916 resultados para continuous-resource model


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Compile-time program analysis techniques can be applied to Web service orchestrations to prove or check various properties. In particular, service orchestrations can be subjected to resource analysis, in which safe approximations of upper and lower resource usage bounds are deduced. A uniform analysis can be simultaneously performed for different generalized resources that can be directiy correlated with cost- and performance-related quality attributes, such as invocations of partners, network traffic, number of activities, iterations, and data accesses. The resulting safe upper and lower bounds do not depend on probabilistic assumptions, and are expressed as functions of size or length of data components from an initiating message, using a finegrained structured data model that corresponds to the XML-style of information structuring. The analysis is performed by transforming a BPEL-like representation of an orchestration into an equivalent program in another programming language for which the appropriate analysis tools already exist.

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El Análisis de Consumo de Recursos o Análisis de Coste trata de aproximar el coste de ejecutar un programa como una función dependiente de sus datos de entrada. A pesar de que existen trabajos previos a esta tesis doctoral que desarrollan potentes marcos para el análisis de coste de programas orientados a objetos, algunos aspectos avanzados, como la eficiencia, la precisión y la fiabilidad de los resultados, todavía deben ser estudiados en profundidad. Esta tesis aborda estos aspectos desde cuatro perspectivas diferentes: (1) Las estructuras de datos compartidas en la memoria del programa son una pesadilla para el análisis estático de programas. Trabajos recientes proponen una serie de condiciones de localidad para poder mantener de forma consistente información sobre los atributos de los objetos almacenados en memoria compartida, reemplazando éstos por variables locales no almacenadas en la memoria compartida. En esta tesis presentamos dos extensiones a estos trabajos: la primera es considerar, no sólo los accesos a los atributos, sino también los accesos a los elementos almacenados en arrays; la segunda se centra en los casos en los que las condiciones de localidad no se cumplen de forma incondicional, para lo cual, proponemos una técnica para encontrar las precondiciones necesarias para garantizar la consistencia de la información acerca de los datos almacenados en memoria. (2) El objetivo del análisis incremental es, dado un programa, los resultados de su análisis y una serie de cambios sobre el programa, obtener los nuevos resultados del análisis de la forma más eficiente posible, evitando reanalizar aquellos fragmentos de código que no se hayan visto afectados por los cambios. Los analizadores actuales todavía leen y analizan el programa completo de forma no incremental. Esta tesis presenta un análisis de coste incremental, que, dado un cambio en el programa, reconstruye la información sobre el coste del programa de todos los métodos afectados por el cambio de forma incremental. Para esto, proponemos (i) un algoritmo multi-dominio y de punto fijo que puede ser utilizado en todos los análisis globales necesarios para inferir el coste, y (ii) una novedosa forma de almacenar las expresiones de coste que nos permite reconstruir de forma incremental únicamente las funciones de coste de aquellos componentes afectados por el cambio. (3) Las garantías de coste obtenidas de forma automática por herramientas de análisis estático no son consideradas totalmente fiables salvo que la implementación de la herramienta o los resultados obtenidos sean verificados formalmente. Llevar a cabo el análisis de estas herramientas es una tarea titánica, ya que se trata de herramientas de gran tamaño y complejidad. En esta tesis nos centramos en el desarrollo de un marco formal para la verificación de las garantías de coste obtenidas por los analizadores en lugar de analizar las herramientas. Hemos implementado esta idea mediante la herramienta COSTA, un analizador de coste para programas Java y KeY, una herramienta de verificación de programas Java. De esta forma, COSTA genera las garantías de coste, mientras que KeY prueba la validez formal de los resultados obtenidos, generando de esta forma garantías de coste verificadas. (4) Hoy en día la concurrencia y los programas distribuidos son clave en el desarrollo de software. Los objetos concurrentes son un modelo de concurrencia asentado para el desarrollo de sistemas concurrentes. En este modelo, los objetos son las unidades de concurrencia y se comunican entre ellos mediante llamadas asíncronas a sus métodos. La distribución de las tareas sugiere que el análisis de coste debe inferir el coste de los diferentes componentes distribuidos por separado. En esta tesis proponemos un análisis de coste sensible a objetos que, utilizando los resultados obtenidos mediante un análisis de apunta-a, mantiene el coste de los diferentes componentes de forma independiente. Abstract Resource Analysis (a.k.a. Cost Analysis) tries to approximate the cost of executing programs as functions on their input data sizes and without actually having to execute the programs. While a powerful resource analysis framework on object-oriented programs existed before this thesis, advanced aspects to improve the efficiency, the accuracy and the reliability of the results of the analysis still need to be further investigated. This thesis tackles this need from the following four different perspectives. (1) Shared mutable data structures are the bane of formal reasoning and static analysis. Analyses which keep track of heap-allocated data are referred to as heap-sensitive. Recent work proposes locality conditions for soundly tracking field accesses by means of ghost non-heap allocated variables. In this thesis we present two extensions to this approach: the first extension is to consider arrays accesses (in addition to object fields), while the second extension focuses on handling cases for which the locality conditions cannot be proven unconditionally by finding aliasing preconditions under which tracking such heap locations is feasible. (2) The aim of incremental analysis is, given a program, its analysis results and a series of changes to the program, to obtain the new analysis results as efficiently as possible and, ideally, without having to (re-)analyze fragments of code that are not affected by the changes. During software development, programs are permanently modified but most analyzers still read and analyze the entire program at once in a non-incremental way. This thesis presents an incremental resource usage analysis which, after a change in the program is made, is able to reconstruct the upper-bounds of all affected methods in an incremental way. To this purpose, we propose (i) a multi-domain incremental fixed-point algorithm which can be used by all global analyses required to infer the cost, and (ii) a novel form of cost summaries that allows us to incrementally reconstruct only those components of cost functions affected by the change. (3) Resource guarantees that are automatically inferred by static analysis tools are generally not considered completely trustworthy, unless the tool implementation or the results are formally verified. Performing full-blown verification of such tools is a daunting task, since they are large and complex. In this thesis we focus on the development of a formal framework for the verification of the resource guarantees obtained by the analyzers, instead of verifying the tools. We have implemented this idea using COSTA, a state-of-the-art cost analyzer for Java programs and KeY, a state-of-the-art verification tool for Java source code. COSTA is able to derive upper-bounds of Java programs while KeY proves the validity of these bounds and provides a certificate. The main contribution of our work is to show that the proposed tools cooperation can be used for automatically producing verified resource guarantees. (4) Distribution and concurrency are today mainstream. Concurrent objects form a well established model for distributed concurrent systems. In this model, objects are the concurrency units that communicate via asynchronous method calls. Distribution suggests that analysis must infer the cost of the diverse distributed components separately. In this thesis we propose a novel object-sensitive cost analysis which, by using the results gathered by a points-to analysis, can keep the cost of the diverse distributed components separate.

