To support wireless-oriented services, a new generation of Web services called Mobile services (M-services) has emerged. M-services provide mobile users access to services through wireless networks. One of the important issues in M-service environment is how to discover and access M-services efficiently. In this dissertation, we propose time and power efficient access methods for M-services. We focus on methods for accessing broadcast based M-services from multiple wireless channels. We first discuss efficient access methods in data-oriented wireless broadcast systems. We then discuss how to extend current wireless broadcast systems to support simple M-services. We present a novel infrastructure that provides a multi-channel broadcast framework for mobile users to effectively discover and access composite M-services. Multi-channel algorithms are proposed for efficiently accessing composite services. We define a few semantics that have impact on access efficiency in the proposed infrastructure. We discuss semantic access to composite services. Broadcast channel organizations suitable for discovering and accessing composite services are proposed. We also derive analytical models for these channel organizations. To provide practical study for the proposed infrastructure and access methods, a testbed is developed for simulating accessing M-services in a broadcast-based environment. Extensive experiments have been conducted to study the proposed access methods and broadcast channel organizations. The experimental results are presented and discussed. / Ph. D.

Cette thèse se propose de spécifier la relation entre les structures motrices et celles du langage en tant que systèmes coopératifs dans la construction du sens. Bien qu'un grand nombre d'études aient mis en évidence que les structures motrices sont impliquées dans le traitement du langage, il est encore difficile de déterminer le rôle de ces structures dans la compréhension. Les théories dites «incarnées» et «désincarnées» débattent de la nature de la représentation du sens des mots en termes de la nécessité des structures motrices pour le langage, en négligeant le fait que les conditions de leur activation n’ont pas été décrites. Des recherches récentes soulignent l’importance de la prise en compte des contextes dans lesquels le langage recrute l'activité motrice. Néanmoins, cette tendance est en contradiction avec les présomptions implicites dans la recherche sur l’interaction langage-motricité, qui se basent sur le modèle «deux-étapes» du traitement sémantique et sur la perspective du «dictionnaire» de la représentation du sens lexical. Dans ce cadre, le traitement du sens des mots est pris comme un processus modulaire. Ce n'est qu'une fois ce processus accompli que le contexte peut influencer la signification. Ces présomptions ont biaisé le débat sur le rôle de l'activité motrice induite par le langage, qui se réduirait à la question de savoir si l'activation motrice doit être considérée comme faisant partie de l'accès lexico-sémantique ou comme résultat de la construction d’un modèle de situation. Or, un grand nombre de travaux ont mis en évidence que le traitement lexico-sémantique et le contexte sont interdépendants. Cette connaissance provenant de la psycholinguistique doit être explicitement intégrée à la recherche sur le rôle de l'activité motrice induite par le langage. Dans un effort pour porter le débat hors de la discussion «lexical vs. post-lexical», cette thèse vise à déterminer les conditions sous lesquelles les contextes linguistiques déclenchent l'activité motrice. Pour ce faire, nous avons testé un nouvel outil qui analyse en ligne les modulations de la force de préhension pendant que les participants écoutaient des mots cibles intégrés dans différents contextes. Nos résultats montrent que quand le mot cible était un verbe d'action de la main et que la phrase focalisait l'action (« John signe le contrat»), une augmentation de la force de préhension était observée dans la fenêtre temporelle associée à la récupération lexico-sémantique. Aucune augmentation de la force de préhension comparable n’a été détectée lorsque le même mot d'action était intégré dans des phrases négatives («John ne signe pas le contrat») ou dans des phrases dont le focus avait été déplacé vers l'état mental de l'agent («John veut signer le contrat») ... / The present dissertation was conducted in order to specify the relationship between motor and language structures as cooperative systems in lexical meaning construction. Specifically, this thesis aimed at deepening our understanding of how the linguistic context coordinates the recruitment of motor structures during lexical semantic processing. Although the involvement of motor activity in action-related language comprehension is now sufficiently documented, the specific role that motor structures play in action language processing is still unclear. “Embodied” and “disembodied” theories debate the nature of meaning representation in terms of the necessity of motor structures, neglecting the fact that the conditions of their activation during language processing are not well-described. Very recent research has begun to note the necessity of exploring the context under which words trigger modality-specific cortical activity. However, this trend is at odds with implicit theoretical assumptions that have been made in research on motor-language crosstalk, which are based on the “two-step” model of semantic processing and the “dictionary-like” view of lexical meaning representation. Within such framework, word meaning recognition is taken to proceed in a modular fashion. Only after this process has concluded is the context thought to exert its effects. These assumptions have biased the debate on the role of language induced motor activity. The discussion has been centered on whether motor activation should be considered an integral part of the lexical access process or taken as the result of an ensuing “higher order” operation (i.e., situation model construction). A large body of work evidences that lexical semantic processing and semantic context are far more integrated and interdependent. It seems crucial to integrate this knowledge gained from psycholinguistics into the research on the role of language induced motor activity. In an effort to liberate the debate from the “lexical vs. post-lexical” discussion, this thesis aimed at determining the conditions under which language triggers motor activity. To accomplish these objectives, we introduced a novel tool that analyzes on-line modulations of grip-force while participants listened to specific target words embedded within different types of contexts. Our results show that when the target word was a hand action verb and the sentence focus centered on that action (“John signs the contract”), an increase of grip force was observed in the temporal window classically associated with lexical semantic processing. No comparable increase in grip force was detected when the same action word was embedded in negative sentences (“John doesn’t sign the contract”) or in sentences which focus was shifted towards the agent’s mental state (“John wants to sign the contract”). Our results suggest that the presence of an action word in an ...

Current models of spoken word recognition have been predominantly based on studies of Indo-European languages. As a result, little is known about the recognition processes involved in the perception of tonal languages (e.g., Mandarin Chinese), and the role of lexical tone in speech perception. One view is that tonal languages are processed phonologically through individual segments, while another view is that they are processed lexically as a whole. Moreover, a recent study claimed to be the first to discover an early phonological processing stage in Mandarin (Huang et al., 2014). There seems to be a lack of investigations concerning tonal languages, as no clear conclusions have been made about the nature of tonal processes, or a model of spoken word recognition that best incorporates lexical tone. The current study addressed these issues by presenting 18 native Mandarin speakers with aural sentences with medial target words, which either matched or mismatched the preceding visually presented sentences with medial target words (e.g, 家 /jia1/ “home”). Violation conditions involved target words that differed in the following ways: tone violation, where only the tone was different (e.g., 价 /jia4/ “price”), onset violation, where only the onset was different (e.g., 虾 /xia1/ “shrimp”), and syllable violation, where both the tone and the onset were different (e.g., 糖 /tang2/ “candy”). We did not find evidence for an early phonological processing stage in Mandarin. Instead, our findings indicate that Mandarin syllables are processed incrementally through phonological segments and that lexical tone is strongly associated with semantic access. These results are discussed with respect to modifications for existing models in spoken word recognition to incorporate the processes involved with tonal language recognition. / Thesis / Master of Science (MSc)