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A Framework for Dialogue-Based Web Services
(2014) Durán, José Javier; Fernández, Alberto
In this paper we describe a framework for dialogue-based applications that require using Web technologies, such as REST services. Not all services are executed in one-shot (e.g. pipe process). However, many applications can only be pfm g gwkflw.Wpp pcf ch c c, fferaframeworkthat assists in their life-cycle: programming, deployment, search, invocation, and feedback management. A running example is used to illustrate our proposal and assess how it improves the experience of service developers.
A Java simulator of Rescorla and Wagner¿s prediction error model and configural cue extensions
(Elsevier, 2012) Alonso, Eduardo; Mondragón, Esther; Fernández, Alberto
In this paper we present the ¿R&W Simulator¿ (version 3.0), a Java simulator of Rescorla and Wagner¿s error correction model of classical conditioning (Rescorla & Wagner, 1972). It is able to run whole experimental designs, and compute and display the associative values of elemental and compound stimuli simultaneously, as well as use extra configural cues in generating compound values (Wagner & Rescorla, 1972); it also permits to change the US across phases. The simulator produces both numerical and graphical outputs, and includes a functionality to export the results to a data processor spreadsheet. It is user-friendly, and built with a graphical interface designed to allow associative learning experts to input the data in their own ¿language¿. It is a cross- platform simulator, so it does not require any special equipment, operative system or support program, and does not need installation. The ¿R&W Simulator¿ (version 3.0) is available free.
A Review on Recent Patents in Digital Processing for Cardiac Electric Signals (II): Advanced Systems and Applications
(2009-07-14T11:13:08Z) Barquero Pérez, Óscar; Goya Esteban, R; Alonso Atienza, Felipe; Requena Carrión, Jesús; Everss, E; García Alberola, Arcadi; Rojo-Álvarez, José Luis
Digital signal processing algorithms for cardiac recordings have been paid much attention in recently disclosed patents. In this second part of our review of the state-of-art patents, systems for sudden cardiac death prediction, as well as for apnea analysis, are summarized. Advanced digital signal processing algorithms for cardiac electric signals are specifically reviewed, including independent component decompositions, and nonlinear methods (chaos, fractals, and entropies). Finally, systems aiming to solve the inverse problem in electrocardiography are presented. Concluding remarks on these systems and on the whole review are discussed.
An Automated Screening System for Tuberculosis
(IEEE, 2013-10) Santiago-Mozos, Ricardo; Pérez-Cruz, Fernando; Madden, Michael G.; Artés-Rodríguez, Antonio
Email Print Request Permissions Save to Project Automated screening systems are commonly used to detect some agent in a sample and take a global decision about the subject (e.g. ill/healthy) based on these detections. We propose a Bayesian methodology for taking decisions in (sequential) screening systems that considers the false alarm rate of the detector. Our approach assesses the quality of its decisions and provides lower bounds on the achievable performance of the screening system from the training data. In addition, we develop a complete screening system for sputum smears in tuberculosis diagnosis, and show, using a real-world database, the advantages of the proposed framework when compared to the commonly used count detections and threshold approach.
An autonomic framework for enhancing the quality of data grid services
(Elsevier, 2012-07) Sanchez, Alberto; Mostes, Jesus; S. Perez, Maria; Cortes, Toni
Data grid services have been used to deal with the increasing needs of applications in terms of data volume and throughput. The large scale, heterogeneity and dynamism of grid environments often make management and tuning of these data services very complex. Furthermore, current high-performance I/O approaches are characterized by their high complexity and specific features that usually require specialized administrator skills. Autonomic computing can help manage this complexity. The present paper describes an autonomic subsystem intended to provide self-management features aimed at efficiently reducing the I/O problem in a grid environment, thereby enhancing the quality of service (QoS) of data access and storage services in the grid. Our proposal takes into account that data produced in an I/O system is not usually immediately required. Therefore, performance improvements are related not only to current but also to any future I/O access, as the actual data access usually occurs later on. Nevertheless, the exact time of the next I/O operations is unknown. Thus, our approach proposes a long-term prediction designed to forecast the future workload of grid components. This enables the autonomic subsystem to determine the optimal data placement to improve both current and future I/O operations.
