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11.
Ben L. Di Vito 《International Journal on Software Tools for Technology Transfer (STTT)》2000,3(1):20-31
We describe an approach and experimental results in the application of mechanized theorem proving to software requirements
analysis. Serving as the test article was the embedded controller for SAFER, a backpack propulsion system used as a rescue
device by NASA astronauts. SAFER requirements were previously formalized using the prototype verification system (PVS) during
a NASA pilot project in formal methods, details of which appear in a NASA guidebook. This paper focuses on the formulation
and proof of properties for the SAFER requirements model. To test the prospects for deductive requirements analysis, we used
the PVS theorem prover to explore the upper limits of proof automation. A set of property classes was identified, with matching
proof schemes later devised. After developing several PVS proof strategies (essentially prover macros), we obtained fully
automatic proofs of 42 model properties. These results demonstrate how customized prover strategies can be used to automate
moderate-complexity theorem proving for state machine models. 相似文献
12.
Martti Heinonen Miltiadis Anagnostou Stephanie Bell Mark Stevens Robert Benyon Reidun Anita Bergerud Jovan Bojkovski Rien Bosma Jan Nielsen Norbert B?se Plunkett Cromwell Aliye Kartal Dogan Seda Aytekin Ali Uytun Vito Fernicola Krzysztof Flakiewicz Bertrand Blanquart Domen Hudoklin Per Jacobson Anders Kentved Isabel Lóio George Mamontov Alexandra Masarykova Helmut Mitter Regina Mnguni Jan Otych Anton Steiner Nagyné Szilágyi Zsófia Davor Zvizdic 《International Journal of Thermophysics》2012,33(8-9):1422-1437
In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field. 相似文献
13.
Maria Cefola Bernardo Pace Lucrezia Sergio Federico Baruzzi Maria Antonia Gatto Antonia Carito Vito Linsalata Nicholas A. Cascarano Donato Di Venere 《International Journal of Food Science & Technology》2014,49(4):1184-1195
Fresh‐cut ‘Big Top’ nectarines were dipped in 2% (w/v) ascorbic acid–1% (w/v) calcium lactate and stored at 4 °C for up to 12 days in 10 kPa O2‐ and 10 kPa CO2‐modified atmosphere packaging (MAP). The used microperforated plastic film allowed O2 and CO2 concentrations to reach steady values from the fifth day in storage onwards. Samples stored in MAP after chemical dipping showed the highest visual quality score, slight browning symptoms, increment in firmness and very low ethanol and acetaldehyde content. The chemical dipping also increased antioxidant capacity, probably due to the effect of ascorbic acid. The results suggested that the control of yeasts was mainly exerted by MAP, whereas only a slight effect was achieved by the chemical dipping. Therefore, MAP plus ascorbic acid/calcium lactate dipping was the best combination to preserve phytochemical content, antioxidant capacity and microbiological safety of fresh‐cut nectarines during storage. 相似文献
14.
15.
Federico Bertasi Keti Vezzù Guinevere A. Giffin Tetiana Nosach Paul Sideris Steve Greenbaum Michele Vittadello Vito Di Noto 《International Journal of Hydrogen Energy》2014
Molecular relaxation and polarization phenomena of twelve single-ion-conducting nanocomposite polymer electrolytes (nCPEs) are studied using Broadband Electrical Spectroscopy (BES). The electrolytes are obtained by combining PEG400 oligomers with increasing amounts of anionic nanofiller comprised of fluorinated-TiO2 associated with Li+ cations (LiFT®), resulting in [PEG400/(LiFT)y] systems with 0 ≤ y ≤ 26.4. This new class of [PEG400/(LiFT)y] electrolytes allows us to achieve a significant single-ion conductivity (1.1·10−5 S cm−1 at 30 °C for nLi/nO = 0.113) without the addition of lithium salts. To the best of our knowledge, this is the highest conductivity value reported for this class of electrolytes. This study, in conjunction with the results reported in Part 1, leads us to hypothesize a conduction mechanism in terms of two types of long-range charge-transfer processes. The first charge-transfer occurs at the interface between the filler nanoparticles and filler-PEG domains, while the second occurs through the PEG400 matrix with the assistance of polymer segmental motion. The measured Li+ transference numbers confirm that the studied materials are single-ion conductors. 相似文献
16.
