186 research outputs found

    Energy-Aware Topology Control Strategy for Human-Centric Wireless Sensor Networks

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    The adoption of mobile and ubiquitous solutions that involve participatory or opportunistic sensing increases every day. This situation has highlighted the relevance of optimizing the energy consumption of these solutions, because their operation depends on the devices’ battery lifetimes. This article presents a study that intends to understand how the prediction of topology control messages in human-centric wireless sensor networks can be used to help reduce the energy consumption of the participating devices. In order to do that, five research questions have been defined and a study based on simulations was conducted to answer these questions. The obtained results help identify suitable mobile computing scenarios where the prediction of topology control messages can be used to save energy of the network nodes. These results also allow estimating the percentage of energy saving that can be expected, according to the features of the work scenario and the participants behavior. Designers of mobile collaborative applications that involve participatory or opportunistic sensing, can take advantage of these findings to increase the autonomy of their solutions.Fil: Meseguer, Roc . Universidad Politecnica de Catalunya; EspañaFil: Molina, Carlos. Universitat Rovira I Virgili; EspañaFil: Ochoa, Sergio F.. Universidad de Chile; ChileFil: Santos, Rodrigo Martin. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras. Laboratorio de Sistemas Digitales; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico BahĂ­a Blanca. Instituto de InvestigaciĂłn en IngenierĂ­a ElĂ©ctrica; Argentin

    Teaching Software Engineering from a Collaborative Perspective: Some Latin-American Experiences

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    Teaching software engineering has been recognized as an important challenge for computer science undergraduate programs. Instruction in such area requires not only to deliver theoretical knowledge, but also to perform practical experiences that allow students to assimilate and apply such knowledge. This paper presents some results of two Computer-Supported Collaborative Learning (CSCL) experiences that involved students of software engineering courses from four Latin American Universities. The obtained results were satisfactory and indicate the reported collaborative activity could be appropriate to address teaching software engineering.Teaching software engineering has been recognized as an important challenge for computer science undergraduate programs. Instruction in such area requires not only to deliver theoretical knowledge, but also to perform practical experiences that allow students to assimilate and apply such knowledge. This paper presents some results of two Computer-Supported Collaborative Learning (CSCL) experiences that involved students of software engineering courses from four Latin American Universities. The obtained results were satisfactory and indicate the reported collaborative activity could be appropriate to address teaching software engineering

    Analysis and Design of Mobile Collaborative Applications Using Contextual Elements

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    Collaborative mobile applications support users on the move in order to perform a collaborative task. One of the challenges when designing such applications is to consider the context where they will execute. Contextualized applications are easy to adopt by the users; unfortunately the design of contextualized tools is not evident. This paper presents a framework of contextual elements to be considered during the conception, analysis and design phases of a mobile collaborative application. This framework supports developers to identify non-functional requirements and part of the architectural design in order to get contextualized applications. The use of this framework is complementary to any structured software process. A framework use example is also presented as an illustration of its applicability

    An Architecture to Support the Design and Evaluation of Software Platforms for Partially Virtual Communities

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    Several researchers have identified the design of collaborative systems as a particularly challenging task, because it has to consider services that are not easily identifiable by software designers. The systems that support the activities of partially virtual communities (PVC) are not an exception. Typically, designers of PVC supporting systems are able to identify services that have a visual representation on the user interface, but they usually overlook those that run in the system back-end. In an attempt to help designers to consider these two types of services, this article proposes a software architecture that can be used for both, designing new PVC supporting systems and evaluating existing ones. The architecture was used in three case studies as a design guideline during the development of PVC supporting platforms, and also as an instrument to evaluate three commercial systems. Although the obtained results are still preliminary, they indicate that the architecture is able to accomplish both roles

    An Architecture to Support the Design and Evaluation of Software Platforms for Partially Virtual Communities

    Get PDF
    Several researchers have identified the design of collaborative systems as a particularly challenging task, because it has to consider services that are not easily identifiable by software designers. The systems that support the activities of partially virtual communities (PVC) are not an exception. Typically, designers of PVC supporting systems are able to identify services that have a visual representation on the user interface, but they usually overlook those that run in the system back-end. In an attempt to help designers to consider these two types of services, this article proposes a software architecture that can be used for both, designing new PVC supporting systems and evaluating existing ones. The architecture was used in three case studies as a design guideline during the development of PVC supporting platforms, and also as an instrument to evaluate three commercial systems. Although the obtained results are still preliminary, they indicate that the architecture is able to accomplish both roles

