The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control p...The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.展开更多
Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(...Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(2))femtosecond(fs)lasers with metal flat,plastic flat,and plastic nanowire-array(NWA)targets.Detailed analyses are conducted on the EMPs in terms of their spatial distribution,time and frequency domains,radiation energy,and protection.The results indicate that EMPs from metal targets exhibit larger amplitudes at varying angles than those generated by other types of targets and are enhanced significantly for NWA targets.Using a plastic target holder and increasing the laser focal spot can significantly decrease the radiation energy of the EMPs.Moreover,the composite shielding materials indicate an effective shielding effect against EMPs.The simulation results show that the NWA targets exert a collimating effect on thermal electrons,which directly affects the distribution of EMPs.This study provides guidance for regulating EMPs by controlling the laser focal spot,target parameters,and target rod material and is beneficial for electromagnetic-shielding design.展开更多
BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasi...BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are unclear.AIM To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC.METHODS We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023.The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)frame-work.Our primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic use.RESULTS In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS matching.The urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d mortality.CONCLUSION Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay.展开更多
基金supported by the National Natural Science Foundation of China(62273213,62073199,62103241)Natural Science Foundation of Shandong Province for Innovation and Development Joint Funds(ZR2022LZH001)+4 种基金Natural Science Foundation of Shandong Province(ZR2020MF095,ZR2021QF107)Taishan Scholarship Construction Engineeringthe Original Exploratory Program Project of National Natural Science Foundation of China(62250056)Major Basic Research of Natural Science Foundation of Shandong Province(ZR2021ZD14)High-level Talent Team Project of Qingdao West Coast New Area(RCTD-JC-2019-05)。
文摘The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.
基金This work was supported by the National Natural Science Foundation of China(Nos.12122501,11975037,61631001,and 11921006)the National Grand Instrument Project(Nos.2019YFF01014400,2019YFF01014404)the Foundation of Science and Technology on Plasma Physics Laboratory(No.6142A04220108).
文摘Ultrashort and powerful laser interactions with a target generate intense wideband electromagnetic pulses(EMPs).In this study,we report EMPs generated by the interactions between petawatt(30 fs,1.4×10^(20) W/cm^(2))femtosecond(fs)lasers with metal flat,plastic flat,and plastic nanowire-array(NWA)targets.Detailed analyses are conducted on the EMPs in terms of their spatial distribution,time and frequency domains,radiation energy,and protection.The results indicate that EMPs from metal targets exhibit larger amplitudes at varying angles than those generated by other types of targets and are enhanced significantly for NWA targets.Using a plastic target holder and increasing the laser focal spot can significantly decrease the radiation energy of the EMPs.Moreover,the composite shielding materials indicate an effective shielding effect against EMPs.The simulation results show that the NWA targets exert a collimating effect on thermal electrons,which directly affects the distribution of EMPs.This study provides guidance for regulating EMPs by controlling the laser focal spot,target parameters,and target rod material and is beneficial for electromagnetic-shielding design.
基金The study was approved by the Ethics Committee(2019ZDSYLL094-P01).
文摘BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are unclear.AIM To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC.METHODS We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023.The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)frame-work.Our primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic use.RESULTS In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS matching.The urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d mortality.CONCLUSION Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay.
