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Deep Reinforcement Learning-Based Task Offloading and Service Migrating Policies in Service Caching-Assisted Mobile Edge Computing

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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

Novel Woods-Saxon stochastic resonance system for weak signal detection

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Chinese Physics B 2020年第4期29卷 190-198页

作者： Yong-hui Zhou Xue-Mei Xu Lin-Zi Yin Yi-Peng Ding Jia-Feng Ding ke-hui sun School of Physics and Electronics Central South UniversityChangsha 410083China

We propose a joint exponential function and Woods–Saxon stochastic resonance(EWSSR)*** change of a single parameter in the classical stochastic resonance model may cause a great change in the shape of the potential function,it is difficult to obtain the optimal output signal-to-noise ratio by adjusting one *** the novel system,the influence of different parameters on the shape of the potential function has its own emphasis,making it easier for us to adjust the shape of the potential *** system can obtain different widths of the potential well or barrier height by adjusting one of these parameters,so that the system can match different types of input signals *** adjusting the system parameters,the potential function model can be transformed between the bistable model and the monostable *** potential function of EWSSR has richer shapes and geometric *** effects of parameters,such as the height of the barrier and the width of the potential well,on SNR are studied,and a set of relatively optimal parameters are ***,the EWSSR model is compared with other classical stochastic resonance *** experiments show that the proposed EWSSR model has higher SNR and better noise immunity than other classical stochastic resonance ***,the EWSSR model is applied to the detection of actual bearing fault signals,and the detection effect is also superior to other models.

关键词： stochastic resonance weak signal detection a joint exponential function and Woods-Saxon stochastic resonance signal-to-noise ratio

Asymmetric stochastic resonance under non-Gaussian colored noise and time-delayed feedback

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Chinese Physics B 2020年第5期29卷 155-164页

作者： Ting-Ting Shi Xue-Mei Xu ke-hui sun Yi-Peng Ding Guo-Wei Huang School of Physics and Electronics Central South UniversityChangsha 410083China

Based on adiabatic approximation theory,in this paper we study the asymmetric stochastic resonance system with time-delayed feedback driven by non-Gaussian colored *** analytical expressions of the mean first-passage time(MFPT)and output signal-to-noise ratio(SNR)are derived by using a path integral approach,unified colored-noise approximation(UCNA),and small delay *** effects of time-delayed feedback and non-Gaussian colored noise on the output SNR are ***,three types of asymmetric potential function characteristics are thoroughly *** they are well-depth asymmetry(DASR),well-width asymmetry(WASR),and synchronous action of welldepth and well-width asymmetry(DWASR),*** conclusion of this paper is that the time-delayed feedback can suppress SR,however,the non-Gaussian noise deviation parameter has the opposite ***,the correlation time plays a significant role in improving SNR,and the SNR of asymmetric stochastic resonance is higher than that of symmetric stochastic *** experiments demonstrate that the appropriate parameters can make the asymmetric stochastic resonance perform better to detect weak signals than the symmetric stochastic resonance,in which no matter whether these signals have low frequency or high frequency,accompanied by strong or weak noise.

关键词： asymmetric stochastic resonance time-delayed feedback non-Gaussian colored noise weak signal detection

Implication of two-coupled tri-stable stochastic resonance in weak signal detection

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Chinese Physics B 2018年第3期27卷 260-266页

作者： Quan-Quan Li Xue-Mei Xu Lin-Zi Yin Yi-Peng Ding Jia-Feng Ding ke-hui sun School of Physics and Electronics Central South University Changsha 410083 China

Stochastic resonance （SR） has been proved to be an effective approach to extract weak signals overwhelmed in noise. However, the detection effect of current SR models is still unsatisfactory. Here, a coupled tri-stable stochastic resonance （CTSSR） model is proposed to further increase the output signal-to-noise ratio （SNR） and improve the detection effect of SR. The effects of parameters a, b, c, and r in the proposed resonance system on the SNR are studied, by which we determine a set of parameters that is relatively optimal to implement a comparison with other classical SR models. Numerical experiment results indicate that this proposed model performs better in weak signal detection applications than the classical ones with merits of higher output SNR and better anti-noise capability.

关键词： stochastic resonance extracting weak signals signal-to-noise ratio (SNR) detection effect

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

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