Winter coastal upwelling off northwest Borneo in the South China Sea （SCS） is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem- b...Winter coastal upwelling off northwest Borneo in the South China Sea （SCS） is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem- ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans- port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek- man transport is two times larger than Ekman pumping in January and February. Under the influence of E1 Nino-Southern Oscillation （ENSO）, the upwelling shows remarkable interannual variability： during winter of El Nino （La Nina） years, an anticyclonic （a cyclonic） wind anomaly is established in the SCS, which behaves a northeasterly （southwesterly） anomaly and a positive （negative） wind stress curl anomaly off the north- west Borneo coast, enhancing （reducing） the upwelling and causing anomalous surface cooling （warming） and higher （lower） chlorophyll concentration. The sea surface temperature anomaly （SSTA） associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.展开更多
Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal ...Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning layer.To address this issue,this study proposes a safe motion planning and control(SMPAC)framework for AVs.For the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller conservatism.For the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is proposed.The safety sets provide the basis for the subsequent evaluation and ranking of the generated trajectories.An efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the SMPAC.The result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.展开更多
Diabetes is a pervasive and serious global health issue.According to the International Diabetes Federation report,463 million adults worldwide were living with diabetes in 2019,and this number is projected to reach 70...Diabetes is a pervasive and serious global health issue.According to the International Diabetes Federation report,463 million adults worldwide were living with diabetes in 2019,and this number is projected to reach 700 million in 2045^([1]).展开更多
AIM:To compare efficacy of combined lamivudine(LAM)and adefovir dipivoxil(ADV)therapy with that of entecavir(ETV)monotherapy for hepatitis B virus(HBV)-related decompensated liver cirrhosis.METHODS:A total of 120 na v...AIM:To compare efficacy of combined lamivudine(LAM)and adefovir dipivoxil(ADV)therapy with that of entecavir(ETV)monotherapy for hepatitis B virus(HBV)-related decompensated liver cirrhosis.METHODS:A total of 120 na ve patients with HBVrelated decompensated cirrhosis participated in this study.Sixty patients were treated with combined LAM and ADV therapy(LAM+ADV group),while the other60 were treated with ETV monotherapy(ETV group)for two years.Tests for liver and kidney function,alpha-fetoprotein,HBV serum markers,HBV DNA load,prothrombin time(PT),and ultrasonography or computed tomography scan of the liver were performed every1 to 3 mo.Repeated measure ANOVA and theχ2test were performed to compare the efficacy,side effects,and the cumulative survival rates at 48 and 96 wk.RESULTS:Forty-five patients in each group were observed for 96 wk.No significant differences in HBV DNA negative rates and alanine aminotransferase(ALT)normalization rates at weeks 48(χ2=2.12 and 2.88)and96(χ2=3.21 and 3.24)between the two groups were observed.Hepatitis B e antigen seroconversion rate in the LAM+ADV group at week 96 was significantly higher in the ETV group(43.5%vs 36.4%,χ2=4.09,P<0.05).Viral breakthrough occurred in 2 cases(4.4%)by week 48 and in 3 cases(6.7%)by week 96 in the LAM+ADV group,and no viral mutation was detected.In the ETV group,viral breakthrough occurred in 1 case(2.2%)at the end of week 96.An increase in albumin(F=18.9 and 17.3),decrease in total bilirubin and in ALT(F=16.5,17.1 and 23.7,24.8),reduced PT(F=22.7 and 24.5),and improved Child-Turcotte-Pugh and the model for end-stage liver disease scores(F=18.5,17.8,and 24.2,23.8)were observed in both groups.The cumulative rates of mortality and liver transplantation were 16.7%(10/60)and 18.3%(11/60)in the LAM+ADV and ETV groups,respectively.CONCLUSION:Both LAM+ADV combination therapy and ETV monotherapy can effectively inhibit HBV replication,improve liver function,and decrease mortality.展开更多
Tropical cyclones （TCs） formed in the Northwest Pacific Ocean （NWP） can cross the South China Sea （SCS） sometimes. It is found that the TC tracks in the SCS in November are shifted to the north after 1980 compar...Tropical cyclones （TCs） formed in the Northwest Pacific Ocean （NWP） can cross the South China Sea （SCS） sometimes. It is found that the TC tracks in the SCS in November are shifted to the north after 1980 compared with those before 1980. Both data analyses and numerical simulations show that the surface warming in the SCS may contribute to this more northward shift. The warming produces a cyclonic atmosphere circulation anomaly in the northwestern SCS and an associated southerly in the central SCS steering the TCs to the north.展开更多
