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Smart prediction of liquefaction-induced lateral spreading 被引量:1
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作者 Muhammad Nouman Amjad Raja Tarek Abdoun Waleed El-Sekelly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2310-2325,共16页
The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(... The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(GEP).Based on statistical reasoning,individual models were developed for two topographies:free-face and gently sloping ground.Along with a comparison with conventional approaches for predicting the Dh,four additional regression-based soft computing models,i.e.Gaussian process regression(GPR),relevance vector machine(RVM),sequential minimal optimization regression(SMOR),and M5-tree,were developed and compared with the GEP model.The results indicate that the GEP models predict Dh with less bias,as evidenced by the root mean square error(RMSE)and mean absolute error(MAE)for training(i.e.1.092 and 0.815;and 0.643 and 0.526)and for testing(i.e.0.89 and 0.705;and 0.773 and 0.573)in free-face and gently sloping ground topographies,respectively.The overall performance for the free-face topology was ranked as follows:GEP>RVM>M5-tree>GPR>SMOR,with a total score of 40,32,24,15,and 10,respectively.For the gently sloping condition,the performance was ranked as follows:GEP>RVM>GPR>M5-tree>SMOR with a total score of 40,32,21,19,and 8,respectively.Finally,the results of the sensitivity analysis showed that for both free-face and gently sloping ground,the liquefiable layer thickness(T_(15))was the major parameter with percentage deterioration(%D)value of 99.15 and 90.72,respectively. 展开更多
关键词 Lateral spreading Intelligent modeling Gene expression programming(GEP) Closed-form solution Feature importance
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Individual dynamics and local heterogeneity provide a microscopic view of the epidemic spreading
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作者 朱友源 沈瑞哲 +1 位作者 董昊 王炜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期656-663,共8页
The COVID-19 pandemic has caused severe global disasters,highlighting the importance of understanding the details and trends of epidemic transmission in order to introduce efficient intervention measures.While the wid... The COVID-19 pandemic has caused severe global disasters,highlighting the importance of understanding the details and trends of epidemic transmission in order to introduce efficient intervention measures.While the widely used deterministic compartmental models have qualitatively presented continuous “analytical” insight and captured some transmission features,their treatment usually lacks spatiotemporal variation.Here,we propose a stochastic individual dynamical(SID)model to mimic the random and heterogeneous nature of epidemic propagation.The SID model provides a unifying framework for representing the spatiotemporal variations of epidemic development by tracking the movements of each individual.Using this model,we reproduce the infection curves for COVID-19 cases in different areas globally and find the local dynamics and heterogeneity at the individual level that affect the disease outbreak.The macroscopic trend of virus spreading is clearly illustrated from the microscopic perspective,enabling a quantitative assessment of different interventions.Seemingly,this model is also applicable to studying stochastic processes at the “meter scale”,e.g.,human society’s collective dynamics. 展开更多
关键词 Brownian motion epidemic spreading HETEROGENEITY
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Influence of network structure on spreading dynamics via tie range
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作者 李敏 宋玉蓉 +3 位作者 宋波 李汝琦 蒋国平 张晖 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期606-613,共8页
There are various phenomena of malicious information spreading in the real society, which cause many negative impacts on the society. In order to better control the spreading, it is crucial to reveal the influence of ... There are various phenomena of malicious information spreading in the real society, which cause many negative impacts on the society. In order to better control the spreading, it is crucial to reveal the influence of network structure on network spreading. Motifs, as fundamental structures within a network, play a significant role in spreading. Therefore, it is of interest to investigate the influence of the structural characteristics of basic network motifs on spreading dynamics.Considering the edges of the basic network motifs in an undirected network correspond to different tie ranges, two edge removal strategies are proposed, short ties priority removal strategy and long ties priority removal strategy. The tie range represents the second shortest path length between two connected nodes. The study focuses on analyzing how the proposed strategies impact network spreading and network structure, as well as examining the influence of network structure on network spreading. Our findings indicate that the long ties priority removal strategy is most effective in controlling network spreading, especially in terms of spread range and spread velocity. In terms of network structure, the clustering coefficient and the diameter of network also have an effect on the network spreading, and the triangular structure as an important motif structure effectively inhibits the spreading. 展开更多
关键词 network spreading network motifs tie range edge removal strategy
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Possible Cortical Spreading Depression Recorded Intraoperatively Following a Generalized Seizure: Illustrative Case
