462 research outputs found

    Optimal discrimination between transient and permanent faults

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    An important practical problem in fault diagnosis is discriminating between permanent faults and transient faults. In many computer systems, the majority of errors are due to transient faults. Many heuristic methods have been used for discriminating between transient and permanent faults; however, we have found no previous work stating this decision problem in clear probabilistic terms. We present an optimal procedure for discriminating between transient and permanent faults, based on applying Bayesian inference to the observed events (correct and erroneous results). We describe how the assessed probability that a module is permanently faulty must vary with observed symptoms. We describe and demonstrate our proposed method on a simple application problem, building the appropriate equations and showing numerical examples. The method can be implemented as a run-time diagnosis algorithm at little computational cost; it can also be used to evaluate any heuristic diagnostic procedure by compariso

    Improving Voltage Control in MV Smart Grids

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    Enhancing Sustainability by Improving Plant Salt Tolerance through Macro- and Micro-Algal Biostimulants

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    Algal biomass, extracts, or derivatives have long been considered a valuable material to bring benefits to humans and cultivated plants. In the last decades, it became evident that algal formulations can induce multiple effects on crops (including an increase in biomass, yield, and quality), and that algal extracts contain a series of bioactive compounds and signaling molecules, in addition to mineral and organic nutrients. The need to reduce the non-renewable chemical input in agriculture has recently prompted an increase in the use of algal extracts as a plant biostimulant, also because of their ability to promote plant growth in suboptimal conditions such as saline environments is beneficial. In this article, we discuss some research areas that are critical for the implementation in agriculture of macro- and microalgae extracts as plant biostimulants. Specifically, we provide an overview of current knowledge and achievements about extraction methods, compositions, and action mechanisms of algal extracts, focusing on salt-stress tolerance. We also outline current limitations and possible research avenues. We conclude that the comparison and the integration of knowledge on the molecular and physiological response of plants to salt and to algal extracts should also guide the extraction procedures and application methods. The effects of algal biostimulants have been mainly investigated from an applied perspective, and the exploitation of different scientific disciplines is still much needed for the development of new sustainable strategies to increase crop tolerance to salt stress

    Ataxia with oculomotor apraxia type 2: a clinical, pathologic, and genetic study

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    BACKGROUND: Ataxia with oculomotor apraxia type 2 (AOA2) is characterized by onset between age 10 and 22 years, cerebellar atrophy, peripheral neuropathy, oculomotor apraxia (OMA), and elevated serum alpha-fetoprotein (AFP) levels. Recessive mutations in SETX have been described in AOA2 patients. OBJECTIVE: To describe the clinical features of AOA2 and to identify the SETX mutations in 10 patients from four Italian families. METHODS: The patients underwent clinical examination, routine laboratory tests, nerve conduction studies, sural nerve biopsy, and brain MRI. All were screened for SETX mutations. RESULTS: All the patients had cerebellar features, including limb and truncal ataxia, and slurred speech. OMA was observed in two patients, extrapyramidal symptoms in two, and mental impairment in three. High serum AFP levels, motor and sensory axonal neuropathy, and marked cerebellar atrophy on MRI were detected in all the patients who underwent these examinations. Sural nerve biopsy revealed a severe depletion of large myelinated fibers in one patient, and both large and small myelinated fibers in another. Postmortem findings are also reported in one of the patients. Four different homozygous SETX mutations were found (a large-scale deletion, a missense change, a single-base deletion, and a splice-site mutation). CONCLUSIONS: The clinical phenotype of oculomotor apraxia type 2 is fairly homogeneous, showing only subtle intrafamilial variability. OMA is an inconstant finding. The identification of new mutations expands the array of SETX variants, and the finding of a missense change outside the helicase domain suggests the existence of at least one more functional region in the N-terminus of senataxin

    List of requirements on formalisms and selection of appropriate tools

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    This deliverable reports on the activities for the set-up of the modelling environments for the evaluation activities of WP5. To this objective, it reports on the identified modelling peculiarities of the electric power infrastructure and the information infrastructures and of their interdependencies, recalls the tools that have been considered and concentrates on the tools that are, and will be, used in the project: DrawNET, DEEM and EPSys which have been developed before and during the project by the partners, and M\uf6bius and PRISM, developed respectively at the University of Illinois at Urbana Champaign and at the University of Birmingham (and recently at the University of Oxford)