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Software testing is a key aspect of software reliability and quality assurance in a context where software development constantly has to overcome mammoth challenges in a continuously changing environment. One of the characteristics of software testing is that it has a large intellectual capital component and can thus benefit from the use of the experience gained from past projects. Software testing can, then, potentially benefit from solutions provided by the knowledge management discipline. There are in fact a number of proposals concerning effective knowledge management related to several software engineering processes. Objective: We defend the use of a lesson learned system for software testing. The reason is that such a system is an effective knowledge management resource enabling testers and managers to take advantage of the experience locked away in the brains of the testers. To do this, the experience has to be gathered, disseminated and reused. Method: After analyzing the proposals for managing software testing experience, significant weaknesses have been detected in the current systems of this type. The architectural model proposed here for lesson learned systems is designed to try to avoid these weaknesses. This model (i) defines the structure of the software testing lessons learned; (ii) sets up procedures for lesson learned management; and (iii) supports the design of software tools to manage the lessons learned. Results: A different approach, based on the management of the lessons learned that software testing engineers gather from everyday experience, with two basic goals: usefulness and applicability. Conclusion: The architectural model proposed here lays the groundwork to overcome the obstacles to sharing and reusing experience gained in the software testing and test management. As such, it provides guidance for developing software testing lesson learned systems.

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Aircraft Operators Companies (AOCs) are always willing to keep the cost of a flight as low as possible. These costs could be modelled using a function of the fuel consumption, time of flight and fixed cost (over flight cost, maintenance, etc.). These are strongly dependant on the atmospheric conditions, the presence of winds and the aircraft performance. For this reason, much research effort is being put in the development of numerical and graphical techniques for defining the optimal trajectory. This paper presents a different approach to accommodate AOCs preferences, adding value to their activities, through the development of a tool, called aircraft trajectory simulator. This tool is able to simulate the actual flight of an aircraft with the constraints imposed. The simulator is based on a point mass model of the aircraft. The aim of this paper is to evaluate 3DoF aircraft model errors with BADA data through real data from Flight Data Recorder FDR. Therefore, to validate the proposed simulation tool a comparative analysis of the state variables vector is made between an actual flight and the same flight using the simulator. Finally, an example of a cruise phase is presented, where a conventional levelled flight is compared with a continuous climb flight. The comparison results show the potential benefits of following user-preferred routes for commercial flights.

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This paper presents the design and results of the implementation of a model for the evaluation and improvement of maintenance management in industrial SMEs. A thorough review of the state of the art on maintenance management was conducted to determine the model variables; to characterize industrial SMEs, a questionnaire was developed with Likert variables collected in the previous step. Once validated the questionnaire, we applied the same to a group of seventy-five (75) SMEs in the industrial sector, located in Bolivar State, Venezuela. To identify the most relevant variables maintenance management, we used exploratory factor analysis technique applied to the data collected. The score obtained for all the companies evaluated (57% compliance), highlights the weakness of maintenance management in industrial SMEs, particularly in the areas of planning and continuous improvement; most SMEs are evaluated in corrective maintenance stage, and its performance standard only response to the occurrence of faults.

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The presented works aim at proposing a methodology for the simulation of offshore wind conditions using CFD. The main objective is the development of a numerical model for the characterization of atmospheric boundary layers of different stability levels, as the most important issue in offshore wind resource assessment. Based on Monin-Obukhov theory, the steady k-ε Standard turbulence model is modified to take into account thermal stratification in the surface layer. The validity of Monin-Obukhov theory in offshore conditions is discussed with an analysis of a three day episode at FINO-1 platform.

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Although numerous modelling efforts have integrated food and water considerations at the farm or river basin level, very few agro-economic models are able to jointly assess water and food policies at the global level. The present report explores the feasibility of integrating water considerations into the CAPRI model. First, a literature review of modelling approaches integrating food and water issues has been conducted. Three agro-economic models, IMPACT, WATERSIM and GLOBIOM, have been analysed in detail. In addition, biophysical and hydrological models estimating agricultural water use have also been studied, in particular the global hydrological model WATERGAP and the LISFLOOD model. Thanks to the programming approach of its supply module, CAPRI shows a high potentiality to integrate environmental indicators as well as to enter new resource constraints (land potentially irrigated, irrigation water) and input-output relationships. At least in theory, the activity-based approach of the regional programming model in CAPRI allows differentiating between rainfed and irrigated activities. The suggested approach to include water into the CAPRI model involves creating an irrigation module and a water use module. The development of the CAPRI water module will enable to provide scientific assessment on agricultural water use within the EU and to analyze agricultural pressures on water resources. The feasibility of the approach has been tested in a pilot case study including two NUTS 2 regions (Andalucia in Spain and Midi-Pyrenees in France). Preliminary results are presented, highlighting the interrelations between water and agricultural developments in Europe. As a next step, it is foreseen to further develop the CAPRI water module to account for competition between agricultural and non-agricultural water use. This will imply building a water use sub-module to compute water use balances.

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This paper deals with the theoretical method and the modelling problems on the analysis of the Pyrotechnic Shock Propagation in the Vehicle Equipment Bay Structure of the ARIANE 5 during the separation of the upper stage. This work has been developed under a contract with the Spanish Firm Construcciones Aeronáuticas S.A. From all the analysis and the studies it can be concluded that: 1.- The mathematical method used for the study of the pyrotechnic shock phenomena is very well suited for conducting parametric studies. 2.- A careful model of the structure should be developed taking into account the realistic stiffness and dissipation properties at the junctions. 3.- The load produced by the pyrotechnic device should be carefully calibrated to reach a good agreement between theoretical and test results. 4.- In any case with the adquired experience it can be said that with the modelling of continuous elements the order of magnitude of the accelerations can be predicted with the accuracy needed in practical applications.

