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Construction of a Computational Scheme for the Fuzzy HIV/AIDS Epidemic Model with a Nonlinear Saturated Incidence Rate 被引量:1
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作者 Muhammad Shoaib Arif Kamaleldin Abodayeh Yasir Nawaz 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1405-1425,共21页
This work aimed to construct an epidemic model with fuzzy parameters.Since the classical epidemic model doesnot elaborate on the successful interaction of susceptible and infective people,the constructed fuzzy epidemi... This work aimed to construct an epidemic model with fuzzy parameters.Since the classical epidemic model doesnot elaborate on the successful interaction of susceptible and infective people,the constructed fuzzy epidemicmodel discusses the more detailed versions of the interactions between infective and susceptible people.Thenext-generation matrix approach is employed to find the reproduction number of a deterministic model.Thesensitivity analysis and local stability analysis of the systemare also provided.For solving the fuzzy epidemic model,a numerical scheme is constructed which consists of three time levels.The numerical scheme has an advantage overthe existing forward Euler scheme for determining the conditions of getting the positive solution.The establishedscheme also has an advantage over existing non-standard finite difference methods in terms of order of accuracy.The stability of the scheme for the considered fuzzy model is also provided.From the plotted results,it can beobserved that susceptible people decay by rising interaction parameters. 展开更多
关键词 Epidemic model fuzzy rate parameters next generation matrix local stability proposed numerical scheme
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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching
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作者 Quanbo Ge Yang Cheng +3 位作者 Hong Li Ziyi Ye Yi Zhu Gang Yao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1424-1437,共14页
For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the... For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and symmetry.Some com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment. 展开更多
关键词 Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.
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A Neural-network-based Alternative Scheme to Include Nonhydrostatic Processes in an Atmospheric Dynamical Core
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作者 Yang XIA Bin WANG +13 位作者 Lijuan LI Li LIU Jianghao LI Li DONG Shiming XU Yiyuan LI Wenwen XIA Wenyu HUANG Juanjuan LIU Yong WANG Hongbo LIU Ye PU Yujun HE Kun XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1083-1099,I0002,I0003,共19页
Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostat... Here,a nonhydrostatic alternative scheme(NAS)is proposed for the grey zone where the nonhydrostatic impact on the atmosphere is evident but not large enough to justify the necessity to include an implicit nonhydrostatic solver in an atmospheric dynamical core.The NAS is designed to replace this solver,which can be incorporated into any hydrostatic models so that existing well-developed hydrostatic models can effectively serve for a longer time.Recent advances in machine learning(ML)provide a potential tool for capturing the main complicated nonlinear-nonhydrostatic relationship.In this study,an ML approach called a neural network(NN)was adopted to select leading input features and develop the NAS.The NNs were trained and evaluated with 12-day simulation results of dry baroclinic-wave tests by the Weather Research and Forecasting(WRF)model.The forward time difference of the nonhydrostatic tendency was used as the target variable,and the five selected features were the nonhydrostatic tendency at the last time step,and four hydrostatic variables at the current step including geopotential height,pressure in two different forms,and potential temperature,respectively.Finally,a practical NAS was developed with these features and trained layer by layer at a 20-km horizontal resolution,which can accurately reproduce the temporal variation and vertical distribution of the nonhydrostatic tendency.Corrected by the NN-based NAS,the improved hydrostatic solver at different horizontal resolutions can run stably for at least one month and effectively reduce most of the nonhydrostatic errors in terms of system bias,anomaly root-mean-square error,and the error of the wave spatial pattern,which proves the feasibility and superiority of this scheme. 展开更多
