David García López

Framework for Decentralizing Legacy Applications

Today many Peer-to-peer (P2P) applications are widely used on the Internet. Especially file sharing is a popular P2P application that has, at least partially, replaced the centralized file sharing infrastructure. However, there are still a number of legacy applications that utilize a centralized infrastructure as opposed to a decentralized approach. In this paper we present a generic framework for decentralizing legacy applications. Even though we focus especially on Voice over IP (VoIP), email, and web applications, we believe that our framework could also be utilized with other legacy applications. A notable feature of our framework is that it does not require any changes to legacy applications.

Profiling F/OSS Adoption Modes: An Interpretive Approach

This article presents the findings of a research aimed at characterizing F/OSS migration initiatives, in total 30 experiences have been considered, 19 of which have been conducted by public administrations and the rest by private firms, operating different industries in eight different countries.

The Adoption of Open Source Systems in Public Administrations

This study presents the results of a research conducted for a group of eighteen Public Administrations migrating their systems to open source standards. Public Administrations perceive improvements in the way they offer services, a reduction of the costs and better secured information systems. The migration to open source standards allows Public Administration to offer alternative channels for their relationship with the citizenship. Due to the lack of theoretical models to face with this particular, the research relies on grounded theory as an inductive approach that allows theory building. Migrating to open source depends to a great extent on contextual and organizational factors, as for example the need to change, the political support and the existence of available technological resources, the organizational climate, the motivation of the human resources, the kind of leadership for the project or the organizational complexity. The change efforts have strategic and organizational impacts that the organization must evaluate beforehand.

Diferentes modelos de regresión para describir la relación vO2-fc y para estimar el vO2 a diferentes intensidades de esfuerzo. (Different models of regression to describe the relation VO2-Fc and to consider the VO2).

Muchos son los estudios que demuestran el potencial de la frecuencia cardiaca (FC) para estimar el coste energetico de una actividad fisica, ya que se relaciona directamente con el consumo de oxigeno (V . O2). La mayoria de estudios describen la relacion V . O2- FC como lineal para un amplio rango de esfuerzo, exceptuando los valores de reposo aunque se han propuesto diferentes funciones matematicas continuas no lineales sin existir todavia un acuerdo en la ecuacion mas apropiada. Tambien existen estudios que apuntan un cambio en la relacion V . O2-FC en funcion de la intensidad del esfuerzo. Nuestro objetivo fue determinar cual es la mejor funcion matematica que describe la relacion entre la FC y el V . O2 y decidir cual es la mejor funcion matematica para estimar el V . O2 a diferentes intensidades de esfuerzo. Participaron 14 sujetos que realizaron una prueba de esfuerzo maxima sobre cicloergometro y una prueba que consistia en pedalear a 5 intensidades de esfuerzo (40, 50, 60, 70 y 80% del V . O2max) durante 3 minutos. Durante ambas pruebas se midio V . O2 y frecuencia cardiaca. El modelo lineal y potencial fueron los modelos matematicos mas exactos para describir la relacion V . O2-FC. El mayor error de estimacion se produjo a bajas intensidades de esfuerzo. En conclusion, la eleccion de un tipo u otro de regresion influye en la exactitud del metodo de monitorizacion de la frecuencia cardiaca. Palabras clave: Consumo de oxigeno, frecuencia cardiaca, gasto energetico. === Abstract Many studies demonstrate the potential of the heart rate (HR) to estimate the energy expenditure of a specific physical activity, since it is directly related to the oxygen uptake (V . O2). Studies describe the O2-HR relationship as linear for a great range of effort, apart from the resting, although there have been proposed different continuous nonlinear mathematical functions. Nevertheless, there is no agreement for the best-suited equation by the moment. There are also studies which report changes in the V . O2-HR relationship according to the intensity of the effort. Our objective was to determine which is the best mathematical function to describe the existing relationship among HR and V . O2, and to state which one is the best mathematical function to estimate the V . O2 at different intensities of effort. Fourteen subjects performed a maximal test on a cycle ergometer, and another test which consisted in pedalling at 5 different intensities of effort (40, 50, 60, 70 and 80 % of the V . O2max) during 3 minutes. V . O2 and HR data were collected during both tests. The linear model and the potential model were the most exact mathematical models to describe V . O2-HR relation. The greater estimate error was found at low effort intensities. In conclusion, selecting the regression model can possibly affect of the monitoring method for the HR. Key words: Oxygen uptake, heart rate, energy expenditure.