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
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
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
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
VOFilter is an XML based filter developed by the Chinese Virtual Observatory project to transform tabular data files from VOTable format into OpenDocument format. VOTable is an XML format defined for the exchange of t...VOFilter is an XML based filter developed by the Chinese Virtual Observatory project to transform tabular data files from VOTable format into OpenDocument format. VOTable is an XML format defined for the exchange of tabular data in the context of the Virtual Observatory (VO). It is the first Proposed Recommendation defined by International Virtual Observatory Alliance, and has obtained wide support from both the VO community and many Astronomy projects. OpenOffice.org is a mature, open source, and front office application suite with the advantage of native support of industrial standard OpenDocument XML file format. Using the VOFilter, VOTable files can be loaded in OpenOffice.org Calc, a spreadsheet application, and then displayed and analyzed as other spreadsheet files. Here, the VOFilter acts as a connector, bridging the coming VO with current industrial office applications. We introduce Virtual Observatory and technical background of the VOFilter. Its workflow, installation and usage are presented. Existing problems and limitations are also discussed together with the future development plans.展开更多
On August 20,2017,Chinese Vice Premier and State Councilor LIU Yandong paid a visit to Ali Observatory in west Tibet,which is located at 5,100 meters above sea level and a decade-long endeavor of the National Astronom...On August 20,2017,Chinese Vice Premier and State Councilor LIU Yandong paid a visit to Ali Observatory in west Tibet,which is located at 5,100 meters above sea level and a decade-long endeavor of the National Astronomical Observatories,Chinese Academy of Sciences(NAOC).During her visit,LIU exchanged with great interest with CAS President BAI Chunli and scientists,technicians and officials on the site.NAOC Director YAN Jun,Director of the Institute of High Energy Physics WANG Yifang and Vice President展开更多
Affiliation unit: Urumqi Astronomic Observatory, CAS Mainresearch field and disciplinary orientations: Taking radio-astronomy as its main research field,the Station concentrates its efforts on radio-astrophysics, astr...Affiliation unit: Urumqi Astronomic Observatory, CAS Mainresearch field and disciplinary orientations: Taking radio-astronomy as its main research field,the Station concentrates its efforts on radio-astrophysics, astro-telemetry, astro-geodynamics and related techniques. The main research orientations are in the following aspects:展开更多
The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buc...The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape indices.The critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s formula.Several numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were performed.The results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical simulations.This formula can be extended to estimate the buckling capacity of water-drop-shaped pressure hulls.In addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping technique.Subsequently,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical analysis.The experimental results were consistent with the numerical results.The results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt end.This paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.展开更多
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 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.
基金Supported by the National Natural Science Foundation of China.
文摘VOFilter is an XML based filter developed by the Chinese Virtual Observatory project to transform tabular data files from VOTable format into OpenDocument format. VOTable is an XML format defined for the exchange of tabular data in the context of the Virtual Observatory (VO). It is the first Proposed Recommendation defined by International Virtual Observatory Alliance, and has obtained wide support from both the VO community and many Astronomy projects. OpenOffice.org is a mature, open source, and front office application suite with the advantage of native support of industrial standard OpenDocument XML file format. Using the VOFilter, VOTable files can be loaded in OpenOffice.org Calc, a spreadsheet application, and then displayed and analyzed as other spreadsheet files. Here, the VOFilter acts as a connector, bridging the coming VO with current industrial office applications. We introduce Virtual Observatory and technical background of the VOFilter. Its workflow, installation and usage are presented. Existing problems and limitations are also discussed together with the future development plans.
文摘On August 20,2017,Chinese Vice Premier and State Councilor LIU Yandong paid a visit to Ali Observatory in west Tibet,which is located at 5,100 meters above sea level and a decade-long endeavor of the National Astronomical Observatories,Chinese Academy of Sciences(NAOC).During her visit,LIU exchanged with great interest with CAS President BAI Chunli and scientists,technicians and officials on the site.NAOC Director YAN Jun,Director of the Institute of High Energy Physics WANG Yifang and Vice President
文摘Affiliation unit: Urumqi Astronomic Observatory, CAS Mainresearch field and disciplinary orientations: Taking radio-astronomy as its main research field,the Station concentrates its efforts on radio-astrophysics, astro-telemetry, astro-geodynamics and related techniques. The main research orientations are in the following aspects:
基金financially supported by the National Natural Science Foundation of China(Grant Nos.52071160 and 52071203)the 333-Key-Industry Talent Project of Jiangsu Scientific Committee(Grant No.JTO 2022-21).
文摘The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape indices.The critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s formula.Several numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were performed.The results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical simulations.This formula can be extended to estimate the buckling capacity of water-drop-shaped pressure hulls.In addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping technique.Subsequently,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical analysis.The experimental results were consistent with the numerical results.The results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt end.This paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.