Aperiodic data

For both periodic cases and aperiodic data we may work with either continuous functions or sampled data. 

Typical magnetoconductance data for the individual MWCNT are shown in Fig. 4. At low temperature, reproducible aperiodic fluctuations appear in the magnetoconduclance. The positions of the peaks and the valleys with respect to magnetic field are temperature independent. In Fig. 5, we present the temperature dependence of the peak-to-peak amplitude of the conductance fluctuations for three selected peaks (see Fig. 4) as well as the rms amplitude of the fluctuations, rms[AG]. It may be seen that the fiuctuations have constant amplitudes at low temperature, which decrease slowly with increasing temperature following a weak power law at higher temperature. The turnover in the temperature dependence of the conductance fluctuations occurs at a critical temperature Tc = 0.3 K which, in contrast to the values discussed above, is independent of the magnetic field. This behaviour was found to be consistent with a quantum transport effect of universal character, the universal conductance fluctuations (UCF) [25,26]. UCFs were previously observed in mesoscopic weakly disordered... 

Figure 16.7 Seasonal and interannual variations in NOs concentrations at Station ALOHA. Shown are (A) the 16-year data set on NOs (nM) in the upper 200 m as well as the summer vs. winter climatologies. Note the log scale in both graphs. (B) integrated (0-100 m) inventories of NO3 showing aperiodic irgections of NO3 into the upper euphotic zone. Note the lower graph presents the data on a log scale to emphasize the extreme temporal variability in N03 inventory which exceeds a factor of300 over the 16-year observation period,...

The value of this response time analysis (RTA) is that is can be easily modified to accommodate a variety of application characteristics and platform constraints (Burns, 1994), including irregular release patterns, phased executions (i.e offsets), processes with multiple deadlines, processes with forward or backward error recovery, soft and firm deadlines, aperiodic processes, etc. The necessary mutual exclusive protection of shared state data is provided by priority ceiling protocols. 

The X-ray data obtained for fibers prepared from different B/N/P ratios showed variations in the positions and intensities of the maxima. Excellent agreement was obtained between the positions of these observed maxima and those predicted for an aperiodic array of points where each point represented a monomer in a random chain, separated from adjacent points by the appropriate monomer lengths. 

The most striking feature of the X-ray data is that there are several meridional maxima, and that these are not orders of a single repeat distance but are aperiodic and also vary in position depending on the monomer ratio. At present there is no information on the monomer sequence distribution from NMR analysis. (The polymer has... 

This chapter presents certain simple methods for describing mathematically some of the types of signals which are encountered in biomedical research. Techniques are described for both periodic and aperiodic signals. Techniques for extraction of signals from noise are also presented. Signal description and not data reduction is the theme of this chapter. For techniques directed toward statistical analysis of data, the reader is referred to standard reference works (for example, Wortham and Smith, 1959). 

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