Adenauer Yamin

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-RR: Machine Learning and MCDA with Semantic Web in IoT Resources Classification

Currently, a lot of resources are connected to the Internet, many simultaneously requesting and providing services. The adequate selection of resources that best meet the demands of users with a broad range of options has been a relevant and current research challenge. Based on the non-functional parameters of QoS play a significant role in the ranking of these resources according to the services they offer. This paper aims to aggregate machine learning in the pre-classification of EXEHDA middleware resources, to reduce the computational cost generated by MCDA algorithms. We presented the proposed software architecture (EXEHDA-RR), and the obtained results with the integration of machine learning in the classification process are promissing, and indicate to the research continuation.

Generalized Atanassov’s Intuitionistic Fuzzy Index and Conjugate with S-implications

This work extends the study of properties related to the Generalized Atanassov’s Intuitionistic Fuzzy Index, by considering the concept of conjugate fuzzy implications, mainly interested in the class of S-implications.

fGrid: Uncertainty variables modeling for computational grids using fuzzy logic

The necessity of making a system robust to the uncertainties of the different measures taken from the computing infrastructure is one of the Grid Computing research challenges. In particular, taking relevant information to tasks scheduling from a set of heterogeneous sources and dynamic behavior has been the focus of a significant number of studies. Considering this background, this paper aims to approach a module for task scheduling in Grid Computing, using a taken decision system under uncertainty regime. The proposed module uses the fuzzy logic, called fGrid, to treat uncertainties. Simulations were carried out using the SimGrid framework and modeling GridRS architecture. In addition to the presented results, the a standard scale use with linguistic variation makes both the manipulation of the priority list as the scheduling easier, which contributes to maintainability.

ubiMeter: A proposal for remote instrumentation in IoT

Modern instrumentation systems must typically deal with challenges such as remote access, device heterogeneity and automated configuration. IoT infrastructures can be useful in this scenario because the technologies used in IoT environments can also be used to cope with the cited difficulties. In this paper, we present a remote measurement instrument whose design prioritizes integration with an ubiquitous computing middleware, exploring the convergence between instrumentation and IoT. In particular, the instrument, which is called ubiMeter, uses the context awareness features of the EXEHDA middleware. Its capabilities were evaluated in two different case studies, which yielded promising results.

Integrated Infrastructure for Ubiquitous Learning

Mobile learning is a reality. However, ubiquitous learning approaches are not at a full level of maturity, much of these approaches lacking proposals aiming to provide its practical use. This paper presents an architecture for ubiquitous learning, which employs the paradigm of ontology-based data access (OBDA) for solving problems related to data integration and access of data sources in complex structures. OBDA techniques are explored to allow access and mapping of contextual data and their integration into a students context-aware semantic model. The applicability of this proposal is evaluated through a case study with an e-learning environment and a middleware for ubiquitous computing.

