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The Stability of Banach Frames in Banach Spaces

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Acta Mathematica sinica,English Series 2010年第12期26卷 2369-2376页

作者： Yu Can ZHU si yuan wang Department of Mathematics Fuzhou University Fuzhou 350108 P. R. China Department of Mathematics Shangrao Normal School Shangrao 334000 P. R. China

In this paper, we give some equivalent conditions on a Banach frame for a Banach space by using the pseudoinverse operator. We also consider the stability of a Banach frame for a Banach space X with respect to Xd or an Xd-frame for a Banach space X under perturbation. These results generalize and improve the related works of Balan, Casazza, Christensen, Stoeva and Jian et al.

关键词： Frame Banach frame Xd-frame pseudoinverse operator

Task assignment in ground-to-air confrontation based on multiagent deep reinforcement learning

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Defence Technology（防务技术） 2023年第1期19卷 210-219页

作者： Jia-yi Liu Gang wang Qiang Fu Shao-hua Yue si-yuan wang Air and Missile Defense College Air Force Engineering UniversityXi'an710051China Air Force Engineering University Changle East RoadXi'anShaanxi710051China

The scale of ground-to-air confrontation task assignments is large and needs to deal with many concurrent task assignments and random *** at the problems where existing task assignment methods are applied to ground-to-air confrontation,there is low efficiency in dealing with complex tasks,and there are interactive conflicts in multiagent *** study proposes a multiagent architecture based on a one-general agent with multiple narrow agents(OGMN)to reduce task assignment *** the slow speed of traditional dynamic task assignment algorithms,this paper proposes the proximal policy optimization for task assignment of general and narrow agents(PPOTAGNA)*** algorithm based on the idea of the optimal assignment strategy algorithm and combined with the training framework of deep reinforcement learning(DRL)adds a multihead attention mechanism and a stage reward mechanism to the bilateral band clipping PPO algorithm to solve the problem of low training ***,simulation experiments are carried out in the digital *** multiagent architecture based on OGMN combined with the PPO-TAGNA algorithm can obtain higher rewards faster and has a higher win *** analyzing agent behavior,the efficiency,superiority and rationality of resource utilization of this method are verified.

关键词： Ground-to-air confrontation Task assignment General and narrow agents Deep reinforcement learning Proximal policy optimization(PPO)

Over-sampling basis expansion model aided channel estimation for OFDM systems with ICI

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 7-13页

作者： LIU si-yang LIU yuan-an wang Fei-fei XIE Gang ZHANG Ran-ran Key Laboratory of Universal Wireless Communications (Beijing University of Posts and Telecommunications) Ministry of Education Beijing 100876 China

The rapid variation of channel can induce the intercarrier interference in orthogonal frequency-division multiplexing （OFDM） systems. Intercarrier interference will significantly increase the difficulty of OFDM channel estimation because too many channel coefficients need be estimated. In this article, a novel channel estimator is proposed to resolve the above problem. This estimator consists of two parts： the channel parameter estimation unit （CPEU）, which is used to estimate the number of channel taps and the multipath time delays, and the channel coefficient estimation unit （CCEU）, which is used to estimate the channel coefficients by using the estimated channel parameters provided by CPEU. In CCEU, the over-sampling basis expansion model is resorted to solve the problem that a large number of channel coefficients need to be estimated. Finally, simulation results are given to scale the performance of the proposed scheme.

关键词： OFDM ICI over-sampling basis expansion model (OBEM)

Sclerosing cholangitis secondary to bleomycin-iodinated embolization for liver hemangioma

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World Journal of Gastroenterology 2014年第46期20卷 17680-17685页

作者： Shuo Jin Xiao-Ju Shi Xiao-Dong Sun si-yuan wang Guang-Yi wang Department of Hepatobiliary and Pancreatic Surgery the First Norman Bethune Hospital Affiliated to Jilin University Department of Surgery Intensive Care Unit Beijing Chao-yang Hospital Affiliated to Capital Medical University

Sclerosing cholangitis(SC)is a rarely reported morbidity secondary to transcatheter arterial chemoembolization(TACE)with bleomycin-iodinated oil(BIO)for liver cavernous hemangioma(LCH).This report retrospectively evaluated the diagnostic and therapeutic course of a patient with LDH who presented obstructive jaundice 6 years after TACE with *** imaging identified a suspected malignant biliary stricture located at the convergence of the left and right hepatic *** exploration demonstrated a full-thickness sclerosis of the hilar bile duct with right hepatic duct stricture and right lobe *** hepatic hilar resection with right-side hemihepatectomy and Roux-en-Y hepaticojejunostomy was performed because hilar cancer could not be excluded on frozen *** results showed chronic pyogenic inflammation of the common and right hepatic ducts with SC in the portal *** SC is a long-term complication that may occur in LCH patients after TACE with BIO and must be differentiated from hilar *** duct plasty is a definitive but technically challenging treatment modality for secondary SC.