An experimental comparison of Variable Neighborhood Search variants for the minimization of the vertex-cut in layout problems
(Elsevier, 2012) Sánchez-Oro, Jesús; Duarte, Abraham
Variable Neighborhood Search (VNS) is a metaheuristic for solving optimization problems based on a systematic change of neighborhoods. In recent years, a large variety of VNS strategies have been proposed. However, we have only found limited experimental comparisons among different VNS variants. This paper reviews three VNS strategies for finding near-optimal solutions for vertex-cut minimization problems. Specifically, we consider the min-max variant (Vertex Separation Problem) and the min-sum variant (SumCut Minimization Problem). We also present an preliminary computational comparison of the methods on previously reported instances.
An Approach to Effortless Construction of Program Animations
(Elsevier, 2008-01-01) Velázquez-Iturbide, J. Ángel; Pareja-Flores, Cristóbal; Urquiza-Fuentes, Jaime
Program animation systems have not been as widely adopted by computer science educators as we might expect from the firm belief that they can help in enhancing computer science education. One of the most notable obstacles to their adoption is the considerable effort that the production of program animations represents for the instructor. We present here an approach to reduce such a workload based on the automatic generation of visualizations and animations. The user may customize them in a user-friendly way to construct more expressive program animations. These operations are carried out by means of a user-friendly manipulation based on the metaphor of office documents. We have applied this approach to the functional paradigm by extending the WinHIPE programming environment. Finally, we report on the successful results of an evaluation performed to measure its ease of use.
Bridging the gap between service description models in service matchmaking
(IOS Press, 2012) Fernández, Alberto; Cong, Zijie; Baltá, Analay
In service-oriented architectures (SOA) the process of service discovery involves the matchmaking between service advertisements and service requests. Most approaches assume that both service advertisements and service requests are expressed using the same description language as well as domain ontologies. However, in large-scale open environments that assumption does not hold. In this paper we present a method that addresses the semantic mismatches at service description level. In particular, we focus on the alignment of service description models and service matchmaking on the unified request and advertisements. We propose a matchmaking method that encompasses different semantic, syntactic and hybrid service description languages.
CodeCity: On-Screen or in Virtual Reality?
(IEEE, 2021) Moreno-Lumbreras, David; Minelli, Roberto; Villaverde, Andrea; González-Barahona, Jesús M.; Lanza, Michele
Over the past decades, researchers proposed numerous approaches to visualize source code. A prominent one is CODECITY, an interactive 3D software visualization that leverages the “city metaphor” to represent software system as cities: buildings represent classes (or files) and districts represent packages (or folders). Building dimensions represent values of software metrics, such as the number of methods or the lines of code. There are many implementations of CODECITY, the vast majority of them running on-screen. Recently, some implementations visualizing CODECITY in virtual reality (VR) have appeared. While exciting as a technology, VR’s usefulness remains to be proven. The question we pose is: Is VR well suited to visualize CODECITY, compared to the traditional on-screen implementation? We performed an experiment in our interactive web-based application to visualize CODECITY. Users can fetch data from any git repository and visualize its source code. Our application enables users to navigate CODECITY both on-screen and in an immersive VR environment, using consumer-grade VR headsets like Oculus Quest. Our controlled experiment involved 24 participants from academia and industry. Results show that people using the VR version performed the assigned tasks in much less time, while still maintaining a comparable level of correctness. Therefore, our results show that VR is at least equally wellsuited as on-screen for visualizing CODECITY, and likely better.
Creación de un Clúster de Alta Disponibilidad con software libre
(Novática, 2011) Castro Luis, José Francisco; Vidal López, Miguel
Este artículo introduce los conceptos básicos para entender y crear un clúster de Alta Disponibilidad (HA) con dos nodos en modo activo/activo. En la primera parte se propone un "desafío" consistente en evitar un "split-brain". En una segunda parte, se resolverá el desafío propuesto, y se expondrá el despliegue del clúster HA y su gestión básica. Para ello se utiliza Linux-HA, un producto de software libre multiplataforma basado en el concepto RAS (Reliability, Availability, Serviceability).
