Search results for "FM"
showing 10 items of 626 documents
A Dempster-Shafer Theory-based approach to the Failure Mode, Effects and Criticality Analysis (FMECA) under epistemic uncertainty: application to the…
2017
Abstract Failure Mode and Effects Analysis (FMEA) is a safety and reliability analysis tool widely used for the identification of system/process potential failures, their causes and consequences. When aimed at the failure modes prioritization, FMEA is named Failure Mode, Effects and Criticality Analysis (FMECA). In the latter case, failure modes are commonly prioritized by means of the Risk Priority Number (RPN) that has been widely criticized to have several shortcomings. Firstly, in the presence of multiple experts supplying different and uncertain judgments on risk parameters, RPN is not able to deal with such a kind of information. Therefore, the present paper proposes the Dempster-Shaf…
Usage of Case-based Reasoning in FMEA-driven Software
2014
Abstract Failure Mode and Effect Analysis (FMEA) is among the most widely used safety analysis procedures in the various industries. The procedure is generally perceived as complex and time-consuming, hindering an effective reuse of previous knowledge. In this paper we present an innovative usage of knowledge system into FMEA process using the Case-based reasoning to reduce the time and effort associated with this analysis. Knowledge system is built to serve multi-projects work that nowadays are in place in any manufacturing or services provider, and knowledge must be retained and reused at the company level and not only at project level. Collaboration is assured trough web-based GUI that s…
Design, manufacturing and testing of a fast disconnecting system for the European target assembly concept of IFMIF
2013
The International Fusion Materials Irradiation Facility (IFMIF) will be equipped with a lithium target assembly to produce the required neutron flux for the irradiation of candidate fusion materials up to a damage rate of 100 dpa (cumulated damage in five years). The present European target assembly design is based on the so called replaceable backplate bayonet concept that was developed with the objective to simplify the maintenance operations for its refurbishment/replacement and to reduce the material for disposal as well. To this purpose it was also conceived to be attached to the lithium pipes and to the beam line by means of remotely operated connections based on clamped flanges with …
A combined multi-criteria approach to support FMECA analyses: A real-world case
2018
[EN] The paper proposes an approach that combines reliability analyses and multi-criteria decision methods to optimize maintenance activities of complex systems. A failure mode, effects, and criticality analysts (FMECA) is initially performed and the fuzzy TOPSIS (FTOPSIS) method is then applied to rank previously identified failure modes. For prioritization, failure modes are assessed against three evaluation criteria that differ from those traditionally involved in risk priority number (RPN) computation (i.e. severity, occurrence and detection). Two criteria refer to the maintenance management reflecting the operational time taken by the maintenance activity performed after the occurrence…
CFD simulations of dense solid–liquid suspensions in baffled stirred tanks: Prediction of solid particle distribution
2013
Abstract Industrial tanks devoted to the mixing of solid particles into liquids are often operated at an impeller speed N less than Njs (defined as the lowest speed allowing the suspension of all particles): under such conditions the distribution of solid-particles is very far from being homogeneous and very significant concentration gradients exist. The present work is devoted to assessing the capability of Computational Fluid Dynamics (CFD) in predicting the particle distribution throughout the tank. The CFD model proposed by Tamburini et al. [58] and successfully applied to the prediction of the sediment amount and shape was adopted here to simulate the particle distribution under partia…
Engineering design and steady state thermomechanical analysis of the IFMIF European lithium target system
2013
In the framework of the current IFMIF Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) phase, ENEA is responsible for the design of the European concept of the IFMIF lithium target system which foresees the possibility to periodically replace only the most irradiated and thus critical component (i.e., the backplate) while continuing to operate the rest of the target for a longer period (bayonet backplate concept). In this work, the results of the steady state thermomechanical analysis of the IFMIF EU target assembly are briefly reported highlighting the relevant indications obtained with respect to the fulfillment of the design requirements. © 2013 IEEE.
"Itsellä ei ole halua ryhtyä miksikään pikkupoliisiksi" : tutkimus lähisuhdeväkivallan puheeksi ottamisesta
2016
Tutkimuksen tavoitteena on pyrkiä ymmärtämään lähisuhdeväkivaltaan liittyviä haasteita ammattilaisten näkökulmasta. Tutkimukseni kohdistuu siihen, minkälaisia esteitä lähisuhdeväkivaltaa työssään kohdanneet ammattilaiset kertovat liittyvän lähisuhdeväkivalta-aiheen puheeksi ottamiseen. Tutkimuksessani selvitin puheeksi ottamisen vaikeutta ja etsin ammattilaisten tapoja selittää tätä. Valitsemaani aihetta perustelen sillä, että tätä näkökulmaa ei ole mielestäni riittävästi aiemmin tutkittu. Tutkimus on aihepiiriltään ajankohtainen ja yhteiskunnallisesti merkittävä, sillä Euroopan unionin perusoikeusviraston (European Union Agency for Fundamental Rights, FRA) raportissa vuodelta 2014 todetaan…
Introducción de nuevos equipos e implementación de técnicas especiales aplicadas al tratamiento de lesiones de piel en radioterapia
2017
En el presente trabajo se ha realizado un análisis de riesgo de dos modalidades de tratamiento radioterápico de piel, la braquiterapia electrónica (eBT) y la irradiación total de la piel con electrones (TSEI). Paralelamente, se ha hecho un estudio de blindajes para la unidad de tratamiento de eBT. El trabajo se ha dividido en 4 capítulos. El capítulo 1 resume las principales ventajas de las técnicas de tratamiento del cáncer de piel no melanoma que se utilizan actualmente en radioterapia, contextualizando la implantación de la eBT. También se expone el tratamiento de la micosis fungoide en radioterapia, enfermedad que afecta a toda la superficie corporal del paciente, para la cual, la TSEI …
The Neural Bases of Event Monitoring across Domains: a Simultaneous ERP-fMRI Study.
2017
The ability to check and evaluate the environment over time with the aim to detect the occurrence of target stimuli is supported by sustained/tonic as well as transient/phasic control processes, which overall might be referred to as event monitoring. The neural underpinning of sustained attentional control processes involves a fronto-parietal network. However, it has not been well-defined yet whether this cortical circuit acts irrespective of the specific material to be monitored and whether this mediates sustained as well as transient monitoring processes. In the current study, the functional activity of brain during an event monitoring task was investigated and compared between two cognit…
Personalidad y Autoestima: Un análisis sobre el importante papel de sus relaciones
2018
The five factor model has been established as one of the main approaches in the study of personality. After its emergence, one of the most important aspects to be analyzed has been its relationship with self-esteem, considering the central role that the latest has in the model. In spite of the large empirical support existing about this relationship, the need of a deeper understanding of its theoretical nature has been pointed out. The aim of our work joins the previous research, in analyzing the existence of relationships between personality factors and self-esteem. The sample was 576 university students, between 18- 35 years old. The present findings show that self-esteem is negatively as…