ENGLISH

15卷/1期

15卷/1期

華藝線上圖書館

Pages:

防災專刊

論文名稱

Guest editor's preface to the special issue on Natural Hazards

Title

作者

劉進金,徐百輝

Author

中文摘要

天然災害(Natural Hazards)的防救工作若是可為而不為,則看似天災,實為人禍。近年來因為全球變遷及暖化問題日漸加劇,造成全球的環境體系變弱,環境風險因而擴大,如何降低天災所造成的損失已成為人類永續發展的核心議題。地球觀測科技(Earth Observation Technology)進展的首要目的就是發揮其在防災、減災、抗災與避災等應用之社會效益。台灣因為地質破碎脆弱、地形陡峭、颱風豪雨與地震頻仍,環境與地形變動極為劇烈,天然災害的發生已是常態,所以必須採取長期可靠的防救措施。重大天然災害具有很強的因果災害鏈,防災與減災之效益遠大於救災,但是一旦災害發生,若不及時有效處理,很容易產生二次災害,以及衍生社會與經濟方面的問題,甚至於衍生政治問題。  臺灣近年來發生的重大天然災害包括賀伯颱災(1996)、集集大地震(1999)、桃芝颱風(2001)、納莉颱風(2001)、敏督利颱風(2004)與七二水災(2004)、卡玫基(2008)、以及八八水災(2009)等,航測及遙測技術已被廣泛應用在這些災害的防救工作以及學術研究上,中國四川大地震(2008)也廣泛應用最新的航測及遙測技術。緣此,航測及遙測學刊乃選擇天然災害防救為本期專刊之主題,彙整相關調查研究成果,以反映天然災害觀測、分析評估、預測、預防、與預警上的進展,作為防救災相關工作之參考。  本期專刊共收錄九篇論文,可以反應航測及遙測技術幾個主要的面向。這些應用有關的事件包括集集及汶川等地震災害,賀伯、桃芝、敏督利、莫拉克等颱風災害、以及七二水災、八八水災等災害事件。從資料面而言,各研究廣泛地應用多時期福衛2號(FS-2)及SPOT系列等衛星影像、航攝數位影像、空載及地面光達資料等,並輔以數值地形資料(Digital Terrain Models, DTM)及其他空間資料等,搭配地理資訊系統(GIS)為分析工具,以進行災害的辨認或災害地圖的製作。就技術面而言,張崑宗等人利用高解析衛星影像與地形資料所衍生之空間特徵,以提升衛星影像自動化暴雨型崩塌地之判釋精度。劉治中等人結合彩色航照與空載光達資料,藉由半自動化方式辨識崩塌地,並利用三維立體展示的人機操作介面,供人工判釋及編輯崩塌地邊界向量資料及屬性資料,提供後續之規劃參考用。黃韋凱等則利用物件導向式(Object Oriented)分析方法進行大範圍坡地與河川災害快速判釋,以改善像元式影像分析方法於分類時常有之雜訊問題。從應用面而言,葉堃生等提到關於緊急應變時,農林航空測量所如何進行數位影像的快速獲取、判釋分析及資訊分享,以提供各防救災相關單位在災害發生後能迅速掌握災害及災情資訊,為救災、減災以及災後重建提供了重要依據;尹孝元等說明過去農委會水保局如何利用遙測科技進行國土變異監測,包括山坡地變異點分析、崩塌地監測、地變形監測、及歷年海岸線變遷等應用。蕭國鑫等人利用地面三維雷射掃描儀,針對颱風前後河道地區進行三維雷射掃描,除製作高解析的高程地形外,並量化颱風前、後之崩塌土石變化。董家鈞等人則利用衛星影像進行堰塞湖判釋,並結合數值地形模型資料,配合可快速進行空間計算之地理資訊系統系統,提出一套堰塞湖形成初期之快速分析與評估程序,以提供相關單位研擬堰塞湖之防、減災策略。壽克堅等人利用衛星影像快速對大範圍地區進行崩塌地調查,並據以分析1999集集地震後之崩塌行為。陳桂嘉等人則結合衛星影像判釋結果及相關環境因子,發展土砂災害集水區的生態環境脆弱程度評估模式,此研究成果將有助於未來進行崩塌地復育整治工程時之考量依據。  在研究對象上,可以發現大部分的研究論文皆跟崩塌與土沙災害判釋有關,顯示在台灣因為地震與颱風、豪雨所誘發的坡地災害是大家最關注的,而評估災害對環境所造成的影響也逐漸受到重視。而在影像自動判釋及分析技巧上,大部分論文使用的是逐像元的分類方法(Pixel-Based Classification),其中壽克堅、黃韋凱、陳桂嘉、尹孝元、張崑宗、劉治中、葉堃生等皆提出以NDVI (Normalized Difference Vegetation Index)指標做為崩塌地或土砂之判釋依據,顯見多光譜遙測影像的紅外線資訊於災害判釋中扮演極為重要之角色;此外,數值地形模型(Digital Elevation Model, DEM)、數值地表模型(Digital Surface Model, DSM)等空間資料亦被廣泛用來提升崩塌地之判釋正確性及萃取災害資訊等。而張崑宗等則進一步比較了最大似然法、倒傳遞類神經網路法,及支持向量機等分類方法之優劣。黃韋凱等則採用物件導向分類方法,搭配各種地形地物特徵,以獲取更完整之崩塌地資訊。  雖然航遙測技術在天然災害的「實用性」,遠超過其「學術性」,但是從災害新案例的探討到分析方法的創新,處處都可以有新的發現,亦有其學術上的意義。展望未來,所謂「預防重於治療」,天然災害常見的種類除本專刊所及之地震堰塞湖與豪雨山崩外,尚有火山、地層下陷、洪水氾濫、生態逆境、活斷層、侵蝕、地滑、與土石流等等,其預防的起點在於清點、找出發生的控制因素、以及分析評估未來復發的潛感性等,有待更多更深入的研究。尤其,在緊急救災上,航遙測技術也應該扮演很重要的角色。