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Antecedentes Europa vive una situación insostenible. Desde el 2008 se han reducido los recursos de los gobiernos a raíz de la crisis económica. El continente Europeo envejece con ritmo constante al punto que se prevé que en 2050 habrá sólo dos trabajadores por jubilado [54]. A esta situación se le añade el aumento de la incidencia de las enfermedades crónicas, relacionadas con el envejecimiento, cuyo coste puede alcanzar el 7% del PIB de un país [51]. Es necesario un cambio de paradigma. Una nueva manera de cuidar de la salud de las personas: sustentable, eficaz y preventiva más que curativa. Algunos estudios abogan por el cuidado personalizado de la salud (pHealth). En este modelo las prácticas médicas son adaptadas e individualizadas al paciente, desde la detección de los factores de riesgo hasta la personalización de los tratamientos basada en la respuesta del individuo [81]. El cuidado personalizado de la salud está asociado a menudo al uso de las tecnologías de la información y comunicación (TICs) que, con su desarrollo exponencial, ofrecen oportunidades interesantes para la mejora de la salud. El cambio de paradigma hacia el pHealth está lentamente ocurriendo, tanto en el ámbito de la investigación como en la industria, pero todavía no de manera significativa. Existen todavía muchas barreras relacionadas a la economía, a la política y la cultura. También existen barreras puramente tecnológicas, como la falta de sistemas de información interoperables [199]. A pesar de que los aspectos de interoperabilidad están evolucionando, todavía hace falta un diseño de referencia especialmente direccionado a la implementación y el despliegue en gran escala de sistemas basados en pHealth. La presente Tesis representa un intento de organizar la disciplina de la aplicación de las TICs al cuidado personalizado de la salud en un modelo de referencia, que permita la creación de plataformas de desarrollo de software para simplificar tareas comunes de desarrollo en este dominio. Preguntas de investigación RQ1 >Es posible definir un modelo, basado en técnicas de ingeniería del software, que represente el dominio del cuidado personalizado de la salud de una forma abstracta y representativa? RQ2 >Es posible construir una plataforma de desarrollo basada en este modelo? RQ3 >Esta plataforma ayuda a los desarrolladores a crear sistemas pHealth complejos e integrados? Métodos Para la descripción del modelo se adoptó el estándar ISO/IEC/IEEE 42010por ser lo suficientemente general y abstracto para el amplio enfoque de esta tesis [25]. El modelo está definido en varias partes: un modelo conceptual, expresado a través de mapas conceptuales que representan las partes interesadas (stakeholders), los artefactos y la información compartida; y escenarios y casos de uso para la descripción de sus funcionalidades. El modelo fue desarrollado de acuerdo a la información obtenida del análisis de la literatura, incluyendo 7 informes industriales y científicos, 9 estándares, 10 artículos en conferencias, 37 artículos en revistas, 25 páginas web y 5 libros. Basándose en el modelo se definieron los requisitos para la creación de la plataforma de desarrollo, enriquecidos por otros requisitos recolectados a través de una encuesta realizada a 11 ingenieros con experiencia en la rama. Para el desarrollo de la plataforma, se adoptó la metodología de integración continua [74] que permitió ejecutar tests automáticos en un servidor y también desplegar aplicaciones en una página web. En cuanto a la metodología utilizada para la validación se adoptó un marco para la formulación de teorías en la ingeniería del software [181]. Esto requiere el desarrollo de modelos y proposiciones que han de ser validados dentro de un ámbito de investigación definido, y que sirvan para guiar al investigador en la búsqueda de la evidencia necesaria para justificarla. La validación del modelo fue desarrollada mediante una encuesta online en tres rondas con un número creciente de invitados. El cuestionario fue enviado a 134 contactos y distribuido en algunos canales públicos como listas de correo y redes sociales. El objetivo era evaluar la legibilidad del modelo, su nivel de cobertura del dominio y su potencial utilidad en el diseño de sistemas derivados. El cuestionario incluía preguntas cuantitativas de tipo Likert y campos para recolección de comentarios. La plataforma de desarrollo fue validada en dos etapas. En la primera etapa se utilizó la plataforma en un experimento a pequeña escala, que consistió en una sesión de entrenamiento de 12 horas en la que 4 desarrolladores tuvieron que desarrollar algunos casos de uso y reunirse en un grupo focal para discutir su uso. La segunda etapa se realizó durante los tests de un proyecto en gran escala llamado HeartCycle [160]. En este proyecto un equipo de diseñadores y programadores desarrollaron tres aplicaciones en el campo de las enfermedades cardio-vasculares. Una de estas aplicaciones fue testeada en un ensayo clínico con pacientes reales. Al analizar el proyecto, el equipo de desarrollo se reunió en un grupo focal para identificar las ventajas y desventajas de la plataforma y su utilidad. Resultados Por lo que concierne el modelo que describe el dominio del pHealth, la parte conceptual incluye una descripción de los roles principales y las preocupaciones de los participantes, un modelo de los artefactos TIC que se usan comúnmente y un modelo para representar los datos típicos que son necesarios formalizar e intercambiar entre sistemas basados en pHealth. El modelo funcional incluye un conjunto de 18 escenarios, repartidos en: punto de vista de la persona asistida, punto de vista del cuidador, punto de vista del desarrollador, punto de vista de los proveedores de tecnologías y punto de vista de las autoridades; y un conjunto de 52 casos de uso repartidos en 6 categorías: actividades de la persona asistida, reacciones del sistema, actividades del cuidador, \engagement" del usuario, actividades del desarrollador y actividades de despliegue. Como resultado del cuestionario de validación del modelo, un total de 65 personas revisó el modelo proporcionando su nivel de acuerdo con las dimensiones evaluadas y un total de 248 comentarios sobre cómo mejorar el modelo. Los conocimientos de los participantes variaban desde la ingeniería del software (70%) hasta las especialidades médicas (15%), con declarado interés en eHealth (24%), mHealth (16%), Ambient Assisted Living (21%), medicina personalizada (5%), sistemas basados en pHealth (15%), informática médica (10%) e ingeniería biomédica (8%) con una media de 7.25_4.99 años de experiencia en estas áreas. Los resultados de la encuesta muestran que los expertos contactados consideran el modelo fácil de leer (media de 1.89_0.79 siendo 1 el valor más favorable y 5 el peor), suficientemente abstracto (1.99_0.88) y formal (2.13_0.77), con una cobertura suficiente del dominio (2.26_0.95), útil para describir el dominio (2.02_0.7) y para generar sistemas más específicos (2_0.75). Los expertos también reportan un interés parcial en utilizar el modelo en su trabajo (2.48_0.91). Gracias a sus comentarios, el modelo fue mejorado y enriquecido con conceptos que faltaban, aunque no se pudo demonstrar su mejora en las dimensiones evaluadas, dada la composición diferente de personas en las tres rondas de evaluación. Desde el modelo, se generó una plataforma de desarrollo llamada \pHealth Patient Platform (pHPP)". La plataforma desarrollada incluye librerías, herramientas de programación y desarrollo, un tutorial y una aplicación de ejemplo. Se definieron cuatro módulos principales de la arquitectura: el Data Collection Engine, que permite abstraer las fuentes de datos como sensores o servicios externos, mapeando los datos a bases de datos u ontologías, y permitiendo interacción basada en eventos; el GUI Engine, que abstrae la interfaz de usuario en un modelo de interacción basado en mensajes; y el Rule Engine, que proporciona a los desarrolladores un medio simple para programar la lógica de la aplicación en forma de reglas \if-then". Después de que la plataforma pHPP fue utilizada durante 5 años en el proyecto HeartCycle, 5 desarrolladores fueron reunidos en un grupo de discusión para analizar y evaluar la plataforma. De estas evaluaciones se concluye que la plataforma fue diseñada para encajar las necesidades de los ingenieros que trabajan en la rama, permitiendo la separación de problemas entre las distintas especialidades, y simplificando algunas tareas de desarrollo como el manejo de datos y la interacción asíncrona. A pesar de ello, se encontraron algunos defectos a causa de la inmadurez de algunas tecnologías empleadas, y la ausencia de algunas herramientas específicas para el dominio como el procesado de datos o algunos protocolos de comunicación relacionados con la salud. Dentro del proyecto HeartCycle la plataforma fue utilizada para el desarrollo de la aplicación \Guided Exercise", un sistema TIC para la rehabilitación de pacientes que han sufrido un infarto del miocardio. El sistema fue testeado en un ensayo clínico randomizado en el cual a 55 pacientes se les dio el sistema para su uso por 21 semanas. De los resultados técnicos del ensayo se puede concluir que, a pesar de algunos errores menores prontamente corregidos durante el estudio, la plataforma es estable y fiable. Conclusiones La investigación llevada a cabo en esta Tesis y los resultados obtenidos proporcionan las respuestas a las tres preguntas de investigación que motivaron este trabajo: RQ1 Se ha desarrollado un modelo para representar el dominio de los sistemas personalizados de salud. La evaluación hecha por los expertos de la rama concluye que el modelo representa el dominio con precisión y con un balance apropiado entre abstracción y detalle. RQ2 Se ha desarrollado, con éxito, una plataforma de desarrollo basada en el modelo. RQ3 Se ha demostrado que la plataforma es capaz de ayudar a los desarrolladores en la creación de software pHealth complejos. Las ventajas de la plataforma han sido demostradas en el ámbito de un proyecto de gran escala, aunque el enfoque genérico adoptado indica que la plataforma podría ofrecer beneficios también en otros contextos. Los