This article presents the U-Deal, a decentralized and multi-agent ubiquitous commerce model, that describes a peer-to-peer context aware system, with a distributed context history (trail) engine and a dynamic profile generator. The aim of the model is to provide an automatic deal opportunity recommendation based on user profile, preferences and activities history in a peer-to-peer [...]
This article presents the results of an experience of SMS (Short Message Service) use to support teaching and learning in face to face undergraduate courses (Computer Sciences and Management) in a Brazilian university. The students' perceptions regarding the use of this technology were assessed via a questionnaire answered by the 143 students that participated of [...]
The digital mediation resources used in Distance Education can hinder the teacher's perception about the student's state of mind. However, the textual expression in natural language is widely encouraged in most Distance Education courses, through the use of Virtual Learning Environments and other digital tools. This fact has motivated research efforts in order to identify [...]
A key characteristic of cloud computing is elasticity, automatically adjusting system resources to an application's workload. Both reactive and horizontal approaches represent traditional means to offer this capability, in which rule‐condition‐action statements and upper and lower thresholds occur to instantiate or consolidate compute nodes and virtual machines. Although elasticity can be beneficial for many HPC [...]
Multi-agent systems (MAS) involve a wide variety of agents that interact with each other to achieve their goals. Usually each agent has a particular internal architecture defining its main structure that gives support to the interaction among the entities of MAS. Many modelling languages have been proposed in recent years to represent the internal architectures [...]
This paper evaluates, compares, and discusses different methods for quality control in geodetic data analysis in the general scenario of correlated observations and multiple outliers. The investigated methods are the data snooping procedure, the statistical tests for multiple outliers, the recently proposed quasi-accurate detection of outliers method for correlated observations, the Danish method for correlated [...]
For a reliable assessment of sustainability in big cities, it is imperative to evaluate urban ecosystem conditions and the environment of the cities undergoing economic growth. Urban green spaces are valuable sources of evapotranspiration, which is generated by trees and vegetation; these spaces mitigate urban heat islands in cities. Land surface temperature (LST) is closely [...]
This article proposes Hefestos, an intelligent system applied to ubiquitous accessibility. This model uses ubiquitous computing concepts to manage accessibility resources for people with disabilities. Among the concepts employed, context awareness, user profiles and trails management can be highlighted. The paper proposes an ontology for accessibility and delineates scenarios of its application in everyday life [...]
Elasticity is one of the key features of cloud computing. It allows applications to dynamically scale computing and storage resources, avoiding over- and under-provisioning. In high performance computing (HPC), initiatives are normally modeled to handle bag-of-tasks or key-value applications through a load balancer and a loosely-coupled set of virtual machine (VM) instances. In the joint-field [...]
The cargo transport represents the largest share of logistics costs in most companies. Consequently, companies are investing in tracking and tracing systems aiming to improve services, reduce costs and ensure the safety in cargo transportation. To play a part in this area, we propose in this article SafeTrack, a model for logistics management based on [...]