Page 43 - IJB-6-4

Celik, et al.
where x represents the functions value
Feature cost* 9.22 6.8 3.3 - 7.95 32.48 1 100 weighting;
i
y represents functions cost weighting;
i

0.12315 a xy represents the regression parameter.
ii
F10 12.315 x i 2
0.8
1.2
0.5
0.5
1
4
The estimator S is determined with the
F9 0.75 0.3 0.2 0.7 0.75 2.7 0.08312 8.312 • smallest squares method:
i
F8 1 0.54 - 0.46 1 3 0.09236 9.236 S y ax g i 2 min� (3)
• The dispersion S’ must be as close as possible

F7 0.72 0.4 0.2 0.4 0.8 2.52 0.07758 7.758 to zero value to validate the solution.
S 2gg i 2 x y (4)
a x 2g
'
i i
F6 0.53 0.46 - 0.41 0.5 1.9 0.05849 5.849 • The angle  of the regression line:

F5 1.1 - 1.6 0.3 0.3 3.3 0.1016 10.16 α = arctg ( ) a 180 (5)
π
Table 3. Functions costs distribution matrix for redesigning a face shield.
All computational elements used in the smallest
F4 1.92 1 0.6 - 1.6 5.12 0.15763 15.763 squares method are presented in Table 4.
After processing, the information in Table 4,
F3 - 1.74 - 1.74 1 4.48 0.13793 13.793 the following values were obtained: a = 1.0021,
α = 45.05998, S = 31.886, and S’ = 0.
In Figure 4, Diagram A shows the functions
F2 1 0.56 - 0.2 0.5 2.26 0.06958 6.958 t for the redesign process of a face shield. The
diagram was constructed using the rankings
0.09852 9.852 of the functions by their value, as obtained in
0.5
0.5
3.2
0.2
F1 the valuation matrix. Diagram B represents the
1
1
ranking of the functions by their functional
cost, as defined in the cost distribution matrix.
Both diagrams are used by the TFA team to
compare the functions costs in relation to their
Main constructing features Main body frame Coronal plane positioning system Shield orientation and fixing system Lateral gripping features Forehead stabilizing rest important for the redesign process to identify
contribution to the value of the product. It is
the most expensive functions and those with
the highest weighting in the total cost of the
product. This way, secondary functions that
are very expensive in relation to the objective
functions, or even more expensive than these,

Total cost Cost of functions (%) can be identified for further improvement. The
weighting of effort for a certain function must
match its weighting in the total value of the
No. 1. 2. 3. 4. 5. Ratio product. Further, to validate these assumptions,

International Journal of Bioprinting (2020)–Volume 6, Issue 4 39