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Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method
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作者 WANG Xin SHEN Dejian +2 位作者 TAO Sijie LIU Ruixin WU Shengxing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期49-64,共16页
This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydra... This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S paste.The results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age. 展开更多
关键词 tricalcium silicate simulation method chloride diffusion coefficient pore solution
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Influence of Al,Cu and Mn additions on diffusion behaviors in CoCrFeNi high-entropy alloys
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作者 Juan CHEN Zhen-zhong ZHANG +1 位作者 Jin-kun XIAO Li-jun ZHANG 《中国有色金属学报》 北大核心 2025年第1期184-193,共10页
The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of ... The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged. 展开更多
关键词 Co−Cr−Fe−Ni high-entropy alloy diffusion interdiffusivity diffusion couple
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人工智能在绘画领域的应用——以Stable Diffusion搭配ControlNet为例
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作者 叶雨杭 雷雅琴 《科学与信息化》 2025年第2期60-63,共4页
文章分析了Stable Diffusion的技术原理与插件ControlNet的功能,以及两者结合之后出图的效果及优势和劣势。同时分析如何通过ComfyUI添加插件搭建工作流,以提升工作效率,减少工作时间。本文旨在通过应用人工智能技术将设计师从单一的重... 文章分析了Stable Diffusion的技术原理与插件ControlNet的功能,以及两者结合之后出图的效果及优势和劣势。同时分析如何通过ComfyUI添加插件搭建工作流,以提升工作效率,减少工作时间。本文旨在通过应用人工智能技术将设计师从单一的重复的工作中解放出来,专注于设计本身而不是设计绘画的过程,让数字绘画技术赋予绘画领域升级。 展开更多
关键词 AIGC 人工智能 数字绘画 平面设计 Stable diffusion CONTROLNET
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Air target intent recognition method combining graphing time series and diffusion models
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作者 Chenghai LI Ke WANG +2 位作者 Yafei SONG Peng WANG Lemin LI 《Chinese Journal of Aeronautics》 2025年第1期507-519,共13页
Air target intent recognition holds significant importance in aiding commanders to assess battlefield situations and secure a competitive edge in decision-making.Progress in this domain has been hindered by challenges... Air target intent recognition holds significant importance in aiding commanders to assess battlefield situations and secure a competitive edge in decision-making.Progress in this domain has been hindered by challenges posed by imbalanced battlefield data and the limited robustness of traditional recognition models.Inspired by the success of diffusion models in addressing visual domain sample imbalances,this paper introduces a new approach that utilizes the Markov Transfer Field(MTF)method for time series data visualization.This visualization,when combined with the Denoising Diffusion Probabilistic Model(DDPM),effectively enhances sample data and mitigates noise within the original dataset.Additionally,a transformer-based model tailored for time series visualization and air target intent recognition is developed.Comprehensive experimental results,encompassing comparative,ablation,and denoising validations,reveal that the proposed method achieves a notable 98.86%accuracy in air target intent recognition while demonstrating exceptional robustness and generalization capabilities.This approach represents a promising avenue for advancing air target intent recognition. 展开更多
关键词 Intent Recognition Markov Transfer Field Denoising diffusion Probability Model Transformer Neural Network
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GAN与Diffusion在传统纹样设计中的实验研究
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作者 李莉 毛子晗 +2 位作者 吕思奇 袁晨旭 彭玉旭 《丝绸》 CAS CSCD 北大核心 2024年第8期9-22,共14页
传统纹样是中国优秀传统文化的重要组成部分,传统人工设计已经无法满足纹样的现代设计需求,生成式AI为传统纹样设计提供了新的设计路径和方法。文章将生成式AI应用于传统纹样设计中,通过适配实验优选基于GAN的Style GAN和基于Diffusion... 传统纹样是中国优秀传统文化的重要组成部分,传统人工设计已经无法满足纹样的现代设计需求,生成式AI为传统纹样设计提供了新的设计路径和方法。文章将生成式AI应用于传统纹样设计中,通过适配实验优选基于GAN的Style GAN和基于Diffusion的Stable Diffusion两种主流图像生成模型进行实验,采用技术分析与艺术分析相结合,对实验结果进行多角度、多维度对比分析,为设计师选择生成设计方法提供参照。实验结果表明,两个模型均能满足基本的艺术设计需求。Style GAN模型生成的纹样图像更接近真实图像的分布,具有更高的图像质量和多样性;Stable Diffusion模型能较好地传承传统纹样的基因,艺术性与创造性兼具,更加符合传统纹样的艺术设计需求。 展开更多
关键词 GAN diffusion 传统纹样 评价指标 对比分析 实验研究
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基于Stable Diffusion的虚拟人形象预设计的应用与研究 被引量:3
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作者 曾建勇 沈晓萍 《现代信息科技》 2024年第3期169-175,共7页
对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同... 对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同采样参数及不同训练模型生成图片效果的优劣进行了说明及展示。随后,通过项目实例,完整地展示了人物形象预设计的过程。最后,对AIGC等新技术可能带来的社会影响进行了预测和总结。 展开更多
关键词 AI生成内容 Stable diffusion 生成对抗网络 提示词 虚拟人形象
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Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process 被引量:1
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作者 Yufeng Guo Jinlai Zhang +5 位作者 Shuai Wang Jianjun Fan Haokun Li Feng Chen Kuo Liu Lingzhi Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期485-497,共13页
