ENGLISH

24卷/2期

24卷/2期

華藝線上圖書館

Pages:

79-87

論文名稱

整合空間資訊技術與土地利用迴歸模式推估高屏空品區細懸浮微粒之時空分布

Title

Integrate Geospaital Information Technologies and Land-use Regression to Estimate the Spatial-temporal Variability of Fine Particulate Matter in Kaohsiung-Pingtung Air Quality Zone

作者

曾芷琳、蕭雅萍、曾于庭、陳穆貞、龍世俊、吳治達

Author

Chih-Lin Zeng, Ya-Ping Hsio, Yu-Ting Zeng, Mu-Jean Chen, Shih-Chun Candice, Chih-Da Wuo

中文摘要

近年來細懸浮微粒(Fine Particulate Matters, PM2.5)對健康的影響日益受重視。台灣於2006 年起將PM2.5 列為空氣品質之監測指標之一,然而受限於台灣全島之測站數量稀少且分布不均,加上區域內汙染排放 源類型多元且複雜,故如何有效推估污染物濃度之時空變異,實為當前環境流行病學的重要課題之一。 基於此,本研究選擇台灣空污問題最為嚴重之高屏空氣品質管理區為試區,利用區內15 個環保署空氣品 質監測站於2006 年至2012 年之年平均PM2.5 濃度監測資料為材料,透過地理資源系統以及遙感探測等空 間資訊技術獲取測站周邊之土地利用資訊,進而建立土地利用迴歸模式(Land Use Regression Model, LUR), 以推估高屏空品區PM2.5 之時空分布。研究結果指出,最終所建立之土地利用迴歸模式之R2、校正後 R2 以及RMSE 分別為0.82、0.82 以及3.81μg/m3;選入之變數包含與工業區之距離、方圓3,000 m 內NDVI 最小值、氣溫以及方圓1,500 m 內稻作面積,其中又以與工業區之距離為最主要因子(partial R2=0.76);在 模式驗證方面,留一驗證與外部資料驗證之R2 分別為0.81 及0.67,整體來說模式之推估能力尚算穩定; 最後利用所建模式推估高屏空品區之PM2.5 濃度分布,結果顯示,研究期間PM2.5 濃度呈略微下降趨勢, 並且高濃度地區多分布於高屏沿海之都會區,尤以高雄市區之汙染程度最為嚴重。

Abstract

Along with industrialization and urbanization, the exploitation of natural resources makes emissions of air pollutants increases. Fine Particulate Matter (PM2.5) is one of the pollutants which affect human health and has been attracting attention in recent years. Observations from the limited number of monitoring sites are not capable to depict the spatial concentration pattern of PM2.5. Diverse culture-specific emission contributors distributed in communities raise the difficulty of emission classification as well. This study selected Kaohsiung-Pingtung Air Quality Zone (Kao-Ping AQZ) as the study area. Annual average PM2.5 level was calculated based on the on-site observations from 15 EAP monitoring stations during 2006 to 2012. Land-use allocation surrounding the monitoring sites were obtained from GIS databases. A Land Use Regression (LUR) model then developed to estimate the spatial-temporal variability of PM2.5 concentrations of Kao-Ping AQZ. The overall model R2, adjusted R2, and RMSE was 0.82, 0.82, and 3.81µg/m3, respectively. Several land-use and environmental variables were selected as important predictor variables, including distance to the nearest industrial park, minimum of NDVI within 3000m buffer range, temperature, and area of farm within 1500m buffer range. With the partial R2 of 0.76, distance to the nearest industrial park was the dominant variable in the developed model. The results of model validation again confirmed the model performance while the R2 from cross validation and external data verification was 0.81 and 0.67, respectively. The predictions of PM2.5 variability based on the developed LUR model showed a slightly decreasing trend during the study period while coastal metropolitan areas were always the higher pollutant areas.

