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International Journal of Disaster Risk Science 2024年第2期15卷 277-289页

作者： shuai zhou Crystal Kwan Department of Applied Social Sciences The Hong Kong Polytechnic UniversityHong Kong 999077China

Despite the well-documented impacts of single natural hazards like earthquakes, less is known about the psychological adaptation to multiple natural hazards, particularly in rural areas. This study investigated the associations of multiple natural hazards with depression among Chinese adults. Data were retrieved from the China Family Panel Studies conducted during 2010–2018. With a sample of 11,633 Chinese adults, multilevel logistic regression was employed to examine the relationships between natural hazard exposure and depression in the total sample and different age groups. Overall, experiencing four or more natural hazards was associated with a higher risk of being depressed. Regarding hazard type, the number of hydrometeorological and biological hazards was associated with a higher likelihood of depression, whereas the number of geologic and other hazards was related to a lower risk of depression. Middle-aged adults from villages were more likely to be affected by natural hazard exposure than older and younger adults. The findings of this study show that cumulative exposure to natural hazards can generate lasting effects on depressive symptoms, particularly in middle adulthood. The findings also suggest that older adults from rural areas may have accumulated more resilience to mitigate the adverse well-being effects of hazard events. Policies and interventions should enhance disaster awareness and preparation for aging residents from multi-hazard communities.

关键词： Age differences China Depressive symptoms Multi-hazard communities Natural hazard exposure

The Prediction of Self-Healing Capacity of Bacteria-Based Concrete Using Machine Learning Approaches

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Computers, Materials & Continua 2019年第4期59卷 57-77页

作者： Xiaoying Zhuang shuai zhou Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam College of Materials Science and Engineering Chongqing UniversityChongqing400045China Institute of Continuum Mechanics Leibniz University HannoverHannover30167Germany

Advances in machine learning(ML)methods are important in industrial engineering and attract great attention in recent ***,a comprehensive comparative study of the most advanced ML algorithms is *** integrated ML approaches for the crack repairing capacity of the bacteria-based self-healing concrete are proposed and *** ML algorithms,including the Support Vector Regression(SVR),Decision Tree Regression(DTR),Gradient Boosting Regression(GBR),Artificial Neural Network(ANN),Bayesian Ridge Regression(BRR)and Kernel Ridge Regression(KRR),are adopted for the relationship modeling to predict crack closure percentage(CCP).Particle Swarm Optimization(PSO)is used for the hyper-parameters *** importance of parameters is *** is demonstrated that integrated ML approaches have great potential to predict the CCP,and PSO is efficient in the hyperparameter *** research provides useful information for the design of the bacteria-based self-healing concrete and can contribute to the design in the rest of industrial engineering.

关键词： Bacteria self-healing concrete crack closure percentage machine learning prediction

Micromechanical study of loading rate effects between a hole and a crack

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Underground Space 2019年第1期4卷 22-30页

作者： shuai zhou Xiaoying Zhuang Institute of Continuum Mechanics Leibniz University HannoverHannover 30167Germany Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The interactions between defects are important in *** micromechanical interactions between a circular hole and a pre-existing crack under uniaxial compression with different loading rates are investigated by the discrete element method(DEM).The crack initiation,crack propagation,and crack coalescence at different loading rates are *** loading rates influence the primary as well as secondary *** the primary and secondary cracks disturb the stress field and displacement *** DEM simulation explains the initiation position of the primary and secondary *** evolution of the displacement field and the stress field at different loading rates is analyzed.A new displacement field type is *** hole is easier to be broken by compression at higher loading rates while it tends to be broken by the coalescence crack at lower loading *** high loading rates lead to shielding effects of the hole on the pre-existing crack.

关键词： Rock Defect Loading rate Cracking processes DEM Compressive loading

Characterization of Loading Rate Effects on the Interactions Between Crack Growth and Inclusions in Cementitious Material

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Computers, Materials & Continua 2018年第12期57卷 417-446页

作者： shuai zhou Xiaoying Zhuang Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam College of Materials Science and Engineering Chongqing UniversityChongqingChina Leibniz Universität Hannover Appelstr.1130167HannoverGermany

The microcapsule-enabled cementitious material is an appealing building material and it has been attracting increasing research *** considering microcapsules as dissimilar inclusions in the material,this paper employs the discrete element method(DEM)to study the effects of loading rates on the fracturing behavior of cementitious specimens containing the inclusion and the *** numerical model was first developed and validated based on experimental *** is then used to systematically study the initiation,the propagation and the coalescence of cracks in inclusion-enabled cementitious *** study reveals that the crack propagation speed,the first crack initiation stress,the coalescence stress,the compressive strength and the ultimate strain increase with the loading *** initiation position,the propagation direction,the cracking length and the type of the initiated cracks are influenced by the loading *** new crack coalescence patterns are *** is easier to cause the coalescence between the circular void and a propagating crack at a slow loading rate than at a fast loading rate.

