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41.
This paper investigates the compositional properties of reusable software components defined with explicit dependencies and behavioural contracts expressing rely-guarantee specifications in the form of communication traces. In this setting, connection of components through their matching ports is indeed compositional and yields a new component or composite that respects its constituents’ contracts. Thus the behaviour of the composite is computed from the behaviours of its constituents and is known to conform to the contracts without any new proof. 相似文献
42.
Girard P. Landrault C. Pravossoudovitch S. Virazel A. Wunderlich H.-J. 《Design & Test of Computers, IEEE》2002,19(5):44-52
A new technique, random single-input change (RSIC) test generation, generates low-power test patterns that provide a high level of defect coverage during low-power BIST of digital circuits. The authors propose a parallel BIST implementation of the RSIC generator and analyze its area-overhead impact 相似文献
43.
E Girbal-Neuhauser JJ Durieux M Arnaud P Dalbon M Sebbag C Vincent M Simon T Senshu C Masson-Bessière C Jolivet-Reynaud M Jolivet G Serre 《Canadian Metallurgical Quarterly》1999,162(1):585-594
Antifilaggrin autoantibodies (AFA) are a population of IgG autoantibodies associated to rheumatoid arthritis (RA), which includes the so-called "antikeratin" Abs and antiperinuclear factor. AFA are the most specific serological markers of RA. We previously showed that they recognize human epidermal filaggrin and other profilaggrin-related proteins of various epithelial tissues. Here, we report further characterization of the protein Ags and epitopes targeted by AFA. All the Ags that exhibit numerous neutral/ acidic isoelectric variants were immunochemically demonstrated to be deiminated proteins. In vitro deimination of a recombinant human filaggrin by a peptidylarginine deiminase generated AFA epitopes on the protein. Moreover, two of three filaggrin-derived synthetic peptides with a citrulline in the central position were specifically and widely recognized by AFA affinity-purified from a series of RA sera. These results indicate that citrulline residues are constitutive of the AFA epitopes, but only in the context of specific amino acid sequences of filaggrin. In competition experiments, the two peptides abolished the AFA reactivity of RA sera, showing that they present major AFA epitopes. These data should help in the identification of a putative deiminated AFA-inducing or cross-reactive articular autoantigen and provide new insights into the pathogenesis of RA. They could also open the way toward specific immunosuppressive and/or preventive therapy of RA. 相似文献
44.
The paraxial ray theory applied to randomly distorted multimode optical fibers in Part I is applied here to step-index fibers with microbending. This technique provides a stationary microbending loss equal to 6,27 λ/Δ dB/unit length, where γ denotes the spectral density of the curvature process and Δthe relative index change. The product of the square of the bandwidth improvement factor by the loss in dB is equal to 0,74 dB. The role of the distortion on bandwidth is illustrated for a 10 km long fiber, excited by a lambertian source. 相似文献
45.
The study of the morphology of eggs, larvae, pupae and adults of Aedes excrucians from Germany, Italy and France has led the authors to rise again the binomen Aedes surcoufi (Theobald, 1912) to particularize the european populations. At the same time, the characteristics of the different species of the Aedes excrucians complex are discussed. 相似文献
46.
Smet C Leroy A Sillen A Wieruszeski JM Landrieu I Lippens G 《Chembiochem : a European journal of chemical biology》2004,5(12):1639-1646
A combined strategy to obtain a partial NMR assignment of the neuronal Tau protein is presented. Confronted with the extreme spectral degeneracy that the spectrum of this 441 amino acid long unstructured protein presents, we have introduced a graphical procedure based on residue type-specific product planes. Combining this strategy with the search for pairwise motifs, and combining the spectra of different Tau isoforms and even of peptides derived from the native sequence, we arrive at a partial assignment that is sufficient to map the interactions of Tau with its molecular partners. The obtained assignments equally confirm the absence of regular secondary structure in the isolated protein. 相似文献
47.
