| 1665 |  | (\omega _\alpha  t) - \frac{{g_\alpha  \dot x_\alpha  (0)}}{{\omega | 
| 1666 |  | _\alpha  }}\sin (\omega _\alpha  t)} } \right\}} | 
| 1667 |  | % | 
| 1668 | < | & = & \mbox{} - \frac{{\partial W(x)}}{{\partial x}} - \int_0^t | 
| 1668 | > | & = & - \frac{{\partial W(x)}}{{\partial x}} - \int_0^t | 
| 1669 |  | {\sum\limits_{\alpha  = 1}^N {\left( { - \frac{{g_\alpha ^2 | 
| 1670 |  | }}{{m_\alpha  \omega _\alpha ^2 }}} \right)\cos (\omega _\alpha | 
| 1671 |  | t)\dot x(t - \tau )d} \tau }  + \sum\limits_{\alpha  = 1}^N {\left\{ | 
| 1674 |  | \frac{{g_\alpha  \dot x_\alpha  (0)}}{{\omega _\alpha  }}\sin | 
| 1675 |  | (\omega _\alpha  t)} \right\}} | 
| 1676 |  | \end{eqnarray*} | 
| 1677 | – |  | 
| 1677 |  | Introducing a \emph{dynamic friction kernel} | 
| 1678 |  | \begin{equation} | 
| 1679 |  | \xi (t) = \sum\limits_{\alpha  = 1}^N {\left( { - \frac{{g_\alpha ^2 | 
| 2026 |  | Using Equations \ref{introEquation:definitionCR} and | 
| 2027 |  | \ref{introEquation:resistanceTensorTransformation}, one can locate | 
| 2028 |  | the position of center of resistance, | 
| 2030 | – | \[ | 
| 2031 | – | \left( \begin{array}{l} | 
| 2032 | – | x_{OR}  \\ | 
| 2033 | – | y_{OR}  \\ | 
| 2034 | – | z_{OR}  \\ | 
| 2035 | – | \end{array} \right) = \left( {\begin{array}{*{20}c} | 
| 2036 | – | {(\Xi _O^{rr} )_{yy}  + (\Xi _O^{rr} )_{zz} } & { - (\Xi _O^{rr} )_{xy} } & { - (\Xi _O^{rr} )_{xz} }  \\ | 
| 2037 | – | { - (\Xi _O^{rr} )_{xy} } & {(\Xi _O^{rr} )_{zz}  + (\Xi _O^{rr} )_{xx} } & { - (\Xi _O^{rr} )_{yz} }  \\ | 
| 2038 | – | { - (\Xi _O^{rr} )_{xz} } & { - (\Xi _O^{rr} )_{yz} } & {(\Xi _O^{rr} )_{xx}  + (\Xi _O^{rr} )_{yy} }  \\ | 
| 2039 | – | \end{array}} \right)^{ - 1} \left( \begin{array}{l} | 
| 2040 | – | (\Xi _O^{tr} )_{yz}  - (\Xi _O^{tr} )_{zy}  \\ | 
| 2041 | – | (\Xi _O^{tr} )_{zx}  - (\Xi _O^{tr} )_{xz}  \\ | 
| 2042 | – | (\Xi _O^{tr} )_{xy}  - (\Xi _O^{tr} )_{yx}  \\ | 
| 2043 | – | \end{array} \right). | 
| 2044 | – | \] | 
| 2045 | – |  | 
| 2046 | – |  | 
| 2029 |  | \begin{eqnarray*} | 
| 2030 |  | \left( \begin{array}{l} | 
| 2031 |  | x_{OR}  \\ |