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作者 Greg Schaublin Romina Shirka +4 位作者 Nabil Azar Callan Broderick Jayson Neil George R. Lee Kiara Ebinger 《Neuroscience & Medicine》 2024年第3期119-128,共10页
Background: We present a compelling case fitting the phenomenon of cortical spreading depression detected by intraoperative neurophysiological monitoring (IONM) following an intraoperative seizure during a craniotomy ... Background: We present a compelling case fitting the phenomenon of cortical spreading depression detected by intraoperative neurophysiological monitoring (IONM) following an intraoperative seizure during a craniotomy for revascularization. Cortical spreading depression (CSD, also called cortical spreading depolarization) is a pathophysiological phenomenon whereby a wave of depolarization is thought to propagate across the cerebral cortex, creating a brief period of relative neuronal inactivity. The relationship between CSD and seizures is unclear, although some literature has made a correlation between seizures and a cortical environment conducive to CSD. Methods: Intraoperative somatosensory evoked potentials (SSEPs) and electroencephalography (EEG) were monitored continuously during the craniotomy procedure utilizing standard montages. Electrophysiological data from pre-ictal, ictal, and post-ictal periods were recorded. Results: During the procedure, intraoperative EEG captured a generalized seizure followed by a stepwise decrease in somatosensory evoked potential cortical amplitudes, compelling for the phenomenon of CSD. The subsequent partial recovery of neuronal function was also captured electrophysiologically. Discussion: While CSD is considered controversial in some aspects, intraoperative neurophysiological monitoring allowed for the unique analysis of a case demonstrating a CSD-like phenomenon. To our knowledge, this is the first published example of this phenomenon in which intraoperative neurophysiological monitoring captured a seizure, along with a stepwise subsequent reduction in SSEP cortical amplitudes not explained by other variables. 展开更多
关键词 Cortical spreading Depression ELECTROENCEPHALOGRAPHY Intraoperative Neurophysiological Monitoring SEIZURE
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DiriNet:An Estimation Network for Spectral Response Function and Point Spread Function
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作者 Ting Hu Siyuan Cheng Chang Liu 《Journal of Beijing Institute of Technology》 EI CAS 2024年第4期287-297,共11页
Hyper-and multi-spectral image fusion is an important technology to produce hyper-spectral and hyper-resolution images,which always depends on the spectral response function andthe point spread function.However,few wo... Hyper-and multi-spectral image fusion is an important technology to produce hyper-spectral and hyper-resolution images,which always depends on the spectral response function andthe point spread function.However,few works have been payed on the estimation of the two degra-dation functions.To learn the two functions from image pairs to be fused,we propose a Dirichletnetwork,where both functions are properly constrained.Specifically,the spatial response function isconstrained with positivity,while the Dirichlet distribution along with a total variation is imposedon the point spread function.To the best of our knowledge,the neural network and the Dirichlet regularization are exclusively investigated,for the first time,to estimate the degradation functions.Both image degradation and fusion experiments demonstrate the effectiveness and superiority of theproposed Dirichlet network. 展开更多
关键词 Dirichlet network point spread function spectral response function hyper-spectralimage multi-spectral image
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Adaptive Video Dual Domain Watermarking Scheme Based on PHT Moment and Optimized Spread Transform Dither Modulation
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作者 Yucheng Liang Ke Niu +2 位作者 Yingnan Zhang Yifei Meng Fangmeng Hu 《Computers, Materials & Continua》 SCIE EI 2024年第11期2457-2492,共36页
To address the challenges of video copyright protection and ensure the perfect recovery of original video,we propose a dual-domain watermarking scheme for digital video,inspired by Robust Reversible Watermarking(RRW)t... To address the challenges of video copyright protection and ensure the perfect recovery of original video,we propose a dual-domain watermarking scheme for digital video,inspired by Robust Reversible Watermarking(RRW)technology used in digital images.Our approach introduces a parameter optimization strategy that incre-mentally adjusts scheme parameters through attack simulation fitting,allowing for adaptive tuning of experimental parameters.In this scheme,the low-frequency Polar Harmonic Transform(PHT)moment is utilized as the embedding domain for robust watermarking,enhancing stability against simulation attacks while implementing the parameter optimization strategy.Through extensive attack simulations across various digital videos,we identify the optimal low-frequency PHT moment using adaptive normalization.Subsequently,the embedding parameters for robust watermarking are adaptively adjusted to maximize robustness.To address computational efficiency and practical requirements,the unnormalized high-frequency PHT moment is selected as the embedding domain for reversible watermarking.We optimize the traditional single-stage extended transform dithering modulation(STDM)to facilitate multi-stage embedding in the dual-domain watermarking process.In practice,the video embedded with a robust watermark serves as the candidate video.This candidate video undergoes simulation according to the parameter optimization strategy to balance robustness and embedding capacity,with adaptive determination of embedding strength.The reversible watermarking is formed by combining errors and other information,utilizing recursive coding technology to ensure reversibility without attacks.Comprehensive analyses of multiple performance indicators demonstrate that our scheme exhibits strong robustness against Common Signal Processing(CSP)and Geometric Deformation(GD)attacks,outperforming other advanced video watermarking algorithms under similar conditions of invisibility,reversibility,and embedding capacity.This underscores the effectiveness and feasibility of our attack simulation fitting strategy. 展开更多
