At present,the growth momentum of the world economy is clearly insufficient,and faced with many unstable,uncertain and unpredictable factors,the world economy is generally on a downward path.From the perspective of tr...At present,the growth momentum of the world economy is clearly insufficient,and faced with many unstable,uncertain and unpredictable factors,the world economy is generally on a downward path.From the perspective of trend changes,the world economy will still be in the process of reshaping its growth momentum in 2024,with positive factors accumulating but downward pressure remaining.展开更多
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua...This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.展开更多
Based on NCEP reanalysis data,EDAS data and ground observation data,the causes of a strong sandstorm process in Ulanqab City from March 14 to 15,2021 were analyzed.The analysis shows that"3.15"sandstorm,a sa...Based on NCEP reanalysis data,EDAS data and ground observation data,the causes of a strong sandstorm process in Ulanqab City from March 14 to 15,2021 were analyzed.The analysis shows that"3.15"sandstorm,a sandstorm process accompanied by northwest gale behind the front,was caused by strong cold air in the north.In the early stage,the Mongolian cyclone resulted in the increase of temperature and decrease of pressure on the ground.When a strong surface cold high pressure at the rear of the cyclone invaded the city,a strong pressure gradient between high and low pressure provided dynamic conditions for the sandstorm outbreak.The transit of the surface cold front was the sign of the sandstorm outbreak,and the downward transmission of momentum at high altitudes increased the wind speed near the surface.展开更多
ABSTRACT Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency(LOCE)for planar perovskite light-emitting diodes(PeLEDs).In this work,we employ phenethylammonium iodide(PEAI)t...ABSTRACT Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency(LOCE)for planar perovskite light-emitting diodes(PeLEDs).In this work,we employ phenethylammonium iodide(PEAI)to trigger the Ostwald ripening for the downward recrystallization of perovskite,resulting in spontaneous formation of buried submicrocavities as light output coupler.The simulation suggests the buried submicrocavities can improve the LOCE from 26.8 to 36.2%for near-infrared light.Therefore,PeLED yields peak external quantum efficiency(EQE)increasing from 17.3%at current density of 114 mA cm^(−2)to 25.5%at current density of 109 mA cm^(−2)and a radiance increasing from 109 to 487 W sr^(−1)m^(−2)with low rolling-off.The turn-on voltage decreased from 1.25 to 1.15 V at 0.1 W sr^(−1)m^(−2).Besides,downward recrystallization process slightly reduces the trap density from 8.90×10^(15)to 7.27×10^(15)cm^(−3).This work provides a self-assembly method to integrate buried output coupler for boosting the performance of PeLEDs.展开更多
To analyze the pipeline response under permanent ground deformation,the evolution of resistance acting on the pipe during the vertical downward offset is an essential ingredient.However,the efficient simulation of pip...To analyze the pipeline response under permanent ground deformation,the evolution of resistance acting on the pipe during the vertical downward offset is an essential ingredient.However,the efficient simulation of pipe penetration into soil is challenging for the conventional finite element(FE)method due to the large deformation of the surrounding soils.In this study,the B-spline material point method(MPM)is employed to investigate the pipe-soil interaction during the downward movement of rigid pipes buried in medium and dense sand.To describe the density-and stress-dependent behaviors of sand,the J2-deformation type model with state-dependent dilatancy is adopted.The effectiveness of the model is demonstrated by element tests and biaxial compression tests.Afterwards,the pipe penetration process is simulated,and the numerical outcomes are compared with the physical model tests.The effects of pipe size and burial depth are investigated with an emphasis on the mobilization of the soil resistance and the failure mechanisms.The simulation results indicate that the bearing capacity formulas given in the guidelines can provide essentially reasonable estimates for the ultimate force acting on buried pipes,and the recommended value of yield displacement may be underestimated to a certain extent.展开更多
The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams.As a result,massive surface melting events of the ice shelf are occurring more frequen...The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams.As a result,massive surface melting events of the ice shelf are occurring more frequently,which puts the West Antarctica Ice Sheet at greater risk of degradation.This study shows the connection between surface melting and the prominent intrusion of warm and humid air flows from lower latitudes.By applying the Climate Feedback-Response Analysis Method(CFRAM),the temporal surge of the downward longwave(LW)fluxes over the surface of the Ross Ice Shelf(RIS)and adjacent regions are identified for four historically massive RIS surface melting events.The melting events are decomposed to identify which physical mechanisms are the main contributors.We found that intrusions of warm and humid airflow from lower latitudes are conducive to warm air temperature and water vapor anomalies,as well as cloud development.These changes exert a combined impact on the abnormal enhancement of the downward LW surface radiative fluxes,significantly contributing to surface warming and the resultant massive melting of ice.展开更多
