ENGLISH

10卷/2期

10卷/2期

華藝線上圖書館

Pages:

129-138

論文名稱

多重影像中線型特徵物與物空間直線進行匹配之研究

Title

Matching of Line Features from Multiple Images onto Straight Lines in Object Space

作者

傅俊淇,王蜀嘉

Author

Chun-Chi Fu,Shue-chia Wang

中文摘要

在以航空影像進行自動化建物模型的重建時,常以搜尋建物邊緣線為出發。但在多張影像中進行這個工作時,由於一般低階灰值邊緣線的萃取及鏈結只顧及了影像中的灰值變化以及像空間內簡單二維幾何特徵,並不容易辨識出所搜尋到的邊緣線是否共軛。再加上影像中雜訊、陰影、遮蔽、弱反差或是建物本身紋理繁複的影響,以致於一開始所萃取的邊緣線常是破碎、不連續,而且還含有許多非建物邊緣線。由於萃取時並未考慮建物邊緣在物空間中三維知識,以致於所得到的邊緣線大部分與實際物空間邊緣線並不一致。本研究乃以物空間的觀點找出建物邊緣線在物空間和影像空間中具有的關係,以一個適當的函數模式,來把多張影像中萃取出的邊緣線在物空間中匹配成直線。並藉由實驗找出正確匹配時,此模式應具有的統計特性,建立適當的統計檢定方法,供自動判斷匹配是否成功的依據。

Abstract

Building reconstruction from aerial images begins often with the search of building edges. But searching of conjugate building edges in multiple images is not an easy task. Since low-level edge extraction in image space can only take consideration of gray-level changes and make very simple linking of edge pixels based on very simple criteria like direction of gradient, gray value consistency along edges, etc., thus no information from object space is considered in that stage, a large percentage of the extracted gray-level edges are not building edges at all. More over, due to noises, shadows, occlusions, weak contrast or even due to complexity of building surface texture itself, most of the extracted building edges are not even complete. They are broken and shown only as piecewise line segments. Since gray-level edges are projected images of true edges in object space, the search for conjugate building edges in multiple images should be more successful if information from object space could be taken into consideration. It is thus the aim of this article to describe how simple object space knowledge of straight edges could help the search for conjugate line segments in multiple images. Functional model for matching of the image space line segments onto object space straight lines are derived and statistical testing procedures for testing the correctness of the matching are developed.

關鍵字

建物重建、建物邊緣線、多張影像、邊緣線匹配、物空間匹配

Keywords

building reconstruction, building edges, multiple images, edge matching, object space matching

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-129-138

Pages:

139-158

論文名稱

衛星遙測海面溫度應用於黃鰭鮪漁場變動之研究

Title

A Study on the Variation of Yellowfin Tuna Fishery Ground from Satellite-derived Sea Surface Temperatures

作者

翁筱郡,郭南榮, 何宗儒,陳俊德

Author

Hsiao-Chun Weng,Nan-Jung Kuo,Chung-Ru Ho,Chun-Te Chen

中文摘要

本文利用1996至2001年NOAA衛星酬載之高解析度輻射計(Advanced Very High Resolution Radiometer, AVHRR)之表水溫資料及太平洋共同體秘書處(The Secretariat of the Pacific Community, SPC)之鮪釣漁獲資料,探討聖嬰/反聖嬰對熱帶太平洋及澳洲沿岸黃鰭鮪鮪釣漁況之影響。本文主要利用經驗模態分解法(Empirical Mode Decomposition, EMD),取出與聖嬰/反聖嬰相關之本質模態函數(Intrinsic Mode Function, IMF)進行分析。研究結果顯示當聖嬰現象發生時中西太平洋之黃鰭鮪釣獲率呈現降低之趨勢,且緯向漁場重心向西移動,反聖嬰時則反之。至於東太平洋海域黃鰭鮪釣獲率受聖嬰/反聖嬰影響較中西太平洋明顯,但緯向漁場重心則無明顯變動。澳洲沿岸因位於陸地邊緣且離赤道較遠,黃鰭鮪釣獲率及緯向漁場位置變動受聖嬰/反聖嬰影響並不明顯。

