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analysis of the common model error on velocity field under Colored noise model by GPS and InSAR: A case study in the Nepal and everest region

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Geodesy and Geodynamics 2022年第4期13卷 399-414页

作者： Wei Xu Gang Chen Kaihua Ding Defang Yang Yanfa Si Xiaoying Yang Qinghai Remote Sensing Center for Natural Resources Xining 810000China College of Marine Science and Technology China University of GeosciencesWuhan 430074China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

The accuracy of the velocity field will be affected by the noise model and common mode errors through GPS time series *** order to analyze the influence of these two factors on the accuracy of the velocity field,two kinds of data are used,including the three-year observation from 20 permanent GPS stations with high spatial correlation in the Everest,which is about 650 km from north to south and 1068 km from east to west,and three-year 80 ascending images and 141 descending images from sentinel-1A,which are processed by GAMIT/GLOBK software and Small Baseline Subset-Interferometric Synthetic Aperture Radar method(SBAS-InSAR),*** vertical deformation rate is solved by time series analysis through a self-made adaptive *** the analysis,the linear change rate,period,half period coefficient,and residual sequence of all stations are solved by using James *** periodic *** noise type of residual sequence is analyzed by the power spectrum *** spatio-temporal correlated noise,Common Mode Error(CME),is extracted by the Principal Component analysis(PCA)and Karhunen-Loeve(KLE)*** results show that noises can be best described by“flicker noise+white noise”*** the removal of CME,the R^(2) estimates of all stations are above 0.8,with RMS value of velocity field decreasing from 1.428 mm/yr to 1.062 mm/yr and 1.063 mm/yr to 0.815 mm/yr,in N and E directions,respectively,indicating that the influence of CME can't be ignored in the extraction of the high-precision velocity field in the Nepal and Everest region.

关键词： GPS time analysis SBAS-InSAR power spectrum analysis PCA KLE CME

CORRELATION BETWEEN ASO AND AAO

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Journal of Hydrodynamics 2004年第5期16卷 544-547页

作者： LIUNa ZHANGQing-hua CHENHong-xia KeyLaboratoryofMarineScienceandNumericalmodeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China CollegeofPhysicalandEnvironmentOceanography OceanUniversityofChinaQingdao266003China

Using a 34 years database consisting of sea level pressure and sea iceconcentration, the relationship between Antarctic Oscillation (AAO) and Antarctic Sea-iceOscillation (ASO) was investigated. Firstly, Empirical Orthogonal Function (EOF) analysis depictsthe spatial variability of AAO and ASO and Antarctic Sea-ice Oscillation Index (ASOI) was definedfor the first time. Secondly, power spectrum and head-lag correlation analysis show that ASO and AAOhave the same periods of quasi-three years, quasi-one year and quasi-half a year. Corresponding toAAO, ASO has an evident anti-oscillation after one and half a year.

关键词： ASO AAO EOF power spectrum analysis correlation analysis

Interpretations of gravity and Songliao Basin with Wavelet magnetic anomalies in the Multi-scale Decomposition

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Frontiers of Earth Science 2015年第3期9卷 427-436页

作者： Changbo LI Liangshu WANG Bin SUN Runhai FENG Yongjing WU School of Earth Sciences and Engineering Nanjing University Nanjing 210046 China Nanjing Institute of Geology and Mineral Resources Nanjing 210016 China

In this paper, we introduce the method of Wavelet Multi-scale Decomposition （WMD） combined with power spectrum analysis （PSA） for the separation of regional gravity and magnetic anomalies. The Songliao Basin is situated between the Siberian Plate and the North China Plate, and its main structural trend of gravity and magnetic anomaly fields is NNE. The study area shows a significant feature of deep collage-type construction. According to the feature of gravity field, the region was divided into five sub-regions. The gravity and magnetic fields of the Songliao Basin were separated using WMD with a 4th order separation. The apparent depth of anomalies in each order was determined by Logarithmic PSA. Then, the shallow high-frequency anomalies were removed and the 2nd-4th order wavelet detail anomalies were used to study the basin＇s major faults. Twenty-six faults within the basement were recognized. The 4th order wavelet approximate anomalies were used for the inversion of the Moho discontinuity and the Curie isothermal surface.

关键词： gravity and magnetic anomalies SongliaoBasin deep structure and geodynamics Wavelet Multi-scale Decomposition power spectrum analysis

ASSESSMENT OF THE POEM2 MODEL FOR SIMULATING TROPICAL INTRASEASONAL OSCILLATION

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Journal of Tropical Meteorology 2018年第3期24卷 323-333页

作者： WANG Kuo MA Hao LI Juan GU Bo-hui WU Hao Zhejiang Climate Center Hangzhou 310017 China College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 China International Pacific Research Center University of Hawaii at ManoaHonolulu 96822 USA Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Earth System Modeling CenterNanjing University of Information Science and TechnologyNanjing 210044 China Hu'nan Climate Center Changsha 410118 China

