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61.
We present two methods of signal deconvolution for systems whose impulse response (wavelet function) can be explicitly determined, and where the goal is to locate short impulses in the presence of strong, reverberation-like interferences.The first method, which we call algebraic deconvolution, differs from other known techniques in two ways: first of all, explicit use of the wavelet function provides more powerful a priori knowledge than the autocorrelation or the power spectrum. Secondly, this method permits to flexibly trade off noise versus resolution.In the second method presented here, we use an analytical model (synthetic wavelet) of the system impulse response to determine an inverse filter.These methods have been developed for video pulse radar signals, and encouraging early results have been obtained. 相似文献
62.
Driving under the influence of cannabis (DUIC) has become a growing concern. Studies investigating the impact of DUIC on traffic safety have shown evidence that, during the acute period of cannabis intoxication, cannabis diminishes driving faculties and is associated with an elevated risk of collision. However, DUIC drivers seem to exhibit a general reckless driving style that may contribute to an over-estimation of DUIC-related collisions among this group. In this study, we investigated DUIC drivers with respect to self-reported dangerous driving habits (e.g., risky driving, aggressive driving and negative emotional driving), behaviours observed in a driving simulator, psychological predictors and crash involvement. Results suggest that DUIC is associated with self-reported and observed risky driving and negative emotional driving. We also found that sensation seeking and impulsivity are independent psychological predictors of DUIC. Finally, a trend suggests that self-reported DUIC is associated with an increased risk of being involved in a car accident, after controlling for dangerous driving and demographic variables. Implications for interventions are discussed. 相似文献
63.
Thierry Klein Isabelle Joumard Jacques Marcus Robert Cubitt 《Journal of Low Temperature Physics》1999,117(5-6):1353-1357
Small Angle Neutron Scattering has been used to observe diffraction from the flux line lattice in the fully isotropic (K, Ba)BiO
3
high T
c
superconductor. We show that the flux lines are ordered into a hexagonal lattice at low field (H < H
e
0.6T H
g (0) where H
g
is the second order vortex glass transition field). The diffracted intensity continuously drops to zero as the field is increased towards H
e
. Those observations are in good agreement with recent theoritical works which suggested that the formation of dislocations becomes favorable above H
e
leading to a glassy structure. The field H
e
lies close to the onset of the second peak in magnetization measurements indicating that this peak is related to the change in the vortex structure. 相似文献
64.
J Haydersah I Chevallier I Rochette C Mouquet-Rivier C Picq T Marianne-Pépin C Icard-Vernière JP Guyot 《Journal of food science》2012,77(8):M466-M472
The potential of tropical starchy plants such as plantain (Musa paradisiaca), breadfruit (Artocarpus communis), and sweet potato (Ipomoea batatas) for the development of new fermented foods was investigated by exploiting the capacity of some lactic acid bacteria to hydrolyze starch. The amylolytic lactic acid bacteria (ALAB) Lactobacillus plantarum A6 and Lactobacillus fermentum Ogi E1 were able to change the consistency of thick sticky gelatinized slurries of these starchy fruits and tubers into semiliquid to liquid products. Consequently, a decrease in apparent viscosity and an increase in Bostwick flow were observed. These changes and the production of maltooligosaccharides confirmed starch hydrolysis. Sucrose in sweet potato was not fermented by strain A6 and poorly fermented by strain Ogi E1, suggesting possible inhibition of sucrose fermentation. In all 3 starchy plants, rapidly digestible starch (RDS) was higher than slowly digestible starch (SDS) and resistant starch (RS) represented between 17% and 30% dry matter (DM). The digestibility of plantain was not affected by fermentation, whereas the RDS content of breadfruit and sweet potato decreased and the RS content increased after fermentation. Practical Application: The characteristics resulting from different combinations of gluten free starchy plants (plantain, breadfruit, sweet potato) and amylolytic lactic acid bacteria (ALAB) offer opportunities to develop new functional fermented beverages, mainly for breadfruit and sweet potato, after further investigation of their formulation, sensory attributes, nutritional, and prebiotic characteristics. 相似文献
65.
Influence of new thermoplastic sizing agents on the mechanical behavior of poly(ether ketone ketone)/carbon fiber composites 下载免费PDF全文
Isabelle Giraud Sophie Franceschi Emile Perez Colette Lacabanne Eric Dantras 《应用聚合物科学杂志》2015,132(38)
In this study, unidirectional poly(ether ether ketone)/carbon fiber (CF) composite sheets were elaborated with unsized, epoxy‐sized, and thermoplastic‐sized CFs by hot‐press molding. The thermoplastic sizings that we used were poly(ether imide) (PEI) and poly(ether ketone ketone) oligomer aqueous dispersions. Scanning electron microscopy observation of the composites freeze fractures showed that unlike unsized or epoxy‐sized CFs, the thermoplastic sizings improved the interaction between the fibers and the matrix. A comparative study of the mechanical relaxations by dynamic mechanical analysis was carried out on the different composites before and after immersion in kerosene. At low temperature, the PEI sizing had a significant influence on the β relaxation, particularly after kerosene immersion. The thermoplastic sizings did not modify the glass‐transition temperature but improved the kerosene resistance on the composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42550. 相似文献
66.