Due to orographic blockage, a weak wind wake occurs in summer off northeast Vietnam in the South China Sea. Under the wind wake, warm water is observed from both high-resolution satellite data and hydrographic observa...Due to orographic blockage, a weak wind wake occurs in summer off northeast Vietnam in the South China Sea. Under the wind wake, warm water is observed from both high-resolution satellite data and hydrographic observations. The wake of warm water forms in June, continues to mature in July and August, starts to decay in September, and disappears in October. The warm water wake also shows robust diurnal variation – it intensifies during the day and weakens in the night. Warm water wakes can be generated through wind-induced mixing and thermal（latent heat flux） processes. In this paper, a mixed layer model is used to evaluate the relative importance of the two processes on seasonal and diurnal timescales, respectively. The results demonstrate that thermal processes make a greater contribution to the wake than wind-induced mixing processes on a seasonal timescale, while the warm water wake is dominated by wind-induced mixing processes on a diurnal timescale.展开更多
Interannual variability of thermal front west of Luzon Island during the winter of 1993-2013 is examined with the method of singular value decomposition （SVD） and a suite of satellite measurements in this paper. It ...Interannual variability of thermal front west of Luzon Island during the winter of 1993-2013 is examined with the method of singular value decomposition （SVD） and a suite of satellite measurements in this paper. It is found that both the area and intensity of the thermal front west of Luzon Island show apparent interannual variability. Further study based on SVD shows that the interannual variability of the thermal front is highly associated with E1 Nifio and Southern Oscillation （ENSO）, and the correlation coefficient between Nifio3.4 index and the first Principal Component （PC1） of thermal front can reach -0.65. The mechanism can be described as follows. In E1 Nifio （La Nifia） years, the East Asian winter monsoon （EAWM） is weakened （enhanced）, inducing weaker （stronger） local wind stress curl （WSC） west of Luzon Island, and resulting in weakened （enhanced） Luzon cold eddy, which finally leads to the weakening （enhancement） of the thermal front.展开更多
Rammasun intensified rapidly from tropical storm to super typhoon in the northern South China Sea（NSCS）before its landfall on Hainan Island. Analysis of observed data shows that the anomalous ocean upper layer warm ...Rammasun intensified rapidly from tropical storm to super typhoon in the northern South China Sea（NSCS）before its landfall on Hainan Island. Analysis of observed data shows that the anomalous ocean upper layer warm water（WW） is important to the rapid intensification of Rammasun. During the period of Rammasun, sea surface temperature（SST） in the NSCS was much warmer than the climatological SST. The anomalous WW supplied more energy to Rammasun, resulting in its rapid intensification. Numerical simulations further confirm that the NSCS WW plays an important role in the rapid intensification of Rammasun. As the WW is removed, the intensification of Rammasun is only 25 h Pa, which is 58.1% of that in the original SST-forced run.展开更多
Neuromorphic photonic computing has emerged as a competitive computing paradigm to overcome the bottlenecks of the von-Neumann architecture.Linear weighting and nonlinear spike activation are two fundamental functions...Neuromorphic photonic computing has emerged as a competitive computing paradigm to overcome the bottlenecks of the von-Neumann architecture.Linear weighting and nonlinear spike activation are two fundamental functions of a photonic spiking neural network(PSNN).However,they are separately implemented with different photonic materials and devices,hindering the large-scale integration of PSNN.Here,we propose,fabricate and experimentally demonstrate a photonic neuro-synaptic chip enabling the simultaneous implementation of linear weighting and nonlinear spike activation based on a distributed feedback(DFB)laser with a saturable absorber(DFB-SA).A prototypical system is experimentally constructed to demonstrate the parallel weighted function and nonlinear spike activation.Furthermore,a fourchannel DFB-SA laser array is fabricated for realizing matrix convolution of a spiking convolutional neural network,achieving a recognition accuracy of 87%for the MNIST dataset.The fabricated neuro-synaptic chip offers a fundamental building block to construct the large-scale integrated PSNN chip.展开更多
基金The National Natural Science Foundation of China under contract No.91128212the National Natural Science Foundation of China under contract No.41306024+3 种基金the National Basic Research Program of China under contract No.2013CB430301the National Science Fund of China for Distinguished Young Scholars(NSFDYS)under contract No.41125019the Project of Global Change and Air-Sea Interaction under con-tract No.GASI-03-01-03-03the Basic Research Program of Second Institute of Oceanography,State Oceanic Administration of China under contract No.JT1301
文摘Winter coastal upwelling off northwest Borneo in the South China Sea （SCS） is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem- ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans- port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek- man transport is two times larger than Ekman pumping in January and February. Under the influence of E1 Nino-Southern Oscillation （ENSO）, the upwelling shows remarkable interannual variability： during winter of El Nino （La Nina） years, an anticyclonic （a cyclonic） wind anomaly is established in the SCS, which behaves a northeasterly （southwesterly） anomaly and a positive （negative） wind stress curl anomaly off the north- west Borneo coast, enhancing （reducing） the upwelling and causing anomalous surface cooling （warming） and higher （lower） chlorophyll concentration. The sea surface temperature anomaly （SSTA） associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.
