The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geo...The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.展开更多
Background The Global Cancer Observatory(GLOBOCAN)2022 and the Global Burden of Disease(GBD)2021 are two primary databases for assessing the global cancer burden.This study aimed to compare the incidence and mortality...Background The Global Cancer Observatory(GLOBOCAN)2022 and the Global Burden of Disease(GBD)2021 are two primary databases for assessing the global cancer burden.This study aimed to compare the incidence and mortality rates of tracheal,bronchus,and lung(TBL)cancer reported in these databases and to analyze the observed discrepancies.Methods Age-standardized rates(ASRs),including age-standardized incidence rates and age-standardized mortality rates for TBL cancer,were obtained from GLOBOCAN 2022 and GBD 2021 for the most recent available year.Differences in ASRs at the national level between the two databases were quantified using pairwise differences,calculated as the absolute difference in ASRs divided by the mean of the ASRs from both sources.Correlations between macroeconomic factors and pairwise differences in ASRs were evaluated,and country features correlated with high pairwise differences were assessed.The data sources and methods used in the two databases were also compared.Results Strong correlations were identified between ASRs reported by GLOBOCAN 2022 and GBD 2021;however,significant differences were observed between estimates from the two data sources.African countries commonly exhibited larger pairwise differences in ASRs,whereas European countries demonstrated smaller pairwise differences in ASRs.Additionally,some populous developing countries,including China,South Africa,Brazil and India,showed smaller differences in ASRs.Countries lacking vital registration systems or high-quality population-based cancer registries displayed larger differences in ASRs.Furthermore,differences in ASRs were negatively correlated with macroeconomic factors.The data sources and estimation methods used by the two databases were inconsistent.Conclusions Discrepancies in TBL cancer incidence and mortality were observed between GLOBOCAN 2022 and GBD 2021.While differences in sources and methods partially explain these discrepancies,a country's cancer surveillance maturity and economic status also correlate with the accuracy of the estimates.Estimating the cancer burden in less wealthy countries remains a substantial challenge,necessitating long-term assistance and investment.展开更多
This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stabl...This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stable configuration is essential for the continuous observation of gravitational waves(GWs).However,the motion near the collinear libration points is highly unstable.This problem is examined by output regulation theory.Using the tracking aspect,the equilateral triangular array formation is established in two periods and the fuel consumption is calculated.Furthermore,the natural evolution of the formation without control input is analyzed,and the effective stability duration is quantified to determine the timing of control interventions.Finally,to observe the GWs in same direction with different frequency bands,scale reconfiguration is employed.展开更多
Configuration stability is essential for a space-based Gravitational-Wave(GW)observatory,which can be impacted by orbit insertion uncertainties.Configuration uncertainty propagation is vital for investigating the infl...Configuration stability is essential for a space-based Gravitational-Wave(GW)observatory,which can be impacted by orbit insertion uncertainties.Configuration uncertainty propagation is vital for investigating the influences of uncertainties on configuration stability and can be potentially useful in the navigation and control of GW observatories.Current methods suffer from drawbacks related to high computational burden.To this end,a Radial-Tangential-Ddirectional State Transition Tensor(RT-DSTT)-based configuration uncertainty propagation method is proposed.First,two sensitive directions are found by capturing the dominant secular terms.Considering the orbit insertion errors along the two sensitive directions only,a reduced-order RT-DSTT model is developed for orbital uncertainty propagation.Then,the relationship between the uncertainties in the orbital states and the uncertainties in the configuration stability indexes is mapped using highorder derivatives.The result is a semi-analytical solution that can predict the deviations in the configuration stability indexes given orbit insertion errors.The potential application of the proposed RT-DSTT-based method in calculating the feasible domain is presented.The performance of the proposed method is validated on the Laser Interferometer Space Antenna(LISA)project.Simulations show that the proposed method can provide similar results to the STT-based method but requires only half of the computational time.展开更多
Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of t...Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of the celestial bodies, the same celestial object will have different positions in different catalogs, making it difficult to integrate multi-band or full-band astronomical data. In this study, we propose an online cross-matching method based on pseudo-spherical indexing techniques and develop a service combining with high performance computing system(Taurus) to improve cross-matching efficiency, which is designed for the Data Center of Xinjiang Astronomical Observatory. Specifically, we use Quad Tree Cube to divide the spherical blocks of the celestial object and map the 2D space composed of R.A. and decl. to 1D space and achieve correspondence between real celestial objects and spherical patches. Finally, we verify the performance of the service using Gaia 3 and PPMXL catalogs. Meanwhile, we send the matching results to VO tools-Topcat and Aladin respectively to get visual results. The experimental results show that the service effectively solves the speed bottleneck problem of crossmatching caused by frequent I/O, and significantly improves the retrieval and matching speed of massive astronomical data.展开更多
Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and distorted.Severe distortion in speckle images impedes image phase deviat...Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and distorted.Severe distortion in speckle images impedes image phase deviation in the speckle masking reconstruction method,leading to the appearance of spurious imaging artifacts.Relying only on linear image degradation principles to reconstruct solar images is insufficient.To solve this problem,we propose the multiframe blind deconvolution combined with non-rigid alignment(MFBD-CNRA)method for solar image reconstruction.We consider image distortion caused by atmospheric turbulence and use non-rigid alignment to correct pixel-level distortion,thereby achieving nonlinear constraints to complement image intensity changes.After creating the corrected speckle image,we use the linear method to solve the wavefront phase,obtaining the target image.We verify the effectiveness of our method results,compared with others,using solar observation data from the 1 m new vacuum solar telescope(NVST).This new method successfully reconstructs high-resolution images of solar observations with a Fried parameter r0 of approximately 10 cm,and enhances images at high frequency.When r0 is approximately 5 cm,the new method is even more effective.It reconstructs the edges of solar graining and sunspots,and is greatly enhanced at mid and high frequency compared with other methods.Comparisons confirm the effectiveness of this method,with respect to both nonlinear and linear constraints in solar image reconstruction.This provides a suitable solution for image reconstruction in ground-based solar observations under strong atmospheric turbulence.展开更多
A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/s...A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/sec Ethemet communication, can be transmitted from the shore to the seafloor through an umbilical armored cable. A subsea junction box is fixed at a cable terminal, enabling the extension of up to nine connections. The box consists of three main pressure vessels that perform power conversion, power distribution, and real-time communication functions. A method of stacking modules is used to design the power conversion system in order to reduce the 10 kV voltage to levels that can power the attached instruments. A power distribution system and an Ethemet communication system are introduced to control the power supply and transmit data or commands between the terminals and the shore station, respectively. Specific validations of all sections were qualified in a laboratory environment prior to the sea trial. The ocean observatory system was then deployed at the coast of the East China Sea along with three in situ instruments for a 14-day test. The results show that this high voltage-powered observatory system is effective for subsea long-term and real-time observations.展开更多
We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telesco...We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telescope(Mephisto).The Mephisto is under construction.The ASMS has been running on robotic mode since 2017.The core instruments:Cloud Sensor,All-Sky Camera and AutonomousDIMM that are developed by our group,together with the commercial Meteorological Station and Sky Quality Meter,are combined into the astronomical optical site monitoring system.The new Cloud Sensor's Cloud-Clear Relationship is presented for the first time,which is used to calculate the All-Sky cloud cover.We designed the Autonomous-DIMM located on a tower,with the same height as LJT.The seeing data have been observed for a full year.ASMS's data for the year 2019 are also analysed in detail,which are valuable to observers.展开更多
Beryllium-7 （^7Be） and lead-210 （^210pb） activities were measured from October 2002 to January 2004 at Waliguan Observatory （WO： 36.287°N, 100.898°E, 3816 m a.s.l （above sea level） in northwest China...Beryllium-7 （^7Be） and lead-210 （^210pb） activities were measured from October 2002 to January 2004 at Waliguan Observatory （WO： 36.287°N, 100.898°E, 3816 m a.s.l （above sea level） in northwest China. ^7Be and ^210pb activities are high with overall averages of 14.74-3.5 mBq m^-3 and 1.8±0.8 mBq m^-3 respectively. For both 7Be and ^210pb, there are significant short-term and seasonal variations with a commonly low value in summer （May-September） and a monthly maximum in April （for ^7Be） and in December （for ^210pb）. The ratio of ^7Be/^210pb showed a broad maximum extending from April to July, coinciding with a seasonal peak in surface ozone （O3）. The seasonal cycles of ^7Be and ^210pb activities were greatly influenced by precipitation and thermal dynamical conditions over the boundary layer, especially for ^210Pb. The vertical mixing process between the boundary layer and the aloft air modulates the variations of ^7Be and ^210pb at WO in summer. It is indicated that air mass had longer residence time and originated from higher altitudes at WO in the spring-summer time and the winter in 2003. During an event with extremely high weeklyaveraged ^7Be concentration （24.8 mBq m^-3） together with high O3 levels and low water mixing ratio, we found that air masses had been convectively transported a long distance to WO from high latitude source regions in central Asia, where significant subsiding motions were observed. In another case with the extreme ^210pb activity of 5.7 mBq m^-3 high CO2 level and specific humidity （in winter）, air masses had come from south China and north Indian regions where 222Rn activities were high. This study, using ^7Be and ^210pb as atmospheric tracers, has revealed that complex interactions of convective mixing from the upper troposphere and long-range transports exist at WO.展开更多
Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the...Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the observatory building and laser-strain meters in the gallery. The question arises how non-tidal signals are displayed in the measured time series. The investigation of such signals which can be caused naturally or man-made, can result in different sensitivities for the various tilt- and strainmeter systems, e.g. regarding barometric pressure impacts and hydrological induced pore pressure effects.展开更多
