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基于PSO-BP神经网络的硅基光子器件光损耗异常监测系统
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作者 闵月淇 谢亮 《现代电子技术》 北大核心 2026年第2期49-53,共5页
硅基光子器件的光损耗易受多种运行参数影响,导致其光损耗异常监测存在偏差或遗漏。为全面考虑多种运行参数的影响,实现对其光损耗异常的全面精准监测,设计一种基于PSO-BP神经网络的硅基光子器件光损耗异常监测系统。采用系统的数据采... 硅基光子器件的光损耗易受多种运行参数影响,导致其光损耗异常监测存在偏差或遗漏。为全面考虑多种运行参数的影响,实现对其光损耗异常的全面精准监测,设计一种基于PSO-BP神经网络的硅基光子器件光损耗异常监测系统。采用系统的数据采集模块实时采集硅基光子器件的波长、温度等运行参数,再通过数据预处理模块对各参数进行处理,并输入以PSO-BP神经网络为核心的光损耗检测模块,从而获得各种运行参数下的光损耗检测值。异常监测预警模块将所得光损耗检测值与设定阈值进行对比,判断光损耗是否异常,若异常则发出预警。用户交互模块呈现异常监测及预警信息,完成硅基光子器件光损耗异常监测。结果表明,所设计系统可针对不同波长、温度、波导长度及输出光功率等运行参数,实现对硅基光子器件光损耗异常的全面监测,并对各种异常光损耗场景进行有效预警。 展开更多
关键词 硅基光子器件 光损耗 异常监测 pso-bp神经网络 异常预警 波导长度
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基于PSO-BP神经网络的热电厂负荷预测策略研究
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作者 胡旭 米欣 曹琦 《科技创新与应用》 2026年第1期32-35,共4页
目前能源的高效利用和绿色发展受到学者们广泛的关注。该文针对某热电厂能源管理系统产生的大量历史数据,采用大数据分析的方法计算出数据之间的关联系数,以判断数据间的关联状况。建立PSO-BP神经网络模型对某热电厂未来24 h的热负荷进... 目前能源的高效利用和绿色发展受到学者们广泛的关注。该文针对某热电厂能源管理系统产生的大量历史数据,采用大数据分析的方法计算出数据之间的关联系数,以判断数据间的关联状况。建立PSO-BP神经网络模型对某热电厂未来24 h的热负荷进行预测,以便为热电厂更好地提供生产、运营、管理决策服务等。PSO-BP神经网络模型是将粒子群算法与BP算法融合产生的,不仅能够提高BP神经网络的预测精度,而且可以有效地解决BP神经网络算法学习速度慢及易陷入局部极小值、稳定性差等问题。 展开更多
关键词 大数据分析 用热特性 预测模型 pso-bp神经网络 预测精度
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基于PSO-BP神经网络的既有桩基极限承载力预测研究
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作者 郝彬 田增顺 +2 位作者 马卫建 姜勇 赵素菊 《山东农业大学学报(自然科学版)》 北大核心 2026年第1期189-198,共10页
针对既有桩基再利用中极限承载力评估困难的问题,本文通过13根既有桩基现场静载试验与数值模拟方法,对既有桩基极限承载力展开了分析。在此基础上,基于230组数据样本,采用BP、PSO-BP神经网络对单桩极限承载力进行预测,并通过决定系数(R^... 针对既有桩基再利用中极限承载力评估困难的问题,本文通过13根既有桩基现场静载试验与数值模拟方法,对既有桩基极限承载力展开了分析。在此基础上,基于230组数据样本,采用BP、PSO-BP神经网络对单桩极限承载力进行预测,并通过决定系数(R^(2))、均方根误差(MAE)和平均绝对误差(RMSE)三个指标评价了预测结果。研究结果表明:9根破坏性试验桩的极限承载力均为桩基再利用设计值的2~3倍,安全储备较为充足。4根非破坏性试验桩回弹率均超过80%,结合数值模拟确定了其单桩极限承载力均大于桩基再利用设计值,验证了其再利用的可行性。预测模型对比分析,PSO-BP模型的决定系数较传统BP模型提升了196%,平均绝对误差与均方根误差分别降低了66%和62%,预测误差多控制在±2000 kN以内。研究成果为既有桩基承载力高效评估与再利用提供了科学依据。 展开更多
关键词 既有桩基 极限承载力 承载力预测 pso-bp神经网络
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基于PSO-BP神经网络矿井涌水量预测模型
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作者 李启兴 张宇 +1 位作者 乔秀杰 闫国成 《煤》 2026年第1期94-99,共6页
矿井涌水量的准确预测对矿山建设及煤层安全高效回采意义重大。文章以某华北型煤田煤矿为研究对象,该矿主要受石炭-二叠系砂岩裂隙含水层影响。研究采用时间序列分析方法、BP和PSO-BP神经网络模型构建多模型预测体系。通过聚类分析发现... 矿井涌水量的准确预测对矿山建设及煤层安全高效回采意义重大。文章以某华北型煤田煤矿为研究对象,该矿主要受石炭-二叠系砂岩裂隙含水层影响。研究采用时间序列分析方法、BP和PSO-BP神经网络模型构建多模型预测体系。通过聚类分析发现,该矿涌水量受季节性影响小,进而将其视为整体研究。时间序列模型预测结果表明,该模型有一定预测能力,但存在弊端。引入PSO-BP方法优化模型,对比BP神经网络等模型,结果显示PSO-BP神经网络预测模型准确性最高(R^(2)=0.9924,RMSE值为0.08219),为矿井涌水量精准预测、灾害预警及煤矿安全生产提供了有效方法和理论支撑。 展开更多
关键词 涌水量预测 时间序列模型 pso-bp
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基于PSO-BP算法的平-摆筛参数交互对分层效果的影响
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作者 牛福生 张红梅 +2 位作者 张晋霞 王研 于晓东 《矿产综合利用》 2026年第1期151-160,共10页
以平-摆双运行模式直线振动筛参数:振幅、振频、振动方向角和摆动角度为研究对象,探究不同参数交互作用对分层效果的影响。【目的】为更加直观地分析振动筛的筛分参数与分层效果的复杂影响关系以及筛分过程中料体群的动态特性规律,便于... 以平-摆双运行模式直线振动筛参数:振幅、振频、振动方向角和摆动角度为研究对象,探究不同参数交互作用对分层效果的影响。【目的】为更加直观地分析振动筛的筛分参数与分层效果的复杂影响关系以及筛分过程中料体群的动态特性规律,便于开展振动筛参数优化研究,提升料体筛分分层效果及筛分效率。【方法】首先使用solid works建立振动筛简化三维模型,使用正交实验法设计实验方案,并将实验方案中对应因素水平导入EDEM中,以神经网络为载体探究振动筛的振幅、振动频率、振动方向角和摆动角度四个参数与分层效果的变化规律,对获得的数据结果进行深度学习。【结果】将筛分参数与不同分层效果进行影响权重分析,发现振动频率、振动幅度、振动方向角和摆动角度的影响效果最为显著,故以这四种参数组合表征振动筛运行状态,以明晰不同参数对料体分层效果的变化规律。当振幅为3.4 mm,振频为14.8 Hz,振动方向角为44.1°,摆动角度为0.6°时,料体群分层效果明显,细粒级物料总体分布于筛面端。【结论】本文以筛机振动参数为变量和料体分层效果为优化目标,以期为振动筛优化设计提供启发。 展开更多
关键词 振动筛 振动参数 离散元 分层沉降比 pso-bp算法
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Study on the effect of preparation method on denitration performance of Co-modified Ce/TiO_(2) catalyst
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作者 YU Chao ZHANG Boya +2 位作者 SHEN Kai HAN Yuxuan ZHANG Yaping 《燃料化学学报(中英文)》 北大核心 2026年第3期79-91,共13页