关键词 Dual-domain H.264 group of pictures polar harmonic transform spread transform dither modulation
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Bearing Capacity Analysis of Spread Footing on Massif in the “Corniche Ouest” of the Dakar Peninsula (Senegal, West Africa)
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作者 Moussa Sawadogo Déthie Sarr Oustasse A. Sall 《Open Journal of Civil Engineering》 2024年第3期421-434,共14页
This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated usin... This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated using empirical, analytical and numerical approaches based on the parameters of the rock mass and the foundation. Laboratory tests were carried out on basanite, as well as on the other facies detected. The results of these studies give a range of allowable bearing capacity values varying between 1.92 and 11.39 MPa for the empirical methods and from 7.13 to 25.50 MPa for the analytical methods. A wide dispersion of results was observed according to the different approaches. This dispersion of results is explained by the use of different rock parameters depending on the method used. The allowable bearing capacity results obtained with varying approaches of calculation remain admissible to support the loads. On the other hand, the foundation calculations show acceptable settlement of the order of a millimeter for all the layers, especially in the thin clay layers resting on the bedrock at shallow depths, where the rigidity of the rock reduces settlement. 展开更多
关键词 Peninsula of Dakar Bearing Capacity Basanites Rock Mass spread Footings
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A Survey of Human-centered Intelligent Robots:Issues and Challenges 被引量:33
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作者 Wei He Zhijun Li C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 CSCD 2017年第4期602-609,共8页
Intelligent techniques foster the dissemination of new discoveries and novel technologies that advance the ability of robots to assist and support humans. The human-centered intelligent robot has become an important r... Intelligent techniques foster the dissemination of new discoveries and novel technologies that advance the ability of robots to assist and support humans. The human-centered intelligent robot has become an important research field that spans all of the robot capabilities including navigation, intelligent control, pattern recognition and human-robot interaction. This paper focuses on the recent achievements and presents a survey of existing works on human-centered robots. Furthermore, we provide a comprehensive survey of the recent development of the human-centered intelligent robot and discuss the issues and challenges in the field. 展开更多
关键词 human-centered robots human-robot interaction intelligent control NAVIGATION path planning pattern recognition
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Guest Editorial for Special Issue on Human-centered Intelligent Robots:Issues and Challenges 被引量:2
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作者 Zhijun Li C.L.Philip Chen Wei He 《IEEE/CAA Journal of Automatica Sinica》 CSCD 2017年第4期599-601,共3页
The special issue aims to address a broad spectrum of topics ranging from human-centered intelligent robots acting as a servant,secretary,or companion to intelligent robotic functions.The special issue publishes origi... The special issue aims to address a broad spectrum of topics ranging from human-centered intelligent robots acting as a servant,secretary,or companion to intelligent robotic functions.The special issue publishes original papers of innovative ideas and concepts,new discoveries,and novel applications and business models relevant to the field of human-centered intelligent robots.In this special issue,modeling,intelligent control, 展开更多
关键词 In Guest Editorial for Special Issue on human-centered Intelligent Robots:Issues and Challenges
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Channel Estimation for OTFS System over Doubly Spread Sparse Acoustic Channels 被引量:4
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作者 Yang Zhang Qunfei Zhang +1 位作者 Chengbing He Chao Long 《China Communications》 SCIE CSCD 2023年第1期50-65,共16页
This paper addresses sparse channels estimation problem for the generalized linear models(GLM)in the orthogonal time frequency space(OTFS)underwater acoustic(UWA)system.OTFS works in the delay-Doppler domain,where tim... This paper addresses sparse channels estimation problem for the generalized linear models(GLM)in the orthogonal time frequency space(OTFS)underwater acoustic(UWA)system.OTFS works in the delay-Doppler domain,where timevarying channels are characterized as delay-Doppler impulse responses.In fact,a typical doubly spread UWA channel is associated with several resolvable paths,which exhibits a structured sparsity in the delayDoppler domain.To leverage the structured sparsity of the doubly spread UWA channel,we develop a structured sparsity-based generalized approximated message passing(GAMP)algorithm for reliable channel estimation in quantized OTFS systems.The proposed algorithm has a lower computational complexity compared to the conventional Bayesian algorithm.In addition,the expectation maximum algorithm is employed to learn the sparsity ratio and the noise variance.Simulation and experimental results show that the proposed algorithm has superior performance and low computational complexity for quantized OTFS systems. 展开更多
