Low density polyethylene/silica nanocomposite foams. Relationship between chemical composition, particle dispersion, cellular structure and physical properties

Postprint (author's final draft

Automated Purchase Negotiations in a Dynamic Electronic Marketplace

Nowadays, there is a surge of B2C and B2B e-commerce operated\ud on the Internet. However, many of these systems are often nothing\ud more than electronic product or service catalogues. Against this background,\ud it is argued that new generation systems based on automatic\ud negotiation will emerge. This paper covers a particular kind of automatic\ud negotiation systems, where a number of participants in a mobile\ud dynamic electronic marketplace automatically negotiate the purchase of\ud products or services, by means of multiple automated one-to-one bargainings.\ud In a dynamic e-marketplace, the number of buyers and sellers\ud and their preferences may change over time. By mobile we mean that\ud buyers in a commercial area may initiate simultaneous negotiations with\ud several sellers using portable devices like cell phones, laptops or personal\ud digital assistants, so these negotiations do not require participants to be\ud colocated in space. We will show how an expressive approach to fuzzy\ud constraint based agent purchase negotiations in competitive trading environments,\ud is ideally suited to work on these kind of e-marketplaces. An\ud example of mobile e-marketplace, and a comparison between an expressive\ud and an inexpressive approach will be presented to show the efficiency\ud of the proposed solution

A contextual ontology to provide location-aware services and interfaces in smart environments

Context-aware computing is about gathering user information and their environment such as user location and\ud preferences, service status, and nearby devices. Such context information is used to adjust enviroment settings to suit user\ud needs and preferences. As environments can change rapidly, applications must be aware of it and adapt their behaviour in\ud real time. We describe an application that introduces intelligent agents in smart homes to provide location-aware services\ud and interfaces. This application must keep an eye on some context information to carry out user preferences. Our\ud approach is based on a contextual ontology that is a key component to enable context sharing and representation

A fully-distributed, multiagent approach to negotiation in mobile ad-hoc networks

This paper presents an interaction protocol intended to be used in distributed negotiation problems using software agents,\ud which could be applied to multi-agent systems deployed over Personal Digital Assistants (PDAs) connected via wireless\ud networks. We are especially interested in semi-competitive scenarios, where each agent in the system acts on behalf of a\ud user, trying to maximize its user preferences while pursuing a common agreement. In these conditions, and especially if\ud we are dealing with open and dynamic environments like mobile ad-hoc networks, the goals and attitudes of software\ud agents cannot be guaranteed. Taking this into account we propose a protocol where interaction among agents is done in a\ud fully-distributed manner, so that no user can have negotiation privileges over the others

Infraestructura para servicios e interfaces sensibles a la localicación en hogares inteligentes

Some not widespread environments like sophisticated vehicles, adjust controlled elements,\ud like the seat and the rearview, in order to match the preferences of their users. In this context\ud computer systems are fully capable of providing customized interfaces for users. However, this kind\ud of service customization has not yet reached the home environment. Inside real home environments,\ud we can find new services based on automatizing traditional ones, which make our lives easier and\ud more comfortable. However, this services are provided independently, the degree of personalization is\ud still very low, and the results are insufficient. The smart home must release the user from performing\ud routine and tedious tasks to achieve comfort, security, and effective energy management. To achieve\ud this goal, designed systems must use all posible components at home, providing a high quality service.\ud In this paper we extend our previous work on using multiagent systems to build a smart home\ud environment. We describe its funcionality and introduce a new ontology in order to make easy agent\ud communication and knowledge sharing

Modelo de negociación automática bilateral para entornos abiertos de comercio electrónico

