Exchanges and mutual learning between the Chinese and foreign civilizations are an important part of human cultural development.The Chinese civilization adopts an all-embracing,open and inclusive attitude to understan...Exchanges and mutual learning between the Chinese and foreign civilizations are an important part of human cultural development.The Chinese civilization adopts an all-embracing,open and inclusive attitude to understand the different views of different civilizations on the connotation of values.The ancient Silk Road has opened a new window of friendship between countries and written a new chapter in the development of mankind.展开更多
研究多站点传送带给料生产加工站(Conveyor-serviced production station,CSPS)系统的最优控制问题,其优化目标是通过合理选择每个CSPS的Look-ahead控制策略,实现整个系统的工件处理率最大.本文首先根据多Agent系统的反应扩散思想,对每...研究多站点传送带给料生产加工站(Conveyor-serviced production station,CSPS)系统的最优控制问题,其优化目标是通过合理选择每个CSPS的Look-ahead控制策略,实现整个系统的工件处理率最大.本文首先根据多Agent系统的反应扩散思想,对每个Agent的原始性能函数进行改进,引入了具有扩散功能的局域信息交互项(原始项看作具有反应功能);并运用性能势理论,构建一种适用于平均和折扣两种性能准则的Wolf-PHC多Agent学习算法,以求解决策时刻不同步的多站点的协作Look-ahead控制策略.最后,论文通过仿真实验验证了该算法的有效性,学习结果表明,通过性能函数的改进,各工作站的负载平衡性得到改善,整个系统的工件处理率也明显提高.展开更多
In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be...In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be indeterminate under an active forwardlooking rule than under the corresponding backward-looking rule. It is also shown that backward-looking roles can render the monetary steady state unstable.展开更多
针对基于You Only Look Once v2算法的目标检测存在精度低及稳健性差的问题,提出一种车辆目标实时检测的You Only Look Once v2优化算法;该算法以You Only Look Once v2算法为基础,通过增加网络深度,增强特征提取能力,同时,通过添加残...针对基于You Only Look Once v2算法的目标检测存在精度低及稳健性差的问题,提出一种车辆目标实时检测的You Only Look Once v2优化算法;该算法以You Only Look Once v2算法为基础,通过增加网络深度,增强特征提取能力,同时,通过添加残差模块,解决网络深度增加带来的梯度消失或弥散问题;该方法将网络结构中低层特征与高层特征进行融合,提升对小目标车辆的检测精度。结果表明,通过在KITTI数据集上进行测试,优化后的算法在检测速度不变的情况下,提高了车辆目标检测精度,平均精度达到0.94,同时提升了小目标检测的准确性。展开更多
AIM: The clinical value of second-look endoscopy(SLE) after endoscopic submucosal dissection(ESD) has been doubted continuously. The aim of this study was to assess the effectiveness of SLE based on the risk of delaye...AIM: The clinical value of second-look endoscopy(SLE) after endoscopic submucosal dissection(ESD) has been doubted continuously. The aim of this study was to assess the effectiveness of SLE based on the risk of delayed bleeding after ESD. METHODS: A total of 310 lesions of gastric epithelial neoplasms treated by ESD were reviewed. The lesions were divided into two groups based on the risk of postprocedural bleeding estimated by Forrest classification. The high risk of rebleeding group(Forrest?Ⅰa,?Ⅰb and Ⅱa) required endoscopic treatment, while the low risk of rebleeding group(Forrest Ⅱb, Ⅱc and Ⅲ) did not. Delayed bleeding after ESD was investigated. RESULTS: Sixty-six lesions were included in the high risk of rebleeding group and 244 lesions in the low risk of rebleeding group. There were no significant differences in delayed bleeding between the high risk group(1/66) and the low risk group(1/244)(P = 0.38). The high risk of rebleeding group tended to be located more often in the mid-third and had higher appearance of flat or depressed shape than the low risk group(P = 0.004 and P = 0.006, respectively). CONCLUSION: SLE with pre-emptive prophylactic endoscopic treatment is still effective in preventing delayed bleeding after ESD.展开更多
Generally complex 3D contours are divided into a lot of continuous small line blocks by CAD/CAM software. When these small line blocks are used in conventional way,machine tool has to stop at the end of one move befor...Generally complex 3D contours are divided into a lot of continuous small line blocks by CAD/CAM software. When these small line blocks are used in conventional way,machine tool has to stop at the end of one move before continuing on to the next to meet accuracy requirement,which results in inefficiency.Look-ahead is an intelligent function that aims at adjusting the feed rate automatically to achieve maximum productivity while maintaining accuracy.By now most researchers just utilize the simplest linear acceleration(ACC)and deceleration(DEC)to deal with look-ahead intelligence.A generalized ACC/DEC ap- proach and corresponding optimal look-ahead algorithm based on dynamic back tracking along a doubly linked list are proposed.An improved rounding strategy for reducing interpolation errors is also presented.By using the proposed techniques,arbitrary velocity profiles that offer look-ahead feature and have the desired ACC/DEC characteristics for movement of a lot of continuous line blocks can be generated efficiently.Both simulations and experiments showed the productivity was dramatically increased without sacri- fice of accuracy.展开更多
