Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
See detailHamlet : réflexions sur la modernité d’un mythe
Delville, Michel ULg; Michel, Pierre

Scientific conference (2004, October 23)

Detailed reference viewed: 8 (1 ULg)
Full Text
See detailHamlet = Don Juan. L'unique pièce de Buñuel et son contexte culturel
Ceballos Viro, Alvaro ULg

Article for general public (2010)

Detailed reference viewed: 40 (12 ULg)
See detailHamlet et les Renaissances en Europe
Delville, Michel ULg; Michel, Pierre ULg

Scientific conference (2008, February 12)

Detailed reference viewed: 7 (0 ULg)
Full Text
Peer Reviewed
See detailHammer head beam solution for beam-to-column joints in seismic resistant building frames
Hoang, Van Long ULg; Jaspart, Jean-Pierre ULg; Demonceau, Jean-François ULg

in Journal of Constructional Steel Research (2014)

This paper presents a research on an innovative stiffened extended end-plate joint, used to connect I-shaped beams to partially-encased composite wide flange columns. In the joint, T-shaped hammer heads ... [more ▼]

This paper presents a research on an innovative stiffened extended end-plate joint, used to connect I-shaped beams to partially-encased composite wide flange columns. In the joint, T-shaped hammer heads cut from the same I-profiles than the beams are used, instead of using traditional haunches. At the joint level, the column web is strengthened by two lateral plates welded to the column flanges; these plates also reinforce the column flanges. This type of joint is proposed to use in the seismic resistance building frames, as a full-strength and a fully-rigid joint solution. Firstly, a test program carried out within a RFCS European project titled HSS-SERF “High Strength Steel in Seismic Resistant Building Frames”, 2009–2013, will be presented. Then, analytical developments based on the component approach and aimed at predicting the joint response will be described; their validity will be demonstrated through comparisons with the tests. Moreover, a new design concept for full strength joint accounting for the actual position of the plastic hinge and the possible individual overstrength factors for each component is proposed, respecting the requirements of EN1998-1-1. [less ▲]

Detailed reference viewed: 4 (2 ULg)
Full Text
See detailHammett Acidity Scale in Ionic Liquids : An Indication of Their Weak Dissociating Character
Robert, Thierry ULg; Magna, Lionel; Olivier-Bourbigou, Hélène et al

Poster (2010, August)

Ionic liquids are salts with the particularity to exhibit melting points near room temperature (below 100°C, by convention) with no vapour tension. For this last reason, ionic liquids are sometimes called ... [more ▼]

Ionic liquids are salts with the particularity to exhibit melting points near room temperature (below 100°C, by convention) with no vapour tension. For this last reason, ionic liquids are sometimes called “green solvents”. In addition, their exclusive materials and solvent properties has led to an amazing increase of interest from both academic and industrial community, confirmed by the explosion of the number of published papers in the last decade. The many combinations of organic and inorganic cations and anions allow an infinity of new ionic solvents then permitting the selection of the desired properties for a given application. Nevertheless, it is impossible to investigate all these combinations and the unusual complexity of these new solvents gives rise to many controversies. Consequently, the development of the general rules for understanding the chemistry in ionic liquids is crucial. A fundamental property of solvent is its solvating power, for instance towards the proton. Therefore, we are interested to investigate the acid-base properties in ionic liquids in order to ultimately find a correlation with the acidic catalysis activity. We then have proposed a colorimetric method to determine the acidity levels accessible in these new media: the Hammett acidity function H0. This spectroscopic method is based on the protonation equilibrium for a family of coloured indicator with pKa’s assumed as solvent independent (following the Hammett proposition). This presentation will summarize our Hammett acidity measurements in several ionic liquids. - At first, we will show that it is possible to evaluate the Hammett acidity function with two different coloured indicators, in the same ionic liquid. Since the Hammett acidity of a given mixture was found to depend on the choosen coloured indicator, this suggests the formation of ions associations in ionic liquids. As a result, the ionic liquids are clearly not as dissociating as initially thought and the Hammett acidity function is in fact an apparent function, underestimating the real acidity level. - The apparent acidity functions have then been compared for several ionic liquids to which an acid has been added ([BMIm][NTf2], [BMIm][BF4], [BMIm][OTf], [BHIm][NTf2], [BMIm][PF6], [HNEt3][NTf2]). The conclusions are as follows: 1) the accessible acidity level is not influenced by the nature of the cation; 2) on the contrary, the nature of anion is very critical and the solvating power towards the proton follows the order: OTf- > NTf2- > BF4- > PF6-. The more the proton is solvated, the less it is acidic. - Finally, the difference of acidity of two acids, HOTf and HNTf2 (both strong acids in water), has been investigated in [BMIm][BF4], [BMIm][NTf2] and [BMIm][OTf]. In [BMIm][OTf], these two acids show the same acidity (they behave as strong acids) due to the solvent levelling effect; on the other hand, in [BMIm][NTf2] and [BMIm][BF4] allowing higher acidity levels, HNTf2 is stronger than HOTf . The observed difference is also another indication of the lower proton solvation in [BMIm][BF4] or [BMIm][NTf2] versus that in [BMIm][OTf]. [less ▲]