Este artículo presenta un modelo para la negociación automática bilateral y multiparámetrica en entornos abiertos de\ud comercio electrónico. El modelo se describe en el ámbito de un entorno competitivo de agentes software, en el que uno\ud de los agentes del sistema actúa como comprador y otro de los agentes como vendedor. En un sistema abierto, la\ud incertidumbre acerca del comportamiento de otro agente es clave, correspondiéndose con la realidad presente en medios\ud convencionales de negociación o en comercio electrónico e Internet. Aún así, la actitud de un agente en un entorno\ud competitivo frente a otro agente, puede diferir en cuanto al nivel de confianza recíproca existente. De esta manera, el\ud modelo integra diferentes estrategias de interacción que son función de este nivel de confianza. Estas estrategias abarcan\ud desde un posicionamiento púramente competitivo, con criterios estrictos de mínima revelación de información, hasta una\ud estrategia cooperativa, en la que este criterio de privacidad se relaja. El modelo es capaz de encontrar una solución o\ud acuerdo justo si dicha solución existe, de manera que en el proceso de negociación ningún usuario tenga privilegios. Se\ud emplean restricciones difusas con prioridades (PFCSPs) con valoraciones y graduación de privacidad para representar\ud propuestas, ya sean específicas o de espacios de soluciones, y para definir el grado de satisfacción de estas posibles\ud soluciones. Dicho grado de satisfacción es función del cumplimiento de las restricciones impuestas al proceso de\ud negociación, del perfil del usuario, y de mecanismos de argumentación

Vericiguat, nuevo pilar en el tratamiento de la insuficiencia cardiaca con fracción de eyección reducida

Heart failure with reduced ejection fraction (HFrEF) is associated with high morbidity and mortality, conditioned by multiple hospitalizations. Vericiguat has currently beenshown to be effective and safe in patients with a recent decompensation. We present a series of three cases using vericiguat in different clinical scenarios: an elderly patient with dilated cardiomyopathy of ischemic origin, a patient with alcoholic cardiomyopathy and polyvalvular heart disease, and a young patient with idiopathic cardiomyopathy. In the 3 cases vericiguat was effective and safe. This medication has been tested and monitored in other studies and we consider it plays an important role in the therapeutic armamentarium of this population, although it is necessary to accumulate more clinical experience.La insuficiencia cardiaca con fracción de eyección reducida (ICFEr) se asocia con una elevada morbimortalidad, condicionada por múltiples hospitalizaciones. Actualmente vericiguat ha mostrado ser eficaz y seguro en pacientes con una descompensación reciente. Presentamos una serie de tres casos clínicos usando vericiguat en diferentes perfiles clínicos: paciente de edad avanzada con miocardiopatía dilatada de origen isquémico, paciente con miocardiopatía de origen enólico y enfermedad polivalvular y paciente joven con miocardiopatía de origen idiopático. En los 3 casos el vericiguat mostró resultados eficaces y seguros. Este fármaco ha sido monitorizado en otros estudios y creemos que constituye un arma terapéutica importante para pacientes con ICFEr, aunque es necesario acumular mayor experiencia clínica

Graphene Derivatives: Controlled Properties, Nanocomposites, and Energy Harvesting Applications

Graphene is a ground‐breaking two‐dimensional (2D) material that possesses outstanding electrical, optical, thermal, and mechanical properties and that promises a new generation of devices. Despite all these, some applications require graphene‐based materials with different characteristics, such as good solubility in organic solvents and a specific band gap to be dispersible in polymer nanocomposite matrix and applied as active layer, electron transport layer (ETL) or hole transport layer (HTL) in organic photovoltaics. Chemically modified graphene derivatives are studied, searching for better dispersions and even more properties for different applications. Most of the attention has been drawn to dispersions of graphene oxides or highly reduced graphene oxides. Therefore, this allows an opportunity to study the characteristics of materials with intermediate oxidation degrees and its applications

Using RFID to Enhance Security in Off-Site Data Storage

Off-site data storage is one of the most widely used strategies in enterprises of all sizes to improve business continuity. In medium-to-large size enterprises, the off-site data storage processes are usually outsourced to specialized providers. However, outsourcing the storage of critical business information assets raises serious security considerations, some of which are usually either disregarded or incorrectly addressed by service providers. This article reviews these security considerations and presents a radio frequency identification (RFID)-based, off-site, data storage management system specifically designed to address security issues. The system relies on a set of security mechanisms or controls that are arranged in security layers or tiers to balance security requirements with usability and costs. The system has been successfully implemented, deployed and put into production. In addition, an experimental comparison with classical bar-code-based systems is provided, demonstrating the system’s benefits in terms of efficiency and failure prevention

A Region-Based Multi-Issue Negotiation Protocol For Non-Monotonic Utility Spaces

Ministerio de Educación y Cienci