Amatore C Chovin A Garrigue P Servant L Sojic N Szunerits S Thouin L 《Analytical chemistry》2004,76(24):7202-7210
Dynamic concentration profiles within the diffusion layer of an electrode were imaged in situ using fluorescence detection through a multichannel imaging fiber. In this work, a coherent optical fiber bundle is positioned orthogonal to the surface of an electrode and is used to report spatial and temporal micrometric changes in the fluorescence intensity of an initial fluorescent species. The fluorescence signal is directly related to the local concentration of a redox fluorescent reagent, which is electrochemically modulated by the electrode. Fluorescence images are collected through the optical fiber bundle during the oxidation of tris(2,2'-bipyridine)ruthenium(II) to ruthenium(III) at a diffusion-limited rate and allow the concentration profiles of Ru(II) reagent to be monitored in situ as a function of time. Tris(2,2'-bipyridine)ruthenium(II) is excited at 485 nm and emits fluorescence at 605 nm, whereas the Ru(III) oxidation state is not fluorescent. Our experiments emphasize the influence of two parameters on the micrometer spatial resolution: the numerical aperture of optical fibers within the bundle and the Ru(II) bulk concentration. The extent of the volume probed by each individual fiber of the bundle is discussed qualitatively in terms of a primary inner-filter effect and refractive index gradient. Experimentally measured fluorescence intensity profiles were found to be in very good agreement with concentration profiles predicted upon considering planar diffusion and thus validate the concept of this new application of imaging fibers. The originality of this remote approach is to provide a global view of the entire diffusion layer at a given time through one single image and to allow the time expansion of the diffusion layer to be followed quantitatively in real time. 相似文献
48.
Aerosol lidar intercomparison in the framework of the EARLINET project. 1. Instruments 总被引:1,自引:0,他引:1
Matthais V Freudenthaler V Amodeo A Balin I Balis D Bösenberg J Chaikovsky A Chourdakis G Comeron A Delaval A De Tomasi F Eixmann R Hågård A Komguem L Kreipl S Matthey R Rizi V Rodrigues JA Wandinger U Wang X 《Applied optics》2004,43(4):961-976
In the framework of the European Aerosol Research Lidar Network to Establish an Aerosol Climatology (EARLINET), 19 aerosol lidar systems from 11 European countries were compared. Aerosol extinction or backscatter coefficient profiles were measured by at least two systems for each comparison. Aerosol extinction coefficients were derived from Raman lidar measurements in the UV (351 or 355 nm), and aerosol backscatter profiles were calculated from pure elastic backscatter measurements at 351 or 355, 532, or 1064 nm. The results were compared for height ranges with high and low aerosol content. Some systems were additionally compared with sunphotometers and starphotometers. Predefined maximum deviations were used for quality control of the results. Lidar systems with results outside those limits could not meet the quality assurance criterion. The algorithms for deriving aerosol backscatter profiles from elastic lidar measurements were tested separately, and the results are described in Part 2 of this series of papers [Appl. Opt. 43, 977-989 (2004)]. In the end, all systems were quality assured, although some had to be modified to improve their performance. Typical deviations between aerosol backscatter profiles were 10% in the planetary boundary layer and 0.1 x 10(-6) m(-1) sr(-1) in the free troposphere. 相似文献
49.
Abdellatif?EnnajiEmail author Arnaud?Ribert Yves?Lecourtier 《International Journal on Document Analysis and Recognition》2003,6(1):1-9
This article describes an approach to designing a distributed and modular neural classifier. This approach introduces a new hierarchical clustering that enables one to determine reliable regions in the representation space by exploiting supervised information. A multilayer perceptron is then associated with each of these detected clusters and charged with recognizing elements of the associated cluster while rejecting all others. The obtained global classifier is comprised of a set of cooperating neural networks and completed by a K-nearest neighbor classifier charged with treating elements rejected by all the neural networks. Experimental results for the handwritten digit recognition problem and comparison with neural and statistical nonmodular classifiers are given.Received: 1 October 2002, Accepted: 21 November 2002, Published online: 6 June 2003 相似文献
50.
Mohamad El Khatib Arnaud Pothier Aurelian Crunteanu Pierre Blondy 《Microsystem Technologies》2007,13(11-12):1457-1461
This paper reports the design of a hermetic-compatible wafer-scale package for RF MEMS based components. The presented packaging concept consists in encapsulating the whole RF device or subsystem instead of encapsulating each MEMS component separately, which will reduce the device size and cost. This approach is based on the MEMS fabrication technology on ceramic substrate and the use of laser drilled vias hole techniques to realize full metallized vias in alumina substrates. These vias holes will allow a low loss RF signal transmission inside the package without breaking its hermeticity. Hence, several packaged switching networks prototypes, based on ohmic contact MEMS switches, have been designed following this approach and the packaging electromagnetic impact on these components has been especially studied to result on good performance devices. 相似文献