components in help seeking behaviours. The role ofemotional factors indicates that public health campaigns focused on awareness and help seeking may benefit fromhaving a more emotional focus, for example, including references to feelings, such as, fears and worries

Diagnosis of Pneumonia in Children with Dehydrating Diarrhoea

The World Health Organization (WHO) guidelines for diagnosis of pneumonia are based on the history of cough or difficult breathing and age-adjusted respiration rates. Metabolic acidosis associated with dehydrating diarrhoea also influences the respiration rate. Two hundred and four children, aged 2 to 59 months, with dehydrating diarrhoea and a history of cough and/or fast breathing, were enrolled in a prospective study. Pneumonia diagnoses were made on enrollment and again 6 hours post-enrollment (after initial rehydration), using the WHO guidelines. These were compared with investigators\u2019 clinical diagnosis based on history and findings of physical examination and a chest x-ray at the same time points. Using the WHO guidelines, 149/152 (98%) infants in the 2-11 months age-group and 38/40 (95%) children in the 12-59 months age-group were diagnosed to have pneumonia on enrollment, which dropped to 107 (70%) and 30 (75%) respectively at 6 hours post-enrollment. The specificity of the WHO guidelines for diagnosis of pneumonia was very low (6.9%) at enrollment but increased to 65.5% at 6 hours post-enrollment, after initial rehydration. The specificity of the WHO guidelines for diagnosis of pneumonia in young children is significantly reduced in dehydrating diarrhoea. For young children with dehydrating diarrhoea, rehydration, clinical and radiological assessments are useful in identifying those with true pneumonia