Smoothing running mean

Figure 13.11 is one example of variations in total column ozone in Europe, Eastern Siberia and the Far East, and Western Siberia (Bojkov et al., 1994). These data have been smoothed using a 12-month running mean, but variations due to the QBO etc. have not been removed. Figure 13.11c shows for the Western Siberia data the deviations specifically attributed to the QBO while this contributes to a significant extent to the observed trends, it clearly does not account for the entire downward trend in total ozone with time. 

FIGURE 13.11 Percentage variations in total column ozone smoothed using a 12-month running mean for a network of stations in (a) Europe, (b) Eastern Siberia and the Far East, and (c) Western Siberia from 1973 to March 1994. The arrows show the expected QBO. In (c) the dashed line shows the component that has a periodicity expected for the QBO (adapted from Bojkov et at., 1994). 

Figure 9.13. Global temperature change. The spikey curve is the annual mean temperature the smooth curve is the five-year running mean. Since the mid-1960 s, there has been a trend of increasing temperature of about 0.08°C/10 years. (After Hansen and Lebedeff, 1987.)...

Fig. 5. Global deep-sea oxygen isotope record after Zachos et at (2001). Curve represents the smoothed five-point running mean of data compiled from more than 40 DSDP and OOP sites. Vertical bars depict a rough estimation of ice volume in each hemisphere relative to the LGM. Dashed bar denotes periods of minimal ice coverage (<50%) full bar represents close to maximum ice coverage (>50% of present).

FIGURE 22.4 CO2 mixing ratio over the past 1000 years from the recent ice core record and (since 1958) from the Mauna Loa measurement site. The inset shows the period from 1850 in more detail, including CO2 emissions from fossil fuel. Data sources are given in IPCC (1995). The smooth curve is based on a 100-year running mean. All ice core measurements were taken in Antarctica. 

The dAc/dz term is usually zero since tubular reactors with constant diameter are by far the most important application of Equation (3.7). For the exceptional case, we suppose that Afz) is known, say from the design drawings of the reactor. It must be a smooth (meaning differentiable) and slowly varying function of z or else the assumption of piston flow will run into hydrodynamic as well as mathematical difficulties. Abrupt changes in A. will create secondary flows that invalidate the assumptions of piston flow. 

In the development of a refractory brick many questions play an important part, such as Is the brick able to withstand the chemicals it will come into contact with and How temperature resistant is the brick In the aluminium production described above bricks come into contact with liquid aluminium at high temperatures. By means of the aluminium cup test you can determine whether or not this contact runs smoothly. A cylindrical cavity is drilled into the brick and filled with liquid aluminium. Next both components are allowed to interact. As you can see in the photographs the material in question is not suitable. The phase rule is an excellent aid in answering the second question, as can be concluded from the phase diagram of the system Si02 / A1203 in figure 11.3.3)... 

Fumed silica aggregates are obviously linear and branched particle structures with a mean size of about 100 to 200 nm. By TEM we derive the size of the partially fused primary particles of about 10 run. This very small particle size correlates well with the high surfaces area of fumed silica which usually is larger than 100 m g as determined by nitrogen adsorption at 78 K according to BET [5]. Adsorption techniques and electron microscopy provide very close values of surface areas. This indicates that fumed silica exhibits a smooth particle surface in the range of nanometers, apparently its surface is free of micropores. 

Where a film has been well prepared and burnished to a high degree of consolidation and reflectivity, and is run against a similar film on the counterface, sliding will take place almost entirely between the smooth surfaces. Under those circumstances the wear rate will be extremely low, and may for a period even be nil, so that the mean film thickness remains unchanged for the remainder of the film... 

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