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Soliton Solutions of a Coupled KdV System via Backlund Transformation
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作者 CAO Xifang WU Yiheng +2 位作者 LU Yi XU Wenjing XIA Yutong 《应用数学》 北大核心 2025年第1期211-216,共6页
In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation ... In this paper we use Böcklund transformation to construct soliton solutions for a coupled KdV system.This system was first proposed by Wang in 2010.First we generalize the well-known Bäcklund transformation for the KdV equation to such coupled KdV system.Then from a trivial seed solution,we construct soliton solutions.We also give a nonlinear superposition formula,which allows us to generate multi-soliton solutions. 展开更多
关键词 KdV equation Coupled KdV system B¨acklund transformation SOLItoN
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Atomic-scale understanding of martensitic transformation and transition-induced twinning in deformed Fe-Mn alloys
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作者 ZHANG Hong-bo LI Hong-kui +2 位作者 OU Xiao-qin SHEN Jie SONG Min 《Journal of Central South University》 2025年第4期1211-1222,共12页
In the present study,molecular dynamic simulation(MD)was used to investigate the plastic deformation process of the Fe-Mn alloys with different Mn contents.The influences of Mn contents ranging from 10%to 30%(at%)on t... In the present study,molecular dynamic simulation(MD)was used to investigate the plastic deformation process of the Fe-Mn alloys with different Mn contents.The influences of Mn contents ranging from 10%to 30%(at%)on the deformation behavior and the controlling mechanism of the Fe-base alloys were analyzed.The results show that phase transformations and{112}<111>_(BCC)deformation twinning occur in all Fe-Mn alloys but follow different deformation paths.In the Fe-10%Mn alloy the deformation twinning mechanism obeys the FCC-related path,the Fe-20%Mn alloy involves both the FCC-and HCP-related paths,and the deformation of the Fe-30%Mn alloy is dominated by the HCP-related twinning path.The addition of Mn can increase the stacking fault energy and retard the activation of slip systems as well as the formation of stacking faults.Thus,a higher content of Mn can delay the FCC®ε-martensite and the subsequentε-martensite®BCC phase transition at the intersection of twoε-martensitic bands.Therefore,the addition of Mn alloying element increases the yield strength and reduces the elastic modulus of the Fe-Mn alloys.The formation of deformation twins will contribute to the work-hardening effect and delay the necking and fracture of alloys.It is expected that the results in the present study will provide theoretical reference for the design and optimization of high-performance steels. 展开更多
关键词 Fe-Mn steel tensile deformation molecular dynamics simulation phase transformation