關鍵字

細懸浮微粒、空間資訊技術、土地利用迴歸模式、高屏空品區、時空分布

Keywords

Fine Particulate Matter (PM2.5), Geospaital Information Technologies, Land Use Regression, Kaohsiung-Pingtung Air Quality Zone, Spatial-temporal Variability

附件檔名

華芸線上圖書館

http://www.airitilibrary.com/Publication/Index?DocID=10218661-201906-201906270002-201906270002-79-87

備註說明

N / A

Pages:

89-110

論文名稱

利用衛星影像以有理函數物像對應解算水位面高程及水下物點三維坐標

Title

Simultaneously Determining Water Surface and Underwater Object Points based on Rational Function Model by Using Satellite Images

作者

張雅博、趙鍵哲

Author

Ya-Po Chang, Jen-Jer Jaw

中文摘要

現今衛星影像大多利用有理函數模式進行物像對應,但是當衛星攝影取像對象為水下可視場景時,成像光線會因為折射效應而產生偏移,此時衛星影像帶有的有理函數係數並無法正確描述雙介質的物像對應關係。為此,本研究提出一調變模式,在有理函數模式下仿擬成像路徑,並考慮折射效應,建構帶有約制的廣義最小二乘平差模式進行水位面高程及水下物點三維坐標解算。基於幾何本質,受到折射效應的成像路徑,在水位面為完全未知的情況下,水下折射向量會隨著水位面位置的迭代解算而改變,此時水位面及水下物點定位具有很大的可接受解算範圍,無法獲得良好的定位成效。因此,本文除揭櫫此物像對應的特質外,並探討倘若具有額外物空間之觀測值,例如:水位面高程、高程控制點、全控點及水深等,其如何助益於水位面及水下物點的定位解算。除此之外,聯合多點解算之效益也一併納入考量。實驗資料部分,則以模擬資料與實際資料驗證所提模式之適用性並完成成果之定性及定量分析。成果上,水位面品質為此定位模式之關鍵,故須採用可資使用的物空間約制來進行,在絕對條件具有良好品質時,以水位面約制效果最佳;另一方面,高品質之水深資訊約制解算可獲致水位面定位品質達1~2 pixels,聯合多點位水深約制效果又會更佳。除此之外,在高品質水深約制模式下,水下物點高程分量品質更勝於水位面完全已知時之解算成效。

Abstract

Nowadays, most satellite imagery vendors offer rational polynomial coefficients (RPCs) to users for processing geometric information. Although known RPCs in rational function model (RFM) would give explicit object-to-image correspondence, the physical meaning of the parameters is hard to be interpreted. Especially, when faced with underwater object points, the object-to-image correspondence cannot be directly realized by these RPCs due to the refraction effect. To cope with this situation, this study proposes an alternative way in the imaging rays under RFM and refraction effect to determine both the water surface and underwater object points. A generalized least-squares adjustment with constraints is developed to well handle functional and stochastic models. To its essence provided that the water surface is totally unknown, the refraction vectors under the water varying with estimated water surface through each iteration results in a weak geometry and leads to unstable solutions. In addition to revealing the characteristics of aforementioned object-to-image correspondence, this study explores how the underwater object point and water surface determination would benefit from the prior observations of water surface, vertical control point, full control point, and even water depth. The effect of using multiple points is also investigated in this study. In experiment part, this study uses not only simulation data but also real satellite imagery to verify the feasibility of the proposed model. And it can be summarized that the quality of water surface, either through priori information or derived from control information, is crucial to the positioning performance of underwater object points. The accuracy of water depth better than 2m, under employed satellite imagery, would supply water surface with 1-2 pixels positioning quality, and even bring about superior underwater object point coordinates as compared to when they are to be determined through perfect water surface.

