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Dengue epidemic in China before 1978

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贫困所致传染病(英文) 2024年第5期13卷 1-4页

作者： Guo Xiang Chen haiyang Lin Ruifeng Liu Xiaohua Li meng Ge Liu Deng Wenting Wu Rangke Zhou Xiaohong Institute of Tropical Medicine Department of Pathogen Biology School of Public Health Southern Medical University Guangdong Provincial Key Laboratory of Tropical Disease Research Key Laboratory of Prevention and Control for Emerging Infectious Diseases of Guangdong Higher Institutes Key Laboratory of Infectious Diseases Research in South China Ministry of Education Guangzhou Guangdong China Department of Rheumatology and Immunology Nanfang Hospital Southern Medical University Guangzhou China Department of Traditional Chinese Internal Medicine School of Traditional Chinese Medicine Southern Medical University Guangzhou China The School of Foreign Studies Southern Medical University Guangzhou China

Dengue, an acute febrile disease transmitted byAedes mosquitoes, is caused by the dengue virus (DENV), presenting a formidable challenge to global public health. By examining clues from ancient Chinese books and conducting a comprehensive review, this study elucidates the characteristics of potential dengue epidemics in China prior to 1978. This evidence indicates that China may not have experience dengue epidemics before 1840. During 1840-1949, however, it experienced a noticeable dengue occurrence and prevalence in the 1870s, 1920s, and 1940s. Then from 1949 to 1978, only sporadic reports were accounted. The disparity in the frequency of dengue occurrences across three time periods suggests that the persistent characteristic of dengue epidemics in China primarily arises from imported cases resulting from international exchanges, subsequently leading to local outbreaks influenced by global epidemic trend. This research offers a novel perspective on retrospectively examining the historical trajectory of dengue epidemics and provides valuable insights into exploration of DENV epidemic patterns.

关键词： Dengue virus Comprehensive review Epidemics Ancient literature

A MODIFIED VARIABLE-PENALTY ALTERNATING DIRECTIONS METHOD FOR MONOTONE VARIATIONAL INEQUALITIES

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Journal of Computational Mathematics 2003年第4期21卷 495-504页

作者： Bing-shengHe Sheng-liWang haiyang DepartmentofMathematics NanjingUniversityNanjing210093China DepartmentofCivilEngineering TheHongKongUniversityofScience~TechnologyClearWaterBayKowloonHongKong

Alternating directions method is one of the approaches for solving linearly constrained separate monotone variational inequalities. Experience on applications has shown that the number of iteration significantly depends on the penalty for the system of linearly constrained equations and therefore the method with variable penalties is advantageous in practice. In this paper, we extend the Kontogiorgis and Meyer method [12] by removing the monotonicity assumption on the variable penalty matrices. Moreover, we introduce a self-adaptive rule that leads the method to be more efficient and insensitive for various initial penalties. Numerical results for a class of Fermat-Weber problems show that the modified method and its self-adaptive technique are proper and necessary in practice.

关键词： Monotone variational inequalities Alternating directions method Fermat-Weber problem.

A Deep Reinforcement Learning-Based Power Control Scheme for the 5G Wireless Systems

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China Communications 2023年第10期20卷 109-119页

作者： Renjie Liang haiyang Lyu Jiancun Fan School of Electronic and Information Engineering Xi’an Jiaotong UniversityXi’anShaanxi 710049China School of Cyber Science and Engineering Xi’an Jiaotong UniversityXi’anShaanxi 710049China

In the fifth generation(5G)wireless system,a closed-loop power control(CLPC)scheme based on deep Q learning network(DQN)is introduced to intelligently adjust the transmit power of the base station(BS),which can improve the user equipment(UE)received signal to interference plus noise ratio(SINR)to a target threshold ***,the selected power control(PC)action in DQN is not accurately matched the fluctuations of the wireless *** the experience replay characteristic of the conventional DQN scheme leads to a possibility of insufficient training in the target deep neural network(DNN).As a result,the Q-value of the sub-optimal PC action exceed the optimal *** solve this problem,we propose the improved DQN *** the proposed scheme,we add an additional DNN to the conventional DQN,and set a shorter training interval to speed up the training of the DNN in order to fully train ***,the proposed scheme can ensure that the Q value of the optimal action remains *** multiple episodes of training,the proposed scheme can generate more accurate PC actions to match the fluctuations of the wireless *** a result,the UE received SINR can achieve the target threshold range faster and keep more *** simulation results prove that the proposed scheme outperforms the conventional schemes.

