In the case of determination of a ship's position on the ocean, combinations of Loran lines of position or astronomical position lines are generally used. Hereupon, in the case of discussion about the comparative merits of these methods, it is very difficult to fix accuracies of these position lines to certain values, accordingly we can not get universal conclusions. The author discussed on this subject based on the understanding that the standard deviation (σ) of an astronomical position line equals 0.75, σ of transfer-red position line is expressed by 0.75 √t (t: sailing hours)and σ of measurement of time difference by Loran-C is dealt with 0.75, 1.5, 3.0 μ.s.
抄録全体を表示