Randomized Controlled Studies: This is a study in which 1) There are two groups, one treatment group and one control group. The treatment group receives the treatment under investigation, and the control group receives either no treatment (placebo) or standard treatment. 2) Patients are randomly assigned to all groups.
winds that blow in a steady direction can move a dune. such wind will consistently pick up sand from one side and deposit it to a other side. this causes the entire dune to s â¦ lowly move in the direction if the wind.
Waves that hit the beach at an angle carry sand and gravel up the beach face at an angle. When the water washes back the sediment is carried straight back down the beach face. Individual particles are moved along the beach in a zig zag pattern. This is called longshore drift.