Search results for "Mathematical logic"
showing 10 items of 394 documents
Converging Analysis of the Concept of Strategic Group in the Spanish Lighting Industry
2008
Strategic group literature does not seem to offer strong enough theoretical bases to state the very existence of strategic groups and their effects on firm’s conduct and performance. The empirical validation of the existence of strategic groups has been usually done trying to contrast their predictive validity in relation to performance, obtaining conflicting evidence. Other papers have decided to contrast the convergent validity of the strategic group concept using different definitions and measures of this construct. Our work belongs to the second type of studies. It tries to make progress in the development of a theoretical model, able to state the industry features which affect the prob…
Jet Engine Design Optimization Using a Knowledge-Based Master Model
2012
This paper presents a preliminary design optimization study of a jet engine structure using a knowledge-based master modeling approach. The objective function is derived based on input-output relationships of a cost-performance model, where specific fuel consumption, pressure loss and direct cost are considered. The advantage of this problem formulation is that it entails a single composite objective function that takes into account mass, structural characteristics, dynamic response and translates them to a direct operational cost function to be minimized. A fan-blade-off scenario is considered as the loading case in this paper. The loss of one fan blade during nominal operation causes a ro…
Does the mastery of center-embedded linguistic structures distinguish humans from nonhuman primates?
2005
In a recentScience article, Fitch and Hauser (2004; hereafter, F&H) claimed to have demonstrated that cotton-top tamarins fail to learn an artificial language produced by a phrase structure grammar (Chomsky, 1957) generating center-embedded sentences, whereas adult humans easily learn such a language. We report an experiment replicating the results of F&H in humans but also showing that subjects learned the language without exploiting in any way the center-embedded structure. When the procedure was modified to make the processing of this structure mandatory, the subjects no longer showed evidence of learning. We propose a simple interpretation for the difference in performance observed in F…
CheS-Mapper - Chemical Space Mapping and Visualization in 3D
2012
Abstract Analyzing chemical datasets is a challenging task for scientific researchers in the field of chemoinformatics. It is important, yet difficult to understand the relationship between the structure of chemical compounds, their physico-chemical properties, and biological or toxic effects. To that respect, visualization tools can help to better comprehend the underlying correlations. Our recently developed 3D molecular viewer CheS-Mapper (Chemical Space Mapper) divides large datasets into clusters of similar compounds and consequently arranges them in 3D space, such that their spatial proximity reflects their similarity. The user can indirectly determine similarity, by selecting which f…
Disentangling the complexity of low complexity proteins
2020
Abstract There are multiple definitions for low complexity regions (LCRs) in protein sequences, with all of them broadly considering LCRs as regions with fewer amino acid types compared to an average composition. Following this view, LCRs can also be defined as regions showing composition bias. In this critical review, we focus on the definition of sequence complexity of LCRs and their connection with structure. We present statistics and methodological approaches that measure low complexity (LC) and related sequence properties. Composition bias is often associated with LC and disorder, but repeats, while compositionally biased, might also induce ordered structures. We illustrate this dichot…
Formations of finite monoids and formal languages: Eilenberg’s variety theorem revisited
2014
International audience; We present an extension of Eilenberg's variety theorem, a well-known result connecting algebra to formal languages. We prove that there is a bijective correspondence between formations of finite monoids and certain classes of languages, the formations of languages. Our result permits to treat classes of finite monoids which are not necessarily closed under taking submonoids, contrary to the original theory. We also prove a similar result for ordered monoids.; Nous présentons une extension du théorème des variétés d'Eilenberg, un résultat célèbre reliant l'algèbre à la théorie des langages formels. Nous montrons qu'il existe une correspondance bijective entre les form…
Measuring and Evaluating Intergenerational Mobility: Evidence from Students’ Questionnaires
2005
Three fundamental ideas in the study of intergenerational mobility are those of structural mobility, origin independence and rank reversal. We review the theoretical literature focused on the three ideas and present evidence from a questionnaire designed to test students’ views regarding the different notions. The questionnaire is conducted under both a “measurement” and an “evaluation” frame; it uses questions involving both verbal statements of the principles tested and pairwise comparisons of simple hypothetical mobility situations; for the latter exercise, the questionnaire introduces a new intuitive display based on mobility trees. The evidence provides various results: most notably, o…
A Joint Reading of Positional and Relational Goods
2012
Both relational and positional goods are based upon an idea of joint consumption – though with opposite signs. Indeed, in both cases, individuals’ consumption choices take into account not only the individuals themselves, but others, as well. Given that relational goods provide a form of identity to their consumers, we show that a certain degree of positionality emerges within the consumption of relational goods. Analogously, except in a two-agent context, each positional good also has a relational component. What emerges is a complex structure of economic outcomes based on both relational and positional motives.
Schema-Backed Visual Queries over Europeana and Other Linked Data Resources
2021
We describe and demonstrate the process of extracting a data-driven schema of the Europeana cultural heritage Linked data resource (with actual data classes, properties and their connections, and cardinalities) and application of the extracted schema to create a visual query environment over Europeana. The extracted schema information allows generating SHACL data shapes describing the actual data endpoint structure. The schema extraction process can be applied also to other data endpoints with a moderate data schema size and a potentially large data triple count, as e.g., British National Bibliography Linked data resource.
Interactive Learning Environments (ILEs) as Effective Tools for Teaching Social Sciences
2016
Schoolteachers could enhance learning in social science courses by using teaching tools that favour a methodological approach focused on the topics' basic structure rather than on facts. An innovative system dynamics social-based ILE built with a social constructivist approach is presented here. The pedagogical futures of this ILE are then analysed. The effective impact of different instructional approaches inspired by social-based ILEs on student learning outcomes is also discussed. The ILE and the related inquiry-based instructional approach seem to help students understand fundamental concepts more easily, thus making the topic more comprehensible and helping students place the social fa…