Multiplexing

Heilmeier displays can be multiplexed only for low levels, as the threshold characteristic is not sharp enough for high level multiplexing. The 90° twisted geometry provides 

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An improved signal/noise ratio because all signals are seen simultaneptisiy along with the instrument s own noise (called the multiplex or Fellgett advantage). 

Multiplex wellhead high-pressure control pump valve... 

Posgay, G. and Imre, L. Detection of Stresses Using Multiplex Barkhausen Noise Measuring Equipment Proc. 8 th DAS on Experimental Methods in Solid Mechanics, Godollo, 1991, Edited 1.. Huszdr, pp. 19-19/2... 

All motions are insured by six stepping motors sequentially driven by a programmable translator-indexer device fitted with a power multiplexer. 

These two transducer pairs are activated alternating. For this purpose an ultrasonic instrument is combined with a two channel multiplexer. Figure 8 presents a modified standard instrument USN52 which also implies a modified software. This system performs four measurements per second - alternating the velocity and the thickness are determined. The probe can be scanned over the surface and in every position both, the velocity and the wall thickness are indicated Using the serial interface of the instrument finally a two-dimensional map of velocity or thickness can be generated. 

Fig. 8 Ultrasonic instrument USN52 with a two channel multiplexer...

In the case of the Superphenix probes we were asked to provide a 100% characterization of the probes, that meant to verify all acoustics characteristics over the 160 groups of element multiplexed around the probe. This task has required the development of an automatic acquisition and analysis system which is described below. 

Measurement at 500 m/min was considered so promising that it was decided to manufacture and test a prototype for the four channel scanning system. In such a system multiplexing of signals from the four transducers to one ultrasonic instrument was a possibility. Alternatively four independent instruments (one for each transducer) could be used in the scanning system. 

Unlike the typical laser source, the zero-point blackbody field is spectrally white , providing all colours, CO2, that seek out all co - CO2 = coj resonances available in a given sample. Thus all possible Raman lines can be seen with a single incident source at tOp Such multiplex capability is now found in the Class II spectroscopies where broadband excitation is obtained either by using modeless lasers, or a femtosecond pulse, which on first principles must be spectrally broad [32]. Another distinction between a coherent laser source and the blackbody radiation is that the zero-point field is spatially isotropic. By perfonuing the simple wavevector algebra for SR, we find that the scattered radiation is isotropic as well. This concept of spatial incoherence will be used to explain a certain stimulated Raman scattering event in a subsequent section. 

Plenary 10. Hiro-o Hamaguchi, e-mail address lilrama ,chem.s.u-tokvo.ac.ip (time and polarization resolved multiplex 2D-CARS). Two-dimensional (tune and frequency) CARS using broadband dye source and streak camera timing. Studies dynamic behaviour of excited (pumped) electronic states. Follows energy flow within excited molecules. Polarization control of phase of signal (NR background suppression). 

Toleutaev B N, Tahara T and Hamaguchi H 1994 Broadband (1000 cm multiplex CARS spectroscopy application to polarization sensitive and time-resolved measurements Appl. Phys. 59 369-75... 

As in all Fourier transform methods in spectroscopy, the FTIR spectrometer benefits greatly from the multiplex, or Fellgett, advantage of detecting a broad band of radiation (a wide wavenumber range) all the time. By comparison, a spectrometer that disperses the radiation with a prism or diffraction grating detects, at any instant, only that narrow band of radiation that the orientation of the prism or grating allows to fall on the detector, as in the type of infrared spectrometer described in Section 3.6. 

A more recent, and superior, type of detector, which also benefits from the multiplex advantage, is the charge-coupled device (CCD). The CCD, as used for spectroscopy, has been developed from the CCD detector used in a camcorder. 

Fig. 15. Erbium-doped fiber amplifier where x represents spHces and WDM is a wavelength division multiplexer combining the signal and pump...

Fig. 8. Holographic data storage experimental results photographs of holographic reconstmctions from a multiplexed hologram (51).

Fig. 9. Holographic pattern recognition system, (a) Recording an angularly multiplexed hologram (b) forming correlation outputs using arbitrary input...

Another possible advantage of the PHB method is its potential multiplexing characteristics by synchronous recording and read-out, exceptional data transfer rates can be achieved. These high transfer rates are of equal importance in practical data technology as high storage densities. 

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