Geomagnetic observatory data are crucial for all branches of geophysics because they can contribute to earthquake research by detecting anomalies in the Earth’s magnetic field.Recently,data records from the Misallat(...Geomagnetic observatory data are crucial for all branches of geophysics because they can contribute to earthquake research by detecting anomalies in the Earth’s magnetic field.Recently,data records from the Misallat(MLT)and Abu Simbel(ABS)Egyptian geomagnetic observatories were processed and found to be of good quality.In this study,Egyptian observatory data were tested during both quiet and disturbed events and compared with data from INTERMAGNET observatories worldwide at different latitudes and within a narrow range of longitudes in both hemispheres.This study investigated the relationships between magnetic field components from Egyptian observatories and those from INTERMAGNET observatories using graphical representations of the X components;Pearson’s correlation for the X,Y,Z,and F components;cross-correlation for the X component;and wavelet coherence for the F component.The results of this study showed a high correlation between Egyptian observatories and all utilized INTERMAGNET stations,except those located at high latitudes,during both quiet and disturbed events.Additionally,the study confirmed the observed consistency between Egyptian observatories and selected INTERMAGNET stations.Therefore,Egyptian observatories can feasibly fill the gap in the Middle East and North Africa.展开更多
The Low Earth Orbit(LEO)geomagnetic satellites provide a large number of high-precision measurements,which are crucial for researching the Secular Variation(SV)of the geomagnetic field.We employ the combined constella...The Low Earth Orbit(LEO)geomagnetic satellites provide a large number of high-precision measurements,which are crucial for researching the Secular Variation(SV)of the geomagnetic field.We employ the combined constellation data from the Chinese Seismo-Electromagnet Satellite(CSES)and Swarm satellites to extract the SV in China and surrounding areas,based on the Geomagnetic Virtual Observatory(GVO)method.On this basis,we have developed two GVO products:the core field,and the SV series.The accuracies of these products are assessed using ground observatories measurements and geomagnetic field model.Moreover,the results indicate that the GVO products align well with the series from ground observatories and the CHAOS model.The majority of root-mean-square deviation(RMSE)values of the core field series are less than 5 nT,consistent with the INTERMAGNET standards for quasi-definitive data.In the GVO core field series,the maximum accuracy of one-month and four-month intervals are 2.24 nT and 1.16 nT,respectively.In the GVO SV series,the maximum accuracy of one-month and four-month intervals are 2.03 nT/yr and 1.36 nT/yr,respectively.The GVO SV series effectively capture geomagnetic jerks without losing temporal resolution comparing with the recording of ground observatories.We demonstrate that the GVO method serves as an effective and precise tool for extracting SV information of geomagnetic fields.In the GVO products,the RMSE of the horizontal component exceeds that of the vertical component,and the magnitude of RMSE deviation correlates with solar activity levels.With more and more geomagnetic satellites in orbit,we wish to use multi-constellation magnetic satellite data to assess the geomagnetic field more accurately.展开更多
