Semantic Module Research Articles

Ontology matching for dynamic publication in semantic portals

Semantic portals are characterized for storing and structuring content according to specific domain ontologies. This content is represented through ontological languages, which enable not only adding semantic value to information treatment, but also inferring new knowledge from it. Publication in a semantic portal is typically done by instantiating its ontology, and this is often performed manually or through the use of specific forms. However, in order to keep portals constantly up-to-date, it is necessary to provide means for a more dynamic publication, integrating the portal content with information retrieved from different ontology-based sites on the same or on complementary domains. Reusing information from different ontologies requires specific and efficient mechanisms to align them, taking into account syntactical and semantical conflicts. This paper proposes an extension of the Crosi Mapping System, a matching mechanism which calculates similarities between ontologies. Some of its original algorithms have been enriched with additional functionality. This extension, named e-CMS, has been evaluated using the OAEI ontology alignment benchmark, and results show an increase of 69% in alignment precision when compared to the CMS original version. In order to illustrate its use, the e-CMS strategy was applied to SiGePoS, a System for Generating Semantic Portals. The semantic module, one of the system components, implements the alignment mechanism between ontologies, which is performed by the e-CMS.

Challenging Systems of Lexical Representation

The aim of this paper is to offer an overview of some of the most relevant heuristic parameters that have been used for the organization of the lexicon in a representative sample of formal, functional and cognitive models. In connection with this, we address the following theoretical issues: (i) the nature of the metalanguage that should be used as part of a lexical representation theory; (ii) the actual scope of the representation, that is, whether a lexical entry should only capture those aspects of the word that have syntactic visibility or should go beyond that and include richer semantic decompositions together with encyclopedic information; (iii) the type of formalism involved in the description of meaning for the design of robust technological applications. In the light of this discussion, we will present a sample model of lexical description called lexical templates.Lexical templates draw insights both from models with a stronger syntactic orientation (e.g. RRG’s logical structures) and from accounts where semantic description is more important (e.g. Frame Semantics). A lexical template consists of two different modules both of which are based on a universal abstract semantic metalanguage. The resulting templates have two parts: (i) the semantic module which makes use of lexical functions and (ii) the logical representation or Aktionsart module, which is inspired in the inventory of logical structures as posited in RRG. Worthy of note is also the fact that this paper lays out the foundations towards a reconversion of the inventory of lexical functions in terms of Pustejovsky's qualiae. Thus, lexical templates are now built on the basis of a new, more robust formalism with greater explanatory and representational capacity.

Repetition suppression in occipital–temporal visual areas is modulated by physical rather than semantic features of objects

Functional magnetic-resonance imaging was used to identify areas involved in naming objects and to examine which of these areas adapted to either physical or semantics features of objects. We presented successive pairs of objects that were either the same exemplar of an object, different exemplars of that object, or different objects. By controlling for differences in physical features between pairs of different exemplars and different objects, visual areas in the occipital–temporal cortex were subject to repetition suppression when the same exemplars of an object were repeated, but not when different exemplars of an object were repeated. This was true independent of whether or not participants named objects. Repetition suppression in visual areas appeared therefore bound to physical features. Nevertheless, repetition suppression for physical features was greater in left visual areas when objects were named, suggesting that naming, known to depend on mechanisms in the left hemisphere, may induce greater attentional modulation in the left than in the right visual areas. Taken together, we propose that the difference between our findings and those of earlier studies that report semantic influences can be explained by the failure of those studies to control for differences in the appearance of different exemplars. Left frontal areas showed repetition suppression when either the same or different exemplars of an object were repeated, but only when participants named objects. These results suggest that visual areas process information about physical features without semantic modulation by higher-order areas, and that left frontal areas process semantic features, but the engagement of these processes is task modulated.

Early MEG Activation Dynamics in the Left Temporal and Inferior Frontal Cortex Reflect Semantic Context Integration

Traditional views link semantic context integration to neurophysiological activity at 300-500 msec. To study possible early dynamics related to semantic context integration, we recorded, in passive oddball paradigm, magnetic evoked responses to spoken word pairs, the second word being either congruent or incongruent with the first one. The same experimental words were placed in orthogonally varied context, thus providing a strict control for any effects of acoustic, phonological, and psycholinguistic stimulus features. Responses to the same critical words were obtained also outside of semantic context. We found that regardless of their acoustic features, semantically incongruent stimuli elicited a brain response already at approximately 115 msec after the critical word onset. The same words did not produce such deflection in semantically legal context. The responses were maximal at left temporal and inferior frontal cortical sites, which was also confirmed by distributed current source analysis. The left temporal activation preceded the frontal one by approximately 16 msec. No late response dynamics (>350 msec) were found that would reflect the semantic modulation in this nonattend passive design, indicating the possible role of attention in generating the later responses. Our results suggest that the earliest brain processes of semantic context integration can occur at approximately 100 msec after the onset of spoken words in the left inferior frontal and superior temporal cortex.