Abstract

In this study the NOAA satellite AVHRR Sea Surface Temperature data and the Secretariat of the Pacific Community (SPC) longline fishery data from 1996 to 2001 are analyzed to discuss the effect of the El Niño/La Niña events on the longline fishery of yellowfin tuna in the Pacific Ocean. The Empirical Mode Decomposition (EMD) method is used to retrieve Intrinsic Mode Function (IMF) related to the El Niño/La Niña events. The results indicate that the evolution of El Niño/La Niña event causes the decreasing/increasing of the hook rate and westward/eastward movement of the Catch Per Unit Effort (CPUE) zonal center of the yellowfin tuna around the Equatorial Pacific. Meanwhile, a nearly simultaneous response between El Niño/La Niña event and yellowfin tuna longline fishery occurs in the eastern part of the Equatorial Pacific, while about 7-9 months lag for yellowfin tuna fishery in the western Pacific. We also find that the El Niño/La Niña event shows no clear influence on the yellowfin tuna fishery in the Southwest Pacific near Australia.

關鍵字

表水溫,聖嬰/反聖嬰現象,太平洋,黃鰭鮪,經驗模態分解法,本質模態函數

Keywords

Sea Surface Temperature, El Niño/La Niña event, Yellowfin tuna, Pacific Ocean, Empirical Mode Decomposition, Intrinsic Mode Function.

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-139-158

Pages:

159-168

論文名稱

多偏極雷達影像斑駁減抑之研究

Title

A Study of Speckle Reduction for Multi-polarization SAR Images

作者

王志添, 陳錕山,胡婕美

Author

C.T. Wang,K.S. Chen,C.M. Hu

中文摘要

就SAR影像觀點而言,當地表粗糙度與雷達波波長相近時,雷達回波將有同調性干擾現象產生斑駁雜訊造成SAR影像判釋上的困難。多偏極資料係以交替改變偏極方式取像,其斑駁效應遠大於單偏極資料,因此斑駁雜訊減抑成為ENVISAT-1雙偏極雷達影像資料於應用方面之重要課題。在斑駁減抑約制條件為不改變影像上均質目標平均值與降低影像斑駁雜訊,兼顧保有影像解析力,且在不同偏極間振幅差值應維持不變。因此在處理兩張偏極影像時,我們先分別對兩偏極影像作雷達特性統計模式分析,以線性化轉換作為多偏極斑駁減抑處理以降低兩偏極之相關雜訊。我們以ENVISAT-1於2003年6月16日所獲取之雙偏極(HH/HV)影像作為測試資料,經上述斑駁減抑處理後,兩張影像之等效觀點數皆由原約3 觀點數提升至約6觀點數,同時在影像上仍能保有點目標地物特徵,說明本文提出之方法有效減抑斑駁雜訊,同時保有原空間解析力,改善交替偏極影像於目標辨識上應用。

Abstract

Multi- polarization SAR imagery data are important for a wide range application such as retrieval of soil moisture, vegetation mapping, and terrain cover classification. However, these alternative polarization data suffer more serious speckle noise caused by the alternating scanning. Speckle noise is inherently induced from the coherent processing of the backscattered signals and substantially degrades the effectiveness of images interpretation and target recognition/identification. To facilitate scene interpretation and qualitative applications of such SAR images, the speckle noise must be reduced to an acceptable level while preserving the polarimetric properties between different polarization data. In this article, we proposed an effective approach that stems from a processing a series of images. A linear transformation that decorrelates the multi-polarization was carried out, followed by the Lagrange multiplier method to find a set of optimal filtering weights that are related to local image statistics. The effectiveness of the method was verified using the ENVISAT-1 Alternating Polarisation Mode HH/HV images acquired on 16th June 2003 over Taiwan. It is found that the equivalent number of looks (ENL) is greatly improved from 3 to 6, and the strong targets are well preserved without scarifying the spatial resolution.