关键词： Microcapsule loading rate cracking processes DEM compressive loading

Recursive Feature Elimination Based Feature Selection in Modulation Classification for MIMO Systems

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Chinese Journal of Electronics 2023年第4期32卷 785-792页

作者： zhou shuai LI Tao LI Yongzhao School of Telecommunications Engineering Xidian University

The feature-based(FB) algorithms are widely used in modulation classification due to their low complexity. As a prerequisite step of FB, feature selection can reduce the computational complexity without significant performance loss. In this paper, according to the linear separability of cumulant features, the hyperplane of the support vector machine is used to classify modulation types, and the contribution of different features is ranked through the weight vector. Then, cumulant features are selected using recursive feature elimination(RFE) to identify the modulation type employed at the transmitter. We compare the performance of the proposed algorithm with existing feature selection algorithms and analyze the complexity of all the mentioned algorithms. Simulation results verify that the proposed RFE algorithm can optimize the selection of the features to realize modulation recognition and improve identification efficiency.

关键词： Transmitters Simulation Modulation Support vector machine classification Feature extraction Classification algorithms Computational complexity

The Interaction between Microcapsules with Different Sizes and Propagating Cracks

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Computers, Materials & Continua 2021年第4期67卷 577-593页

作者： Xiaoying Zhuang Hung Nguyen-Xuan shuai zhou College of Materials Science and Engineering Chongqing UniversityChongqing400045China Institute of Continuum Mechanics Leibniz University HannoverHannoverGermany Department of Geotechnical Engineering Tongji UniversityShanghaiChina CIRTech Institute Ho Chi Minh City University of Technology(HUTECH)Ho Chi Minh CityVietnam Department of Architectural Engineering Sejong University209 Neungdong-roGwangjin-guSeoul05006Korea

The microcapsule-contained self-healing materials are appealing since they can heal the cracks automatically and be effective for a long *** many experiments have been carried out,the influence of the size of microcapsules on the self-healing effect is still not well *** study uses the two-dimensional discrete element method(DEM)to investigate the interaction between one microcapsule and one *** influence of the size of microcapsules is *** potential healing time and the influence of the initial damage are *** results indicate that the coalescence crack is affected by the size of *** elastic modulus,the compressive strength and the coalescence stress decrease with the rising radius of *** initial damage in experiments should be greater than 95%of the compressive strength to enhance the self-healing *** large microcapsules require slight initial *** a new type of displacement field near the crack and a new category of coalescence crack are *** influence of sizes of holes on the cracking behavior of concrete with a circular hole and a pre-existing crack is clarified.

关键词： Microcapsule size cracking processes DEM

Polydimethylsiloxane assisted supercritical CO2 foaming behavior of high melt strength polypropylene grafted with styrene

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Frontiers of Chemical Science and Engineering 2016年第3期10卷 396-404页

作者： Weixia Wang shuai zhou Zhong Xin Yaoqi Shi Shicheng Zhao Shanghai Key Laboratory of Multiphase Materials Chemical Engineering East China University of Science and Technology Shanghai 200237 China State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai 200237 China Shanghai Key Laboratory of Catalysis Technology for Polyolefin Shanghai Research Institute of Chemical Industry Shanghai 200062 China

Foamable high melt strength polypropylene （HMSPP） was prepared by grafting styrene （St） onto polypropylene （PP） and simultaneously introducing poly- dimethylsiloxane （PDMS） through a one-step melt extru- sion process. The effect of PDMS viscosity on the foaming behavior of HMSPP was systematically investigated using supercritical CO2 as the foaming agent. The results show that the addition of PDMS has little effect on the grafting reaction of St and HMSPP exhibits enhanced elastic response and obvious strain hardening effect. Though the CO2 solubility of HMSPP with PDMS （PDMS-HMSPP） is lower than that of HMSPP without PDMS, especially for PDMS with low viscosity, the PDMS-HMSPP foams exhibit narrow cell size distribution and high cell density. The fracture morphology of PDMS-HMSPP shows that PDMS with low viscosity disperses more easily and uniformly in HMSPP matrix, leading to form small domains during the extrusion process. These small domains act as bubble nucleation sites and thus may be responsible for the improved foaming performance of HMSPP.

