ENGLISH

3 卷 / 1 期

3 卷 / 1 期

華藝線上圖書館

Pages:

1-12

論文名稱

建立地理資訊系統中資料選取知識之研究----以支援遙測影像分類為例

Title

A Knowledge Perspective about Data Selection in GIS ---Using Image Classification Aid as An Example

作者

陳振南 , 洪榮宏

Author

Cheng-Nan Chen , Jung-Hong Hong

中文摘要

隨著現況資料取得技術的日益進步,如何管理資料以便資料獲得妥善的應用成為有待突破的瓶頸。以遙感探測為例,根據過去研究的成果顯示若能從地理資訊系統中提供適當的輔助資訊,將可有效提高分類辨識的正確性及時效性。本研究即由上述觀點出發,探討從地理資訊系統中自動取出資料以供其它領域應用之可行性,並討論使用者可能的需求及地理資訊系統可能有那些符合需求的資料,以此為基礎來建立需求與資料之間對應的知識法則進而解決不同領域對資料定義上的問題。研究之觀點涵蓋了使用者需求、知識法則的設計及地理資訊系統詮釋資料的設計,以此建立選取合適於影像分類之輔助資料的知識庫基本架構。最後以遙感探測影像分類為例實際建立一個知識庫系統,並透過所舉的範例來操作並測試所建立的系統。隨著知識庫系統功能的增強可預期將使地理資訊系統與遙感探測達到更緊密的結合。

Abstract

Techniques of GIS data acquisition have been steadily improved over the past years, therefore, how to efficiently manage these volumes of complex data and effectively take advantage of their existence become a bottleneck for the future GIS development. Past research demonstrated that the accuracy of image classification can be improved by introducing ancillary information like landcover or landuse data. This research focuses on the data selection process in the GIS environment. We suggest a knowledge-based approach, which replaces the human users ‘interpretation and judgement with a knowledge base loaded with rules about human spatial and domain knowledge. The system is designed to understand users, requirement, infer their requirement with the understanding about GIS data, and then transform the requirement to a query executable with GIS DBMS. It is expected to solve the semantic gap about reality phenomena due to the different definitions from application domains(e.g., remote sensing) and existing GISs. This research started with a general analysis about building a KB based on the understanding of GIS data, we then use remote sensing image classification as examples to demonstrate how a KB can help choosing appropriate ancillary information to meet certain domain requirement. With careful selection and formalization of spatial and domain knowledge, it is optimistic to expect GISs to be able to meet more domain needs in the future.

關鍵字

地理資訊系統、知識庫、遙感探測、專家系統

Keywords

Geographic Information System, Knowledge Base, Remote Sensing, Expert System

附件檔名

華芸線上圖書館

N / A

備註說明

199803-3-1-1-12

Pages:

13-28

論文名稱

甘藷植被光譜之季節變化

Title

Seasonal Changes in Canopy Spectra of Sweet Potato

作者

楊純明 , 葛齊家

Author

Chwen-Ming Yang , Chi-Chia Ko

中文摘要

近年來以衛星多光譜遙測資料分析地面植被覆蓋及發展植被外觀徵狀模式之研究蓬勃進展,惟常因缺乏地面光譜遙測資訊的配合,使得解析之精確度與準卻度稍嫌不足。植物生育全期持續而詳細地光譜測定,不僅有助於判別不同生育階段植被之光譜差異,同時可利用於區分該植物種類或品系光譜之特徵波長。本文研究乃於 1995 及 1996 年偵測田間栽培之甘藷(Ipomoea batatas cv. Tainung 57) 地上部植冠(植被)反射光譜(波長範圍介於 350-1100 nm),並試以釐清其光譜特徵波長。根據試驗結果,兩不同生長期所測得之反射比光譜曲線類似,惟均受到環境與植株生長狀況影響。在反射光譜之輻射量上,以紫外線波段 (740 nm) 最高,介於 70-80% 。甘藷反射輻射量光譜及反射比光譜類同於其他綠色作物之趨勢表現,由前項光譜曲線之波峰及波谷發現 28 條特徵波長,而後項反射比光譜則具有 6 條特徵波長,兩生長季節均相同。自反射輻射量光譜中找出 3 特徵波長,分別為554 、688 、及 754 nm,以計算各項植被指數。各植被指數全期回歸曲線呈曲線趨勢,一般言曲線隨生長高峰達到頂點,再隨成熟老化而下降。

Abstract

In recent years use of multispectral satellite data to analyze plant cover and for devel-oping phenological models has been prosperous. However, a ground-based continued and detailed study of spectral measurements throughout the growing season would be useful by which not only spectral differences within and among seasons may be clarified but also the characterized wavelengths of crop species and variety may be identified. In the present study the reflectance spectra from 350 to 1100 nm were measured and the characterized wavelengths were recognized for the canopy cover of sweet potato (Ipomoea batatas cv. Tainung 57) grown in the field in 1995 and 1996. It was found the reflectance spectra of fresh canopy grown in different years were roughly similar, varied with environment and growth status. The ratio of reflected radiance in the UV region (740 nm) were fluctuated in 70-80%. Patterns of spectral irradiance and reflectance look similar to other green crops. The same 28 wavelengths were identified from the spectral radiance curves while only 6 characterized wavelengths were selected from reflectance spectra of sweet potato in both 1995 and 1996. Three wavelengths from spectral irradiance, 554, 688, and 754 nm, were further chosen for the calculations of vegetation indices. The vegetation index regress ion curves were curvilinear after planting, the increase of the curves stands for the building up of plant canopy and the curves fall off as plants aged.