Detailed reference viewed: 335 (12 ULg)
Full Text
Peer Reviewed
See detailLe hamster commun (Cricetus cricetus L.) en Belgique: statut actuel et ancien des populations
Libois, Roland ULg; Rosoux, René

in Belgian Journal of Zoology (1982), 112(2), 227-236

Fossif remains of hamsters from the late Pleistocene were found in Belgium. But this animal seems to have disappeared between that period and the mid 19th century. When again registrated it was only found ... [more ▼]

Fossif remains of hamsters from the late Pleistocene were found in Belgium. But this animal seems to have disappeared between that period and the mid 19th century. When again registrated it was only found in the "le pays de Herve" between Herve and Limbourg. Then it progressively reached the center of Brabant, the westernmost part of its range. In the early 20th century, hamsters were so numerous that people were going through an aradication campaign to prevent the damaging of their crops. However, we believe that the major reasons of its present scarcity were the sound modifications of the agricultural technology and landscape (mechanization, regrouping of land, deep ploughing after the harvest...) Hamsters live now in Hesbaye, the Pays de Herve and in the east of Brabant. But they are so few that it appears to take some conservation measures [less ▲]

Detailed reference viewed: 73 (2 ULg)
Full Text
Peer Reviewed
See detailHamstring muscle strain recurrence and strength performance disorders
Croisier, Jean-Louis ULg; Forthomme, Bénédicte ULg; Namurois, Marie-Hélène ULg et al

in American Journal of Sports Medicine (2002), 30(2, Mar-Apr), 199-203

We determined the frequency of strength disorders in 26 athletes with a history of hamstring muscle injury and recurrent strains and discomfort. We also assessed the effectiveness of rehabilitation to ... [more ▼]

We determined the frequency of strength disorders in 26 athletes with a history of hamstring muscle injury and recurrent strains and discomfort. We also assessed the effectiveness of rehabilitation to correct muscle performance. After concentric and eccentric isokinetic assessment, 18 athletes were found to have strength deficits, as determined by statistically selected cutoffs of peak torque, bilateral differences, and the flexors/quadriceps ratio. The discriminating character of the eccentric trial was demonstrated, combining a preferential eccentric peak torque deficit and a significant reduction of the mixed eccentric flexors/concentric quadriceps ratio. The athletes with muscle imbalances followed a rehabilitation program individually adapted from their strength profile. Treatment length was from 10 to 30 sessions and resulted in isokinetic parameter normalization in 17 of 18 subjects. Isokinetically corrected subjects were observed for 12 months after return to athletics. None sustained a clinically diagnosed hamstring muscle reinjury. Subjective intensity of pain and discomfort were significantly reduced, and they all returned to their prior level of competition. These results demonstrate that persistent muscle strength abnormalities may give rise to recurrent hamstring injuries and discomfort. An individualized rehabilitation program emphasizing eccentric training based on specific deficits contributes to a decrease in symptoms on return to sports. [less ▲]

Detailed reference viewed: 107 (15 ULg)
Peer Reviewed
See detailHamstring muscle strain: interest of the eccentric assessment and preventive aspects
Croisier, Jean-Louis ULg; Crielaard, Jean-Michel ULg

in Isokinetics & Exercise Science (2000, March), 8

Detailed reference viewed: 24 (0 ULg)
Full Text
See detailHanche douloureuse de l'enfant sportif
Kaux, Jean-François ULg

Learning material (2011)

