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A Study of Rainfall Intensity and Changes from 1960 to 2004
No full text[[abstract]]近幾年來全球各地發生許多氣候異常的事件，台灣降雨情形在全球氣候變遷的影響之下，是如何影響降雨情形與變化。台灣島山區面積佔全島三分之一，當暴雨事件雨颱風事件時，經常會造成許多天然災害，如山崩、地滑與土石流等；影響集水區的水文情況，也影響下游水庫。
過去研究大多以中央氣象局的氣候測站資料來探討氣候變遷，包括氣溫、日照時數、降雨日數與降雨強度等參數來，探討低海拔氣候變化特徵，而未能探討到山區與高海拔各降雨參數的變化，本研究利用中央氣象局逐日局屬觀測資料20 個站與水利署的29 雨量站的資料，分析台灣年降雨量、最大日降雨量分析、年降雨日數、雨量大於50 ㎜日數、雨量大於50 ㎜日數比例、降雨強度，並利用時間序列回歸模型分析1960～2004 年來的變遷。
年平均雨量方面，以台北以及宜蘭的雨量最多，年雨量可達 3,000 ㎜以上，並沒有雨量隨海拔高度增加的趨勢，而中南部以及東部地區年降雨量在2,000 ㎜到3,000 ㎜之間，並且山區雨量較平地雨量多年雨量隨著海拔高度增加，並可以發現思源啞口為重要的氣候分界。最大日降雨量分布分面，發現山區的最大日降雨，平均最大日雨量集中在北部的陽明山、東半部的山區以及阿里山，平均約400 ㎜的單日降雨量，造成這些地區大量降雨主要是由於颱風事件所造成的。年降雨日數方面，年降雨日數分布大致由東北部向西南部遞減，最大為陽明山鞍部的209 日到最低的高雄106 日，差距將近兩倍，且山區高海拔的降雨量有較平地低海拔地區高的現象。依照中央氣象局的標準「當有連續降雨，而且24 小時雨量累積到130 毫米時，會發布豪雨特報；如果降雨量不到130 毫米，卻在50 毫米以上，且有可能造成災害時，便發布大雨特報。」因此，將日降雨大於50 ㎜日數進行統計分析，北部地區的大雨日數明顯高於其他地區，其他地區山區的大雨事件也較高；若統計大雨在年降雨日數所佔的比例，西南部地區有9％降雨日為大雨事件，並且隨著越北部，比例則越低，而至台北地區比例略升高為7％，如宜蘭南部山區大雨的日數比例約6％。
降雨強度方面，降雨強度參數則與雨量大於50 ㎜日數的分布相當類似，可以發現西南部地區的降雨強度約20 ㎜/day，而中部山區，如萬大一帶的降雨強度也明顯較高，而東北部山區與東南部地區降雨強度較弱，約15 ㎜/day。將1960-2004 年以來降雨資料利用時間序列回歸模型分析，得到各參數的變遷趨勢 (ß1 值)，在空間上的歧異大，並平地低海拔地區與山區高海拔之間沒有
明顯的不同。日最大降雨量變遷方面，北部東北部最大日降雨量大部分測站有下降的趨勢，僅在台東以及屏東出現增加的趨勢。降雨日數變遷方面，在空間分布上歧異度非常大，如從中央山脈的思源啞口往南到合歡啞口、雲海之間，日降雨量增加與減少交互出現，顯示受到影響的因子相當複雜，而在其他地區，大部分的測站降雨日數皆呈現下降的情形。日降雨量大於50 ㎜的日數方面，顯示大部分的測站大雨是間接有增加的現象，尤其以臺北測站最為明顯。日降雨強度變遷上，大部分的測站皆呈現增加的趨勢，僅有宜蘭縣的蘭陽溪中上游的測站大多呈現趨緩的趨勢。[[abstract]]Recently, there’re a lot of extreme climate events in the world. The main purpose of this study was to research rainfall intensity change in Taiwan. Many researches investigate rainfall change in plain region without investigating in mountain and alpine region..
The daily rainfall data was selected from 20 meteorological sites of Central Weather Bureau and 29 Rain Gauge sites of Water Resources Agency from 1960 to 2004 to analyze annual rainfall, maximum rainfall of single days, rainy days, the number of days > 50 ㎜ and rate, annual intensity of rainfall. There’re lager annual rainfall and rainy day in north-east Taiwan. In the other area, the lager annual rainfall and rainy day were increasing with elevation. the number of days > 50 ㎜ rate and annual intensity of rainfall were large in south-west Taiwan which were up to 9％ and 20 ㎜/day.