resultados de estas evaluaciones ofrecen indicios de que, ambos, el modelo y la plataforma serán buenos candidatos para poderse convertir en una referencia para futuros desarrollos de sistemas pHealth. ABSTRACT Background Europe is living in an unsustainable situation. The economic crisis has been reducing governments' economic resources since 2008 and threatening social and health systems, while the proportion of older people in the European population continues to increase so that it is foreseen that in 2050 there will be only two workers per retiree [54]. To this situation it should be added the rise, strongly related to age, of chronic diseases the burden of which has been estimated to be up to the 7% of a country's gross domestic product [51]. There is a need for a paradigm shift, the need for a new way of caring for people's health, shifting the focus from curing conditions that have arisen to a sustainable and effective approach with the emphasis on prevention. Some advocate the adoption of personalised health care (pHealth), a model where medical practices are tailored to the patient's unique life, from the detection of risk factors to the customization of treatments based on each individual's response [81]. Personalised health is often associated to the use of Information and Communications Technology (ICT), that, with its exponential development, offers interesting opportunities for improving healthcare. The shift towards pHealth is slowly taking place, both in research and in industry, but the change is not significant yet. Many barriers still exist related to economy, politics and culture, while others are purely technological, like the lack of interoperable information systems [199]. Though interoperability aspects are evolving, there is still the need of a reference design, especially tackling implementation and large scale deployment of pHealth systems. This thesis contributes to organizing the subject of ICT systems for personalised health into a reference model that allows for the creation of software development platforms to ease common development issues in the domain. Research questions RQ1 Is it possible to define a model, based on software engineering techniques, for representing the personalised health domain in an abstract and representative way? RQ2 Is it possible to build a development platform based on this model? RQ3 Does the development platform help developers create complex integrated pHealth systems? Methods As method for describing the model, the ISO/IEC/IEEE 42010 framework [25] is adopted for its generality and high level of abstraction. The model is specified in different parts: a conceptual model, which makes use of concept maps, for representing stakeholders, artefacts and shared information, and in scenarios and use cases for the representation of the functionalities of pHealth systems. The model was derived from literature analysis, including 7 industrial and scientific reports, 9 electronic standards, 10 conference proceedings papers, 37 journal papers, 25 websites and 5 books. Based on the reference model, requirements were drawn for building the development platform enriched with a set of requirements gathered in a survey run among 11 experienced engineers. For developing the platform, the continuous integration methodology [74] was adopted which allowed to perform automatic tests on a server and also to deploy packaged releases on a web site. As a validation methodology, a theory building framework for SW engineering was adopted from [181]. The framework, chosen as a guide to find evidence for justifying the research questions, imposed the creation of theories based on models and propositions to be validated within a scope. The validation of the model was conducted as an on-line survey in three validation rounds, encompassing a growing number of participants. The survey was submitted to 134 experts of the field and on some public channels like relevant mailing lists and social networks. Its objective was to assess the model's readability, its level of coverage of the domain and its potential usefulness in the design of actual, derived systems. The questionnaires included quantitative Likert scale questions and free text inputs for comments. The development platform was validated in two scopes. As a small-scale experiment, the platform was used in a 12 hours training session where 4 developers had to perform an exercise consisting in developing a set of typical pHealth use cases At the end of the session, a focus group was held to identify benefits and drawbacks of the platform. The second validation was held as a test-case study in a large scale research project called HeartCycle the aim of which was to develop a closed-loop disease management system for heart failure and coronary heart disease patients [160]. During this project three applications were developed by a team of programmers and designers. One of these applications was tested in a clinical trial with actual patients. At the end of the project, the team was interviewed in a focus group to assess the role the platform had within the project. Results For what regards the model that describes the pHealth domain, its conceptual part includes a description of the main roles and concerns of pHealth stakeholders, a model of the ICT artefacts that are commonly adopted and a model representing the typical data that need to be formalized among pHealth systems. The functional model includes a set of 18 scenarios, divided into assisted person's view, caregiver's view, developer's view, technology and services providers' view and authority's view, and a set of 52 Use Cases grouped in 6 categories: assisted person's activities, system reactions, caregiver's activities, user engagement, developer's activities and deployer's activities. For what concerns the validation of the model, a total of 65 people participated in the online survey providing their level of agreement in all the assessed dimensions and a total of 248 comments on how to improve and complete the model. Participants' background spanned from engineering and software development (70%) to medical specialities (15%), with declared interest in the fields of eHealth (24%), mHealth (16%), Ambient Assisted Living (21%), Personalized Medicine (5%), Personal Health Systems (15%), Medical Informatics (10%) and Biomedical Engineering (8%) with an average of 7.25_4.99 years of experience in these fields. From the analysis of the answers it is possible to observe that the contacted experts considered the model easily readable (average of 1.89_0.79 being 1 the most favourable scoring and 5 the worst), sufficiently abstract (1.99_0.88) and formal (2.13_0.77) for its purpose, with a sufficient coverage of the domain (2.26_0.95), useful for describing the domain (2.02_0.7) and for generating more specific systems (2_0.75) and they reported a partial interest in using the model in their job (2.48_0.91). Thanks to their comments, the model was improved and enriched with concepts that were missing at the beginning, nonetheless it was not possible to prove an improvement among the iterations, due to the diversity of the participants in the three rounds. From the model, a development platform for the pHealth domain was generated called pHealth Patient Platform (pHPP). The platform includes a set of libraries, programming and deployment tools, a tutorial and a sample application. The main four modules of the architecture are: the Data Collection Engine, which allows abstracting sources of information like sensors or external services, mapping data to databases and ontologies, and allowing event-based interaction and filtering, the GUI Engine, which abstracts the user interface in a message-like interaction model, the Workow Engine, which allows programming the application's user interaction ows with graphical workows, and the Rule Engine, which gives developers a simple means for programming the application's logic in the form of \if-then" rules. After the 5 years experience of HeartCycle, partially programmed with pHPP, 5 developers were joined in a focus group to discuss the advantages and drawbacks of the platform. The view that emerged from the training course and the focus group was that the platform is well-suited to the needs of the engineers working in the field, it allowed the separation of concerns among the different specialities and it simplified some common development tasks like data management and asynchronous interaction. Nevertheless, some deficiencies were pointed out in terms of a lack of maturity of some technological choices, and for the absence of some domain-specific tools, e.g. for data processing or for health-related communication protocols. Within HeartCycle, the platform was used to develop part of the Guided Exercise system, a composition of ICT tools for the physical rehabilitation of patients who suffered from myocardial infarction. The system developed using the platform was tested in a randomized controlled clinical trial, in which 55 patients used the system for 21 weeks. The technical results of this trial showed that the system was stable and reliable. Some minor bugs were detected, but these were promptly corrected using the platform. This shows that the platform, as well as facilitating the development task, can be successfully used to produce reliable software. Conclusions The research work carried out in developing this thesis provides responses to the three three research questions that were the motivation for the work. RQ1 A model was developed representing the domain of personalised health systems, and the assessment of experts in the field was that it represents the domain accurately, with an appropriate balance between abstraction and detail. RQ2 A development platform based on the model was successfully developed. RQ3 The platform has been shown to assist developers create complex pHealth software. This was demonstrated within the scope of one large-scale project, but the generic approach adopted provides indications that it would offer benefits more widely. The results of these evaluations provide indications that both the model and the platform are good candidates for being a reference for future pHealth developments.