关键词： reinforcement learning closed-loop power control(CLPC) signal-to-interference-plusnoise ratio(SINR)

Shear behavior of intact granite under thermo-mechanical coupling and three-dimensional morphology of shear-formed fractures

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 523-537页

作者： Bing Chen Baotang Shen haiyang Jiang State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao266590China CSIRO Mineral Resources Queensland Centre for Advanced Technologies1 Technology CourtPullenvaleQLD4069Australia No.1 Institute of Geology and Mineral Resource Exploration of Shandong Province Jinan250010China College of New Energy and Environment Jilin UniversityChangchun130012China

The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine *** the effect of a continuous engineering disturbance,shear-formed fractures are prone to secondary instability,posing a severe threat to deep *** numerous studies regarding three-dimensional(3D)morphologies of fracture surfaces have been conducted,the understanding of shear-formed fractures under TM coupling conditions is *** this study,direct shear tests of intact granite under various TM coupling conditions were conducted,followed by 3D laser scanning tests of shear-formed *** results demonstrated that the peak shear strength of intact granite is positively correlated with the normal stress,whereas it is negatively correlated with the *** internal friction angle and cohesion of intact granite significantly decrease with an increase in the *** anisotropy,roughness value,and height of the asperities on the fracture surfaces are reduced as the normal stress increases,whereas their variation trends are the opposite as the temperature *** macroscopic failure mode of intact granite under TM coupling conditions is dominated by mixed tensileeshear and shear *** the normal stress increases,intragranular fractures are developed ranging from a local to a global distribution,and the macroscopic failure mode of intact granite changes from mixed tensileeshear to shear ***,3D morphological characteristics of the asperities on the shear-formed fracture surfaces were analyzed,and a quadrangular pyramid conceptual model representing these asperities was proposed and sufficiently verified.

关键词： Thermo-mechanical(TM)coupling Peak shear strength Three-dimensional(3D)morphological characterization Failure mode Quadrangular pyramid model

Recent progress of residual stress measurement methods: A review

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Chinese Journal of Aeronautics 2021年第2期34卷 54-78页

作者： Jiang GUO haiyang FU Bo PAN Renke KANG Key Laboratory for Precision and Non-traditional Machining of Ministry of Education Dalian University of TechnologyDalian 116024China

Residual stress is one of the main factors affecting the mechanical properties of materials, such as their strength, plasticity and surface integrity. For instance, tensile stress conditions can adversely affect material performance or component life, while compressive stress conditions can improve material fatigue strength. During the processing of integrated aviation structures, machining deformation caused by residual stress has become one of the most prominent manufacturing problems. Therefore, it is very important to measure and evaluate the stress for real *** paper reviews the research of residual stress measurement methods over the past five years by classifying them according to the measurement methods appearing in each stage. The existing problems and difficulties of each measurement technology are summarized, and future trends are forecasted. This paper provides a reference for further in-depth study of residual stress measurement technologies.

关键词： Destructive testing Future trends Measurement Nondestructive testing Residual stress

Service composition based on discrete particle swarm optimization in military organization cloud cooperation

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Journal of Systems Engineering and Electronics 2016年第3期27卷 590-601页

作者： An Zhang haiyang Sun Zhili Tang Yuan Yuan School of Aeronautics Northwestern Polytechnical University School of Electronics and Information Northwestern Polytechnical University

This paper addresses the problem of service composition in military organization cloud cooperation（MOCC）. Military service providers（MSP） cooperate together to provide military resources for military service users（MSU）. A group of atom services, each of which has its level of quality of service（QoS）, can be combined together into a certain structure to form a composite service. Since there are a large number of atom services having the same function, the atom service is selected to participate in the composite service so as to fulfill users＇ will. In this paper a method based on discrete particle swarm optimization（DPSO） is proposed to tackle this problem. The method aims at selecting atom services from service repositories to constitute the composite service, satisfying the MSU＇s requirement on QoS. Since the QoS criteria include location-aware criteria and location-independent criteria, this method aims to get the composite service with the highest location-aware criteria and the best-match location-independent criteria. Simulations show that the DPSO has a better performance compared with the standard particle swarm optimization（PSO） and genetic algorithm（GA）.