Abstract

關鍵字

Keywords

附件檔名

華芸線上圖書館

N / A

備註說明

N / A

Pages:

3-15

論文名稱

遙測影像與數值地形模型於堰塞湖災害評估之應用

Title

Application of Satellite Images and DEM for the Hazard Assessment of Landslide Dams

作者

董家鈞, 劉說安,張立雨,李錫堤,廖志中,潘以文

Author

Jia-Jyun Dong, Yuei-An Liou, L-Y Chang, Chyi-Tyi Lee , Jyh-Jong Liao , Yii-Wen Pan

中文摘要

堰塞湖一旦形成後,衍生災害可概分兩類:第一類為上游迴水淹沒、第二類為潰壩造成下游夾砂水流或洪水災害。遙測技術對於這兩類災害快速評估工作之推動可扮演相當關鍵的角色。本研究整合衛星影像以及數值地形模型,配合可快速進行空間計算之GIS系統,提出一套堰塞湖形成初期之快速分析與評估程序。流程包括:(1)及時取得足夠清晰之衛星影像,判釋堰塞湖位置;(2)配合數值地形模型獲得天然壩之幾何資訊(壩頂高程、壩長、壩寬、壩高)以及上游集水面積;(3)根據數值地形資料繪製水位高程-湖水體積圖,並利用多期衛星影像搭配數值地形模型進行堰塞湖水位高程監測;(4)估計淨入流流量、溢流時間以及上游淹沒範圍與時間之關係;(5)利用地形指標或統計模型以評估天然壩之穩定性。本文以汶川地震於北川形成之唐家山堰塞湖為例,說明如何利用福衛二號影像以及SRTM數值地形資料於第一時間提供堰塞湖防、救災工作推動所需之重要資訊。本研究重要結論包括:(1)地震或極端降雨後,應於可能的最短時間內,取得影像解析度至少能描繪天然壩堆積邊界之清晰衛星影像;(2)評估所需之DEM精度以5公尺為佳;(3)堰塞湖水位高程研判應以堰塞湖水陸交界找尋多點進行高程平均,以提高湖水位高程研判之準確度;(4)堰塞湖後期流量推估對水位高程估計較敏感,因此欲根據遙測影像及DEM進行水位高程監測以及淹沒範圍預測,應注意DEM水平位置及高程誤差可能造成之影響。