The intraseasonal oscillation(ISO)of the atmosphere is closely related to weather and climate systems and is also an important aspect of extended numerical weather forecast *** phenomenon is significant in tropical regions and is one of the key indices for assessing the simulation capability of a climate *** better evaluate numerical model simulations of the tropical ISO using the 10-year historic data calculated by the POEM2 climate system model developed by the University of Hawaii in the U.S.,we utilized the methods of variance and power spectral analysis to compare and assess the simulation ability of this model for the ISO in tropical *** results showed that the simulated variance results for the 850 h Pa zonal wind and outgoing long-wave radiation(OLR)by POEM2 are overall consistent with the observed distribution pattern,and the simulated variance is relatively larger than the observed in the North Indian Ocean and West Pacific *** respect to the summer model,the winter model can better simulate the eastward propagation motion of the Madden-Julian oscillation(MJO)and the 850 h Pa zonal *** comparison,the summer model can better simulate the northward propagation motion of MJO and atmospheric precipitation than the winter *** eastward propagation speed of the simulated MJO signal is faster in the model than in the observation,and the high frequency region for the power spectra of meteorological element anomalies are concentrated in wavenumber 2-3 in the simulation and in wavenumber 1-2 in the *** multivariate combined empirical orthogonal function(EOF)results showed that this model can simulate the relationship between high-low level wind distributions and precipitation over the East Indian Ocean and the West Pacific,but the simulated signal is weaker than the *** lagging correlation of time coefficients between the first two EOFs from observation and simulation shows a similar ***,these resu

关键词： model diagnostics power spectrum analysis POEM2 model MJO

Implications on Gravity Anomaly Measurements Associated with Different Lithologies in Turkana South Subcounty

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Journal of Geoscience and Environment Protection 2023年第1期11卷 79-118页

作者： Daniel Mogaka Nyaberi Department of Environmental Earth Sciences University of Eldoret Uasin Gishu Kenya

The use of gravity data has demonstrated capability for monitoring lithological changes on a large scale as a consequence of differentiating basement and sedimentary of buried valleys. Gravity anomalies are associated with lateral contrasts in density and therefore deformation by faulting or folding will be manifested if accompanied by lateral density changes, otherwise, the vice versa is true. The study’s objective is to evaluate the effectiveness of gravity method in establishing different lithologies in an area. The study has revealed that regional anomaly gravity map presents high anomalies in the Northern region in the NW-SE trend and low anomalies in the southern trend in NW-SE, while the residual anomaly gravity map shows different trends for the low and high gravity anomalies. The gravity anomalies are well interpreted in line with the lithologies of the study area rather than the deformation of the same lithologies. There are observed high values of gravity anomaly values (ranging from -880.2 to -501.2 g.u.) where there are eolian unconsolidated rocks overlying the basement compared to low gravity anomaly values (ranging from -1338.9 to -1088.7 g.u.) where the andesites, trachytes and phonolites overly the basement. The different regional gravity anomalies relate well with different rock densities in the study area along the line profile for radially averaged power spectrum. The gravity highs are noted in the eastern point and are associated with andesites, trachytes, basalts and igneous rocks, while the gravity lows are associated with sandstone, greywacke, arkose, and eolian unconsolidated rock. The utilization of the information from the power spectrum analysis demonstrates that the depth to the deepest basement rock is 12.8 km which is in the eastern flank, while the shallowest to the basement of 1.1 km to the western flank.

关键词： Regional Gravity Anomalies power spectrum analysis Density Contrasts Lithologies

Research on magnetic levitation absolute vibration measurement method in vehicles

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Instrumentation 2014年第2期1卷 38-49页

作者： JIANG Dong SHAN Yi WANG Deyu YANG Jiaxiang College of Electrical&Electronic Engineering Harbin University of Science and TechnologyHarbin 150080C仇加a

This paper presents a design for a magnetic levitation absolute- vibration test system which can be used by vehicles to measure the road surface roughness. The relationship between the vibration test system output voltage and measured speed of the object was obtained through testing,the power spectrum of the measured signal was obtained by virtual instrument analysis,the vibration waveforms of the vehicle over gentle and steep slopes were measured respectively and the road surface roughness was obtained by waveform analysis. Data was saved where the waveforms exceeded threshold. Finally,the steep slope was located using a GPS system. Experimental results show that the magnetic levitation absolute- vibration measurement method has characteristics of high sensitivity and a wide frequency range. This lays the foundation for research into multi- dimensional vibration measurements through magnetic levitation vibration test systems in vehicles.

关键词： magnetic levitation speed sensor flatness power spectrum analysis

EEG analysis of Drivers under Emergency Situations

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EEG Analysis of Drivers under Emergency Situations

High-order Spectral analysis for Micro-Seismic Signal

2012 International Conference on Affective Computing and Intelligent Interaction(ICACII 2012)

作者： Luzheng Bi 1 a Zhi Wang 1 b and Xin-an Fan 1 c 1 School of Mechanical Engineering Beijing Institute of Technology South 5 Zhongguancun Street Haidian District 100081 Beijing China

This paper investigates the EEG characteristics of drivers’ response to pedestrian sudden occurrence,as an example of emergency situations,to explore the feasibility of using the EEG of drivers to develop a method to address driver possible slow response for avoiding traffic accidents or reducing deaths and *** drivers attended the experiment in a driving simulator with virtual driving environments,along with EEG signals being collected at twenty standard locations on the *** power spectrum analysis was applied to capture the changes of *** results suggest that the power spectrum of the EEG of drivers under pedestrian sudden occurrence are significantly different with those of drivers’ response to normal situations at the locations:P3,P4,P7,P8,PZ,O1,O2,OZ,T7,and T8,which can be used to help select associated information of EEG as input features of the detection model of pedestrian sudden occurrence.

关键词： EEG emergency situations driver response power spectrum analysis detection model.

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High-order Spectral Analysis for Micro-Seismic Signal