Temporal Data Modeling and Reasoning for Information Systems

Temporal knowledge representation and reasoning is a major research field in Artificial Intelligence, in Database Systems, and in Web and Semantic Web research. The ability to model and process time and calendar data is essential for many applications like appointment scheduling, planning, Web services, temporal and active database systems, adaptive Web applications, and mobile computing applications. This article aims at three complementary goals. First, to provide with a general background in temporal data modeling and reasoning approaches. Second, to serve as an orientation guide for further specific reading. Third, to point to new application fields and research perspectives on temporal knowledge representation and reasoning in the Web and Semantic Web

A Type Language for Calendars

Time and calendars play an important role in databases, on the Semantic Web, as well as in mobile computing. Temporal data and calendars require (specific) modeling and processing tools. CaTTS is a type language for calendar definitions using which one can model and process temporal and calendric data. CaTTS is based on a "theory reasoning" approach for efficiency reasons. This article addresses type checking temporal and calendric data and constraints. A thesis underlying CaTTS is that types and type checking are as useful and desirable with calendric data types as with other data types. Types enable (meaningful) annotation of data. Type checking enhances efficiency and consistency of programming and modeling languages like database and Web query languages

A Reasoner for Calendric and Temporal Data

Calendric and temporal data are omnipresent in countless Web and Semantic Web applications and Web services. Calendric and temporal data are probably more than any other data a subject to interpretation, in almost any case depending on some cultural, legal, professional, and/or locational context. On the current Web, calendric and temporal data can hardly be interpreted by computers. This article contributes to the Semantic Web, an endeavor aiming at enhancing the current Web with well-defined meaning and to enable computers to meaningfully process data. The contribution is a reasoner for calendric and temporal data. This reasoner is part of CaTTS, a type language for calendar definitions. The reasoner is based on a \theory reasoning" approach using constraint solving techniques. This reasoner complements general purpose \axiomatic reasoning" approaches for the Semantic Web as widely used with ontology languages like OWL or RDF

Changing Patterns of Income Inequality in U.S. Counties, 1970–2000

The upswing in economic inequality that has affected a number of advanced industrial societies in the late 20th century has been particularly conspicuous in the United States. The authors explore its causes using data on the distribution of family income in 3,098 U.S. counties in 1970, 1980, 1990, and 2000. The authors build a model of within-county income inequality that assumes that distribution processes involving labor market and sociodemographic variables operate primarily at the county level and those involving the political and institutional context operate primarily at the state level. Multilevel methods are used to distinguish county cross-sectional, state cross-sectional, and longitudinal effects on inequality. The authors find that, when features of the state-level institutional and political context are associated with inequality, these effects are larger longitudinally than cross-sectionally. A range of other factors, including economic development, labor force changes, shifts in the racial/ethnic and gender composition of the labor force, educational expansion, and urbanization are found to have comparatively large effects, both longitudinally and cross-sectionally

Emotional Pre-eminence of Human Vocalizations

Human vocalizations (HV), as well as environmental sounds, convey a wide range of information, including emotional expressions. The latter have been relatively rarely investigated, and, in particular, it is unclear if duration-controlled non-linguistic HV sequences can reliably convey both positive and negative emotional information. The aims of the present psychophysical study were: (i) to generate a battery of duration-controlled and acoustically controlled extreme valence stimuli, and (ii) to compare the emotional impact of HV with that of other environmental sounds. A set of 144HV and other environmental sounds was selected to cover emotionally positive, negative, and neutral values. Sequences of 2s duration were rated on Likert scales by 16 listeners along three emotional dimensions (arousal, intensity, and valence) and two non-emotional dimensions (confidence in identifying the sound source and perceived loudness). The 2s stimuli were reliably perceived as emotionally positive, negative or neutral. We observed a linear relationship between intensity and arousal ratings and a "boomerang-shaped” intensity-valence distribution, as previously reported for longer, duration-variable stimuli. In addition, the emotional intensity ratings for HV were higher than for other environmental sounds, suggesting that HV constitute a characteristic class of emotional auditory stimuli. In addition, emotionally positive HV were more readily identified than other sounds, and emotionally negative stimuli, irrespective of their source, were perceived as louder than their positive and neutral counterparts. In conclusion, HV are a distinct emotional category of environmental sounds and they retain this emotional pre-eminence even when presented for brief period

The reputation of the euro and the European Central Bank: interlinked or disconnected?

