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81.
Sven Verdoolaege Martin Palkovič Maurice Bruynooghe Gerda Janssens Francky Catthoor 《Journal of Electronic Testing》2010,26(2):279-292
The application of loop and data transformations to array and loop intensive programs is crucial to obtain a good performance.
Designers often apply these transformations manually or semi-automatically. For the class of static affine programs, automatic
methods exist for proving the correctness of these transformations. Realistic multimedia systems, however, often contain constructs
that fall outside of this class. We present an extension of a widening based approach to handle the most relevant of these
constructs, viz. accesses to array slices, data dependent accesses and data dependent assignments, and report on some experiments
with non-trivial applications. 相似文献
82.
Dantigny P Guilmart A Bensoussan M 《International journal of food microbiology》2005,100(1-3):187-196
For over 20 years, predictive microbiology focused on food-pathogenic bacteria. Few studies concerned modelling fungal development. On one hand, most of food mycologists are not familiar with modelling techniques; on the other hand, people involved in modelling are developing tools dedicated to bacteria. Therefore, there is a tendency to extend the use of models that were developed for bacteria to moulds. However, some mould specificities should be taken into account. The use of specific models for predicting germination and growth of fungi was advocated previously []. This paper provides a short review of fungal modelling studies. 相似文献
83.
Iucci L Patrignani F Belletti N Ndagijimana M Elisabetta Guerzoni M Gardini F Lanciotti R 《Meat science》2007,75(4):669-675
The aim was to study the effects of Debaryomyces hansenii and Yarrowia lipolytica strains, used with lactic acid starter cultures (Lactobacillus plantarum), in the manufacture of dried fermented sausages in order to understand their effects on volatile profile, biogenic amine content and sensory properties. The experimental data showed that every yeast strain produced a specific profile of volatile metabolic products. The yeasts also gave sausages with distinctive sensory properties. The degree of mincing also influenced these properties, but none of these factors had significant influence upon the accumulation of biogenic amines. 相似文献
84.
Natanaël Basile Maurice Gonon Fabrice Petit Francis Cambier 《Journal of the European Ceramic Society》2012,32(12):3303-3311
The research work reported in this paper is an investigation of the behavior of barium titanate powders under selective laser irradiation. Our goal is to determine suitable conditions to sinter the powders and form dense layers usable in some electronic components. On that purpose, compacts of micro/nano BaTiO3 powder mixes are used for a parametric investigation of the laser scans parameters (power, speed, etc.) with a Nd-YVO4 laser (23 W). The microstructures obtained after laser treatments are evaluated by XRD, SEM and EDS and compared to a reference specimen manufactured in a conventional way. From this work it can be concluded that a high laser beam power is required to obtain a consolidation of the powder grains and the use of a high scan speed avoids the melting. The scanning speed also influences the final crystallographic state of BaTiO3. Optimal parameters were founded in order to form a dense and homogeneous tetragonal BaTiO3 surface. 相似文献
85.
Belén Díaz Emma Härkönen Jolanta ?wiatowska Vincent Maurice Antoine Seyeux Philippe Marcus Mikko Ritala 《Corrosion Science》2011,(6):2168-2175
ToF-SIMS, XPS, voltammetry and EIS investigation of the anti-corrosion properties of thin (10, 50 and 100 nm) alumina coatings grown by atomic layer deposition at 160 °C on steel is reported. Surface analysis shows a thickness-independent Al2O3 stoichiometry of the coating and trace contamination by the growth precursors. The buried coating/alloy interface has iron oxide formed in ambient air and/or resulting from the growth of spurious traces in the initial stages of deposition. Electrochemical analysis yields an exponential decay of the coating porosity over four orders of magnitude with increasing thickness, achieved by sealing of the more defective first deposited 10 nm. 相似文献
86.
Flavio P. Junqueira Keith Marzullo Maurice Herlihy Lucia Draque Penso 《Distributed Computing》2010,23(2):135-149
Many replication protocols employ a threshold model when expressing failures they are able to tolerate. In this model, one assumes that no more than t out of n components can fail, which is a good representation when failures are independent and identically distributed (IID). In many
real systems, however, failures are not IID, and a straightforward application of threshold protocols yields suboptimal results.
Here, we examine the problem of transforming threshold protocols into survivor-set protocols tolerating dependent failures.