Detailed reference viewed: 54 (8 ULg)
Full Text
See detailHand dermometrology
PIERARD, Gérald ULg; Pierard, Sébastien ULg; Franchimont, Claudine ULg et al

in Alikhan, A.; Lachapelle, J.M.; Maibach, M.I. (Eds.) Textbook of hand eczema. (2014)

Detailed reference viewed: 9 (0 ULg)
Full Text
Peer Reviewed
See detailA Hand Immersion Test under Laboratory-Controlled Usage Conditions: The Need for Sensitive and Controlled Assessment Methods
Paye, Marc ULg; Gomes, G.; Zerweck, C. R. et al

in Contact Dermatitis (1999), 40(3), 133-8

Exaggerated test conditions were frequently used to investigate the cutaneous tolerance of detergent products in the past. As the sensitivity of newly designed biometric methods is steadily improving, the ... [more ▼]

Exaggerated test conditions were frequently used to investigate the cutaneous tolerance of detergent products in the past. As the sensitivity of newly designed biometric methods is steadily improving, the trend towards more realistic test conditions should be encouraged. A hand immersion test under laboratory-controlled usage conditions is presently described, fulfilling such principles. Panelists soaked their hands in 2 different hand dishwashing liquids, 2x daily for 10 min each (with successive in-solution/out-of-solution cycles) for 4 consecutive days. Products were at usual dilution for dishwashing liquids and were randomized between the dominant and non-dominant hands of panelists. Visual scoring of erythema and dryness developing on the whole hands (scoring scales including interdigital areas and joints) during the week did not allow discrimination between the 2 products. However the dominant hands were significantly more susceptible to alterations than the non-dominant hands, regardless of product attribution. In contrast, skin electrical measurements (Corneometer CM800 and Skicon 200) on the dorsum of the hands (muscle mass between thumb and index) and squamometry analysis of tape stripping (harvested from the same site) yielded significant differences between the 2 products. In conclusion, a hand immersion test under realistic conditions has been described, which discriminates between products when sensitive assessment methods are used to explore skin sites partially protected from daily-life skin aggressions. [less ▲]

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailHand position on the bunch and source-sink ratio influence the banana fruit susceptibility to crown rot disease
Lassois, Ludivine ULg; Bastiaanse, H.; Chillet, M. et al

in Annals of Applied Biology (2010), 156

The postharvest development of crown rot of bananas depends notably on the fruit susceptibility to this disease at harvest. It has been shown that fruit susceptibility to crown rot is variable and it was ... [more ▼]

The postharvest development of crown rot of bananas depends notably on the fruit susceptibility to this disease at harvest. It has been shown that fruit susceptibility to crown rot is variable and it was suggested that this depends on environmental preharvest factors. However, little is known about the preharvest factors influencing this susceptibility. The aim of this work was to evaluate the extent to which fruit filling characteristics during growth and the fruit development stage influence the banana susceptibility to crown rot. This involved evaluating the influence of (a) the fruit position at different levels of the banana bunch (hands) and (b) changing the source–sink ratio (So–Si ratio), on the fruit susceptibility to crown rot. The fruit susceptibility was determined by measuring the internal necrotic surface (INS) after artificial inoculation of Colletotrichum musae. A linear correlation (r = −0.95) was found between the hand position on the bunch and the INS. The So–Si ratio was found to influence the pomological characteristics of the fruits and their susceptibility to crown rot. Fruits of bunches from which six hands were removed (two hands remaining on the bunch) proved to be significantly less susceptible to crown rot (INS = 138.3 mm2) than those from bunches with eight hands (INS = 237.9 mm2). The banana susceptibility to crown rot is thus likely to be influenced by the fruit development stage and filling characteristics. The present results highlight the importance of standardising hand sampling on a bunch when testing fruit susceptibility to crown rot. They also show that hand removal in the field has advantages in the context of integrated pest management, making it possible to reduce fruit susceptibility to crown rot while increasing fruit size. [less ▲]

Detailed reference viewed: 28 (7 ULg)
See detailHandboek Licentieovereenkomsten
Vanbrabant, Bernard ULg; Van Couter, Yves

Book published by Larcier (2008)

Het Handboek Licentieovereenkomsten schetst op een bevattelijke wijze het Belgisch juridisch kader dat gemeenschappelijk is aan de overeenkomsten tot gebruik van intellectuele eigendomsrechten. Waar ... [more ▼]