關鍵字

有理函數模式、折射效應、水下物點、水位面高程、約制

Keywords

Rational function model, Refraction effect, Underwater object points, Water surface, Constraints

附件檔名

華芸線上圖書館

http://www.airitilibrary.com/Publication/Index?DocID=10218661-201906-201906270002-201906270002-89-110

備註說明

N / A

Pages:

111-121

論文名稱

以解算連續像對相對方位參數之單眼視覺里程計

Title

Model by Using Satellite Images Monocular Visual Odometry by Solving Relative Orientation Parameters of Consecutive Image Pairs

作者

林照捷、曾義星

Author

Chao-Chieh Lin, Yi-Hsing Tseng

中文摘要

視覺里程計是透過分析連續像對讓機器人可以在陌生環境中持續且自動的定位。無論是在攝影測量或是電腦視覺皆存在該定位技術,但使用方法和目的有些不同,因此本研究結合這兩種方法完成單眼視覺里程計。首先提出合適的匹配策略及自動求解相對方位的方法,以第一張影像的透視中心為原點,且物空間座標系三軸和第一台相機座標系三軸相同,將相對方位依序疊加,獲得連續像對的連續相對方位。但相對方位的誤差會持續累積而產生路徑飄移,因此本研究提出針對相對方位的網型平差解決問題。實驗成果顯示本研究可以重建出合理的相機路徑和周圍的稀疏物點,且透過網型平差,可以有效地更新影像外方位參數及降低誤點偏差量。

Abstract

Through analyzing consecutive image pairs, the robotic can localize itself autonomously and continuously in an unknown environment without any human input, and it is known as Visual Odometry. Localization can be achieved in photogrammetry and computer vision, but the methods and objectives are little different. Consequently, combinable methods are used to reconstruct the camera path in this study. Firstly, an appropriate matching strategy and an automatic method for solving relative orientation parameters (ROPs) are applied in this study. Secondly, coherent relative orientation of consecutive image pair can be determined by stacking individual ROPs. Since the localization of consecutive images is incremental, the errors are accumulated over time. In this study, a preliminary study of network adjustment of ROPs is proposed to suppress the accumulated error in the navigation. In the tests, results show the estimated camera path and reconstructed 3D object points are reasonable, and the features in reconstruction can be recognized clearly. Comparing estimated camera path before and after with actual camera path, the accumulated errors is reduced significantly. Furthermore, the deviation of object points derived from different image pairs are decreasing. In conclusion, the network adjustment in this study is effective to reduce the accumulated errors of the camera path.

關鍵字

單眼視覺里程計、相對方位、累積誤差

Keywords

Monocular Visual Odometry, Relative Orientation, Accumulated Errors

附件檔名

華芸線上圖書館

http://www.airitilibrary.com/Publication/Index?DocID=10218661-201906-201906270002-201906270002-111-121

備註說明

N / A

Pages:

123-133

論文名稱

高精地圖輔助車載衛星定位偵測與改善都市多路徑效應及NLOS誤差影響

Title

High Definition Maps Aided to Detect and Improve Vehicle Satellite Positioning with Effect of Multipath and NLOS Reception in Urban Area

作者

徐珮晴、李育華、江凱偉

Author

Pei-Ching-Hsu, Yu-Hua Li, Kai-Wei Chiang

中文摘要

隨著智慧運輸系統的發展,精確的位置資訊是實現自動駕駛車的核心議題之一。然而全球導航衛星系統在都市地區會因為密集複雜的大樓造成多路徑效應及非直線視距觀測(Non-Line-of-Sight, NLOS)現象,使定位精度不佳。本研究使用車載整合式定位定向系統建立模擬之高精地圖(HD Maps)作為參考資訊,用以偵測及剔除上述錯誤的定位解,同時反饋至高程約制系統提升三維精度。實驗使用商用接收機觀測全球導航衛星系統單頻電碼進行單點定位,成果顯示由高精地圖輔助可提升定位精度約66%,其中高程誤差近乎完全被消除。本研究可作為高精地圖導航應用之雛型,讓自動駕駛在都市更加穩健可行。

Abstract

With the development of Intelligent Transport System (ITS), the precise position is one of the primary cores to achieve the autonomous driving vehicles. However, Global Navigation Satellite System (GNSS) would be affected in poor accuracy by changes in surrounding obstacles, which is well-known as the multipath interference and Non-Line-of-Sight (NLOS) reception in urban environments. This study uses the integrated vehicle navigation system to establish High Definition maps (HD Maps) as reference information to detect the positioning errors due to multipath or NLOS reception. Moreover, the correction can feedback to the navigation process by height constraints system. The experiment applies commercial satellite receiver to observe single-frequency GPS code for Single-Point Positioning (SPP) calculation. The results show that with the HD Maps aided, the positioning accuracy improves by about 66%, which the height error is almost mitigated. This research is the prototype of HD Maps aided navigation application, which can make the autonomous driving positioning system more robust and feasible in urban area.

