11 resultados para Voluntary maintenance

em Universidad Politécnica de Madrid


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As a summary of past, current, and future trends in software maintenance and reengineering research, we give in this editorial a retrospective look from the past 14 years to now. We provide insight on how software maintenance has evolved and on the most important research topics presented in the series of the European Conference on Software Maintenance and Reengineering.

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Replication of software engineering experiments is crucial for dealing with validity threats to experiments in this area. Even though the empirical software engineering community is aware of the importance of replication, the replication rate is still very low. The RESER'11 Joint Replication Project aims to tackle this problem by simultaneously running a series of several replications of the same experiment. In this article, we report the results of the replication run at the Universidad Politécnica de Madrid. Our results are inconsistent with the original experiment. However, we have identified possible causes for them. We also discuss our experiences (in terms of pros and cons) during the replication.

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Under the 12th International Conference on Building Materials and Components is inserted this communication related to the field of management of those assets that constitute the Spanish Cultural Heritage and maintenance. This work is related to the field of management of those assets that constitute the Spanish Cultural Heritage which share an artistic or historical background. The conservation and maintenance become a social demand necessary for the preservation of public values, requiring the investment of necessary resources. The legal protection involves a number of obligations and rights to ensure the conservation and heritage protection. The duty of maintenance and upkeep exceeds the useful life the property that must endure more for their cultural value for its usability. The establishment of the necessary conditions to prevent deterioration and precise in order to fulfill its social function, seeking to prolong the life of the asset, preserving their physical integrity and its ability to convey the values protected. This obligation implies a substantial financial effort to the holder of the property, either public or private entity, addressing a problem of economic sustainability. Economic exploitation, with the aim of contributing to their well-maintained, is sometimes the best way to get resources. The work will include different lines of research with the following objectives. - Establishment of processes for assessing total costs over the building life cycle (LCC), during the planning stages or maintenance budgets to determine the most advantageous operating system. - Relationship between the value of property and maintenance costs, and establishing a sensitivity analysis.

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Virtual certification partially substitutes by computer simulations the experimental techniques required for rail vehicle certification. In this paper, several works were these techniques were used in the vehicle design and track maintenance processes are presented. Dynamic simulation of multibody systems was used to virtually apply the EN14363 standard to certify the dynamic behaviour of vehicles. The works described are: assessment of a freight bogie design adapted to meter-gauge, assessment of a railway track layout for a subway network, freight bogie design with higher speed and axle load, and processing of the data acquired by a track recording vehicle for track maintenance.

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This paper describes an interactive set of tools used to determine the safety of tunnels and to provide data for the decision making of its mainteinance. Although, no doubt, there are still several drawbacks in the difficult procedures in use it is clear that the way is promising and future improvements both in experimental and analytical methods will increase our understanding of this matter.

