The Taklimakan Desert, the world's second largest desert, plays an important role in regional climate change. Previousstudies on its spatial temperature features suffered from sparse conventional detection data, b...The Taklimakan Desert, the world's second largest desert, plays an important role in regional climate change. Previousstudies on its spatial temperature features suffered from sparse conventional detection data, but the Atmospheric InfraredSounder (AIRS) provides excellent temperature retrievals with high spatiotemporal resolution. Validation of AIRS temperatureretrievals over desert regions with high land-surface emissivity, the key contributor to inversion error, is essential beforeusing these data in regional weather/climate modeling. This paper examines the correlation coefficients, root meansquare error (RMSE) and mean BIAS between AIRS-retrieved atmospheric temperature data and radiosonde observations(RAOBs) in the Taklimakan Desert hinterland and oases in the morning and at dusk. Firstly, the AIRS retrievals are consistentwith RAOBs and are more consistent in the morning than at dusk. The consistency is better over a small-scale desert oasisthan over a large-scale oasis in the morning and exhibits the opposite trend at dusk. The correlation coefficient over thehinterland is high in the morning but negative at dusk due to high desert-surface emissivity. Second, the RMSEs, which areall smaller than 3 K, are generally higher over desert sites than over oasis sites and slightly lower over a small-scale oasisthan over a large-scale oasis in the morning. At dusk, the RMSEs are higher over desert sites than over oases and slightlyhigher over a small-scale oasis than over a large-scale oasis. Furthermore, the RMSEs are generally higher in the morningthan at dusk over a large-scale oasis and lower in the morning than at dusk over a small-scale oasis. Third, the absolutemean BIAS values are mostly lower than 1 K. In the morning, relative to RAOB temperatures, the retrieval temperaturesare higher over desert sites but lower over oasis sites. At dusk, the retrieval temperatures are lower than RAOB temperaturesover both desert and oasis sites. The retrieval temperatures are higher than RAOB temperatures over desert sites inthe morning but slightly lower at dusk. Most absolute mean BIAS values are higher in the morning than at dusk overboth oasis and desert sites. Finally, the consistency between the AIRS and RAOB temperature data is high from 700 hPato 100 hPa in the morning and from 700 hPa to 300 hPa at dusk. The difference between the AIRS and RAOB temperaturedata is generally higher in the morning than that at dusk. The RMSE differences between the AIRS and RAOB data areslightly lower in the morning than at dusk and are lower in the middle layers between 700 hPa and 150 hPa than in the layersabove 150 hPa during both the morning and night. The BIAS is lower in the morning than at dusk below 300 hPabut higher in the upper layers. Moreover, the BIAS value is positive in the middle layers between 500 hPa and 150 hPaand negative at other levels at both times. Generally, the AIRS retrieval temperatures are reliable and can be used in furtherstudies in the Taklimakan Desert.展开更多
The Infrared Atmospheric Sounding Interferometer (IASI) is a new-generation ultraspectral atmospheric sounding instrument mounted on the MetOp-A, the first operational polar-orbiting satellite developed by the Europea...The Infrared Atmospheric Sounding Interferometer (IASI) is a new-generation ultraspectral atmospheric sounding instrument mounted on the MetOp-A, the first operational polar-orbiting satellite developed by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). It is an ultrahigh spectral-resolution atmospheric detector which can detect atmospheric chemical composition, temperature, and humidity profiles with high accuracy and resolution. In the present study, through comparative analyses of the similarities and differences between the IASI and the radiosonde observation (RAOB) water vapor data, and between the IASI and the Aqua-AIRS water vapor retrievals, a detailed and systematic assessment of the credibility of the IASI water vapor retrievals over the plateau region was made. A comparison of the IASI retrievals with the AIRS retrievals and the RAOB measurements over the Tibetan Plateau revealed that the IASI retrieval data are reliable and can be used for conducting further studies.展开更多
Teleoperation rendezvous and docking can be used as a backup for autonomous rendezvous and docking（RVD） for an unmanned spacecraft when the autonomous system is failure or for guiding the chaser docking with an unco...Teleoperation rendezvous and docking can be used as a backup for autonomous rendezvous and docking（RVD） for an unmanned spacecraft when the autonomous system is failure or for guiding the chaser docking with an uncooperative target.The theoretical model for analyzing the handling qualities in teleoperation RVD process is established based on the previous studies conducted by National Aeronautics and Space Administration（NASA）.The predictive factor is introduced to describe the pilot＇s predictive ability in the teleoperation tasks with time delay,which interrelates with the skills of a pilot and the predictive assist approach used in the tasks such as the predictive display method.Based on the semi-physical simulation system in our laboratory,900 experiments at two levels of time delay are carried out by 18 volunteers for validating the established model.The experimental results demonstrate the correctness of the theoretical model and indicate that a skilled pilot has a predictive ability of approximately 0.9 in teleoperation RVD tasks.The theoretical analysis shows that the handling qualities are greatly affected by the time delay and the predictive factor,and it is impossible to achieve a teleoperation RVD task for the skilled pilot when the time delay is larger than 9.0 s.展开更多
The water quality grades of phosphate（PO4-P） and dissolved inorganic nitrogen（DIN） are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validat...The water quality grades of phosphate（PO4-P） and dissolved inorganic nitrogen（DIN） are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging（SK） interpolation is applied to DIN and ordinary Kriging（OK） interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang（Yangtze River） Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater.展开更多
The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineur...The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.展开更多