The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table （LUT）, which is usually created for a special remote sensor and cannot be applied to other sensors. For practica...The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table （LUT）, which is usually created for a special remote sensor and cannot be applied to other sensors. For practical application, a general purpose Rayleigh scattering LUT which can be applied to all ocean color remote sensors is generated. An adding-doubling method to solve the vector radiative transfer equation in the plane-parallel atmosphere is deduced in detail. Compared with the exact Rayleigh scattering radiance derived from the MODIS exact Rayleigh scattering LUT, it is proved that the relative error of Rayleigh scattering calculation with the adding-doubling method is less than 0.25%, which meets the required accuracy of the atmospheric correction of ocean color remote sensing. Therefore, the adding-doubling method can be used to generate the exact Rayleigh scattering LUT for the ocean color remote sensors. Finally, the general purpose exact Rayleigh scattering LUT is generated using the adding-doubling method. On the basis of the general purpose LUT, the calculated Rayleigh scattering radiance is tested by comparing with the LUTs ofMODIS, SeaWiFS and the other ocean color sensors, showing that the relative errors are all less than 0.5%, and this general purpose LUT can be applied to all ocean color remote sensors.展开更多
BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with...BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with the increasing prevalence of cardiovascular and cerebrovascular diseases in an aging population with associated lifestyle-related diseases, an increasing number of patients receive antithrombotics. Several attempts have been made to prevent PDB in aging population;however, a consensus has yet to be reached.AIM To examine the efficacy of third-look endoscopy(TLE) for PDB prevention.METHODS One hundred patients with early gastric neoplasms receiving antithrombotics were prospectively enrolled and subjected to ESD with TLE between February 2017 and July 2019. The primary endpoint was PDB rate, which was compared with our preset threshold. Furthermore, we divided the bleeding period into early-and late-onset PDB(E-PDB and L-PDB, respectively) and analyzed its rate. As a secondary analysis, we compared PDB rates with those of a historical control group, using propensity score matching, and calculated the PDB rates per antithrombotic agent use in each group.RESULTS In total, 96 patients and 114 specimens were finally evaluated. The overall PDB rate was 7.9%(9/114) [90%CI: 4.7-13.1, P = 0.005], while the late-and early-onset PDB rates(L-PDB and E-PDB) were 5.3% [90%CI: 2.7-9.9, P < 0.0001] and 2.6% [90%CI: 1.1-6.4, P = 0.51], respectively. Propensity score matching generated 58 matched pairs for TLE and control groups. No differences were found in overall PDB incidence(10.3% vs 20.7%, P = 0.12), whereas L-PDB occurrence significantly differed(5.2% vs 17.2%, P = 0.04) between groups. Considering antithrombotics' use, the overall PDB rate was higher for direct oral anticoagulants and multiple antithrombotics in the control group, while L-PDB incidence was lower in the TLE group for these agents(8.7% vs 23.1% and 5.0% vs 29.4%, respectively).CONCLUSION TLE for gastric ESD reduces overall PDB, and especially L-PDB incidence, among patients receiving antithrombotics.展开更多
文摘Exchanges and mutual learning between the Chinese and foreign civilizations are an important part of human cultural development.The Chinese civilization adopts an all-embracing,open and inclusive attitude to understand the different views of different civilizations on the connotation of values.The ancient Silk Road has opened a new window of friendship between countries and written a new chapter in the development of mankind.
