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An expanded view

Figure 6 shows a greatly expanded view of the red average values in Figure 5 .

Figure 6. Expanded average value of a time series.
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The ideal value for this average is 0.5, and that is the value represented by the blue line. The plot in Figure 6 shows the same horizontal scale as Figure 5 . However, the entire vertical plotting area in Figure 6 represents the values from 0.48 to 0.52.

Ideal value is never reached

As you can see, the ideal value is never reached in Figure 6 except at isolated points where the red curve crosses the horizontal line. Even if Iextended the horizontal axis to 1200 or more points, that would continue to be the case.

A more serious case

Figure 7 computes and displays the average value of the bottom plot in Figure 2 (recall that this plot shows 1200 points on the horizontal axis, whereas Figure 5 shows only 400 points on the horizontal axis). Recall also that this time series was produced by multiplying two sinusoids having nearly thesame but not exactly the same frequency.

Figure 7. Computed average value of a time series.
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Red curve is the average

As before, the black curve in Figure 7 shows the time series, and the red curve shows the computed average value as a function of the number of pointsincluded in the average.

(In this case, I didn't even bother to show the short axis containing only 400 points. The horizontal axis in Figure 7 contains 1200 points, the same as in Figure 2 .)

The ideal average value is zero

In this case, the ideal average value is zero, as indicated by the green horizontal axis. As you can see, even for a 1200-point averaging window, theaverage value deviates significantly from the ideal. We will see the detrimental impact of this problem later when I perform spectral analysis in an attempt toseparate two closely-spaced peaks in the frequency spectrum.

Some additional examples of average values

Figure 8 computes and displays the average value of the third plot down from the top in Figure 3 . This plot was produced by multiplying the two sinusoids in the top two plots in Figure 3 .

Figure 8. Computed average value of a time series.
missing image

As before, the black curve in Figure 8 represents the time series, and the red curve represents the computed average value of the time series as a functionof the number of points included in the average.

For this case also, the ideal average value is zero, as represented by the green horizontal axis. The positive and negative peaks in the red average valuecan be seen to approach the ideal value asymptotically within the 400 horizontal points plotted in Figure 8 .

Figure 9 computes and displays the average value of the bottom plot in Figure 3 . This time series was produced by multiplying the top plot in Figure 3 by the fourth plot in Figure 3 .

Figure 9. Computed average value of a time series.
missing image

Once again, the black curve in Figure 9 represents the time series, and the red curve represents the computed average value of the time series as a functionof the number of points included in the average. In this case, the average converges on zero rather nicely within the 400 points included on the horizontalaxis.

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Digital signal processing - dsp. OpenStax CNX. Jan 06, 2016 Download for free at https://legacy.cnx.org/content/col11642/1.38
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