A geomagnetic observatory was established at Karachi （geog coord： 24.95°N, 167.14° E）, Pakistan in 1983 which comprised of AMOS-Ⅲ （Automatic Magnetic Observatory System）. In 2006 SUPARCO （Space and Up...A geomagnetic observatory was established at Karachi （geog coord： 24.95°N, 167.14° E）, Pakistan in 1983 which comprised of AMOS-Ⅲ （Automatic Magnetic Observatory System）. In 2006 SUPARCO （Space and Upper Atmosphere Research Commission） planned to upgrade the old observatory of Karachi in order to qualify it as an IMO （Intermagnet Magnetic Observatory）. Dr. Jean Rasson agreed to give support and assist us in the upgradation. BGS （British Geological Survey） provided a complete observatory instrument setup. Due to perturbations traceable to the increased urbanization, the observatory has been shifted to a site ＂Sonmiani＂, 80 km north-west of Karachi, where long term protection from cultural noise is offered. This site in a sparsely built research complex was selected after a magnetic survey. A new observatory has also been established at Islamabad （geog cord： 33.75° N, 72.87° E） which is mountainous region. SUPARCO purchased new equipment for the establishment of new observatories. Plan of upgradation of observatory at Quetta is also under consideration in order to improve the monitoring of geomagnetic field on the western part of Pakistan. Repeat station work has been done for the northern part of Pakistan with the collaboration of IRM, Belgium. The obtained results also compared with the global geomagnetic model （IGRF）.展开更多
Institutions of astronomic research within theChinese Academy of Sciences (CAS) are among thefirst to gain the access to the pilot project of the na-tional knowledge innovation program (KIP) carriedout at CAS. The ope...Institutions of astronomic research within theChinese Academy of Sciences (CAS) are among thefirst to gain the access to the pilot project of the na-tional knowledge innovation program (KIP) carriedout at CAS. The operating mechanism reform at Na-tional Astronomic Observatories (NAO) includes theestablishment of research teams and the introductionof a new system in which R&D projects are in展开更多
With the continuous exploration and research of low-carbon buildings in China,combined with foreign theories and practices,there are a few basic theoretical and practical projects for low-carbon construction in major ...With the continuous exploration and research of low-carbon buildings in China,combined with foreign theories and practices,there are a few basic theoretical and practical projects for low-carbon construction in major cities of China.However,throughout the entire academic research,there is still no comprehensive and clear guidance for the green and low-carbon research and transformation of rural self-built houses.Therefore,the existing development of low-carbon technology for rural self-built houses has been summarized,and some prospects for the future development of rural self-built houses have been summarized.It is hoped that this will have positive help for future rural low-carbon transformation.展开更多
Orbit insertion uncertainties can significantly affect the configuration stability of heliocentric gravitational wave(GW)observatories,necessitating valid configuration uncertainty propagation techniques.Current confi...Orbit insertion uncertainties can significantly affect the configuration stability of heliocentric gravitational wave(GW)observatories,necessitating valid configuration uncertainty propagation techniques.Current configuration uncertainty propagation methods suffer from drawbacks related to their high computational complexity.To this end,this study proposes a novel configuration uncertainty propagation method for heliocentric GW observatories to reduce the computational complexity.First,the angular momentum and phase angle were found to be the two core variables for the orbit propagation of heliocentric GW observatories,the analytical solutions of which were derived using a perturbation-averaging technique.Subsequently,a first-order sensitivity matrix of the configuration stability index with respect to the initial states was derived based on the analytical solutions of the angular momentum and phase angle.Semi-analytically sensitive directions were obtained based on the derived sensitivity matrix,which was further employed to reduce the terms of configuration uncertainty propagation.The performance of the proposed method was validated using the example of a Laser Interferometer Space Antenna(LISA)project by comparing it with several competitive methods.The numerical results show that the proposed reduced-order method has a relative error close to that of the conventional full-state method and reduces the computational complexity by more than 46.展开更多