Descripción, Descubrimiento y Composición de Servicios en Entornos Multiagente Abiertos. Un Enfoque Organizacional
(DYKINSON S.L., 2010) Fernández, Alberto
Dynamic Coordination in Fleet Management Systems: Toward Smart Cyber Fleets
(IEEE Intelligent Systems, 2014) Billhardt, Holger; Fernández, Alberto; Lemus, Lissette; Lujak, Marin; Osman, Nardine; Ossowski, Sascha; Sierra, Carles
Fleet Management Systems are commonly used to coordinate mobility and delivery services in a broad variety of domains. However, their traditional top-down control architecture becomes a bottleneck in open and dynamic environments, where scalability, proactiveness, and autonomy are becoming key factors for their success. In this paper, we first present an abstract event-based architecture for Fleet Management Systems that supports tailoring dynamic control regimes for coordinating fleet vehicles, and illustrate it for the case of medical emergency management. Then, we go one step ahead in the transition towards automatic or driverless fleets, by conceiving Fleet Management Systems in terms of Cyber-Physical Systems, and putting forward the notion of Cyber Fleets. We illustrate the idea in the field of electro mobility, where we expect drivers of smart e-motorbikes (Cyber Vehicles), equipped with an intelligent communication device (Cyber Helmet), to coordinate in a context-aware manner as part of a decentralised Fleet Management System.
Dynamic Coordination of Ambulances for Emergency Medical Assistance Services
(Elsevier, 2014) Billhardt, Holger; Lujak, Marin; Sánchez-Brunete, Vicente; Fernández, Alberto; Ossowski, Sascha
The main objective of emergency medical assistance (EMA) services is to attend patients with sudden dis- eases at any possible location within an area of influence. This usually consists in providing ``in situ¿¿ assistance and, if necessary, the transport of the patient to a medical center. The potential of such systems to reduce mortality is directly related to the travel times of ambulances to emergency patients. An effi- cient coordination of the ambulance fleet of an EMA service is crucial for reducing the average travel times. In this paper we propose mechanisms that dynamically improve the allocation of ambulances to patients as well as the redeployment of available ambulances in the region under consideration. We test these mechanisms in different experiments using historical data from the EMA service of the Auton- omous Region of Madrid in Spain: SUMMA112. The results empirically confirm that our proposal reduces the average response times of EMA services significantly.
Embedded Design Rationale in Software Architecture
(2010-02-04T14:26:55Z) Capilla, Rafael
The increasing interest to consider design decisions and its rationale as an inherent part of the software architecture development process has led to a number of research works that promote the capturing and use of the architecturally significant decisions. Hence, the stakeholders can keep track of the reasons of changes. This paper explores a variety of initiatives from previous works and advocates for an ¿embedded use of design rationale¿ in software architecting activities with tool support.
Enabling Web Service Discovery in Heterogeneous Environments
(Inderscience Publishers, 2013) Cong, Zijie; Fernández, Alberto
In large, open environments, service discovery has to face the challenge of heterogeneity. Service advertisements published by different organizations or individuals may differ in their description models, thus expressiveness levels. Even on the same expressiveness level, organizations may use assorted domain ontologies. In addition, a service discovery tool may not have a global view of all service advertisements in the system. Unfortunately, most contemporary service discovery approaches rely on these key factors. This paper presents a method that addresses the mismatch problem in description models. A neutral model is proposed in this work for aligning different service description models. A matchmaking method that encompasses different semantic, syntactic and hybrid service description languages based on this neutral model is also presented. Implementation and evaluation of the proposed method showed a satisfactory result.
Event-Driven Architecture for Decision Support in Traffic Management Systems
(Elsevier, 2011) Dunkel, Jürgen; Fernández, Alberto; Ortiz, Rubén; Ossowski, Sascha
Decision support systems for traffic management systems have to cope with a high volume of events continuously generated by sensors. Conventional software architectures do not explicitly target the efficient processing of continuous event streams. Recently, event-driven architectures (EDA) have been proposed as a new paradigm for event-based applications. In this paper we propose a reference architecture for event-driven traffic management systems, which enables the analysis and processing of complex event streams in real-time and is therefore well-suited for decision support in sensor-based traffic control systems. We will illustrate our approach in the domain of road traffic management. In particular, we will report on the redesign of an intelligent transportation management system (ITMS) prototype for the high-capacity road network in Bilbao, Spain.