The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking process.In this study,the interaction between calcium carbonate and iron or... The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking process.In this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple experiments.Scanning electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting process.The results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of preheating.With the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively slow.The order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 h.Ca_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed pellets.Furthermore,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed pellets.In addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed. 展开更多
关键词 fluxed iron ore pellet LIMESTONE HEMATITE QUARTZ diffusion reaction
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Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection 被引量:1
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作者 Cong Chang QuanMing Lu +2 位作者 San Lu Kai Huang RongSheng Wang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期472-478,共7页
Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic reconnection.The electron diffusion region(EDR),where the electron motions ar... Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic reconnection.The electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow direction.In the inner EDR,the speed of the electron outflow increases when the electrons move away from the X line.In the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer EDR.In the boundary of the outer EDR,the magnetic field piles up and forms a depolarization front.From the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been investigated.Around the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane direction.When the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron outflow.Both electric field forces and electron gradient forces tend to drag the electron outflow.Ion acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion outflow.Although these two terms are important,their effects on ions are almost offset.The Hall electric field force does positive work on ions and is not negligible.The ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front. 展开更多
关键词 collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation
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Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients 被引量:1
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作者 Hai-Bin Zhu Bo Zhao +3 位作者 Xiao-Ting Li Xiao-Yan Zhang Qian Yao Ying-Shi Sun 《World Journal of Gastroenterology》 SCIE CAS 2024年第4期308-317,共10页
BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindicatio... BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver resection.Up to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after resection.AIM To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to surgery.METHODS In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after chemotherapy.Various parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were measured.The parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node status.The reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation coefficient.RESULTS Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of 0.873.Furthermore,parameters from SEM showed substantial repeatability.CONCLUSION The developed nomogram,incorporating the pre-treatment DDC and the short axis of the largest lymph node,can be used to predict the presence of hepatic LNM in CRLM patients undergoing chemotherapy before surgery.This nomogram was proven to be more valuable,exhibiting superior diagnostic performance compared to quantitative parameters derived from multiple b values of DWI.The nomogram can serve as a preoperative assessment tool for determining the status of hepatic lymph nodes and aiding in the decision-making process for surgical treatment in CRLM patients. 展开更多
关键词 Colorectal cancer Individualized treatment diffusion magnetic resonance imaging Intravoxel incoherent motion LIVER
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AI绘画在艺术创作中的应用——以Stable Diffusion为例 被引量:2
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作者 李深森 《现代信息科技》 2024年第8期133-137,共5页
AI绘画是基于人工智能技术进行艺术创作的一种方法,在AI绘画中,Stable Diffusion可提供稳定、连续和高质量的图像生成。Stable Diffusion是一种基于生成对抗网络的图像生成方法,它通过不断更新图像的噪声分布,逐渐生成越来越逼真的图像... AI绘画是基于人工智能技术进行艺术创作的一种方法,在AI绘画中,Stable Diffusion可提供稳定、连续和高质量的图像生成。Stable Diffusion是一种基于生成对抗网络的图像生成方法,它通过不断更新图像的噪声分布,逐渐生成越来越逼真的图像。在绘画艺术创作中,Stable Diffusion能够激发创作者的灵感,帮助他们探索不同的创作风格和创作方式。与此同时,创作者仍需运用自己的审美判断力对所绘制的作品进行筛选和调整。 展开更多
关键词 AI绘画 Stable diffusion 艺术创作
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A high Li-ion diffusion kinetics in multidimensional and compact-structured electrodes via vacuum filtration casting 被引量:1