Due to the metropolitan area of immense diversity and breadth of their construction activities, the performance of activities at districts level, cannot be precisely evaluated. Therefore, generally, it monitors only t...Due to the metropolitan area of immense diversity and breadth of their construction activities, the performance of activities at districts level, cannot be precisely evaluated. Therefore, generally, it monitors only the indices which are defined for those functions. Furthermore, district-based development policy, and decentralization of governance, necessitate more local autonomy, which requires closer monitors of districts for being sure of its movements in the frame of urban developing plans. The advancement of technology has created the expectation that we can monitor all details of the metropolitan administrative processes and involve them in decision support systems for urban management. In this study, a web based SDSS prototype has been implemented to monitor the Tehran development plans progress at districts level. This interactive system presents a map of Tehran which indicates the realization of each component of the city master plan in different parts of town. The design of system lets all districts produce and support their own reporting maps, and it presents them in their dedicated place of city map by snapping all districts reports, when a city report arises. Also it elaborates the problem of implementing and proposes “cloud computing facilities” as a solution.展开更多
This paper describes the system modelling, architecture design and implementation of the observatory control system （OCS） of the LAMOST （Large Area Multi-Object Fibre Spectroscopic Telescope）. The software-reuse t...This paper describes the system modelling, architecture design and implementation of the observatory control system （OCS） of the LAMOST （Large Area Multi-Object Fibre Spectroscopic Telescope）. The software-reuse technique, object-oriented technique, component and framework based software-developing methodology are used in the system architecture and implementation. The architecture of OCS is established based on a component-based layered system using many patterns such as the MVC （Model/View/Controller） and proxy. For the effective and safe exchange of commands and status between OCS and the subsystem, a unified message bus is defined and three protocols, namely a command acceptance/rejection protocol, a command execution feedback protocol and a status handling protocol, are proposed. The interface protocol between all the subsystems is defined. The full utilization of advanced computer technologies including the database, distributed computing, real-time computing, standard data exchange and expert system technologies has benefited the OCS software development.展开更多
An advanced ocean observatory has been established in Lunenburg Bay of Nova Scotia, Canada as part of an interdisciplinary research project of marine environmental prediction. The development of a high-resolution coas...An advanced ocean observatory has been established in Lunenburg Bay of Nova Scotia, Canada as part of an interdisciplinary research project of marine environmental prediction. The development of a high-resolution coastal circulation model is one of important components of the observatory. The model horizontal resolution is 60 m and the vertical resolution is about 1 m. The coastal circulation model is used to simulate the semi-diurnal tidal circulation and associated nonlinear dynamics with the M2 forcing specified at the model open boundaries. The model is also used to simulate the storm-induced circulation in the bay during Hurricane Juan in September 2003, with the model forcing to be the combination of tides and remotely generated waves specified at the model open boundaries and wind stress applied at the sea surface. The model results demonstrate strong interactions between the local wind stress, tidal forcing, and remotely generated waves during this period. Comparison of model results with the surface elevation and current observations demonstrates that the coastal circulation model has reasonable skills in simulating the tidal and storm-induced circulation in the bay.展开更多
One of the greatest challenges in critical zone studies is to document the moisture dynamics, water flux,and solute chemistry of the unsaturated, fractured and weathered bedrock that lies between the soil and groundwa...One of the greatest challenges in critical zone studies is to document the moisture dynamics, water flux,and solute chemistry of the unsaturated, fractured and weathered bedrock that lies between the soil and groundwater table. The central impediment to quantifying this component of the subsurface is the difficulty associated with direct observations. Here, we report solute chemistry as a function of depth collected over a full year across the shale-derived vadose zone of the Eel River Critical Zone Observatory using a set of novel sub-horizontal wellbores,referred to as the vadose zone monitoring system. The results of this first geochemical glimpse into the deep vadose zone indicate a dynamic temporal and depth-resolved structure. Major cation concentrations reflect seasonal changes in precipitation and water saturation, and normalized ratios span the full range of values reported for the world's largest rivers.展开更多
This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detaile...This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detailed querying a virtual observatory s resources. The overview is focused on enhancements of user experience, work with simple application messaging protocol(SAMP) and other interoperability that improves work with global list of spectra, plot window and analysis menu.展开更多
The Xinjiang Astronomical Observatory Data Center faces issues related to delay-affected services. As a result, these services cannot be implemented in a timely manner due to the overloading of transmission links. In ...The Xinjiang Astronomical Observatory Data Center faces issues related to delay-affected services. As a result, these services cannot be implemented in a timely manner due to the overloading of transmission links. In this paper, the software-defined network technology is applied to the Xinjiang Astronomical Observatory Data Center Network(XAODCN). Specifically, a novel reconfiguration method is proposed to realise the software-defined Xinjiang Astronomical Observatory Data Center Network(SDXAO-DCN), and a network model is constructed. To overcome the congestion problem, a traffic load-balancing algorithm is designed for fast transmission of the service traffic by combining three factors: network structure, congestion level and transmission service. The proposed algorithm is compared with current commonly load-balancing algorithms which are used in data center to verify its efficiency. Simulation experiments show that the algorithm improved transmission performance and transmission quality for the SDXAO-DCN.展开更多
Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform...Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform the processing and analysis of geomagnetic parameters through different spectral,statistical and correlation methods.All these parameters are included in the geomagnetic database on server.The web interface for the database meets the different needs of handling the data collected,raw or processed.The server-side programming language used for design is php.This allow us to select different periods for which access to stored data,required for different search filters and different parameters or data from different time periods can be compared.For a more in-depth analysis of the stored data,through JavaScript programming language graphs for different parameters can be drawn.Access to the web interface can be done with or without authentication,depending on the need to ensure the security of certain data collected,stored and processed.The applications are scalable for different devices that will access it:mobile,tablets,laptops or desktops.展开更多
The NCU (National Central University) Lu Lin Observatory (Fig. 1) is located at Mt. Front Lu Lin, 120°52′25″E and 23°28′07″N, a 2862 m peak in the Yu Shan National Park. The construction of Lu Lin Observ...The NCU (National Central University) Lu Lin Observatory (Fig. 1) is located at Mt. Front Lu Lin, 120°52′25″E and 23°28′07″N, a 2862 m peak in the Yu Shan National Park. The construction of Lu Lin Observatory was finished on January 14, 1999. The initial study of Lu Lin site was started since late 1989. Later on, a three year project was founded by the National Science Council (NSC) which supported the development of a modern seeing monitor for this site survey study from 1990 through 1993. The average seeing of Lu Lin site is about 1.39 arc second with average 200 clear nights annually. The sky background of this site is 20.72 mag/arcsec 2 in V band and 21.22 mag/arcsec 2 in B band. The Lu Lin observatory is developed for both research and education activity. A homemade 76 cm Super Light Telescope (SLT) and three TAOS’s 50 cm robotic telescopes will be the two major research facilities. The SLT is expected to be operated in the fall of 1999. We are proposing a pilot program to perform SLT observations of time varying astrophysical objects exploiting the unique geophysical location (e. g. time and longitudinal coverage) of Taiwan at the Western Pacific Rim in such topics of emerging interest. The TAOS’s telescopes will be installed in the late 1999 for the survey work of Kuiper Belt Objects. A wireless T1 Network system will also be build up for future remote observation.展开更多
A 61 element adaptive optical system has been preliminary tested in the Coudé path of the 1 2m telescope at the Yunnan observatory this year. The whole system will be fully operated next year. This paper describe...A 61 element adaptive optical system has been preliminary tested in the Coudé path of the 1 2m telescope at the Yunnan observatory this year. The whole system will be fully operated next year. This paper describes the AO system performances and its first experiment results, and the possible astronomical research topics.展开更多
We carried out spectroscopic observations of several supernovae with 1 01m telescope at Bisei Astronomical Observatory, in order to investigate the type and characteristics soon after the discovery. Most of the observ...We carried out spectroscopic observations of several supernovae with 1 01m telescope at Bisei Astronomical Observatory, in order to investigate the type and characteristics soon after the discovery. Most of the observed supernovae were of type Ia. We present here some examples of the spectra and describe the necessity of the follow up observation site in East Asia.展开更多
基金the National Research and InnovationAgency of Indonesia (BRIN) under research grant Rumah Program Kebencanaan 2022-2025support from the Earth Observatory Singapore (EOS)supported by the Ministry of Higher Education, Science,and Technology, and Institut Teknologi Bandung through the Indonesian Collaborative Research Program.
文摘The Lembang Fault is a major geological feature in West Java that borders the northern edge of Bandung(one of Indonesia’s largest cities).It lies just south of the active Tangkuban Perahu Volcano,exhibiting clear geomorphic signs of recent activity,and has been scientifically confirmed as active through geological and geophysical studies.In this work,we describe an Integrated along the Lembang Fault,which can be used for geodynamic research in Indonesia.We discuss the design of a seismic and Global Navigation Satellite System(GNSS)array sensor network for continuous monitoring,and report the status of monitoring stations that periodically collect highly accurate,continuous seismographic and GNSS readings,transmitting these data to a central server in Bandung for post-processing.Solutions from the array data are used to provide precise measurements of the deformation of the Earth’s surface over large distances,allowing for spatio-temporal tracking of tectonic movement,and resulting in a better understanding of seismic events in the region.In this study,our investigation revealed a significant compression rate of an estimated 13 microstrain/yr along the Lembang Fault,whereas the strain rate is much smaller farther south of the fault.This study presents the design of a seismo-geodetic observatory network that can be implemented in earthquake-prone regions for mitigation purposes,with particular utility for studying other active faults that also traverse populated areas in Indonesia.
基金supported by the Major Program of Scientific and Technical Innovation 2030(grant number:2020AAA0109504)the Science and Technology Planning Project of Beijing City(grant number:Z191100006619116).
