969 resultados para Sistemi ortonormali, spazi di Hilbert.


Relevância:

40.00% 40.00%

Publicador:

Resumo:

The assessment of the RAMS (Reliability, Availability, Maintainability and Safety) performances of system generally includes the evaluations of the “Importance” of its components and/or of the basic parameters of the model through the use of the Importance Measures. The analytical equations proposed in this study allow the estimation of the first order Differential Importance Measure on the basis of the Birnbaum measures of components, under the hypothesis of uniform percentage changes of parameters. The aging phenomena are introduced into the model by assuming exponential-linear or Weibull distributions for the failure probabilities. An algorithm based on a combination of MonteCarlo simulation and Cellular Automata is applied in order to evaluate the performance of a networked system, made up of source nodes, user nodes and directed edges subjected to failure and repair. Importance Sampling techniques are used for the estimation of the first and total order Differential Importance Measures through only one simulation of the system “operational life”. All the output variables are computed contemporaneously on the basis of the same sequence of the involved components, event types (failure or repair) and transition times. The failure/repair probabilities are forced to be the same for all components; the transition times are sampled from the unbiased probability distributions or it can be also forced, for instance, by assuring the occurrence of at least a failure within the system operational life. The algorithm allows considering different types of maintenance actions: corrective maintenance that can be performed either immediately upon the component failure or upon finding that the component has failed for hidden failures that are not detected until an inspection; and preventive maintenance, that can be performed upon a fixed interval. It is possible to use a restoration factor to determine the age of the component after a repair or any other maintenance action.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Nanomedicine is a science based on the preparation of nanosystems for biomedical application. The drugs can be entrapped inside the nanocarriers to improve the drug concentration in the diseased issue through a drug delivery approach; polimeric materials as PLGA-b-PEG has been revealed good properties for this purpose. To improve the nanosystem efficiency it is possible to bind a targeting agent on the carrier surface. In this thesis work silver nanoparticles or drugs as Temsirolimus and Alisertib have been entrapped in PLGA-b-PEG carriers. Chlorotoxin has been linked on the carrier surface as a specific targeting agent for brain tumors. Citotoxicity in vitro of the nanosystems on Glioblastoma cells has been studied.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Questa tesi affronta lo sviluppo di sistemi elettronici per il collaudo automatizzato di centraline elettroniche per sistemi automotive. Viene illustrato lo sviluppo di un simulatore per il collaudo basato su ambiente Labview. Inoltre, viene presentata un'analisi di fattibiltà del rilevamento di malfunzionamenti basata sull'elaborazione di immagini termografiche.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Questa Tesi mira a comparare diversi sistemi software di gestione dei metadati utilizzate dalle maggiori federazioni di identità europee e utilizzati dalle Organizzazioni di Formazione e Istruzione per il proprio Identity Management.