关键词 neural network nonhydrostatic alternative scheme atmospheric model dynamical core
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SIPS模型视域下电影短视频宣发策略探究
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作者 胡江伟 麦昊贤 《电影文学》 北大核心 2024年第6期75-79,共5页
随着短视频成为用户娱乐与社交的主要形式,电影宣发方也将其营销主阵地转至短视频平台,然而宣发实效与宣发方期待常相去甚远。如何提升短视频宣发与影片内容、用户期待的契合度,进而增强宣发实效,成为当前电影营销的核心关切。基于社交... 随着短视频成为用户娱乐与社交的主要形式,电影宣发方也将其营销主阵地转至短视频平台,然而宣发实效与宣发方期待常相去甚远。如何提升短视频宣发与影片内容、用户期待的契合度,进而增强宣发实效,成为当前电影营销的核心关切。基于社交媒体时代的SIPS模型研究发现,当前电影短视频宣发存在对用户观影期待感知不足、广宣内容模式化、宣发内容与购买转化相脱节、观众自传播效应尚未形成等问题,并提出以共情宣发满足观影期待、大数据决策锚定观影兴奋点、强关系连接促进购买转化、激活私域流量形成消费闭环的宣发策略。 展开更多
关键词 sips模型 短视频 共情 宣发
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Quantum-Resistant Multi-Feature Attribute-Based Proxy Re-Encryption Scheme for Cloud Services
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作者 Jinqiu Hou Changgen Peng +1 位作者 Weijie Tan Hongfa Ding 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期917-938,共22页
Cloud-based services have powerful storage functions and can provide accurate computation.However,the question of how to guarantee cloud-based services access control and achieve data sharing security has always been ... Cloud-based services have powerful storage functions and can provide accurate computation.However,the question of how to guarantee cloud-based services access control and achieve data sharing security has always been a research highlight.Although the attribute-based proxy re-encryption(ABPRE)schemes based on number theory can solve this problem,it is still difficult to resist quantum attacks and have limited expression capabilities.To address these issues,we present a novel linear secret sharing schemes(LSSS)matrix-based ABPRE scheme with the fine-grained policy on the lattice in the research.Additionally,to detect the activities of illegal proxies,homomorphic signature(HS)technology is introduced to realize the verifiability of re-encryption.Moreover,the non-interactivity,unidirectionality,proxy transparency,multi-use,and anti-quantum attack characteristics of our system are all advantageous.Besides,it can efficiently prevent the loss of processing power brought on by repetitive authorisation and can enable precise and safe data sharing in the cloud.Furthermore,under the standard model,the proposed learning with errors(LWE)-based scheme was proven to be IND-sCPA secure. 展开更多
关键词 LATTICE learning with errors attribute-based proxy re-encryption linear secret sharing schemes
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A Practical Regular LDPC Coded Scheme for Physical-Layer Information Security
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作者 Du Junyi 《China Communications》 SCIE CSCD 2024年第5期190-201,共12页
In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured L... In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured LDPC coded scheme,where the information bits in a codeword are punctured and only the parity check bits are transmitted to the receiver.We further propose a notion of check node type distribution and derive multi-edge type extrinsic information transfer functions to estimate the security performance,instead of the well-known weak metric bit error rate.We optimize the check node type distribution in terms of the signal-to-noise ratio(SNR)gap and modify the progressive edge growth algorithm to design finite-length codes.Numerical results show that our proposed scheme can achieve a lower computational complexity and a smaller security gap,compared to the existing scrambling and puncturing schemes. 展开更多
关键词 extrinsic information transfer function physical layer scheme secure open channel security gap
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Stability Analysis of Inverse Lax-Wendroff Procedure for a High order Compact Finite Difference Schemes
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作者 Tingting Li Jianfang Lu Pengde Wang 《Communications on Applied Mathematics and Computation》 EI 2024年第1期142-189,共48页