    Modeling IoT-Based Solutions Using Human-Centric Wireless Sensor Networks

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    The Internet of Things (IoT) has inspired solutions that are already available for addressing problems in various application scenarios, such as healthcare, security, emergency support and tourism. However, there is no clear approach to modeling these systems and envisioning their capabilities at the design time. Therefore, the process of designing these systems is ad hoc and its real impact is evaluated once the solution is already implemented, which is risky and expensive. This paper proposes a modeling approach that uses  human-centric wireless sensor networks to specify and evaluate models of IoT-based systems at the time of design, avoiding the need to spend time and effort on early implementations of immature designs. It allows designers to focus on the system design, leaving the implementation decisions for a next phase. The article illustrates the usefulness of this proposal through a running example, showing the design of an IoT-based solution to support the first responses during medium-sized or large urban incidents. The case study used in the proposal evaluation is based on a real train crash. The proposed modeling approach can be used to design IoT-based systems for other application scenarios, e.g., to support security operatives or monitor chronic patients in their homes.Fil: Monares, Álvaro . Universidad de Chile; ChileFil: Ochoa, Sergio F.. Universidad de Chile; ChileFil: Santos, Rodrigo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Investigación en Ingeniería Eléctrica; Argentina. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras; ArgentinaFil: Orozco, Javier Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Investigación en Ingeniería Eléctrica; Argentina. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras; ArgentinaFil: Meseguer, Roc . Universidad Politecnica de Catalunya; Españ

    Predicting topology propagation messages in mobile ad hoc networks: The value of history

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    The mobile ad hoc communication in highly dynamic scenarios, like urban evacuations or search-and-rescue processes, plays a key role in coordinating the activities performed by the participants. Particularly, counting on message routing enhances the communication capability among these actors. Given the high dynamism of these networks and their low bandwidth, having mechanisms to predict the network topology offers several potential advantages; e.g., to reduce the number of topology propagation messages delivered through the network, the consumption of resources in the nodes and the amount of redundant retransmissions. Most strategies reported in the literature to perform these predictions are limited to support high mobility, consume a large amount of resources or require training. In order to contribute towards addressing that challenge, this paper presents a history-based predictor (HBP), which is a prediction strategy based on the assumption that some topological changes in these networks have happened before in the past, therefore, the predictor can take advantage of these patterns following a simple and low-cost approach. The article extends a previous proposal of the authors and evaluates its impact in highly mobile scenarios through the implementation of a real predictor for the optimized link state routing (OLSR) protocol. The use of this predictor, named OLSR-HBP, shows a reduction of 40–55% of topology propagation messages compared to the regular OLSR protocol. Moreover, the use of this predictor has a low cost in terms of CPU and memory consumption, and it can also be used with other routing protocols.Fil: MillĂĄn, Pere. Universitat Rovira I Virgili; EspañaFil: Aliagas, Carles. Universitat Rovira I Virgili; EspañaFil: Molina, Carlos. Universitat Rovira I Virgili; EspañaFil: Meseguer, Roc. Universidad PolitĂ©cnica de Catalunya; EspañaFil: Ochoa, Sergio F.. Universidad de Chile; ChileFil: Santos, Rodrigo Martin. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de Ciencias e IngenierĂ­a de la ComputaciĂłn. Universidad Nacional del Sur. Departamento de Ciencias e IngenierĂ­a de la ComputaciĂłn. Instituto de Ciencias e IngenierĂ­a de la ComputaciĂłn; Argentina. Universidad Nacional del Sur. Departamento de IngenierĂ­a ElĂ©ctrica y de Computadoras; Argentin

    A clinically assisted collaborative system architecture for preventing falls in elderly people