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作者 Jieqiong Li Ting Ouyang +3 位作者 Lu Liu Shu Jiang Yongchao Huang M.-Sadeeq Balogun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期368-376,I0010,共10页
Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is ... Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is desirable but remains a significant challenge.In this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(LiFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration approach.Both as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell configuration.The assembled MNC-20‖MLC-20 full cell LIB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),respectively.The excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid Li-ion diffusion kinetics.Furthermore,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture. 展开更多
关键词 Thick electrodes Carbon nanotubes Li-ion diffusion co-efficient Vacuum filtration technique High areal capacity Lithium-ion batteries
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人工智能技术对景观设计的影响与探究--以Stable Diffusion为例
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作者 姚杰 石雨柯 莫敷建 《鞋类工艺与设计》 2024年第23期20-22,共3页
本文将通过分析Stable Diffusion(稳定扩散)技术原理,并提出人工智能AI(Artificial Intelligence)技术迅速发展的背景下阐述AI绘画的核心技术,以Stable Diffusion为例对景观设计行业所面临的问题展开探讨。首先分析Stable Diffusion技术... 本文将通过分析Stable Diffusion(稳定扩散)技术原理,并提出人工智能AI(Artificial Intelligence)技术迅速发展的背景下阐述AI绘画的核心技术,以Stable Diffusion为例对景观设计行业所面临的问题展开探讨。首先分析Stable Diffusion技术概念、对比Stable Diffusion设计制图方法与传统制图手法;其次结合Stable Diffusion技术分析现今景观设计在行业中的机遇与挑战;最后总结在人工智能技术背景下对景观设计未来发展是否具有创造力以及对待人工智能技术的辩证态度,以期为相关人士提供研究思路。 展开更多
关键词 Stable diffusion 景观设计 人工智能
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Influence of Al foil interlayer on performance of vacuum diffusion bonding joint of 6061 aluminium alloy
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作者 Da-shuang Liu Jian-hua Xu +9 位作者 Xiong-hui Li Ping Wei Yun Liang Jian Qin Hua-wei Sun Tian-ran Ding Zong-ye Ding Su-juan Zhong Lei Zhang Wei-min Long 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2024年第10期2404-2412,共9页
The vacuum diffusion bonding method was used to introduce Al foil as the middle layer,and 6061 aluminium alloy was vacuum diffusion bonding together.The typical microstructure characteristics and mechanical properties... The vacuum diffusion bonding method was used to introduce Al foil as the middle layer,and 6061 aluminium alloy was vacuum diffusion bonding together.The typical microstructure characteristics and mechanical properties of 6061/Al/6061 welded joints were studied in detail,the effects of process parameters and Al intermediate layer on the microstructure and mechanical properties were revealed,and the diffusion bonding mechanism of 6061/Al/6061 welded joints was described.Al foil middle layer welded joint had the best performance at the temperature of 540℃,the holding time of 120 min,and the welding pressure of 4 MPa.The bonding ratio is 95.91%,the shear strength is 79 MPa,and the deformation rate is 8.05%,and the introduction of Al intermediate layer improves the element distribution and microstructure,so that the bonding ratio of the welded joint is increased by 10.86%,the shear strength is increased by 5.55 MPa,and the deformation rate is reduced by 1.58%.The fracture morphology has typical ductile fracture characteristics. 展开更多
关键词 6061 aluminium alloy diffusion bonding INTERLAYER Joint performance Elemental diffusion
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Research on the correlation between the dual diffusion behavior of zinc in InGaAs/InP single-photon avalanche photodiodes and device performance
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作者 LIU Mao-Fan YU Chun-Lei +7 位作者 MA Ying-Jie YU Yi-Zhen YANG Bo TIAN Yu BAO Peng-Fei CAO Jia-Sheng LIU Yi LI Xue 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第5期595-602,共8页
The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribu... The development of InGaAs/InP single-photon avalanche photodiodes(SPADs)necessitates the utiliza-tion of a two-element diffusion technique to achieve accurate manipulation of the multiplication width and the dis-tribution of its electric field.Regarding the issue of accurately predicting the depth of diffusion in InGaAs/InP SPAD,simulation analysis and device development were carried out,focusing on the dual diffusion behavior of zinc atoms.A formula of X_(j)=k√t-t_(0)+c to quantitatively predict the diffusion depth is obtained by fitting the simulated twice-diffusion depths based on a two-dimensional(2D)model.The 2D impurity morphologies and the one-dimensional impurity profiles for the dual-diffused region are characterized by using scanning electron micros-copy and secondary ion mass spectrometry as a function of the diffusion depth,respectively.InGaAs/InP SPAD devices with different dual-diffusion conditions are also fabricated,which show breakdown behaviors well consis-tent with the simulated results under the same junction geometries.The dark count rate(DCR)of the device de-creased as the multiplication width increased,as indicated by the results.DCRs of 2×10^(6),1×10^(5),4×10^(4),and 2×10^(4) were achieved at temperatures of 300 K,273 K,263 K,and 253 K,respectively,with a bias voltage of 3 V,when the multiplication width was 1.5µm.These results demonstrate an effective prediction route for accu-rately controlling the dual-diffused zinc junction geometry in InP-based planar device processing. 展开更多
