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Antennes     
Didier Lombard 《电信纪事》1989,44(9-10):443-444
  相似文献   
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The authors developed a model on optical guided structures with complex refractive indices, on 9 desktop-computer. This model allows to predict the coupling efficiency of photodetectors monolithically integrated with optical waveguides. An oscillatory behaviour of the absorption coefficient versus the absorbing layer thinkness has been pointed out. Comparisons with experimental resuylts obtained with device made in different laboratories show a good agrement  相似文献   
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This paper focuses on flow lines composed of multiple parallel-machine stages. The system is similar to a classical flow line, the only difference being that a given stage may consist of parallel machines. A method for modeling and analyzing this type of flow lines is presented. The technique used amounts to replacing each parallel-machine stage by a single equivalent machine in order to obtain a classically-structured flow line with machines in series. Equations for computing the parameters of equivalent machines are submitted. These parameters can then be used to carry out performance diagnosis of the corresponding stage, or as input data for existing analysis methods to evaluate the production performance of flow lines. The method presented in this paper has been successfully implemented and tested in the industry over the past few years.  相似文献   
86.
This paper presents an innovating real time method for detecting road obstacles by on board stereovision. After having exposed the stakes of the obstacles detection, having presented the state of the art and having identified the problems to be solved, the developed approach is described. It is based on the analysis of the “v-disparity” image, which provides a suitable representation of the geometric content of the road scene. The method is then evaluated with respect to the problems generally affecting stereovision approaches. The theoretical good properties of the “v-disparity” algorithm — genericity, effectiveness, robustness, and computational efficiency — are thus experimentally confirmed. Thanks to the performances obtained, the described algorithm is used for on board driving assistance applications.  相似文献   
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Ferrociphenols have been found to have high antiproliferative activity against estrogen‐independent breast cancer cells. The rat and human liver microsome‐mediated metabolism of three compounds of the ferrocifen ( FC ) family, 1,1‐bis(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC1 ), 1‐(4‐hydroxyphenyl)‐1‐(phenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC2 ), and 1‐[4‐(3‐dimethylaminopropoxy)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC3 ), was studied. Three main metabolite classes were identified: quinone methides ( QM s) deriving from two‐electron oxidation of FC s, cyclic indene products ( CP s) deriving from acid‐catalyzed cyclization of QM s, and allylic alcohols ( AA s) deriving from hydroxylation of FC s. These metabolites are generated by cytochromes P450 (P450s), as shown by experiments with either N‐benzylimidazole as a P450 inhibitor or recombinant human P450s. Such P450‐dependent oxidation of the phenol function and hydroxylation of the allylic CH2 group of FC s leads to the formation of QM and AA metabolites, respectively. Some of the new ferrociphenols obtained in this study were found to exhibit remarkable antiproliferative effects toward MDA‐MB‐231 hormone‐independent breast cancer cells.  相似文献   
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