[目的/意义]本研究立足国际视野,梳理和总结全球代表性体育智库的治理经验,通过本土化借鉴,为破解我国体育智库的发展瓶颈,提升我国体育智库治理水平和发展质量,建成具有国际影响力的中国特色新型体育智库提供理论支撑与实践启示。[方法...[目的/意义]本研究立足国际视野,梳理和总结全球代表性体育智库的治理经验,通过本土化借鉴,为破解我国体育智库的发展瓶颈,提升我国体育智库治理水平和发展质量,建成具有国际影响力的中国特色新型体育智库提供理论支撑与实践启示。[方法/过程]本研究主要采用文献资料法和个案研究法,对国外体育智库瑞士国际体育研究中心(International Centre for Sports Studies,CIES)的治理经验进行分析,并结合中国体育智库的发展情况得出现实启示。[结果/结论]作为国外代表性较强的体育智库,CIES具有清晰的组织使命与功能定位、扁平的内部架构与组织部门、协同的外部利益相关者视野;拥有学科多元的人才队伍、成熟稳定的财务系统、即时权威的信息数据;注重成果转化与文化传播的共享性、长期性、追踪性、娱乐性等;建构响应组织使命、重视社会资源、面向不同需求的人才培养课程。立足国情,借鉴国外优秀体育智库的治理经验,我国体育智库亟须健全治理体系,探索中国特色体育智库运行机制;优化资源供给,保障体育智库健康可持续发展;活化研究成果,提升体育智库国际影响力;联动高校平台,支持体育高端人才的培育。展开更多
文摘Geomagnetic observatory data are crucial for all branches of geophysics because they can contribute to earthquake research by detecting anomalies in the Earth’s magnetic field.Recently,data records from the Misallat(MLT)and Abu Simbel(ABS)Egyptian geomagnetic observatories were processed and found to be of good quality.In this study,Egyptian observatory data were tested during both quiet and disturbed events and compared with data from INTERMAGNET observatories worldwide at different latitudes and within a narrow range of longitudes in both hemispheres.This study investigated the relationships between magnetic field components from Egyptian observatories and those from INTERMAGNET observatories using graphical representations of the X components;Pearson’s correlation for the X,Y,Z,and F components;cross-correlation for the X component;and wavelet coherence for the F component.The results of this study showed a high correlation between Egyptian observatories and all utilized INTERMAGNET stations,except those located at high latitudes,during both quiet and disturbed events.Additionally,the study confirmed the observed consistency between Egyptian observatories and selected INTERMAGNET stations.Therefore,Egyptian observatories can feasibly fill the gap in the Middle East and North Africa.
基金supported by the Special Fund of the Institute of Geophysics,China Earthquake Administration(grant no.DQJB24X25).
文摘The Low Earth Orbit(LEO)geomagnetic satellites provide a large number of high-precision measurements,which are crucial for researching the Secular Variation(SV)of the geomagnetic field.We employ the combined constellation data from the Chinese Seismo-Electromagnet Satellite(CSES)and Swarm satellites to extract the SV in China and surrounding areas,based on the Geomagnetic Virtual Observatory(GVO)method.On this basis,we have developed two GVO products:the core field,and the SV series.The accuracies of these products are assessed using ground observatories measurements and geomagnetic field model.Moreover,the results indicate that the GVO products align well with the series from ground observatories and the CHAOS model.The majority of root-mean-square deviation(RMSE)values of the core field series are less than 5 nT,consistent with the INTERMAGNET standards for quasi-definitive data.In the GVO core field series,the maximum accuracy of one-month and four-month intervals are 2.24 nT and 1.16 nT,respectively.In the GVO SV series,the maximum accuracy of one-month and four-month intervals are 2.03 nT/yr and 1.36 nT/yr,respectively.The GVO SV series effectively capture geomagnetic jerks without losing temporal resolution comparing with the recording of ground observatories.We demonstrate that the GVO method serves as an effective and precise tool for extracting SV information of geomagnetic fields.In the GVO products,the RMSE of the horizontal component exceeds that of the vertical component,and the magnitude of RMSE deviation correlates with solar activity levels.With more and more geomagnetic satellites in orbit,we wish to use multi-constellation magnetic satellite data to assess the geomagnetic field more accurately.