Abstract

After the formation of a landslide dam, the related impacts can be divided into upstream (rising backwater) and down stream (dam breaching with outburst flood and debris flow) components. Since both components may occur soon after the landslide dams the river, rapid assessment of the related hazards is crucial. Remote sensing technology could play a key role for decision-making to prevent or minimize the disaster due to a landslide dam. This research proposed a procedure utilizing the satellite images, DEM, and GIS system to quickly assess the potential hazards associated with the formation of landslide dams. To begin with, the location of the landslide dam should be identified from the satellite images. Secondly, the elevation of the landslide-dam top, dam geometry, and catchment area should be determined based on the satellite images and DEM. It follows a production of the water level–lake storage curve of the natural lake. Different periods of the satellite image could be used for monitoring the buildup of the backwater. Consequently, the inflow could be estimated using the water level–lake storage curve and the monitored water level. Based on the estimated inflow, the time for overtopping and the flooding area of the backwater could be determined. Meanwhile, the stability of landslide dam could be evaluated using the geo-morphological and hydro-geological characteristics estimated from the satellite images and DEM. A large landslide dam formed after the 2008 Wenchuan Earthquake is adopted as an example for demonstrating the hazard assessment procedure. The case history successfully illustrated how the high-resolution FORMOSAT-2 satellite images and the DEM derived from Shuttle Radar Topographic Mission (SRTM) could be efficiently served as the powerful tools to provide important information for decision making on the action of hazard mitigation soon after the formation of a landslide dam.

關鍵字

天然壩、水位監測、溢頂破壞、壩體穩定性

Keywords

Landslide dam, Water-level monitoring, Overtopping, Dam stability

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-3-15

Pages:

17-28

論文名稱

以SPOT衛星影像探討1999集集地震後之崩塌行為

Title

Analysis of Landslide Behavior after 1999 Chi-Chi Earthquake by SPOT Satellite Images

作者

壽克堅, 吳秋靜, 許惠瑛

Author

K.J. Shou , C.C. Wu ,H.Y. Hsu

中文摘要

台灣地區受到1999年集集地震之衝擊,地質破碎坡地崩塌嚴重;加以近年來受氣候變遷影響造成颱風降雨強度增強,使得原本脆弱的坡地更易遭受侵襲並造成崩塌災害。本研究以多時期SPOT衛星影像探討1999集集地震後之崩塌行為,為了利用衛星快速對大範圍地區進行崩塌地調查,本研究採用常態化差異指標-坡度(NDVI-Slope)雙門檻值法來做崩塌地判釋。此一雙門檻值法首先利用NDVI值作為分界門檻值找出裸露地,再搭配DTM坡度門檻值將崩塌地進一步判釋出來。但此一雙門檻值法之的判釋可能會受地區性的地形條件、地質條件、植生條件等影響判釋之準確度;因此,不同之流域選用不同之判釋門檻值有其必要。本研究以烏溪為研究區域,考慮賀伯、桃芝、敏督利等三個颱風事件探討各種NDVI及坡度門檻值組合對崩塌地判釋之影響,並以全區域及地層年代分區探討崩塌地之行為。本研究以接受器操作特性曲線(Receiver Operating Characteristic Curve)來分析比較出最佳的門檻值組合,以進行崩塌地有效快速判釋。本研究發現NDVI門檻值設為0.1坡度門檻值設為40%在烏溪以全區域及以地層年代分區的分析有一致性較佳之判釋結果。多時期崩塌判釋結果發現,2001年桃芝颱風時西側靠近車籠埔斷層地區有顯著崩塌地分布外,因桃芝颱風之降雨落在北港溪一帶,使得該區崩塌地比以往更為嚴重。2004年的敏督利颱風,因強降雨造成烏溪流域西北側有顯著崩塌,強降雨未落於北港溪流域,相較桃芝颱風北港溪流域之崩塌有明顯減緩趨勢。集集地震引起的崩塌地在自然癒合但未達邊坡長期穩定狀態下,後續颱風事件仍會因降雨而產生坡地災害,但地震之衝擊效應將隨時間而衰減。

