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China Communications 2024年第4期21卷 88-103页

作者： ke Hongchang Wang hui sun Hongbin Halvin Yang School of Computer Technology and Engineering Changchun Institute of TechnologyChangchun 130012China College of Computer Science and Engineering Changchun University of TechnologyChangchun 130012China Department of Electronic and Electrical Engineering University College LondonLondonUK

Emerging mobile edge computing(MEC)is considered a feasible solution for offloading the computation-intensive request tasks generated from mobile wireless equipment(MWE)with limited computational resources and *** to the homogeneity of request tasks from one MWE during a longterm time period,it is vital to predeploy the particular service cachings required by the request tasks at the MEC *** this paper,we model a service caching-assisted MEC framework that takes into account the constraint on the number of service cachings hosted by each edge server and the migration of request tasks from the current edge server to another edge server with service caching required by ***,we propose a multiagent deep reinforcement learning-based computation offloading and task migrating decision-making scheme(MBOMS)to minimize the long-term average weighted *** proposed MBOMS can learn the near-optimal offloading and migrating decision-making policy by centralized training and decentralized *** and comprehensive simulation results reveal that our proposed MBOMS can converge well after training and outperforms the other five baseline algorithms.

关键词： deep reinforcement learning mobile edge computing service caching service migrating

High quality-performance by changing parameters of antenna array

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Journal of Central South University 2022年第1期29卷 146-156页

作者： XU Xue-mei WEN Jun CHENG Wei sun ke-hui DING Yi-peng JIANG Zhao-hui School of Physics and Electronics Central South UniversityChangsha 410083China School of Automation Central South UniversityChangsha 410083China

Several antennas based on cylindrical array and uniform hexagonal array are designed and fabricated on flexible *** validate the designed prototypes,the antennas are fabricated and their performance is *** highlight scheme is to improve the signal performance and electromagnetic field distribution by appropriately changing the parameters of the antennas array,signal frequencies,and steering *** proposed antennas array is capable of applying shaping radiation band technique to generate tunable power and radiation *** distribution of the field,and the bit-error-rate transmigration coefficient characteristics are *** results show that the proposed scheme can achieve better performance by searching the optimal parameters of antenna array.

关键词： array antenna structure bit-error-rate electromagnetic beam antenna parameters high speed frequencies

本科生导师制助推拔尖创新人才培养的探索与实践——以中南大学物理学院为例

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教育教学论坛 2024年第1期 1-4页

作者：欧阳方平孙克辉孟建桥中南大学物理学院湖南长沙410012

导师制在世界高等教育发展与高校人才培养模式及博雅教育理念施行中扮演着非常重要的角色。本科生导师制在以“一制四化”为重点的拔尖创新人才培养模式改革与综合环境构筑中发挥了巨大作用。针对当前导师制实施过程中存在的问题和高校... 详细信息

导师制在世界高等教育发展与高校人才培养模式及博雅教育理念施行中扮演着非常重要的角色。本科生导师制在以“一制四化”为重点的拔尖创新人才培养模式改革与综合环境构筑中发挥了巨大作用。针对当前导师制实施过程中存在的问题和高校传统教学模式对拔尖创新人才培养的不尽如人意,探讨了本科生导师制结合思政教育贯穿、创新创业能力提升、学赛相长、科教融合及本-硕协同育人来助推拔尖创新人才培养,为拔尖创新人才培养模式的理性回归与培养质量的全面提升提供参考。

关键词：本科生导师制人才培养拔尖创新科教融合探索与实践

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese Journal of Natural Medicines 2024年第2期22卷 161-170页

作者： sun Zeshi LIN Shan WU Zhi-Li DONG Hong-Yuan XU Xi-ke LI hui-Liang WANG Jinxin School of Pharmacy Second Military Medical UniversityShanghai 200433China State key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Our continued works on the chemical constituents of Ginkgo biloba(***)leaves has led to the isolation of two novel phenylbutenoids(1,2),along with five previously unidentified terpene glycosides(3−7).Among them,compounds 1 and 2 represent unique(Z)-phenylbutenoids,3−6 are megastigmane glycosides,and 7 is identified as a rare bilobanone glycoside(Fig.1).This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from *** chemical structures of these compounds were elucidated through extensive spectroscopic analysis,including HR-ESI-MS and various 1D and 2D NMR ***,the absolute configurations of these molecules were determined using Mosher’s method,ECD experiments,and Cu-KαX-ray crystallographic analyses.

