Based on recent results on the reconstruction of a bandlimited sequence from a nonuniformly decimated version, this paper develops an efficient polyphase structure for such reconstruction. Theoretically, the reconstruction involves the implementation of a bank of multilevel filters, and this paper shows how all these reconstruction filters can be obtained at the cost of one Mth band low-pass fi...

In this paper, we introduce a method by which we can find a close connection between the set of prime $z$-ideals of $C(X)$ and the same of $C(Y)$, for some special subset $Y$ of $X$. For instance, if $Y=Coz(f)$ for some $fin C(X)$, then there exists a one-to-one correspondence between the set of prime $z$-ideals of $C(Y)$ and the set of prime $z$-ideals of $C(X)$ not containing $f$. Moreover, c...

The intrinsic Lyα emission lines of normal galaxies before reionization are much absorbed by the damping wing of the Gunn-Peterson trough, rendering their direct detection nearly impossible, if their intrinsic line widths are less than ∼ 100km/s. High redshift luminous quasars prior to the completion of cosmo-logical reionization at z ∼ 6, on the other hand, are capable of producing large HII r...

Intersymbol interference in direct deIII. FABRY-PEROT INTERFEROMETER tection optical systems can limit the channel spacing We consider a Fabry-Perot filter as the optical demultiplexing in frequency division multiplexing and prevent multifilter [1]. The envelope of the impulse response is well approxlevel signaling. We investigate a zero-forcing electrical imated by e t / ' for t > 0. The envel...

Clusters of galaxies arise from exceptionally high peaks of the primordial fluctuation density field. Their properties as a function of redshift, z, are therefore highly sensitive to the nature of such cosmic fluctuations. It is therefore very important to have a sample of galaxy clusters covering as wide a redshift range as possible. Recently, Olsen et al. (1999) and Scodeggio et al. (1999) ha...

The noise of the frequency-shift signal Δf in noncontact atomic force microscopy (NC-AFM) consists of cantilever thermal noise, tip-surface-interaction noise and instrumental noise from the detection and signal processing systems. We investigate how the displacement-noise spectral density d(z) at the input of the frequency demodulator propagates to the frequency-shift-noise spectral density d(Δ...

We report the discovery of a galaxy at a redshift z = 6.17 identified from deep narrow band imaging and spectroscopic follow-up in one of the CFHT-VIRMOS deep survey fields at 0226-04. In addition to the existing deep BVRI images of this field, we obtained a very deep narrow band image at 920 nm with the aim of detecting Lyα emission at redshift ∼ 6.5. Spectroscopic follow-up of some of the can...

The impact of polarimetric radar data on the estimation of uncertain microphysical parameters is investigated when the effect of uncertain parameters on the observation operators is also considered. Five fundamental microphysical parameters, i.e., the intercept parameters of rain, snow and hail and the bulk densities of snow and hail, are estimated individually or collectively using the ensembl...