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Phase Transformation on Chemically Corroded Surface of a Single-Crystal Superalloy During In-Situ Tension at Elevated Temperatures
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作者 Wang Rui Li Jiarong +2 位作者 Yue Xiaodai Zhao Jinqian Yang Wanpeng 《稀有金属材料与工程》 北大核心 2026年第3期595-601,共7页
In-situ tensile tests were conducted on a chemically corroded third-generation single-crystal superalloy DD9 at 980 and 1100℃.The phase transformation in the surface areas during the tensile process was analyzed usin... In-situ tensile tests were conducted on a chemically corroded third-generation single-crystal superalloy DD9 at 980 and 1100℃.The phase transformation in the surface areas during the tensile process was analyzed using field emission scanning electron microscope,energy dispersive X-ray spectroscope,electron probe X-ray microanalysis,and transmission electron microscope.The phase transformation mechanism on the surface and the influence mechanism were studied through observation and dynamic calculation.During tensile tests at elevated temperatures,chemical corrosion promotes the precipitation of topologically close-packed(tcp)μphase andσphase on the alloy surface.Both the precipitation amount and size of these two phases on the surface at 1100℃are greater than those at 980℃.The precipitation of tcp phase on the alloy surface results in the formation of an influence layer on the surface area,and the distribution characteristics of alloying elements are significantly different from those of the substrate.The depth of the influence layer at 1100℃is greater than that at 980℃.The precipitation of tcp phase prompts the phase transition fromγphase toγ′phase around the tcp phase. 展开更多
关键词 single-crystal superalloy in-situ tension tcp phase phase transformation alloying element
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Prediction of ferrite transformation start temperature in hot-rolled aluminum bearing dual-phase steel based on combination of metallurgical principles and experimental data
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作者 Xiao-Guang Zhou Si-Qiao Wang +5 位作者 Xu-Yuan Zhang Hong-Bing Wang Chun-Yang Shu Xin-Yao Zhang Si-Wei Wu Zhen-Yu Liu 《Journal of Iron and Steel Research International》 2026年第1期149-158,共10页
The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The me... The accurate establishment of a ferrite transformation start temperature model is crucial to design a reasonable controlled rolling process and ensure uniform microstructure in aluminum bearing dual-phase steel.The measurements of the expansion-temperature curves of aluminum bearing dual-phase steel under continuous cooling and isothermal conditions are presented,utilizing a dynamic transformation dilatometer experiment.Based on these expansion-temperature curves,the start temperature and incubation time of ferrite transformation were determined,elucidating the influence of process parameters on both the incubation time and the start temperature of ferrite transformation.By integrating metallurgical principles with measured incubation time of ferrite transformation,and considering the effects of temperature and strain,a fitting model for the variation in volume free energy during ferrite nucleation was derived.Building upon this foundation,a high-precision incubation time of ferrite transformation mathematical model for the experimental steel was established.To more accurately calculate the start temperature of ferrite transformation under continuous cooling conditions,the Scheil’s additivity rule was modified to account for the effects of deformation and cooling rate.The results indicate that the modification coefficient decreases with increasing the cooling rate and strain,thereby significantly improving the accuracy of calculating the starting temperature of ferrite transformation using the modified additivity rule. 展开更多
关键词 Dual-phase steel Ferrite transformation Incubation time Ferrite transformation start temperature Model
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Sequential phase transformations in Ta_(0.4)Ti_(2)Zr alloy via tensile molecular dynamics simulations with deep potential