关键词： Sclerosing cholangitis Secondary Transcatheter arterial chemoembolization Bleomycin-iodinated oil Liver cavernous hemangioma Hilar stricture Differential diagnosis Definitive surgery

Drainage fluid and serum amylase levels accurately predict development of postoperative pancreatic fistula

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World Journal of Gastroenterology 2017年第34期23卷 6357-6364页

作者： Shuo Jin Xiao-Ju Shi si-yuan wang Ping Zhang Guo-Yue Lv Xiao-Hong Du Guang-Yi wang School of Clinical Medicine Tsinghua University Department of Hepatobiliary and Pancreatic Surgery Beijing Tsinghua Changgung Hospital Medical CenterTsinghua University Department of Hepatobiliary and Pancreatic Surgery Bethune First Hospital of Jilin University Department of Respiratory and Critical Care Medicine Beijing Chao-yang Hospital Affiliated to Capital Medical University

AIM To investigate potential biomarkers for predicting postoperative pancreatic fistula( POPF) after pancreaticoduodenectomy(PD).METHODS We prospectively recruited 83 patients to this study. All patients underwent PD(Child's procedure) at the Division of Hepatobiliary and Pancreas Surgery at the First Bethune Hospital of Jilin University between June 2011 and April 2015. Data pertaining to demographic variables, clinical characteristics, texture of pancreas, surgical approach, histopathological results, white blood cell count, amylase and choline levels in the serum, pancreatic/gastric drainage fluid, and choline and amylase levels in abdominal drainage fluid were included in the analysis. Potential correlations between these parameters and postoperative complications such as, POPF, acute pancreatitis, hemorrhage, delayed gastric emptying, and biliary fistula, were assessed. RESULTS Twenty-eight out of the 83(33.7%) patients developed POPF. The severity of POPF was classified as Grade A in 8(28%) patients, grade B in 16(58%), and grade C in4(14%), according to the pancreatic fistula criteria. On univariate and multivariate logistic regression analyses, higher amylase level in the abdominal drainage fluid on postoperative day(POD)1 and higher serum amylase levels on POD4 showed a significant correlation with POPF(P sis, amylase cut-off level of 2365.5 U/L in the abdominal drainage fluid was associated with a 78.6% sensitivity and 80% specificity [area under the curve(AUC): 0.844; P = 0.009]. A cut-off serum amylase level of 44.2 U/L was associated with a 78.6% sensitivity and 70.9% specificity(AUC: 0.784; P = 0.05).CONCLUsiON Amylase level in the abdominal drainage fluid on POD1 and serum amylase level on POD4 represent novel biomarkers associated with POPF development.

关键词： Pancreaticoduodenectomy Complication Amylase Pancreatic fistula

Oxidative heat release intensity in coal at low temperatures measured by the hot-wire method

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Mining Science and Technology 2009年第3期19卷 326-330页

作者： YANG Yong-liang LI Zeng-hua PAN Shang-kun GAO si-yuan wang Ya-li School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Directly measuring the oxidative heat release intensity at low temperatures is difficult at *** developed a new method based on heat conduction theory that directly measures heat release intensity of loose coal at low *** this method, we calculated the oxidative heat release intensity of differently sized loose coals by comparing the temperature rise of the coal in nitrogen or an air *** results show that oxidation heat release intensity of Shenhua coal sized 0～15 mm is 0.001～0.03 W/m3 at 30～90 °C and increases with increasing *** heat release intensity at a given temperature is larger for smaller sized *** temperature effect on heat release intensity is muted as the coal size *** lower temperature the change in heat release intensity as a function of size becomes *** results show that the test system is usable for practical applications and is easy to operate and is capable of measuring mass samples.

