中文摘要 台灣形狀南北長、東西窄,呈現狹長型,地形中間高,二側低,類似一個湯匙的背面,所以台灣河川皆呈現川短流急的狀況,地處亞熱帶季風氣候,夏天經常有颱風侵襲,在這個先天不良(地形)又後天失調(亞熱帶季風氣候)的情況下,夏天豐沛的水量自山上急衝而下往往造成主流河道的變遷並且沖刷著兩岸的堤防、護欄,及河上結構物的基礎,嚴重危害到兩岸居民及橋上用路人的生命財產安全,故研究預測主流河道的變遷情形便顯得相當重要。 本研究目的是以資料群集處理技術(GMDH)及適應性網路架構模糊推論系統(ANFIS)預測主流河道之變遷預測。經由現地資料調查與蒐集後可知,影響主流河道變遷的影響因子為入流位置、入流角度、坡度、流量、含砂量等。將各斷面之因子變化結合主流河道歷史變遷紀錄經由資料群集處理技術層層的競爭、演進產生出主流河道變遷方程式,用以預測超出歷史訓練資料的主流河道變遷趨勢;而歷史訓練資料範圍內的因子變量,則經由適應性網路架構模糊推論系統建立起的主流河道變遷模糊規則庫,經由模糊推論便預測不超過歷史資料之主流變遷情形。所以二者相輔相成,便能呈現出河道變遷的情形,可作為未來河上結構物建立及治理大甲溪下游流域之參考。
Abstract The narrow and long type of north and south appears in the form of Taiwan. The topography is similar to the back of a soup spoon. So rivers in Taiwan are all short and small and the velocity of flow is fast. Taiwan is the subtropics monsoon climate. There are typhoon attacks in summer often. So the massive water flushes from mountain. It often causes stream-way transition then assaults dike and bulkhead on two sides of river and foundation of the structures on the river that endanger the life of the residents of two sides and the passerby's life on the bridge seriously. So predict that stream-way transition is quite important. The purpose of this research is to predict stream-way transition with group method data handling (GMDH) and adaptive network-based fuzzy inference system (ANFIS).They are forecasting the downstream stream-way transition according to the upstream conditions by group method data handling and adaptive network-based fuzzy inference system. Five main factors about the stream-way transition are inflow position, inflow angle, slope, flow discharge, and sand content of suspended sediment. Use all factor data of every section and historical data then build stream-way transition equation by GMDH. This equation can be used for predicting stream-way transition that inputs go beyond the historical data; if the inputs are in the historical data range then sets up fuzzy rule-base. And then predict stream-way transition by fuzzy inference rules. We can present stream-way transition intactly via these 2 kinds of methods. I hope it is helpful to security of the structures on the river and administrate the downstream in Dajia River in the future.