Radiation is the direct energy source of the surface natural environment and the main driving force of climate change.It has increasingly become an important meteorological factor affecting the surface heat exchange a...Radiation is the direct energy source of the surface natural environment and the main driving force of climate change.It has increasingly become an important meteorological factor affecting the surface heat exchange and glacier mass balance,especially in the glacier changes of the Greenland Ice Sheet(Gr IS).Due to the harsh climatic conditions of Gr IS and sparse observed data,it has become an important way to obtain radiation data from reanalysis datasets.However,the applicability of these radiation data on Gr IS is uncertain and worth exploring.In this work,we evaluate five reanalysis datasets(the fifth generation of European Centre for Medium-Range Weather Forecasts(ERA5),European Centre for Medium-Range Weather Forecasts Interim Reanalysis(ERA-Interim),Japanese 55-year Reanalysis(JRA55),National Centers for Environmental Prediction Reanalysis II(NCEP2)and Modern-Era Retrospective analysis for Research and Applications,Version 2(MERRA-2))during 1997-2022 using observations from 26 Program for Monitoring the Greenland Ice Sheet(PROMICE)automatic weather stations(AWSs)and 3 K-transect AWSs on Gr IS.The conclusions are as follows:ERA5 has the best performances in downward shortwave radiation(SWD)as well as downward and upward longwave radiation(LWD and LWU),but the performance is not the best in upward shortwave radiation(SWU).Based on the radiation budget analysis with ERA5 during 1979-2022,the fluctuation of longwave radiation is greater than that of shortwave radiation.The seasonal variation of shortwave radiation is obvious,while that of longwave radiation is small.The increasing trend of longwave radiation may result from global warming,in which ice sheets absorb more solar radiation and the surface heats up significantly,emitting more LWU.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common malignant tumors in the world,which is seriously threatening the lives of patients.Due to the rapid development of the disease,patients were in the mid...BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common malignant tumors in the world,which is seriously threatening the lives of patients.Due to the rapid development of the disease,patients were in the middle and advanced stages at the time of diagnosis and missed the best time for treatment.With the development of minimally invasive medicine,interventional therapy for advanced HCC has achieved promising results.Transarterial chemoembolization(TACE)and transarterial radioembolization(TARE)are currently recognized as effective treatments.This study aimed to investigate the clinical value and safety of TACE alone and combined with TACE in the treatment of progression in patients with advanced HCC and to find a breakthrough for the early diagnosis and treatment of patients with advanced HCC.AIM To investigate the efficacy and safety of hepatic TACE and TARE in advanced descending hepatectomy.METHODS In this study,218 patients with advanced HCC who were treated in the Zhejiang Provincial People’s Hospital from May 2016 to May 2021 were collected.Of the patients,119 served as the control group and received hepatic TACE,99 served as the observation group and were treated with hepatic TACE combined with TARE.The patients in two groups were compared in terms of lesion inactivation,tumor nodule size,lipiodol deposition,serum alpha-fetoprotein(AFP)level in different periods,postoperative complications,1-year survival rate,and clinical symptoms such as liver pain,fatigue,and abdominal distension,and adverse reactions such as nausea and vomiting.RESULTS The observation group and the control group had good efficacy in treatment efficiency,reduction of tumor nodules,reduction of postoperative AFP value,reduction of postoperative complications,and relief of clinical symptoms.In addition,compared with the control group,the treatment efficiency,reduction of tumor nodules,reduction of AFP value,reduction of postoperative complications,and relief of clinical symptoms in the observation group were better than those in the TACE group alone.Patients in the TACE+TARE group had a higher 1-year survival rate after surgery,lipiodol deposition was significantly increased and the extent of tumor necrosis was expanded.The overall incidence of adverse reactions in the TACE+TARE group was lower than that in the TACE group,and the difference had statistical significance(P<0.05).CONCLUSION Compared with TACE alone,TACE combined with TARE is more effective in the treatment of patients with advanced HCC.It also improves postoperative survival rate,reduces adverse effects,and has a better safety profile.展开更多
