If you have only been sleeping on your side, the technician may come into the room at some point and ask you to try to sleep on your back. If you never sleep on your back or cannot sleep on your back you do not need to do this in the study. Should I drink alcohol on the night of the sleep study?
To calculate the cross sectional area (CSA) of a cable, you have to use a micrometer to verify its diameter, then divide the diameter by two to get the radius (r).With the ra â¦ dius we can calculate the CSA of the cable.    CSA = pi x r2 (Applicable to solid wires only).se the formula pi x r2 (3.14 x radius x radius) to get the cross sectional area. The formula works for all measurement units whether they are inches, millimeters, centimeters or others. An alternative is to use (pi x d^2)/4. (3.14x diameter x diameter divided by 4) You do not then need to divide the original diameter.
A cross-sectional study may be purely descriptive and used to assess the frequency and distribution of a particular disease in a defined population. For example a random sample of schools across London may be used to assess the burden or prevalence of asthma among 12-14 year olds. 1  Analytical. cross-sectional study should be representative of whole the population, if generalisations from the findings are to have any validity. For example a study of the prevalence of diabetes among women aged 40-60 years in Town A should comprise a random sample of all women aged 40-60 years in that town.