Reverse thinking method

Another widely used predictive method is the use of Fault Tree Analysis. This is a reverse-thinking method. The analyst assumes an accident or specific undesirable event—the so-called TOP Event. This could be the release of a toxic gas from a reactor safety relief valve. 

ETA breaks down an accident iato its contributing equipment failures and human errors (70). The method therefore is a reverse-thinking technique, ie, the analyst begias with an accident or undesirable event that is to be avoided and identifies the immediate cause of that event. Each of the immediate causes is examined ia turn until the analyst has identified the basic causes of each event. The fault tree is a diagram that displays the logical iaterrelationships between these basic causes and the accident. 

Reverse Imaging. In imaging, one normally thinks of obtaining information about a system that is spatially and/or temporally resolved. However, similar approaches can also be used to project patterned information into a chemical system. This, for lack of a better phrase, is referred to as reverse imaging in this document. The idea is to use the same kinds of methods and machines that we use to record images to also control chemistry or biochemistry in a patterned fashion. 

The viscosity of a solution of a given polymer will be dependent upon the concentration of the polymer in that solution. Viscosity depends also upon molar mass. Higher molar mass means greater chain entanglement and therefore higher viscosity. Thinking about this in reverse, we can use viscosity as a method to determine the molar mass of a polymer sample. 

One continuation method reconstructs exactly the Newton method when t moves in the positive direction. Think of the surface that corresponds to summing the squares of the functions one wishes to drive to zero. If the Newton method flounders in a local hole in this surface where the bottom of the hole does not reach down to zero, and thus where the equations do not have a solution, it would be very useful to climb out of the hole by going in the reverse of the Newton direction (i.e., by simply reversing the sign on f), hopefully over the top of a nearby ridge and down the other side into a hole where a solution does exist. A continuation method does just this. 

Anyhow, the fact that mass patterns for DSa and DSs look so different prompt us to think that the two DISPIRO derivatives of S prepared by direct and reverse method respectively are not the same. 

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