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Pseudo random sequence

Correlation of the code with itself (autocorrelation) yields only one correlation point in the time domain defined by the sequence and the unit code interval (see Figure 5c) and an otherwise clean baseline. Since the detector in our chromatogram just follows what the sample valve is doing, it also should be a pseudo random sequence and the cross-correlation of input and output is really an autocorrelation and thus yields the single pulse correlogram with an otherwise clean baseline. [Pg.91]

A simple and efficient encryption method for the SCS codebook is the derivation of a cryptographically secure pseudo-random sequence k from the watermark key K, with kn [0,1), and the modification of each component codebook so that... [Pg.6]

Fignre 3. A pseudo-random sequence is defined by the internal state space, the mapping, the iteration, and the initial state. [Pg.19]

FIGURE 7.2 A representative multiplexed DTIMS gating sequence. The ion beam is modulated using a pseudo-random sequence (PRS) derived from a Simplex matrix, which is applied to the BNG. This is mathematically expressed as a multiplication of the original ion mobility spectra (4 ) by the Simplex matrix (S ,). The multiplexed spectrum (T)) is collected at the detector. The deconvoluted data (ip) is recovered by multiplication of the multiplexed spectrum (Tj) with the inverse of the Simplex matrix (S ). [Pg.160]

The starting point is the (pseudo-) randomization function supplied with most computers it generates a rectangular distribution of events, that is, if called many times, every value between 0 and 1 has an equal probability of being hit. For our purposes, many a mathematician s restraint regarding randomization algorithms (the sequence of numbers is not perfectly random because of serial correlation, and repeats itself after a very large number of... [Pg.163]

As stated in the previous section, the major reactant feed was chosen as the manipulated variable. In the trial this feed was subjected to a pseudo-random binary sequence (PRBS) signal in an open loop operation of the process. The results of the trial, plotted in Fig. 2, show a strong -- but delayed -- cross-correlation between the manipulated feed rate and the reactor temperature. Using techniques described by Box and Jenkins (2), a transfer function relating the manipulated variable to the control variable of interest can be developed. The general form of this transfer function is... [Pg.480]

Now let us take a time period of detector signals large enough to encompass the length of the pseudo random binary sequence Injection code which produced It, and cross-correlate It with this Injection code of -1 and 1. [Pg.92]

A special kind of random noise, pseudo random noise, has the special property of not being really random. After a certain time interval, a sequence, the same pattern is repeated. The most suitable random input function used in CC is the Pseudo Random Binary Sequence (PRBS). The PRBS is a logical function, that has the combined properties of a true binary random signal and those of a reproducible deterministic signal. The PRBS generator is controlled by an internal clock a PRBS is considered with a sequence length N and a clock period t. It is very important to note that the estimation of the ACF, if computed over an integral number of sequences, is exactly equal to the ACF determined over an infinite time. [Pg.104]

An alternative method for excitation of nuclei over a range of chemical shifts is by irradiation with a weak, noise-modulated radio-frequency, instead of with strong r.f. pulses. In one realization of this method, protons were irradiated with repetitive sequences of noise that was truly random,162 and, in another,163 fluorine nuclei were excited by pseudo-random noise generated by amplitude modulation of the r.f. with maximum-length sequences of pulses from a computer or shift register (a series of flip-flop devices connected by feedback loops). With the carrier wave suppressed, the latter process is equivalent to phase modulation of the r.f. by+7r/2 radians when the pulse is turned on, and by —ir/2 radians when it is turned off. This method is identical with that used in most broadband, heteronuclear, noise decouplers, except that greater power is required for decoupling. [Pg.55]

M. Blum and S. Micali, How to Generate Cryptographically Strong Sequences of Pseudo Random Bits, SIAM J. Compt, Vol. 13, pp. 850-864, 1984. [Pg.31]

Other complexes that have been used in ethylene-styrene co-polymerizations are 42, which is inactive in styrene homopolymerization but has been claimed to produce ethylene/styrene co-polymers with styrene content in the range 35-87 mol%.6 2 Living ethylene/styrene co-polymerization can be achieved using the MAO-activated complex 43. Although a relatively low amount of styrene was incorporated (about 10 mol%), NMR analysis indicated that trace amounts of pseudo-random tail-to-tail S-S or S-E-S sequences were observed.6 Marks and co-workers showed that bimetallic catalysts based on 44 can effectively yield ethylene/styrene co-polymers and, in contrast to the monometallic CGCs, styrene incorporation can be higher than 50%.664... [Pg.1051]

MQCs are not excited uniformly and the efficiency with which the various orders of MQC are excited depends specifically on the parameters of the spin system (dipolar couplings, scalar couplings, quadrupolar couplings, chemical shifts) in the spin system and the choice of the preparation time t. Many researchers have co-added spectra acquired with different preparation times to ensure that all transitions are observed with reasonable intensity. A number of broadband excitation techniques have been developed,13-15 where the value of t in the preparation sequence has been varied either in a pseudo-random or systematic fashion to achieve a more uniform excitation in the multiple quantum domain. An experimental search method has been used to optimise the delays in the preparation period of the MQ excitation sequence16 and Wimperis17 used average Hamiltonian theory to propose... [Pg.8]


See other pages where Pseudo random sequence is mentioned: [Pg.95]    [Pg.3]    [Pg.4]    [Pg.23]    [Pg.13]    [Pg.3]    [Pg.319]    [Pg.19]    [Pg.102]    [Pg.190]    [Pg.193]    [Pg.201]    [Pg.95]    [Pg.3]    [Pg.4]    [Pg.23]    [Pg.13]    [Pg.3]    [Pg.319]    [Pg.19]    [Pg.102]    [Pg.190]    [Pg.193]    [Pg.201]    [Pg.434]    [Pg.478]    [Pg.36]    [Pg.83]    [Pg.91]    [Pg.85]    [Pg.21]    [Pg.345]    [Pg.9]    [Pg.4]    [Pg.55]    [Pg.254]    [Pg.163]    [Pg.19]    [Pg.141]    [Pg.242]    [Pg.111]    [Pg.238]    [Pg.392]    [Pg.463]    [Pg.128]    [Pg.417]    [Pg.10]   
See also in sourсe #XX -- [ Pg.190 , Pg.193 ]




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