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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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Resulta difícil definir una profesión que surge por la necesidad de adaptar los espacios de trabajo a las nuevas tendencias de las organizaciones, a la productividad, a las nuevas tecnologías que continúan modificando y facilitando desde las últimas décadas el modo y forma de trabajar. Mucho más complicado resulta definir una profesión casi invisible. Cuando todo funciona en un edificio, en un inmueble, en un activo. Todo está correcto. He ahí la dificultad de su definición. Lo que no se ve, no se valora. Las reuniones, las visitas, un puesto de trabajo, una sala de trabajo, una zona de descanso. La climatización, la protección contra incendios, la legionela, el suministro eléctrico, una evacuación. La organización, sus necesidades, su filosofía. Los informes, los análisis, las mejoras. Las personas, el espacio, los procesos, la tecnología. En la actualidad, todo se asocia a su coste. A su rentabilidad. En la difícil tarea de realizar el proyecto de un edificio, participan multitud de aspectos que deben estar perfectamente organizados. El arquitecto proyecta y aúna en el proyecto: pasado (experiencia), presente (tendencias) y futuro (perdurabilidad). Y es en ese momento, cuando al considerar el futuro del edificio, su perdurabilidad, hace que su ciclo de vida sea criterio fundamental al proyectar. Que deba considerarse desde el primer esbozo del proyecto. Para que un edificio perdure en el tiempo existen gran número de factores condicionantes. Empezando por su uso apropiado, su nivel de actividad, pasando por las distintas propiedades que pueda tener, y terminando por los responsables de su mantenimiento en su día a día. Esa profesión invisible, es la disciplina conocida como Facility Management. Otra disciplina no tan novedosa –sus inicios fueron a finales del siglo XIX-, y que en la actualidad se empieza a valorar en gran medida es la Responsabilidad Social. Todo lo que de forma voluntaria, una organización realiza por encima de lo estrictamente legal con objeto de contribuir al desarrollo sostenible (económico, social y medio ambiental). Ambas disciplinas destacan por su continuo dinamismo. Reflejando la evolución de distintas inquietudes: • Personas, procesos, espacios, tecnología • Económica, social, medio-ambiental Y que sólo puede gestionarse con una correcta gestión del cambio. Elemento bisagra entre ambas disciplinas. El presente trabajo de investigación se ha basado en el estudio del grado de sensibilización que existe para con la Responsabilidad Social dentro del sector de la Facility Management en España. Para ello, se han estructurado varios ejercicios con objeto de analizar: la comunicación, el marco actual normativo, la opinión del profesional, del facilities manager. Como objetivo, conocer la implicación actual que la Responsabilidad Social ejerce en el ejercicio de la profesión del Facilities Manager. Se hace especial hincapié en la voluntariedad de ambas disciplinas. De ahí que el presente estudio de investigación realice dicho trabajo sobre elementos voluntarios y por tanto sobre el valor añadido que se obtiene al gestionar dichas disciplinas de forma conjunta y voluntaria. Para que una organización pueda desarrollar su actividad principal –su negocio-, el Facilities Manager gestiona el segundo coste que esta organización tiene. Llegando a poder ser el primero si se incluye el coste asociado al personal (nóminas, beneficios, etc.) Entre el (70 – 80)% del coste de un edificio a lo largo de toda su vida útil, se encuentra en su periodo de explotación. En la perdurabilidad. La tecnología facilita la gestión, pero quien gestiona y lleva a cabo esta perdurabilidad son las personas en los distintos niveles de gestión: estratégico, táctico y operacional. En estos momentos de constante competencia, donde la innovación es el uniforme de batalla, el valor añadido del Facilities Manager se construye gestionando el patrimonio inmobiliario con criterios responsables. Su hecho diferenciador: su marca, su reputación. ABSTRACT It comes difficult to define a profession that emerges due to the need of adapting working spaces to new organization’s trends, productivity improvements and new technologies, which have kept changing and making easier the way that we work during the last decades. Defining an invisible profession results much more complicated than that, because everything is fine when everything works in a building, or in an asset, properly. Hence, there is the difficulty of its definition. What it is not seen, it is not worth. Meeting rooms, reception spaces, work spaces, recreational rooms. HVAC, fire protection, power supply, legionnaire’s disease, evacuation. The organization itself, its needs and its philosophy. Reporting, analysis, improvements. People, spaces, process, technology. Today everything is associated to cost and profitability. In the hard task of developing a building project, a lot of issues, that participate, must be perfectly organized. Architects design and gather/put together in the project: the past (experience), the present (trends) and the future (durability). In that moment, considering the future of the building, e. g. its perdurability, Life Cycle turn as the key point of the design. This issue makes LCC a good idea to have into account since the very first draft of the project. A great number of conditioner factors exist in order to the building resist through time. Starting from a suitable use and the level of activity, passing through different characteristics it may have, and ending daily maintenance responsible. That invisible profession, that discipline, is known as Facility Management. Another discipline, not as new as FM –it begun at the end of XIX century- that is becoming more and more valuable is Social Responsibility. It involves everything a company realizes in a voluntary way, above legal regulations contributing sustainable development (financial, social and environmentally). Both disciplines stand out by their continuous dynamism. Reflecting the evolution of different concerning: • People, process, spaces, technology • Financial, social and environmentally It can only be managed from the right change management. This is the linking point between both disciplines. This research work is based on the study of existing level of increasing sensitivity about Social Responsibility within Facility Management’s sector in Spain. In order to do that, several –five- exercises have been studied with the purpose of analyze: communication, law, professional and facility manager’s opinions. The objective is to know the current implication that Social Responsibility has over Facility Management. It is very important the voluntary part of both disciplines, that’s why the present research work is focused over the voluntary elements and about the added value that is obtained managing the before named disciplines as a whole and in voluntary way. In order a company can develop his core business/primary activities, facility managers must operate the second largest company budget/cost centre. Being the first centre cost if we considerer human resources’ costs included (salaries, incentives…) Among 70-80% building costs are produced along its operative life. Durability Technology ease management, but people are who manage and carry out this durability, within different levels: strategic, tactic and operational. In a world of continuing competence, where innovation is the uniform for the battle, facility manager’s added value is provided managing company’s real estate with responsibility criteria. Their distinguishing element: their brand, their reputation.