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In this paper a new method for fault isolation in a class of continuous-time stochastic dynamical systems is proposed. The method is framed in the context of model-based analytical redundancy, consisting in the generation of a residual signal by means of a diagnostic observer, for its posterior analysis. Once a fault has been detected, and assuming some basic a priori knowledge about the set of possible failures in the plant, the isolation task is then formulated as a type of on-line statistical classification problem. The proposed isolation scheme employs in parallel different hypotheses tests on a statistic of the residual signal, one test for each possible fault. This isolation method is characterized by deriving for the unidimensional case, a sufficient isolability condition as well as an upperbound of the probability of missed isolation. Simulation examples illustrate the applicability of the proposed scheme.

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We present an undergraduate course on concurrent programming where formal models are used in different stages of the learning process. The main practical difference with other approaches lies in the fact that the ability to develop correct concurrent software relies on a systematic transformation of formal models of inter-process interaction (so called shared resources), rather than on the specific constructs of some programming language. Using a resource-centric rather than a language-centric approach has some benefits for both teachers and students. Besides the obvious advantage of being independent of the programming language, the models help in the early validation of concurrent software design, provide students and teachers with a lingua franca that greatly simplifies communication at the classroom and during supervision, and help in the automatic generation of tests for the practical assignments. This method has been in use, with slight variations, for some 15 years, surviving changes in the programming language and course length. In this article, we describe the components and structure of the current incarnation of the course?which uses Java as target language?and some tools used to support our method. We provide a detailed description of the different outcomes that the model-driven approach delivers (validation of the initial design, automatic generation of tests, and mechanical generation of code) from a teaching perspective. A critical discussion on the perceived advantages and risks of our approach follows, including some proposals on how these risks can be minimized. We include a statistical analysis to show that our method has a positive impact in the student ability to understand concurrency and to generate correct code.

