## 2 Overview of Supplementary Damping Systems
### Classification of Damping Devices
#### 2.1.3 Classification by Functional Characteristics  
The classification according to the activation method, as shown in Figure 3, illustrates the transition from straightforward passive systems to more elaborate active and hybrid solutions. Passive systems, which operate independently of an external power source, are characterized by their reliability and low maintenance requirements, yet they are unable to respond to changing circumstances. Conversely, active systems deliver enhanced control and adaptability but demand intricate control systems, sensors, and external power sources, which increases their complexity and potential vulnerability to power disruptions.  
Hysteretic systems: These systems dissipate energy through cyclic stress-strain behavior. Examples include metallic yield dampers and friction dampers. The analysis of functional characteristics offers valuable insights into the fundamental physical principles governing energy dissipation. Hysteretic systems, such as metallic yield and friction dampers, dissipate energy through cyclic loading paths that generate distinct hysteresis loops. The area enclosed within these loops quantifies the energy dissipated during each cycle.  
Viscoelastic systems: These systems exhibit both viscous and elastic behavior. Examples include viscoelastic dampers and fluid viscous dampers. Viscoelastic systems integrate an instantaneous elastic response with a time-dependent viscous behavior. This integration facilitates efficient energy dissipation over a broad-frequency spectrum and proves particularly beneficial in mitigating vibrations caused by seismic activity and wind forces.  
Impact systems: These systems dissipate energy through controlled collisions. Examples include impact dampers and particle dampers. Impact systems and mass effect systems are two separate methodologies employed in vibration control. Impact systems function by utilizing controlled collisions to dissipate energy, whereas mass effect systems modify the dynamic properties of a structure by incorporating precisely calibrated auxiliary masses. These systems use additional mass to alter the dynamic characteristics of the structure. Examples include tuned mass dampers and tuned liquid dampers.  
Integration and Performance Considerations  
The characteristics illustrated in Figure 3 highlight the relationship among these various classification systems. For instance, a hybrid system could merge passive viscoelastic dampers with semi-active magnetorheological (MR) dampers, thereby ensuring a strong baseline performance while providing additional adaptable damping as necessary. This combination of diverse damping techniques and activation strategies enables engineers to devise tailored solutions that meet specific structural needs. The aforementioned characteristics of supplementary damping systems appear in Figure 3, as well as in Table 1.  
\begin{table}
\begin{tabular}{p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt} p{42.7 pt}} \hline \hline
**Damper Type** & \begin{tabular}{c} **Energy** \\ **Dissipation** \\ **Mechanism** \\ \end{tabular} & **Key Characteristics** & \begin{tabular}{c} **Primary** \\ **Applications** \\ \end{tabular} & **Advantages** & **Limitations** & \begin{tabular}{c} **Detailed** \\ **Discussion** \\ \end{tabular} \\ \hline Viscous & \
\begin{tabular}{c} Velocity- \\ dependent fluid \\ flow \\ \end{tabular} &
\begin{tabular}{c} \(\bullet\) \\ \(  
Furthermore, Table 1 presents a comparative analysis of supplementary damping systems.