Abstract

Due to the impact of 1999 Chi-Chi Earthquake (MW=7.6), the geology in Taiwan area was more fractured and a tremendous amount of landslides were induced. After 1999, the unusual typhoon events cause the primary and secondary landslide hazard more severe. This study aims to study the landslide hazard by the SPOT satellite images, focusing on the behavior of the primary and secondary landslide hazards after 1999. In order to obtain the landslide distributions efficiently, this study adopted an NDVI-Slope criterion in the GIS image interpretation. Since this criterion could be affected by local topography ore geology, it could be necessary to adopt different criterion for different catchment or sub-catchment. In this study, the Wu His catchment in Central Taiwan was adopted as study area, the landslides induced by three typhoon events, i.e., Herb (1996), Toraji (2001) and Mindulle (2004), were analyzed. In order to obtain an optimal criterion, the analysis of Receiver Operating Characteristic Curve was used. The results showed good interpretation by using the criterion 0.1 of NDVI and 40% of slope in Wu His catchment, for the whole catchment and for its sub-catchments. The landslides distributions showed that significantly more landslides were induced near the Chelungpu Fault by the 2001 Toraji Typhoon. In addition, more landslides were found in the upstream Peikang River sub-catchment, due to the distribution of heavy rainfall. However, less landslides were induced by 2004 Mindulle Typhoon in the Peikang River area, since the heavy rainfall is distributed in the northwestern side of the catchment. The results reveal that the self-healing effect is undergoing, but subsequent typhoon events could still cause above-normal landslides. However, the impact of landslide will decay away gradually.

關鍵字

SPOT、NDVI-Slope雙門檻值法、ROC曲線、烏溪、1999集集地震

Keywords

SPOT, NDVI-Slope Criterion, ROC Curve, Wu Hsi, 1999 Chi-Chi earthquake.

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-17-28

Pages:

29-49

論文名稱

物件導向分析方法應用於遙測影像之分區及崩塌地與人工設施分類

Title

Applying Object-Oriented Analysis to Segmentation and Classification of Landslide and Artificial Facilities with Remote Sensing Image

作者

黃韋凱,林銘郎, 陳良健, 林彥享, 蕭震洋

Author

Wei-Kai Huang , Ming-Lang Lin , Liang-Chien Chen , Yen-Hsiang Lin , Cheng-Yang Hsiao

中文摘要

本研究利用物件導向式遙測影像分析方法進行大範圍坡地與河川災害快速判釋,以改善像元式影像分析方法於分類時常有之雜訊問題。研究使用福爾摩沙二號衛星在莫拉克颱風事件前後遙測影像,利用災害前後期影像同時進行均質化分割技術,於兩張影像上產生出相同區塊,以解決不同時期影像之地貌分類邊界問題;以區塊為分析單元,依照人工判釋經驗與階層式的邏輯,加入合適之空間特徵資訊(包括光譜值、坡度等),訂定分類規則流程,由單純至複雜的地貌進行十四種分類,建立出有系統之分類程序,以作為未來災前後影像快速判釋之參考。 應用於研究區之分類結果,進一步與航照判釋及現地踏勘比對,訓練成果由誤差矩陣評估得整體精度達81.6%;崩壞比由災前的1.5% 增加為10.5%、河道變遷河段達307處,災後河道面積相對於災前增加32%、受影響之開發地達26%、受影響之房舍達26%(1179處)、受影響之道路達幾18%(2281處)。

Abstract

In this study, object-oriented analysis method was applied to interpret landslide and flood disasters before and after Typhoon Morakot with remote sensing images. It is shown that remote sensing images in wide area can be recognized quickly using this method. Two images before and after the disaster were homogeneously segmented to generate the same blocks in order to solve the boundary problem in feature classification. Based on the rules of artificial interpretation, proper information (ex. spectral values, slopes…etc.) was added to construct hierarchical logic, classifying 14 different kinds of features. The classification results are double checked with aerial photographs and field investigation. The overall accuracy of final training outcome based on the error matrix assessment is about 83.3%. The results show that the landslide ratio increased from 1.5% to 10.5%, blocks features of river channel increased 307 sites, area ratio increasing to 32% compared with the original river channel area, 26% of the developed lands were affected, 26% (1179 sites)of the houses were affected, 18%(2281 sites)of the roads were affected .