Our main goal is to show the equivalence between the threshold model and the core/survivor set model. Toward this goal, we
develop techniques to transform threshold protocols into survivor set ones. Our techniques do not require authentication,
self-verification or encryption. Our results show in one case that we can transform a threshold protocol to a subset by spreading
a number of processes across processors. This technique treats a given threshold algorithm as a black box, and consequently
can transform any threshold algorithm. However, it has the disadvantage that the transformation is not possible for all sets
of survivor sets. The second technique instead focuses on transforming voters: functions that evaluate to a value out of a set of tallied values in a replication protocol. Voters are an essential part
of many fault-tolerant protocols, and we show a universal way of transforming them. With such a transformation we expect that
a large number of protocols in the literature can be directly transformed with our technique. It is still an open problem,
however, if the two models are equivalent, and our results constitute an important first step in this direction. 相似文献
87.
Dr. Tobias Krämer Dr. Mario Kampa Prof. Dr. Dr. Wolfgang Lubitz Dr. Maurice van Gastel Prof. Dr. Frank Neese 《Chembiochem : a European journal of chemical biology》2013,14(14):1898-1905
[NiFe] hydrogenases catalyze the reversible oxidation of dihydrogen. The corresponding catalytic cycle involves a formidable number of redox states of the Ni‐Fe active site; these can be distinguished experimentally by the IR stretching frequencies of their CN and CO ligands coordinated to iron. These spectroscopic fingerprints serve as sensitive probes for the intrinsic electronic structure of the metal core and, indirectly, for the structural composition of the active site. In this study, density functional theory (DFT) was used to calculate vibrational frequencies, by focusing on the EPR‐silent intermediate states that contain divalent metal centers. By using the well‐characterized Ni‐C and Ni‐B states as references, we identified candidates for the Ni‐SIr, Ni‐SIa, and Ni‐R states by matching the predicted relative frequency shifts with experimental results. The Ni‐SIr and Ni‐SIa states feature a water molecule loosely bound to nickel and a formally vacant bridge. Both states are connected to each other through protonation equilibria; that is, in the Ni‐SIa state one of the terminal thiolates is protonated, whereas in Ni‐SIr this thiolate is unprotonated. For the reduced Ni‐R state two feasible models emerged: in one, H2 coordinates side‐on to nickel, and the second features a hydride bridge and a protonated thiolate. The Ni‐SU state remains elusive as no unequivocal correspondence between the experimental data and calculated frequencies of the models was found, thus indicating that a larger structural rearrangement might occur upon reduction from Ni‐A to Ni‐SU and that the bridging ligand might dissociate. 相似文献
88.
Knight Raymond A.; Manoach Dara S.; Elliott David S.; Hershenson Maurice 《Canadian Metallurgical Quarterly》2000,109(4):575
The hypothesis that the perceptual organization dysfunction of patients with poor premorbid schizophrenia is due to a deficit in global visual sensory store processing was tested by assessing their ability to process symmetrical configurations that develop early and have strong prepotent structures. Two same–different judgment tasks in which performance varies as a function of the symmetrical organization and task demands were administered to participants with good and poor premorbid schizophrenia, those with mood disorders, and normal controls. Like the other groups, poor premorbid schizophrenics' latency and error response patterns closely paralleled the a priori model of adequate processing. The results support their competence in perceptually processing symmetrical configurations and disconfirm the hypothesis that their input deficiencies represent a general deficiency in all forms of perceptual organization. The implications for specifying their early input dysfunction are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Conrod Patricia J.; Stewart Sherry H.; Pihl Robert O.; C?té Sylvana; Fontaine Veronique; Dongier Maurice 《Canadian Metallurgical Quarterly》2000,14(3):231
Female substance abusers recruited from the community were randomly assigned to receive 1 of 3 brief interventions that differentially targeted their personality and reasons for drug use. The 90-min interventions were: (a) a motivation-matched intervention involving personality-specific motivational and coping skills training, (b) a motivational control intervention involving a motivational film and a supportive discussion with a therapist, and (c) a motivation-mismatched intervention targeting a theoretically different personality profile. Assessment 6 months later (N?=?198) indicated that only the matched intervention proved to be more effective than the motivational control intervention in reducing frequency and severity of problematic alcohol and drug use and preventing use of multiple medical services. These findings indicate promise for a client-treatment matching strategy that focuses on personality-specific motives for substance abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.