Exploiting Organisational Information for Service Coordination in Multiagent Systems
(International Foundation for Autonomous Agents and Multiagent Systems, 2008) Fernández, Alberto; Sascha Ossowski
Service-Oriented Computing and Agent Technology are nowadays two of the most active research fields in distributed and open systems. However, when trying to bridge the two worlds, it becomes apparent that the interaction-centric approach of multiagent systems may affect the way services are modelled and enacted, and vice versa. We claim that organisational models that underlie multiagent interactions are crucial in order to take advantage of this interrelation. In this paper we present an approach for modelling organisational structures in service-oriented multiagent systems, and show how it affects semantic service descriptions. We also present approaches to service matchmaking as well as to service composition, capable of exploiting organisational information in service descriptions. In both cases, we prove experimentally the validity of our approach.
Feature Fusion Via Dual-Resolution Compressive Measurement Matrix Analysis For Spectral Image Classi cation
(Elsevier, 2020) Marcos Ramirez, Juan; Martínez Torre, José Ignacio; Arguello, Henry
In the compressive spectral imaging (CSI) framework, di erent architectures have been proposed to recover high-resolution spectral images from compressive measurements. Since CSI architectures compactly capture the relevant information of the spectral image, various methods that extract classi cation features from compressive samples have been recently proposed. However, these techniques require a feature extraction procedure that reorders measurements using the information embedded in the coded aperture patterns. In this paper, a method that fuses features directly from dual-resolution compressive measurements is proposed for spectral image classi cation. More precisely, the fusion method is formulated as an inverse problem that estimates high-spatial-resolution and low-dimensional feature bands from compressive measurements. To this end, the decimation matrices that describe the compressive measurements as degraded versions of the fused features are mathematically modeled using the information embedded in the coded aperture patterns. Furthermore, we include both a sparsity-promoting and a total-variation (TV) regularization terms to the fusion problem in order to consider the correlations between neighbor pixels, and therefore, improve the accuracy of pixel-based classi ers. To solve the fusion problem, we describe an algorithm based on the accelerated variant of the alternating direction method of multipliers (accelerated-ADMM). Additionally, a classi cation approach that includes the developed fusion method and a multilayer neural network is introduced. Finally, the proposed approach is evaluated on three remote sensing spectral images and a set of compressive measurements captured in the laboratory. Extensive simulations show that the proposed classi cation approach outperforms other approaches under various performance metrics.
Fine Virtual Manipulation with Hands of Different Sizes
(GMRV Publications, 2021) Sorli, Suzanne; Verschoor, Mickeal; Casas, Dan; Tajadura-Jiménez, Ana; Otaduy, Miguel A.
Natural interaction with virtual objects relies on two major technology components: hand tracking and hand-object physics simulation. There are functional solutions for these two components, but their hand representations may differ in size and skeletal morphology, hence making the connection non-trivial. In this paper, we introduce a pose retargeting strategy to connect the tracked and simulated hand representations, and we have formulated and solved this hand retargeting as an optimization problem. We have also carried out a user study that demonstrates the effectiveness of our approach to enable fine manipulations that are slow and awkward with na¨ıve approaches.
Growing Support Vector Classifiers with controlled complexity
(2009-07-29T14:43:25Z) Parrado Hernández, E.; Mora Jiménez, Inma; Arenas García, J.; Figueiras Vidal, Aníbal R; Navia Vázquez, Angel
Semiparametric Support Vector Machines have shown to present advantages with respect to nonparametric approaches, in the sense that generalization capability is further improved and the size of the machines is always under control. We propose here an incremental procedure for Growing Support Vector Classifiers, which serves to avoid an a priori architecture estimation or the application of a pruning mechanism after SVM training. The proposed growing approach also opens up new possibilities for dealing with multi-kernel machines, automatic selection of hyperparameters, and fast classification methods. The performance of the proposed algorithm and its extensions is evaluated using several benchmark problems.

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Examinando Artículos de Revista por Materia "1203.17 Informática"