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收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

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🏛️國立陽明交通大學機構典藏

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    台灣地區高程系統及其變遷之研究---子計畫四： 衛星及重力法台灣高程系統
    (1995)
    黃金維
    ;
    Hwang Chein-Way
    ;
    國立交通大學土木工程研究所
    高程系統通常以平均海水面為參考面.然而 平均海水面由於受到海流、氣候之影響而產生 變遷,較理想的參考面為大地水準面(Geoid).本計 畫擬使用重力異常、地形、衛星測高資料及一 地球位模式求算局部、地心座標系統的大地起 伏.一適合在高山地區的理論模式將是重點.另 配合1GS在台灣的測站,可利用GPS求得基隆平均 海水面相對於橢球的高度.此點的橢球高與大 地起伏可用以求得基隆海水面與大地水準面的分離量.此絕對的海水變遷量可與世界其他相 同資料結合而研究全球變遷的問題,衛星測高 資料亦可獨立地或與上述資料結合求得基隆平 均海水位的變遷.
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    台灣地區高程系統及其變遷之研究---子計畫四：衛星及重 力法台灣高程系
    (1996)
    黃金維
    ;
    國立交通大學土木工程研究所
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    台灣高程系統及其變遷之研究---子計畫IV：衛星及重力法台灣高程系統
    (1997)
    黃金維
    ;
    Hwang Chein-Way
    ;
    交通大學土木工程學系
    高程系統通常以平均海水面為參考面。然而平均海水面由於受到海流、氣候之影響而產生變遷，較理想的參考面為大地水準面 (geoid)。本計劃擬使用重力異常、地形、衛星測高資料及一地球位模式求算局部、地心座標系統的大地起伏。一適用在高山地區的理論模式將是重點。另配合IGS在台灣的測站，可利用GPS求得基隆平均海水面相對於橢球的高度。此點的橢球高與大地起伏可用以求得基隆海水面與大地水準面的分離量。此絕對的海水變遷量可與世界其他相同資料結合而研究全球變遷的問題，衛星測高資料亦可獨立地或與上述資料結合求得基隆平均海水位的變遷。
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    Topography-Assisted downward Continuation of Airborne Gravity: An Application for Geoid Determination in Taiwan
    (2010-08-01)
    Hsiao, Yu-Shen
    ;
    Hwang, Cheinway
    ;
    土木工程學系
    ;
    Department of Civil Engineering
    We investigated the Fourier transform-based downward continuation (DWC) of airborne gravity anomalies around Taiwan assisted by topographic information. The topographic data are from the latest collections of elevations and ocean depths. The DWC employs a remove-compute-restore (RCR) procedure in which the topography is removed prior to computation and then restored to achieve stable solutions. The topographic gravity effect is evaluated point-wise using the Gaussian quadrature. A Gaussian filter with an optimal smoothing parameter reduces the noise-amplifying effect of DWC. Use of topography in DWC leads to improvements of 3 to 6 mgal of gravity on land. Surface and downward continued gravity anomalies are used to determine geoidal heights by least squares collocation (LSC) in a similar RCR procedure through the same topographic data. The accuracy of the geoidal heights at Taiwan's first-order leveling benchmarks is improved by 1 to 2 cm due to inclusion of downward continued airborne gravity.
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    Analysis of Alabama Airborne Gravity at Three Altitudes: Expected Accuracy and Spatial Resolution from a Future Tibetan Airborne Gravity Survey
    (2013-08-01)
    Huang, Chi-Hsun
    ;
    Hwang, Cheinway
    ;
    Hsiao, Yu-Shen
    ;
    Wang, Yan Ming
    ;
    Roman, Daniel R.
    In situ airborne gravity data at altitudes of 11, 6.3, and 1.7 km over a smooth area of Alabama are used to assess gravity accuracy and errors in upward and downward continuations. Analysis of the Alabama free-air anomaly gravity data at crossover points at the three altitudes suggests 1 - 2 mgal accuracy for the dataset. Gravity data at each altitude are then expanded into local 3D Fourier series, to prepare for continuation. This Fourier representation results in continuation errors at few-mgal level in Alabama, even in the extreme case of downward continuation from 11 km to sea level. The result in Alabama inspires an airborne gravity survey over the rough, inaccessible terrain of Tibet. Similar investigations as in Alabama are made in Tibet using EGM08-derived airborne gravity data at flight altitudes of 10, 5, and 0 km. Bouguer anomalies at the 10-km altitude preserve the major tectonic features of Tibet. Downward continuation errors increase with terrain roughness, but the survey can enhance local tectonic features. This study highlights the value of a future Tibetan airborne gravity survey and points out the expected gravity accuracy and spatial resolution from this survey.