# New Landslide Disaster Monitoring System: Case Study of Pingding Village
## 4 Discussion
The fourth type of movement suffers from potential hazards in terms of the stability of side slopes if there is a certain trend in the displacement direction, because the displacement speed of this type of potentially moving side slope is extremely low--i.e., 0.5-2.0 mm every month, thus producing a displacement quantity of 6-24 mm every year. Further measurements are needed to confirm the stability of side slopes with displacement speeds of over 0.5 mm/month but without certain cumulative displacement directions (forward displacements and backward displacements have both been observed). The stability of such side slopes can be affected by measurement errors of devices or by the non-compact surrounding stuffing of inclination observation tubes when installed. The relevant precaution solutions and management principles provided by the Japanese Society for Expressways [46] are displayed in Table 3.  
To date, no domestic regulations have been set for relevant management values; in addition, no long-term monitoring results have been gained. Consequently, referring to Japan's recommended values and the device-measurable precision of side slope stability, judgement is inevitable, since Japan already has a certain amount of related experience. The retractable meters' action values are 5-10 times that of the vigilance values. The tentative monitoring management values are shown in Table 4 based on the premise that all of the monitoring devices' action values are five times that of their vigilance values. In the future, the data obtained by the monitoring of the devices will be analyzed, interpreted, and judged, and interactive comparisons will be made between different monitoring devices. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Movement Types**} & **Daily Movement (mm)** & **Monthly Movement (mm)** & **Accumulative Inclination of Certain Directions** & **Activity Judgement** & **Abstract** \\ \hline Emergency movements & Over 20 mm & Over 500 mm & Significantly apparent & Rapid mass wasting & Mass wasting movements and mudslides \\ \hline Definite movements (movement values) & Over 1 & Over 10 & Apparent & Moving actively & \
\begin{tabular}{c} Colluvial soil slips and deep slips \\ \end{tabular} \\ \hline Semi-definite movements (vigilance values) & Over 0.1 & Over 2.0 & Slightly apparent & Moving slowly & Clay slips and backfill slips \\ \hline Potential movements (alarm values) & Over 0.02 & Over 0.5 & Small &
\begin{tabular}{c} Further observation \\ is needed \\ \end{tabular} & Clay slips and deep slips \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Table of displacement speed and side slope stability judgment and suggestions [45]. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Monitoring Methods**} & \multicolumn{3}{c}{**Management Classification**} \\ \cline{2-4}  & **Attention** & **Vigilance** & **Evacuation Required** \\ \hline Land surface retractable meters & & \textgreater{}10 mm/day & \textgreater{}50 mm/day \\ Rainfall intensity & 0.5–10 mm/day & 10–20 mm/h & \textgreater{}20 mm/h \\ Cumulative rainfall & & 50 mm & 100 mm \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Monitoring management benchmarks of stratum slips [46]. In this study, by using these sensors, we integrated software and hardware to monitor landslides in Pingding. We aimed to review the benchmarking management values and to further investigate the management values. In addition, improvement of the real-time monitoring system was also expected after amending the management values based on different viewpoints to better determine the effects and efficiency of monitoring and vigilance. In Pingding, Taiwan, particularly in summer (i.e., the rainy season), rainfall is the main contributing factor to the occurrence of landslides, rockfalls, and mudflows. Rainfall information is mainly used to monitor whether there is rain alert on the spot. Station rain gauges, automatically adopt the rain station's operation method, and provide a self-sufficient method.