E1C02 09/14/2010
13:35:23 Page 77
2.31 The file sunspot.txt contains data from monthly observations of sunspot activity from January 1746
to September 2005. The numbers are a relative measure of sunspot activity.
a. Using the companion software program Dataspect, plot the data and create an amplitude spectrum.
b. From the spectrum, identify any cycles present in the sunspot activity and determine the period(s).
c. The Dalton minimum describes a period of low sunspot activity lasting from about 1790 to 1830;
this is apparent in your plot of the data. The Dalton minimum occurred near the end of the Little
Ice Age and coincided with a period of lower-than-average global temperatures. Research the
‘‘year without a summer’’ and its relationship to the Dalton minimum.
2.32 Classify the following signals as completely as possible:
a. Clock face having hands.
b. Morse code.
L
L
Figure 2.26 Upward gas–liquid flow: slug flow regime.
Problems 77
13:35:23 Page 77
2.31 The file sunspot.txt contains data from monthly observations of sunspot activity from January 1746
to September 2005. The numbers are a relative measure of sunspot activity.
a. Using the companion software program Dataspect, plot the data and create an amplitude spectrum.
b. From the spectrum, identify any cycles present in the sunspot activity and determine the period(s).
c. The Dalton minimum describes a period of low sunspot activity lasting from about 1790 to 1830;
this is apparent in your plot of the data. The Dalton minimum occurred near the end of the Little
Ice Age and coincided with a period of lower-than-average global temperatures. Research the
‘‘year without a summer’’ and its relationship to the Dalton minimum.
2.32 Classify the following signals as completely as possible:
a. Clock face having hands.
b. Morse code.
L
L
Figure 2.26 Upward gas–liquid flow: slug flow regime.
Problems 77