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Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The successful implementation of multi-generation gravity satellite missions has made significant progress in using gravity satellite observation data to monitor global mass changes. This has improved our understanding of large-scale material migration, global environmental changes in the Earth system, and facilitated research on critical environmental issues such as global sea level change monitoring, glacier melting, and groundwater extraction. Limitations in the accuracy and resolution of satellite instruments, along with factors such as modeling errors, result in global mass changes calculated using gravity satellite data being affected by noise patterns in the form of south-north stripes and signal leakage. While commonly used filtering and smoothing methods effectively mitigate the impact of south-north stripes noise, they exacerbate signal leakage problems. To address these issues and enhance the spatiotemporal resolution and accuracy of surface mass changes in the calculation of gravity satellite data, numerous scholars have developed a point-mass modeling approach based on Newton's law of universal gravitation. These methods establish a direct relationship between surface mass changes and perturbed motion of satellites, employing constraint matrices to tackle strip errors and ill-posed problems arising from downward continuation. This article examines the research progress of the point-mass modeling approach, provides a comprehensive overview of the fundamental theories and various methods employed, analyzes different strategies and characteristics of constraint matrices, and provides a concise summary of the post-processing methods associated with this approach. The comprehensive analysis presented in this article is intended to serve as a valuable reference for the future development and research of the point-mass modeling approach. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Technology Economics is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Continuous and dense global navigation satellite system (GNSS) observations of surface deformation can be used to recover regional terrestrial water storage (TWS) changes with high spatiotemporal resolution, which is of great significance for the study of regional water cycle and climate changes and has become a hot topic in the field of hydro-geodesy. This paper introduces the basic theory and inversion algorithms of the loading Green's function method and Slepian basis function method, and the stability and performance of these two methods in retrieving regional TWS changes by using GNSS surface deformations are evaluated. Meanwhile, the latest progress in using GNSS-derived TWS changes to study regional water cycles and extreme climate changes is reviewed. The existing problems and future development trends of the inversion of GNSS observations (e. g. refined GNSS data processing and joint inversion of multi-source data) are summarized and analyzed. It provides important insights into the use of GNSS observations to investigate regional TWS changes and related applications in hydro-geodesy. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Management & Technology Discussion is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geomatics & Information Science of Wuhan University is the property of Geomatics & Information Science of Wuhan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Science Research & Application is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hebei University of Science & Technology is the property of Hebei University of Science & Technology, Journal of Hebei University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kinematic acceleration estimated by GPS (Global Positioning System) is significant for airborne scalar gravimetry. Comparing with the conventional approach of DGPS (differential Global Positioning System), we introduce an alternative approach of the stand alone receiver, which is using time difference carrierphase observation between two successive epochs without the requirement of groundbase stations. In this approach, time series of high precision epoch wise displacements are estimated firstly, then a Taylor approximation differentiator with the consideration of actual gravity data is applied to obtain accelerations as well as velocities. Meanwhile, the effects of satellite orbits and clocks errors on acceleration estimation are analyzed carefully. The results show that the satellite clock products have significant impact on the acceleration determination, while it can be neglected for orbits errors. Then the performance of the proposed approach is validated using a flight test carried out in Shaanxi Province, China. Aircraft accelerations are determined using the proposed method, then are used to calculate the gravity disturbances. According to the comparison, the derived gravity disturbances show a very good consistency with those obtained from DGPS, and the difference is better than 1.0 mGal at the filtering period of 100 s. Furthermore, the recovered gravity disturbances along the survey lines are checked for internal consistency at the intersections, the RMS is 1.13 mGal consistently at the filtering period of 100 s. Finally, comparing with the measured ground gravity, the accuracy of the proposed method is basically consistent with the DGPS methods - , which indicates that it is feasible for airborne scalar gravimetry without ground base stations. [ABSTRACT FROM AUTHOR]