關鍵字

莫拉克颱風、物件導向、分區、分類、最鄰近法、影像變異、崩塌、人工設施

Keywords

Typhoon Morakot, object-oriented, segmentation, classification, nearest neighbor method, image difference, landslide, artificial facilities.

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-29-49

Pages:

51-64

論文名稱

台東地區土砂災害之生態環境脆弱度評估

Title

Assess Eco-environmental Vulnerability of Debris Disaster Areas in Taitung County

作者

陳桂嘉,吳守從,陳朝圳

Author

Kuei-Chia Chen , Shou-Tsung Wu , Chaur-Tzuhn Chen

中文摘要

知本溪與太麻里溪為台東縣較嚴重的莫拉克颱風土砂災害集水區,崩塌是該集水區內最嚴重的土砂災害類型。本研究目的在於發展土砂災害集水區的生態環境脆弱程度評估模式。研究方法係整合GIS與RS技術,利用因素分析求解崩塌地影響因子權重,並以環境脆弱度指標,評估集水區生態脆弱區域,同時建構以自然環境潛在因子,以及保全對象危害度因子為基礎的崩塌地復育需求模式,並利用莫拉克颱風造成的崩塌地區作為脆弱度區域之驗證。研究結果顯示,除了環境區位因子的干擾外,人為開發亦為崩塌地發生的重要影響因子;在脆弱度分析方面,兩個集水區均顯現崩塌地確實是處於高危險且高脆弱之地區,其中又以太麻里溪集水區最為嚴重,整個區域內被歸類於極脆弱等級之崩塌地高達41.35%。依據本研究所建立的崩塌地復育需求評估模式,顯示太麻里溪集水區崩塌地有較高的復育處理需求,因此研究結果有助未來集水區進行治理及崩塌地植生復育之參考。

Abstract

Among the watersheds in Taitung County, the river watersheds of Zhiben and Taimali are more serious natural disaster areas on typhoon Morakot, in which landslide is the most serious type of sediment disasters in those watersheds. The purpose of this study was to develop a model of eco-environmental vulnerability for the landslide disaster watershed. First, we used the factor analysis to get the weights of landslide causing impact factors. After this, we used environmental vulnerability index (EVI) to assess the eco-environmental vulnerable area of watershed. We also created the assessment model of vegetation recovery that was based on the natural potential environmental factors and the protected object factors. Finally, we used the disasters areas which Morakot created to confirm the frailty region the accuracy. The results indicated that not only landslide occurred was base on the watershed environment at factors, the impact of human activity was also an important factor in these two watersheds. In vulnerability of this study indicated that the landslides were located in high-risk and high-vulnerability areas. Especially, Taimali river watershed was the gravest, and there was 41.35% of landslide belonging extreme level. According to the landslide vegetation recovery assessment model, the First Score (FS) was know that landslide of Taimali river watershed is necessary to give the precedence action. This research can give the guideline of vegetation recovery in future.

關鍵字

生態環境脆弱度、土砂災害、植生復育評估、集水區、莫拉克颱風

Keywords

Eco-environmental vulnerability, Debris Disaster, Vegetation recovery assessment, Watershed, Typhoon Morakot

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-51-64

Pages:

65-78

論文名稱

衛星影像於國土變異監測之應用

Title

Monitoring in Land Surface Changes by Satellite Images

作者

尹孝元, 梁隆鑫, 陳錕山, 黃珮琦

Author

Hsiao-Yuan Yin , Long-Shin Liang ,Kun-Shan Chen , Peggy Huang

中文摘要

國土變遷可分為自然與人為兩方面:自然方面,如海岸線變動、崩塌、土石流及淹水等情形;人為方面,如山坡地違規、違建、濫墾、傾倒廢棄物等。對於地表變動監測,衛星遙測的優勢,不受地表高度限制,且可快速與準確地進行資料處理,對於國土變遷普查,是一個非常有效的工具。其中崩塌與違規濫墾是臺灣地區較常見的山區變動,崩塌是災害,幾乎每年都會伴隨颱風或豪雨發生,違規濫墾造成土石外露是崩塌與土石流素材的來源之一。農委會水土保持局自1995年起,即利用遙測科技進行山坡地管理與監測,結合遙測影像與GIS判釋系統,進行山坡地變異監測及地形變動分析,除了每年皆查獲違法點位之外,間接對想取巧之徒也有嚇阻效果,並減少現場查報人員的人情麻煩。地形變動分析可以對崩塌地判釋、統計分析、與圖資建置,提供最新資訊,做為治災防災之參考。