This paper considers the finite difference(FD)approximations of diffusion operators and the boundary treatments for different boundary conditions.The proposed schemes have the compact form and could achieve arbitrary ... This paper considers the finite difference(FD)approximations of diffusion operators and the boundary treatments for different boundary conditions.The proposed schemes have the compact form and could achieve arbitrary even order of accuracy.The main idea is to make use of the lower order compact schemes recursively,so as to obtain the high order compact schemes formally.Moreover,the schemes can be implemented efficiently by solving a series of tridiagonal systems recursively or the fast Fourier transform(FFT).With mathematical induction,the eigenvalues of the proposed differencing operators are shown to be bounded away from zero,which indicates the positive definiteness of the operators.To obtain numerical boundary conditions for the high order schemes,the simplified inverse Lax-Wendroff(SILW)procedure is adopted and the stability analysis is performed by the Godunov-Ryabenkii method and the eigenvalue spectrum visualization method.Various numerical experiments are provided to demonstrate the effectiveness and robustness of our algorithms. 展开更多
关键词 Compact scheme Diffusion operators Inverse Lax-Wendroff(ILW) Fourier analysis Eigenvalue analysis
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High Order IMEX Stochastic Galerkin Schemes for Linear Transport Equation with Random Inputs and Diffusive Scalings
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作者 Zheng Chen Lin Mu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期325-339,共15页
In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random inputs.To tackle the randomness in the problem,the stochastic Galerkin method of the g... In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random inputs.To tackle the randomness in the problem,the stochastic Galerkin method of the generalized polynomial chaos approach has been employed.Besides,the high order implicit-explicit scheme under the micro-macro decomposition framework and the discontinuous Galerkin method have been employed.We provide several numerical experiments to validate the accuracy and the stochastic asymptotic-preserving property. 展开更多
关键词 Stochastic Galerkin scheme linear transport equations generalized polynomial approach stochastic asymptotic-preserving property
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A New Double Layer Multi-Secret Sharing Scheme
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作者 Elavarasi Gunasekaran Vanitha Muthuraman 《China Communications》 SCIE CSCD 2024年第1期297-309,共13页
Cryptography is deemed to be the optimum strategy to secure the data privacy in which the data is encoded ahead of time before sharing it.Visual Secret Sharing(VSS)is an encryption method in which the secret message i... Cryptography is deemed to be the optimum strategy to secure the data privacy in which the data is encoded ahead of time before sharing it.Visual Secret Sharing(VSS)is an encryption method in which the secret message is split into at least two trivial images called’shares’to cover it.However,such message are always targeted by hackers or dishonest members who attempt to decrypt the message.This can be avoided by not uncovering the secret message without the universal share when it is presented and is typically taken care of,by the trusted party.Hence,in this paper,an optimal and secure double-layered secret image sharing scheme is proposed.The proposed share creation process contains two layers such as threshold-based secret sharing in the first layer and universal share based secret sharing in the second layer.In first layer,Genetic Algorithm(GA)is applied to find the optimal threshold value based on the randomness of the created shares.Then,in the second layer,a novel design of universal share-based secret share creation method is proposed.Finally,Opposition Whale Optimization Algorithm(OWOA)-based optimal key was generated for rectange block cipher to secure each share.This helped in producing high quality reconstruction images.The researcher achieved average experimental outcomes in terms of PSNR and MSE values equal to 55.154225 and 0.79365625 respectively.The average PSNRwas less(49.134475)and average MSE was high(1)in case of existing methods. 展开更多
关键词 genetic algorithm oppositional whale optimization algorithm rectangle block cipher secret sharing scheme SHARES universal share