文摘Background The Global Cancer Observatory(GLOBOCAN)2022 and the Global Burden of Disease(GBD)2021 are two primary databases for assessing the global cancer burden.This study aimed to compare the incidence and mortality rates of tracheal,bronchus,and lung(TBL)cancer reported in these databases and to analyze the observed discrepancies.Methods Age-standardized rates(ASRs),including age-standardized incidence rates and age-standardized mortality rates for TBL cancer,were obtained from GLOBOCAN 2022 and GBD 2021 for the most recent available year.Differences in ASRs at the national level between the two databases were quantified using pairwise differences,calculated as the absolute difference in ASRs divided by the mean of the ASRs from both sources.Correlations between macroeconomic factors and pairwise differences in ASRs were evaluated,and country features correlated with high pairwise differences were assessed.The data sources and methods used in the two databases were also compared.Results Strong correlations were identified between ASRs reported by GLOBOCAN 2022 and GBD 2021;however,significant differences were observed between estimates from the two data sources.African countries commonly exhibited larger pairwise differences in ASRs,whereas European countries demonstrated smaller pairwise differences in ASRs.Additionally,some populous developing countries,including China,South Africa,Brazil and India,showed smaller differences in ASRs.Countries lacking vital registration systems or high-quality population-based cancer registries displayed larger differences in ASRs.Furthermore,differences in ASRs were negatively correlated with macroeconomic factors.The data sources and estimation methods used by the two databases were inconsistent.Conclusions Discrepancies in TBL cancer incidence and mortality were observed between GLOBOCAN 2022 and GBD 2021.While differences in sources and methods partially explain these discrepancies,a country's cancer surveillance maturity and economic status also correlate with the accuracy of the estimates.Estimating the cancer burden in less wealthy countries remains a substantial challenge,necessitating long-term assistance and investment.
基金supported by the China Scholarship Council(CSC)(No.202206290131)。
文摘This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stable configuration is essential for the continuous observation of gravitational waves(GWs).However,the motion near the collinear libration points is highly unstable.This problem is examined by output regulation theory.Using the tracking aspect,the equilateral triangular array formation is established in two periods and the fuel consumption is calculated.Furthermore,the natural evolution of the formation without control input is analyzed,and the effective stability duration is quantified to determine the timing of control interventions.Finally,to observe the GWs in same direction with different frequency bands,scale reconfiguration is employed.
基金supported by the National Key R&D Program of China(No.2020YFC2201200).
文摘Configuration stability is essential for a space-based Gravitational-Wave(GW)observatory,which can be impacted by orbit insertion uncertainties.Configuration uncertainty propagation is vital for investigating the influences of uncertainties on configuration stability and can be potentially useful in the navigation and control of GW observatories.Current methods suffer from drawbacks related to high computational burden.To this end,a Radial-Tangential-Ddirectional State Transition Tensor(RT-DSTT)-based configuration uncertainty propagation method is proposed.First,two sensitive directions are found by capturing the dominant secular terms.Considering the orbit insertion errors along the two sensitive directions only,a reduced-order RT-DSTT model is developed for orbital uncertainty propagation.Then,the relationship between the uncertainties in the orbital states and the uncertainties in the configuration stability indexes is mapped using highorder derivatives.The result is a semi-analytical solution that can predict the deviations in the configuration stability indexes given orbit insertion errors.The potential application of the proposed RT-DSTT-based method in calculating the feasible domain is presented.The performance of the proposed method is validated on the Laser Interferometer Space Antenna(LISA)project.Simulations show that the proposed method can provide similar results to the STT-based method but requires only half of the computational time.
基金supported by the National Key R&D Program of China (Nos. 2022YFF0711502 and 2021YFC2203502)the National Natural Science Foundation of China (NSFC)(12173077 and 12003062)+6 种基金the Tianshan Innovation Team Plan of Xinjiang Uygur Autonomous Region (2022D14020)the Tianshan Talent Project of Xinjiang Uygur Autonomous Region(2022TSYCCX0095)the Scientific Instrument Developing Project of the Chinese Academy of Sciences (grant No. PTYQ2022YZZD01)China National Astronomical Data Center (NADC)the Operation,Maintenance and Upgrading Fund for Astronomical Telescopes and Facility Instruments,budgeted from the Ministry of Finance of China (MOF)and administrated by the Chinese Academy of Sciences (CAS)Natural Science Foundation of Xinjiang Uygur Autonomous Region (2022D01A360)supported by Astronomical Big Data Joint Research Center,co-founded by National Astronomical Observatories,Chinese Academy of Sciences。
文摘Cross-matching is a key technique to achieve fusion of multi-band astronomical catalogs. Due to different equipment such as various astronomical telescopes, the existence of measurement errors, and proper motions of the celestial bodies, the same celestial object will have different positions in different catalogs, making it difficult to integrate multi-band or full-band astronomical data. In this study, we propose an online cross-matching method based on pseudo-spherical indexing techniques and develop a service combining with high performance computing system(Taurus) to improve cross-matching efficiency, which is designed for the Data Center of Xinjiang Astronomical Observatory. Specifically, we use Quad Tree Cube to divide the spherical blocks of the celestial object and map the 2D space composed of R.A. and decl. to 1D space and achieve correspondence between real celestial objects and spherical patches. Finally, we verify the performance of the service using Gaia 3 and PPMXL catalogs. Meanwhile, we send the matching results to VO tools-Topcat and Aladin respectively to get visual results. The experimental results show that the service effectively solves the speed bottleneck problem of crossmatching caused by frequent I/O, and significantly improves the retrieval and matching speed of massive astronomical data.