关键词 OTFS doubly spread UWA channel delay-Doppler domain GAMP
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Functionalized alginate-based bioinks for microscale electrohydrodynamic bioprinting of living tissue constructs with improved cellular spreading and alignment 被引量:3
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作者 Zhennan Qiu Hui Zhu +3 位作者 Yutao Wang Ayiguli Kasimu Dichen Li Jiankang He 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第2期136-149,共14页
Bioprinting has been widely investigated for tissue engineering and regenerative medicine applications.However,it is still difficult to reconstruct the complex native cell arrangement due to the limited printing resol... Bioprinting has been widely investigated for tissue engineering and regenerative medicine applications.However,it is still difficult to reconstruct the complex native cell arrangement due to the limited printing resolution of conventional bioprinting techniques such as extrusion-and inkjet-based printing.Recently,an electrohydrodynamic(EHD)bioprinting strategy was reported for the precise deposition of well-organized cell-laden constructs with microscale filament size,whereas few studies have been devoted to developing bioinks that can be applied for EHD bioprinting and simultaneously support cell spreading.This study describes functionalized alginate-based bioinks for microscale EHD bioprinting using peptide grafting and fibrin incorporation,which leads to high cell viability(>90%)and cell spreading.The printed filaments can be further refined to as small as 30μm by incorporating polyoxyethylene and remained stable over one week when exposed to an aqueous environment.By utilizing the presented alginate-based bioinks,layer-specific cell alignment along the printing struts could be observed inside the EHD-printed microscale filaments,which allows fabricating living constructs with cell-scale filament resolution for guided cellular orientation. 展开更多
关键词 Microscale electrohydrodynamic bioprinting Alginate-based bioinks Cell spreading Cell alignment
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Topological phase transition in network spreading 被引量:1
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作者 年福忠 张霞 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期629-641,共13页
This paper investigates information spreading from the perspective of topological phase transition.Firstly,a new hybrid network is constructed based on the small-world networks and scale-free networks.Secondly,the att... This paper investigates information spreading from the perspective of topological phase transition.Firstly,a new hybrid network is constructed based on the small-world networks and scale-free networks.Secondly,the attention mechanism of online users in information spreading is studied from four aspects:social distance,individual influence,content richness,and individual activity,and a dynamic evolution model of connecting with spreading is designed.Eventually,numerical simulations are conducted in three types of networks to verify the validity of the proposed dynamic evolution model.The simulation results show that topological structure and node influence in different networks have undergone phase transition,which is consistent with the phenomenon that followers and individual influence in real social networks experience phase transition within a short period.The infection density of networks with the dynamic evolution rule changes faster and reaches higher values than that of networks without the dynamic evolution rule.Furthermore,the simulation results are compared with the real data,which shows that the infection density curve of the hybrid networks is closer to that of the real data than that of the small-world networks and scale-free networks,verifying the validity of the model proposed in this paper. 展开更多
关键词 social network information spreading network structure phase transition
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Human-centered Design for Green Landscape of Urban Streets
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作者 Yingchuan ZHAO Zhi LI 《Asian Agricultural Research》 2020年第11期49-52,58,共5页
This paper first introduces the development process of urban street green landscape in China and the human-centered thinking of the design of urban street green landscape.On the basis of detailed elaboration of the ba... This paper first introduces the development process of urban street green landscape in China and the human-centered thinking of the design of urban street green landscape.On the basis of detailed elaboration of the basic theories of urban street green landscape,it analyzes the existing problems and causes for urban street green landscape.Then,from the perspective of human-centered thought,it comes up with several measures for optimizing the green landscape design of urban streets,to provide much more human-centered experience of urban street green landscape. 展开更多
关键词 Urban streets Green landscape human-centered thought
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Boosting image watermarking authenticity spreading secrecy from counting-based secret-sharing 被引量:1
