6,453 research outputs found
FLARE: A design environment for FLASH-based space applications
Designing a mass-memory device (i.e., a solid-state recorder) is one of the typical issues of mission-critical space system applications. Flash-memories could be used for this goal: a huge number of parameters and trade-offs need to be explored. Flash-memories are nonvolatile, shock-resistant and power-economic, but in turn have different drawback: e.g., their cost is higher than normal hard disk and the number of erasure cycles is bounded. Moreover space environment presents various issues especially because of radiations: different and quite often contrasting dimensions need to be explored during the design of a flash-memory based solid-state recorder. No systematic approach has so far been proposed to consider them all as a whole: as a consequence a novel design environment currently under development is aimed at supporting the design of flash-based mass-memory device for space application
Flash-memories in Space Applications: Trends and Challenges
Nowadays space applications are provided with a processing power absolutely overcoming the one available just a few years ago. Typical mission-critical space system applications include also the issue of solid-state recorder(s). Flash-memories are nonvolatile, shock-resistant and power-economic, but in turn have different drawbacks. A solid-state recorder for space applications should satisfy many different constraints especially because of the issues related to radiations: proper countermeasures are needed, together with EDAC and testing techniques in order to improve the dependability of the whole system. Different and quite often contrasting dimensions need to be explored during the design of a flash-memory based solid- state recorder. In particular, we shall explore the most important flash-memory design dimensions and trade-offs to tackle during the design of flash-based hard disks for space application
Exploring Design Dimensions in Flash-based Mass-memory Devices
Mission-critical space system applications present several issues: a typical one is the design of a mass-memory device (i.e., a solid- state recorder). This goal could be accomplished by using flash- memories: the exploration of a huge number of parameters and trade-offs is needed. On the one hand flash-memories are nonvolatile, shock-resistant and power-economic, but on the other hand their cost is higher than normal hard disk, the number of erasure cycles is bounded and other different drawbacks have to be considered. In addition space environment presents various issues especially because of radiations: the design of a flash- memory based solid-state recorder implies the exploration of different and quite often contrasting dimensions. No systematic approach has so far been proposed to consider them all as a whole: as a consequence the design of flash-based mass-memory device for space applications is intended to be supported by a novel design environment currently under development and refinemen
Design Issues and Challenges of File Systems for Flash Memories
This chapter discusses how to properly address the issues of using NAND flash memories as mass-memory devices from the native file system standpoint. We hope that the ideas and the solutions proposed in this chapter will be a valuable starting point for designers of NAND flash-based mass-memory devices
Assessment of landfill leachate biodegradability and treatability by means of allochthonous and autochthonous biomasses
The biodegradability and treatability of a young (3 years old) municipal landfill leachate was evaluated by means of chemical oxygen demand (COD) fractionation tests, based on respirometric techniques. The tests were performed using two different biomasses: one cultivated from the raw leachate (autochthonous biomass) and the other collected from a conventional municipal wastewater treatment plant after its acclimation to leachate (allochthonous biomass). The long term performances of the two biomasses were also studied. The results demonstrated that the amount of biodegradable COD in the leachate was strictly dependent on the biomass that was used to perform the fractionation tests. Using the autochthonous biomass, the amount of biodegradable organic substrate resulted in approximately 75% of the total COD, whereas it was close to 40% in the case of the allochthonous biomass, indicating the capacity of the autochthonous biomass to degrade a higher amount of organic compounds present in the leachate. The autochthonous biomass was characterized by higher biological activity and heterotrophic active fraction (14% vs 7%), whereas the activity of the allochthonous biomass was significantly affected by inhibitory compounds in the leachate, resulting in a lower respiration rate (SOUR = 13 mg O2 gVSS-1 h-1 vs 37 mg O2 gVSS-1 h-1). The long-term performance of the autochthonous and allochthonous biomasses indicated that the former was more suitable for the treatment of raw landfill leachate, ensuring higher removal performance towards the organic pollutants
CleAir monitoring system for particulate matter. A case in the Napoleonic Museum in Rome