基金sponsored by the National Natural Science Foundation of China(NSFC)under the grant numbers(11773073,11873027,U2031140,11833010)Yunnan Key Laboratory of Solar Physics and Space Science under the number 202205AG070009+1 种基金Yunnan Provincial Science and Technology Department(202103AD50013,202105AB160001,202305AH340002)the GHfund A202302013242 and CAS“Light of West China”Program 202305AS350029.
文摘Strong atmospheric turbulence reduces astronomical seeing,causing speckle images acquired by ground-based solar telescopes to become blurred and distorted.Severe distortion in speckle images impedes image phase deviation in the speckle masking reconstruction method,leading to the appearance of spurious imaging artifacts.Relying only on linear image degradation principles to reconstruct solar images is insufficient.To solve this problem,we propose the multiframe blind deconvolution combined with non-rigid alignment(MFBD-CNRA)method for solar image reconstruction.We consider image distortion caused by atmospheric turbulence and use non-rigid alignment to correct pixel-level distortion,thereby achieving nonlinear constraints to complement image intensity changes.After creating the corrected speckle image,we use the linear method to solve the wavefront phase,obtaining the target image.We verify the effectiveness of our method results,compared with others,using solar observation data from the 1 m new vacuum solar telescope(NVST).This new method successfully reconstructs high-resolution images of solar observations with a Fried parameter r0 of approximately 10 cm,and enhances images at high frequency.When r0 is approximately 5 cm,the new method is even more effective.It reconstructs the edges of solar graining and sunspots,and is greatly enhanced at mid and high frequency compared with other methods.Comparisons confirm the effectiveness of this method,with respect to both nonlinear and linear constraints in solar image reconstruction.This provides a suitable solution for image reconstruction in ground-based solar observations under strong atmospheric turbulence.
基金supported by the National High-Technology Research and Development Program of China(Grant No.2007AA091201-1)
文摘A cabled ocean observatory system that can provide abundant power and broad bandwidth communication for undersea instruments is developed. A 10 kV direct current （kVDC） with up to 10 kW power, along with l Gigabit/sec Ethemet communication, can be transmitted from the shore to the seafloor through an umbilical armored cable. A subsea junction box is fixed at a cable terminal, enabling the extension of up to nine connections. The box consists of three main pressure vessels that perform power conversion, power distribution, and real-time communication functions. A method of stacking modules is used to design the power conversion system in order to reduce the 10 kV voltage to levels that can power the attached instruments. A power distribution system and an Ethemet communication system are introduced to control the power supply and transmit data or commands between the terminals and the shore station, respectively. Specific validations of all sections were qualified in a laboratory environment prior to the sea trial. The ocean observatory system was then deployed at the coast of the East China Sea along with three in situ instruments for a 14-day test. The results show that this high voltage-powered observatory system is effective for subsea long-term and real-time observations.
基金the National Natural Science Foundation of China(NSFC,Grant Nos.11991051,11203073,11573067,11873092 and 11803087)the CAS“Light of West China”Program(No.Y8XB018001)。
文摘We installed two sets of Astronomical Site Monitoring Systems(ASMSs)at Lijiang Observatory(GMG),for the running of the 2.4-meter Lijiang optical telescope(LJT)and the 1.6-meter Multi-channel Photometric Survey Telescope(Mephisto).The Mephisto is under construction.The ASMS has been running on robotic mode since 2017.The core instruments:Cloud Sensor,All-Sky Camera and AutonomousDIMM that are developed by our group,together with the commercial Meteorological Station and Sky Quality Meter,are combined into the astronomical optical site monitoring system.The new Cloud Sensor's Cloud-Clear Relationship is presented for the first time,which is used to calculate the All-Sky cloud cover.We designed the Autonomous-DIMM located on a tower,with the same height as LJT.The seeing data have been observed for a full year.ASMS's data for the year 2019 are also analysed in detail,which are valuable to observers.
基金the National Science Foundation of China （Grant Nos. 40175032 , 40575013）.