关键词： coal spontaneous combustion oxidation heat release intensity of coal test system diameter

Focal mechanism caused by fracture or burst of a coal pillar

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Journal of China University of Mining and Technology 2008年第2期18卷 153-158页

作者： CAO An-ye DOU Lin-ming CHEN Guo-xiang GONG si-yuan wang Yu-gang LI Zhi-hua State Key Laboratory of Coal Resource and Mine Safety China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

As a regional, real-time and dynamic method, microseismic monitoring technology is quite an appropriate technology for forecasting geological hazards, such as rock bursts, mine tremors, coal and gas outbursts and can even be used to prevent or at least reduce these disasters. The study of the focal mechanisms of different seismic sources is the prerequisite and basis for forecasting rock burst by microseismic monitoring technology. Based on the analysis on the mechanism and fracture course of coal pillars where rock bursts occur mostly, the equivalent point source model of the seismicity caused by a coal pillar was created. Given the model, the seismic displacement equation of a coal pillar was analyzed and the seismic mechanism was pointed out by seismic wave theory. The course of the fracture of the coal pillar was simulated closely in the laboratory and the equivalent microseismic signals of the fractures of the coal pillar were acquired using a TDS-6 experimental system. The results show that, by the pressure and friction of a medium near the seismic source, both a compression wave and a shear wave will be emitted and shear fracture will be induced at the moment of breakage. The results can be used to provide an academic basis to forecast and prevent rock bursts or tremors in a coal pillar.

关键词： coal pillar rock burst microseismicity fracture focal mechanism point source model

Large angle radiation effect on jet measurement in pp collisions at s^(1/2)=7 TeV at the LHC

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Chinese Physics C 2018年第11期42卷 58-62页

作者： Ren-Zhuo Wan si-yuan wang Shuang Li Yi-Ming Feng Feng Liu Fan Yang Dai-Cui Zhou Nano-Optical Material and Storage Device Research Center School of Electronic and Electrical Engineering Wuhan Textile UniversityWuhan 430200China Key Laboratory of Quark and Lepton Physics（MOE）and Institute of Particle Physics Central China Normal UniversityWuhan 430079China College of Science China Three Gorges UniversityYichang 443002China

Jet measurement is an ideal probe to explore the properties of the hot dense matter created in ultra- relativistic heavy-ion collisions. Recent results at the LHC show that large angle radiation is non-negligible, but the mechanisms and phenomenology of large angle radiation are still unclear and hotly debated. Considering the coexistence and competition of different physics mechanisms qualitatively, it is assumed that the radiation angle is enhanced randomly over a wide range based on the collinear approximation. Its effects on di-jet momentum imbalance, jet fragmentation function and jet shape are studied in pp collisions at 7 TeV. The results show that di-jet asymmetry is insensitive to large angle radiation, while jet shape and jet fragmentation functions are more sensitive and could explain experimental data well. We conclude that de-collimated radiation cannot be ignored for soft jets, and there is a contribution from large angle radiation （Ф 〉 0.7） of about 8%, which is significant for jet intrinsic structure measurement at PT,jeT 〈80 GeV/c.

关键词： quark gluon plasma jet quenching di-jet large angle radiation jet shape

Continuing Care for Older Patients During the Transitional Period

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Chinese Nursing Research 2014年第1期1卷 1-13页

作者： si-yuan wang Yue Zhao Xiao-Ying Zang School of Nursing Tianjin Medical University

Background： The world is facing increasing pressure with the continuous growth of the older population. Older patients are usually discharged with complex medical problems, high stress and vulnerability, and these factors place the elderly at risk for poor outcomes. Purpose： The present review summarizes a method for providing appropriate and affordable health services by nursing professionals to meet older patient＇s health care needs during their transitional period which is defined as a period from discharge after hospitalization for a major disorder to recovery in a home setting. Summary： Older patients with chronic diseases need seamless health care during a transitional period-a highly stressful and vulnerable period for them. Nurse professionals can conduct decent discharge planning to assist older patients with transitional problems through continuous healthcare. This review summarized the need of continuing care for older patients during the transitional period, the definition of discharge planning, the conceptual framework of discharge planning, and the professionals involved in discharge planning. It also highlighted the problems of discharge planning and follow-up intervention implementation in the mainland of China. Clinical implications： Inadequate discharge planning and follow-up were leading factors associ- ated with the readmission of discharged older patients. Further nursing-led discharge planning should be reinforced in China.

关键词： Older patients Continuing care Transitional care Multidisciplinary Nurse-led Adherence