The process of wafer polishing is known to be highly demanding,and even small deviations in the processing parameters can have a significant impact on the quality of the wafers obtained.During the process of wafer pol...The process of wafer polishing is known to be highly demanding,and even small deviations in the processing parameters can have a significant impact on the quality of the wafers obtained.During the process of wafer polishing,maintaining a constant pressure value applied by the polishing head is essential to achieve the desired flatness of the wafer.The accuracy of the downward pressure output by the polishing head is a crucial factor in producing flat wafers.In this paper,the uncertainty component of downward pressure is calculated and its measurement uncertainty is evaluated,and a method for calculating downward pressure uncertainty traceable to international basic unit is established.Therefore,the reliability of double side polishing machine has been significantly improved.展开更多
Faced with the impact of complex and changeable domestic and international situations and multiple factors exceeding expectations,China's textile industry has experienced weak market demand,high raw material cost,...Faced with the impact of complex and changeable domestic and international situations and multiple factors exceeding expectations,China's textile industry has experienced weak market demand,high raw material cost,more complex trade environment and significantly increased economic operating pressure since 2022.The growth rate of main economic indicators of the textile machinery industry continues to weaken,and the economic operation faces great downward pressure.展开更多
A nine-layer spectral atmospheric general circulation model is coupled to a twenty-layer global oceanic general circulation model with the“prediction-correction”monthly anomaly exchange scheme which has been propose...A nine-layer spectral atmospheric general circulation model is coupled to a twenty-layer global oceanic general circulation model with the“prediction-correction”monthly anomaly exchange scheme which has been proposed at the Institute of Atmospheric Physics (IAP). A forty-year integration of the coupled model shows that the CGCM is fairly successful in keeping a reasonable pattern of the modelled SST although most of the Pacific become warmer than those given by the uncoupled ocean model. The model tends to reach a more realistic state than the uncoupled one in terms of downward surface heat flux into ocean particularly in the equatorial Pacific region. Also, the model is capable to simulate interannual variability of sea surface temperature in tropical region.展开更多
The Markov process with discrete state and time is used to simulate the distribution of liquid flow in apacked column.The theoretical prediction agrees well with the experimental data.
A precipitation system developed continuously along the western coastline of the Korean Peninsula and created considerable precipitation both along the coast and inland on 26 July 2011. In this study, the causes for t...A precipitation system developed continuously along the western coastline of the Korean Peninsula and created considerable precipitation both along the coast and inland on 26 July 2011. In this study, the causes for this nearshore convective system are investigated from observations and the results of model experiments. Three-dimensional radar fields clearly show that a change of wind at the surface border played an important role in the development of the nearshore convection system. The simulation results, which are very similar to the observations, show that the surface border generated and maintained the convergence zone. The roughness change enhanced the convergence, and the interaction between the deepening cold pool and downward flow maintained the convergence zone. The surface mechanical discontinuity affected by the roughness change between sea and land formed the convergence (gradient of wind stress), which induced momentum transfer to the upper layer. The cold pool created a steep gradient of potential temperature and provided the reason for the propagated convergence zone with the downward flow. The maximum value of the surface change factor, which comprises the influencing factors for the long-lasting convective system, reflects the enhancement of the system at the coast.展开更多
Downward continuation is a key step in processing airborne geomagnetic data. However,downward continuation is a typically ill-posed problem because its computation is unstable; thus, regularization methods are needed ...Downward continuation is a key step in processing airborne geomagnetic data. However,downward continuation is a typically ill-posed problem because its computation is unstable; thus, regularization methods are needed to realize effective continuation. According to the Poisson integral plane approximate relationship between observation and continuation data, the computation formulae combined with the fast Fourier transform(FFT)algorithm are transformed to a frequency domain for accelerating the computational speed. The iterative Tikhonov regularization method and the iterative Landweber regularization method are used in this paper to overcome instability and improve the precision of the results. The availability of these two iterative regularization methods in the frequency domain is validated by simulated geomagnetic data, and the continuation results show good precision.展开更多