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作者 Hongyang Liu Rong Chen +3 位作者 Bo Chen Jingzhi He Dongdong Kang Jiayu Dai 《Chinese Physics B》 2026年第1期46-55,共10页
Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular ... Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular dynamics simulations of the Ta_(0.4)Ti_(2)Zr(Ta_(0.4))alloy.Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta_(0.4)alloy.Under uniaxial tensile loading along the[100]direction in the NPT ensemble,the alloy undergoes a remarkable sequence of phase transformations:an initial body-centered cubic(BCC_(1))to face-centered cubic(FCC)transformation,followed by a reverse transformation from FCC to a distinct BCC phase(BCC_(2)),and finally a BCC_(2) to hexagonal close-packed(HCP)transformation.Critically,the reverse FCC to BCC_(2) transformation induces significant volume contraction.We demonstrate that the inversely transformed BCC_(2) phase primarily accommodates compressive stress.Concurrently,the reorientation of BCC_(2) crystals contributes substantially to the observed high strain hardening.These simulations provide atomic-scale insights into the dynamic structural evolution,sequential phase transformations,and stress partitioning during deformation of the Ta_(0.4)alloy.The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs. 展开更多
关键词 multi-principal element alloys machine-learning potential phase transformation stress partitioning
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Effect of fluoride roasting on copper species transformation on chrysocolla surfaces and its role in enhanced sulfidation flotation
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作者 Yingqiang Ma Xin Huang +5 位作者 Yafeng Fu Zhenguo Song Sen Luo Shuanglin Zheng Feng Rao Wanzhong Yin 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期165-176,共12页
It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla we... It is difficult to recover chrysocolla from sulfidation flotation which is closely related to the mineral surface composition.In this study,the effects of fluoride roasting on the surface composition of chrysocolla were investigated,its impact on sulfidation flotation was explored,and the mechanisms involved in both fluoride roasting and sulfidation flotation were discussed.With CaF_(2)as the roasting reagent,Na_(2)S·9H_(2)O as the sulfidation reagent,and sodium butyl xanthate(NaBX)as the collector,the results of the flotation experiments showed that fluoride roasting improved the floatability of chrysocolla,and the recovery rate increased from 16.87%to 82.74%.X-ray diffraction analysis revealed that after fluoride roasting,approximately all the Cu on the chrysocolla surface was exposed in the form of CuO,which could provide a basis for subsequent sulfidation flotation.The microscopy and elemental analyses revealed that large quantities of"pagoda-like"grains were observed on the sulfidation surface of the fluoride-roasted chrysocolla,indicating high crystallinity particles of copper sulfide.This suggests that the effect of sulfide formation on the chrysocolla surface was more pronounced.X-ray photoelectron spectroscopy revealed that fluoride roasting increased the relative contents of sulfur and copper on the surface and that both the Cu~+and polysulfide fractions on the surface of the minerals increased.This enhances the effect of sulfidation,which is conducive to flotation recovery.Therefore,fluoride roasting improved the effect of copper species transformation and sulfidation on the surface of chysocolla,promoted the adsorption of collectors,and improved the recovery of chrysocolla from sulfidation flotation. 展开更多
关键词 sulfidation flotation CHRYSOCOLLA fluoride roasting copper species transformation enhanced sulfidation
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Efficient genetic transformation and gene editing in Erigeron breviscapus using developmental regulators
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作者 Qin Zhu Yingchun Lu +8 位作者 Yunhui Yang Jiayao Song Rong Gong Shanglin Zhang Jinglei Xiong Shengchao Yang Guanghui Zhang Jianli Yang Simei He 《The Crop Journal》 2026年第1期296-301,共6页
