基本流量資料蒐集對於水資源規劃及管理為必要且重要的依據,尤其是對於暴雨造成的中、高流量而言。一般傳統的流量量測法耗力且費時,對於暴雨時期河川水位隨降雨而迅速漲落,因而造成較大的量測困難,且工作環境的惡劣更增加其危險性。因此應用費時較短且較簡便的高效率流量量測法來量測暴雨時期的中、高流量,以提高量測效率並減低危險性。然而流量的量測因為自然界種種不可避免的潛在因素及人為操作的不當,本身就具有不確定性的存在。本研究主要就是利用蒙地卡羅法對於高效率流量量測法、流速面積法及率定曲線法進行不確定分析,且利用不確定分析之結果來證明此法的可行性及可靠度,並比較應用高效率流量量測法量測之流量資料與流速面積法之流量資料之誤差值,建立高效率流量量測法的誤差信賴區間及利用相關係數來進行準確度分析。根據不確定分析結果顯示,就變異係數而言,高效率流量量測法之不確定性與具有較高可信度之流速面積法相近且其值低於率定曲線法,由此即可驗證高效率流量量測法應用於中、高流量之可行性及可靠度,並利用誤差分析建立出高效率流量量測法之誤差信賴區間為-18.6%〜18.9%,率定曲線法之誤差信賴區間為-30.0%〜30.5%,而高效率流量量測法準確度分析之相關係數為0.993。
The basic data of discharge collection is necessary and important for the management and planning of water resources, especially for middle-flow or high-flow heavy rains caused by heavy rains. The traditional methods of discharge measurement are time-consuming and labor-intensive, it is difficult to measure discharge during the period of heavy rains, because stage of the river rise and fall rapidly, and it is more dangerous to work in the worst situation. Therefore, using the Efficient Method of Discharge Measurement to measure discharge caused by heavy rains is more efficient, and it also reduce the risk. However, measurement exist uncertainty itself, because of variety of potential natural elements and man-made factors of improper operation. The purpose of this study is to use Monte Carlo simulation to the efficient flow measurement method, velocity-area method and the rating curve method for uncertainty analysis, and use the results of uncertainty analysis to prove the feasibility and reliability of the efficient method of discharge measurement. Then compare the error of discharge between the efficient method of discharge measurement and velocity-area method to establish of the error confidence interval of the efficient method of discharge measurement and use correlation coefficient to analysis accuracy. According to the results of the uncertainty analysis, as coefficient of variation as concerned, the value of the efficient of discharge measurement is less than rating curve method and close to velocity-area method, so that we can prove the feasibility and reliability of the efficient method of discharge measurement using on measurement of middle-flow or high-flow. At summary, the 95% error confidence level of the efficient method of discharge measurement is between -18.6%〜18.9% and the 95% error confidence level of rating curve is between -30.0%〜30.5%. The correlation coefficient of the efficient method of discharge is up to 0.993.