關鍵字

季節變化、植冠光譜、甘藷、植被指數、特徵波長、反射比

Keywords

Seasonal change, Canopy spectrum, Sweet potato, Vegetation index, Characterized wavelength, Reflectance

附件檔名

華芸線上圖書館

N / A

備註說明

199803-3-1-13-28

Pages:

29-48

論文名稱

遙測影像中線型特徵物(道路)擷取之研究

Title

A Study of Linear Features (Roads) Extraction from Remote Sensing Imagery

作者

王則鴻 , 羅慶昌

Author

Tzer-HongWang , King-chang Lo

中文摘要

本文提出的自動道路擷取計劃乃先將遙測影像以特定的小波函數作小波轉換( Wavelet Transform ),增顯原始影像中的線型特徵物,並偵測得到各個像元的灰度梯度( Gray Gradient ) 及梯度方向 ( Gradient Direction )。隨後依照道路在影像之種種特性,應用上述之資料,自動的選擇路種( Seeds )。再應用道路在幾何( Geometric ) 及光度 ( Photometric ) 上的特性,組成泛道路模型( Generic Road Model ),並使用一些約制條件組成價值函數( Merit Function ),將泛道路模型具體化,作為擇取路段之條件。最後以自動選出的路種,依上述之條件開始搜尋可能的道路,再利用動態規劃( Dynamic Programming ) 求解出最佳的路段,擷取出影像中之道路。

Abstract

The topic of this research is about the scheme of extracting roads automatically which at first transform the remote sensing images with special wavelet function, and linear features of original images are detected to attain the gradient magnitude and direction of each pixel. Secondly, according to the some roads properties on the images and getting an application from above data, we make the rules to detect seeds of road automatically. The third, we have a generic road model which consists of some geometric and photometric properties of roads, and a merit function is formulated by some constraints which embodies a notion of the generic road model. A merit function is the conditions of selecting road segments. Last, the seeds of road are used in beginning to search for possible roads which are according to above conditions. Then, we take advantage of dynamic programming to extract the roads from image.

關鍵字

道路擷取、小波轉換、路種、動態規劃

Keywords

Road Extraction, Wavelet Transform, Seeds, Dynamic Programming

附件檔名

華芸線上圖書館

N / A

備註說明

199803-3-1-29-48

Pages:

49-69

論文名稱

特徵匹配於衛星影像套合之應用

Title

Satellite Image Registration Using Feature-Based Matching

作者

叢蕙滋 , 陳良健

Author

Hui-Tzu Tsung , Liang一Chien Chen

中文摘要

為提升衛星遙測科技之應用,多重遙測影像間整合之需求日殷。因此數位影像問幾何位置套疊關係之建立,於應用上即成為不可或缺的資料前處理步驟。本研究將特徵匹配之機制應用於影像套合,冀能提升其自動化之完整性。以影像中之均調區邊界為特徵,利用一形狀矩陣作為描述元,將區塊的形狀特徵網格化並進行特徵匹配,藉由一對應篩選法則濾除特徵匹配中錯誤之對應。再由這些正確的對應區塊,以其重心位置為套合控制點,進行起始轉換係數求解,可找出並建立套合影像與參考影像間起始的相對坐標轉換關係。以此為出發點,可提供進一步套合控制點加密時,匹配位置之預估資訊,完成精密影像套合。本研究之主體分為特徵匹配並建立起始對應關係與精密影像套合兩部份;在特徵匹配並建立起始對應關係部份,主要程序如下:(1) 利用形狀矩陣分別在套合影像與基準影像上對萃取出之影像區塊進行特徵描述,並進行相似性評估,產生對應候選;(2) 以區塊之重心連線的位向與幾何關係,濾除錯誤的對應候選,建立兩影像之起始對應關係。在精密影像套合部份,萃取參考影像上的特徵點,利用前面所得到之對應關係,提供套合影像上匹配之預估位置,進行區域匹配。再依所得匹配之點對結三角網,進行影像之局部套合。

Abstract

Data integration for multiple images is getting more important as more resource satel­lites become operational. Image registration is an indispensable preprocessing in integrating multi-source images. The automated densitification technique for registration control points is getting mature. However, the establishment of initial correspondence still needs efforts to increase the degree of automation. The objective of this investigation is to correspond the conjugate feature pattern those are extracted from a reference images and its counter­part i.e., a sensed image. The major components of the proposed scheme include: (1)quan­tatively describing the feature patches using shape matrix, (2)similarity assessment between patch pairs, (3)considering the topological and geometrical relationship between candidate patch controids to filter out unreliable matching (4)establishing initial transformation according to the reliable centroid pairs, and (5)applying fine matching to generate registration control points followed by a local transformation procedure.

關鍵字

影像套合、特徵、匹配、形狀矩陣

Keywords

Image Registration, Feature, Matching, Shape Matrix, (SM)

附件檔名

華芸線上圖書館

N / A

備註說明

199803-3-1-49-69

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