关键词 InGaAs/InP single-photon avalanche photodiode diffusion depth Znic diffusion dark count rate
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Erratum to:Unraveling engineering disturbance effects on deformation in red-bed mudstone railway cuttings:incorporating crack-facilitated moisture diffusion
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作者 HUANG Kang DAI Zhangjun +3 位作者 YAN Chengzeng YAO Junkai CHI Zecheng CHEN Shanxiong 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2870-2870,共1页
Erratum to:J.Mt.Sci.(2024)21(5):1663-1682 https://doi.org/10.1007/s11629-023-8561-0 During the production process,the first author’s name was wrongly written as“Rang Huang”in the metadata.The correct name for the f... Erratum to:J.Mt.Sci.(2024)21(5):1663-1682 https://doi.org/10.1007/s11629-023-8561-0 During the production process,the first author’s name was wrongly written as“Rang Huang”in the metadata.The correct name for the first author is“Kang Huang”.The first author’s name in the fulltext pdf is correct. 展开更多
关键词 MOISTURE MUDSTONE diffusion
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ON MONOTONE TRAVELING WAVES FOR NICHOLSON'S BLOWFLIES EQUATION WITH DEGENERATE p-LAPLACIAN DIFFUSION
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作者 Rui HUANG Yong WANG Zhuo YIN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1550-1571,共22页
We study the existence and stability of monotone traveling wave solutions of Nicholson's blowflies equation with degenerate p-Laplacian diffusion.We prove the existence and nonexistence of non-decreasing smooth tr... We study the existence and stability of monotone traveling wave solutions of Nicholson's blowflies equation with degenerate p-Laplacian diffusion.We prove the existence and nonexistence of non-decreasing smooth traveling wave solutions by phase plane analysis methods.Moreover,we show the existence and regularity of an original solution via a compactness analysis.Finally,we prove the stability and exponential convergence rate of traveling waves by an approximated weighted energy method. 展开更多
关键词 degenerate diffusion P-LAPLACIAN traveling waves stability
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3D robust anisotropic diffusion filtering algorithm for sparse view neutron computed tomography 3D image reconstruction
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作者 Yang Liu Teng-Fei Zhu +1 位作者 Zhi Luo Xiao-Ping Ouyang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期13-29,共17页
The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed images.Various types of noise in the system can d... The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed images.Various types of noise in the system can degrade the quality of the reconstructed images.Therefore,to improve the quality of the reconstructed images of NCT systems,efficient image processing algorithms must be used.The anisotropic diffusion filtering(ADF) algorithm can not only effectively suppress the noise in the projection data,but also preserve the image edge structure information by reducing the diffusion at the image edges.Therefore,we propose the application of the ADF algorithm for NCT image reconstruction.To compare the performance of different algorithms in NCT systems,we reconstructed images using the ordered subset simultaneous algebraic reconstruction technique(OS-SART) algorithm with different regular terms as image processing algorithms.In the iterative reconstruction,we selected two image processing algorithms,the Total Variation and split Bregman solved total variation algorithms,for comparison with the performance of the ADF algorithm.Additionally,the filtered back-projection algorithm was used for comparison with an iterative algorithm.By reconstructing the projection data of the numerical and clock models,we compared and analyzed the effects of each algorithm applied in the NCT system.Based on the reconstruction results,OS-SART-ADF outperformed the other algorithms in terms of denoising,preserving the edge structure,and suppressing artifacts.For example,when the 3D Shepp–Logan was reconstructed at 25 views,the root mean square error of OS-SART-ADF was the smallest among the four iterative algorithms,at only 0.0292.The universal quality index,mean structural similarity,and correlation coefficient of the reconstructed image were the largest among all algorithms,with values of 0.9877,0.9878,and 0.9887,respectively. 展开更多
