## 5 Parameterisation Studies
### The Limits of Material Distribution Coefficient \"na\"
The \(T_{R}\) values of the system with the support bar consisting of \(c_{A}ratio>1\) material pairs at \(na\) = 100 are ranked according to [PERSON]'s modulus, except for the \(Al\)/\(Pb\)material pair (Figure 20, Table 8). The effect of the second material increases with increasing \(na\) in material pairs. 9. For the \(SS\) frequency parameters of the system with the _Ag/Pb_ and _Cu/Pb_ material pairs under the condition of \(c_{A}ratio<1\), the \(T_{R}\) values are maximum for \(na=0\), while the \(T_{R}\) values are minimum for \(na=100\). Although there are exceptional cases, the general trend is in this direction. In contrast to the other material pairs with \(c_{A}ratio<1\), for the \(SS\) frequency parameters of the system with the _Al/Pb_ material pair, the \(T_{R}\) values are maximum for \(na=100\), while the \(T_{R}\) values are minimum for \(na=0\) and the various \(na\) values (Table 6, Figure 20). 10. When \(c_{A}ratio>1\), for \(SS\) frequencies, minimum \(T_{R}\) values are realised for \(na=0\) and maximum \(T_{R}\) values for \(na=100\). The minimum and maximum values are shown in Tables 6 and 8 with different background colours (max: orange and min: green). 11. In the frequency responses of \(SS3\), \(SS4\) and \(SS5\), in the case of \(c_{A}ratio>1\), although the trend is for \(T_{R}\) to increase with increasing \(na\), the trend has minima at different \(na\) values. The minimum values of \(T_{R}\) are lower than the value of pure \(Pb\). In the case of \(c_{A}ratio<1\), except for the _Al/Pb_ material pair, the decreasing \(T_{R}\) trend continues after making minima at different \(na\) values. For \(SS4\) and \(SS5\) frequency responses, the minimum values of \(T_{R}\) are lower than the values of pure \(Pb\). For \(SS3\), \(SS4\) and \(SS5\) frequency parameters, the best isolation of the force transmission is achieved at different \(na\) values. The material pairs and \(na\) values that provide better isolation than the pure \(Pb\) bar system are as follows: * \(SS3\) frequency response: for \(Pb\)/_Al_, \(Pb\)/\(Br\) material pairs at \(na=1\) and \(Pb\)/_Cu_ at \(na=0.5\), the best isolation is achieved with \(Pb\)/_Br_ material at \(na=0.5\); * \(SS4\) frequency response: for \(Pb\)/_Al_, \(Pb\)/\(Br\) material pairs at \(na=0.2\) and \(Ag\)/\(Pb\) material at \(na=5\) and for \(Cu\)/\(Pb\) material at \(na=10\) with minimum transmission, the best isolation is achieved with \(Pb\)/_Al_ material pair at \(na=0.2\); * SS5 frequency response: with minimum transmission values of \(Pb\)/_Al_ at \(na=1\) and \(Cu\)/\(Pb\) at \(na=10\), the best isolation is achieved with the material pair \(Pb\)/_Al_, \(na=1\) (Figure 20 and Tables 6-8). 12. In the regions where the bar motion is dominant, _1.region_ and others, there is a minimum force transmission for \(na=0\) for the materials with \(c_{A}ratio>1\), while maximum \(T_{R}\) values occur for different values of \(na\). For the materials with \(c_{A}ratio<1\), there is a minimum force transmission for \(na=100\) except for the _Al/Pb_ material pair. There is a maximum force transmission for \(na=100\), while minimum \(T_{R}\) values occur for different values of \(na\) for the _Al/Pb_ material pair (Tables 6 and 8). 13. In _1. Region_, there is a trend for the transmissibility of the side frequency parameters. This distribution shows a trend according to \(na\) less than and greater than 1 for the other regions. For the material pairs with \(c_{A}ratio>1\) and _Al/Pb_ material (\(c_{A}ratio<1\)), \(T_{R}\) values increase with increasing \(na\). For the material pairs with \(c_{A}ratio<1\), the \(T_{R}\) values decrease with increasing \(na\) (Tables 6 and 8 and Figures 13-19). 14. The \(T_{R}\) values decrease as the frequency parameters increase for _1. Region_, _2. Region_ and _3. Region_ for \(na=100\) and \(c_{A}ratio<1\) (i.e., \(T_{R}\) values, _1. Region_: 5305, _2. Region_: 1681, _3. Region_: 919 for the _Al/Pb_ material pair at \(na=100\) in Table 6).