基金supported by the National Natural Science Foundation of China(51875061)China Scholarship Council(202206050107)。
文摘Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning layer.To address this issue,this study proposes a safe motion planning and control(SMPAC)framework for AVs.For the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller conservatism.For the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is proposed.The safety sets provide the basis for the subsequent evaluation and ranking of the generated trajectories.An efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the SMPAC.The result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.
基金The Central Universities,Lanzhou University,China [lzujbky-2021-ey07]the innovative talent project of Lanzhou city[Lanzhou science and technology bureau, 2022-RC-42 to BL]Gansu Province Young Doctoral Fund Project [2021QB005]
文摘Diabetes is a pervasive and serious global health issue.According to the International Diabetes Federation report,463 million adults worldwide were living with diabetes in 2019,and this number is projected to reach 700 million in 2045^([1]).
基金Supported by the National Key Program for Infectious Diseases of China to Yang YD,2013ZX1000200112th Five-Year Significant New Drugs Creation Plan of the Ministry of Science and Technology of China toYangYD,2011ZX09302-003-03
文摘AIM:To compare efficacy of combined lamivudine(LAM)and adefovir dipivoxil(ADV)therapy with that of entecavir(ETV)monotherapy for hepatitis B virus(HBV)-related decompensated liver cirrhosis.METHODS:A total of 120 na ve patients with HBVrelated decompensated cirrhosis participated in this study.Sixty patients were treated with combined LAM and ADV therapy(LAM+ADV group),while the other60 were treated with ETV monotherapy(ETV group)for two years.Tests for liver and kidney function,alpha-fetoprotein,HBV serum markers,HBV DNA load,prothrombin time(PT),and ultrasonography or computed tomography scan of the liver were performed every1 to 3 mo.Repeated measure ANOVA and theχ2test were performed to compare the efficacy,side effects,and the cumulative survival rates at 48 and 96 wk.RESULTS:Forty-five patients in each group were observed for 96 wk.No significant differences in HBV DNA negative rates and alanine aminotransferase(ALT)normalization rates at weeks 48(χ2=2.12 and 2.88)and96(χ2=3.21 and 3.24)between the two groups were observed.Hepatitis B e antigen seroconversion rate in the LAM+ADV group at week 96 was significantly higher in the ETV group(43.5%vs 36.4%,χ2=4.09,P<0.05).Viral breakthrough occurred in 2 cases(4.4%)by week 48 and in 3 cases(6.7%)by week 96 in the LAM+ADV group,and no viral mutation was detected.In the ETV group,viral breakthrough occurred in 1 case(2.2%)at the end of week 96.An increase in albumin(F=18.9 and 17.3),decrease in total bilirubin and in ALT(F=16.5,17.1 and 23.7,24.8),reduced PT(F=22.7 and 24.5),and improved Child-Turcotte-Pugh and the model for end-stage liver disease scores(F=18.5,17.8,and 24.2,23.8)were observed in both groups.The cumulative rates of mortality and liver transplantation were 16.7%(10/60)and 18.3%(11/60)in the LAM+ADV and ETV groups,respectively.CONCLUSION:Both LAM+ADV combination therapy and ETV monotherapy can effectively inhibit HBV replication,improve liver function,and decrease mortality.
基金The National Basic Research Program(973 Program)of China under contract Nos 2013CB430301,2013CB430302,2012CB955601,and 2012CB955601the National Science and Technology Major Project under contract No.2016ZX05057015+2 种基金the National Natural Science Foundation of China under contract Nos 41276018 and 41376038the Global Air-Sea Interaction Project of State Oceanic Administration under contract Nos GASI-03-01-01-09 and GASI-03-01-01-02the National program on Global Change and Air-Sea interaction under contract Nos GASI-IPOVAI-01-05 and GASI-IPOVAI-04
文摘Tropical cyclones （TCs） formed in the Northwest Pacific Ocean （NWP） can cross the South China Sea （SCS） sometimes. It is found that the TC tracks in the SCS in November are shifted to the north after 1980 compared with those before 1980. Both data analyses and numerical simulations show that the surface warming in the SCS may contribute to this more northward shift. The warming produces a cyclonic atmosphere circulation anomaly in the northwestern SCS and an associated southerly in the central SCS steering the TCs to the north.