New acquired and reprocessed three-dimensional(3D)seismic data were used to delineate the distribution and characterization of bottom simulating reflections(BSRs)in the Chaoshan Sag,in the eastern part of Dongsha Isla...New acquired and reprocessed three-dimensional(3D)seismic data were used to delineate the distribution and characterization of bottom simulating reflections(BSRs)in the Chaoshan Sag,in the eastern part of Dongsha Island,South China Sea.Three submarine canyons with different scales were interpreted from the 3D seismic data,displaying three stages of canyon development and are related with the variation of BSR.Abundant faults were identified from the coherence and ant-tracing attributions extracted from 3D seismic data,which provide the evidence for fluid migration from deeper sediments to the gas hydrate stability zone(GHSZ).The uplift of Dongsha Island created a large number of faults and leads to the increased seafloor erosion.The erosion caused the cooling of the seafloor sediments and deepening of the base of the gas hydrate stability zone,which is attributed to the presence of paleo-BSR and BSR downward shift in the study area.Hence,methane gas may be released during the BSR resetting and gas hydrate dissociation related with seafloor erosion.展开更多
Downward Looking Sparse Linear Array Three Dimensional SAR(DLSLA 3D SAR) is an important form of 3D SAR imaging, which has a widespread application field. Since its practical equivalent phase centers are usually distr...Downward Looking Sparse Linear Array Three Dimensional SAR(DLSLA 3D SAR) is an important form of 3D SAR imaging, which has a widespread application field. Since its practical equivalent phase centers are usually distributed sparsely and nonuniformly, traditional 3D SAR algorithms suffer from low resolution and high sidelobes in cross-track dimension. To deal with this problem, this paper introduces a method based on back-projection and convex optimization to achieve 3D high accuracy imaging reconstruction. Compared with traditional SAR algorithms, the proposed method sufficiently utilizes the sparsity of the 3D SAR imaging scene and can achieve lower sidelobes and higher resolution in cross-track dimension. In the simulated experiments, the reconstructed results of both simple and complex imaging scene verify that the proposed method outperforms 3D back-projection algorithm and shows satisfying cross-track dimensional resolution and good robustness to noise.展开更多
Many observational studies have shown that deformation, like vertical vorticity and divergence, is closely related to the occurrence and distribution of strong precipitation. In this paper, to involve deformation in p...Many observational studies have shown that deformation, like vertical vorticity and divergence, is closely related to the occurrence and distribution of strong precipitation. In this paper, to involve deformation in precipitation diagnosis, a new parameter called potential deformation(PD) is derived and then applied to precipitation detection within a simulated mesoscale convective system(MCS). It is shown that PD includes both stretching deformation and shearing deformation and shares similar characteristics with deformation insofar as it does not change with the rotating coordinate. Diagnosis of the simulated MCS reveals that PD performs well in tracing the MCS' precipitation. In terms of their distributional pattern, the large-value areas of PD are similar to the precipitation in the different development stages of the MCS. A detailed analysis of the physical processes contained within the PD shows that it can reflect the three-dimensional moisture variation,vertical wind shear and wind deformation within the MCS. These structures are usually a comprehensive reflection of the characteristics of the surface cold pool, rear inflow jet, downward cold air flow and upward warm moist flow within the precipitating convective cells. For this reason, the PD shows much stronger anomalies in the precipitating atmosphere than the non-precipitating atmosphere, which implies considerable potential for its application in detecting heavy precipitation within MCSs.展开更多
The research and application of airborne gravimetry technology has become one of the hottest topics in gravity field in recent years. Downward continuation is one of the key steps in airborne gravimetry data processin...The research and application of airborne gravimetry technology has become one of the hottest topics in gravity field in recent years. Downward continuation is one of the key steps in airborne gravimetry data processing, and the quality of continuation results directly influence the further application of surveying data. The Poisson integral iteration method is proposed in this paper, and the modified Poisson integral discretization formulae are also introduced in the downward continuation of airborne gravimerty data. For the test area in this paper, compared with traditional Poisson integral discretization formula, the continuation result of modified formulae is improved by 10.8 mGal, and the precision of Poisson integral iteration method is in the same amplitude as modified formulae. So the Poisson integral iteration method can reduce the discretization error of Poisson integral formula effectively. Therefore, the research achievements in this paper can be applied directly in the data processing of our country's airborne scalar and vector gravimetry.展开更多
文摘At present,the growth momentum of the world economy is clearly insufficient,and faced with many unstable,uncertain and unpredictable factors,the world economy is generally on a downward path.From the perspective of trend changes,the world economy will still be in the process of reshaping its growth momentum in 2024,with positive factors accumulating but downward pressure remaining.