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Las evidencias del impacto sobre el medio ambiente asociado al funcionamiento de las ciudades hacen que sea urgente proponer medidas que reduzcan este consumo y mejoren la eficiencia del metabolismo urbano. La existencia de límites en la disponibilidad de recursos materiales y energéticos, plantea actualmente un reto importante al ser humano: ¿son posibles otras formas de organización más adecuadas a esta condición de limitación? Para dar respuesta, resulta fundamental conocer cómo interactuarán nuestros sistemas urbanos en un modelo económico de continuo desarrollo, con la población que alojan, y si podrán adaptarse a la capacidad de carga limitada del Planeta, evitando futuras situaciones de colapso anunciadas desde distintos ámbitos científicos. En ese contexto, la tesis formula un método de análisis del alojamiento que, mediante la evaluación a largo plazo, permita proponer medidas de intervención para reducir el consumo de recursos asociado a su funcionamiento. Se parte de un enfoque ecológico para definir el alojamiento como una parte fundamental del sistema urbano, que está compuesto por tres elementos: habitantes, viviendas y recursos naturales; por tanto, para reducir los impactos asociados al alojamiento es necesario tener en cuenta la diferente naturaleza de estos elementos y el carácter dinámico de las relaciones que se producen entre ellos. La Ecología, a través del estudio de los ecosistemas, ha identificado estrategias de supervivencia y adaptación ante los cambios y perturbaciones. La similitud entre los elementos de un ecosistema (población y soporte) y los del alojamiento (habitantes, viviendas y recursos naturales) permite verificar que la aplicación de estas estrategias al alojamiento puede conducir a situaciones más deseables en la relación de los sistemas urbanos con su entorno A partir de esta hipótesis, se propone un método de análisis diacrónico1 o a largo plazo, para conocer la evolución en el tiempo del alojamiento a través de la cuantificación de una serie de indicadores descriptivos de los habitantes, las viviendas y los recursos naturales. La aplicación de este método a un sistema urbano permitiría conocer las características de los elementos del sistema y, para un ámbito temporal de futuro, prever su evolución, identificar escenarios no deseables y proponer medidas de intervención que corrijan anticipadamente estas situaciones y eviten impactos ambientales innecesarios. La validación del método de análisis se realiza mediante la aplicación al caso de Madrid en periodo retrospectivo (de 1940 a 2010) A partir del estudio de la evolución en Madrid de los indicadores seleccionados, se proponen medidas de intervención en el alojamiento basadas en estrategias ecológicas que habrían conducido a una evolución alternativa con un impacto menor sobre el medio ambiente que la situación actual. El método de análisis se aplica con carácter prospectivo definiendo tres escenarios de futuro para Madrid hasta 2100. Para cada uno de ellos se analiza la evolución previsible de los indicadores y se proponen diferentes medidas de intervención que, desde el punto de vista ecológico, conducirían a una situación más adecuada. La tesis concluye en el interés de este método de análisis diacrónico que permite estimar posibilidades en la evolución futura del alojamiento, identificar las necesidades de recursos para responder a las demandas de los habitantes y, desde un enfoque ecológico, definir, cuantificar y evaluar posibles medidas de intervención que reduzcan los impactos ambientales. El método, por tanto, es una herramienta de interés para la toma de decisiones en la intervención en el alojamiento y en la planificación urbana a largo plazo. ABSTRACT Evidence of the impact on the environment associated with the operation of cities make it urgent to propose measures to reduce energy consumption and improve the efficiency of urban metabolism. The limited availability of materials and energy resources currently poses a significant challenge to human beings: are more appropriate forms of organization for this limitation possible? In response, it is essential to know how our urban systems with the population they host will interact in an economic model of continuous development and whether they can adapt to the limited endurance capacity of the planet, thus avoiding future collapse situations which are being announced from different scientific fields. In this context, the thesis puts forward a method of housing analysis that by a long term assessment will enable to propose intervention measures to reduce resource consumption associated with its operation. The thesis is based on an ecological approach to identify housing as a fundamental part of the urban system, which is composed of three elements: inhabitants, homes and natural resources. Therefore, in order to reduce the impacts associated with housing it is necessary to consider the characteristics of these elements and the dynamic nature of the relationships among them. Ecology, through the analysis of ecosystems, has identified strategies for survival and adaptation to changes and disturbances. The similarity between the elements of an ecosystem (population and support) and housing (inhabitants, homes and natural resources) enables to verify that the implementation of these strategies to housing can lead to better situations in the relationship existing between urban systems with their environment. From this hypothesis, a diachronic or long term analysis method is proposed to know the evolution of housing over time through the quantification of a descriptive indicators series of inhabitants, homes and natural resources. The implementation of this method to a urban system would allow better knowledge of the characteristics of these elements and forecast their development, identify undesirable scenarios and propose early intervention measures to correct these situations and avoid unnecessary environmental impacts. The validation of the method of analysis has been proved in the city of Madrid for the years 1940-2010. From the analysis of the evolution of the indicators selected, accommodation intervention measures are proposed based on ecological strategies that would have led to an alternative development having less impact on the environment than that of the current situation. The analysis method is implemented prospectively defining three future scenarios for the city of Madrid until 2100. The likely evolution of the indicators are analyzed for each scenario and various intervention measures that would lead to a better situation from an ecological point of view are proposed. The thesis conclusion states the interest of this diachronic analysis method to estimate potential future developments in the housing field, identify resource requirements to meet the demands of the citizens and, from an ecological approach, define, quantify and assess possible intervention measures to reduce environmental impacts. The method, therefore, is an interesting tool for decision-making process as for the intervention in housing and urban planning in the long term.