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基于iAutoformer的地浸采铀溶浸液酸浓度预测研究
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作者 刘志锋 林芝宁 +4 位作者 阳奕汉 王如意 张传飞 梁大业 唐俊贤 《有色金属(冶炼部分)》 北大核心 2025年第5期89-98,共10页
在“碳达峰、碳中和”战略背景下,铀矿开采效率直接影响核能发展与能源转型进程。在酸法地浸采铀工艺中,精准预测溶浸液酸浓度对提升铀的浸出率、保护矿区环境及设备安全具有重要工程价值。提出了基于自相关机制和自注意力机制的iAutofo... 在“碳达峰、碳中和”战略背景下,铀矿开采效率直接影响核能发展与能源转型进程。在酸法地浸采铀工艺中,精准预测溶浸液酸浓度对提升铀的浸出率、保护矿区环境及设备安全具有重要工程价值。提出了基于自相关机制和自注意力机制的iAutoformer模型,通过对历史时间序列自相关性进行加权并滚动聚合,发掘序列的周期性并揭示更多隐藏因素,扩展了信息的利用率,从而获得更好的预测结果。试验平均结果表明,iAutoformer模型相较长短期记忆网络(Long Short-Term Memory,LSTM,2000)模型能够在小数值波动中发现序列变化规律,在试验平均结果中绝对误差(Mean Absolute Error,MAE)由0.232下降至0.205、均方误差(Mean Square Error,MSE)由0.089下降至0.072;相较iTransformer(Inverted Transformer,2023)及PatchTST(Patch Time Series Transformer,2022),模型在周期性变化明显的预测结果中更能拟合真实数值,MAE分别下降0.005、0.004,MSE均下降0.003。从地浸采铀现场生产环境角度出发提出预测方法,通过学习历史数据中的规律,对未来溶浸液酸浓度进行实时预测,能够有效地调节溶浸液酸浓度、提高生产效率、助力铀矿山的智能化转型。 展开更多
关键词 地浸采铀 深度学习 自相关机制 时间序列预测 TRANSFORMER
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如何提升高校科技成果转化绩效——基于TOE框架的组态分析 被引量:2
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作者 张亚明 赵科 《湖南师范大学教育科学学报》 北大核心 2025年第1期80-90,共11页
高校是科技成果的重要产出地,如何提升高校科技成果转化绩效是亟待解决的现实问题。以河北省23所高校为案例,基于TOE框架理论,运用fsQCA方法探究技术、组织、环境层面要素对高校科技成果转化绩效的多重并发影响,研究发现:高校科技成果... 高校是科技成果的重要产出地,如何提升高校科技成果转化绩效是亟待解决的现实问题。以河北省23所高校为案例,基于TOE框架理论,运用fsQCA方法探究技术、组织、环境层面要素对高校科技成果转化绩效的多重并发影响,研究发现:高校科技成果转化绩效不受单一必要条件影响,但人力技术水平、技术创新能力和政府支持力度是驱动转化绩效提升的核心条件;存在4种高转化绩效条件组态和2种非高转化绩效条件组态,二者具有非对称性,其中技术创新能力和机构制度环境缺失是导致非高转化绩效的重要原因;在一定条件下组织要素可与技术创新能力发挥等效作用,且TOE因素可按重要程度排列为“技术>环境>组织”。研究结论为高校制定科技成果转化绩效提升策略提供了参考,有助于实现教育、科技与经济协同联动,进一步深化产教融合。 展开更多
关键词 高校科技成果转化 toE框架 组态路径 产教融合
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航天器编队轨迹跟踪Port-Hamiltonian控制方法
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作者 刘俊 包素艳 +1 位作者 陈琪锋 郝文康 《国防科技大学学报》 北大核心 2025年第3期64-72,共9页
针对航天器编队相对运动构型时变轨迹跟踪控制问题,基于端口哈密顿(port-Hamiltonian,PH)模型和广义正则变换,采用互联阻尼分配无源控制(interconnection and damping assignment passivity-based control,IDA-PBC)算法设计了一种分布... 针对航天器编队相对运动构型时变轨迹跟踪控制问题,基于端口哈密顿(port-Hamiltonian,PH)模型和广义正则变换,采用互联阻尼分配无源控制(interconnection and damping assignment passivity-based control,IDA-PBC)算法设计了一种分布式协调控制律。通过对航天器编队线性动力学的PH建模和广义正则变换,得到轨迹跟踪误差PH系统。在拓扑结构连通且固定的假设下,利用相对运动误差PH系统模型,基于IDA-PBC算法推导出了考虑邻居航天器间相对误差的轨迹跟踪分布式协调控制律。数值仿真验证了控制律的有效性,结果表明,利用PH控制方法可以完成航天器编队轨迹跟踪控制,为航天器编队分布式协调控制提供了一种新的有效方法。 展开更多
关键词 航天器编队 广义正则变换 轨迹跟踪 IDA-PBC port-Hamiltonian
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MTTorch:面向MT-3000芯片和Transformer模型的PyTorch算子库实现与优化
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作者 王昊天 孙羽菲 +4 位作者 隋轶丞 王嘉豪 石昌青 方建滨 张玉志 《软件学报》 北大核心 2025年第8期3896-3916,共21页