文摘This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke.
文摘Based on NCEP reanalysis data,EDAS data and ground observation data,the causes of a strong sandstorm process in Ulanqab City from March 14 to 15,2021 were analyzed.The analysis shows that"3.15"sandstorm,a sandstorm process accompanied by northwest gale behind the front,was caused by strong cold air in the north.In the early stage,the Mongolian cyclone resulted in the increase of temperature and decrease of pressure on the ground.When a strong surface cold high pressure at the rear of the cyclone invaded the city,a strong pressure gradient between high and low pressure provided dynamic conditions for the sandstorm outbreak.The transit of the surface cold front was the sign of the sandstorm outbreak,and the downward transmission of momentum at high altitudes increased the wind speed near the surface.
基金supported by Startup Funds from the Central Organization Department and the South China University of Technology(SCUT),as well as funds from the national natural science foundation of China(Grant No:U2001217)the Guangdong Science and Technology Program(2020B121201003,2019ZT08L075,2019QN01L118,2021A1515012545)the Fundamental Research Fund for the Central Universities,SCUT(2020ZYGXZR095).
文摘ABSTRACT Embedding submicrocavities is an effective approach to improve the light out-coupling efficiency(LOCE)for planar perovskite light-emitting diodes(PeLEDs).In this work,we employ phenethylammonium iodide(PEAI)to trigger the Ostwald ripening for the downward recrystallization of perovskite,resulting in spontaneous formation of buried submicrocavities as light output coupler.The simulation suggests the buried submicrocavities can improve the LOCE from 26.8 to 36.2%for near-infrared light.Therefore,PeLED yields peak external quantum efficiency(EQE)increasing from 17.3%at current density of 114 mA cm^(−2)to 25.5%at current density of 109 mA cm^(−2)and a radiance increasing from 109 to 487 W sr^(−1)m^(−2)with low rolling-off.The turn-on voltage decreased from 1.25 to 1.15 V at 0.1 W sr^(−1)m^(−2).Besides,downward recrystallization process slightly reduces the trap density from 8.90×10^(15)to 7.27×10^(15)cm^(−3).This work provides a self-assembly method to integrate buried output coupler for boosting the performance of PeLEDs.
基金supported by the National Natural Science Foundation of China(Grant Nos.42225702,42077235 and 41722209).
文摘To analyze the pipeline response under permanent ground deformation,the evolution of resistance acting on the pipe during the vertical downward offset is an essential ingredient.However,the efficient simulation of pipe penetration into soil is challenging for the conventional finite element(FE)method due to the large deformation of the surrounding soils.In this study,the B-spline material point method(MPM)is employed to investigate the pipe-soil interaction during the downward movement of rigid pipes buried in medium and dense sand.To describe the density-and stress-dependent behaviors of sand,the J2-deformation type model with state-dependent dilatancy is adopted.The effectiveness of the model is demonstrated by element tests and biaxial compression tests.Afterwards,the pipe penetration process is simulated,and the numerical outcomes are compared with the physical model tests.The effects of pipe size and burial depth are investigated with an emphasis on the mobilization of the soil resistance and the failure mechanisms.The simulation results indicate that the bearing capacity formulas given in the guidelines can provide essentially reasonable estimates for the ultimate force acting on buried pipes,and the recommended value of yield displacement may be underestimated to a certain extent.
基金supported by the National Natural Science Foundation of China (Grant Nos. 42075028 and 42222502)the Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (Grant SML2021SP302)
文摘The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams.As a result,massive surface melting events of the ice shelf are occurring more frequently,which puts the West Antarctica Ice Sheet at greater risk of degradation.This study shows the connection between surface melting and the prominent intrusion of warm and humid air flows from lower latitudes.By applying the Climate Feedback-Response Analysis Method(CFRAM),the temporal surge of the downward longwave(LW)fluxes over the surface of the Ross Ice Shelf(RIS)and adjacent regions are identified for four historically massive RIS surface melting events.The melting events are decomposed to identify which physical mechanisms are the main contributors.We found that intrusions of warm and humid airflow from lower latitudes are conducive to warm air temperature and water vapor anomalies,as well as cloud development.These changes exert a combined impact on the abnormal enhancement of the downward LW surface radiative fluxes,significantly contributing to surface warming and the resultant massive melting of ice.