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作者 Adnan Gutub 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期440-452,共13页
This study presents enhancing images authentication by securing watermarking hidden data via shares generated from counting-based secret sharing.The trustfulness of shares utilised secret-sharing as an applicable priv... This study presents enhancing images authentication by securing watermarking hidden data via shares generated from counting-based secret sharing.The trustfulness of shares utilised secret-sharing as an applicable privacy creation tool for the authentication of real-life complex platforms.This research adjusts embedding the watermarking data over the images by innovative redistribution of shares to be embedded spread over all the images.The anticipated watermarking technique guaranteed to scatter the share bits implanting at different least significant bits of image pixels as boosting up the trust overall authentication practicality.The paper experimentation performance analysis shows that this improved image watermarking authentication(capacity)is averagely better by 33%–67%than other related exclusive-OR oriented and octagon approaches.Interestingly,these measurement improvements did not degrade the robustness and security of the system,inspiring our research for opening novel track of related future counting-based secret-sharing authentication progresses to come. 展开更多
关键词 counting-based secret-sharing data hiding fair data spreading image watermarking information security secret sharing
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Research on the Coordinated Development of Rural Revitalization and Human-centered Urbanization Based on Urban-rural Integration
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作者 Bo WANG Puming HE 《Asian Agricultural Research》 2021年第9期13-16,19,共5页
Although there are certain differences in the center of gravity between rural revitalization and human-centered urbanization,their connotations and goals require that both must be promoted in concert.Therefore,based o... Although there are certain differences in the center of gravity between rural revitalization and human-centered urbanization,their connotations and goals require that both must be promoted in concert.Therefore,based on a deep understanding of the connotation of rural revitalization and human-centered urbanization,it is necessary to clarify the goals of the two through the two-way flow of elements between urban and rural areas,the urban-rural linkage of industries,to achieve coordinated promotion of rural revitalization and human-centered urbanization in China. 展开更多
关键词 Urban-rural integration Rural revitalization human-centered urbanization
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Human-centered design of Stubble-Mulch Rotocultivator for Boat Tractor
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作者 Li Lin 《International Journal of Technology Management》 2014年第1期44-45,共2页
With the development of mechanization popularity in rural area, agricultural machinery product not only needs to meet the production goals, and also requires the simple operation and human-centered. Human-centered des... With the development of mechanization popularity in rural area, agricultural machinery product not only needs to meet the production goals, and also requires the simple operation and human-centered. Human-centered design is always, on the basis of the user' s requirement and usage, to think over the issues by regarding operator as the center, and to design the products by emphasizing the ease of use and understandability during design and manufacture. In this study, Stubble-Mulch Rotocultivator for Boat Tractor (SMRBT) is chosen as the design object. The coordination approach of the user, machine and environment is discussed by deeply investigating their relationship, which is an empirical study of the human-centered technology of agricultural machinery. 展开更多
关键词 Agricultural machinery products Stubble-Mulch Rotocultivator for Boat Tractor (SMRBT) human-centered design
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Nonpharmaceutical interventions eff ectively reduced infl uenza spread during the COVID-19 pandemic
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作者 Yuan Yuan Yan Li +4 位作者 Jiang-shan Wang Ye-cheng Liu Jun Xu Hua-dong Zhu Lu-zhao Feng 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第3期224-226,共3页
Seasonal infl uenza,which is transmitted by droplets and direct contact,is a global public health issue that causes an average of 2.5 excess infl uenza-like illness(ILI)consultations per 1,000 person-years in China.[1... Seasonal infl uenza,which is transmitted by droplets and direct contact,is a global public health issue that causes an average of 2.5 excess infl uenza-like illness(ILI)consultations per 1,000 person-years in China.[1]Nonpharmaceutical interventions(NPIs)against droplet and direct contact transmission,including social distancing measures and personal protective measures,are recommended to reduce the spread of disease.Social distancing measures comprised isolating ill persons,quarantining exposed persons,school and workplace closures,and avoiding crowds.Personal protective measures included hygiene,respiratory etiquette,and face masks.[2]In December 2019,coronavirus disease 2019(COVID-19)started to spread,and China introduced NPIs to address the pandemic in January 2020.These NPIs could also help reduce the spread of other respiratory diseases,such as seasonal influenza.[3]In the second half of 2020,the COVID-19 pandemic was gradually brought under control.Production,transport,and schools were returning to normal,while citizens were still required to wear masks in public.Cases of influenza also reappeared.This study compared the ILI percentage(ILI%),laboratory(LAB)-positive rate,incidence rate,and effective reproductive number(Rt)of infl uenzas from 2019 to 2022 to clarify the change in seasonal infl uenza spread after the COVID-19 outbreak. 展开更多