Conjugate fuzzy QL-implications obtained by the OWA-operator

Fuzzy logic is a powerful theory to make a decision which is usually irresolute for one thing or another, making it difficult to reach a final agreement. So, fuzzy connectives have been extensively studied in computer science and widely used in practical applications such as decision-making pattern recognition also including medical diagnosis, clustering analysis and image processing [3]. Fuzzy implications and aggregation functions are mainly study in this work in order to obtain new representative members in the class of fuzzy QL-operators by analysing related mathematical properties. Thus, the aggregating fuzzy QL-subimplications are introduced. They are obtained by action of the OWA-operator performed over the family of the product triangular subnorms along with standard fuzzy negation and the probabilistic sum. As the main results, this family of QL-subimplications extend related QL-implications by preserving their corresponding properties. For that, let U be the unitary interval (Uxa0 [0, 1]). Consider the subconorm Si : U2xa0 U , Si(x, y)xa0 1xa0 1i (1xa0 xxa0 yxa0 xy) for ixa0 1, the product t-norm T : U2xa0 U , T (x, y)xa0 xy and the standard fuzzy negation NS : Uxa0 U , NS(x)xa0 1 x. An n-tuple of real numbers belonging to Un can be aggregate to a single real number on U by an aggregation function, which is a non-decreasing operator satisfying the following boundary conditions: A(0, 0, . . . , 0)xa0 0 and A(1, 1, . . . , 1)xa0 1. Let σ : Nnxa0 Nn be a permutation function ordering the elements: xσ(1)xa0 xσ(2)xa0 . . .xa0 xσ(n). Let w1, w2, . . . , wn be non negative weights (wixa0 0) such that their sum equals one ( n i0wixa0 1). For all xxa0 Un, the n-ary aggregation function A : Unxa0 U called OWA-operator is given as: A(x) n i0 wixσ(i). (1) According with [4, 5], a function I : U2xa0 U is a fuzzy subimplication if it satisfies the boundary conditions I(1, 1)xa0 I(0, 1)xa0 I(0, 0)xa0 1 together with the left antitonicity and right isotonicity. When a subimplication also verifies I(1, 0)xa0 0, it is called a fuzzy implication [1]. Additionally, QL-(sub)implication is a fuzzy (sub)implication defined, for all x, yxa0 U by the following expression: IS,N,T (x, y)xa0 S(N(x), T (x, y)), (2) when T (S) is a t-(co)norm and N is a strong fuzzy negation. This work is supported by the Brazilian funding agencies CAPES and FAPERGS (Ed. PqG 06/2010, under the process number 11/1520-1). Proposition 1. Let ρ : Uxa0 U be an automorphism [2]. The function Ji : U2xa0 U and its conjugate fucntion Jρi : U 2xa0 U , given in Eq.(3) and Eq.(4) respectively, are both fuzzy QL-subimplications: Ji(x, y)xa0 Si(NS(x), TP (x, y))xa0 1 1 i (x x2y), (3) Jρi (x, y)xa0 S ρ i (N ρ S(x), T ρ P (x, y))xa0 ρ 1 ( 1 ρ(x) i (1 ρ(x)ρ(y)) ) , x, yxa0 U. (4) Such family of fuzzy QL-subimplications is referred as J . Proposition 2. The QL-subimplication Ji, Jρixa0 J verify the properties: I1 : If S(N(x), x)xa0 1 then I(x, 1)xa0 1, for all xxa0 U ; I2a : If x1xa0 x2 then I(x1, 0)xa0 I(x2, 0), for all x1, x2xa0 U . I2b : If y1xa0 y2 then I(1, y1)xa0 I(1, y2), for all y1, y2xa0 U . In [6], an k-ary function FA : Ukxa0 U is called as (A,F)-operator and given by: FA(x1, . . . , xk)xa0 A(F1(x1, . . . , xk), . . . , Fn(x1, . . . , xk)), x1, . . . , xkxa0 U. (5) Proposition 3. Let TPxa0 {Si(x, y)xa0 1xa0 1i (1xa0 xxa0 yxa0 xy) : ixa0 1} be a family of t-subnorms. The function TOWA : U2xa0 U is a t-subconorm given by Eq.(6) in the following: SOWA(x, y) n i0 wiSσ(i)(x, y),x, yxa0 U. (6) As the main result, we present the subclass of fuzzy QL-subimplication represented by a t-norm TP , the standard negation NS together with a t-subconorm SP , which is obtained by aggregating n fuzzy t-subconorms of the family SP . Theorem 1. For all x, yxa0 U , the function JOWA : U2xa0 U is a QL-subimplication, given by JOWA(x, y)xa0 SOWA(NS(x), TP (x, y)). (7) Proposition 4. The QL-subimplication JOWA verify Ik for kxa0 {1, 2a, 2b}. Concluding, by Prop. 4, the operator JOWA preserves the main properties of QL-subimplications. Further work considers the interrelations between this class of subimplications and their possible conjugate functions. Another interesting issue is related to dual constructions of QL-subimplications.

A multi-tiered model for context-aware systems

Context awareness is considered one of the most important challenges to be tackled in the field of ubiquitous computing (ubicomp). In this perspective, this paper describes a general model for context-aware systems. The model is organized in multiple tiers, each one addressing a specific design characteristic related to the area. The proposition can be applied in the design and assessment of context-aware systems.

Aggregating fuzzy implications based on OWA-operators

This paper presents the fuzzy (S, N)- QL- and D-subimplication classes, which are obtained by OWA operators performed over the families of triangular subnorms and sub-conorms along with fuzzy negations. Since these classes of subim-plications are explicitly represented by such connectives, the corresponding (S, N)- QL- and D-subimplicatios are characterized by the generalized associativity and distributive properties together with extensions of the exchange and neutrality principles. As the main results, these families of subimplications extend related implications by preserving their corresponding properties.