Search Results - "Annan, Richard Fiifi"

Assessment of HY-2A GM data by deriving the gravity field and bathymetry over the Gulf of Guinea by Wan, Xiaoyun, Annan, Richard Fiifi, Wang, Wenbin

“…Nine cycles of Haiyang-2A (HY-2A) IGDR (Interim Geophysical Data Record) data are used to derive gravity products over the Gulf of Guinea (15° W–5° E, 4° S–4°…”
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Recovering Marine Gravity Over the Gulf of Guinea From Multi-Satellite Sea Surface Heights by Annan, Richard Fiifi, Wan, Xiaoyun

“…A regional gravity field product, comprising vertical deflections and gravity anomalies, of the Gulf of Guinea (15°W to 5°E, 4°S to 4°N) has been developed…”
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Vertical Deflections and Gravity Disturbances Derived from HY-2A Data by Wan, Xiaoyun, Annan, Richard Fiifi, Jin, Shuanggen, Gong, Xiaoqi

“…The first Chinese altimetry satellite, Haiyang-2A (HY-2A), which was launched in 2011, has provided a large amount of sea surface heights which can be used to…”
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Evaluation of Four Global Bathymetry Models by Shipborne Depths Data by Hao, Ruijie, Wan, Xiaoyun, Wang, Yonglin, Fiifi Annan, Richard, Sui, Xiaohong

“…AbstractMore and more global digital bathymetric models (DBMs) have been developed using different kinds of data and have played a great role in navigation,…”
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Effects of Interferometric Radar Altimeter Errors on Marine Gravity Field Inversion by Wan, Xiaoyun, Jin, Shuanggen, Liu, Bo, Tian, Song, Kong, Weiya, Annan, Richard Fiifi

“…The traditional altimetry satellite, which is based on pulse-limited radar altimeter, only measures ocean surface heights along tracks; hence, leads to poorer…”
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Seafloor Density Contrast Derived From Gravity and Shipborne Depth Observations: A Case Study in a Local Area of Atlantic Ocean by Wan, Xiaoyun, Han, Weipeng, Ran, Jiangjun, Ma, Wenjie, Annan, Richard Fiifi, Li, Bing

“…Marine gravity data from altimetry satellites are often used to derive bathymetry; however, the seafloor density contrast must be known. Therefore, if the…”
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Analysis of limitations on recovery of gravity field based on satellite gravity gradient data by Xiaoyun Wan, Jinhai Yu, Lei Liang, Jiangjun Ran, Richard Fiifi Annan

“…Although satellite gravity gradient data plays a great role in determining short-wavelength part of static gravity field model, accuracy of the long-wavelength…”
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ACCURACY ASSESSMENT OF HEIGHTS OBTAINED FROM TOTAL STATION AND LEVEL INSTRUMENT USING TOTAL LEAST SQUARES AND ORDINARY LEAST SQUARES METHODS by Annan, Richard Fiifi, Ziggah, Yao Yevenyo, Ayer, John, Odutola, Christian Amans

“…Spirit levelling has been the traditional means of determining Reduced Levels (RL’s) of points by most surveyors.  The assertion that the level instrument is…”
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Recovering Bathymetry of the Gulf of Guinea Using Altimetry-Derived Gravity Field Products Combined via Convolutional Neural Network by Annan, Richard Fiifi, Wan, Xiaoyun

“…Traditional methods of bathymetry inversion from altimetry data often use gravity anomalies and/or vertical gravity anomaly gradients. These two gravity…”
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Enhanced Short-wavelength Marine Gravity Anomaly Using Depth Data by Hao, Ruijie, Wan, Xiaoyun, Annan, Richard Fiifi

“…Satellite altimetry cannot accurately derive the short-wavelength component of ocean gravity anomaly. Since the short-wavelength seabed topography affects the…”
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Mapping seafloor topography of gulf of Guinea using an adaptive meshed gravity-geologic method by Annan, Richard Fiifi, Wan, Xiaoyun

“…An adaptive mesh form of the gravity-geologic method, known as improved Gravity-Geologic Method (iGGM), was implemented on free-air gravity anomalies and…”
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Accuracy requirement for altimetry observations for bathymetry inversion using gravity anomaly and gravity gradients by Wang, Fei, Wan, Xiaoyun, Annan, Richard Fiifi

“…The gravity anomaly and vertical gravity gradient obtained from satellite altimetry observations play a great role in global bathymetry inversion. In order to…”
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Altimetry‐Derived Gravity Gradients Using Spectral Method and Their Performance in Bathymetry Inversion Using Back‐Propagation Neural Network by Wan, Xiaoyun, Annan, Richard Fiifi, Ziggah, Yao Yevenyo

“…Variations in bathymetry produce gravity gradients; therefore, gravity gradients should be suitable for inverting bathymetry. However, classical bathymetry…”
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Global marine gravity gradient tensor inverted from altimetry-derived deflections of the vertical: CUGB2023GRAD by Annan, Richard Fiifi, Wan, Xiaoyun, Hao, Ruijie, Wang, Fei

“…Geodetic applications of altimetry have largely been inversions of gravity anomaly. Previous studies of Earth's gravity gradient tensor mostly presented only…”
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