關鍵字

ENVISAT-1、斑駁雜訊、濾波、交替偏極(Alternating Polarisation)

Keywords

ENVISAT-1、Speckle noise、Filter、Alternating Polarisation

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-159-168

Pages:

169-182

論文名稱

地面光譜資料與SPOT 影像應用於水質定量推估研究

Title

Water Quality Estimation Using Spectroradiometer and SPOT Data

作者

蕭國鑫,吳啟南,廖子毅

Author

Kuo-Hsing HSIAO,Chi-Nan WU,Tzu-Yi LIAO

中文摘要

SE-590地面光譜輻射儀(Spectroradiometer)於接近同一時刻,量測德基水庫水體與標準白板的光譜輻射強度(radiance),換算為反射率後,再與水質檢測之葉綠素A、懸浮固體與透明度等參數施行多元迴歸分析(multiple regression)。另亦以德基水庫為例,利用同一天獲取的SPOT影像、SE-590 高光譜資料模擬SPOT三個波段的光譜輻射值,再分別與各水質參數進行迴歸分析及評估迴歸統計資訊;結果顯示SE-590資料定量推估葉綠素A、懸浮固體與透明度水質的標準差為0.57μg/l、0.2mg/l及0.17m,SPOT 資料推估之標準差為1.03μg/l、0.51mg/l及0.32m,SE-590資料模擬SPOT 三個波段推估水質的標準差為1.77μg/l、0.49mg/l 及0.37m。另以遙測多光譜影像之紅/綠及紅/近紅外光段比值法,定性分析水體中的葉綠素相對濃度分布,並確定比值愈小,葉綠素相對含量愈高。

Abstract

A field spectroradiometer was used to measure the spectral reflectance of water body. The reflectance was calculated as the ratio of surface water radiance to the standard whiteboard radiance nearly measured at the same time. Water samples were taken simultaneously for determining their chlorophyll-a, suspended solid and transparency. The relationships between those water quality parameters and spectral reflectance were analyzed using stepwise multiple regression to derive optimal prediction models. The multiple regression was also applied to the SE-590 simulated SPOT bands. The SPOT image of the same day was also analyzed using the same method to compare the statistical results. It shows that the multiple regression models using the SE-590 reflectance data can get the best water quality prediction results. The evaluated RMS error of chlorophyll-a, suspended solid and transparency of water quality parameters are 0.57 ug/l, 0.2 mg/l and 0.17 m, respectively, and the RMS errors are 1.03 μg/l, 0.51 mg/l and 0.32 m for SPOT data, respectively. The SE-590 simulated SPOT three bands data obtained the worst results because the RMS errors are 1.77 ug/l, 0.49 mg/l and 0.37 m. Further, The band ratio of red/green and red/NIR were used to detect the chlorophyll-a relative distribution qualitatively, and assures that the ratio is less, the chlorophyll-a is abundant in TEKEE reservoir.

關鍵字

遙測、光譜輻射儀、水質、營養狀態

Keywords

Remote sensing, Spectroradiometer, Water quality, Trophic state

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-169-182

Pages:

183-190

論文名稱

「科技短文」嚴密幾何模式與有理函數模式於QuickBird 衛星影像幾何改正之比較

Title

Comparisons of Rigorous Sensor Model and Rational Functions Model for QuickBird Images

作者

張智安,陳良健

Author

Tee-Ann Teo,Liang-Chien Chen

中文摘要

本研究之目的為使用QuickBird 衛星影像進行嚴密幾何改正模式(Rigrous Sensor Model, RSM)及有理函數幾何改正模式(Rational Functions Model, RFM)之比較。嚴密幾何改正使用載體參數修正模式,以衛星載體資料(On-Board Data)所提供之軌道為初始值,將衛星軌道修正量視為時間之低階多項式,以地面控制點進行修正,在地面控制點足夠時,使用最小二乘過濾模式對軌道進行過濾修正。有理函數幾何改正模式,研究中使用衛星公司提供之有理函數轉換係數(Rational Polynomial Coefficients, RPC)建立物空間與像空間之轉換關係,並使用地面控制點提升有理函數幾何改正模式之精度。實驗結果顯示,就QuickBird 原始影像而言,使用嚴密幾何改正模式及有理函數幾何改正模式,在使用9 個地面控制點時,其檢核點均方根誤差於像平面上可達2 個像元以內之精度。