文摘A geomagnetic observatory was established at Karachi （geog coord： 24.95°N, 167.14° E）, Pakistan in 1983 which comprised of AMOS-Ⅲ （Automatic Magnetic Observatory System）. In 2006 SUPARCO （Space and Upper Atmosphere Research Commission） planned to upgrade the old observatory of Karachi in order to qualify it as an IMO （Intermagnet Magnetic Observatory）. Dr. Jean Rasson agreed to give support and assist us in the upgradation. BGS （British Geological Survey） provided a complete observatory instrument setup. Due to perturbations traceable to the increased urbanization, the observatory has been shifted to a site ＂Sonmiani＂, 80 km north-west of Karachi, where long term protection from cultural noise is offered. This site in a sparsely built research complex was selected after a magnetic survey. A new observatory has also been established at Islamabad （geog cord： 33.75° N, 72.87° E） which is mountainous region. SUPARCO purchased new equipment for the establishment of new observatories. Plan of upgradation of observatory at Quetta is also under consideration in order to improve the monitoring of geomagnetic field on the western part of Pakistan. Repeat station work has been done for the northern part of Pakistan with the collaboration of IRM, Belgium. The obtained results also compared with the global geomagnetic model （IGRF）.
文摘Institutions of astronomic research within theChinese Academy of Sciences (CAS) are among thefirst to gain the access to the pilot project of the na-tional knowledge innovation program (KIP) carriedout at CAS. The operating mechanism reform at Na-tional Astronomic Observatories (NAO) includes theestablishment of research teams and the introductionof a new system in which R&D projects are in
文摘With the continuous exploration and research of low-carbon buildings in China,combined with foreign theories and practices,there are a few basic theoretical and practical projects for low-carbon construction in major cities of China.However,throughout the entire academic research,there is still no comprehensive and clear guidance for the green and low-carbon research and transformation of rural self-built houses.Therefore,the existing development of low-carbon technology for rural self-built houses has been summarized,and some prospects for the future development of rural self-built houses have been summarized.It is hoped that this will have positive help for future rural low-carbon transformation.
基金supported by the National Key R&D Program of China(2020YFC2201200).
文摘Orbit insertion uncertainties can significantly affect the configuration stability of heliocentric gravitational wave(GW)observatories,necessitating valid configuration uncertainty propagation techniques.Current configuration uncertainty propagation methods suffer from drawbacks related to their high computational complexity.To this end,this study proposes a novel configuration uncertainty propagation method for heliocentric GW observatories to reduce the computational complexity.First,the angular momentum and phase angle were found to be the two core variables for the orbit propagation of heliocentric GW observatories,the analytical solutions of which were derived using a perturbation-averaging technique.Subsequently,a first-order sensitivity matrix of the configuration stability index with respect to the initial states was derived based on the analytical solutions of the angular momentum and phase angle.Semi-analytically sensitive directions were obtained based on the derived sensitivity matrix,which was further employed to reduce the terms of configuration uncertainty propagation.The performance of the proposed method was validated using the example of a Laser Interferometer Space Antenna(LISA)project by comparing it with several competitive methods.The numerical results show that the proposed reduced-order method has a relative error close to that of the conventional full-state method and reduces the computational complexity by more than 46.
文摘[目的/意义]本研究立足国际视野,梳理和总结全球代表性体育智库的治理经验,通过本土化借鉴,为破解我国体育智库的发展瓶颈,提升我国体育智库治理水平和发展质量,建成具有国际影响力的中国特色新型体育智库提供理论支撑与实践启示。[方法/过程]本研究主要采用文献资料法和个案研究法,对国外体育智库瑞士国际体育研究中心(International Centre for Sports Studies,CIES)的治理经验进行分析,并结合中国体育智库的发展情况得出现实启示。[结果/结论]作为国外代表性较强的体育智库,CIES具有清晰的组织使命与功能定位、扁平的内部架构与组织部门、协同的外部利益相关者视野;拥有学科多元的人才队伍、成熟稳定的财务系统、即时权威的信息数据;注重成果转化与文化传播的共享性、长期性、追踪性、娱乐性等;建构响应组织使命、重视社会资源、面向不同需求的人才培养课程。立足国情,借鉴国外优秀体育智库的治理经验,我国体育智库亟须健全治理体系,探索中国特色体育智库运行机制;优化资源供给,保障体育智库健康可持续发展;活化研究成果,提升体育智库国际影响力;联动高校平台,支持体育高端人才的培育。