关键词 protective measures spread
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Simulation and Experimental Research on Liquid Spreading in a Wire-Sawn Kerf
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作者 Lin Lin Hui Huang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第6期247-260,共14页
The significance of liquids in abrasive wire sawing has been demonstrated in several studies.However,the perfor-mance of its spreading behavior is limited by the current development trend,where the wafer has a larger ... The significance of liquids in abrasive wire sawing has been demonstrated in several studies.However,the perfor-mance of its spreading behavior is limited by the current development trend,where the wafer has a larger area and the kerf is narrower.Moreover,there are very few studies on the liquid spreading behavior in wire-sawn kerfs.Therefore,a 3D CFD(computational fluid dynamics)model is presented in this paper and used to simulate the liquid spreading behavior in a kerf based on a VOF(volume of fluid)method with a CSF(continuum surface force)model,which is used to simulate multiphase flow,and an empirical correlation for characterizing the liquid dynamic contact angle using UDF(user defined functions).Subsequently,parametric simulations are performed on the kerf area,kerf width,liquid viscosity,liquid surface tension,and liquid velocity at the inlet area of the kerf,and verification experi-ments are conducted to determine the validity of the simulation model.From the simulation and experimental results,three typical liquid spreading regimes that exhibit different effects on wire sawing in the kerfs are found,and their limiting conditions are identified using non-dimensional analysis.Subsequently,a prediction model is pro-posed for the liquid spreading regime based on a set of Weber and Capillary numbers.For wire sawing,an increase in the wafer area does not change the liquid spreading regime in the kerf;however,a reduction in the kerf width sig-nificantly hinders the liquid spreading behavior.Thereby,the spreading regime can be effectively converted to facili-tate wire sawing by adjusting the physical properties and supply conditions of the liquid. 展开更多
关键词 spreading regime KERF CFD Non-dimensional analysis Prediction model
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BIFURCATION CONTROL FOR A FRACTIONAL-ORDER DELAYED SEIR RUMOR SPREADING MODEL WITH INCOMMENSURATE ORDERS
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作者 叶茂林 蒋海军 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2662-2682,共21页
A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation i... A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation is investigated by considering time delay as bifurcation parameter for the system without a feedback controller.Then,a state feedback controller is designed to control the occurrence of bifurcation in advance or to delay it by changing the parameters of the controller.Finally,in order to verify the theoretical results,some numerical simulations are given. 展开更多
关键词 rumor spreading FRACTIONAL-ORDER time delay bifurcation control
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Optical encryption scheme based on spread spectrum ghost imaging
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作者 刘进芬 董玥 +1 位作者 王乐 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期375-381,共7页
An optical encryption(OE) scheme based on the spread spectrum ghost imaging(SSGI), named as SSGI-OE, is proposed to obtain a high security with a smaller key. In the scheme, the randomly selected row number of a Hadam... An optical encryption(OE) scheme based on the spread spectrum ghost imaging(SSGI), named as SSGI-OE, is proposed to obtain a high security with a smaller key. In the scheme, the randomly selected row number of a Hadamard matrix of order N is used as the secure key, and shared with the authorized user, Bob, through a private channel. Each corresponding row vector of the order-N Hadamard matrix is then used as the direct sequence code to modulate a speckle pattern for the ghost imaging system, and an image is encrypted with the help of the SSGI. The measurement results from the bucket detector, named as ciphertext, are then transmitted to Bob through a public channel. The illuminating speckle patterns are also shared with Bob by the public channel. With the correct secure key, Bob could reconstruct the image with the aid of the SSGI system, whereas the unauthorized user, Eve, could not obtain any useful information of the encrypted image. The numerical simulations and experimental results show that the proposed scheme is feasible with a higher security and a smaller key. For the 32 × 32 pixels image, the number of bits sent from Alice to Bob by using SSGIOE(M = 1024, N = 2048) scheme is only 0.0107 times over a computational ghost imaging optical encryption scheme.When the eavesdropping ratio(ER) is less than 40%, the eavesdropper cannot acquire any information of the encrypted image. The extreme circumstance for the proposed SSGI-OE scheme is also discussed, where the eavesdropper begins to extract the information when ER is up to 15%. 展开更多
关键词 optical encryption ghost imaging spread spectrum correlated imaging
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