关键词： Ginkgo biloba Phenylbutenoid Megastigmane glycoside Bilobanone glycoside

NiO-Doped Fe_(2)O_(3)/MgO Properties for the Chemical Looping Oxidative Dehydrogenation of Ethane

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 27-33页

作者： Liang Hao Chen Junjie sun Jie sun hui Shenyang Ligong University Shenyang 110159China Fushun Ecology Environment Bureau Qingyuan County Branch Fushun 113399China

Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for ethylene ***_(2)O_(3)/MgO oxygen carrier was prepared using the co-precipitation *** influence of added NiO and its different loadings on Fe_(2)O_(3)/MgO were ***,a series of oxygen carriers were applied in the CL-ODH of the ethane cycle ***-Emmett-Teller(BET),X-ray diffractometry(XRD),X-ray photoelection spectroscopy(XPS),and H2-temperature programmed reduction(TPR)were used to characterize the physicochemical properties of these oxygen *** was confirmed that an interaction between NiO and Fe_(2)O_(3) occurred based on the XPS and H2-TPR *** on the CL-ODH activity performance tests conducted in a fixed-bed reactor,it was revealed that ethylene selectivity was significantly improved after NiO ***_(2)O_(3)-10%NiO/MgO showed the best activity performance with 93%ethane conversion and 50%ethylene selectivity at a reaction temperature of 650℃,atmospheric pressure,and space velocity of 7500 mL/(g·h).

关键词： chemical looping oxidative dehydrogenation oxygen carrier Fe_(2)O_(3)/MgO NiO

Pylorus-preserving gastrectomy for early gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 653-658页

作者： ke-Kang sun Yong-You Wu Department of Gastrointestinal Surgery The Affiliated Kunshan Hospital to Jiangsu UniversitySuzhou 215300Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215008Jiangsu ProvinceChina

Pylorus-preserving gastrectomy(PPG)has been widely accepted as a function-preserving gastrectomy for middle-third early gastric cancer(EGC)with a distal tumor border at least 4 cm proximal to the *** procedure essentially preserves the function of the pyloric sphincter,which requires to preserve the upper third of the stomach and a pyloric cuff at least 2.5 *** suprapyloric and infrapyloric vessels are usually preserved,as are the hepatic and pyloric branches of the vagus *** with distal gastrectomy,PPG has significant advantages in preventing dumping syndrome,body weight loss and bile reflux *** postoperative complications after PPG have reached an acceptable *** can be considered a safe,effective,and superior choice in EGC,and is expected to be extensively performed in the future.

关键词： Gastric cancer Pylorus-preserving gastrectomy Oncological safety Gastric stasis

分数阶混沌系统的Adomian分解法求解及其复杂性分析

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物理学报 2014年第3期63卷 50-57页

作者：贺少波孙克辉王会海中南大学物理与电子学院长沙410083

根据分数阶微分定义,采用Adomian分解算法,研究了分数阶简化Lorenz系统的数值解.研究发现,该算法与预估-校正算法相比,求解结果更准确,所耗计算资源和内存资源更少,求解整数阶系统时较Runge-Kutta算法更准确;利用Adomian算法得到的分数... 详细信息