The demand for Erigeron breviscapus,a medicinal Compositae plant with cardiovascular therapeutic properties,has been increasing by 15%annually,exceeding production capacity and necessitating improvements in yield and ... The demand for Erigeron breviscapus,a medicinal Compositae plant with cardiovascular therapeutic properties,has been increasing by 15%annually,exceeding production capacity and necessitating improvements in yield and bioactive compound content.Genetic transformation remains essential for functional genomics,yet current Agrobacterium and biolistic methods are inefficient and expensive.In this study,we cloned the full-length sequences of the BABY BOOM,WUSCHEL and GROWTH-REGULATING FACTOR(GRF)genes of E.breviscapus and then transformed them into E.breviscapus explants.The transformation efficiency for the GRF gene reached 45%,and all the transgenic E.breviscapus plants were fertile without obvious developmental defects.Furthermore,we inserted EbGRF4 and Cas9-EbPDS-sgRNA into the same vector for Agrobacterium-mediated transformation to effectively knock out the PDS gene,resulting in albino seedlings,with a gene editing efficiency of 33.3%.These findings provide a solid foundation for functional genomic research and the genetic improvement of E.breviscapus,as well as an important reference for establishing high-efficiency genetic transformation systems for other medicinal plants. 展开更多
关键词 Developmental regulators Erigeron breviscapus Genetic transformation Genome editing Technical advance
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Current status of the genetic transformation of Arachis plants
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作者 Hui Song Meiran Li Zhenquan Duan 《Journal of Integrative Agriculture》 2026年第2期577-584,共8页
Peanuts(Arachis hypogaea) are important sources of vegetable oil,protein,and forage.The genus Arachis comprises nine intrageneric taxonomic sections encompassing 84 species.Most Arachis species are wild plants that se... Peanuts(Arachis hypogaea) are important sources of vegetable oil,protein,and forage.The genus Arachis comprises nine intrageneric taxonomic sections encompassing 84 species.Most Arachis species are wild plants that serve widely as forage and turfgrass.Furthermore,wild Arachis species provide valuable gene resources for broadening the genetic diversity of cultivated peanuts.To date,several key genes have been identified through the use of recombinant inbred lines derived from interspecific crosses within Arachis.Despite this progress,the application of genetic engineering to enhance peanut traits remains limited.This limitation arises primarily from the absence of a robust and reliable genetic transformation protocol for Arachis species.Nevertheless,evidence indicates that successful genetic transformation of Arachis plants was first reported approximately 30 years ago.Thus,a notable discrepancy exists between early reports of transformation success and the ongoing challenges in stably transferring candidate genes into Arachis genotypes.This review summarizes existing methods for regeneration and genetic transformation in Arachis,aiming to advance understanding of transgenic technologies applicable to this genus. 展开更多
关键词 ARACHIS CRISPR/Cas9 genetic transformation in vitro regeneration
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum TECHNOLOGY industrial strength high tech transition guangdong manufacturing transformation
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A numerical model for cascading glacier mass flow analysis(GMFA):Erosion-deposition dynamics,phase changes,and multi-hazard chain transformations
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作者 Ruochen Jiang Limin Zhang +4 位作者 Wenjun Lu Dalei Peng Xin He Shihao Xiao Mingdong Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期299-316,共18页
