目前台灣沿海一些重要的水下管線，例如天然氣以及原油海底輸送管線等，可能因為颱風等天然因素，造成管線上方填方遭海流掏空而有遭受破壞之可能。對於提高水下施工技術能力以較佳地維護這些管線，實有必要對相關問題進行深入探討。
本研究目的在發展出一套可裝設在水下載具(Remote-control Operated Vehicle, ROV)上的影像流速測量系統之基礎部份。往後可利用ROV作為載台，以本研究之基礎作為測量海流速度或砂石速度的工具，再將現場所測量到的流速分佈狀況回傳工程人員，進而可規劃出埋設管線所用的砂石之最佳傾卸位置，亦可得知佈置ROV監控的最佳位置。
本研究主要採用質點軌跡測速儀(Particle Tracking Velocimetry, PTV)應用於移動質點之測速技術上，利用高照度氣體放電式光源(High Intensity Discharge, HID)與一般相機及攝影機拍攝質點位移距離。實驗以近似海洋中之質點與環境為條件，研究開發測速方式與資料分析技術。實驗共分成影像流速測量系統實驗與質點沉降實驗兩種。由結果可得知量測不確定之來源包括流場明亮度與流速會影響質點軌跡輪廓清晰度，以及攝像機之快門將會決定質點軌跡長短與否。而對於流場明亮度與攝相機感光度而言，若過多將會造成曝光過度，使質點受光源照射所散發反射範圍過大，進而造成統計結果正偏差。相反地，當流場過暗以及攝相機感光度過低時，將會使得上述反射範圍過小甚至不足，導致統計結果形成負偏差。

There are many underwater crude oil and nature gas pipelines on the ocean bottom around Taiwan. They are subjected to abrasive shear loading stemming from external force by nature phenomenon and human activities. In order to protect these pipelines, more research to advance underwater technology is needed.
A prototype of particle tracking velocimetry system integrated with particle recognition has been developed for installation on an ROV (Remote-control Operated Vehicle). The system can measure the velocity of underwater current and drifting sand from ROV’s, and then transmit the information of velocity through the cable. Therefore, it can help the planning for underwater engineering.
The measuring technique (PTV, Particle Tracking Velocimetry) uses a High Intensity Discharge (HID) light source, and CCD camera to capture successive images for particle displacement measurement. The present study uses material of tracing particle and experimental environment similar to underwater condition, including the development of image velocimetry system and particle subsided experiment. As can be discerned from the results, the range of experimental uncertainty varies due to the brightness, velocity of the flow fields, and the shutter of the camera. Extortionate magnitudes of the brightness of flow fields and high sensitivity of the CCD camera will overly illuminate particle resulting in positive error of velocity, and vice versa.

Adrain, R. M. (1991) Particle-imaging techniques for experimental fluid mechanics, Ann. Rev. Fluid Mech., Vol.23, pp.261-304.
Bruce, R. J., D. F. Young and T. H. Okiishi (1998) Fundamentals of Fluid Mechanics, John Wiley & Sons, NY.
D.H. Doh, T.G. Hwang, H.J. Jo, M. Tsubohura, B. Piao, S. Kuroda, T. Kobayashi, K. Tanaka, M. Takei (2007) Analysis of fluid－elastic-structure interactions in an impinging jet with a dynamic 3D-PTV and non-contact 6D-motion tracking system, Chemical Engineering Journal, Vol.130, pp.153-164.
Hellmich, Ch.; Scheiner, S.; Pichler, B.; Eberhardsteiner, J. (2006) Loading of soil-covered oil and gas pipelines due to adverse soil settlements－Proection against thermal dilation-induced wear, involving geosynthetics, Computers and Geotechnics, Vol.33, pp.371-380.
Khalitov, D.A. & Longmire, E.K., (2002) Simultaneous Two Phase PIV by two-parameter phase discrimination, Exp. In Fluids, Vol.32, pp.252-268.
Kiger, K. T. and C. Pan, (2002) Suspension and turbulence modification effects of solid particulates on a horizontal turbulent channel flow, Journal of Turbulence. Vol.3, No.19, pp.1-21.
Kitagawa A, Hagiwara Y, Kouda T (2007) PTV investigation of phase interaction in dispersed liquid-liquid two-phase turbulent swirling flow, Exp. in Fluids, Vol.42, pp.871-880.
Raffel, M.; Willert, C.E.; Kompenhans, J. (1998) Particle Image Velocimetry, Springer, Berlin, p.7.
Shen L, Song X, Murai Y, Iguchi M, Yamamoto F (2001) Velocity and size measurement of falling particles with fuzzy PTV, Flow Measurement and Instrumentation, Vol.12, pp.191-199.
You C, Zhao H, Qi H, Xu X (2004) Simultaneous measurement of velocities and size distribution of fine atmospheric aerosols based on image processing and PTV techniques, Atmospheric Environment, Vol.39, pp.3015-3021.
Westerweel, J. (1997) Fundamentals of digital particle image velocimetry, Meas. Sci. Technol, Vol.8, pp.1379-1392.
Willert, C.E.; Gharib, M. (1991) Digital particle image velocimetry, Exp. in Fluids, Vol.10, pp.181-193.

吳成柯、程湘君、戴善榮、雲立實，數位影像處理，儒林圖書公司，台北市，1993。
林仲芬，影像辨認技術(第二版)，全華科技圖書股份有限公司，台北市，1995。
葉翊霳，Adobe Phoshop6影像聖堂，上奇科技股份有限公司，台北市，2000。
馬秀蘭、吳德邦，統計學，新文京開發出版股份有限公司，台北市，2002。
洪維恩，Matlab7程式設計，旗標出版股份有限公司，台北市，2007。

【網站】
1. ALEC ELECTRONICS 公司
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2. M-Space 論壇
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3. TSI 公司
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4. 八里污水處理場
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Mar. 2008
5. 中山科學研究院
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6. 日昇無線器材有限公司
http://www.sunham.com.tw/, 24 Sept. 2007
7. 尖端科技軍武論壇
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8. 亞太港灣工程有限公司
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9. 高琇芬, 耗資200 萬 國內首發表潛航器, 自由時報新聞,
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cle&NewsType=twapple&Loc=TP&showdate=20060816&Sec_ID=5
&Art_ID=2821038, 21 Apr. 2008
10. 樊劍萍, 阿拉斯加油管腐蝕英國石油公司招致強烈抨擊, 法新社
新聞, http://tw.news.yahoo.com/article/url/d/a/060809/19/24d4.html,
29 Jan. 2008
11. 數位蘋果網
http://www.fuji.com.tw/dsc.asp?id=12, 16 Mar. 2008