關鍵字

多路徑效應、非直線視距觀測量、高精地圖、全球導航衛星系統、都市地區

Keywords

Multipath interference, Non-line-of-sight reception, High Definition Maps, Global Navigation Satellite System, Urban area

附件檔名

華芸線上圖書館

http://www.airitilibrary.com/Publication/Index?DocID=10218661-201906-201906270002-201906270002-123-133

備註說明

N / A

Pages:

135-136

論文名稱

運用無人飛行載具吊掛簡易聲納測量水體參數

Title

Using UAV with Low-cost Sonar to Measure Parameters of Ponds

作者

洪一展、萬泓顯、蔡沛芸、廖婉婷、曾國欣

Author

Yi-Chan Hung, Hung-Hsien Wan, Pei-Yun Tsai, Wan-Ting Liao, Kuo-Hsin Tseng

中文摘要

傳統上對於內陸水體多利用單音束與多音束測深儀量測水深,可得剖面深度測線進而產出水底地形,但若應用於小型水域,船隻不便行駛且成本將顯著提升,因此載具的機動性逐漸成為研究目標。近年因消費級無人機興起,運用其高機動性可取代人們進入不易到達之區域進行觀測,對於空間中的點狀測量提供了一種新型作業平臺。為了解小型水體(如埤塘)的水深並計算水量變化,本研究結合無人機、智慧型手機與小型簡易聲納,於水面進行點狀水深測量,後續使用空間內插擬合埤塘水底地形。於桃園四口埤塘測量成果顯示,水深量測內部精度(連續觀測之標準差)於每口平均值可小於0.13 m,若與水務局早期實測資料比較,經水位調整後深度差的標準差為0.15 m,另面積誤差為3.2%–8.9%。本研究歸納出在缺乏船載實測資料時,本系統可於低時間與人力成本考量下,在水域深度介於六十公分至數公尺的水體進行深度與量體估計。

Abstract

Conventional methods used to retrieve water depth for inland waterbodies rely on single-beam or multi-beam echo sounders, which sample depths along multiple survey lines and produce bathymetry through grid interpolation. However, for small or shallow waters where ships are not easy to navigate it would require other costly surveying strategies. Therefore, the maneuverability of sensor platform has been growing interest in related research fields. Reducing cost of commercial unmanned aerial vehicle (UAV) in recent years has facilitated its wide applications in geoinformatics. Owing to its high mobility, an innovative platform for point measurement is easily accessible. In order to understand water depths of small inland waterbodies and to calculate temporal changes of water volume, this study aims to combine an UAV, a smartphone, and a low-cost sonar to measure several ponds in Taoyuan. This integrated measuring system is operated over water surface to measure pointwise water depths for bathymetry mapping. The results show that an internal accuracy of water depth measurements (standard deviation of repeat observations) in four randomly chosen ponds of Taoyuan has achieved <0.13 meters. On the other hand, the root-mean-square of difference (RMSD) between depth measurements and historical data from Department of Water Resources in Taoyuan city (after appropriate water level adjustment) is 0.15 meters. Meanwhile, errors of area estimates are in a range of 3.2–8.9%. We conclude that in the absence of shipborne measurements, this method can sufficiently provide depth and volume estimation at low time/labor costs for small ponds whose depth is greater than 60 k.

關鍵字

無人機、簡易聲納、埤塘、水底地形

Keywords

Unmanned Aerial Vehicle, Sonar, Pond, Underwater Terrain

附件檔名

華芸線上圖書館

http://www.airitilibrary.com/Publication/Index?DocID=10218661-201906-201906270002-201906270002-135-146

備註說明

N / A

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