Glacier landslide cascading hazards pose threats to communities and infrastructure,affected by complex processes including the amplification of mass flow volume through erosion and entrainment,transformation of hazard... Glacier landslide cascading hazards pose threats to communities and infrastructure,affected by complex processes including the amplification of mass flow volume through erosion and entrainment,transformation of hazard types,ice-water phase change,and enhanced mobility of the mass flow.Scientifically simulating these physical phenomena proves challenging.This study introduces GMFA(glacier mass flow analysis),an integrated numerical model that advances the field by:(1)proposing depth-averaged fluctuation energy and internal energy equations,(2)incorporating the ice-water phase change and the entrainment-deposition process,and(3)capturing their effects on mass flow runout characteristics.The model employs the finite volume method to solve the multi-physics coupled governing equations,enabling efficient large-scale simulations.The model is verified through three numerical tests covering flow dynamics,temperature evolution,and thermo-hydro-mechanical runout processes.The model is applied to analyze a hazard chain that occurred on 10 September 2020 on the Tibetan Plateau.The multi-scenario simulation results indicate an entrained mass volume of(4.95±0.11)×10^(5)m^(3),and a ratio of entrained mass volume to source material volume of 0.44.The solid concentration decreases from 0.6-0.7 to 0.1-0.15 with increasing runout distance,indicating a transition from avalanche to debris flood.The internal energy rises by(3-4)×10^(3)kJ/m^(3),driving rapid ice melting from 0.1 to 0.2 to near-zero concentration.The model effectively quantifies volume amplification,ice-water phase changes,and multi-hazard transformations.This model pushes the geoscience frontier,extending computational capability from single-to multi-hazard simulations and providing a powerful tool for analyzing glacier cascading hazards. 展开更多
关键词 Glacier hazard chains LANDSLIDES Debris flows Phase change Erosion and deposition Hazard transformation
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The Transformation,Challenges and Path Reconstruction of Interaction Between Teachers and Students in Higher Education Institutions in the Era of Intelligent Media
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作者 ZHANG Zhanjun 《Cultural and Religious Studies》 2026年第1期43-46,共4页
In the era of intelligent media,the interaction between teachers and students in higher education is undergoing a profound transformation.The model has shifted from one-way transmission to multi-agent,two-way collabor... In the era of intelligent media,the interaction between teachers and students in higher education is undergoing a profound transformation.The model has shifted from one-way transmission to multi-agent,two-way collaboration involving“teacher-student-AI(artificial intelligence)”.Interaction depth moves from surface Q&A to deep thought engagement,supported by instant,precise feedback and a blended virtual-physical space.New forms such as data-driven personalized interaction and immersive collaborative learning have emerged.However,this evolution brings significant challenges:over-reliance on technology may weaken cognitive autonomy;virtual interaction risks emotional detachment and trust erosion;ethical concerns like algorithmic bias and data privacy arise;teachers’roles become blurred;and evaluation systems lag behind technological advances.Future pathways should position AI as a supportive tool while upholding human centrality.Strengthening emotional connection through online-offline blending,reforming assessment to value process and growth,and empowering teachers as digitally literate“learning guides”and“emotional connectors”are key to building a healthy,sustainable interactive ecosystem. 展开更多
关键词 intelligent media era teacher-student interaction human-AI collaboration emotional engagement educational transformation digital literacy
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Similarity transformation-based modeling of the thermally-radiative tetra-hybrid Casson nanofluid flow over a nonlinear stretching sheet using the Clique polynomial collocation method
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作者 U.L.MANIKANTA K.J.GOWTHAM +1 位作者 B.J.GIREESHA P.VENKATESH 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期185-202,共18页
