In addition to AKF, there is Transactional Auto Scaler (TAS), Scalability Patterns Language Map(SPLM) and Person Achieved Ubiquitous Manufacturing(PAUM)...
This pdf describes the assessment models (Quantitative/Qualitative) of scalability, in different areas such as: Manufacturing Systems, Computer Science, Organizational and Business.
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If the above models do not measure or at least help measure -I think-, please consider this researche
to measure the scalability which discusses several technics.
Scalability can be measured in various dimensions, such as:
Administrative scalability: The ability for an increasing number of organizations or users to easily share a single distributed system.
Functional scalability: The ability to enhance the system by adding new functionality at minimal effort.
Geographic scalability: The ability to maintain performance, usefulness, or usability regardless of expansion from concentration in a local area to a more distributed geographic pattern.
Load scalability, And so on..
AKF looks like a model not an approach to measure scalability, from the definition:
"The Scale Cube helps teams keep critical dimensions of system scale in mind when solutions are designed and when existing systems are being improved. "