| 摘要: | 近年因氣候異常使得台灣山坡地之安全監測重要程度逐年上升，但傳
統人力監測需耗費大量人力、機具、時間等成本，因此防災自動化監測技術逐漸普及，並隨著大數據、IoT(Internet of Things)概念而日益受到重視。時域反射技術(Time Domain Reflectometry，TDR)近期已被廣泛應用於土木監測，運用該技術可監測橋梁沖刷、水位、邊坡滑動及泥砂濃度等。近幾年隨著微控制板如 Arduino 與 MEMS（ Microelectromechanical Systems）微感測器所形成之物聯網概念下，在既有的 TDR 監測系統之外，輔以多點的淺層崩塌物聯網監測模組，預期可增加邊坡滑動監測的有效數據種類，例如以Ublox GPS 晶片透過 RTK（Real Time Kinematic）解算定位資料，可有效確認邊坡地表位移狀態；以及三軸加速度計具有即時得知地表的傾度感測資料的優點，結合既有 TDR 地下滑動面監測，於不同之時間與空間尺度下，
可完成三道重要的監測邊坡滑動的判斷機制。本系統並結合溫度計、溼度計、土壤濕度計等感測元件，最後藉由 LPWAN(Low-Power Wide-Area Network)無線傳輸技術回傳監測數據至服務端。
另外本研究基於 OGC(Open Geospatial Consortium)所制定之 SensorThings API 的 Web 服務協定標準，包含感測器、觀測位置、觀測時間與觀測屬性，可由 JSON (JavaScript Object Notation)及 REST(Representational State Transfer)協議描述，故可提供比先前 SOS(Sensor Observation Service)標準更輕量化、更自由化的標準定義，更符合物聯網系統輕量化資料傳輸的理念。因此本研究提出 SensorThings API與 TDR 監測資訊平台連結應用之架構規劃與實作，以資料完全自動化為導向，將 TDR 監測資訊平台中所有感測器的異質性資料加以管理與描述，藉以提昇 TDR 監測資訊系統之資料交流效率。;The automatic monitoring systems are gradually concerned for disaster prevention in Taiwan recently. Time Domain Reflectometry (TDR) is one of valuable technique for landslide monitoring. It is a passive-based monitoring method which provides multi-functions, such as water level, bridge scour, landslide, and suspended sediment concentration (SSC), based on a single TDR device via a multiplexer. In addition, the Real Time Kinematic (RTK) based single frequency GPS sensor can provide the centri-meter for the surface displacement and direction of the landslide. Thus, this study integrate the low-cost monitoring device with single frequency GPS three-axis accelerometer for surface displacement monitoring, as well as the TDR for sliding surface monitoring. Consequently, the proposed monitoring system not only can provide diverse monitoring data at field-side, but also have three thresholds for early waring of the landslide.
Furthermore, the Open Geospatial Consortium (OGC) provided SensorThings API, which has a standardized definition for the sensor description, observed position, and observed feature. Because it is based on JSON and Restful proctols, the content of SensorThings API is lighter and more liberal than Sensor Observation Service (SOS). Besides, it realizes data interoperable way by providing web service. This study also improved a middleware, which is between SOS and the existing TDR monitoring platform, by providing TDR heterogeneity data interoperability via SensorThings API finally. |