The flow of a tetra-hybrid Casson nanofluid(Al_(2)O_(3)-CuO-TiO_(2)-Ag/H_(2)O)over a nonlinear stretching sheet is investigated.The Buongiorno model is used to account for thermophoresis and Brownian motion,while ther... The flow of a tetra-hybrid Casson nanofluid(Al_(2)O_(3)-CuO-TiO_(2)-Ag/H_(2)O)over a nonlinear stretching sheet is investigated.The Buongiorno model is used to account for thermophoresis and Brownian motion,while thermal radiation is incorporated to examine its influence on the thermal boundary layer.The governing partial differential equations(PDEs)are reduced to a system of nonlinear ordinary differential equations(ODEs)with fully non-dimensional similarity transformations involving all independent variables.To solve the obtained highly nonlinear system of differential equations,a novel Clique polynomial collocation method is applied.The analysis focuses on the effects of the Casson parameter,power index,radiation parameter,thermophoresis parameter,Brownian motion parameter,and Lewis number.The key findings show that thermal radiation intensifies the thermal boundary layer,the Casson parameter reduces the velocity,and the Lewis number suppresses the concentration with direct relevance to polymer processing,coating flows,electronic cooling,and biomedical applications. 展开更多
关键词 similarity transformation nonlinear stretching sheet Casson parameter tetra-hybrid nanofluid thermal radiation Clique polynomial collocation method
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Navigating Global Exhibition Transformations:Charting a New Blueprint for Industry Development
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作者 Fu Zhichen 《China's Foreign Trade》 2026年第1期19-21,共3页
On January 23,2026,the second plenary session of the China Expo Forum for International Cooperation(CEFCO) convened in Wuhan,Hubei Province.Amid significant changes in the global exhibition landscape,participants shar... On January 23,2026,the second plenary session of the China Expo Forum for International Cooperation(CEFCO) convened in Wuhan,Hubei Province.Amid significant changes in the global exhibition landscape,participants shared recent developments,key data,and future trends in major markets,offering guidance for industry practitioners to drive progress. 展开更多
关键词 global exhibition landscape transformationS key data CEFCO China Expo Forum International Cooperation industry development market trends
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Anisotropy of Phase Transformation in Aluminum and Copper under Shock Compression:Atomistic Simulations and Neural Network Model
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作者 Evgenii V.Fomin Ilya A.Bryukhanov +1 位作者 Natalya A.Grachyova Alexander E.Mayer 《Computers, Materials & Continua》 2026年第4期548-577,共30页
It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range ... It is well known that aluminum and copper exhibit structural phase transformations in quasi-static and dynamic measurements,including shock wave loading.However,the dependence of phase transformations in a wide range of crystallographic directions of shock loading has not been revealed.In this work,we calculated the shock Hugoniot for aluminum and copper in different crystallographic directions([100],[110],[111],[112],[102],[114],[123],[134],[221]and[401])of shock compression using molecular dynamics(MD)simulations.The results showed a high pressure(>160 GPa for Cu and>40 GPa for Al)of the FCC-to-BCC transition.In copper,different characteristics of the phase transition are observed depending on the loading direction with the[100]compression direction being the weakest.The FCC-to-BCC transition for copper is in the range of 150–220 GPa,which is consistent with the existing experimental data.Due to the high transition pressure,the BCC phase transition in copper competes with melting.In aluminum,the FCC-to-BCC transition is observed for all studied directions at pressures between 40 and 50 GPa far beyond the melting.In all considered cases we observe the coexistence of HCP and BCC phases during the FCC-to-BCC transition,which is consistent with the experimental data and atomistic calculations;this HCP phase forms in the course of accompanying plastic deformation with dislocation activity