The phrase "as a reference direction" is correct and usable in written English.
It can be used when indicating a specific direction or guideline that serves as a point of reference in a discussion or analysis.
Example: "In this experiment, we will use the north pole as a reference direction for our measurements."
Alternatives: "as a guiding direction" or "as a point of reference".
A polar coordinate system locates a point by its direction relative to a reference direction and its distance from a given point, also the origin.
The direction of the product is found by adding the angles that each of the two have been turned through relative to a reference direction: that gives the angle that the product is turned relative to the reference direction.
A reference direction may be the horizontal or vertical, or the x- or y-axis.
The scribe lines are drawn with respect to the wafer flat and the chip is cleaved along the scribed lines Fig. 8 Fabrication of channels using the cleaved-edge as the reference direction: a optical photograph of a cleaved edge on {110} wafer, b long channels (black portion) fabricated on Si{110} using cleaved edge as the reference direction, c a micrograph of the sidewall of fabricated channels.
The normal vector pointing to outside cast surface is considered as the reference direction for offsetting (Fig. 6a).
Vertebral rotation at a given level was estimated from surface rotation at the pertinent point of the symmetry line, with the sagittal direction as the reference direction.
The otolithic membrane and otoconia bend the hairs in the direction of gravity, providing the animal with a vertical reference direction; similar organs of balance, known as statocysts, are common in invertebrates.
The slowness values for P-, and surface, waves are used as a reference for estimating the direction of the tremor source.
For the sake of conciseness, we only cite below the three most important optimizations we carried out, whose savings are summarized in Table 2, where the more complex of the six designs (in terms of FPGA resources consumed) is used as a reference (VTV-Expressway Same Direction with Wall).