The Eurozone crisis had a clear impact on trust in the euro and the European Central Bank (ECB). However, drawing on a new study, Stephanie Bergbauer, Nils Hernborg, Jean-François Jamet and Eric Persson explain that there are significant differences in the way citizens place trust in the euro and the ECB. They find that while support for the euro is primarily value based, trust in the ECB depends predominantly on citizens’ satisfaction with the EU’s overall performance and citizens’ outlooks on the economy

Thermodynamic and Transport properties of fluids: towards a single LJ-SAFT like molecular model valid for n-alkanes ?

International audienceApart from the low density conditions, there is still a lack of a molecular based approach able to provide both equilibrium and transport properties using the same molecular parameters in all fluid regimes (gas, liquid and supercritical). This is even more critical when dealing with poly-atomic fluids. This lack is largely due to the fact that a comprehensive theory is still not available for evaluating the transport properties in dense fluids in terms of a realistic molecular model, i.e. molecular structure and interaction potentials. However, from the equilibrium properties side, the combination of the Lennard-Jones Chain (LJC) molecular model with the Statistical Associating Fluid Theory (SAFT) is able to represent very well the thermodynamic properties of a great variety of fluids [1]. Furthermore, combined with Density Functional or Density Gradient Theory, these approaches are capable to yield very good results on interfacial properties for the same systems [2]. Additionally, based on Molecular Dynamics simulations results, has been proposed recently semi-empirical accurate correlation to describe viscosity [3] and thermal conductivity [4] of the LJC fluid model over a wide range of thermodynamic states. So, in this work, we have used the LJC molecular model combined with LJ-SAFT and transport properties correlation on normal alkanes (methane, n-butane, n-heptane and n-decane) along the vapour/liquid coexistence line. The idea was to test if, with a single set of molecular parameters for each n-alkane, this model was able to provide a reasonable estimate of both thermodynamic and transport properties. Good results have been obtained for methane (monomer) and n-butane (dimer) except for thermal conductivity in the gas state. For n-heptane (trimer) and n-decane (quadrimer) it has been found that both viscosity and thermal conductivity are not always well estimated using this approach. It will be shown that these trends are fully related to the bad modelling of the internal degrees of freedom when using the LJC model. Furthermore using molecular dynamics simulation it will be shown that, for viscosity, a single additional "rigidity" parameter allows to strongly improve all the results. [1] S. P. Tan, H. Adidharma, M. Radosz, Ind. Eng. Chem. Res., 47 (2008), 8063-8082. [2] P. Paricaud, A. Galindo, G. Jackson, Fluid Phase Equilib 194-197 (2002), 87-96. [3] G. Galliero, C. Boned, Phys. Rev. E, 79 (2009) 021201. [4] G. Galliero, C. Boned, Phys. Rev. E, 80 (2009) 061202

Association between social relationships and survival of Swiss octogenarians. A five-year prospective, population-based study

Background and aims: Data from the literature reveal the contrasting influences of family members and friends on the survival of old adults. On one hand, numerous studies have reported a positive association between social relationships and survival. On the other, ties with children may be associated with an increased risk of disability, whereas ties with friends or other relatives tend to improve survival. A five-year prospective, population-based study of 295 Swiss octogenarians tested the hypothesis that having a spouse, siblings or close friends, and regular contacts with relatives or friends are associated with longer survival, even at a very old age. Methods: Data were collected through individual interviews, and a Cox regression model was applied to assess the effects of kinship and friendship networks on survival, after adjusting for socio-demographic and health-related variables. Results: Our analyses indicate that the presence of a spouse in the household is not significantly related to survival, whereas the presence of siblings at baseline improves the oldest old's chances of surviving five years later. Moreover, the existence of close friends is a central component in the patterns of social relationships of oldest adults, and one which is significantly associated with survival. Overall, the protective effect of social relationships on survival is more related to the quality of those relationships (close friends) than to the frequency of relationships (regular contacts). Conclusions: We hypothesize that the existence of siblings or close friends may beneficially affect survival, due to the potential influence on the attitudes of octogenarians regarding health practices and adaptive strategie