in the parent FCC phase.The plasticity incipience is also anisotropic in bothmetals,which is due to the difference in the projections of stress on the slip plane for different orientations of the FCC crystal.MD modeling results demonstrate a strong dependence of the FCC-to-BCC transition on the crystallographic direction,in which the material is loaded in the copper crystals.However,MD simulations data can only be obtained for specific points in the stereographic direction space;therefore,for more comprehensive understanding of the phase transition process,a feed-forward neural network was trained using MD modeling data.The trained machine learning model allowed us to construct continuous stereographic maps of phase transitions as a function of stress in the shock-compressed state of metal.Due to appearance and growth of multiple centers of new phase,the FCC-to-BCC transition leads to formation of a polycrystalline structure from the parent single crystal. 展开更多
关键词 Molecular dynamics(MD) ALUMINUM COPPER shock wave polymorphic phase transformation polycrystalline structure neural network model
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Paving Pathways to Progress:Global South youth explore China’s agricultural innovation and rural transformation
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作者 LI XIAOYU 《ChinAfrica》 2026年第2期36-37,共2页
From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological p... From lecture halls in Beijing to villages in the mountains of southwest China,a group of young rural innovators from Global South countries recently embarked on a journey that connected policy thinking,technological practice and lived rural experience. 展开更多
关键词 paving pathways progress rural transformation global south youth lecture halls mountains southwest china chinas agricultural innovation beijing
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Empowering“Green Content”to Enhance“Gold Content”:Mechanisms and Pathways for the Green Transformation of China’s Foreign Trade
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作者 Song Xiaokang Gao Jiandong Long Kun 《China's Foreign Trade》 2026年第1期25-27,共3页
In the past few decades,China's foreign trade,leveraging its comprehensive industrial system,resilient supply chain,and factor cost advantages,has steadily constructed a global division of labor pattern as the“wo... In the past few decades,China's foreign trade,leveraging its comprehensive industrial system,resilient supply chain,and factor cost advantages,has steadily constructed a global division of labor pattern as the“world's factory”. 展开更多
关键词 supply chainand resilient supply chain industrial systemresilient factor cost advantageshas global division labor pattern foreign trade green transformation comprehensive industrial system
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CEFCO 2026 An Era of Transformation:Stronger Links,Smarter Futures
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作者 Zhou Dongyang 《China's Foreign Trade》 2026年第1期8-10,共3页
The China Expo Forum for International Cooperation(CEFCO)2026 was held in Wuhan,Hubei Province,China,on January 22.The opening ceremony was attended by Li Qing Shuang,Vice President of the China Council for the Promot... The China Expo Forum for International Cooperation(CEFCO)2026 was held in Wuhan,Hubei Province,China,on January 22.The opening ceremony was attended by Li Qing Shuang,Vice President of the China Council for the Promotion of International Trade(CCPIT);Zhu Yuji,Deputy Secretary of the Hubei Provincial Committee of the Communist Party of China;Sheng Yue Chun,Member of the Standing Committee of the Hubei Provincial Committee of the Communist Party of China and Secretary of the Wuhan Municipal Committee;Punita Bhansal,President of the Global Association of the Exhibition Industry(UFI);Marsha Flanagan,President and CEO of the International Association of Exhibitions and Events(IAEE);Vincent Polito,CEO of the Society of Independent Show Organizers(SISO);and Leonie Ashford,Board Member of the International Congress and Convention Association(ICCA). 展开更多