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El proceso de cambio de una sociedad industrial a una sociedad del conocimiento, que experimenta el mundo globalizado en el siglo XXI, induce a las empresas y organizaciones a desarrollar ventajas competitivas y sostenibles basadas en sus activos intangibles, entre los cuales destacan los sistemas de gestión en general y los sistemas de gestión de la calidad (SGC) en particular. Las organizaciones dedicadas a la producción de petróleo están influenciadas por dicha tendencia. El petróleo es un recurso natural con reservas limitadas, cuya producción y consumo ha crecido progresivamente, aportando la mayor cuota (35 %) del total de la energía que se consume en el mundo contemporáneo, aporte que se mantendrá hasta el año 2035, según las previsiones más conservadoras. Por tanto, se hace necesario desarrollar modelos de producción innovadores, que contribuyan a la mejora del factor de recobro de los yacimientos y de la vida útil de los mismos, al tiempo que satisfagan los requerimientos de producción y consumo diarios de los exigentes mercados globales. El objeto de esta investigación es el desarrollo de un modelo de gestión de la calidad y su efecto en el desempeño organizacional, a través del efecto mediador de los constructos satisfacción del cliente interno y gestión del conocimiento en la producción de petróleo. Esta investigación de carácter explicativo, no experimental, transeccional y ex-postfacto, se realizó en la región petrolífera del lago de Maracaibo, al occidente de Venezuela, la cual tiene más de 70 años en producción y cuenta con yacimientos maduros. La población objeto de estudio fue de 369 trabajadores petroleros, quienes participaron en las mesas técnicas de la calidad, durante los meses de mayo y julio del año 2012, los cuales en su mayoría están en proceso de formación como analistas, asesores y auditores de los SGC. La técnica de muestreo aplicada fue de tipo aleatorio simple, con una muestra de 252 individuos. A la misma se le aplicó un cuestionario diseñado ad hoc, el cual fue validado por las técnicas de juicio de expertos y prueba piloto. El procedimiento de investigación se realizó a través de una secuencia, que incluyó la elaboración de un modelo teórico, basado en la revisión del estado del arte; un modelo factorial, sobre la base del análisis factorial de los datos de la encuesta; un modelo de regresión lineal, elaborado a través del método de regresión lineal simple y múltiple; un modelo de análisis de sendero, realizado con el software Amos 20 SPSS y finalmente, un modelo informático, realizado con el simulador Vensim PLE v.6.2. Los resultados obtenidos indican que el modelo teórico se transformó en un modelo empírico, en el cual, la variable independiente fue el SGC, la variable mediadora fue la integración de las dimensiones eliminación de la no conformidad, satisfacción del cliente interno y aprendizaje organizacional (ENCSCIAO) y la variable respuesta la integración de las dimensiones desempeño organizacional y aprendizaje organizacional (DOOA). Se verificó el efecto mediador del ENSCIAO sobre la relación SGC-DOOA con una bondad del ajuste, del 42,65%. En el modelo de regresión múltiple se encontró que las variables determinantes son eliminación de la no conformidad (ENC), conocimiento adquirido (CA) y conocimiento espontáneo (CE), lo cual fue corroborado con el modelo de análisis de sendero. El modelo informático se desarrolló empleando datos aproximados de una unidad de producción tipo, generándose cuatro escenarios; siendo el más favorable, aquel en el cual se aplicaba el SGC y variables relacionadas, reduciendo la desviación de la producción, incrementando el factor de recobro y ampliando la vida útil del yacimiento. Se concluye que la aplicación del SGC y constructos relacionados favorece el desempeño y la producción de las unidades de explotación de yacimientos petrolíferos maduros. Los principales aportes de la tesis son la obtención de un modelo de gestión de la producción de petróleo en yacimientos maduros, basado en los SGC. Asimismo, el desarrollo de un concepto de gestión de la calidad asociado a la reducción de la desviación de la producción petrolífera anual, al incremento del factor de recobro y al aumento de la vida útil del yacimiento. Las futuras líneas de investigación están orientadas a la aplicación del modelo en contextos reales y específicos, para medir su impacto y realizar los ajustes pertinentes. ABSTRACT The process of change from an industrial society to a knowledge-based society, which undergoes the globalized world in the twenty-first century, induces companies and organizations to develop a sustainable and competitive advantages based on its intangible assets, among which are noteworthy the management systems in general and particularly the quality management systems (QMS). Organizations engaged in oil production are influenced by said trend. Oil is a natural resource with limited reserves, where production and consumption has grown progressively, providing the largest share (35%) of the total energy consumed in the contemporary world, a contribution that will remain until the year 2035 according to the more conservative trust estimations. Therefore, it becomes necessary to develop innovative production models which contribute with the improvement of reservoirs´ recovery factor and the lifetime thereof, while meeting the production requirements and daily consumption of demanding global markets. The aim of this research is to develop a model of quality management and its effect on organizational performance through the mediator effect of the constructs, internal customer satisfaction and knowledge management in oil production. This research of explanatory nature, not experimental, transactional and expos-facto was carried out in the oil-region of Maracaibo Lake located to the west of Venezuela, which has more than 70 years in continuous production and has mature reservoirs. The population under study was 369 oil workers who participated in the technical quality workshops, during the months of May and July of 2012, the majority of which were in the process of training as analysts, consultants and auditors of the QMS. The sampling technique applied was simple random type. To a sample of 252 individuals of the population it was applied an ad hoc designed questionnaire, which was validated by the techniques of expert judgment and pilot test. The research procedure was performed through a sequence, which included the elaboration of a theoretical model, based on the review of the state of the art; a factorial model with based on factorial analysis of the survey data; a linear regression model, developed through the method of simple and multiple linear regression; a structural equation model, made with software °Amos 20 SPSS° and finally, a computer model, performed with the simulator Vensim PLE v.6.2. The results indicate that the theoretical model was transformed into an empirical model, in which the independent variable was the QMS, the mediator variable was the integration of the dimensions: elimination of non-conformity, internal customer satisfaction and organizational learning (ENCSCIAO) and the response variable the integration of the dimensions, organizational performance and learning organizational (DOOA). ENSCIAO´s mediator effect on the relation QMS-DOOA was verified with a goodness of fit of 42,65%. In the multiple regression model was found to be the determining variables are elimination of nonconformity (ENC), knowledge acquired (CA) and spontaneous knowledge (EC), which was verified with the structural equation model. The computer model was developed based on approximate data of an oil production unit type, creating four (04) scenarios; being the most favorable, that one which it was applied the QMS and related variables, reducing the production deviation, increasing the recovery factor and extending the lifetime of the reservoir. It is concluded that QMS implementation powered with the related constructs, favors performance and production of mature oilfield of exploitation reservoirs units. The main contributions of this thesis are obtaining a management model for oil production in mature oilfields, based on QMS. In addition, development of a concept of quality associated to reduce the annual oil production deviation, increase the recovery factor and increase oilfield lifetime. Future lines of research are oriented to the implementation of this model in real and specific contexts to measure its impact and make the necessary adjustments that might take place.