根据分数阶微分定义,采用Adomian分解算法,研究了分数阶简化Lorenz系统的数值解.研究发现,该算法与预估-校正算法相比,求解结果更准确,所耗计算资源和内存资源更少,求解整数阶系统时较Runge-Kutta算法更准确;利用Adomian算法得到的分数阶简化Lorenz系统出现混沌的最小阶数为1.35,比利用预估-校正算法得到的最小阶2.79更小.采用相图、分岔图分析了该系统的动力学特性,基于谱熵算法(SE)和C0算法分析了该系统的复杂度.结果表明,复杂度结果和分岔图一致,说明系统的复杂度同样能反映出系统动力学特性;复杂度随阶数q的增加呈总体减小的趋势,而混沌态时系统参数c变化对系统复杂度影响不大.为分数阶混沌系统应用于信息加密、保密通信领域提供了理论与实验依据.

关键词：分数阶微积分 Adomian分解算法简化Lorenz系统复杂度

统一混沌系统与其变形系统间的间歇反馈同步控制

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电子与信息学报 2009年第1期31卷 71-74页

作者：孙克辉尚芳钟科盛喆中南大学物理科学与技术学院长沙410083 中南大学数学与统计学院长沙410083

采用间歇反馈控制方法,研究了统一混沌系统与其变形系统间的同步控制问题。通过合理设计间歇反馈控制器,将同步问题转化为误差动力学系统方程在原点处的收敛问题。根据连续系统的稳定性准则及相关实验,推导出了满足同步条件的同步定理... 详细信息

采用间歇反馈控制方法,研究了统一混沌系统与其变形系统间的同步控制问题。通过合理设计间歇反馈控制器,将同步问题转化为误差动力学系统方程在原点处的收敛问题。根据连续系统的稳定性准则及相关实验,推导出了满足同步条件的同步定理。分析了初始值X(0)和Y(0)、反馈系数k、比例因子D、步长h以及统一系统参数α对同步系统的同步性能的影响。最后,采用间隙反馈同步方案,设计了一个混沌掩盖保密通信系统,并进行了仿真研究。仿真实验研究证明了该同步方法的有效性。

关键词：混沌同步间歇反馈控制统一混沌系统混沌掩盖

Research on ECMS Based on Segmented Path Braking Energy Recovery in a Fuel Cell Vehicle

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Energy Engineering 2024年第1期121卷 95-110页

作者： Wen sun Meijing Li Guoxiang Li ke sun Shuzhan Bai School of Energy and Power Engineering Shandong UniversityJinan250061China Automotive Research Institute China National Heavy Duty Truck Group Co.Ltd.Jinan250061China

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal combustion engines in *** fuel cells cannot recover energy and have a slow dynamic response,they need to be used with different power *** efficient energy management strategies to achieve excellent fuel economy is the goal of *** paper proposes an adaptive equivalent fuel minimum consumption strategy(AECMS)to solve the problem of the poor economy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional *** this method,the kinematics interval is used to update the equivalent factor by considering the penalty term of energy recovery on SOC ***,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy *** results under the New European Driving Cycle show that compared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel economy by 1.7%while ensuring vehicle power and increases SOC by 30%.

关键词： Fuel cell PEMFC electric vehicle equivalent consumption minimization strategy

Evaluation of the Effectiveness of“5E”Comprehensive Injury Prevention Strategy for Fall Prevention Among the Rural Elderly—Six Pilot Villages,Yunnan Province and Chongqing Municipality,China,2018–2023

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China CDC weekly 2024年第14期6卷 277-281页

作者： Fujin sun Rong Luo hui Han National Center for Women and Children’s Health Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?The mortality rate and disease burden associated with falls among the elderly in China are on the *** can play a crucial role in preventing and managing *** is added by this report?The application of the“5E”injury prevention strategy led to a decrease in both the occurrence of falls and the likelihood of subsequent *** physical activity and maintaining a positive outlook were identified as protective measures against falls,while sleep issues and hearing impairment were found to increase the risk of *** are the implications for public health practice?The group-based comprehensive intervention strategy is crucial as it offers an innovative intervention model and empirical evidence for decreasing fall rates among elderly individuals living in rural areas.

关键词： Chongqing Rural prevention