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Knowledge acquisition and model maintenance are key problems in knowledge engineering to improve the productivity in the development of intelligent systems. Although historically a number of technical solutions have been proposed in this area, the recent experience shows that there is still an important gap between the way end-users describe their expertise and the way intelligent systems represent knowledge. In this paper we propose an original way to cope with this problem based on electronic documents. We propose the concept of intelligent document processor as a tool that allows the end-user to read/write a document explaining how an intelligent system operates in such a way that, if the user changes the content of the document, the intelligent system will react to these changes. The paper presents the structure of such a document based on knowledge categories derived from the modern knowledge modeling methodologies together with a number of requirements to be understandable by end-users and problem solvers.

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This thesis presents a task-oriented approach to telemanipulation for maintenance in large scientific facilities, with specific focus on the particle accelerator facilities at European Organization for Nuclear Research (CERN) in Geneva, Switzerland and GSI Helmholtz Centre for Heavy Ion Research (GSI) in Darmstadt, Germany. It examines how telemanipulation can be used in these facilities and reviews how this differs from the representation of telemanipulation tasks within the literature. It provides methods to assess and compare telemanipulation procedures as well a test suite to compare telemanipulators themselves from a dexterity perspective. It presents a formalisation of telemanipulation procedures into a hierarchical model which can be then used as a basis to aid maintenance engineers in assessing tasks for telemanipulation, and as the basis for future research. The model introduces a new concept of Elemental Actions as the building block of telemanipulation movements and incorporates the dependent factors for procedures at a higher level of abstraction. In order to gain insight into realistic tasks performed by telemanipulation systems within both industrial and research environments a survey of teleoperation experts is presented. Analysis of the responses is performed from which it is concluded that there is a need within the robotics community for physical benchmarking tests which are geared towards evaluating the dexterity of telemanipulators for comparison of their dexterous abilities. A three stage test suite is presented which is designed to allow maintenance engineers to assess different telemanipulators for their dexterity. This incorporates general characteristics of the system, a method to compare kinematic reachability of multiple telemanipulators and physical test setups to assess dexterity from a both a qualitative perspective and measurably by using performance metrics. Finally, experimental results are provided for the application of the proposed test suite onto two telemanipulation systems, one from a research setting and the other within CERN. It describes the procedure performed and discusses comparisons between the two systems, as well as providing input from the expert operator of the CERN system.

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The calibration results of one anemometer equipped with several rotors, varying their size, were analyzed. In each case, the 30-pulses pert turn output signal of the anemometer was studied using Fourier series decomposition and correlated with the anemometer factor (i.e., the anemometer transfer function). Also, a 3-cup analytical model was correlated to the data resulting from the wind tunnel measurements. Results indicate good correlation between the post-processed output signal and the working condition of the cup anemometer. This correlation was also reflected in the results from the proposed analytical model. With the present work the possibility of remotely checking cup anemometer status, indicating the presence of anomalies and, therefore, a decrease on the wind sensor reliability is revealed.

