王如意2006-07-252018-06-292006-07-252018-06-2920042004-07-31http://ntur.lib.ntu.edu.tw//handle/246246/10763一般碎形河川網路生成之方法乃利用碎形生 成單元經遞迴疊代之方法繁衍合成，而面對台灣集 水區之特殊地文及水文條件下，此種僅以單純碎形 生成單元繁衍模擬之方式實不易反應出台灣不同 集水區內河川網路之高度變異特性，故本研究擬引 入即時隨機碎形生成(real time random fractal generation)之寬度函數(width function)，作為河川網 路結構之量化指標，並進一步研析河網結構之特性 及其對水文響應函數之影響。隨著颱洪時期降雨量 之增加，河川網路之生成並不屬於完全隨機，而應 歸類為受限於降雨特性變化之條件式隨機特性，亦 即於颱洪暴雨過程中各時段河網生成之隨機特性 乃具有時變性而顯示出各時段之河網型態有所差 異。故本研究擬以台灣地區之數值高程模式(DEM) 資料及地理資訊系統(GIS)軟體River Tools，設定不 同大小之面積門檻值，以擷取流域中各集水區不同 尺度之河川網路；繼而以基本河網型態之寬度函數 配合隨機碎形生成及加熱退火理論進行計畫集水 區之河網寬度函數即時隨機生成繁衍及模擬，最後 再套配以寬度函數為主軸之地貌型瞬時單位歷線 (width-function based geomorphologic instantaneous unit hydrograph, WF-GIUH)模式進行集水區之瞬時 單位歷線推估。本研究提供另一種集水區地形特性 之分析方式，進而繁衍並合成集水區之河川網路寬 度函數，希冀可提昇台灣坡地集水區單位歷線推估 之精確度，俾能提供集水區防洪規劃及水土保持研 析之參考應用。The synthetic river networks are often generated from the “recursive replacement algorithm.” The recursive process starts with an initiator, then it is substituted with the generator and subsequently each segment of the generator becomes an initiator, being substituted again. Such a single-generator generation algorithm, however, may not really reflect the natural river network of the basin due to the uniqueness of Taiwan’s geomorphologic and hydrologic conditions. With the above considerations in this study, the width function and multifractals theory are adopted to generate the fractal river networks which are more multiple and flexible. In this study, the heating or annealing theory and random fractal generation are proceeded to explore the suitable properties of the river network for a basin. The generalized equations for width function of random fractal river network are needed to induce by the real-time heating and annealing process of width function. Accordingly, the width-function based geomorphologic instantaneous unit hydrograph model (WF-GIUH model) can be built up. And various numerical experiments are carried out in order to explore the random processes in channel networks generation. The study is prospective with an aspect to the exploration of an appropriate random fractal generation algorithm, offers another specific method to evaluate the geomorphologic characteristics of the hillslope watersheds and be referable to the hydrological simulation for project watersheds.application/pdf282016 bytesapplication/pdfzh-TW國立臺灣大學生物環境系統工程學系暨研究所隨機碎形生成加熱退火理論寬度函數地貌型瞬時單位歷線Random fractal generationHeating and annealing theoryWidth functionGeomorphologic instantaneous unit hydrograph(GIUH)reporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/10763/1/922211E002038.pdf