Abstract

This investigation is to compare the geometric precision of Rigorous Sensor Model and Rational Function Model for QuickBird images. In the Rigorous Sensor Model, the on-board data are used to initialize the satellite orbit. Then, we employ the ground control points for preliminary orbit fitting. Finally, a least squares filtering technique is applied to collocate the orbit. In the Rational Function Model, the Rational Polynomial Coefficients provided by the satellite company are used to build up the transformation between object space and image space. Then the bias of the transformation is compensated by an affine transformation using ground control points. Experimental results indicate that, both of the RSM and RFM may reach an accuracy of 2 pixels when 9 ground control points are employed.

關鍵字

QuickBird 衛星影像、嚴密幾何改正模式、有理函數幾何改正模式

Keywords

QuickBird Satellite Images, Rigorous Sensor Model, Rational Functions Mode.

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-183-190

Pages:

191-202

論文名稱

「科技短文」航測與三維雷射掃描資料應用於九份二山地形變化分析

Title

Topographic Change Detection Using Aerial Photogrammetric Survey and 3D Laser Data in Jiu-fen-er Mountain

作者

蕭國鑫,劉進金,游明芳,曾義星

Author

Kuo-Hsin Hsiao,Jin-King Liu,Ming-Fang Yu,Yi-Hsing Tseng

中文摘要

本研究利用可在短時間內獲取高密度與高精度的三維雷射掃描資料,針對1999/09/21集集大地震後的九份二山崩塌地形,配合少數地面控制點佈設與野外測量,以獲取大地座標資訊;同時亦進行地面三維雷射多測站掃描,並將掃描資料連結與進行座標轉換,再模型化目標區的三維資訊;最後綜合地震前的40公尺網格DEM資料、地震後的航測高程、空載與地面三維雷射掃描資料,以評估九份二山順向坡大崩塌的地形變化。初步比較地震前、後高程差異較大地區可達60公尺,平均高差為38公尺。另以三維雷射掃描資料,比較地震後崩塌底部局部地區的高程差異,最大約6公分;因而空載三維雷射資料應用於監測此地形變化量尚無可行性。

Abstract

The evaluation of topographic change has been done on basis of 3D laser data and aerial photogrammetric survey. The newly-developed, time-saving approach is by using airborne and ground-based Lidar. A points-cloud of high precision and density distribution can be obtained in a few minutes for the sensitive latent landslide area. 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, overlaid the different period topographic data for estimating the changes of the target areas. This is conducted to observe the deformation of a large-scaled dip-slope landslide of Jiu-fen-er mountain, which was triggered by the big shock of the Chi-Chi earthquake at Nantou County of central Taiwan on 1999/09/21. Control points are systematically distributed on the 1000m by 2000m landslide surface. Surveys are made by transits of total stations, GPS, airborne Lidar and ground-based Lidar data. The terrain changes on ground surface have been detected in thus a scheme. It is found the largest and average changes of height between the earthquake events are about 60m and 38m. The effectiveness of applying 3D laser scanning is proved in this study.

關鍵字

崩塌地、數值高程資料、光達影像

Keywords

Landslides、Digital Terrain Model (DTM)、Lidar

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-191-202

Pages:

203-212

論文名稱

「科技短文」遙測技術應用於台灣中部集集地震災區崩塌地植生處理工程之植生指數評估

Title

Applications of Remote Sensing on Evaluating Vegetation Index of Landslides Induced by Chi-Chi Earthquake in Central Taiwan

