Mixed methods research takes advantage of using multiple ways to explore a research problem. The simple answer is triangulation in research methodology pdf overcome the limitations of a single design.
His framework involves four decisions to consider and six strategies. Characterized by: Collection and analysis of quantitative data followed by a collection and analysis of qualitative data. Characterized by: An initial phase of qualitative data collection and analysis followed by a phase of quantitative data collection and analysis. Characterized by: Collection and analysis of either quantitative or qualitative data first. The results are integrated in the interpretation phase.
Characterized by: Two or more methods used to confirm, cross-validate, or corroborate findings within a study. Purpose: The purpose of the nested method is to address a different question than the dominant or to seek information from different levels. Characterized by: The use of a theoretical perspective reflected in the purpose or research questions of the study to guide all methodological choices. This resource was created by Dr. University of Missouri – St. Collected 3D data is useful for a wide variety of applications.
If colour information is collected at each point, then the colours on the surface of the subject can also be determined. 3D scanners share several traits with cameras. 3D scanner collects distance information about surfaces within its field of view. The “picture” produced by a 3D scanner describes the distance to a surface at each point in the picture. This allows the three dimensional position of each point in the picture to be identified.
For most situations, a single scan will not produce a complete model of the subject. Multiple scans, even hundreds, from many different directions are usually required to obtain information about all sides of the subject. This whole process, going from the single range map to the whole model, is usually known as the 3D scanning pipeline. There are a variety of technologies for digitally acquiring the shape of a 3D object. Non-contact solutions can be further divided into two main categories, active and passive.
There are a variety of technologies that fall under each of these categories. A coordinate measuring machine with rigid perpendicular arms. A carriage system with rigid arms held tightly in perpendicular relationship and each axis gliding along a track. Such systems work best with flat profile shapes or simple convex curved surfaces. An articulated arm with rigid bones and high precision angular sensors. The location of the end of the arm involves complex math calculating the wrist rotation angle and hinge angle of each joint. This is ideal for probing into crevasses and interior spaces with a small mouth opening.
A combination of both methods may be used, such as an articulated arm suspended from a traveling carriage, for mapping large objects with interior cavities or overlapping surfaces. It is used mostly in manufacturing and can be very precise. The disadvantage of CMMs though, is that it requires contact with the object being scanned. Thus, the act of scanning the object might modify or damage it. This fact is very significant when scanning delicate or valuable objects such as historical artifacts. The other disadvantage of CMMs is that they are relatively slow compared to the other scanning methods.