    La Rete Sismica Mobile del Centro Nazionale Terremoti

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    Il monitoraggio sismico e vulcanico del territorio nazionale rappresenta uno dei principali compiti istituzionali dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV). L’INGV svolge tale importante funzione attraverso la gestione e la manutenzione di reti sismiche di diversa tipologia e a differente scala che consentono di monitorare il territorio nazionale in tempo reale. Tre sale di sorveglianza, una sismica presso la sede centrale di Roma e due vulcaniche presso la Sezione di Catania e l’Osservatorio Vesuviano di Napoli, con personale qualificato in turno H24, consentono di elaborare e comunicare tempestivamente al Dipartimento della Protezione Civile Nazionale (DPC) e alle sue strutture regionali eventuali stati di allarme e il livello dell’emergenza. Il Centro Nazionale Terremoti (CNT) è la sezione dell’INGV preposta al monitoraggio sismico del territorio italiano ed interviene in questo importante servizio attraverso la gestione e la manutenzione della Rete Sismica Nazionale (RSN) in collaborazione con le altre sedi dell’INGV dislocate sul territorio e con gli uffici tecnici locali. Competenza del CNT è anche la rete sismica euro-mediterranea (MedNet): una rete di stazioni sismiche a larga banda dislocate nei Paesi che circondano il Mediterraneo in condivisione con molti istituti geofisici. Negli ultimi anni tali reti sono cresciute sia come numero di stazioni che come tecnologia, consentendo di controllare in maniera estesa lo spettro di frequenze emesse dalla sorgente sismica e la ciclicità delle strutture sismogenetiche. In alcune aree del territorio nazionale l’alta densità di tali reti sismiche rende possibile una soglia di detezione degli eventi molto bassa e localizzazioni di elevata precisione che permettono di associare la micro-sismicità alle strutture sismo-genetiche. Tuttavia questo non è tecnicamente ed economicamente possibile in maniera omogenea su tutto il territorio nazionale. Per tale motivo si fa spesso ricorso all’uso di reti temporanee in esperimenti mirati allo studio di aree a peculiare rischio sismico e vulcanico o, in caso di forti terremoti, per aumentare la densità della rete già presente e migliorare il monitoraggio in real-time in modo tale da analizzare con maggior dettaglio l’evoluzione della sequenza. Unità specializzate nella gestione di reti sismologiche temporanee sono presenti in diverse sedi dell’INGV. Esse lavorano in completa autonomia sul territorio di competenza ma sono in grado di realizzare un buon livello di sinergia là dove esperimenti ed emergenze sismiche richiedano una stretta collaborazione. La struttura più grande, sia come numero di strumenti a disposizione (più di 200 tra digitalizzatori e sensori) che come personale impegnato, è la Rete Sismica Mobile (RSM) del CNT che è organizzata in modo da rendere possibile l’impiego della strumentazione in più esperimenti mantenendo una quota di strumenti riservata per gli interventi di emergenza. In questo rapporto tecnico presentiamo la struttura organizzativa ed operativa della RSM del CNT, la strumentazione in uso presso di essa e le diverse configurazioni possibili per le stazioni sismometriche temporanee con l’obiettivo di fornire un manuale d’uso ai ricercatori, tecnologi e tecnici che si interfacciano con la RSM, sia durante l’attività scientifica ordinaria (esperimenti di sismica passiva e attiva) che straordinaria (emergenze sismiche)

    Methodologies synthesis

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    This deliverable deals with the modelling and analysis of interdependencies between critical infrastructures, focussing attention on two interdependent infrastructures studied in the context of CRUTIAL: the electric power infrastructure and the information infrastructures supporting management, control and maintenance functionality. The main objectives are: 1) investigate the main challenges to be addressed for the analysis and modelling of interdependencies, 2) review the modelling methodologies and tools that can be used to address these challenges and support the evaluation of the impact of interdependencies on the dependability and resilience of the service delivered to the users, and 3) present the preliminary directions investigated so far by the CRUTIAL consortium for describing and modelling interdependencies

    Service-level availability estimation of GPRS

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