ENGLISH

3卷/4期

3卷/4期

華藝線上圖書館

Pages:

1-14

論文名稱

應用SPOT衛星資料求取大氣氣溶膠光學厚度

Title

Applying SPOT Data to Determine Aerosol Optical Depth

作者

林唐煌 , 劉振榮 , 陳哲俊

Author

Lin Tang-Huang , Gin-Rong Liu , A. J. Chen

中文摘要

假設地表物不變,則衛星觀測地表的變化量可視為大氣變化所引起的,基於這前提下,Tanre 等人於1988年定義一結構函數,並提出由Landsat TM 多時影像求取大氣氣溶膠光學厚度的計算方法。1992 年 Holben 等人將此法應用於 AVHRR 資料亦獲得不錯之結果。但 Tanre 所定義的結構函數僅考慮單一方向,無法完全描述地表的特性,尤其應用於地面解析很好的資料時。本文則將考慮多方向的結構函數並應用於地面解析較佳之 SPOT資料。應用結構函數法求取氣溶膠光學厚度過程中,結構函數分布型態的差異將會造成誤差,而地形和地表覆蓋物的特性以及高地面解析資料則是造成結構函數分布型態上差異的主要因素。因此本研究由結構函數之分布特性,分析選擇一最佳位置數,以消除因結構函數分布型態的變異所造成的誤差。本研究方法和暗密植被的方法比較,結果非常合理,具極高之可行性。

Abstract

By assuming that the ground reflectance is constant, variations of satellite signal may be attributed to variations of the atmospheric optical properties. Based upon this, Tanre et al., 1988 has defined the structure function for deriving aerosol optical depth from TM images. Holben (1992) also has gotten the similar results using AVHRR data. Basically, the structure function is defined by single direction only. It can't represent the complete properties of the surface structure. To over­come this, a multi-directional structure function, which should include more information than the single directional from the surface structure, is used in this paper to improve the structure function method for SPOT data. In general, the error of aerosol optical depth determination could be enlarged by the different pattern of structure function distribution which is caused by the characteristics of local land­covers, terrain and the high resolution property of SPOT data. In order to reduce such error, it is necessary to determine an optimum number of distance to truncate the different pattern of structure function distribution. After these improvements, the results of this study are reasonable when compared with the Dense Dark Vegetation method's results.

關鍵字

結構函數、氣溶膠光學厚度、SPOT

Keywords

Aerosol optical depth, Structure function, SPOT

附件檔名

華芸線上圖書館

N / A

備註說明

199812-3-4-1-14

Pages:

15-37

論文名稱

森林植被與地形因子對 TM 光譜資訊影響之研究

Title

Study on the Effects of Forest Cover and Relief Factors on TM Data

作者

林金樹

Author

Chinsu Lin

中文摘要

森林植物之生長與分佈受林區地形之影響極大,利用遙測技術檢測森林植群時應考慮森林環境因子對光譜資訊之影響。本文以林區坡向、坡度、表面粗糙度、天空光比例因子、地形結構因子、直射光比例因子以及地類因子為變數,利用複因子試驗方法分析各項因子對 TM 資訊影響之效應,期能提供林業遙測應用之參考。研究結果顯示,坡向、坡度、表面粗糙度、天空光比例因子、直射光比例因子以及地形組構因子等地形因子,彼此具有極顯著的相關,其中以坡向因子所含異質性資訊最大。TM光譜波段中以近紅外光對坡向最敏感,其次為中紅外光和綠光,最低為紅光、藍光以及遠紅外光。天空光比例因子、直射光比例因子以及地形組構因子三者對 TM 光譜資訊綜合性的影響力極小,不顯著,在森林遙測時應可略之。地類、坡向、表面粗糙度以及坡度四者具有顯著的交感效應,證明相同的地類可能因坡向、表面粗糙度和坡度之不同,而有顯著不同的光譜反射值,這應是林區植生被覆影像分類準確度不高的原因。表面粗糙度為次像元資訊,在決定 TM 光譜資訊上有很重要的影響,未來有必要重建林區較高精度的 DTM 資料,以利自然資源遙測之研究與實務之應用。地類光譜分析結果顯示,針葉樹和闊葉樹二大林型光譜混淆的情形較嚴重,但仍可利用綠光 (TM2) 與中紅外光 I(TM5) 二個波段分辨之。茶園、草地以及農地等開發性質地類的光譜特徵在紅光 (TM3) 、中紅外光II(TM7) 和近紅外光 (TM4) 三個波段的異質性最高,可利用該三個波段辨識之。TM 六個反射光譜波段均可辨識裸地和竹類。利用遙測資料檢測森林植被資訊時,必須注意植群樣本之純度與多樣性,方可有效提升分類準確度。