This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s... This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s low-temperature denitrification activity.After identifying optimal preparation parameters via condition screening,multiple characterization techniques-including BET,XRD,XPS,H_(2)-TPR and in situ DRIFTS-were employed to deeply analyze the catalyst’s physicochemical properties and reaction mechanism.Results demonstrated that compared to the impregnation and co-precipitation methods,the Ce-Co_(0.025)/TiO_(2)-SG catalyst(prepared by the sol-gel method with a Co/Ti mass ratio of 0.025)exhibited significantly superior denitrification activity:NO conversion remained stably above 95%in the 225−350℃ temperature range,and it displayed high N_(2) selectivity.Characterization analysis revealed that abundant surface oxygen vacancies,a high proportion of Ce^(3+) species,and prominent acidic sites collectively contributed to enhancing its low-temperature denitrification performance.This work provides reference value for the development of highly efficient low-temperature denitrification catalysts. 展开更多
关键词 preparation method Co Ce/TiO_(2) low-temperature denitration NH3-SCR
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Broadband ground motion simulation and analysis of a near-fault 3D basin-mountain coupling site based on the hybrid method
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作者 Liu Zhongxian Tang Kang +2 位作者 Li Chengcheng Yuan Xiaoming Zhang Hai 《Earthquake Engineering and Engineering Vibration》 2026年第1期87-110,共24页
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE... This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions. 展开更多
关键词 hybrid ground motion simulation method spectral element method three-dimensional stochastic finite fault method near-fault basin-mountain coupling effect basin effect nonlinear effect
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Establishment of a Determination Method for Fruit Texture in Chieh-qua Using Texture Analyzer
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作者 Ying WANG Xuan DU Na LIU 《Agricultural Biotechnology》 2026年第1期54-59,共6页
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun... [Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua. 展开更多
关键词 CHIEH-QUA Texture analyzer Texture quality Determination method
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A novel scaling method for the elastic ring supporting structure of an aero-engine rotor system: analytical and experimental investigations
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作者 Lei LI Tianyue MA +4 位作者 Zhong LUO Dongwu GAO Xiangdong GE Hui MA Shibin WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期1-18,共18页
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr... The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings. 展开更多
关键词 rotor system AERO-ENGINE elastic ring scaling method supporting structure
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Multiphysics Implicit Coupling Method for Fluid,Particles,and Large-Deformation Structures
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作者 Xiangxiang Wang Hualong Xie +3 位作者 Yue Yu Min Li Yubin Wang Fei Xing 《Computer Modeling in Engineering & Sciences》 2026年第2期367-401,共35页
This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,Calcu... This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,CalculiX,and preCICE to simulate fluid-particle-structure interactions with large deformations.Mesh motion in the fluid field is handled using the radial basis function(RBF)method.The particle phase is modeled by MPPIC,where fluid-particle interaction is described through momentum exchange,and inter-particle collisions are characterized by collision stress.The structural field is solved by nonlinear FEM to capture large deformations induced by geometric nonlinearity.Coupling among fields is realized through a partitioned,parallel,and non-intrusive iterative strategy,ensuring stable transfer and convergence of interface forces and displacements.Notably,the influence of particles on the structure is not direct but mediated by the fluid,while structural motion directly affects particle dynamics.The results demonstrate that the proposed approach effectively captures multiphysics interaction processes and provides a valuable reference for numerical modeling of coupled fluid-particle-structure systems. 展开更多
