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1.
François Lepage 《Logica Universalis》2016,10(2-3):327-338
In this paper, we introduce a Hilbert style axiomatic calculus for intutionistic logic with strong negation. This calculus is a preservative extension of intuitionistic logic, but it can express that some falsity are constructive. We show that the introduction of strong negation allows us to define a square of opposition based on quantification on possible worlds. 相似文献
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A?ta Thior Anne-Claire Lepage Xavier Begaud Olivier Maas 《Applied Physics A: Materials Science & Processing》2012,109(4):1095-1101
This paper presents an analytical model for CRLH (Composite Right-Left Handed) antennas preliminary design. The objective of this work is to develop a tool to estimate quickly the scattering and radiating characteristics of these CRLH-based structures. The analytical model provides thus a set of parameters which roughly fulfill desired requirements. Afterwards, the antenna designer can refine the CRLH-based antenna performances with full 3D electromagnetic simulation software. 相似文献
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Lepage 《Fresenius' Journal of Analytical Chemistry》1867,6(1):211
Ohne Zusammenfassung 相似文献
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We point out an error in the proof of Nishijima et al. that the Bethe-Salpeter wave function for composite particles, lying on Regge trajectories, is finite. We describe a simple counter-example drawn from non-relativistic quantum mechanics and cite others from field theory. 相似文献
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Zero-one integer programming formulations have been described in the literature to solve a wide range of problems in areas as diverse as capital budgeting, allocation, machine sequencing, etc., but as yet large-scale realistic problems can be very expensive to compute using the standard branch-and-bound extensions to linear programming packages. Many authors, noting that there are many situations in which low-cost approximate solutions may be very acceptable, suggest the use of approximating methods, such as the corresponding linear programme or "effective gradients". This paper describes a complex production scheduling problem for which a near-optimal solution is obtained using a separable programming algorithm.By utilizing the special features of separable programming, the model is able to include considerations of setup times in the optimization. Computational experience suggests that the method is a considerable improvement on heuristic attempts, giving improvements in throughput of approximately 30 per cent. 相似文献
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Yankeelov TE Lepage M Chakravarthy A Broome EE Niermann KJ Kelley MC Meszoely I Mayer IA Herman CR McManus K Price RR Gore JC 《Magnetic resonance imaging》2007,25(1):1-13
PURPOSE: The objective of this study was to assess changes in the water apparent diffusion coefficient (ADC) and in pharmacokinetic parameters obtained from the fast-exchange regime (FXR) modeling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) during neoadjuvant chemotherapy in breast cancer. MATERIALS AND METHODS: Eleven patients with locally advanced breast cancer underwent MRI examination prior to and after chemotherapy but prior to surgery. A 1.5-T scanner was used to obtain T1, ADC and DCE-MRI data. DCE-MRI data were analyzed by the FXR model returning estimates of K(trans) (volume transfer constant), v(e) (extravascular extracellular volume fraction) and tau(i) (average intracellular water lifetime). Histogram and correlation analyses assessed parameter changes post-treatment. RESULTS: Significant (P < .05) changes or trends towards significance (P < .10) were seen in all parameters except tau(i), although there was qualitative reduction in tau(i) values post-treatment. In particular, there was reduction (P < .035) in voxels with K(trans) values in the range 0.2-0.5 min(-1) and a decrease (P < .05) in voxels with ADC values in the range 0.99 x 10(-3) to 1.35 x 10(-3) mm2/s. ADC and v(e) were negatively correlated (r = -.60, P < .02). Parameters sensitive to water distribution and geometry (T(1), v(e), tau(i) and ADC) correlated with a multivariable linear regression model. CONCLUSION: The analysis presented here is sensitive to longitudinal changes in breast tumor status; K(trans) and ADC are most sensitive to these changes. Relationships between parameters provide information on water distribution and geometry in the tumor environment. 相似文献