Het Handboek Licentieovereenkomsten schetst op een bevattelijke wijze het Belgisch juridisch kader dat gemeenschappelijk is aan de overeenkomsten tot gebruik van intellectuele eigendomsrechten. Waar aangewezen wordt de aandacht gevestigd op de specificiek regelgeving die, afhankelijk van het betrokken type van intellectuele eigendom, van toepassing is op een licentieovereenkomst. In het Eerste Deel van het Handboek komen de burgerrechtelijke aspecten aan bod: na de definiëring en de bespreking van de verschillende types licentieovereenkomsten, wordt in het bijzonder aandacht besteed aan het sluiten, de uitlegging, de uitvoering, de overdracht en de uitdoving van de licentieovereenkomst. In het tweede Deel komt de verhouding tussen de exploitatie van de intellectuele eigendom (de licentieovereenkomst) en het mededingingsrecht aan bod. Na enkele inleidende overwegingen volgt de toetsing van de licentieovereenkomst aan de artikelen 81 en 82 EG. Daar een goed functioneren van de Interne Markt één van de objectieven van het mededingingsrecht is, wordt tenslotte de verhouding tussen de licentieovereenkomst en die Interne Markt, het vrij verkeer van goederen binnen de Europese Economische Ruimte, behandeld. [less ▲]

Detailed reference viewed: 76 (3 ULg)
Full Text
Peer Reviewed
See detailHandheld modern computer brings new features to portable X-ray fluorescence coating thickness measurement device
Carapelle, Alain ULg; Defise, Jean-Marc ULg; Strivay, David ULg et al

in Computer Physics Communications (2011), 182(6), 1304-1306

Detailed reference viewed: 33 (7 ULg)
See detailLes handicapés, parlons-en!.....
Giot, Bernadette ULg; Mainguet, Christine ULg; Krol, P. et al

Book (1987)

Detailed reference viewed: 11 (0 ULg)
See detailHandicapped or different ? Symposium conclusions
De Landsheere, Gilbert ULg

in Information Bulletin (1974, April), 1

This summary paper of the Educational Research Symposium on the "Socio-Culturally Handicapped" details the major themes of the conference, and lists recommendations for further involvement for the Council ... [more ▼]

This summary paper of the Educational Research Symposium on the "Socio-Culturally Handicapped" details the major themes of the conference, and lists recommendations for further involvement for the Council of Europe in this area. (EH) [less ▲]

Detailed reference viewed: 5 (2 ULg)
See detailHandling complex risks issues in the domain of environment and health - SCOPE
Torfs, Rudi; Zwetkoff, Catherine ULg; Fallon, Catherine ULg et al

Report (2011)

This research report has its origin in the notion that classical risk assessment paradigms no longer suffice to deal with complex, uncertain and ambiguous risks. Risk assessment was developed as a ... [more ▼]

