surveying iii (topographic and geodetic surveys) - Modern Prepper

least-square adjustment in a survey network allows for the computation of a single solution for eachstation and minimizes the corrections made to the field observations. A least-square adjustment usesprobability in determining the values for particular unknowns, independently weighs all fieldobservations, highlights large errors and blunders that were overlooked before adjustment, and generatesinformation for analysis after the adjustment (including estimates of the precision of its solutions).f. Traverses. Traverse is the measurement of lengths and the determination of directions of a seriesof lines between known points. They establish the coordinates of the intermediate points. Whencomputed, the accumulated closing error shows up as a position displacement of a known point. Thedisplacement is corrected and distributed among the intermediate (traverse) points.g. Elevations. Depending on the purpose, the elevations on some level lines are computed as themeasurements are taken. When the line is closed, the difference in elevation (DE) between the measuredand the known elevation is adjusted over all the stations in the line. In higher-order leveling, only thedifferences in elevation are recorded during the measuring, and all adjusting is done at the completion ofthe line. The error is then distributed among the various sections of the line.2-26. Establishing Records. Office computations reduce the field notes to a tabular or graphic form.They become a permanent record and are stored for further use or subsequent operations. Manystandardized forms are available and should be used. As long as the sheets are clearly identified andbound as a set, they are acceptable. Normally, all field notes should be abstracted and filed separately.The abstracts should be bound along with all computing forms into a single binder or folder andmaintained on file for further reference. All pages should have the name and date of the personperforming the work and at least one person who verified that page. Do not dispose of or destroy any ofthese records.2-27. Performing Checks. Surveying involves a series of checks. The observer, the recorder, and theparty chief should check the field notes before they are turned in for office work. Before computing, theassigned person should check the notes again. Most mathematical problems can be solved by more thanone method. When checking a set of computations, it may be desirable to use a method that differs fromthe original computation method. An inverse solution (starting with the computed values and solvingfor the field data) or a graphic solution may be used. Each step that cannot be checked by any othermeans must be checked by a totally independent recomputation by another individual. Any errors ormistakes that are found must be resolved and rechecked before the computation is accepted.2-15 EN0593