基金funded by the Natural Science Foundation of China (Grant no.42171121)the open fund of Key Laboratory of Oceanic Atmospheric Chemistry and Global Change,Ministry of Natural Resources,China (Grant no.GCMAC2206)support from data availability from PROMICE and ERA5,ERA-Interim,JRA55,MERRA-2,NCEP2。
文摘Radiation is the direct energy source of the surface natural environment and the main driving force of climate change.It has increasingly become an important meteorological factor affecting the surface heat exchange and glacier mass balance,especially in the glacier changes of the Greenland Ice Sheet(Gr IS).Due to the harsh climatic conditions of Gr IS and sparse observed data,it has become an important way to obtain radiation data from reanalysis datasets.However,the applicability of these radiation data on Gr IS is uncertain and worth exploring.In this work,we evaluate five reanalysis datasets(the fifth generation of European Centre for Medium-Range Weather Forecasts(ERA5),European Centre for Medium-Range Weather Forecasts Interim Reanalysis(ERA-Interim),Japanese 55-year Reanalysis(JRA55),National Centers for Environmental Prediction Reanalysis II(NCEP2)and Modern-Era Retrospective analysis for Research and Applications,Version 2(MERRA-2))during 1997-2022 using observations from 26 Program for Monitoring the Greenland Ice Sheet(PROMICE)automatic weather stations(AWSs)and 3 K-transect AWSs on Gr IS.The conclusions are as follows:ERA5 has the best performances in downward shortwave radiation(SWD)as well as downward and upward longwave radiation(LWD and LWU),but the performance is not the best in upward shortwave radiation(SWU).Based on the radiation budget analysis with ERA5 during 1979-2022,the fluctuation of longwave radiation is greater than that of shortwave radiation.The seasonal variation of shortwave radiation is obvious,while that of longwave radiation is small.The increasing trend of longwave radiation may result from global warming,in which ice sheets absorb more solar radiation and the surface heats up significantly,emitting more LWU.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common malignant tumors in the world,which is seriously threatening the lives of patients.Due to the rapid development of the disease,patients were in the middle and advanced stages at the time of diagnosis and missed the best time for treatment.With the development of minimally invasive medicine,interventional therapy for advanced HCC has achieved promising results.Transarterial chemoembolization(TACE)and transarterial radioembolization(TARE)are currently recognized as effective treatments.This study aimed to investigate the clinical value and safety of TACE alone and combined with TACE in the treatment of progression in patients with advanced HCC and to find a breakthrough for the early diagnosis and treatment of patients with advanced HCC.AIM To investigate the efficacy and safety of hepatic TACE and TARE in advanced descending hepatectomy.METHODS In this study,218 patients with advanced HCC who were treated in the Zhejiang Provincial People’s Hospital from May 2016 to May 2021 were collected.Of the patients,119 served as the control group and received hepatic TACE,99 served as the observation group and were treated with hepatic TACE combined with TARE.The patients in two groups were compared in terms of lesion inactivation,tumor nodule size,lipiodol deposition,serum alpha-fetoprotein(AFP)level in different periods,postoperative complications,1-year survival rate,and clinical symptoms such as liver pain,fatigue,and abdominal distension,and adverse reactions such as nausea and vomiting.RESULTS The observation group and the control group had good efficacy in treatment efficiency,reduction of tumor nodules,reduction of postoperative AFP value,reduction of postoperative complications,and relief of clinical symptoms.In addition,compared with the control group,the treatment efficiency,reduction of tumor nodules,reduction of AFP value,reduction of postoperative complications,and relief of clinical symptoms in the observation group were better than those in the TACE group alone.Patients in the TACE+TARE group had a higher 1-year survival rate after surgery,lipiodol deposition was significantly increased and the extent of tumor necrosis was expanded.The overall incidence of adverse reactions in the TACE+TARE group was lower than that in the TACE group,and the difference had statistical significance(P<0.05).CONCLUSION Compared with TACE alone,TACE combined with TARE is more effective in the treatment of patients with advanced HCC.It also improves postoperative survival rate,reduces adverse effects,and has a better safety profile.