关键词： service composition cloud cooperation discrete particle swarm optimization(DPSO)

Numerical insight into heat transfer enhancement by granules inner-migration in a moving bed:A performance comparison between slanted-stick and plow-shaped agitator

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Particuology 2024年第6期89卷 109-116页

作者： Binfan Jiang Hao Pei Dehong Xia haiyang Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Shunde Graduate School of University of Science and Technology Beijing Guangdong 528399China Jianlong Group&USTB Joint Laboratory Beijing 100083China

Waste heat recovery of high-temperature granules is one of the most promising sustainable energy supply and carbon reduction ways for industry.A moving bed indirect heat exchanger(MBIHE)with inner-migration was proposed for granular heat *** migration and the enhanced heat transfer induced by two types of agitators(i.e.,agitator with slanted stick A_(s)and with plow-shaped surface A_(p))in the MBIHE are analyzed based on DEM coupled with *** to the effective agitation,the average heat transfer coefficient in the granule side is enhanced to∼3 times compared to that without *** heat recovery efficiency in the moving bed reached more than 70%with the agitations of either A_(s)or A_(p).The heat efficiency of A_(s)is∼7%higher than that of A_(p),but with at least 60%greater rotational *** ensure reliable agitation,the A_(p)is suggested to be adopted in the MBIHE to induce granule migration.

关键词： Waste heat recovery High-temperature granule Granule migration Heat transfer enhancement Industry energy saving

A High Order Control Volume Finite Element Method for Transient Heat Conduction Analysis of Multilayer Functionally Graded Materials with Mixed Grids

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Journal of Thermal Science 2020年第1期29卷 144-158页

作者： LIU Qi MING Pingjian ZHAO haiyang ZHANG Wenping College of power and energy engineering Harbin Engineering University

This paper describes a new two-dimensional(2-D)control volume finite element method(CV-FEM)for transient heat conduction in multilayer functionally graded materials(FGMs).To deal with the mixed-grid problem,9-node quadrilateral grids and 6-node triangular grids are *** unknown temperature and material properties are stored at the *** using quadratic triangular grids and quadratic quadrilateral grids,the present method offers greater geometric flexibility and the potential for higher accuracy than the linear *** properties of the FGMs are described by exponential,quadratic and trigonometric grading *** numerical tests are studied to demonstrate the performance of the developed ***,the present CV-FEM with mixed high-order girds provides a higher accuracy than the linear CV-FEM based on the same grid ***,the material properties defined location is proved to have a significant effect on the accuracy of the numerical ***,the present method provides better numerical solutions than the conventional FEM for the FGMs in conjunction with course high-order ***,the present method is also capable of analysis of transient heat conduction in multilayer FGM.

关键词： finite volume method functionally graded materials transient heat conduction

Freestanding nanosheets of 1T-2H hybrid MoS_(2) as electrodes for efficient sodium storage

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Journal of Materials Science & Technology 2021年第8期67卷 237-242页

作者： haiyang Yu Zhenzhu Wang Jiangfeng Ni Liang Li School of Physical Science and Technology Center for Energy Conversion Materials&PhysicsJiangsu Key Laboratory of Thin FilmsSoochow UniversitySuzhou 215006China

Molybdenum disulfide(MoS_(2)) is a promising electrode material for sodium-ion batteries as it offers a large capacity through a distinct conversion ***,the electrochemical potential of MoS_(2) is often restrained by the poor conductivity as the dominant 2 H phase is a semiconductor while the metallic1 T phase is thermodynamically *** this work,we report a hybrid design and material preparation of freestanding nanosheets of MoS_(2) composed of both 1 T and 2 H phases based on mild hydrothermal *** introduction of the metallic 1 T-MoS_(2) phase into 2 H-MoS_(2) and their intimate hybridization enable a significant improvement in electronic conductivity,while the freestanding architecture avoids possible electrochemical *** used as electrodes for sodium storage,such a hybrid MoS_(2) affords a high capacity of~500 mA h g^(-1) at 0.5 A g^(-1) after 300 cycles,and retains capacity of~200 mA h g^(-1) at a high current rate of 4 A g^(-1),thus demonstrating their potential in high-performance battery applications.

关键词： Molybdenum disulfide Sodium-ion battery Hybrid Finite element modeling