Abstract

Land surface changes are generally due to natural or human forces. For example, coastal changes, landslide, mudslide, and floods are all triggered by natural forces. While over-developed and illegally waste dumping in slopeland are owing to man-made impacts. Remote sensing as a powerful tool for change detection of wide area land surface can supply fast and accurate processing and analysis. This paper gives an overview about applications of satellite image, including change monitoring of slopeland, landslide analysis, acquiring of surface deformation, and change detection of waterline in west Taiwan. Application of remote science and technology in management and monitoring, including slopeland monitoring and landslide analysis, has been proceeding since 1995 by Water and Soil Conservation Bureau of the Council of Agriculture. These works are all the resources of government’s administration in precaution against natural calamities.

關鍵字

衛星影像、國土變遷、崩塌地

Keywords

Satellite image, land surface changes, landslide, surface deformation

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-65-78

Pages:

79-95

論文名稱

暴雨型崩塌地自動判釋及特徵分析之研究

Title

Automatic Rainfall-induced Landslide Interpretation and Features Analysis

作者

張崑宗, 高啟軒, 王主一, 劉進金

Author

K. T. Chang , C. S. Kao, Z. Y. Wang, J.K.Liu

中文摘要

台灣位在西北太平洋颱風移行的主要路徑上,依據統計平均每年約有3 至4 個颱風可能侵襲台灣地區,伴隨颱風而來的強風豪雨所引發的洪水與坡地土砂崩塌災害,不僅嚴重威脅人民的生命安全,更時常造成社會經濟的重大損失。過去崩塌災情分析方式,常由經驗豐富地質專家進行人工研判,不僅耗時、費力,無法在短時間內做出有效的災害評估與災後復原計畫;且易因高山阻隔或災後道路中斷等因素,使得大範圍災情調查工作無法順利進行。因此,如何提升自動化判別災區崩塌地區域之效能,是一個值得探討的研究課題。 本研究使用高解析衛星影像與地形資料,以提升衛星影像自動化暴雨型崩塌地判釋之精度為目標,除了使用在許多影像分類技術常被採用的最大似然法及倒傳遞類神經網路法外,亦建立以支持向量機法為基礎之崩塌地判釋機制;文中除了對三種方法進行分類精度評估,亦探討影像色調及地形特徵作為暴雨型崩塌地判釋特徵之顯著性,以強化崩塌地分析的自動化及效能。 從分離度分析結果可顯示訓練樣本之選取適當,坡度特徵的加入有助於增加崩塌地與其他三種類別分離度。此外,由分類精度評估結果可知BPNN法與SVM法分類精度均優於ML法;至於判釋特徵,如坡度、OHM等之使用上,對於山崩判釋正確率提升上有不同程度之影響,其中以坡度特徵影響最為顯著。然而,因混合像元效應(本次實驗資料解析度20m)、取樣率不一之影響,對於本研究使用特徵及分類方法,值得進一步探討與分析。

Abstract

Taiwan is located in the northwest Pacific, in a major migration path of typhoons. There are about 3-4 typhoons likely to hit the Taiwan area in average annually. Strong winds and heavy rains are accompanied with typhoons, thus, usually leading to a result of floods and landslide hazards. Not only human lives are seriously threatened, but also social and economic losses might be imposed. It is estimated that the economic loss is about six billion US dollars in every year due to typhoon. Landslide inventory used to be done by manual judgement of experienced geologists. It is a time consuming and labour-intensive job, to lead making effective disaster assessment and recovery plans impossible. And let large-scale disaster investigation can not proceed smoothly due to blocked by mountains or post-disaster factors such as road disruption. Therefore, how to enhance the automation and its performance of landslide inventory is an important research topic. Multi-source high-resolution data, e.g. a SPOT satellite image, 5m x 5m DTM reduced from a LIDAR data and aerial orthophotos, are fused to construct the feature space for landslides analysis in this paper. Then, those spectral and geomorphometric features are used to recognize landslides by a Maximum Likelihood (ML) method, an Artificial Neural Network (ANN) method and a Supported Vector Machine (SVM) method. The classification results are evaluated in comparison with those of manual-interpretation. Moreover, the separability analysis for the used features on rainfall-induced landslide interpretation is also provided. The separability analysis result indicates that slope is an important factor to distinguish the landslide and other classes. In this case study, the recognition accuracy for landslides and non-landslides for the BPNN and SVM method are better than the ones for the ML method. Moreover, slope is a significant interpretation key for landslides recognition. Due to mixed pixel effect (resolution of this experimental data is 20m) and the effect of different sampling rates, the characteristics and assessment for the conducted methods is worth further study and analysis.