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    Falls in older adults are not only frequent but also potentially disabling for them. Detecting and preventing these falls have an important impact in the life of the elderly people. This paper presents the architecture of a pervasive system designed to perform early detection of older adults in risk of falling or fell down. The system notifies the appropriate people or healthcare organizations in case of detecting a fall of the monitored person. This monitoring process produces minimum disruption in the life style of the elderly.Fil: Orozco, Javier Dario. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras. Laboratorio de Sistemas Digitales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Investigación en Ingeniería Eléctrica; ArgentinaFil: Santos, Rodrigo Martin. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras. Laboratorio de Sistemas Digitales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Investigación en Ingeniería Eléctrica; ArgentinaFil: Ochoa, Sergio F. . Universidad de Chile; ChileFil: Ordinez, Leonardo Damian. Universidad Nacional del Sur. Departamento de Ingenieria Electrica y de Computadoras. Laboratorio de Sistemas Digitales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Investigación en Ingeniería Eléctrica; ArgentinaFil: Meseguer, Roc . Universidad Politecnica de Catalunya; EspañaFil: Baloian, Nelson. Universidad de Chile; Chil

    Multicultural aspects in HCI-curricula

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    In the developing of any kind of interactive and information applications, multicultural aspects, usually, have not been considered. Therefore, people need to adapt to the interfaces instead the opposite, interfaces adapting themselves to the user characteristics. Designing products for international users all above the world is a non solved challenge and will be one of the main goals for future marketing strategies. HCI area has experimented a growth that has occurred as a result of the generalization of computer use and of problems which originate from use by people who are not specifically trained in these appliances. Despite this growth, multicultural aspects in many cases are not included in the HCI Curricula. In recent years, diverse symptoms have expounded that the Ibero-American market is growing very fast to incorporate professionals with HCI backgrounds and solid knowledge about User Centred Design methods. Indeed, these kind of professionals are currently required when developing or localizing interactive systems in this particular scenario. In this paper, we describe the experience of starting the first HCI master in Spanish language for the wide Spanish speaking context held in the University of Lleida (Catalonia, Spain), where we have included specific courses including the multicultural aspects. They will orient the students to have in mind cross-cultural factors when developing international interfaces. In many cases, even it implies adapting evaluation techniques such as usability heuristics traditionally used in HCI courses.This paper was partially supported by the Microsoft Research Project Fund, Grant R0308LAC00

    Resistance of cactus pear (Opuntia ficus-indica) against Pseudocercospora opuntiae through ÎČ‑1,3‑glucanase activity and polyphenolic compounds in cladodes

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    Black spot disease, caused by the hemibiotrophic fungus Pseudocercospora opuntiae, is one of the main phytosanitary problems of cactus (Opuntia spp.). Through mass selection, one cultivar of Opuntia ficus-indica (L.) Mill. resistant to colonization by P. opuntiae was identified. The ethanolic extract of resistant cladodes showed higher levels of total condensed tannins, flavonoids and polyphenols than those of the susceptible genotypes, generating 93% inhibition of P. opuntiae conidial germination in vitro. The total protein in the resistant genotype showed 300% higher ÎČ-1,3-glucanase than the susceptible genotype. This increased activity was able to inhibit germination of conidia by 90%, a similar effect to that of the fungicide CaptanÂź (N‑trichloromethylthio-4-cyclohexene 1,2-dicarboximide). It was shown, for the first time, that the combined action of cactus polyphenols and ÎČ-1,3-glucanase contributes significantly to resistance against P. opuntiae. Activity of this enzyme and the phytochemical profile can be used as criteria to predict and detect cactus germplasm with resistance to black spot.Fil: Ochoa, Maria Judith. Universidad Nacional de Santiago del Estero. Facultad de AgronomĂ­a y Agroindustrias; ArgentinaFil: GonzĂĄlez Flores, L. M.. Instituto TecnolĂłgico de Tlajomulco; MĂ©xicoFil: Cruz Rubio, J. M.. Instituto TecnolĂłgico de Tlajomulco; MĂ©xicoFil: Rivera LĂłpez, L. A.. Instituto TecnolĂłgico de Tlajomulco; MĂ©xicoFil: Rodriguez, Sergio A.. Universidad Nacional de Santiago del Estero; ArgentinaFil: Nazareno, MĂłnica Azucena. Universidad Nacional de Santiago del Estero; Argentina. Universidad Nacional de Santiago del Estero. Facultad de AgronomĂ­a y Agroindustrias; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn; ArgentinaFil: GĂłmez Leyva, J. F.. Instituto TecnolĂłgico de Tlajomulco; MĂ©xic
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