文摘The Taklimakan Desert, the world's second largest desert, plays an important role in regional climate change. Previousstudies on its spatial temperature features suffered from sparse conventional detection data, but the Atmospheric InfraredSounder (AIRS) provides excellent temperature retrievals with high spatiotemporal resolution. Validation of AIRS temperatureretrievals over desert regions with high land-surface emissivity, the key contributor to inversion error, is essential beforeusing these data in regional weather/climate modeling. This paper examines the correlation coefficients, root meansquare error (RMSE) and mean BIAS between AIRS-retrieved atmospheric temperature data and radiosonde observations(RAOBs) in the Taklimakan Desert hinterland and oases in the morning and at dusk. Firstly, the AIRS retrievals are consistentwith RAOBs and are more consistent in the morning than at dusk. The consistency is better over a small-scale desert oasisthan over a large-scale oasis in the morning and exhibits the opposite trend at dusk. The correlation coefficient over thehinterland is high in the morning but negative at dusk due to high desert-surface emissivity. Second, the RMSEs, which areall smaller than 3 K, are generally higher over desert sites than over oasis sites and slightly lower over a small-scale oasisthan over a large-scale oasis in the morning. At dusk, the RMSEs are higher over desert sites than over oases and slightlyhigher over a small-scale oasis than over a large-scale oasis. Furthermore, the RMSEs are generally higher in the morningthan at dusk over a large-scale oasis and lower in the morning than at dusk over a small-scale oasis. Third, the absolutemean BIAS values are mostly lower than 1 K. In the morning, relative to RAOB temperatures, the retrieval temperaturesare higher over desert sites but lower over oasis sites. At dusk, the retrieval temperatures are lower than RAOB temperaturesover both desert and oasis sites. The retrieval temperatures are higher than RAOB temperatures over desert sites inthe morning but slightly lower at dusk. Most absolute mean BIAS values are higher in the morning than at dusk overboth oasis and desert sites. Finally, the consistency between the AIRS and RAOB temperature data is high from 700 hPato 100 hPa in the morning and from 700 hPa to 300 hPa at dusk. The difference between the AIRS and RAOB temperaturedata is generally higher in the morning than that at dusk. The RMSE differences between the AIRS and RAOB data areslightly lower in the morning than at dusk and are lower in the middle layers between 700 hPa and 150 hPa than in the layersabove 150 hPa during both the morning and night. The BIAS is lower in the morning than at dusk below 300 hPabut higher in the upper layers. Moreover, the BIAS value is positive in the middle layers between 500 hPa and 150 hPaand negative at other levels at both times. Generally, the AIRS retrieval temperatures are reliable and can be used in furtherstudies in the Taklimakan Desert.
基金supported by the State Key Basic Research Development Program(Grant No.2012CB417204)the R&D Special Fund for Public Welfare Industry(Meteorology) by the Ministry of Finance and the Ministry of Science and Technology(Grant Nos.GYHY200806007,GYHY201006014,and GYHY201206039)the National Natural Science Foundation(Grant Nos.41175064,40875022,and 40633016)
文摘The Infrared Atmospheric Sounding Interferometer (IASI) is a new-generation ultraspectral atmospheric sounding instrument mounted on the MetOp-A, the first operational polar-orbiting satellite developed by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). It is an ultrahigh spectral-resolution atmospheric detector which can detect atmospheric chemical composition, temperature, and humidity profiles with high accuracy and resolution. In the present study, through comparative analyses of the similarities and differences between the IASI and the radiosonde observation (RAOB) water vapor data, and between the IASI and the Aqua-AIRS water vapor retrievals, a detailed and systematic assessment of the credibility of the IASI water vapor retrievals over the plateau region was made. A comparison of the IASI retrievals with the AIRS retrievals and the RAOB measurements over the Tibetan Plateau revealed that the IASI retrieval data are reliable and can be used for conducting further studies.
文摘Teleoperation rendezvous and docking can be used as a backup for autonomous rendezvous and docking（RVD） for an unmanned spacecraft when the autonomous system is failure or for guiding the chaser docking with an uncooperative target.The theoretical model for analyzing the handling qualities in teleoperation RVD process is established based on the previous studies conducted by National Aeronautics and Space Administration（NASA）.The predictive factor is introduced to describe the pilot＇s predictive ability in the teleoperation tasks with time delay,which interrelates with the skills of a pilot and the predictive assist approach used in the tasks such as the predictive display method.Based on the semi-physical simulation system in our laboratory,900 experiments at two levels of time delay are carried out by 18 volunteers for validating the established model.The experimental results demonstrate the correctness of the theoretical model and indicate that a skilled pilot has a predictive ability of approximately 0.9 in teleoperation RVD tasks.The theoretical analysis shows that the handling qualities are greatly affected by the time delay and the predictive factor,and it is impossible to achieve a teleoperation RVD task for the skilled pilot when the time delay is larger than 9.0 s.
基金The National Natural Science Fundation of China under contract Nos 41376190,41271404,41531179,41421001 and41601425the Open Funds of the Key Laboratory of Integrated Monitoring and Applied Technologies for Marin Harmful Algal Blooms,SOA under contract No.MATHA201120204+1 种基金the Scientific Research Project of Shanghai Marine Bureau under contract No.Hu Hai Ke2016-05the Ocean Public Welfare Scientific Research Project,State Oceanic Administration of the People's Republic of China under contract Nos 201305027 and 201505008
文摘The water quality grades of phosphate（PO4-P） and dissolved inorganic nitrogen（DIN） are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging（SK） interpolation is applied to DIN and ordinary Kriging（OK） interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang（Yangtze River） Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater.
基金supported by the National Important Novel Medicine Research Project (2012ZX09304010, 2013ZX09102062)the National Natural Science Foundation of China (31270849)
文摘The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.