关键词 Fluid-particle-structure interaction large deformation partitioned method non-intrusive coupling
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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Investigation of equivalent strength parameters of soil-rock mixture using numerical manifold method
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作者 Junfeng Li Yongtao Yang +2 位作者 Yang Xia Hong Zheng Shuilin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期637-650,共14页
As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalen... As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalent parameters of SRMs,which are typically obtained through experimental and numerical methods.In contrasted to other numerical methods,the numerical manifold method(NMM)is more effective in addressing SRM problems.This is because the high-precision regular mathematical meshes in NMM can be used without aligning with the soil-rock interfaces and boundaries of SRMs.In the current research,the equivalent strength parameters of SRMs,i.e.the equivalent cohesion ce and internal friction angleϕ_(e),are determined using NMM.Initially,an NMM triaxial numerical model is established and validated based on triaxial experiments.Subsequently,the soil and rock parameters are derived through parameter inversion.Moreover,the impacts of rock content,size,shape and rock blocks'major-axis orientation on ce andϕ_(e) of SRMs are thoroughly examined using the NMM triaxial numerical model.Additionally,a fitting function is proposed to linkϕ_(e) to the rock content and size of SRMs.When other influencing factors are fixed,the above fitting model leads to the following conclusions:(1)the predictedϕ_(e) of SRMs increase with the increase of rock content;and(2)SRM samples with smaller rocks display a higher predictedϕ_(e). 展开更多
关键词 Soil-rock mixtures Equivalent strength parameters Numerical manifold method
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Subtitle Translation Methods of The Good Wife From Functional Equivalence Perspective
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作者 WANG Ya-kun BAO De-wang 《Journal of Literature and Art Studies》 2026年第1期26-30,共5页
The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to... The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to analyze the methods of its English-to-Chinese subtitle translation by considering social,cultural,and historic backgrounds between China and America.After data collection and case analysis,the study found that:(1)Five major translation methods are adopted in the subtitle translation of The Good Wife.They are free translation,variation,literal translation,addition,and omission.Among them,free translation is the most frequently used,while omission is used least.(2)The subtitle translation of films and TV series is limited by time and space restrictions,social-cultural differences,and other factors.When translating,translators should try to use humorous words,euphemism,intonation,and other ways,and combine different methods such as literal translation,free translation,variation,addition,omission,and other methods to seek equivalence both in the meaning and function of subtitles under the guidance of Functional Equivalence Theory. 展开更多
关键词 subtitle translation Functional Equivalence Theory The Good Wife translation methods
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Pile installation effects in natural soft clays:A semi-analytical solution using strain path method
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作者 Liang Li Pan Zhou +3 位作者 Jingpei Li Seyedmohsen Miraei Peng Feng Mingdong Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期728-744,共17页