Information Seeking Spoken Dialogue Systems— Part I: Semantics and Pragmatics

In this paper, the semantic and pragmatic modules of a spoken dialogue system development platform are presented and evaluated. The main goal of this research is to create spoken dialogue system modules that are portable across applications domains and interaction modalities. We propose a hierarchical semantic representation that encodes all information supplied by the user over multiple dialogue turns and can efficiently represent and be used to argue with ambiguous or conflicting information. Implicit in this semantic representation is a pragmatic module, consisting of context tracking, pragmatic analysis and pragmatic scoring submodules, which computes pragmatic confidence scores for all system beliefs. These pragmatic scores are obtained by combining semantic and pragmatic evidence from the various sub-modules (taking into account the modality of input) and are used to rank-order attribute-value pairs in the semantic representation, as well as identifying and resolving ambiguities. These modules were implemented and evaluated within a travel reservation dialogue system under the auspices of the DARPA Communicator project, as well as for a movie information application. Formal evaluation of the semantic and pragmatic modules has shown that by incorporating pragmatic analysis and scoring, the quality of the system improves for over 20% of the dialogue fragments examined

Syntactic and Semantic Modulation of Neural Activity during Auditory Sentence Comprehension

In previous functional neuroimaging studies, left anterior temporal and temporal-parietal areas responded more strongly to sentences than to randomly ordered lists of words. The smaller response for word lists could be explained by either (1) less activation of syntactic processes due to the absence of syntactic structure in the random word lists or (2) less activation of semantic processes resulting from failure to combine the content words into a global meaning. To test these two explanations, we conducted a functional magnetic resonance imaging study in which word order and combinatorial word meaning were independently manipulated during auditory comprehension. Subjects heard six different stimuli: normal sentences, semantically incongruent sentences in which content words were randomly replaced with other content words, pseudoword sentences, and versions of these three sentence types in which word order was randomized to remove syntactic structure. Effects of syntactic structure (greater activation to sentences than to word lists) were observed in the left anterior superior temporal sulcus and left angular gyrus. Semantic effects (greater activation to semantically congruent stimuli than either incongruent or pseudoword stimuli) were seen in widespread, bilateral temporal lobe areas and the angular gyrus. Of the two regions that responded to syntactic structure, the angular gyrus showed a greater response to semantic structure, suggesting that reduced activation for word lists in this area is related to a disruption in semantic processing. The anterior temporal lobe, on the other hand, was relatively insensitive to manipulations of semantic structure, suggesting that syntactic information plays a greater role in driving activation in this area.

Morphed facial expressions elicited a N400 ERP effect: A domain‐specific semantic module?

Previous studies have revealed that decoding of facial expressions is a specific component of face comprehension and that semantic information might be processed separately from the basic stage of face perception. In order to explore event-related potentials (ERPs) related to recognition of facial expressions and the effect of the semantic content of the stimulus, we analyzed 20 normal subjects. Faces with three prototypical emotional expressions (fear, happiness, and sadness) and with three morphed expressions were presented in random order. The neutral stimuli represented the control condition. Whereas ERP profiles were similar with respect to an early negative ERP (N170), differences in peak amplitude were observed later between incongruous (morphed) expressions and congruous (prototypical) ones. In fact, the results demonstrated that the emotional morphed faces elicited a negative peak at about 360 ms, mainly distributed over the posterior site. The electrophysiological activity observed may represent a specific cognitive process underlying decoding of facial expressions in case of semantic anomaly detection. The evidence is in favor of the similarity of this negative deflection with the N400 ERP effect elicited in linguistic tasks. A domain-specific semantic module is proposed to explain these results.

Selectional restrictions in HPSG: I'll eat my hat!

This contribution is concerned with integrating the phenomenon of selectional restrictions in HPSG. Firstly, the question of treating selectional restrictions purely in the semantic module is tackled, as there are some contextual (or pragmatic) influences, which can repair the ill-formedness of violated selectional restrictions. Secondly, we present existing approaches to selectional restrictions within the framework and, lastly, make our own proposal which describes the subject as part of the semantics-pragmatics interface. In particular, we show how a semantic ontology can be integrated.

Wieviel Logik braucht die Semantik? Ein Problem (nicht nur) für die wahrheitstheoretische Semantik

The present paper is a closer examination of that version of so-called which is developed by Larson and Segal (1995). Generally, the claim of truth-functional semantics is that the semantic meta-theory of an object language is exhausted by an adequate theory of truth for this language. Here the measure of adequacy is Tarski's celebrated criterion T, which requires for each object language sentence A a sentence (of a special form) stating the truth-conditions for A. Larson and Segal combine the truth-theoretic view on semantics with a modular approach to linguistics. They stipulate a semantic in which the truth-conditions for the object language sentences are derived. Since the module is, according to Larson and Segal, separated from the semantic module, these derivations can only make quite limited use of logical means. In the present paper I shall demonstrate that even in one of the most primitive sample theories which Larson and Segal develop in their monography, it is necessary to use much more of logic than they are ready to admit. Finally, I will set up and comment on a general formulation of the problem involved here, namely: how much logic is necessary in an adequate semantics.