However, the pattern of rainfall change was complex and divergent. Most of the sites reveal increasing trend in rainfall intensity in Taiwan, excluding the rainfall intensity in LanYan river basin in 1960 to 2004
Magnitude-Frequency Distribution of Rainfall-Triggered Landslide Erosion in Kaoping River Watershed, Southern Taiwan
No full text[[abstract]]Magnitude-frequency of landslide erosion is a critical component to investigate the long-term erosion rate, landscape evolution, and natural hazard in tropical and mountainous area. In this study, the relationship between magnitude and temporal frequency for rainfall-triggered landslide erosion was been quantified in the Kaoping River watershed, southern Taiwan. The magnitude of landslide erosion was estimated by using multi-temporal landslide inventory with volume-area relations. The long-term frequency of landslide was derived from the record of 244 storms in 53 years and using hydrological frequency analysis by 6 types of probability distribution function. Then, we utilized the concept of an expectation of landslide erosion (EXLE) to explore the contributions of different rainfall intensity and to analysis the landslide erosion rate. The results show that the magnitude-frequency distributions show negative and piecewise power-law functions and the EXLE increase over the rainfall intensity. This reveals that landslide erosion triggered by intensive-extreme rainfall is more important than it triggered by moderate-frequent rainfall. Then, the landslide erosion rate is estimated to be 2.99 - 5.27 mm yr-1 in which rainfall with return period >= 10 years contributes 56-75% of total landslide erosion in the Kaoping River watershed. Analyzing the magnitude-frequency distribution is a reliable method that can quantify the contribution of landslide by different rainfall intensity and can avoid the uncertainty resulting from extreme event in estimation of landslide erosion rate
Dynamic Modeling of Sediment Production and Transport at Watershed Level
No full text[[abstract]]颱風豪雨引起山區大量土砂生產和搬運，經常直接危害人命與財產安全，也改變河床地形，威脅水利和水資源工程設施。為評估颱風豪雨造成的土砂生產和運移之動態變化，本研究整合崩塌潛勢模式、土砂生產模式與土砂運移模擬，建立一套集水區土砂生產和運移動態模式。首先，由水筒模式模擬降雨期間的土壤水指數變化，結合二元迴歸模式分析邊坡崩塌潛勢；再利用崩塌體積-面積經驗式，計算崩塌土砂量，以及通用公式計算土壤沖蝕量；最後，根據地表逕流和邊坡土砂生產量，模擬土砂受到逕流沖刷和土石流流動的運移現象。並以石門水庫集水區的白石子集水區為測試案例，結果顯示崩塌潛勢分析的成功率介於0.74~0.79，逕流量的效率係數為0.82，土砂入流量也有一定的合理性。而在極端降雨情境的模擬結果顯示，崩塌為集水區主要土砂來源，並造成2~5公尺的河床淤積。顯示本模式能夠應用於模擬山區集水區的土砂生產和運移之動態變化，提供下游水庫淤積和河防安全評估之依據。[[abstract]]Sediment production and transport triggered by typhoon precipitation are critical issues in Taiwan. These natural phenomena usually cause direct damages on the human's life and properties and change river bedform threaten the hydraulic and water resources facilities. To evaluate the dynamic of sediment production and transport triggered, an integrated model was developed which couples landslide susceptibility, sediment production from landslides and soil erosion, and sediment transport models. The model first used soil water index from tank model as a triggering factor of logistic regression to model the landslide susceptibility.
Second, sediment production from landslides was simulated based on the landslide susceptibility and an empirical relation of landslide volume-area, and the Universal Soil Loss Equation was used to calculate the soil erosion rate. Third, the sediment transports induced by the forces of water and gravity was simulated based on the runoff from tank model and Hunt's model. Then, the model was applied and tested in the Shihmen Reservoir watershed. The results show acceptable performances in predicting the landslide susceptibility (AUC = 0.74~0.79), runoff (coefficient of efficiency = 0.82), and sediment discharge. Under an extreme rainfall scenario, landslides are the major source of sediment resulting approximately 2~5 m of sediment accumulation occurred on the upstream. The test confirmed that the model is capable of modeling the dynamic of sediment production and transport at watershed level and providing the useful information for evaluating the sedimentation in reservoir and river
專利視覺化影片 推廣本校師長研發成果
No full text[[abstract]]本校科技研究總中心爭取科技部研發成果推廣活動計畫，由資管系吳佩芬老師與拍攝製作團隊，將本校師長創作之專利，以活潑、生動的影片及動畫，簡單明瞭的說明專利概念、優點與特色及未來應用。科技研究總中心並將完成的專利推廣影片，置於YouTube供大眾點閱，亦將YouTube網址（https://www.youtube.com/channel/UC-Z8DDt21FLRQnMBCOwLHjQ）以電子郵件方式轉知8百多家相關廠商知悉，積極尋找媒合廠商。
本項計畫是為解決空間、時間、金錢以及人力上的推廣問題，達成專利授權與技術移轉的目的，進而促進產學合作與交流，以落實促進知識產業化，並協助產業升級。希望藉由本計畫的支持，開啟校內專利及非專利技術影片的風氣，並找出經濟有效率的製作方式與利用模式，以持續製作與推廣。（科技研究總中心
「抗震保安，感動123」國立彰化師範大學101年國家防災日活動
No full text[[abstract]]為響應101年「國家防災日」活動，本校於9月21日實施「抗震保安，感動123」（一分鐘內所有參與者均完成地震避難掩護動作；進德、寶山兩校區全體師生一起動員參與；蹲下、掩護、穩住3個要領）地震避難掩護演練，藉此模擬實作強化校園師生災害防救、自救救人與應變能力，養成學生在地震發生時咸有正確的本能反應，維護生命安全。
學務處為提升防災成效，運用新生家長日、LED牆及學校網頁等多處管道進行地震避難相關資訊及影片宣導，並與相關單位針對地震避難掩護演練時間流程及因應作為事項進行協調及說明，以有效整合校內資源，辦理預演及正式演練等相關工作。
地震避難掩護預演活動分別於9月14日及20日實施，學務處全體同仁皆投入協助演練實施。本重點置於地震發生後一分鐘內之掩護作為及熟悉逃生路線。第二次活動時邀請彰化縣消防局第一大隊彰化東區分隊參與指導，針對921地震案例介紹地震的逃生要領及注意事項等，強化同學對災害防範的認知，演練中亦實施滅火器及消防栓操作、緩降機使用、煙霧體驗、CPR心肺復甦術操作訓練等實務課程。
9月21日當日狀況發佈時參與演練師生均能依要領就地掩護及逃生疏散，學務長並於教學大樓廣場提醒演練同學，藉此活動記取臺灣921大地震、日本311大地震災害經驗，在遇到天災時，能立即正確防護及充分自救，參與師生均表示獲益良多（學生事務處）