A static measurement experiment and an elevator-platform lest of GT-2A have been designed to determine the zero drift rate, resolving power and scale factor of the instrument. We have calculated the drift rate with the static continuous observations from GT-2A and a relative gravimeter, as well as the tidal gravity from solid tide model. Considering solid tide correction, the zero drift rate of GT-2A observations decreases from —6.5 μGal/h to —0.1 μGal/h, while the representative error caused by using the zero drift rate from calibration measurement decreases from 7.2 μGal/h to 1.1 μGal/h. Thus, we can see that the solid tide has great influence on the determination of zero drift rale. With these data, the ability for GT-2A to monitor solid tide can be tested. The results from frequency domain analysis shows that the tidal components whose amplitude exceeds 30 μGal can be seen in the amplitude-frequency diagram, which means the resolving power of GT-2A is about 30 μGal. The observations of GT-2A from the elevator-platform lest can be used to calculate the vertical gradient of gravity, which is then compared with the result measured by the relative gravimeter. Then the scale factor of the instrument has been determined to be —0.0034 + 0.011 6. [ABSTRACT FROM AUTHOR]

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Xinyang Normal University Natural Science Edition is the property of Journal of Xinyang Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the flexural isostasy model of the lithosphere, a 1°×1° model of lithospheric effective elastic thickness over the global seafloor was calculated by the Moving Window Admittance Technique (MWAT) method, using bathymetry and gravity anomalies derived from altimetry data. The results show that the lithospheric effective elastic thickness over the seafloor is generally small. About 70% of the seafloor has an effective elastic thickness of lower than 10 km, and 85.4% are lower than 15 km. The mean and standard deviation of effective elastic thickness is about 10 km and 6.7 km, respectively. The lithosphere with an effective elastic thickness larger than 20 km is mainly located in out rise of the trenches. The lithosphere over the mid-ocean ridge usually has effective elastic thickness of lower than 5km. The strength of lithosphere over the passive continental margin, such as the southern margin of the Australian continent, is also weak. The effective elastic thickness of lithosphere over the seamount area of the Pacific is about 10 to 20 km. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

食管癌的组织学类型主要以鳞状细胞癌为主，放射治疗是其重要的治疗手段之一。但部分患者对放射治疗不敏感或放射治疗后出现局部复发。“肿瘤干细胞”学说认为，肿瘤细胞中存在一类具有自我更新和多向分化能力并能产生异质性肿瘤细胞的细胞，即肿瘤干细胞。食管癌细胞中亦存在此类干细胞。有研究认为，食管癌干细胞的存在是导致食管癌放射治疗不敏感的一个重要原因，其机制可能与细胞周期再分布、干细胞基因高表达及信号转导通路异常有关。目前针对食管癌干细胞放射敏感性的研究越来越受到关注。 [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A semi-analytical (SA) approach is proposed to recover a gravity field model from the GOCE tensor invariant observations. The SA approach is more efficient than the least-squares method, and could provide the posterior variance of estimated coefficients. The formulas for gravity field model determination from tensor invariant observations based on SA approach were derived and a corresponding procedure for estimation of the satellite gravity model from satellite gravity gradient observations are described. Testing results from the simulated error free observations along the circular orbit with the inclination 89.5° show that applying the SA approach to process tensor invariant observations is theoretically rigorous. Using the simulated observations with or without errors in gradiometer reference frame (GRF) along the one repeat cycle GOCE real orbit, we recovered the gravity field models from the I2 and Vzz components respectively. Numerical analysis results show that the solution from I2 was slightly better than the one from Vzz component, which verified the feasibility of the method. [ABSTRACT FROM AUTHOR]

In this paper, a 1'X1' bathymetry model over China Sea and its adjacent areas was formed combining ship soundings, gravity anomalies and vertical gravity gradient anomalies. The ship soundings were used for constraining bathymetry at wavelengths longer than 200 km. The vertical gravity gradient anomalies were used for predicting bathymetry at 100 ~ 200 km wavelength. The gravity anomalies were used for predicting bathymetry at wavelength shorter than 100 km. Compared to ship soundings, the accuracy of the predicted model for the South China Sea and Philippine Sea was evaluated. The results show that the accuracy of the model is better than the ETOPO1, GEBCO and DTU10. In South China Sea, the accuracy of predicted model is consistent with the latest V15. 1 model from SIO. In Philippine Sea, as compared to V15. 1, the accuracy of the model increased by about 8.2%. [ABSTRACT FROM AUTHOR]