文摘研究多站点传送带给料生产加工站(Conveyor-serviced production station,CSPS)系统的最优控制问题,其优化目标是通过合理选择每个CSPS的Look-ahead控制策略,实现整个系统的工件处理率最大.本文首先根据多Agent系统的反应扩散思想,对每个Agent的原始性能函数进行改进,引入了具有扩散功能的局域信息交互项(原始项看作具有反应功能);并运用性能势理论,构建一种适用于平均和折扣两种性能准则的Wolf-PHC多Agent学习算法,以求解决策时刻不同步的多站点的协作Look-ahead控制策略.最后,论文通过仿真实验验证了该算法的有效性,学习结果表明,通过性能函数的改进,各工作站的负载平衡性得到改善,整个系统的工件处理率也明显提高.
基金Project supported by National Natural Science Foundation of China （Grant No. 70071012）
文摘In the framework of an overlapping generations model, forward-looking monetary policy roles and backward-looking monetary policy rules were investigated. It is shown that the monetary steady state is more likely to be indeterminate under an active forwardlooking rule than under the corresponding backward-looking rule. It is also shown that backward-looking roles can render the monetary steady state unstable.
文摘针对基于You Only Look Once v2算法的目标检测存在精度低及稳健性差的问题,提出一种车辆目标实时检测的You Only Look Once v2优化算法;该算法以You Only Look Once v2算法为基础,通过增加网络深度,增强特征提取能力,同时,通过添加残差模块,解决网络深度增加带来的梯度消失或弥散问题;该方法将网络结构中低层特征与高层特征进行融合,提升对小目标车辆的检测精度。结果表明,通过在KITTI数据集上进行测试,优化后的算法在检测速度不变的情况下,提高了车辆目标检测精度,平均精度达到0.94,同时提升了小目标检测的准确性。
文摘AIM: The clinical value of second-look endoscopy(SLE) after endoscopic submucosal dissection(ESD) has been doubted continuously. The aim of this study was to assess the effectiveness of SLE based on the risk of delayed bleeding after ESD. METHODS: A total of 310 lesions of gastric epithelial neoplasms treated by ESD were reviewed. The lesions were divided into two groups based on the risk of postprocedural bleeding estimated by Forrest classification. The high risk of rebleeding group(Forrest?Ⅰa,?Ⅰb and Ⅱa) required endoscopic treatment, while the low risk of rebleeding group(Forrest Ⅱb, Ⅱc and Ⅲ) did not. Delayed bleeding after ESD was investigated. RESULTS: Sixty-six lesions were included in the high risk of rebleeding group and 244 lesions in the low risk of rebleeding group. There were no significant differences in delayed bleeding between the high risk group(1/66) and the low risk group(1/244)(P = 0.38). The high risk of rebleeding group tended to be located more often in the mid-third and had higher appearance of flat or depressed shape than the low risk group(P = 0.004 and P = 0.006, respectively). CONCLUSION: SLE with pre-emptive prophylactic endoscopic treatment is still effective in preventing delayed bleeding after ESD.