Monitoring the air particulate concentration both outdoors and indoors is becoming a more relevant issue in the past few decades. An innovative, fully automatic, monitoring system called CleAir is presented. Such a system wants to go beyond the traditional technique (gravimetric analysis), allowing for a double monitoring approach: the traditional gravimetric analysis as well as the optical spectroscopic analysis of the scattering on the same filters in steady-state conditions. The experimental data are interpreted in terms of light percolation through highly scattering matter by means of the stretched exponential evolution. CleAir has been applied to investigate the daily distribution of particulate matter within the Napoleonic Museum in Rome as a test case
La riforma del collocamento e i nuovi servizi per l’impiego. Commentario al D.Lgs. 19 dicembre 2002, n. 297 e prospettive di attuazione dell’articolo 1, legge 14 febbraio 2003, n. 30
Il volume contiene i contributi di: M. Biagi, M. Bassi, M. Colucci, L. Corazza, L. Degan, L. Fantini, D. Gilli, R. Giorgetti, R. Leoni, C. Magri, G. Razzoli, C. Riviello, S. Rosato, A. Salvoni, D. Savastano, S. Scagliarini, A. Scialdone, P. Sestito, S. Spattini, P. Spinelli, G. Steurs, L. Struyven, M. Tiraboschi e S. Trapani
La riforma Biagi del mercato del lavoro. Prime interpretazioni e proposte di lettura del d.lgs. 10 settembre 2003, n. 276. Il diritto transitorio e i tempi della riforma
Con il d.lgs. n. 276/2003, attuativo della legge Biagi, si è aperta una fase decisiva per la riforma del mercato del lavoro italiano. Cambia infatti il quadro normativo di regolazione dei rapporti di lavoro, in funzione dell’obiettivo di Lisbona di incrementare in modo consistente i tassi di occupazione regolare e le occasioni di lavoro di buona qualità. Esso cambia con una rapidità straordinaria, che è davvero senza precedenti. Pochi mesi di intenso lavoro e 86 articoli sono stati sufficienti a dare attuazione al complessivo impianto di modernizzazione del nostro diritto del lavoro delineato nella legge Biagi. Tale riforma non intende rappresentare il punto finale del progetto di modernizzazione del diritto del lavoro delineato nel Libro Bianco dell’ottobre 2001 e confermato nel Patto per l’Italia del luglio 2002 ma costituisce il punto di partenza – imprescindibile, ma di per sé non sufficiente – del complesso e delicato processo di ridefinizione e razionalizzazione delle regole che governano il nostro mercato del lavoro. Le parole chiave con cui leggere il provvedimento sono piuttosto occupabilità, adattabilità e pari opportunità. Parole moderne ed europee, che sono state importate nel nostro ordinamento soprattutto grazie al pensiero e all’elaborazione progettuale di Marco Biagi. Parole che si traducono, di volta in volta, nel corpo dello schema di decreto, in un sistema efficiente di servizi per l’impiego, pubblici e privati, autorizzati e accreditati, che, in rete fra loro, grazie alla borsa continua nazionale del lavoro, accompagnano e facilitano l’incontro tra coloro che cercano lavoro e coloro che cercano lavoratori; in forme di flessibilità regolata e contrattata con il sindacato, alternative al lavoro precario e nero, in modo da bilanciare le esigenze delle imprese di poter competere sui mercati internazionali con le irrinunciabili istanze di tutela e valorizzazione della persona del lavoratore; in provvedimenti per la formazione continua e il rilancio dell’apprendistato, come canale di formazione per il mercato e un lavoro di qualità; in misure di politica attiva a favore di quei gruppi di lavoratori che oggi incontrano maggiori difficoltà nell’accedere a un lavoro regolare e di buona qualità o anche a conciliare tempi di vita e tempi di lavoro. Il commentario vuole fornire, attraverso i suoi numerosi contributi, una lettura interdisciplinare della riforma
Direct measurement of DNA-mediated adhesion between lipid bilayers
Multivalent interactions between deformable mesoscopic units are ubiquitous
in biology, where membrane macromolecules mediate the interactions between
neighbouring living cells and between cells and solid substrates. Lately,
analogous artificial materials have been synthesised by functionalising the
outer surface of compliant Brownian units, for example emulsion droplets and
lipid vesicles, with selective linkers, in particular short DNA sequences. This
development extended the range of applicability of DNA as a selective glue,
originally applied to solid nano and colloidal particles. On very deformable
lipid vesicles, the coupling between statistical effects of multivalent
interactions and mechanical deformation of the membranes gives rise to complex
emergent behaviours, as we recently contributed to demonstrate [Parolini et
al., Nature Communications, 2015, 6, 5948]. Several aspects of the complex
phenomenology observed in these systems still lack a quantitative experimental
characterisation and fundamental understanding. Here we focus on the
DNA-mediated multivalent interactions of a single liposome adhering to a flat
supported bilayer. This simplified geometry enables the estimate of the
membrane tension induced by the DNA-mediated adhesive forces acting on the
liposome. Our experimental investigation is completed by morphological
measurements and the characterisation of the DNA-melting transition, probed by
in-situ F\"{o}rster Resonant Energy Transfer spectroscopy. Experimental results
are compared with the predictions of an analytical theory that couples the
deformation of the vesicle to a full description of the statistical mechanics
of mobile linkers. With at most one fitting parameter, our theory is capable of
semi-quantitatively matching experimental data, confirming the quality of the
underlying assumptions.Comment: 16 pages, 7 figure
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