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401.
402.
The usual way to study the local structure of Equilibrium State of an Axiom-A diffeomorphism or flow is to use the symbolic dynamic and to push results on the manifold. A new geometrical method is given. It consists in proving that Equilibrium States for Hölder-continuous functions are related to other Equilibrium States of some special sub-systems satisfying a sort of expansiveness. Using different kinds of extensions the local product structure of Gibbs-measure is proven.

  相似文献   

403.
404.
This paper addresses the problem of optimizing the transportation of disabled persons from home to specialized centres or schools. It is modelled as a Dial-a-ride problem (DARP), where several people share the same destination. Particular emphasis is placed on the objective function in order to consider several potentially conflicting interests. We propose a multi-criteria model from Multi-attribute Utility Theory based on the Choquet integral. The resulting multi-criteria DARP is then solved with a large neighbourhood search algorithm. This method includes classical destroy and repair heuristics as well as new operators exploiting the shared destination feature and criterion-specific operators. The algorithm is evaluated on a set of 14 real-world instances in the field of health care logistics, with up to 200 requests and 51 destination points.  相似文献   
405.
Two preparatively attractive methods for the azidation of alkyl radicals are described. Secondary and tertiary alkyl iodides and dithiocarbonates are easily converted into the corresponding azides, either by reaction with ethanesulfonyl azide in the presence of dilauroyl peroxide, or by treatment with benzenesulfonyl azide and hexabutylditin in the presence of a radical initiator. Interestingly, intramolecular tandem radical cyclization-azidation processes can be performed in high yields.  相似文献   
406.
Network and system concepts for optical packet switching   总被引:4,自引:0,他引:4  
An overview of the characteristics and challenges of optical packet switching is given, illustrating its potential advantages within future nodes and networks, describing basic system functionalities. The opportunities introduced by the ACTS KEOPS project on all-optical packet-switching networks are highlighted, based partially on the outcome of the RACE ATMOS project, which is also considered in this article  相似文献   
407.
Gas adsorption at 77 K is probably the most widely used method to characterize mesoporous adsorbents via capillary condensation. Mercury intrusion is also commonly used for the characterization of such materials with the possibility to extend the pore width distribution measurement to the macropore range. More recently water intrusion was proposed to study hydrophobic porous solids. Thermoporometry is a further characterization method, now based on the study of the solid/liquid transition. We can consider that all these methods rely on the modification of the phase diagram of a pure substance under the effect of confinement. For each of them, the equations and models derived are based either on classical thermodynamics or on statistical approaches. In most cases, the derivation of the pore width distribution is carried out with the assumption that the porous system is made up of non‐connected cylinders, whereas the actual complexity of the structure is derived from the hysteresis shape. Our aim here is to compare the four approaches above (gas adsorption, mercury intrusion, water intrusion, thermoporometry) on samples giving rise, in their gas adsorption isotherms, to the typical hysteresis loops of the IUPAC classification. Our comparison is in great part carried out after the shape of the hysteresis loops obtained with the various methods and after the information it brings on the mechanism of replacement of a phase by the other within the porous system.  相似文献   
408.
It is pointed out that extremely high coupling efficiencies can be achieved on passive structures which simulate an integrated waveguide amplifier. The bundle integrated guide (BIG) configuration exhibits a coupling efficiency of 95% per interface, which is in perfect agreement with the theoretical prediction. This coupling efficiency has been determined by measuring 38 monolithically integrated BIG structures  相似文献   
409.
This investigation presents a synthesis of two multicriteria analysis methods, Rough Set Method (RSM) and Net Flow Method (NFM), applied to the multicriteria optimisation for the manufacture of paper using jack pine as the source of fibres. This work is the result of a collaboration between different Canadian and French laboratories.  相似文献   
410.
Monolithic integration of two optical switches consisting in carrier depletion directional couplers based on GaInAsP/InP double heterostructure waveguides, with two GaInAs p-i-n detectors has been realized on semi-insulating InP. Packaged devices based on 2 mm coupling length directional couplers exhibit a switching voltage of -15 V and a 3 dB cutoff frequency of 1.3 GHz. Also, total fiber-to-fiber insertion loss of only 16 dB is achieved without any antireflection coating  相似文献   
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