文摘Beryllium-7 （^7Be） and lead-210 （^210pb） activities were measured from October 2002 to January 2004 at Waliguan Observatory （WO： 36.287°N, 100.898°E, 3816 m a.s.l （above sea level） in northwest China. ^7Be and ^210pb activities are high with overall averages of 14.74-3.5 mBq m^-3 and 1.8±0.8 mBq m^-3 respectively. For both 7Be and ^210pb, there are significant short-term and seasonal variations with a commonly low value in summer （May-September） and a monthly maximum in April （for ^7Be） and in December （for ^210pb）. The ratio of ^7Be/^210pb showed a broad maximum extending from April to July, coinciding with a seasonal peak in surface ozone （O3）. The seasonal cycles of ^7Be and ^210pb activities were greatly influenced by precipitation and thermal dynamical conditions over the boundary layer, especially for ^210Pb. The vertical mixing process between the boundary layer and the aloft air modulates the variations of ^7Be and ^210pb at WO in summer. It is indicated that air mass had longer residence time and originated from higher altitudes at WO in the spring-summer time and the winter in 2003. During an event with extremely high weeklyaveraged ^7Be concentration （24.8 mBq m^-3） together with high O3 levels and low water mixing ratio, we found that air masses had been convectively transported a long distance to WO from high latitude source regions in central Asia, where significant subsiding motions were observed. In another case with the extreme ^210pb activity of 5.7 mBq m^-3 high CO2 level and specific humidity （in winter）, air masses had come from south China and north Indian regions where 222Rn activities were high. This study, using ^7Be and ^210pb as atmospheric tracers, has revealed that complex interactions of convective mixing from the upper troposphere and long-range transports exist at WO.
文摘Since end of the 90s of the last century the seismological station Moxa was extended and developed into the modern Geodynamic Observatory. It comprises also the new installation of borehole-tilt meters in front of the observatory building and laser-strain meters in the gallery. The question arises how non-tidal signals are displayed in the measured time series. The investigation of such signals which can be caused naturally or man-made, can result in different sensitivities for the various tilt- and strainmeter systems, e.g. regarding barometric pressure impacts and hydrological induced pore pressure effects.
文摘Due to the metropolitan area of immense diversity and breadth of their construction activities, the performance of activities at districts level, cannot be precisely evaluated. Therefore, generally, it monitors only the indices which are defined for those functions. Furthermore, district-based development policy, and decentralization of governance, necessitate more local autonomy, which requires closer monitors of districts for being sure of its movements in the frame of urban developing plans. The advancement of technology has created the expectation that we can monitor all details of the metropolitan administrative processes and involve them in decision support systems for urban management. In this study, a web based SDSS prototype has been implemented to monitor the Tehran development plans progress at districts level. This interactive system presents a map of Tehran which indicates the realization of each component of the city master plan in different parts of town. The design of system lets all districts produce and support their own reporting maps, and it presents them in their dedicated place of city map by snapping all districts reports, when a city report arises. Also it elaborates the problem of implementing and proposes “cloud computing facilities” as a solution.
基金supported by National Large-Scale Scientific ProjectsCAS K.C.Wong Post-doctoral Fellowships from CAS K.C. Wong Education Foundation
文摘This paper describes the system modelling, architecture design and implementation of the observatory control system （OCS） of the LAMOST （Large Area Multi-Object Fibre Spectroscopic Telescope）. The software-reuse technique, object-oriented technique, component and framework based software-developing methodology are used in the system architecture and implementation. The architecture of OCS is established based on a component-based layered system using many patterns such as the MVC （Model/View/Controller） and proxy. For the effective and safe exchange of commands and status between OCS and the subsystem, a unified message bus is defined and three protocols, namely a command acceptance/rejection protocol, a command execution feedback protocol and a status handling protocol, are proposed. The interface protocol between all the subsystems is defined. The full utilization of advanced computer technologies including the database, distributed computing, real-time computing, standard data exchange and expert system technologies has benefited the OCS software development.
基金This project is part of the CMEP project supported by the Canadian Foundation for Climate and Atmospheric Studies(CFCAS)J.S.is also supported bv NSERC,MARTEC(a Halifax based company),and the Meteorological Service of Canada(MSC)through the NSERC/MARTEC/MSC Industrial Research Chair in‘Regional Ocean M odelling and Prediction’.
文摘An advanced ocean observatory has been established in Lunenburg Bay of Nova Scotia, Canada as part of an interdisciplinary research project of marine environmental prediction. The development of a high-resolution coastal circulation model is one of important components of the observatory. The model horizontal resolution is 60 m and the vertical resolution is about 1 m. The coastal circulation model is used to simulate the semi-diurnal tidal circulation and associated nonlinear dynamics with the M2 forcing specified at the model open boundaries. The model is also used to simulate the storm-induced circulation in the bay during Hurricane Juan in September 2003, with the model forcing to be the combination of tides and remotely generated waves specified at the model open boundaries and wind stress applied at the sea surface. The model results demonstrate strong interactions between the local wind stress, tidal forcing, and remotely generated waves during this period. Comparison of model results with the surface elevation and current observations demonstrates that the coastal circulation model has reasonable skills in simulating the tidal and storm-induced circulation in the bay.
基金supported by the US National Science Foundation,Project EAR-1331904 for the Eel River Critical Zone Observatory
文摘One of the greatest challenges in critical zone studies is to document the moisture dynamics, water flux,and solute chemistry of the unsaturated, fractured and weathered bedrock that lies between the soil and groundwater table. The central impediment to quantifying this component of the subsurface is the difficulty associated with direct observations. Here, we report solute chemistry as a function of depth collected over a full year across the shale-derived vadose zone of the Eel River Critical Zone Observatory using a set of novel sub-horizontal wellbores,referred to as the vadose zone monitoring system. The results of this first geochemical glimpse into the deep vadose zone indicate a dynamic temporal and depth-resolved structure. Major cation concentrations reflect seasonal changes in precipitation and water saturation, and normalized ratios span the full range of values reported for the world's largest rivers.
