以CSRS-PPP網際服務分析－六龜D015大規模崩塌潛勢區簡易觀測站數據品質

Quality Check of Kaohsiung Liugui Monitoring D015 Station GNSS Data with CSRS-PPP Internet Service

史天元 ； 王慧蓉 ； 廖志中

《地籍測量：中華民國地籍測量學會會刊》 38卷2期 (2019/06) Pp. 1-20

摘要

高雄市六龜區D015為林務局，依據光達微地形特徵所判釋出之大規模崩塌潛勢區之一。為進一步了解本區域之崩塌行為與發展，配合擬定管、治理策略，林務局屏東林區管理處於此區域設置簡易觀測站，以進行長期監測。本研究以加拿大CSRS-PPP網際服務，分析D015區域六個GNSS觀測站於2017年10月所蒐集之數據。本批數據相當不完整，僅一個測站在時間區間內每日均有檔案，可是該站多日均有次數、長短不一的斷訊。經整理除錯後，以CSRS-PPP網際服務進行分析。該項服務為單點精密定位，適合於處理零散、觀測時間不一之數據。本文以各測站觀測時間最長的日檔（Day File），探討該站儀器與環境之影響。由CSRS-PPP所提供之報表與資訊，可以了解各站同時具有儀器不穩定與環境不理想之問題。本文記述此一分析過程中的典型案例，以提供各界在有相同需求時分析處理之參考。監測站之觀測成果，如何與所欲監測、了解之物理性質對象相關，需要具備大地工程、地質等相關知識研判。本研究僅由觀測量本身求解，釐清這些觀測量所能求解坐標之不確定度。

並列摘要

D015, located in Liugui, Kaohsiung city, is a large-scale potential landslide site identified by the Soil and Water Conservation Bureau based on topography and geological conditions. In order to further understand the nature and development of landslides in the area, and facilitate an effective mitigation plan, the Ping-Tung Forestry Administration under the Bureau of Forestry established monitoring stations on the site. This study analyzed the data collected from six GNSS stations in D015 with Canadian CSRS-PPP Internet online service. This data, collected in October, 2017, is quite incomplete. Only one station has recorded observations over a period of 31 days, but the information was incomplete for each day. After removing format errors, the data finally were acceptable to CSRS-PPP service. The computation scheme of this service is Precise Point Positioning, and very suitable for fragmented files with frequently mismatched observation times. This paper documents the problems resulting from either instrumentation or environmental deviations/influence/factors as observed from the CSRS-PPP report. For evaluating the value of these monitoring stations in recording landslides, professional knowledge in geotech engineering and geology is necessary. The scope of this paper is limited to the quality of coordinates collected from these stations.