The semantic organisation of proper nouns: the case of people and brand names

We describe the performance of a patient (AZ) with a semantic refractory access disorder on a series of experiments probing comprehension of two broad proper noun categories, namely person names and brand names. By inducing and manipulating the semantic relatedness effects which are commonly observed in semantic refractory access patients, we demonstrate that famous person knowledge is primarily organised by occupation, whilst knowledge of brands is organised by product type. For instance, we show that AZ has significantly greater difficulty identifying a famous person from among distractor personalities who have the same occupation (e.g. composers: Beethoven, Mozart, Handel, and Bach) than those who have different occupations (e.g. Beethoven, Picasso, Shakespeare, and Jefferson). We also show that such semantic relatedness effects do not occur when stimuli are grouped by another variable such as nationality. We argue that these semantic distance effects reflect the greater build-up of refractoriness among concepts which are supported by shared neural circuitry. In psychological space, it seems natural that these individuals should be classified in this way. The strength of our findings lie in the fact that this organisation of psychological space is mirrored by neural organisation. Thus, we report a previously undocumented degree of fine-grain organisation within conceptual knowledge of these classes of proper nouns. We also interpret our data as providing the strongest empirical support to date for the semantic module of cognitive models of person recognition.

Two types of wh-adverbials

This paper presents cross-linguistic arguments for distinguishing between two types of wh-adverbials: causal how, causal why, and epistemic why pattern together in taking an IP scope, functioning as operators, whereas method how, manner how, and purpose why pattern together in taking a VP scope, functioning as predicates of underlying events. For the former group, there is always a cause-effect relation underpinning their syntactic distributions across languages, which is semantically realized as a causative predicate taking two events as its arguments, i.e., a cause event and an effect event. In a causal question, it is the cause event that is bound by the question operator; in a resultative question, the effect event is bound instead. For the latter group, they surface as conjuncts of main predicates in Tsou, which in turn argues for a neo-Davidsonian treatment of adjunct association in syntax (Parsons 1990). The fact that a conjunctive how can be construed as either a manner/method question or a resultative question in Tsou further argues for an independent semantic module in grammar in the vein of Culicover and Jackendoff (1997).

The architecture is not exactly parallel: Some modules are more equal than others

Despite its computational elegancy, Jackendoff's proposal to reconcile competing approaches by postulating a parallel architecture for phonological, syntactic, and semantic modules is disappointing. We argue that it is a pragmatic version of the leading module which Jackendoff would probably prefer, but which he does not explicitly acknowledge. This internal conflict leads to several shortcomings and even distortions of information presented in the book.

La doctrina del amor en Ibn Al-Arabí. Comentario del nombre divino Al-Wadd

Partiendo, de un lado, de la idea de que la especulacion es, para el gnostico, el espejo en el que se reflejan los misterios divinos, cuyo eco percibe a su vez la razon discursiva (que, por lo mismo, no puede quererse fuente ni de su metodo ni de su lenguaje), y partiendo, de otro, de la exploracion intralinguistica o gramatosofica emprendida (a partir de tales premisas) por el gnostico andalusi Ibn al-'ArabI, ofrecemos al lector una traduccion comentada de una breve seccion del penultimo capitulo de Las Revelaciones de La Meca, su principal obra. Nos centraremos, a tal fin, en las diferentes modulaciones morfologicas y semanticas de la raiz arabe W-D-D, que da lugar al Nombre divino al-Wadnd y que permite una original comprension de la realidad del amor, su genesis, sus diferentes estados, su caracter divino y sus funciones creadora, cosmologica y antropologica.

Co-operation of syntax and semantics in flexive languages

Abstract The idiosyncrasies of the fiexic Slavonic languages, such as the rich case system and complex morphology, entail a free word-order and require a specialized approach when parsed. We claim complex morphology is not the only disadvantage of the language. Augmented transition networks for Slovak are introduced, and their adequacy for Slovak and comparison to English networks are discussed. Further, we introduce briefly our concept of semantic analysis, based on a semantic case system, verb and noun valency frames. The phenomenon of nominalization is investigated. The central theme of this paper is the close communication of syntax and semantics. The sequentially working modules shift misinterpretations and ambiguities from one to another. This leads to combinatorial explosions and the loss of effectiveness. The communication between the syntactic and semantic modules enables the exclusion of some syntactically correct, but semantically nonsensical interpretations in early phases of sentence processi...