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El trabajo de fin de grado que se va a definir detalladamente en esta memoria, trata de poner de manifiesto muchos de los conocimientos que he adquirido a lo largo de la carrera, aplicándolos en un proyecto real. Se ha desarrollado una plataforma capaz de albergar ideas, escritas por personas de todo el mundo que buscan compartirlas con los demás, para que estas sean comentadas, valoradas y entre todos poder mejorarlas. Estas ideas pueden ser de cualquier ámbito, por tanto, se da la posibilidad de clasificarlas en las categorías que mejor encajen con la idea. La aplicación ofrece una API RESTful muy descriptiva, en la que se ha identificado y estructurado cada recurso, para que a través de los “verbos http” se puedan gestionar todos los elementos de una forma fácil y sencilla, independientemente del cliente que la utilice. La arquitectura está montada siguiendo el patrón de diseño modelo vista-controlador, utilizando las últimas tecnologías del mercado como Spring, Liferay, SmartGWT y MongoDB (entre muchas otras) con el objetivo de crear una aplicación segura, escalable y modulada, por lo que se ha tenido que integrar todos estos frameworks. Los datos de la aplicación se hacen persistentes en dos tipos de bases de datos, una relacional (MySQL) y otra no relacional (MongoDB), aprovechando al máximo las características que ofrecen cada una de ellas. El cliente propuesto es accesible mediante un navegador web, se basa en el portal de Liferay. Se han desarrollado varios “Portlets o Widgets”, que componen la estructura de contenido que ve el usuario final. A través de ellos se puede acceder al contenido de la aplicación, ideas, comentarios y demás contenidos sociales, de una forma agradable para el usuario, ya que estos “Portlets” se comunican entre sí y hacen peticiones asíncronas a la API RESTful sin necesidad de recargar toda la estructura de la página. Además, los usuarios pueden registrarse en el sistema para aportar más contenidos u obtener roles que les dan permisos para realizar acciones de administración. Se ha seguido una metodología “Scrum” para la realización del proyecto, con el objetivo de dividir el proyecto en tareas pequeñas y desarrollarlas de una forma ágil. Herramientas como “Jenkins” me han ayudado a una integración continua y asegurando mediante la ejecución de los test de prueba, que todos los componentes funcionan. La calidad ha sido un aspecto principal en el proyecto, se han seguido metodologías software y patrones de diseño para garantizar un diseño de calidad, reutilizable, óptimo y modulado. El uso de la herramienta “Sonar” ha ayudado a este cometido. Además, se ha implementado un sistema de pruebas muy completo de todos los componentes de la aplicación. En definitiva, se ha diseñado una aplicación innovadora de código abierto, que establece unas bases muy definidas para que si algún día se pone en producción, sirva a las personas para compartir pensamientos o ideas ayudando a mejorar el mundo en el que vivimos. ---ABSTRACT---The Final Degree Project, described in detail in this report, attempts to cover a lot of the knowledge I have acquired during my studies, applying it to a real project. The objective of the project has been to develop a platform capable of hosting ideas from people all over the world, where users can share their ideas, comment on and rate the ideas of others and together help improving them. Since these ideas can be of any kind, it is possible to classify them into suitable categories. The application offers a very descriptive API RESTful, where each resource has been identified and organized in a way that makes it possible to easily manage all the elements using the HTTP verbs, regardless of the client using it. The architecture has been built following the design pattern model-view-controller, using the latest market technologies such as Spring, Liferay, Smart GWT and MongoDB (among others) with the purpose of creating a safe, scalable and adjustable application. The data of the application are persistent in two different kinds of databases, one relational (MySQL) and the other non-relational (MongoDB), taking advantage of all the different features each one of them provides. The suggested client is accessible through a web browser and it is based in Liferay. Various “Portlets" or "Widgets” make up the final content of the page. Thanks to these Portlets, the user can access the application content (ideas, comments and categories) in a pleasant way as the Portlets communicate with each other making asynchronous requests to the API RESTful without the necessity to refresh the whole page. Furthermore, users can log on to the system to contribute with more contents or to obtain administrator privileges. The Project has been developed following a “Scrum” methodology, with the main objective being that of dividing the Project into smaller tasks making it possible to develop each task in a more agile and ultimately faster way. Tools like “Jenkins” have been used to guarantee a continuous integration and to ensure that all the components work correctly thanks to the execution of test runs. Quality has been one of the main aspects in this project, why design patterns and software methodologies have been used to guarantee a high quality, reusable, modular and optimized design. The “Sonar” technology has helped in the achievement of this goal. Furthermore, a comprehensive proofing system of all the application's components has been implemented. In conclusion, this Project has consisted in developing an innovative, free source application that establishes a clearly defined basis so that, if it someday will be put in production, it will allow people to share thoughts and ideas, and by doing so, help them to improve the World we live in.

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In previous papers, the type-I intermittent phenomenon with continuous reinjection probability density (RPD) has been extensively studied. However, in this paper type-I intermittency considering discontinuous RPD function in one-dimensional maps is analyzed. To carry out the present study the analytic approximation presented by del Río and Elaskar (Int. J. Bifurc. Chaos 20:1185-1191, 2010) and Elaskar et al. (Physica A. 390:2759-2768, 2011) is extended to consider discontinuous RPD functions. The results of this analysis show that the characteristic relation only depends on the position of the lower bound of reinjection (LBR), therefore for the LBR below the tangent point the relation {Mathematical expression}, where {Mathematical expression} is the control parameter, remains robust regardless the form of the RPD, although the average of the laminar phases {Mathematical expression} can change. Finally, the study of discontinuous RPD for type-I intermittency which occurs in a three-wave truncation model for the derivative nonlinear Schrodinger equation is presented. In all tests the theoretical results properly verify the numerical data