关键词： high melt strength polypropylene (HMSPP),polydimethylsiloxane (PDMS) supercritical CO2 foaming behavior

Microcapsule-enabled self-healing concrete:A bibliometric analysis

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Frontiers of Structural and Civil Engineering 2023年第11期17卷 1611-1629页

作者： shuai zhou Zijian LI Kai LI Yue JIA Chong WANG Xiaoying ZHUANG College of Materials Science and Engineering Chongqing UniversityChongqing 400045China Department of Mathematics and Physics Leibniz Universität HannoverHannover 30167Germany Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

With the development of self-healing technology, the overall properties of the microcapsule-enabled selfhealingconcrete have taken a giant leap. In this research, a detailed assessment of current research on the microcapsuleenabledself-healing concrete is conducted, together with bibliometric analysis. In the bibliometric analysis, variousindicators are considered. The current state of progress regarding self-healing concrete is assessed, and an analysis of thetemporal distribution of documents, organizations and countries of literature is conducted. Later, a discussion of thecitations is analyzed. The research summarizes the improvements of microcapsule-enabled self-healing cementitiouscomposites and provides a concise background overview.

关键词： microcapsule self-healing concrete bibliographic analysis

RNA Interference-Mediated Downregulation of sAC Gene Inhibits Sperm Hyperactivation in Male Rats(Rattus norvegicus)

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Journal of Integrative Agriculture 2014年第2期13卷 394-401页

作者： YU Jing JIANG Xiao-qiang zhou shuai WANG Gen-lin College of Animal Science and Technology Nanjing Agricultural University

Hyperactivation is one of the most critical parts for fertilization, cAMP generated by soluble adenylyl cyclase （sAC） is necessary to activate sperm and is a prerequisite for sperm hyperactivation. The aim of this study is to investigate the function of sAC in hyperactivation in male rats. Four siRNAs of sAC gene were designed and separately transformed into rat sperm using electrotransformation method. Cultured for 12 and 24 h, physiological and biochemical indexes of these sperm were analyzed, and the expressions of some hyperactivation-related genes were detected using real-time PCR. We demonstrated 26.3-30.8% and 49.1-50.5% reduction in sAC at the protein by Western blot and mRNA levels by real-time PCR, respectively. The results showed that two siRNAs, Actb-717 and Actb-4205, were the best RNAi sites for silencing sAC. The VCL （curvilinear velocity） and ALH （amplitude of lateral head displacement） of RNA interference （RNAi）-transfected sperm were reduced, cAMP and protein phosphorylation in RNAi transfected sperm were also decreased. The hyperactivation-related genes, such as CatSper2, LDHC and PKA, were downregulated in the sperm, which sAC was knockdown. These findings demonstrated that sAC might play a critical role in cAMP signaling in the rat sperm hyperactivation, and downregulated sAC gene might prevent the expression of these hyperactivation-ralated genes resulting in sperm dysfunction. These findings suggest that these hyperactivation-ralated genes and sAC are functionally related in sperm hyperactivation and sAC falls into an expanding group of sperm proteins that appear to be promising targets for the development of male contraceptives.

关键词： Rattus norvegicus hyperactivation sAC RNAi male contraceptives

Double Update Intelligent Strategy for Permanent Magnet Synchronous Motor Parameter Identification

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Computers, Materials & Continua 2023年第2期74卷 3391-3404页

作者： shuai zhou Dazhi Wang Mingtian Du Ye Li Shuo Cao School of Information Science and Engineering Northeastern UniversityShenyang110819China Department of Mechanical Engineering The University of MelbourneVictoria3010Australia College of Information Engineering Shenyang Polytechnic CollegeShenyang110045China

The parameters of permanent magnet synchronous motor(PMSM)affect the performance of vector control servo *** of the complexity of nonlinear model of PMSM,it is very difficult to identify the parameters of *** at the problems of large amount of data calculation,low identification accuracy and poor robustness in the process of multi parameter identification of permanent magnet synchronous motor,this paper proposes a weighted differential evolutionary particle swarm optimization algorithm based on double update *** introducing adaptive judgment factor to control the proportion of weighted difference evolution(WDE)algorithm and particle swarm optimization(PSO)algorithm in each iteration process,and consider using PSO algorithm or WDE algorithm to update individuals according to the probability *** individuals obtained from WDE operation are used to guide the individual evolution process in PSO operation through the information *** proposed WDEPSO algorithm can ensure the diversity and effectiveness of the individual evolution of the *** algorithm is applied to parameter identification of PMSMdrive *** simulation results show that the proposed algorithm has better convergence performance and has strong robustness,parameter identification of permanent magnet synchronous motor based on proposed method does not need to rely on more data sheet on the motor design value,can motor stator resistance identification at the same time,the rotor flux linkage,d/q-axis inductance and electrical parameters,and can effectively track the parameters value.

关键词： PMSM parameter identification WDE PSO WDEPSO