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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River
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作者 LIU Xiao JIANG Xueyan +2 位作者 LIU Qian SUI Juanjuan ZOU Li 《Journal of Ocean University of China》 CAS CSCD 2024年第2期455-466,共12页
As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been c... As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment. 展开更多
关键词 chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties
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基于SIPS模型的短视频二次传播策略研究
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作者 华鲁辉 张智军 井媛 《传媒》 2024年第3期88-90,共3页
伴随着新媒体的崛起,信息的传播方式变得更加多元化。信息接收者与信息传递者之间的界限变得更为模糊,由共享与转发行为形成的二次传播也在信息传递中占据了重要地位。本文对二次传播形成的影响因素进行研究,在内容上首先对研究背景、... 伴随着新媒体的崛起,信息的传播方式变得更加多元化。信息接收者与信息传递者之间的界限变得更为模糊,由共享与转发行为形成的二次传播也在信息传递中占据了重要地位。本文对二次传播形成的影响因素进行研究,在内容上首先对研究背景、相关概念、二次传播对国内短视频发展的影响做了简要叙述,其次通过将SIPS模型带入广告视频的传播中,合理运用SIPS模型的传播特征、兴趣和共鸣的内在规律、双向沟通和及时性响应理论,为短视频的二次传播提供新的思路。 展开更多
关键词 sips模型 二次传播 短视频
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粉丝经济视角下乡村美食类短视频传播机理研究——基于SIPS模式的分析
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作者 王雪菲 《记者摇篮》 2024年第6期57-59,共3页
乡村振兴战略背景下的乡村美食类短视频打破了乡村信息的固有壁垒,农民群体通过高密度的媒介接触,进一步促进了农业农村的蓬勃发展。乡村美食类短视频获得受众青睐很大程度上依托于粉丝群体情感消费所带来的附加值,而乡村美食类短视频... 乡村振兴战略背景下的乡村美食类短视频打破了乡村信息的固有壁垒,农民群体通过高密度的媒介接触,进一步促进了农业农村的蓬勃发展。乡村美食类短视频获得受众青睐很大程度上依托于粉丝群体情感消费所带来的附加值,而乡村美食类短视频的创作与接收也极大等同于情感商品的生产与流通的过程。本文从粉丝经济的视角出发,基于SIPS模式分析乡村美食类短视频的传播机理。 展开更多
关键词 粉丝经济 乡村美食短视频 传播机理 sips模式
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Crank-Nicolson Quasi-Compact Scheme for the Nonlinear Two-Sided Spatial Fractional Advection-Diffusion Equations
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作者 Dechao Gao Zeshan Qiu +1 位作者 Lizan Wang Jianxin Li 《Journal of Applied Mathematics and Physics》 2024年第4期1089-1100,共12页
The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference oper... The higher-order numerical scheme of nonlinear advection-diffusion equations is studied in this article, where the space fractional derivatives are evaluated by using weighted and shifted Grünwald difference operators and combining the compact technique, in the time direction is discretized by the Crank-Nicolson method. Through the energy method, the stability and convergence of the numerical scheme in the sense of L<sub>2</sub>-norm are proved, and the convergence order is . Some examples are given to show that our numerical scheme is effective. 展开更多
关键词 Crank-Nicolson Quasi-Compact scheme Fractional Advection-Diffusion Equations NONLINEAR Stability and Convergence
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Sparse-Grid Implementation of Fixed-Point Fast Sweeping WENO Schemes for Eikonal Equations
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作者 Zachary M.Miksis Yong-Tao Zhang 《Communications on Applied Mathematics and Computation》 EI 2024年第1期3-29,共27页
Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of ... Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of fast sweeping schemes,fixed-point fast sweeping methods use the Gauss-Seidel iterations and alternating sweeping strategy to cover characteristics of hyperbolic PDEs in a certain direction simultaneously in each sweeping order.The resulting iterative schemes have a fast convergence rate to steady-state solutions.Moreover,an advantage of fixed-point fast sweeping methods over other types of fast sweeping methods is that they are explicit and do not involve the inverse operation of any nonlinear local system.Hence,they are robust and flexible,and have been combined with high-order accurate weighted essentially non-oscillatory(WENO)schemes to solve various hyperbolic PDEs in the literature.For multidimensional nonlinear problems,high-order fixed-point fast sweeping WENO methods still require quite a large amount of computational costs.In this technical note,we apply sparse-grid techniques,an effective approximation tool for multidimensional problems,to fixed-point fast sweeping WENO methods for reducing their computational costs.Here,we focus on fixed-point fast sweeping WENO schemes with third-order accuracy(Zhang et al.2006[41]),for solving Eikonal equations,an important class of static Hamilton-Jacobi(H-J)equations.Numerical experiments on solving multidimensional Eikonal equations and a more general static H-J equation are performed to show that the sparse-grid computations of the fixed-point fast sweeping WENO schemes achieve large savings of CPU times on refined meshes,and at the same time maintain comparable accuracy and resolution with those on corresponding regular single grids. 展开更多