文摘The process of wafer polishing is known to be highly demanding,and even small deviations in the processing parameters can have a significant impact on the quality of the wafers obtained.During the process of wafer polishing,maintaining a constant pressure value applied by the polishing head is essential to achieve the desired flatness of the wafer.The accuracy of the downward pressure output by the polishing head is a crucial factor in producing flat wafers.In this paper,the uncertainty component of downward pressure is calculated and its measurement uncertainty is evaluated,and a method for calculating downward pressure uncertainty traceable to international basic unit is established.Therefore,the reliability of double side polishing machine has been significantly improved.
文摘Faced with the impact of complex and changeable domestic and international situations and multiple factors exceeding expectations,China's textile industry has experienced weak market demand,high raw material cost,more complex trade environment and significantly increased economic operating pressure since 2022.The growth rate of main economic indicators of the textile machinery industry continues to weaken,and the economic operation faces great downward pressure.
文摘A nine-layer spectral atmospheric general circulation model is coupled to a twenty-layer global oceanic general circulation model with the“prediction-correction”monthly anomaly exchange scheme which has been proposed at the Institute of Atmospheric Physics (IAP). A forty-year integration of the coupled model shows that the CGCM is fairly successful in keeping a reasonable pattern of the modelled SST although most of the Pacific become warmer than those given by the uncoupled ocean model. The model tends to reach a more realistic state than the uncoupled one in terms of downward surface heat flux into ocean particularly in the equatorial Pacific region. Also, the model is capable to simulate interannual variability of sea surface temperature in tropical region.
文摘The Markov process with discrete state and time is used to simulate the distribution of liquid flow in apacked column.The theoretical prediction agrees well with the experimental data.
基金funded by the Korea Meteorological Institute (Grant No. KMI 2018-05410)
文摘A precipitation system developed continuously along the western coastline of the Korean Peninsula and created considerable precipitation both along the coast and inland on 26 July 2011. In this study, the causes for this nearshore convective system are investigated from observations and the results of model experiments. Three-dimensional radar fields clearly show that a change of wind at the surface border played an important role in the development of the nearshore convection system. The simulation results, which are very similar to the observations, show that the surface border generated and maintained the convergence zone. The roughness change enhanced the convergence, and the interaction between the deepening cold pool and downward flow maintained the convergence zone. The surface mechanical discontinuity affected by the roughness change between sea and land formed the convergence (gradient of wind stress), which induced momentum transfer to the upper layer. The cold pool created a steep gradient of potential temperature and provided the reason for the propagated convergence zone with the downward flow. The maximum value of the surface change factor, which comprises the influencing factors for the long-lasting convective system, reflects the enhancement of the system at the coast.
基金supported by the National Natural Science Foundation of China(41304022,41174026,41104047)the National 973 Foundation(61322201,2013CB733303)+1 种基金the Key laboratory Foundation of Geo-space Environment and Geodesy of the Ministry of Education(13-01-08)the Youth Innovation Foundation of High Resolution Earth Observation(GFZX04060103-5-12)
文摘Downward continuation is a key step in processing airborne geomagnetic data. However,downward continuation is a typically ill-posed problem because its computation is unstable; thus, regularization methods are needed to realize effective continuation. According to the Poisson integral plane approximate relationship between observation and continuation data, the computation formulae combined with the fast Fourier transform(FFT)algorithm are transformed to a frequency domain for accelerating the computational speed. The iterative Tikhonov regularization method and the iterative Landweber regularization method are used in this paper to overcome instability and improve the precision of the results. The availability of these two iterative regularization methods in the frequency domain is validated by simulated geomagnetic data, and the continuation results show good precision.
基金the National Key R&D Program of China(No.2017YFC0307301-1)the National Natural Science Foundation of China(No.41676041)+1 种基金the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0104)the National High Technology Research and Development Program of China(863 Program)(No.2013AA092601)。
文摘New acquired and reprocessed three-dimensional(3D)seismic data were used to delineate the distribution and characterization of bottom simulating reflections(BSRs)in the Chaoshan Sag,in the eastern part of Dongsha Island,South China Sea.Three submarine canyons with different scales were interpreted from the 3D seismic data,displaying three stages of canyon development and are related with the variation of BSR.Abundant faults were identified from the coherence and ant-tracing attributions extracted from 3D seismic data,which provide the evidence for fluid migration from deeper sediments to the gas hydrate stability zone(GHSZ).The uplift of Dongsha Island created a large number of faults and leads to the increased seafloor erosion.The erosion caused the cooling of the seafloor sediments and deepening of the base of the gas hydrate stability zone,which is attributed to the presence of paleo-BSR and BSR downward shift in the study area.Hence,methane gas may be released during the BSR resetting and gas hydrate dissociation related with seafloor erosion.