關鍵字

暴雨型崩塌地、衛星影像、空載光達、類神經網路、支持向量機

Keywords

Rainfall-induced Landslides, satellite image, airborne LIDAR, Artificial Neural Networks, support vector machine.

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-79-95

Pages:

97-109

論文名稱

三維雷射掃描應用於崩塌土石量化之研究

Title

A Study on the Topographic Changes Using Ground-based 3D Laser Data

作者

蕭國鑫, 劉進金, 曾義星, 王晉倫

Author

Kuo-Hsin Hsiao , Jin-King Liu , Yi-Hsing Tseng , Chin-Lun Wang

中文摘要

本研究利用地面三維雷射掃描儀,針對2004年7月敏督利颱風前後,位於南投縣境內之濁水溪支流陳有蘭溪的支流,竹仔腳坑溪與三廍坑溪上游河道地區進行三維雷射掃描,除製作高解析的高程地形外,並量化颱風前、後之崩塌土石變化。過程為先利用GPS量測基準點坐標,並結合地面覘標控制點的佈設與全測站經緯儀之外業測量,以獲取覘標點的坐標;其次為施行三維雷射掃描後,藉由覘標控制點將多測站掃描資料連結,再利用覘標點的坐標進行坐標轉換,且模型化目標區的三維地形為20公分網格資訊;最後疊合颱風前、後的掃描觀測資料,評估此兩條河道上游崩塌區的土石侵蝕與淤積變化。結果顯示竹仔腳坑溪上游河道於敏督利颱風過後,河道地形侵蝕深度最多達5~10公尺,而三廍坑溪上游土石流潛在地區則淤積了5~10公尺;顯現以地面三維雷射掃描資料監測局部重點地區的地形變化,具有應用潛力。

Abstract

Ground-based 3D laser data are used in this study for the estimation of riverbed topographic change. A point-cloud of high precision and high density can be obtained in a few minutes for the sensitive riverbed areas. With a limited control survey of precise targets using GPS and total stations, multiple scans of ground-based LiDAR can be registered together to form one cohesive 3D model. And, thus, different periods of topographic data are overlaid for estimating the changes of the target areas. Two cases are practiced in this study. In the first case, the scoured riverbed on Zu-Zi-Jiao-Keng stream, a branch of Cho-Shui river in Nan-Tou County was scanned before and after typhoon Mindulle on 2 June 2004, with a total of 15 scans in 5 stations by using ILRIS-3D laser scanner. Subsequently, they were registered and joined and re-sampled to a 20 cm grid. The second case is located in San-Boo-Keng upstream. It is found that in the first case that maximum erosion height of riverbed changes was between 5~10 m. In the second case, the average height of silted-up is about 5~10 m. The effectiveness of applying 3D laser scanning is proved in this study.

關鍵字

崩塌地、數值高程模型、三維雷射掃描儀

Keywords

Landslides, Digital Elevation Model (DEM), Ground-based 3D Laser Scanner.