This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture ... This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture the anisotropic evolution and destructuring nature of soft clays.By integrating the S-CLAY1S model into the theoretical framework of the SPM,a set of ordinary differential equations is formulated with respect to the vertical coordinate of soil particles.The distribution of excess pore water pressure(EPWP)following pile installation is approximated through one-dimensional(1D)radial integration around the pile shaft.The distribution of stresses and EPWP,along with the evolution of fabric anisotropy within the soil surrounding the pile,is presented to illustrate the response of pile penetration in natural soft clays.The proposed solution is validated against existing theoretical solutions using the SPM and cavity expansion method(CEM),along with experimental data.The findings demonstrate that the SPM reveals lower radial effective stresses and EPWP at the pile shaft than that of CEM.Pile penetration alters the soil's anisotropic properties,inducing rotational hardening and affecting post-installation stress distribution.Soil destructuration eliminates bonding among particles near the pile,resulting in a complete disruption of soil structure at the pile surface,which is particularly pronounced for higher initial soil structure ratios.Minimal variation was observed in the three principal stresses and shear stress on the cone side surface as the angle increased from 18°to 60°,except for a slight reduction in EPWP. 展开更多
关键词 Pile penetration Strain path method Natural soft clays Anisotropy evolution Destructuration
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Crushing evolution in pebble bed based on a novel method:a crushable DEM study
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作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
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Correction models of Reynolds number effects for through-flow method in axial compressors
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作者 Xiaochen WANG Chunwei GU 《Chinese Journal of Aeronautics》 2026年第1期78-94,共17页
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha... Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors. 展开更多
关键词 Axial compressor Reynolds number effects Correction model Through-flow method Aerodynamic performance
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ANALYSIS OF A QUADRILATERAL EDGE ELEMENT METHOD FOR MAXWELL EQUATIONS
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作者 Zhijie DU Huoyuan DUAN Caihong WANG 《Acta Mathematica Scientia》 2026年第1期275-292,共18页
A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue prob... A new quadrilateral edge element method is proposed and analyzed for Maxwell equations.This proposed method is based on Duan-Liang quadrilateral element(Math.Comp.73(2004),pp.1–18).When applied to the eigenvalue problem,the method is spectral-correct and spurious-free.Stability and error estimates are obtained,including the interpolation error estimates and the error estimates between the finite element solution and the exact solution.The method is suitable for singular solution as well as smooth solution,and consequently,the method is valid for nonconvex domains which may have a number of reentrant corners.Of course,the method is suitable for arbitrary quadrilaterals(under the usual shape-regular condition). 展开更多
关键词 Maxwell equations finite element method quadrilateral mesh STABILITY error bound spectral approximation
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A Deep Reinforcement Learning-Based Partitioning Method for Power System Parallel Restoration
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作者 Changcheng Li Weimeng Chang +1 位作者 Dahai Zhang Jinghan He 《Energy Engineering》 2026年第1期243-264,共22页
Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision... Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training. 展开更多
关键词 Partitioning method parallel restoration deep reinforcement learning experience replay buffer partitioning modularity
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