关键词 smarter futures China expo forum international cooperation cefco exhibition industry wuhan stronger links international cooperation transformation global association exhibition industry ufi
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一种面向地图综合建筑多边形化简的Transformer模型
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作者 刘鹏程 成晓强 +2 位作者 肖天元 杨敏 艾廷华 《测绘学报》 北大核心 2026年第1期124-137,共14页
针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为... 针对地图综合中建筑多边形化简方法依赖人工规则、自动化程度低且难以利用已有化简成果的问题,本文提出了一种基于Transformer机制的建筑多边形化简模型。该模型首先把建筑多边形映射至一定范围的网格空间,将建筑多边形的坐标串表达为网格序列,从而获取建筑多边形化简前后的Token序列,构建出建筑多边形化简样本对数据;随后采用Transformer架构建立模型,基于样本数据利用模型的掩码自注意力机制学习点序列之间的依赖关系,最终逐点生成新的简化多边形,从而实现建筑多边形的化简。在训练过程中,模型使用结构化的样本数据,设计了忽略特定索引的交叉熵损失函数以提升化简质量。试验设计包括主试验与泛化验证两部分。主试验基于洛杉矶1∶2000建筑数据集,分别采用0.2、0.3和0.5 mm 3种网格尺寸对多边形进行编码,实现了目标比例尺为1∶5000与1∶10000的化简。试验结果表明,在0.3 mm的网格尺寸下模型性能最优,验证集上的化简结果与人工标注的一致率超过92.0%,且针对北京部分区域的建筑多边形数据的泛化试验验证了模型的迁移能力;与LSTM模型的对比分析显示,在参数规模相近的条件下,LSTM模型无法形成有效收敛,并生成可用结果。本文证实了Transformer在处理空间几何序列任务中的潜力,且能够有效复用已有化简样本,为智能建筑多边形化简提供了具有工程实用价值的途径。 展开更多
关键词 地图综合 建筑多边形化简 TOKENIZATION transformer模型 上下文工程
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基于CNN-Transformer架构的电磁传播损耗预测算法
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作者 万勇 李骏杰 +1 位作者 孙伟峰 戴永寿 《现代电子技术》 北大核心 2026年第6期43-48,共6页
为了解决传统经验传播损耗模型预测精度不足的问题,提出一种基于CNN-Transformer架构的电磁传播损耗预测算法,通过构建回归模型进行精准的传播损耗预测。通过斯皮尔曼系数法提取有效特征,利用CNN提取与传播损耗预测高度相关的浅层特征,... 为了解决传统经验传播损耗模型预测精度不足的问题,提出一种基于CNN-Transformer架构的电磁传播损耗预测算法,通过构建回归模型进行精准的传播损耗预测。通过斯皮尔曼系数法提取有效特征,利用CNN提取与传播损耗预测高度相关的浅层特征,将从卫星图像中获取的传播路径上地物特征序列进行位置编码,增强对传播路径中不同地物特征顺序对传播损耗影响的理解。最后将CNN提取的浅层特征与位置编码后的地物特征输入到Transformer模型,通过多头自注意力机制捕捉特征间的全局关联性,从而有效校正传播损耗的预测结果。实验结果表明,所提出的CNN-Transformer方法显著降低了传播损耗预测的均方根误差(RMSE),达到了3.3745 dB,同时保持了0.8956的较高确定性系数(R^(2))。所提的电磁传播损耗预测算法为无线通信传播特性研究领域提供了参考,具有一定的应用价值。 展开更多
关键词 电磁传播 损耗预测 transformER CNN 斯皮尔曼系数法 地物类型 位置编码
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基于BSimilar优化PTransformer的光伏功率短期预测
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作者 张文广 蔡浩 +1 位作者 刘科 孙盼荣 《动力工程学报》 北大核心 2026年第1期77-84,102,共9页
为提高光伏功率短期预测的精度,提出了考虑光伏设备性能退化因素的相似日算法优化的分时段多通道独立光伏功率短期预测方法。首先,在PTransformer模型中用分时段与通道独立的方法来处理光伏输入数据,以降低空间复杂度及提高长时间数据... 为提高光伏功率短期预测的精度,提出了考虑光伏设备性能退化因素的相似日算法优化的分时段多通道独立光伏功率短期预测方法。首先,在PTransformer模型中用分时段与通道独立的方法来处理光伏输入数据,以降低空间复杂度及提高长时间数据序列的关注度。其次,运用Transformer的编码器模型,通过自身注意力机制捕捉光伏序列特征之间的依赖关系,进行光伏功率的短期预测。最后,运用夹角余弦距离计算相似度并考虑光伏设备性能退化因素确定相似日,利用其功率数据优化PTransformer模型,以改善功率数据的滞后性。结果表明:相比典型的光伏功率短期预测方法,所提方法训练速度更快,预测精准度更高,并且对复杂天气状况下的光伏功率也有较好的预测结果。 展开更多
关键词 光伏功率 短期预测 性能退化 贝叶斯分析 transformER 相似日
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Transformer架构驱动下的综采工作面矿压时序特征智能预测
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作者 杜锋 陈博 +7 位作者 王文强 浦海 杜雪明 李国栋 乔瑞 李鑫磊 徐杰 曹煜 《煤田地质与勘探》 北大核心 2026年第2期1-13,共13页
【背景】矿压预测是顶板灾害预警和管理的重要手段,是智能化矿井安全生产的前提和基础。开采过程中综采工作面环境复杂多变,导致基于电液控制系统采集的支架压力数据分布差异较大,预测困难。【方法】基于Transformer的矿压预测模型,使... 【背景】矿压预测是顶板灾害预警和管理的重要手段,是智能化矿井安全生产的前提和基础。开采过程中综采工作面环境复杂多变,导致基于电液控制系统采集的支架压力数据分布差异较大,预测困难。【方法】基于Transformer的矿压预测模型,使用线性插值填补缺失的矿压值,并使用滑动窗口算法调整训练时的矿压数据结构;针对矿压数据的时序特性,构建融合时序特征的输入序列,利用多头注意力(multi-head-attention)机制动态计算权重,根据数据本身自适应地聚焦关键时间步,从而有效捕捉复杂的非线性时序依赖,显著提升特征表征与预测能力,最后使用迁移学习方法,完成对上、中、下工作面支架工作阻力预测,并搭建基于矿压大数据的智能分析及预测平台。【结果和结论】使用多头注意力机制代替神经网络捕捉全局矿压数据特征,比循环神经网络(recurrent neural network,RNN)和长短期记忆网络(long short-term memory,LSTM)具有更强长序列依赖能力和特征学习能力,能有效降低模型损失,更加适用于预测矿压,Transformer模型在测试集上的均方误差和平均绝对误差损失精度分别达到0.34%和2.57%。Transformer模型也具有较强的泛化能力,使用迁移学习方法微调后,能够有效降低模型损失,在迁移同工作面其他支架时具有更好的泛化效果,Transformer预测模型进一步验证在矿压预测问题的适用性和可行性。平台可视化显示系统可精准分析预测前后的来压次数、推进距离、来压判据和工作面矿压云图等关键参数,为顶板灾害预警乃至其他灾害预警提供新思路,也为矿井安全高效开采与智能化建设奠定了坚实基础。 展开更多
关键词 综采工作面 深度学习 transformer模型 时间序列 矿压显现 矿压预测
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基于长短期记忆网络-Transformer模型参数优化的锂离子电池剩余使用寿命预测 被引量:1
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作者 高建树 郝世宇 党一诺 《汽车工程师》 2026年第1期32-39,共8页
为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transforme... 为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transformer的自注意力机制处理全局信息并对超参数进行优化,通过全连接层进行最终的寿命预测。基于美国国家航空航天局(NASA)数据集和先进生命周期工程中心(CALCE)数据集的试验验证结果表明,模型在更短的序列长度、更少的隐藏层数量和训练次数等条件下,在多种评价指标上均优于LSTM网络模型、Transformer模型及其他神经网络模型,具有更高的预测精度和鲁棒性。最后,通过不同电池的对比试验进一步验证了模型在不同电池数据上的泛化能力。 展开更多
关键词 锂离子电池 剩余使用寿命预测 参数优化 长短期记忆神经网络 transformER 混合模型
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