4,540 research outputs found

    Integrated Structure and Semantics for Reo Connectors and Petri Nets

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    In this paper, we present an integrated structural and behavioral model of Reo connectors and Petri nets, allowing a direct comparison of the two concurrency models. For this purpose, we introduce a notion of connectors which consist of a number of interconnected, user-defined primitives with fixed behavior. While the structure of connectors resembles hypergraphs, their semantics is given in terms of so-called port automata. We define both models in a categorical setting where composition operations can be elegantly defined and integrated. Specifically, we formalize structural gluings of connectors as pushouts, and joins of port automata as pullbacks. We then define a semantical functor from the connector to the port automata category which preserves this composition. We further show how to encode Reo connectors and Petri nets into this model and indicate applications to dynamic reconfigurations modeled using double pushout graph transformation

    Design and implementation of a behaviorally typed programming system for web services

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    Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do Grau de Mestre em Engenharia Informática.The growing use of the Internet as a global infrastructure for communication between distributed applications is leading to the development of a considerable amount of technologies to ease the deployment, description and data exchange among services and thus improve their interoperability. There is also a growing interest in the use of the “software as a service” business model where a software vendor develops and hosts applications to be used by its clients over the Internet. The use of these Web Services is provided through an API describing the interface of the service that can hide how the service provider hosts the application. This approach allows for the creation of an abstraction layer that offers additional capabilities without increasing the maintenance cost usually linked to the management of those machines (like software and hardware updates or just application/system configuration). However, the main tools provided by the standards and existing technology to combine these services usually only account for limited automatic verification techniques (based on standard signature checking of methods in interface descriptions) and thus relying the behavioral compatibility among services to the programmer. The programmer then becomes dependent on the quality of the documentation and the development time available to manually (and without formal guarantees) assure the correctness of the code. In this thesis, we propose a behavioral type system, in the context of yak, a prototype scripting language for web services, that enhances traditional typecheckers by allowing to statically check the correct usage of services (as remote or local objects). Our language uses behavioral annotations in the protocol descriptions, similar to regular expressions, that are translated to deterministic finite automatons during the typechecking phase. The intent of this work is to ease the creation and deployment of Web Services by providing a friendly integration of behavioral type concepts within a practical programming language, so to make the use of these services (with behavioral descriptions) transparent and effortless to the programmer. We also provide a full implementation of the interpreter, behavioral typechecker and run-time support system for the yak language, that may be used to develop prototypical systems and experiment with web services and behavioral type

    Toward a Conceptualization of Mixed Methods Phenomenological Research

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    Increasingly, researchers are recognizing the benefits of expanding research designs that are rooted in one tradition (i.e., monomethod design) into a design that incorporates or interfaces with the other tradition. The flexibility of phenomenologically driven methods provides one such example. Indeed, phenomenological research methods work extremely well as a component of mixed methods research approaches. However, to date, a mixed methods version of phenomenological research has not been formally conceptualized. Thus, the purpose of this article is twofold. First, we provide a philosophical justification for using what we call mixed methods phenomenological research (MMPR). Second, we provide examples of MMPR in practice to underline a number of potential models for MMPR that can practically be used in future research

    Two-person neuroscience and naturalistic social communication: The role of language and linguistic variables in brain-coupling research

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    Social cognitive neuroscience (SCN) seeks to understand the brain mechanisms through which we comprehend others? emotions and intentions in order to react accordingly. For decades, SCN has explored relevant domains by exposing individual participants to predesigned stimuli and asking them to judge their social (e.g., emotional) content. Subjects are thus reduced to detached observers of situations that they play no active role in. However, the core of our social experience is construed through real-time interactions requiring the active negotiation of information with other people. To gain more relevant insights into the workings of the social brain, the incipient field of two-person neuroscience (2PN) advocates the study of brain-to-brain coupling through multi-participant experiments. In this paper, we argue that the study of online language-based communication constitutes a cornerstone of 2PN. First, we review preliminary evidence illustrating how verbal interaction may shed light on the social brain. Second, we advance methodological recommendations to design experiments within language-based 2PN. Finally, we formulate outstanding questions for future research.Fil: García, Adolfo Martín. Universidad Nacional de Córdoba. Facultad de Lenguas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva. Fundación Favaloro. Instituto de Neurociencia Cognitiva; Argentina. Universidad Diego Portales; ChileFil: Ibanez Barassi, Agustin Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva. Fundación Favaloro. Instituto de Neurociencia Cognitiva; Argentina. Universidad Diego Portales; Chile. Universidad Autónoma del Caribe; Colombia. Australian Research Council Centre of Excellence in Cognition and its Disorders; Australi

    Interactions between sentence comprehension and concurrent action: The role of movement effects and timing

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    Embodied approaches to language comprehension suggest that we understand sentences by using our perception and action systems for simulating their contents. In line with this assumption, the action-sentence compatibility effect (ACE) shows that sensibility judgments for sentences are faster when the direction of the described action matches the direction of the response movement. The aim of this thesis was to investigate whether this compatibility is effective between sentence direction and movement direction or between sentence direction and the direction of the movement effect. To this end, movements were dissociated from their effects in several experiments. Participants indicated whether sentences describing transfer actions toward or away from the body are sensible or not by producing a movement effect on a screen at a location near the body or far from the body. These movement effects were achieved by moving the hand from a middle button to a near or far button, i.e., toward the body or away from the body. In one condition, a movement effect resulted from pressing the button whose location corresponded with the location of the effect. Crucially for the above research question, there was another condition in which an action effect resulted from pressing the button at the opposite location. Since in the first series of experiments, the ACE turned out to be unreliable and in part seemed to be reversed, it was difficult to address the initial question. Therefore, a second series of experiments additionally investigated the role of timing between response preparation and sentence comprehension as a potential cause of the negative ACE. Results showed a positive ACE when the same directional feature was concurrently activated within the two processes, leading to priming between them. A negative ACE appeared when the directional feature was already bound into the sentence representation and thus was less accessible when needed for response preparation. In both cases, the ACE was related to the movement effect. These results suggest that the ACE occurs on the higher level of cognitive representations referring to distal information

    Multimodal Interaction Recognition Mechanism by Using Midas Featured By Data-Level and Decision-Level Fusion

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    Natural User Interfaces (NUI's) dealing with gestures is an alternative of traditional input devices on multi-touch panels. Rate of growth in the Sensor technology has increased the use of multiple sensors to deal with various monitoring and compatibility issues of machines. Research on data-level fusion models requires more focus on the fusion of multiple degradation-based sensor data. Midas, a novel declarative language to express multimodal interaction patterns has come up with the idea of developers required patterns description by employing multi-model interaction mechanism. The language as a base interface deals with minimum complexity issues like controlling inversion and intermediary states by means of data fusion, data processing and data selection provisioning high-level programming abstractions
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