基金The National Science Fund of China for Distinguished Young Scholars(NSFDYS)under contract No.41125019the National Basic Research Program of China under contract Nos 2012CB955601 and 2013CB430301the Basic Research Program of Second Institute of Oceanography,State Oceanic Administration of China under contract No.JT1301
文摘Due to orographic blockage, a weak wind wake occurs in summer off northeast Vietnam in the South China Sea. Under the wind wake, warm water is observed from both high-resolution satellite data and hydrographic observations. The wake of warm water forms in June, continues to mature in July and August, starts to decay in September, and disappears in October. The warm water wake also shows robust diurnal variation – it intensifies during the day and weakens in the night. Warm water wakes can be generated through wind-induced mixing and thermal（latent heat flux） processes. In this paper, a mixed layer model is used to evaluate the relative importance of the two processes on seasonal and diurnal timescales, respectively. The results demonstrate that thermal processes make a greater contribution to the wake than wind-induced mixing processes on a seasonal timescale, while the warm water wake is dominated by wind-induced mixing processes on a diurnal timescale.
基金The Distinguished Young Scholars of National Natural Science Foundation of China under contract Nos 41125019 and 41306024the National Basic Research Program(973 Program) of China under contract No.2013CB430301+1 种基金the Basic Scientific Research Fund of Second Institute of Oceanography,State Oceanic Administration under contract No.JT1301the National Natural Science Foundation under contract No.41476002
文摘Interannual variability of thermal front west of Luzon Island during the winter of 1993-2013 is examined with the method of singular value decomposition （SVD） and a suite of satellite measurements in this paper. It is found that both the area and intensity of the thermal front west of Luzon Island show apparent interannual variability. Further study based on SVD shows that the interannual variability of the thermal front is highly associated with E1 Nifio and Southern Oscillation （ENSO）, and the correlation coefficient between Nifio3.4 index and the first Principal Component （PC1） of thermal front can reach -0.65. The mechanism can be described as follows. In E1 Nifio （La Nifia） years, the East Asian winter monsoon （EAWM） is weakened （enhanced）, inducing weaker （stronger） local wind stress curl （WSC） west of Luzon Island, and resulting in weakened （enhanced） Luzon cold eddy, which finally leads to the weakening （enhancement） of the thermal front.
基金The National Basic Research Program(973 Program)of China under contract Nos 2013CB430301 and 2013CB430302the National Natural Science Foundation of China under contract Nos 41306024 and 41276018+3 种基金the Scientific Research Fund of the Second Institute of Oceanography,State Oceanic Administration of China under contract Nos JT1301 and JG1416the Fundamental Research Funds for the Central Universities under contract No.2013B25914the Jiangsu Postgraduate Scientific Research and Innovation Projects under contract No.2013B25914the Project of Global Change and Air-Sea interaction under contract No.GASI-03-IPOVAI-04
文摘Rammasun intensified rapidly from tropical storm to super typhoon in the northern South China Sea（NSCS）before its landfall on Hainan Island. Analysis of observed data shows that the anomalous ocean upper layer warm water（WW） is important to the rapid intensification of Rammasun. During the period of Rammasun, sea surface temperature（SST） in the NSCS was much warmer than the climatological SST. The anomalous WW supplied more energy to Rammasun, resulting in its rapid intensification. Numerical simulations further confirm that the NSCS WW plays an important role in the rapid intensification of Rammasun. As the WW is removed, the intensification of Rammasun is only 25 h Pa, which is 58.1% of that in the original SST-forced run.
基金financial supports from National Key Research and Development Program of China (2021YFB2801900,2021YFB2801901,2021YFB2801902,2021YFB2801904)National Natural Science Foundation of China (No.61974177)+1 种基金National Outstanding Youth Science Fund Project of National Natural Science Foundation of China (62022062)The Fundamental Research Funds for the Central Universities (QTZX23041).
文摘Neuromorphic photonic computing has emerged as a competitive computing paradigm to overcome the bottlenecks of the von-Neumann architecture.Linear weighting and nonlinear spike activation are two fundamental functions of a photonic spiking neural network(PSNN).However,they are separately implemented with different photonic materials and devices,hindering the large-scale integration of PSNN.Here,we propose,fabricate and experimentally demonstrate a photonic neuro-synaptic chip enabling the simultaneous implementation of linear weighting and nonlinear spike activation based on a distributed feedback(DFB)laser with a saturable absorber(DFB-SA).A prototypical system is experimentally constructed to demonstrate the parallel weighted function and nonlinear spike activation.Furthermore,a fourchannel DFB-SA laser array is fabricated for realizing matrix convolution of a spiking convolutional neural network,achieving a recognition accuracy of 87%for the MNIST dataset.The fabricated neuro-synaptic chip offers a fundamental building block to construct the large-scale integrated PSNN chip.
