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排序方式: 共有1305条查询结果,搜索用时 15 毫秒
111.
Julien Jumel Michal K. Budzik Martin E.R. Shanahan 《Engineering Fracture Mechanics》2011,78(18):3253-3269
A first order correction is proposed taking into account both interface elasticity and transverse anticlastic curvature of flexible substrate(s) in the DCB (and related tests). Adherends are represented by Kirchhoff–Love plates, and the interface by a Winkler-type elastic foundation. Two functions are introduced, representing evolution of beam deflection along the sample midline and anticlastic curvature along the plate. A method of virtual work is used to find the associated equilibrium equation. The two-dimensional sample deformation is determined semi-analytically. Sample rigidity and energy release rate are computed for various geometrical configurations and compared to more common models. 相似文献
112.
This paper reports the first stage of work being undertaken to understand the factors that have impacted on the current state of food safety in the UK food manufacturing sector. The paper first explores developments in international food safety regulation in general and in particular, the UK. Using a survey and case study methodology, the paper examines the response of food manufacturing enterprises to food safety regulation, and uses statistical techniques to investigate the effects of enterprise size on the drivers for, benefits of, and challenges to compliance. Further, the factors that influence the successful implementation of an integrated food safety management system are also examined. The results show a great deal of both statutory and private regulation that has incentivised enterprises. In response, enterprises have implemented integrated food safety management systems to proactively deal with the risks associated with food safety, however, enterprises claim that statutory regulations are biased towards consumers, without adequate impact assessments on all stakeholders within the chain, and hence causing industry to incur significant costs that could otherwise be avoided. Even though compliance with food safety regulation is burdensome, the cost of non-compliance will also be significant to enterprises. The findings also show that there is no significant effect of size of enterprise on the drivers, benefits and challenges to compliance with food safety regulation. 相似文献
113.
114.
The learning of complex relationships can be decomposed into several neural networks. The modular organization is determined
by prior knowledge of the problem that permits to split the processing into tasks of small dimensionality. The sub-tasks can
be implemented with neural networks, although the learning examples cannot be used anymore to supervise directly each of the
networks. This article addresses the problem of learning in a modular context, developing in particular additive compositions. A simple rule allows defining efficient training, and combining, for example, several Supervised-SOM networks. This technique
is important because it introduces interesting generalizations in many modular compositions, permitting data fusion or sequential
combinations of neural networks.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
115.
Reference materials (RM) play an increasingly important role for laboratories. The aim of this work is to compare different
conditions of storage and assess the stability of agrifood external reference materials (ERM). These materials could be used
as tools by laboratories notably for their quality control procedure. However, as the other RM, their stability must be assessed
during stability studies. The determination of the limiting date of stability (LDS), defined as the period during which analytes
called marker of stability are still considered as stable, is used on this purpose. The influences of the environmental factor
were tested by the application of full experimental designs with two tested environmental factors: the temperature (storage
at +4 °C or +20 ± 10 °C) and the composition of the atmosphere (absence or presence of gases in the packaging). Thus, the
setting under vacuum increases clearly the stability for the studied analyte. Almost all ERM stored in the best conditions
have a determined LDS higher than those stored in current condition of storage. Indeed, the bread wheat ERM LDS is higher
than the current storage of 24 months 相似文献
116.
117.
D Gaudet MC Vohl P Julien G Tremblay P Perron C Gagné J Bergeron S Moorjani JP Després 《Canadian Metallurgical Quarterly》1998,82(3):299-305
A possible future clinical application of NMDA receptor antagonists is the control of the development of opiate analgesic tolerance. Therefore, the ability of NMDA receptor antagonists to modify the acute analgesic effects of opiates becomes increasingly important. The present study sought to evaluate the analgesic potency of combined administration of morphine (5-20 mg/kg) and a competitive NMDA receptor antagonist D-CPPene (SDZ EAA 494; 3-(2-carboxypiperazin-4-yl)-1-propenyl-1-phosphonic acid; 0.3-5.6 mg/kg) in the tail-flick and tail-pinch tests with rats. It was found that D-CPPene significantly increased the duration of morphine analgesia, but there was hardly any evidence for potentiation of morphine analgesia shortly after morphine administration. This effect could only in part be attributed to the D-CPPene-induced disruption of the development of 'learned hyperresponsiveness' (i.e., acquisition of decreased latencies to escape from repeated exposures to noxious stimulation). In addition, the plasma concentration of morphine was not affected by concurrent treatment with D-CPPene. 相似文献
118.
We introduce a new higher-order rewriting formalism, called expression reduction systems with patterns (ERSP), where abstraction is allowed not only on variables but also on nested patterns with metavariables. These patterns are built
by combining standard algebraic patterns with choice constructors denoting cases. In other words, the nondeterministic choice between different rewrite rules which is inherent
to classical rewriting formalisms can be lifted here to the level of patterns. We show that confluence holds for a reasonable
class of systems and terms. 相似文献
119.
K. Zaghib P. Charest A. Guerfi A. Mauger C.M. Julien 《Journal of power sources》2010,195(24):8280-8288
LiFePO4 (LFP) particles were obtained by grinding ingot synthesized in the molten state. This process, followed by jet milling, and then wet milling, provides a simple way to obtain powders with controlled particle size in the range from macroscopic to 25 nm. However, at this time, we find that these particles tend to agglomerate to form secondary particles of size ∼100 nm. The particles obtained by this process are characterized by X-ray diffraction (XRD). In situ and ex situ scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effect of milling was also investigated by analysis of physical properties using infrared spectroscopy (FTIR) and magnetic measurements. The electrochemical performance was evaluated in cells containing Li/1 M LiPF6 in EC:DEC (1:1)/C-LiFePO4. After carbon coating, the LFP particles which are free of impurities, exhibit high-rate capability. Even with a limited amount of carbon (2 wt.%) appropriate for commercial batteries, the capacity is 157 mAh g−1 at 0.1 C, 120 mAh g−1 at 10 C, without capacity fading after 60 cycles. 相似文献
120.