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Many of the striking similarities which occur for the adjoint representation of groups in the exceptional series (cf. [1–3]) also occur for certain representations of specific reductive subgroups. The tensor algebras on these representations are easier to describe (cf. [4,5,7]), and may offer clues to the original situation.The subgroups which occur form a Magic Triangle, which extends Freudenthal's Magic Square of Lie algebras. We describe these groups from the perspective of dual pairs, and their representations from the action of the dual pair on an exceptional Lie algebra. To cite this article: P. Deligne, B.H. Gross, C. R. Acad. Sci. Paris, Ser. I 335 (2002) 877–881.  相似文献   
187.
Results of a coherent digital-subcarrier multiplexed (SCM) lightwave system are described. Five frequency-shift-keyed channels at 100 Mb/s each were transmitted using microwave subcarriers. With a phase modulation index of β=0.19, a bit error rate of 10-9 was achieved with a detected optical power of -33 dBm. This is a 14-dB improvement in receiver sensitivity over a comparable direct-detection SCM system  相似文献   
188.
In this work, we present a new method for in vivo endolaryngeal contactpressure measurement with a miniature pressure transducer. Using this methodology, contact pressures can be measured during videoendoscopy at different locations between the artyenoids and also at various locations along the membranous vocal folds. Twenty adults with organic and functional voice disorders and two vocally healthy adults participated as subjects. Endolaryngeal contact pressure measures were made during a series of phonatory tasks varying pitch, loudness, and phonatory onset and offset. Measures were also made during nonphonatory tasks, including throat clearing, coughing, Valsalva maneuvres, and gagging. The most remarkable findings were: (1) interarytenoid contact pressures were considerably greater than intraglottal contact pressures; (2) interarytenoid contact pressures were greater for lower than higher pitches; (3) both interarytenoid and intraglottal contact pressures were remarkably large during hard glottal attack; and (4) overall, the largest endolaryngeal pressures were recorded between the arytenoids, during a thoracic fixation maneuver and during gag reflex.This work was supported in part by Deutsche Forschungsgemeinschaft (He 2869/1-1), by a grant from the “Verein zur Förderung hör-, sprach- und stimmgestörter Patienten an der FU Berlin e.V.” (nonprofit organization), Berlin, Germany, and by Grant No. K08 DC00139 from the National Institute on Deafness and Other Communication Disorders.  相似文献   
189.
Not all rational numbers are possibilities for the average genus of an individual graph. The smallest such numbers are determined, and varied examples are constructed to demonstrate that a single value of average genus can be shared by arbitrarily many different graphs. It is proved that the number 1 is a limit point of the set of possible values for average genus and that the complete graph K4 is the only 3-connected graph whose average genus is less than 1.  相似文献   
190.
The authors employ a two-step solution: first, produce an aggregate forecast for each data service for each geographical area; then, these aggregate forecasts are broken down into forecasts of demand for broadband data services within and between the geographical areas  相似文献   
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