作者

蔡光榮,陳建富

Author

Kuang-Jung Tsai, Chien-Fu Chen

中文摘要

遙感探測應用於環境災害監測、生態系變化、地貌判釋分析之應用技術日益成熟,唯以地表植生覆蓋率作為建置地震災區環境潛勢災害風險評估模式之植生復育因子時,實難以單一植生指數方程式進行分析;故本研究乃根據數位學者提出之八種植生指數估算方程式,應用ERDAS IMAGIME8.5之Spatial Modeler Language模組撰寫八種植生指數轉換程式,據以比較中部地震災區118處崩塌地植生處理工程成果,並以統計檢定分析法,找出最適用於研判中部地震災區之崩塌地治理區植生復育判定指標值;經遙測影像分析結果得知,由Huete所提出之土壤調整植生指數(SAVI)方程式在大氣散射及不同土壤環境反射作用下,其判定植生復育指標參數值遠大於其他七種植生指數估算方法,故本研究選定SAVI作為中部地震災區潛勢環境災害風險評估模式中之植生因子指標,並據以作為後續相關植生工程研究之重要參考方向。

Abstract

Remote sensing applied on monitoring environmental disaster and ecological impact has been widely used in Taiwan. However, the recovery of vegetation was identified as one of the key factors contributed to establish an environmental risk assessment model. In reality, it was so difficult to choose an optimal vegetation index equation used to quantify the vegetative factor. Spatial Modeler Language(SML) based on ERDAS IMAGINE software was used to develop eight different vegetative index transformative equations from different aspect of eight researchers. Also, 118 disaster areas rehabilitated by vegetation were chosen as studied samples in this study. Test of homogeneity and analysis of covariance (ANOVA) were also utilized to identify the most suitable equation for estimating vegetation index in studied area. As a result, soil adjusting vegetation index (SAVI) equation developed by Huete was much better than others on the basis of considering atmosphere scattering and ground soil image reflection. This result offers a good reference to help us choose SAVI as one of the best model can be used to estimate the vegetation index. This index became a key factor contributed to create the environmental risk assessment model.

關鍵字

遙感探測、植生指數、崩塌地

Keywords

Remote Sensing, Vegetation Index, Landslide

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-203-212

Pages:

213-224

論文名稱

「科技短文」模糊動態學習神經網路之演算參數

Title

The Algorithmic Parameters of a Fuzzy Dynamic Learning Neural Network

作者

曾裕強,周念湘

Author

Y. C. Tzeng,N. S. Chou

中文摘要

傳統的類神經網路分類器在進行訓練時,係以單一像元單一類別來表示其資訊。因此,對於像元內類別混合的情形並未加以考慮,致使其分類準確度降低。模糊動態學習神經網路以動態學習神經網路為基礎,並利用模糊集合來表示其訓練資訊。為將模糊資訊加入神經網路中,模糊動態學習神經網路在訓練階段利用模糊c平均演算法來設定每一像元的隸屬度。本論文將模糊動態學習神經網路應用於合成口徑雷達影像的分類,以來討論模糊c平均演算法中包括隸屬權值指數及差異度量測等演算參數的選擇。同時,本論文將以合成口徑雷達影像的分類,來比較動態學習神經網路及模糊動態學習神經網路的效能。實驗結果顯示模糊動態學習神經網路具有比動態學習神經網路更好的收斂特性及分類結果,且可改善相似類別間的區別率及類別混合像元之分類能力。

Abstract

When applied to remote sensing imagery classification, the conventional neural network classifier represents training information in a one-pixel-one-class basis. Therefore, the class mixture of a pixel cannot be taken into account resulting in poor classification accuracy. Based on the original dynamic learning neural network (DL), this paper introduces a fuzzy dynamic learning neural network (FDL) in which the training information is represented as fuzzy sets. In order to add the fuzzy information to the neural network, a fuzzy c-means clustering algorithm is used to assign the degree of membership of each pixel during the training stage. In this paper, the FDL is applied to a SAR image classification to evaluate the selection of the algorithmic parameters including the membership weighting exponent and the measure of dissimilarity. Furthermore, comparisons between the DL and FDL are made. The effectiveness of the combination of the neural network and fuzzy sets theory is demonstrated by an example of SAR image classification. Experimental results show that the separatability between the similar classes and the classification capability of the class-mixed pixels are improved. Moreover, the classification results match better with the ground truth.

關鍵字

隸屬度、隸屬權值指數、差異度量測、合成口徑雷達

Keywords

degree of membership, membership weighting exponent, measure of dissimilarity, SAR

附件檔名

華芸線上圖書館

N / A

備註說明

200506-10-2-213-224

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