关键词 Fixed-point fast sweeping methods Weighted essentially non-oscillatory(WENO)schemes Sparse grids Static Hamilton-Jacobi(H-J)equations Eikonal equations
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基于SIPS模型的图书馆短视频阅读推广策略研究
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作者 王瑞 《中文科技期刊数据库(文摘版)图书情报》 2024年第3期0202-0205,共4页
本文研究基于SIPS模型的图书馆短视频阅读推广策略。通过以SIPS模型为理论指导,本研究设计了与SIPS模型构成要素对应的图书馆短视频阅读推广创新思路。在激发情感认同方面,通过创造情感共鸣,激发读者参与活动的内生动力;在强化参与意愿... 本文研究基于SIPS模型的图书馆短视频阅读推广策略。通过以SIPS模型为理论指导,本研究设计了与SIPS模型构成要素对应的图书馆短视频阅读推广创新思路。在激发情感认同方面,通过创造情感共鸣,激发读者参与活动的内生动力;在强化参与意愿方面,调动读者常态化参与活动的积极性;在多维立体交互方面,打造图书馆与读者深度交互的阅读推广局面。通过本研究的创新策略,能够有效激发读者的情感共鸣、强化阅读意愿、参与阅读行为,进而推动图书馆短视频阅读推广的实践。 展开更多
关键词 sips模型 图书馆 短视频 阅读推广 创新策略
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Analysis and Comparison of Slope-cutting Widening Schemes in Highway Reconstruction and Expansion Project Based on MIDAS Software
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作者 Zhiqiang Qiu Yun Shi Lei Jiang 《Journal of Architectural Research and Development》 2024年第2期75-83,共9页
In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the m... In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the main contributor to the stability of the slope.Then,two widening schemes are proposed,which are the steep slope with strong support and the gentle slope with general support schemes.The static/slope module of MIDAS GTS finite element analysis software and the strength reduction method were used to compare the two schemes.The results show that the steep slope with a strong support scheme has obvious advantages in land requisition,environmental protection,and safety and is more suitable for reconstructing and expanding the highway slope. 展开更多
关键词 Highway reconstruction and expansion Slope excavation MIDAS GTS scheme selection
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基于SIPS模型的公共图书馆数字阅读推广实践路径研究 被引量:1
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作者 蒋露娟 《图书馆学刊》 2023年第3期69-74,共6页
以SIPS模型为研究工具,结合公共图书馆数字阅读推广活动探讨公共图书馆数字阅读推广活动实践路径:明确目标群体,精准定位品牌,激发目标群体共鸣;以用户画像为基点,精准策划推广内容;增设用户反馈渠道,培育和提升活动质量;建立用户激励机... 以SIPS模型为研究工具,结合公共图书馆数字阅读推广活动探讨公共图书馆数字阅读推广活动实践路径:明确目标群体,精准定位品牌,激发目标群体共鸣;以用户画像为基点,精准策划推广内容;增设用户反馈渠道,培育和提升活动质量;建立用户激励机制,以良好的口碑促使用户自觉扩散分享。 展开更多
关键词 sips模型 公共图书馆 数字阅读推广
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基于SIPS模型的全民健身借力短视频的推广策略
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作者 朱婷 周元超 《体育科技文献通报》 2023年第4期92-94,265,共4页
现阶段是互联网高速发展的时代,健身类短视频层出不穷,逐渐呈现出新型健身传播路径。本文以sips模型为理论依据,从其共鸣·确认·参与·分享四个维度对利用短视频推广全民健身进行价值判断,分析健身短视频的传播现状,提出... 现阶段是互联网高速发展的时代,健身类短视频层出不穷,逐渐呈现出新型健身传播路径。本文以sips模型为理论依据,从其共鸣·确认·参与·分享四个维度对利用短视频推广全民健身进行价值判断,分析健身短视频的传播现状,提出使用短视频推广全民健身的优化策略,旨在助力全民健身运动的高质量发展。 展开更多
关键词 短视频 sips模型 全民健身
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基于SIPS模型的省级文旅政务短视频优化策略
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作者 辛海滨 王晓倩 《新闻世界》 2023年第11期61-64,共4页
短视频平台是文旅资源宣传推广的重要途径,各级文旅部门通过短视频媒介输出地域文化和旅游产品,优化区域旅游形象和传播策略。本研究以省级文旅政务抖音号为研究对象,采用描述统计、相关分析和文本主题聚类等方法,梳理当前文旅政务短视... 短视频平台是文旅资源宣传推广的重要途径,各级文旅部门通过短视频媒介输出地域文化和旅游产品,优化区域旅游形象和传播策略。本研究以省级文旅政务抖音号为研究对象,采用描述统计、相关分析和文本主题聚类等方法,梳理当前文旅政务短视频传播的形式特征、内容特征和存在的突出问题,并进一步基于SIPS模型从共鸣、确认、参与、共享和扩散四个维度提出优化策略,以期为文旅事业发展提供有益参考。 展开更多
关键词 短视频 文旅政务 sips模型 优化策略
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NiMoO_(4)/ZnIn_(2)S_(4)S-scheme异质结的制备及光催化产氢性能增强机制 被引量:5
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作者 李艳 李卓 刘恩周 《聊城大学学报(自然科学版)》 2023年第2期1-10,共10页
首先通过水热法制备得到NiMoO_(4)·x H_(2)O前驱体,再经高温煅烧得到NiMoO_(4)纳米棒,最后通过超声混合及溶剂蒸干处理将NiMoO_(4)与ZnIn_(2)S_(4)复合构建了NiMoO_(4)/ZnIn_(2)S_(4)S-scheme异质结光催化剂。研究结果表明,NiMoO_... 首先通过水热法制备得到NiMoO_(4)·x H_(2)O前驱体,再经高温煅烧得到NiMoO_(4)纳米棒,最后通过超声混合及溶剂蒸干处理将NiMoO_(4)与ZnIn_(2)S_(4)复合构建了NiMoO_(4)/ZnIn_(2)S_(4)S-scheme异质结光催化剂。研究结果表明,NiMoO_(4)质量分数为10.7%时,复合材料(10.7-NiMoO_(4)/ZnIn_(2)S_(4))具有较好的载流子分离效率,较低的界面电荷转移阻力和较大的电化学活性面积。在300 W氙灯照射下,其产氢速率可达29.04 mmol·g^(-1)·h^(-1),约为单体ZnIn_(2)S_(4)(5.58 mmol·g^(-1)·h^(-1))的5.20倍。自由基捕获实验及能带结构分析表明,NiMoO_(4)和ZnIn_(2)S_(4)之间形成了S-scheme电荷转移机制,不仅促进了载流子的分离与迁移,而且保留了较强的氧化还原能力。此外,NiMoO_(4)的引入提高了异质结的电化学活性面积,以上因素协同提高了体系的光催化析氢性能。 展开更多
关键词 NiMoO_(4) ZnIn_(2)S_(4) S-scheme异质结 光催化产氢
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