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-97-109

Pages:

111-122

論文名稱

結合空載LiDAR與彩色航照應用於崩塌地研判

Title

Integrating Airborne LiDAR and Color Aerial Photography for Landslide Interpretation

作者

劉治中, 蕭國鑫, 饒見有, 劉進金,吳哲榮, 黃群修

Author

Chi-Chung Lau , Kuo-Hsin Hsiao , Jiann-Yeou Rau 2 Jin-King Liu , Jer-Rong Wu , Qun-Xiu Huang

中文摘要

本研究結合彩色航照與空載光達資料,藉由半自動化方式辨識崩塌地,並利用三維立體展示的人機操作介面,供人工判釋及編輯崩塌地邊界向量資料。其中彩色航照利用綠度指數,空載光達資料則利用數值高程模型(DEM)與數值地表模型(DSM),除計算地物高度模型(OHM)與坡度資料外,亦結合地表粗糙度(Roughness)來確定崩塌地範圍。初步成果顯示利用上述參數,依訓練樣區統計資料選定適當之門檻值後,可有效地偵測出局部範圍的崩塌區位置;對於誤判的地區,藉由開發的三維立體編修系統,可以透過人工進行必要之修正。另配合崩塌地完整屬性需求,亦設計了及時研判功能,並依崩塌地發生之位置、形狀、滑動面型態及崩塌方式等,建置崩塌地的地質屬性,提供後續之規劃參考用。

Abstract

In this study, a semi-automatic landslide classification method is proposed and implemented using both airborne LiDAR data and color aerial photographs. A man-machine interface is implemented with three-dimensional perspective display capability, thus to ease the manual interpretation and editing after a preliminary result of landslide polygons are generated by an automatic algorithm proposed in this study. Four parameters are used in the automatic algorithm, namely Greenness, Slope, OHM and Roughness. Greenness is derived from color aerial photograph and employed to define non-vegetated land of fresh scars of shallow-seated landslides. All the other tree parameters are derived from LiDAR DSM and DEM to portray the geomorphometric characteristics of landslides. Thresholds are derived automatically from training areas and then are applied in real time to show the distribution of possible landslides. With the 3D interactive interface, the possible landslides are draped on 3D perspective landscape on the screen. This is convenient to assist the human expert to further modify the results by deleting erroneous ones or modify the boundaries of landslides visually. In addition, the interface system can go without the semi-automatic approach and just be used for visual interpretation solely on basis of the expert knowledge of feature locations, shapes, and types of landslides. Attribute table linked with the landslide spatial feature can also be established in this system. It is proved in this study that this is a practical and efficient system.

關鍵字

崩塌地、數值高程資料、空載光達

Keywords

Landslides, Digital Terrain Model (DTM), LiDAR

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-111-122

Pages:

123-140

論文名稱

航攝數位影像於防救災工作之應用

Title

Applying Digital Aerial Images in Natural Hazards Mitigation in Taiwan

作者

葉堃生, 李茂園, 王韻皓

Author

Kuen-Sheng Yeh , Mao-Yuan Li , Uen-Hao Wang

中文摘要

本文簡述農林航空測量所應用新式航攝數位相機配合GPS/IMU進行防救災工作之製圖流程,從航空攝影、軌跡解算、正射影像製作、判釋數化乃至資料提供,並針對近年來發生的重大災害如「阿里山火災」、「八八水災」及「甲仙大地震」,鉅細靡遺地呈現本所從影像取得、高解析度多光譜正射影像製作及後端加值應用等作業方法,展現應用航攝數位影像於防救災工作之具體成果。航攝影像成果可應用在森林火災之NDVI影像判釋、數值地形模型產製、地形變遷偵測等災害之防救上。

Abstract

This paper introduces the mapping workflow of using new digital photogrammetric cameras with GPS/IMU in mitigating natural hazards for the Aerial Survey Office. In the text, we have included detailed descriptions on the procedures of image acquisitions, high resolution and multi-spectrum ortho-image productions, interpretations, digitizations, and data provisions. We also illustrate how these procedures were applied to mitigate catastrophes occurred in recent years, such as "Alisan Fire", "88 Flood", and "Chiahsien Earthquake". The results indicate that high-resolution digital aerial images can be applied to the interpretation of forest fires with NDVI images, production of digital terrain model, change detection, and mitigation of natural hazards.

關鍵字

航攝數位相機、高解析度多光譜正射影像

Keywords

digital photogrammetric camera, high-resolution multi-spectral ortho images, disaster mitigation.

附件檔名

華芸線上圖書館

N / A

備註說明

201003-15-123-140

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