文摘Generally complex 3D contours are divided into a lot of continuous small line blocks by CAD/CAM software. When these small line blocks are used in conventional way,machine tool has to stop at the end of one move before continuing on to the next to meet accuracy requirement,which results in inefficiency.Look-ahead is an intelligent function that aims at adjusting the feed rate automatically to achieve maximum productivity while maintaining accuracy.By now most researchers just utilize the simplest linear acceleration(ACC)and deceleration(DEC)to deal with look-ahead intelligence.A generalized ACC/DEC ap- proach and corresponding optimal look-ahead algorithm based on dynamic back tracking along a doubly linked list are proposed.An improved rounding strategy for reducing interpolation errors is also presented.By using the proposed techniques,arbitrary velocity profiles that offer look-ahead feature and have the desired ACC/DEC characteristics for movement of a lot of continuous line blocks can be generated efficiently.Both simulations and experiments showed the productivity was dramatically increased without sacri- fice of accuracy.
基金supported by the National Natural Science Foundation of China under contract No.40506036the High Tech Research and Development"863"Program of China under contract No.2003AA131160-04the Science and Technology Plan of Zhejiang Province of China under contract Nos 2004E60054 and 2004C13027.
文摘The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table （LUT）, which is usually created for a special remote sensor and cannot be applied to other sensors. For practical application, a general purpose Rayleigh scattering LUT which can be applied to all ocean color remote sensors is generated. An adding-doubling method to solve the vector radiative transfer equation in the plane-parallel atmosphere is deduced in detail. Compared with the exact Rayleigh scattering radiance derived from the MODIS exact Rayleigh scattering LUT, it is proved that the relative error of Rayleigh scattering calculation with the adding-doubling method is less than 0.25%, which meets the required accuracy of the atmospheric correction of ocean color remote sensing. Therefore, the adding-doubling method can be used to generate the exact Rayleigh scattering LUT for the ocean color remote sensors. Finally, the general purpose exact Rayleigh scattering LUT is generated using the adding-doubling method. On the basis of the general purpose LUT, the calculated Rayleigh scattering radiance is tested by comparing with the LUTs ofMODIS, SeaWiFS and the other ocean color sensors, showing that the relative errors are all less than 0.5%, and this general purpose LUT can be applied to all ocean color remote sensors.
文摘BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with the increasing prevalence of cardiovascular and cerebrovascular diseases in an aging population with associated lifestyle-related diseases, an increasing number of patients receive antithrombotics. Several attempts have been made to prevent PDB in aging population;however, a consensus has yet to be reached.AIM To examine the efficacy of third-look endoscopy(TLE) for PDB prevention.METHODS One hundred patients with early gastric neoplasms receiving antithrombotics were prospectively enrolled and subjected to ESD with TLE between February 2017 and July 2019. The primary endpoint was PDB rate, which was compared with our preset threshold. Furthermore, we divided the bleeding period into early-and late-onset PDB(E-PDB and L-PDB, respectively) and analyzed its rate. As a secondary analysis, we compared PDB rates with those of a historical control group, using propensity score matching, and calculated the PDB rates per antithrombotic agent use in each group.RESULTS In total, 96 patients and 114 specimens were finally evaluated. The overall PDB rate was 7.9%(9/114) [90%CI: 4.7-13.1, P = 0.005], while the late-and early-onset PDB rates(L-PDB and E-PDB) were 5.3% [90%CI: 2.7-9.9, P < 0.0001] and 2.6% [90%CI: 1.1-6.4, P = 0.51], respectively. Propensity score matching generated 58 matched pairs for TLE and control groups. No differences were found in overall PDB incidence(10.3% vs 20.7%, P = 0.12), whereas L-PDB occurrence significantly differed(5.2% vs 17.2%, P = 0.04) between groups. Considering antithrombotics' use, the overall PDB rate was higher for direct oral anticoagulants and multiple antithrombotics in the control group, while L-PDB incidence was lower in the TLE group for these agents(8.7% vs 23.1% and 5.0% vs 29.4%, respectively).CONCLUSION TLE for gastric ESD reduces overall PDB, and especially L-PDB incidence, among patients receiving antithrombotics.