基金Supported by the National Natural Science Foundation of China General Programs(Nos.61072112,61372186)the National Natural Science Foundation of China Key Program(No.60890071)
文摘Downward Looking Sparse Linear Array Three Dimensional SAR(DLSLA 3D SAR) is an important form of 3D SAR imaging, which has a widespread application field. Since its practical equivalent phase centers are usually distributed sparsely and nonuniformly, traditional 3D SAR algorithms suffer from low resolution and high sidelobes in cross-track dimension. To deal with this problem, this paper introduces a method based on back-projection and convex optimization to achieve 3D high accuracy imaging reconstruction. Compared with traditional SAR algorithms, the proposed method sufficiently utilizes the sparsity of the 3D SAR imaging scene and can achieve lower sidelobes and higher resolution in cross-track dimension. In the simulated experiments, the reconstructed results of both simple and complex imaging scene verify that the proposed method outperforms 3D back-projection algorithm and shows satisfying cross-track dimensional resolution and good robustness to noise.
基金supported by the Special Scientific Research Fund of the Meteorological Public Welfare of the Ministry of Sciences and Technology (Grant No. GYHY201406002, GYHY201406001)National Key Technology Support Program (Grant No. 2015BAC03B04)+4 种基金a National Program on Key Basic Research project (Grant No. 2013CB430105)the Major Research Plan of the National Natural Science Foundation of China (Grant No. 91437215)the National Natural Science Foundation of China (Grant Nos. 41505040, 41375052 41405055 and 41575065)the Open Project of the State Key Laboratory of Severe Weather (La SW), the Chinese Academy of Meteorological Sciences (CAMS) (Grant No. 2015LASW-B05)the Beijing Natural Sciences Foundation (Grant No. 8142035)
文摘Many observational studies have shown that deformation, like vertical vorticity and divergence, is closely related to the occurrence and distribution of strong precipitation. In this paper, to involve deformation in precipitation diagnosis, a new parameter called potential deformation(PD) is derived and then applied to precipitation detection within a simulated mesoscale convective system(MCS). It is shown that PD includes both stretching deformation and shearing deformation and shares similar characteristics with deformation insofar as it does not change with the rotating coordinate. Diagnosis of the simulated MCS reveals that PD performs well in tracing the MCS' precipitation. In terms of their distributional pattern, the large-value areas of PD are similar to the precipitation in the different development stages of the MCS. A detailed analysis of the physical processes contained within the PD shows that it can reflect the three-dimensional moisture variation,vertical wind shear and wind deformation within the MCS. These structures are usually a comprehensive reflection of the characteristics of the surface cold pool, rear inflow jet, downward cold air flow and upward warm moist flow within the precipitating convective cells. For this reason, the PD shows much stronger anomalies in the precipitating atmosphere than the non-precipitating atmosphere, which implies considerable potential for its application in detecting heavy precipitation within MCSs.
基金supported by the open foundation of State Key Laboratory of Geodesy and Earth's Dynamics(SKLGED2017-1-1-E)the National Natural Science Foundation of China(41304022, 41504018,41404020)+1 种基金the National 973 Foundation(61322201, 2013CB733303)the open foundation of Military Key Laboratory of Surveying,Mapping and Navigation of Engineering,Information Engineering University
文摘The research and application of airborne gravimetry technology has become one of the hottest topics in gravity field in recent years. Downward continuation is one of the key steps in airborne gravimetry data processing, and the quality of continuation results directly influence the further application of surveying data. The Poisson integral iteration method is proposed in this paper, and the modified Poisson integral discretization formulae are also introduced in the downward continuation of airborne gravimerty data. For the test area in this paper, compared with traditional Poisson integral discretization formula, the continuation result of modified formulae is improved by 10.8 mGal, and the precision of Poisson integral iteration method is in the same amplitude as modified formulae. So the Poisson integral iteration method can reduce the discretization error of Poisson integral formula effectively. Therefore, the research achievements in this paper can be applied directly in the data processing of our country's airborne scalar and vector gravimetry.