Abstract

Mountainous relief can affect the growth and distribution of vegetation. This must be considered when using remote sensing techniques to detect forest vegetation. This study use factorial experiment method to examine the effects of relief factors and land cover on TM data. It aims to upgrade the efficiency of forest monitoring by use of the satellite image. Relief factors used in this study are aspect, slope, surface roughness, sky view factor (SVF), terrain configuration factor (TCF), and direct light ratio (DLR). Results reveal that there are significant relationships between these relief factors, in which the spectral information explained by the aspect was different from the others. The infrared band (TM4) data is most sensitive to aspect variation in all of the TM bands. Few TM data variation explained by SVF, DLR, and TCF in the case of land cover, aspect, surface roughness, and slope factors exist. So, these three factors could be neglect in related forest studies with remote sensing. The significant interactions between land cover, aspect, surface roughness, and slope factors have proven that vegetation could have very different spectral value in different conditions of such factors. That is why low classifi­cation accuracy occurs in most of the forest studies with satellite image in Taiwan. Surface roughness is present for the relief information in a pixel and is an important factor, which could affect the variation of TM data. Therefore, it is necessary to generate a better preci­sion of DTM data. After that a more perfect experiment could conduct to get a better understanding of mountainous conditions. Based on the pre-list findings, we select a lot of training samples to accomplish maxi­mum likelihood classification. The overall accuracy is about 90 percent. The spectral charac­teristics of conifer and broad-leaf trees are very similar, but the green and the first mid-infrared band data (TM2 and TM5) still could distinguish them. Red, infrared, and the second mid-infrared channel data could extract tea field, grass, and farmland. The spectral characteristics of bamboo and bare land are very distinctive from other cover type in all reflective TM bands.

關鍵字

森林、地類、地形因子、遙測

Keywords

Forest, Land cover, Relief factor, Remote sensing

附件檔名

華芸線上圖書館

N / A

備註說明

199812-3-4-15-37

Pages:

39-52

論文名稱

以碎形為基礎的內插模式與雙線性、立方迴旋內插的比較

Title

A Comparison of Fractal- based Interpolation, Bilinear Interpolation, and Cubic Convolution

作者

黃金聰 , 史天元

Author

Jin-Tsong Hwang , Tian-Yuan Shi

中文摘要

本研究將兩種以碎形布朗運動(fractional Brownian motion,fBm)為基礎的內插方法,與兩種傳統上經常使用的雙線性內插、立方迴旋內插法作比較。實驗數據是經過數化處理後的航空像片立體對。原始影像經重新取樣,疏化為較低空間解析度的影像後再以各種方法內插重建。由實驗結果顯示,將內插重建的影像與原參考影像做比較時,不論是由影像匹配的結果來評估,或是以包括均方根誤差、均值誤差、相關係數及最大誤差量等統計指標,都顯示出傳統的內插方法仍優於碎形內插模式。

Abstract

This study compares two fractal interpolation schemes based on fractional Brownain motion (fBm) with two conventional interpolation schemes: bilinear interpolation and cubic convolution. Numerical experiments are performed with one pair of digitized stereo photographs. The original image is reduces to a lower spatial resolution for interpolation. The statistic indices such as the root mean square error, average error, maximum devia­tion, and correlation coefficient derived by comparing interpolated and the reference images are applied for the evaluation. Besides, an image matching based on least squares is also utilized for comparison. All quality measures indicate that the conventional interpolation schemes are better than the fractal-based schemes.