Shea butter solid nanoparticles for curcumin encapsulation: Influence of nanoparticles size on drug loading 下载免费PDF全文
67.
Fabio Casati Maria Grazia Fugini Isabelle Mirbel Barbara Pernici 《Requirements Engineering》2002,7(2):73-106
Workflow management systems are becoming a relevant support for a large class of business applications, and many workflow
models as well as commercial products are currently available. While the large availability of tools facilitates the development
and the fulfilment of customer requirements, workflow application development still requires methodological guidelines that
drive the developers in the complex task of rapidly producing effective applications. In fact, it is necessary to identify
and model the business processes, to design the interfaces towards existing cooperating systems, and to manage implementation
aspects in an integrated way. This paper presents the WIRES methodology for developing workflow applications under a uniform
modelling paradigm – UML modelling tools with some extensions – that covers all the life cycle of these applications: from
conceptual analysis to implementation. High-level analysis is performed under different perspectives, including a business and an organisational perspective. Distribution, interoperability and cooperation with external information systems are considered in this early
stage. A set of “workflowability” criteria is provided in order to identify which candidate processes are suited to be implemented
as workflows. Non-functional requirements receive particular emphasis in that they are among the most important criteria for
deciding whether workflow technology can be actually useful for implementing the business process at hand. The design phase
tackles aspects of concurrency and cooperation, distributed transactions and exception handling. Reuse of component workflows,
available in a repository as workflow fragments, is a distinguishing feature of the method. Implementation aspects are presented
in terms of rules that guide in the selection of a commercial workflow management system suitable for supporting the designed
processes, coupled with guidelines for mapping the designed workflows onto the model offered by the selected system. 相似文献
68.
Poly(butylene succinate‐co‐butylene adipate)/polyethylene oxide blends for controlled release materials: A morphological study 下载免费PDF全文
Amandine Cottaz Fadi Khalil Sophie Galland Fouzia Jbilou Isabelle Adt Pascal Degraeve Catherine Joly 《应用聚合物科学杂志》2016,133(3)
Varying the formulation and processing conditions of polymer blends allows the design of materials with a large range of morphologies. Active materials embedding active compounds in a devoted phase are promising applications of such blends, offering possible various transport properties. In this study, 13 poly(butylene succinate‐co‐butylene adipate) (PBSA)/polyethylene oxide (PEO) blends were extruded in a slit die. Their morphologies were characterized by water extraction (selective PEO dissolution), FTIR spectroscopy, and differential scanning calorimetry. Transport properties were assessed by water vapor permeation and fluorescein release as model migrant. Indeed, the desorption in water of fluorescein (previously entrapped in PEO) was monitored to preliminary investigate the release properties of these materials: two morphologies were obtained (i) pseudo multilayer films made of PEO‐rich layer/PBSA‐rich layer/PEO‐rich layer and (ii) PEO nodules dispersed in the PBSA‐rich matrix for the highest PBSA contents. The first systems were erodible ones with an uncontrolled fast delivery by PEO dissolution whereas the second ones showed a controlled release by permeation through the PBSA matrix from PEO nodules. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42874. 相似文献
69.
Antonio Brogi Jean-Marie Jacquet Isabelle Linden 《Electronic Notes in Theoretical Computer Science》2003,68(3):284
The paper proposes a theoretical study of a coordination language embodying Linda's asynchronous communication primitive with a refined matching mechanism based on pairs composed of attribute names associated with their values. Computations in this language are described by means of an operational semantics, reporting the whole traces of executions. The non-compositionality of this intuitive operational semantics motivates the design of a compositional and fully abstract denotational semantics, which is then exploited for studying program equivalence in this setting. 相似文献
70.
Fecal coliform removal in wastewater treatment plants studied by plate counts and enzymatic methods 总被引:1,自引:0,他引:1
Twelve wastewater treatment plants (WWTPs) were sampled in France and Belgium in 1999 and 2000 in order to estimate the fecal coliform (FC) removal efficiency of various types of treatment. Only one of these WWTPs was equipped with a specific step to eliminate microorganisms (UV disinfection preceded by sand filtration). FC abundance was measured in raw and treated sewage by plate counts on selective medium and rapid beta-D-glucuronidase (GLUase)-based assays. Removal of culturable FC was the most efficient in treatments with high retention time (activated sludge process with nitrification and denitrification, lagooning), in biofiltration and in the treatment with a tertiary disinfection step. GLUase activity measurements showed the same removal pattern as plate counts except for UV disinfection, where no reduction of GLUase activity was measured. Specific loads of culturable FC and GLUase activity, i.e. daily amounts of culturable FC or GLUase activity in sewage per inhabitant-equivalent, were calculated in raw and treated wastewater for the different WWTPs. 相似文献