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Con 1.300 millones de personas en el mundo sin acceso a la electricidad (la mayoría en entornos rurales de países empobrecidos), la energía solar fotovoltaica constituye una solución viable técnica y económicamente para electrificar las zonas más remotas del planeta donde las redes eléctricas convencionales no llegan. Casi todos los países en el mundo han desarrollado algún tipo de programa de electrificación fotovoltaica rural durante los últimos 40 años, principalmente los países más pobres, donde a través de diferentes modelos de financiación, se han instalado millones de sistemas solares domiciliarios (pequeños sistemas fotovoltaicos para uso doméstico). Durante este largo período, se han ido superando muchas barreras, como la mejora de la calidad de los sistemas fotovoltaicos, la reducción de costes, la optimización del diseño y del dimensionado de los sistemas, la disponibilidad financiera para implantar programas de electrificación rural, etc. Gracias a esto, la electrificación rural descentralizada ha experimentado recientemente un salto de escala caracterizada por la implantación de grandes programas con miles de sistemas solares domiciliarios e integrando largos períodos de mantenimiento. Muchos de estos grandes programas se están llevando a cabo con limitado éxito, ya que generalmente parten de supuestos e hipótesis poco contrastadas con la realidad, comprometiendo así un retorno económico que permita el desarrollo de esta actividad a largo plazo. En este escenario surge un nuevo reto: el de cómo garantizar la sostenibilidad de los grandes programas de electrificación rural fotovoltaica. Se argumenta que la principal causa de esta falta de rentabilidad es el imprevisto alto coste de la fase de operación y mantenimiento. Cuestiones clave tales como la estructura de costes de operación y mantenimiento o la fiabilidad de los componentes del sistema fotovoltaico no están bien caracterizados hoy en día. Esta situación limita la capacidad de diseñar estructuras de mantenimiento capaces de asegurar la sostenibilidad y la rentabilidad del servicio de operación y mantenimiento en estos programas. Esta tesis doctoral tiene como objetivo responder a estas cuestiones. Se ha realizado varios estudios sobre la base de un gran programa de electrificación rural fotovoltaica real llevado a cabo en Marruecos con más de 13.000 sistemas solares domiciliarios instalados. Sobre la base de este programa se ha hecho una evaluación en profundidad de la fiabilidad de los sistemas solares a partir de los datos de mantenimiento recogidos durante 5 años con más de 80.000 inputs. Los resultados han permitido establecer las funciones de fiabilidad de los equipos tal y como se comportan en condiciones reales de operación, las tasas de fallos y los tiempos medios hasta el fallo para los principales componentes del sistema, siendo este el primer caso de divulgación de resultados de este tipo en el campo de la electrificación rural fotovoltaica. Los dos principales componentes del sistema solar domiciliario, la batería y el módulo fotovoltaico, han sido analizados en campo a través de una muestra de 41 sistemas trabajando en condiciones reales pertenecientes al programa solar marroquí. Por un lado se ha estudiado la degradación de la capacidad de las baterías y por otro la degradación de potencia de los módulos fotovoltaicos. En el caso de las baterías, los resultados nos han permitido caracterizar la curva de degradación en capacidad llegando a obtener una propuesta de nueva definición del umbral de vida útil de las baterías en electrificación rural. También sobre la base del programa solar de Marruecos se ha llevado a cabo un estudio de caracterización de los costes reales de operación y mantenimiento a partir de la base de datos de contabilidad del programa registrados durante 5 años. Los resultados del estudio han permitido definir cuáles son costes que más incidencia tienen en el coste global. Se han obtenido los costes unitarios por sistema instalado y se han calculado los montantes de las cuotas de mantenimiento de los usuarios para garantizar la rentabilidad de la operación y mantenimiento. Finalmente, se propone un modelo de optimización matemática para diseñar estructuras de mantenimiento basado en los resultados de los estudios anteriores. La herramienta, elaborada mediante programación lineal entera mixta, se ha aplicado al programa marroquí con el fin de validar el modelo propuesto. ABSTRACT With 1,300 million people worldwide deprived of access to electricity (mostly in rural environments), photovoltaic solar energy has proven to be a cost‐effective solution and the only hope for electrifying the most remote inhabitants of the planet, where conventional electric grids do not reach because they are unaffordable. Almost all countries in the world have had some kind of rural photovoltaic electrification programme during the past 40 years, mainly the poorer countries, where through different organizational models, millions of solar home systems (small photovoltaic systems for domestic use) have been installed. During this long period, many barriers have been overcome, such as quality enhancement, cost reduction, the optimization of designing and sizing, financial availability, etc. Thanks to this, decentralized rural electrification has recently experienced a change of scale characterized by new programmes with thousands of solar home systems and long maintenance periods. Many of these large programmes are being developed with limited success, as they have generally been based on assumptions that do not correspond to reality, compromising the economic return that allows long term activity. In this scenario a new challenge emerges, which approaches the sustainability of large programmes. It is argued that the main cause of unprofitability is the unexpected high cost of the operation and maintenance of the solar systems. In fact, the lack of a paradigm in decentralized rural services has led to many private companies to carry out decentralized electrification programmes blindly. Issues such as the operation and maintenance cost structure or the reliability of the solar home system components have still not been characterized. This situation does not allow optimized maintenance structure to be designed to assure the sustainability and profitability of the operation and maintenance service. This PhD thesis aims to respond to these needs. Several studies have been carried out based on a real and large photovoltaic rural electrification programme carried out in Morocco with more than 13,000 solar home systems. An in‐depth reliability assessment has been made from a 5‐year maintenance database with more than 80,000 maintenance inputs. The results have allowed us to establish the real reliability functions, the failure rate and the main time to failure of the main components of the system, reporting these findings for the first time in the field of rural electrification. Both in‐field experiments on the capacity degradation of batteries and power degradation of photovoltaic modules have been carried out. During the experiments both samples of batteries and modules were operating under real conditions integrated into the solar home systems of the Moroccan programme. In the case of the batteries, the results have enabled us to obtain a proposal of definition of death of batteries in rural electrification. A cost assessment of the Moroccan experience based on a 5‐year accounting database has been carried out to characterize the cost structure of the programme. The results have allowed the major costs of the photovoltaic electrification to be defined. The overall cost ratio per installed system has been calculated together with the necessary fees that users would have to pay to make the operation and maintenance affordable. Finally, a mathematical optimization model has been proposed to design maintenance structures based on the previous study results. The tool has been applied to the Moroccan programme with the aim of validating the model.