關鍵字

碎形、布朗運動、變異元

Keywords

Fractal, Brownian motion, Variogram

附件檔名

華芸線上圖書館

N / A

備註說明

199812-3-4-39-52

Pages:

53-61

論文名稱

路廊評選之遙測地質災害調查

Title

Remotely-sensed Geohazards for Assessing Alternative Corridors

作者

劉進金

Author

Jin-King Liu

中文摘要

台灣的三分之二以上地區為坡地,橫跨山區是建設國道系統的關鍵。因為台灣處於板塊的衝撞地帶,所以克服複雜的地質條件是國道興建在技術上最困難的問題。這些地區過去地質資料匱乏,又高山阻隔,傳統方法作大面積調查缺乏時效。因此,衛星影像與航照之判釋分析的成果圖成為國道初期規劃重要的參考來源。1989 年之後遙測技術陸續應用於國內國道初期規劃的地質潛在災害調查。根據六個應用案例,在國道規劃初期最有實效的遙測成果為潛在山崩圖與主要線型構造圖。在平坦地區,三四十年前的航照可以顯示古河道、古池塘、以及都市開發前的地表狀態。至於丘陵地與山區,因為地質破碎,破碎帶之岩體的強度很低,而且易於有地下水流動,使地層極度不穩,所以潛在山崩圖與主要線型構造圖的測繪有助於路廊的評選。因此,遙測地質災害圖在資料匱乏的台灣可以提供國道建設初期規劃之路廊評選重要的參考。

Abstract

More than two thirds of Taiwan Island are covered by rugged terrain. The most difficult part of constructing a sound national highway system in Taiwan is to manage the difficulties of crossing the mountainous terrain, where geological hazard-prone areas are expected but existing geological information are still lacking. Therefore, remotely-sensed data have been employed very extensively since 1989 to give information on geo-hazards. It was also found that the usage of air-photos taken 40 years ago, can be readily identified to give indications of geological sensitive areas such as abandoned river courses and ancient ponds in the level and hilly terrain, where now are covered by recent deposits and are highly cultivated. It is, therefore, concluded that when conventional aerial photographs are employed together with satellite images, the best benefit by using remote sensing techniques can be gained. In mountainous terrain, images can be used to locate potential land­slides; and, in hilly or level terrain, images can be used to identify weak and sensitive geological units. This information is valuable for assessing alternative highway corridors.

關鍵字

路廊、遙測、地質災書、地質敏感區

Keywords

Corridor, remote sensing, geohazard, geological sensitive areas

附件檔名

華芸線上圖書館

N / A

備註說明

199812-3-4-53-61

Pages:

63-70

論文名稱

航空測量及遙感探測名詞之商榷

Title

Discussion of the Terms Used in Photogrammetry and Remote Sensing

作者

謝仁馨 , 張芝生 , 陳哲俊 , 陳佳元 , 吳究 , 伍肇雄 , 孫秉良

Author

Jen-Hsing Hsieh , Chih-Sheng Chang , Che-Tsun Chen , Chia-Yuan Chen , Ju Wu , Chiuo-Hsiung Wu , Bing-Leung Sun

中文摘要

國內第一本「測繪學辭典」,正由國立編譯館聘請測量學者專家40餘人編輯中,其中包含航空測量與遙感探測辭彙千餘則。為集思廣益,將其中部分航測遙測名詞提出商討,歡迎指正。待商討之名詞包括掃瞄、方位、數值、數值地型、連接點、尺度點、立體像片、資料、航帶攝影、全像、仿射測圖等,並附海峽兩岸航測遙測名詞對照表參考。

Abstract

The first Glossary of Surveying and Mapping in Chinese is being compiled by National Institute for Compilation and Translation. The Glossary Committee consists of 40 profes­sors and experts. There are approximately one thousand terms of photogrammetry and remote sensing included in the glossary. The terms listed below are to be discussed for refinement of their definitions. These terms are scanning、orientation、digit、pass point、tie point、DTM、DEM、image、scale point、stereomate、data、continuous strip photograph、holography、affine plotting、and etc.

關鍵字

航空攝影測量學、遙感探測、方位、數值地形模型

Keywords

Aerophotogrammetry, Remote Sensing, Orientation, Digital Terrain Model

附件檔名

華芸線上圖書館

N / A

備註說明

199812-3-4-63-70

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