基金supported by Agency of the Czech Republic-GACR(No.P103/13/08195S)the Development of Human Resources in Research and Development of Latest Soft Computing Methods and Their Application in Practical Project,Operational Programm Education for Competitiveness(No.CZ.1.07/2.3.00/20.0072)+1 种基金ESF State Budget of the Czech Republic,SGS(No.SP2013/114)VBTechnical University of Ostrava,Czech Republic
文摘This paper presents overview of new features so far prepared for new version of spectral analysis tool SPLAT-VO that allows to retrieve a large amount of spectra(and other data) based on its characteristics by detailed querying a virtual observatory s resources. The overview is focused on enhancements of user experience, work with simple application messaging protocol(SAMP) and other interoperability that improves work with global list of spectra, plot window and analysis menu.
基金supported by National Key R&D Program of China No.2021YFC2203502the National Natural Science Foundation of China (NSFC)(11803080,12173077,11873082,12003062)+2 种基金the Tianshan Innovation Team Plan of Xinjiang Uygur Autonomous Region (2022D14020)the Youth Innovation Promotion Association CASNational Key R&D Program of China No.2018 YFA0404704。
文摘The Xinjiang Astronomical Observatory Data Center faces issues related to delay-affected services. As a result, these services cannot be implemented in a timely manner due to the overloading of transmission links. In this paper, the software-defined network technology is applied to the Xinjiang Astronomical Observatory Data Center Network(XAODCN). Specifically, a novel reconfiguration method is proposed to realise the software-defined Xinjiang Astronomical Observatory Data Center Network(SDXAO-DCN), and a network model is constructed. To overcome the congestion problem, a traffic load-balancing algorithm is designed for fast transmission of the service traffic by combining three factors: network structure, congestion level and transmission service. The proposed algorithm is compared with current commonly load-balancing algorithms which are used in data center to verify its efficiency. Simulation experiments show that the algorithm improved transmission performance and transmission quality for the SDXAO-DCN.
基金the Romanian Ministry of Education and Research for financing the projects:“The realization of 3D geological/geophysical models for the characterization of some areas of economic and scientific interest in Romania”,with Contract No.49N/2019“Institutional capacities and services for research,monitoring and forecasting of risks in extra-atmospheric space”,acronym SAFESPACE,Contract No.16PCCDI/2018,within PNCDIII.
文摘Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform the processing and analysis of geomagnetic parameters through different spectral,statistical and correlation methods.All these parameters are included in the geomagnetic database on server.The web interface for the database meets the different needs of handling the data collected,raw or processed.The server-side programming language used for design is php.This allow us to select different periods for which access to stored data,required for different search filters and different parameters or data from different time periods can be compared.For a more in-depth analysis of the stored data,through JavaScript programming language graphs for different parameters can be drawn.Access to the web interface can be done with or without authentication,depending on the need to ensure the security of certain data collected,stored and processed.The applications are scalable for different devices that will access it:mobile,tablets,laptops or desktops.
文摘The NCU (National Central University) Lu Lin Observatory (Fig. 1) is located at Mt. Front Lu Lin, 120°52′25″E and 23°28′07″N, a 2862 m peak in the Yu Shan National Park. The construction of Lu Lin Observatory was finished on January 14, 1999. The initial study of Lu Lin site was started since late 1989. Later on, a three year project was founded by the National Science Council (NSC) which supported the development of a modern seeing monitor for this site survey study from 1990 through 1993. The average seeing of Lu Lin site is about 1.39 arc second with average 200 clear nights annually. The sky background of this site is 20.72 mag/arcsec 2 in V band and 21.22 mag/arcsec 2 in B band. The Lu Lin observatory is developed for both research and education activity. A homemade 76 cm Super Light Telescope (SLT) and three TAOS’s 50 cm robotic telescopes will be the two major research facilities. The SLT is expected to be operated in the fall of 1999. We are proposing a pilot program to perform SLT observations of time varying astrophysical objects exploiting the unique geophysical location (e. g. time and longitudinal coverage) of Taiwan at the Western Pacific Rim in such topics of emerging interest. The TAOS’s telescopes will be installed in the late 1999 for the survey work of Kuiper Belt Objects. A wireless T1 Network system will also be build up for future remote observation.
文摘A 61 element adaptive optical system has been preliminary tested in the Coudé path of the 1 2m telescope at the Yunnan observatory this year. The whole system will be fully operated next year. This paper describes the AO system performances and its first experiment results, and the possible astronomical research topics.
文摘We carried out spectroscopic observations of several supernovae with 1 01m telescope at Bisei Astronomical Observatory, in order to investigate the type and characteristics soon after the discovery. Most of the observed supernovae were of type Ia. We present here some examples of the spectra and describe the necessity of the follow up observation site in East Asia.