关键词 NCT OS-SART Sparse-view Anisotropic diffusion filtering
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Shape and diffusion instabilities of two non-spherical gas bubbles under ultrasonic conditions
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作者 包乌日汗 王德鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期715-721,共7页
Ultrasonic cavitation involves dynamic oscillation processes induced by small bubbles in a liquid under the influence of ultrasonic waves. This study focuses on the investigation of shape and diffusion instabilities o... Ultrasonic cavitation involves dynamic oscillation processes induced by small bubbles in a liquid under the influence of ultrasonic waves. This study focuses on the investigation of shape and diffusion instabilities of two bubbles formed during cavitation. The derived equations for two non-spherical gas bubbles, based on perturbation theory and the Bernoulli equation, enable the analysis of their shape instability. Numerical simulations, utilizing the modified Keller–Miksis equation,are performed to examine the shape and diffusion instabilities. Three types of shape instabilities, namely, Rayleigh–Taylor,Rebound, and parametric instabilities, are observed. The results highlight the influence of initial radius, distance, and perturbation parameter on the shape and diffusion instabilities, as evidenced by the R_0–P_a phase diagram and the variation pattern of the equilibrium curve. This research contributes to the understanding of multiple bubble instability characteristics, which has important theoretical implications for future research in the field. Specifically, it underscores the significance of initial bubble parameters, driving pressure, and relative gas concentration in determining the shape and diffusive equilibrium instabilities of non-spherical bubbles. 展开更多
关键词 non-spherical bubble shape instability diffusive instability
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Tuning the diffusion constant to optimize the readout of positional information of spatial concentration patterns
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作者 江嘉杰 罗春雄 刘峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期579-586,共8页
Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative dif... Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative diffusion process.Here we study one-dimensional patterning systems with analytical derivation and numerical simulations.We find that the diffusion constant of the patterning molecules exhibits a nonmonotonic effect on the readout of the positional information from the concentration patterns.Specifically,there exists an optimal diffusion constant that maximizes the positional information.Moreover,we find that the energy dissipation due to the physical diffusion imposes a fundamental upper limit on the positional information. 展开更多
关键词 pattern formation positional information mutual information diffusion
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A Comprehensive Survey of Recent Transformers in Image,Video and Diffusion Models
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作者 Dinh Phu Cuong Le Dong Wang Viet-Tuan Le 《Computers, Materials & Continua》 SCIE EI 2024年第7期37-60,共24页
Transformer models have emerged as dominant networks for various tasks in computer vision compared to Convolutional Neural Networks(CNNs).The transformers demonstrate the ability to model long-range dependencies by ut... Transformer models have emerged as dominant networks for various tasks in computer vision compared to Convolutional Neural Networks(CNNs).The transformers demonstrate the ability to model long-range dependencies by utilizing a self-attention mechanism.This study aims to provide a comprehensive survey of recent transformerbased approaches in image and video applications,as well as diffusion models.We begin by discussing existing surveys of vision transformers and comparing them to this work.Then,we review the main components of a vanilla transformer network,including the self-attention mechanism,feed-forward network,position encoding,etc.In the main part of this survey,we review recent transformer-based models in three categories:Transformer for downstream tasks,Vision Transformer for Generation,and Vision Transformer for Segmentation.We also provide a comprehensive overview of recent transformer models for video tasks and diffusion models.We compare the performance of various hierarchical transformer networks for multiple tasks on popular benchmark datasets.Finally,we explore some future research directions to further improve the field. 展开更多
关键词 TRANSFORMER vision transformer self-attention hierarchical transformer diffusion models
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