This research report has its origin in the notion that classical risk assessment paradigms no longer suffice to deal with complex, uncertain and ambiguous risks. Risk assessment was developed as a scientific tool to tackle uncertain consequences of human activities by organizing, evaluating, integrating and presenting scientific information to inform decision-making. Over the years, this type of risk assessment has proved effective in protecting public health and the environment from major environmental hazards with high relative risks. In the modern „risk society‟ classical risk assessment fails to handle complex risks characterized by radical uncertainty and a plurality of legitimate perspectives and values. Public authorities have to deal with issues/risks were facts are uncertain and values are contested. To answer to the increased demands of policymakers and the public for guidance on risk management new processes for the governance of these risks need to be developed. Weberian bureaucratic structures and forms of cooperation are working in a logic of specialisation of work, where distribution of information and knowledge, structures of decisions and allocation of responsibilities are organised ab initio in a stable organisational frame. Such a structure is not capable of resisting to the emergence of new risks which are often not identified as such at start and require a more integrative form of assessment, integrating inter-disciplinary collaboration on a specific policy problem that is complex, uncertain, perhaps unlimited in temporal and spatial scale, and interlinked with other phenomena. If the frame of reflexivity (Beck, 2003) is adopted, we thus have to recognise that a global mastering of these risks is not possible. What is now requested is the settlement of conditions for another type of open debate. Experiments in new forms of public participation in the management of technological developments (like e.g. citizen panels on long-term storage of nuclear waste1, or on cars and health2) already inspired the public administrators in their search for new procedural forms of decision making in areas of uncertainty. For a certain category of risks inclusion of the public, next to industrial stakeholders, organised environmental interest groups and governmental agencies and administrations is warranted, to integrate different opinions and values and to develop adequate policies. Network governance should be developed, where stakeholders are invited to speak up and where power structures are reconsidered and flattened. Here the authorities are recommended to exercise their capacities not as a centre of knowledge and top-down decision, but as a facilitator for communication and collaboration within networking structures, mobilising numerous experts and stakeholders, including the population itself (Gilbert, 2002), to develop new options which are socially acceptable and technically efficient (Fallon et al., 2008a & b). This requires a different mindset where the plurality of frames and fluidity of boundaries; the need for contextualisation; the construction of unstable temporary networks, the plurality of rationalities and the inherent uncertainties, social and technical (Callon, 1986) of the issues considered. As uncertainties are recognised, scientists are not anymore expected to close the controversy but rather to contribute to the technical quality of the process. The public decision-making process (DMP) should be designed to organise the conditions for an optimal tradeoff between scientific soundness and social acceptability of decisions, in a context where the precautionary principle is relevant. The key issue, framing or “structuring the research questions”, is a method for deciding how to manage scientific uncertainty. From literature review and past studies, we posit that a better quality DMP could be achieved by using tools for an integrated and comparative risk assessment and management. These approaches rely on interdisciplinary risk assessment – relevant soft and hard sciences are engaged together into the knowledge production process rather than mobilized side by side. Concretely, it involves designing the steps or sequences of the process and selecting/developing/adapting risk assessment and management tools. More specific, within the environment and health arena there is limited experience with these new concepts of integrated assessments (Briggs, 2008). Therefore case studies on various environment and health issues were performed to evaluate current integrated risk assessment practices, multi-level precautionary approaches and communication of complex risks. Different tools as Delphi, scenario workshop, etc. were used to analyse the issues at stake. The development of an integrated approach in risk assessment requires cooperation across policy domains and hierarchical structures. In the field of air pollution a science-policy workshop confirmed that in the domain of air quality policy, public servants communicate well with researchers from scientific institutions. The protagonists in Flemish air quality policy have a common scientific background and are technical experts. This observation puts into question a common discourse postulating that there is a „communication problem' or 'gap' between 'researchers' and 'policymakers'. This discourse as a description of a state of affairs does not suit empirical reality, and needs to be reformulated in more precise terms. If there is a communication gap, it is not to be situated between public administration („policymakers‟) and researchers („scientists‟), who share the same overall concerns, but between public administrations and ministerial cabinets. The analysis of risks related to electromagnetic fields (EMF), showed how the precautionary principle is reinterpreted differently at each different political level (European, Belgian, Wallonia, Regional) in order to better integrate the local institutional and political environment. In most cases, when this principle is put at the foreground, its use is mainly symbolic and incantatory. When implementing policies it does not seem to respond to some precautionary approach, but rather to the institutional dynamics which characterise each political level. We observed the reinforcement of the European role in the field of health & environment: in attempts to underline institutional cooperation at the federal level in Belgium and to reinforce the authority of the regional government on the Walloon territory. From this case study it is learnt that the new deliberative spaces to be developed should not be embedded in the dominant institutional structures. A structure such as promoted in the wake of "Technology assessment" (Delvenne, 2011) is capable of conciliating production of knowledge and uncertainties (the science pole) with the plurality of social perceptions (the civic pole) and the specific dynamics of the relevant polity (the political pole). New deliberative spaces should be capable of developing the basis for integrated and