João Ladislau Lopes

Towards a distributed architecture for context-aware mobile applications in UbiComp

The applications in Ubiquitous Computing (UbiComp) environments must be aware of their contexts of interest and adapt to changes in them. Thus, a major research challenge in the area of UbiComp is related to context awareness. Considering the high distribution, heterogeneity, dynamism, and mobility of ubiquitous environments, this paper presents an architectural model for context awareness, called EXEHDA-UC (Execution Environment for Highly Distributed Applications - Ubiquitous Context awareness). The proposal includes elements to support contextual data acquisition, actuation on the environment, and processing of contextual information. We consider that the main contribution of this work is an architecture that supports the managing of the acquisition, storage, and processing of context data, in a distributed way, independently of the application, in an autonomic and rule-based perspective. To assess the functionalities of the EXEHDA-UC, we present a case study, highlighting the prototypes developed, technologies employed, and tests realized.

A model for context awareness in Ubicomp

In this paper we present a view of EXEHDA middleware and a novel service created for dynamic adaptation. EXEHDA is service-oriented, adaptive and was conceived to support the execution of ubiquitous applications. The main concept in the proposed design for the middleware and for the application is context awareness expressed in an adaptive behavior. The middleware manages and implements the follow-me semantics for ubiquitous applications. This is also a key to provide functionality adapted to the constraints and unpredictability of the large-scale environment. EXEHDA provides services for distributed adaptive execution, context recognition, ubiquitous storage and access, and anonymous and asynchronous communications. To evaluate the proposed service we developed a case study, implementing an application in medical area. Analyzing the results we can see that the users found the application easy to use and usefulness for health workers at a hospital.

A Distributed Architecture for Supporting Context-Aware Applications in UbiComp

The applications in Ubiquitous Computing (UbiComp) environments must be aware of their contexts of interest and adapt to changes in them. Thus, a major research challenge in the area of UbiComp is related to context awareness. Considering the high distribution, heterogeneity, dynamism, and mobility of ubiquitous environments, this paper presents an architecture for context awareness, named UbiC (Ubiquitous Context awareness), which is integrated to EXEHDA middleware (Execution Environment for Highly Distributed Applications). We consider that the main contribution of this work is an architecture that enables the acquisition, storage, and processing of context data, in a distributed way, independently of the application, in a rule-based autonomic perspective, and with support to mobility. To assess the functionalities of the UbiC architecture, we present a case study, highlighting prototypes developed, technologies employed, and tests realized.

Managing adaptation in Ubicomp

In this paper we present a view of EXEHDA middleware and a novel service created for dynamic adaptation. EXEHDA is service-oriented, adaptive and was conceived to support the execution of ubiquitous applications. The main concept in the proposed design for the middleware and for the application is context awareness expressed in an adaptive behavior. The middleware manages and implements the follow-me semantics for ubiquitous applications. This is also a key to provide functionality adapted to the constraints and unpredictability of the large-scale environment. EXEHDA provides services for distributed adaptive execution, context recognition, ubiquitous storage and access, and anonymous and asynchronous communications. To evaluate the proposed service we developed a case study, implementing an application in medical area. Analyzing the results we can see that the users found the application easy to use and usefulness for health workers at a hospital.

A Semantic Approach for Learning Situation Detection

A number of ubiquitous systems are considering how to deal with situation-awareness to act in a personalized manner according to users needs. Indeed, most of the research efforts in situation-awareness are generally focused on the implementation of common characteristics, differing basically on the relevant context observed and how this contextual information is managed. Consequently, little attention has been paid to an abstract and general view for situation-awareness. The goal of this work is to provide a shift of the attention focus from the implementation to the modeling phase. Our objectives are (1) to define the conceptual modeling of situation-awareness for adaptive and ubiquitous learning systems, (2) to identify its relevant concepts, relationships, and structural, dynamic and representational elements, (3) to propose a method for situation detection. The domain concepts are explored by an application scenario that allows the understanding of the situations configured in u-learning systems and their dynamic factors. The conceptual model was implemented in the CONIC module, which was evaluated in an e-learning system specifying the application and constructing the improvements necessaries to deploy the system in a real application for tests.

An Architectural Model for Situation Awareness in Ubiquitous Computing

One of the major research challenges of Ubiquitous Computing (UbiComp) is related to the need of the applications being aware of the situational context awareness, and when appropriate, respond to it. This paper presents an architecture for situation awareness, called EXEHDA-SA (Execution Environment for Highly Distributed Applications-Situation Awareness). We consider that the main contribution of this work is the architecture that supports acquisition, processing, and dissemination of contextual information, in a distributed way, independently of the application, in an autonomic perspective and rule-based. To assess the functionality of the EXEHDA-SA, we present a case study implemented in Didactic Laboratory of Seed Analysis (LDAS), at Faculty of Agronomy (FAEM), Federal University of Pelotas (UFPel).

A Model of Autonomous Control of the Adaptation to the Context in UbiComp

The research presented in this paper has as main purpose the conception of a mechanism to control the adaptations the context of component-based applications in Ubiquitous Computing, considering the context produced by monitored information, semantic information and inferences from these informations. The premise is to culminate in a model of adaptation, which can be used both by middleware services, as by applications. For this we propose the use of the concepts and technologies related to Semantic Processing and Autonomous Systems in designing a mechanism for control of dynamic adaptation. The conceived model has compared his contributions to the state of the art, and was evaluated by two case studies, with satisfactory results as to meet the demands of ubiquity.

A Proposal Based on IoT for Social Inclusion of People with Visual Impairment

With the wide variety of available mobile devices, of different types, capabilities and technologies, associated with the profusion of wireless communication networks, enables to offer mobile and ubiquitous applications that can be designed to serve blind persons (PCDVs). In this sense, this article has as its principal contribution the approach, called HELIX, proposed to provide accessibility to the visually impaired through the use of concepts of Internet of Things (IoT) in indoor and outdoor environments. The functional architecture of the HELIX is integrated into the adaptation and context recognition subsystem of middleware EXEHDA, which provides support for the acquisition, storage and processing of context information used by the mobile HELIX applications. The applications prototyped were evaluated by the Technology Acceptance Model, and the results were promising.

EXEHDA-HM: A compositional approach to explore contextual information on hybrid models

Abstract The current proposals of hybrid context modeling bring new challenges, an important one is how applications can access and process data stored on these models. Thinking about that, this paper proposes a solution to deal with this challenge through a compositional approach that explores the context information on hybrid models, called EXEHDA-HM. The proposed approach stands out by the design of a repository that supports three database models and by the compositional processing strategy based on rules. In our proposal, the applications can combine data stored on different bases in a single rule, which could enhance the identification of contextual situations. For the evaluation we designed and implemented some case studies on information security area, exploring the hybrid repository composed of relational, non-relational, and triple storage models. Our results demonstrate that was possible to identify richer situations with the data composition across more than one model and there are situations that can only be found through this composition.

Context awareness in UbiComp: An IoT oriented distributed architecture

The recent advances in the Internet of Things (IoT) area, which has provided an increasing availability of networked sensors and actuators, has given a new perspective to research in the context awareness in UbiComp. In this sense, the main contribution of this paper is the proposition of COIOT, an architecture for IoT designed with the aim of providing, through rules, the proactive management of the EXEHDA Middleware interactions with the physical environment. To evaluate the functionalities of the proposed architecture we implemented a case study in the agricultural area. The achieved results are promising.