Assessment of intradialysis calcium mass balance by a single pool variable‐volume calcium kinetic model
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Salvatore di Filippo Fabio Carfagna Vincenzo la Milia Antonio Bellasi Giustina Casagrande Camilla Bianchi Domenico Vito Maria Laura Costantino Giuseppe Rombolà Claudio Minoretti Carlo Schönholzer Giuseppe Pontoriero Francesco Locatelli 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(1):126-135
Introduction: A reliable method of intradialysis calcium mass balance quantification is far from been established. We herein investigated the use of a single‐pool variable‐volume Calcium kinetic model to assess calcium mass balance in chronic and stable dialysis patients. Methods: Thirty‐four patients on thrice‐weekly HD were studied during 240 dialysis sessions. All patients were dialyzed with a nominal total calcium concentration of 1.50 mmol/L. The main assumption of the model is that the calcium distribution volume is equal to the extracellular volume during dialysis. This hypothesis is assumed valid if measured and predicted end dialysis plasma water ionized calcium concentrations are equal. A difference between predicted and measured end‐dialysis ionized plasma water calcium concentration is a deviation on our main hypothesis, meaning that a substantial amount of calcium is exchanged between the extracellular volume and a nonmodeled compartment. Findings: The difference between predicted and measured values was 0.02 mmol/L (range ?0.08:0.16 mmol/L). With a mean ionized dialysate calcium concentration of 1.25 mmol/L, calcium mass balance was on average negative (mean ± SD ?0.84 ± 1.33 mmol, range ?5.42:2.75). Predialysis ionized plasma water concentration and total ultrafiltrate were the most important predictors of calcium mass balance. A significant mobilization of calcium from the extracellular pool to a nonmodeled pool was calculated in a group of patients. Discussion: The proposed single pool variable‐volume Calcium kinetic model is adequate for prediction and quantification of intradialysis calcium mass balance, it can evaluate the eventual calcium transfer outside the extracellular pool in clinical practice. 相似文献
17.
Laura Caponetti Giovanna Castellano M. Teresa Basile Vito Corsini 《Applied Intelligence》2014,41(1):117-127
Due to the imaging devices, real-world images such as biological images may have poor contrast and be corrupted by noise, so that regions in the images present soft edges and their segmentation turns out to be quite difficult. Fuzzy mathematical morphology can be successfully applied to segment biological images having such characteristics of vagueness and imprecision. In this work we introduce an approach based on fuzzy mathematical morphology to segment images of human oocytes in order to extract the oocyte region from the entire image. The approach applies fuzzy morphological operators to detect soft edges in the oocyte images, followed by morphological reconstruction operators to isolate the oocyte region. The main concepts from fuzzy mathematical morphology are briefly introduced and the results of applying fuzzy morphological operators are reported in low-contrast images of human oocytes. 相似文献
18.
Electrical contact resistance between stainless steel bipolar plate and carbon felt in PEFC: A comprehensive study 总被引:1,自引:0,他引:1
Johan André Laurent Antoni Jean-Pierre Petit Eric De Vito Alexandre Montani 《International Journal of Hydrogen Energy》2009
Bipolar plate represents a key component of Proton Exchange Membrane Fuel Cell (PEFC) with several essential functions, among them the electric connection of elementary cells. Usually made of graphite, this component is studied worldwide in order to develop a commercially viable alternative: different ways have been being investigated, and to date, despite corrosion issues, stainless steel (SS) appears as a good candidate material, but its Electrical Contact Resistance (ECR) can reach unacceptable values when exposed to PEFC environment. This paper offers a comprehensive study of the parameters acting on ECR when using uncoated SS in PEFC: roughness, which influences the surface contact area with carbon baking, bulk composition of the alloy, which influences only partly the nature of passive films, and the composition and structure of passive films, strongly modified by surface treatments and ageing conditions. 相似文献
19.
Antonino Rizzuti Rocco Caliandro Vito Gallo Piero Mastrorilli Giuseppe Chita Mario Latronico 《Food chemistry》2013
X-ray powder diffraction was combined, for the first time, with Nuclear Magnetic Resonance spectroscopy and direct infusion mass spectrometry to characterise fresh and brined grape leaves. Covariance analysis of data generated by the three techniques was performed with the aim to correlate information deriving from the solid part with those obtained for soluble metabolites. The results obtained indicate that crystalline components can be correlated to the metabolites contained in the grape leaves, paving the way to the use of X-ray diffraction analysis for food fingerprinting purposes. Moreover it was ascertained that, differently from most of the metabolites present in the fresh vine leaves, linolenic acid (an omega-3-fatty acid) and quercetin-3-O-glucuronide (a polyphenol metabolite) do not undergo sensible degradation during the brining process, which is used as preservative method for the grape leaves. 相似文献
20.