comparative approach for emerging issues with due attention to its political and institutional dimensions, while maintaining enough distance with the dominant frames and logics. Recently the Flemish administration on Environment, Nature & Energy proposed a note (framework) to deal with uncertain risks. The proposed framework will be tested in a pilot study for potential risks related to non-ionising electromagnetic radiation, and can later be extended to other risks. In a case study on Bisphenol-A (BPA), multi-level political communication was analysed. Political decisions were taken without socio-technical debate (Callon, 1986). The BPA issue was not very high on the social or political agenda in Belgium. There was no crisis, no strong pressure form NGO's. The question was managed first by the European authorities (EFSA & European Commission). The Belgian institutions were waiting for the European position. As the political decision did not encounter a strong contestation from the industry, this was an easy step for the political authorities, in Belgium and at the European level, to symbolically address the issue while avoiding considering the real uncertainties. When the decision was taken to ban the use of BPA in polycarbonate baby bottles, it was a political decision taken with the support of the scientific bodies (Superior Health Council) but without being embedded in any social debate (what about risks related to the chemicals which may substitute BPA?). It meant that the whole of uncertainties on the extent of risks related to the multiple exposures to different endocrine disruptors could not be put at the foreground in a public socio-technical debate. These case studies on the interplay with science, policy and stakeholders, on the framing of an environmental health policy problem, and on the management of complex risks (air pollution, EMF, BPA) contribute to recommendations on their governance. The question then becomes: is it possible to organize a precautionary decision making process to deal with different legitimate frames and the necessary trade-offs when considering policy alternatives? Concretely it is advised to pay attention to the role of a focal point in the process, potentially taken up by public administrations, to the co-production, availability and organisation of knowledge and information, and to the progress of the process. Above all it is important to set up a platform for issue framing and problem definition to highlight key factors that need to be assessed: - Examine the policy and stakeholder learning network related to a specific issue, with special attention to policy domains that are affected by or are affecting the environmental and health issue at stake. Specify who has interests in the issue and who should be involved. An efficient stakeholder network analysis is important for the further progress of the DMP. define who is allowed to take part in the process across different policy areas - Examine the information database before setting up a more integrative approach, both from a scientific (including uncertainties) and technical (alternatives, CBA analysis) point of view and from the side of concerned stakeholders. Policy makers acquire information from different inputs from science, stakeholder organisations, socio-economic actors and the public at large, as well as from administrations and staff members, and are conscious of the structural and constitutional constraints. It is clear that a balanced process of information gathering that is transparent, contributes to better decision making. - Initiate and manage the process: find out who will carry the process, set up a series of interactions between administrations, between administrations and cabinets, between administrations and research, between administrations, research and the public. Usable and meaningful available information on the issue should be communicated clearly to all stakeholders. It is innovative to look at how stakeholders increase their knowledge through different inputs and through communication, information and interaction. - Iterate where needed: information gained in one dialogue should be fed back into other fora. An equilibrium between acceptability – tolerability – uncertainty should be established. - Move forward / conclude. In the total policy cycle the conclusion or decision may be revised, when (1) monitoring of implementation and following evaluation is considered as negative; (2) new knowledge / experience / issues have to take into account. - Ensure an efficient and socially appropriate allocation of the resources and an adequate management of residual risks. Last but not least, in a precautionary approach it is also required, to contribute to the public trust in the decision making process and to construct social acceptance of the final decision. Generally, a precautionary decision making process should be considered as a double-pronged learning dynamics: on one side, the authorities are required to better take into account the multiple frames which abound in our pluralist societies when organising the conditions of political trade-offs for the governance of risks. On the other side, the citizens should have the possibility to, not only understand, but also adopt the decision and its consequences and to conform to its implementation. It is important to develop specific communication processes to successfully implement these two faces of a precautionary approach in the governance of risks, while ensuring this dual learning process. New procedures are currently developed which could support the communication dynamics for promoting multiple frames and comparing openly different alternatives (e.g. open process workshop; atelier scenarios; Delphi). [less ▲]

Detailed reference viewed: 84 (17 ULg)
Full Text
See detailHandling Emerging Issues on the Science/Policy Interface
Hendrickx, Kim ULg

Scientific conference (2011, April 26)

Detailed reference viewed: 15 (6 ULg)
Peer Reviewed
See detailHandling infinite temporal data
Kabanza, Froduald; Stevenne, Jean-Marc; Wolper, Pierre ULg

in Journal of Computer & System Sciences (1995), 51(1), 3--17

In this paper, we present a powerful framework for describing, storing, and reasoning about infinite temporal information. This framework is an extension of classical relational databases. It represents ... [more ▼]

In this paper, we present a powerful framework for describing, storing, and reasoning about infinite temporal information. This framework is an extension of classical relational databases. It represents infinite temporal information by generalized tuples defined by linear repeating points and constraints on these points. We characterize the expressiveness of these generalized relations in terms of predicates definable in Presburger arithmetic. Next, we prove that relations formed from generalized tuples are closed under the operations of relational algebra and provide complexity results for the evaluation of first-order queries. [less ▲]

Detailed reference viewed: 9 (0 ULg)