随着Transformer类大模型的飞速发展,算力逐渐成为制约领域发展的瓶颈,如何根据加速器硬件的结构特性加速和优化大语言模型的训练性能已成为研究热点.面向天河新一代超算系统的加速芯片MT-3000,提出并实现了适用于CPU+DSP异构架构的PyTo... 随着Transformer类大模型的飞速发展,算力逐渐成为制约领域发展的瓶颈,如何根据加速器硬件的结构特性加速和优化大语言模型的训练性能已成为研究热点.面向天河新一代超算系统的加速芯片MT-3000,提出并实现了适用于CPU+DSP异构架构的PyTorch扩展库——MTTorch,其核心是一个多核并行的算子库,对Transformer类模型训练过程中的核心算子进行向量化实现和优化.同时,针对MT-3000架构特性,提出了面向多核DSP的高性能规约算法及乒乓算法,显著提升了算子的运算性能.MTTorch还具有很好的通用性,对于不同版本的PyTorch都可以动态链接库的形式进行加载,不改变PyTorch的原生实现.大量实验证明,实现的核心算子在MT-3000芯片上有着很好的性能,在单DSP簇上可以达到8倍的加速效果.利用MTTorch在多节点执行训练任务时有着接近线性的加速比,极大地提升了Transformer类模型在MT-3000芯片上的训练效率. 展开更多
关键词 Pytorch 高性能计算 Transformer模型 天河超级计算机 CPU+DSP异构计算 软件生态
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Hydration transformation behaviors of CO_(2) and excellent anti-inflammatory activity on RAW 264.7 cell
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作者 Wanping Zhang Yiting Gu +3 位作者 Xuyan Li Zhiyong Sun Chunhong Wei Dongmei Zhang 《日用化学工业(中英文)》 CAS 北大核心 2024年第11期1289-1297,共9页
Skin care products with carbonic acid(H_(2)CO_(3))have gained extensive attention worldwide.However,the conversion of CO_(2) to H_(2)CO_(3) is not stable,and the mechanism of the effect of H_(2)CO_(3) on skin care has... Skin care products with carbonic acid(H_(2)CO_(3))have gained extensive attention worldwide.However,the conversion of CO_(2) to H_(2)CO_(3) is not stable,and the mechanism of the effect of H_(2)CO_(3) on skin care has not been clearly proved.The hydration-dissolution behaviors of CO_(2) were investigated under different temperature,pH,and pressure conditions.Moreover,based on the phenomenon of CO_(2) hydration transformation,the inflammatory effect of CO_(2) hydrate on macrophages(RAW 264.7)was investigated.The result shows that the increase in temperature weakened the hydration of CO_(2),and the increase in pH and pressure both promoted the water-phase transformation of CO_(2).When pH<6,CO_(2) reacts with water to generate H_(2)CO_(3).When pH was between 6-7,the prompt solution was a mixture of H_(2)CO_(3) and HCO_(3)^(-).When the pH was between 7-9,they mainly generated HCO_(3)^(-).And when pH>9,CO_(2) solubility mainly converts to CO_(3)^(2-).Besides,CO_(2) can inhibit the secretion of inflammatory factors by RAW 264.7 cells by inhibiting the phosphorylation of the p38 protein.CO_(2) hydrate inhibited the expression of pro-inflammatory factors IL-6,TNF-α,and up-regulated the expression of anti-inflammatory factor IL-10.Furthermore,the anti-inflammatory molecular mechanism of CO_(2) hydration inhibited the MAPK signaling pathway by inhibiting the phosphorylation of p38.The hydration-dissolution behavior of CO_(2) was investigated.This work revealed the anti-inflammatory bioeffect of CO_(2) hydrate,providing a theoretical basis and application support for CO_(2) skin care products. 展开更多
关键词 CO_(2) hydration transformation anti-inflammatory effect skin care
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应用动态Token的融合特征的持续图像字幕生成
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作者 晋嘉利 余璐 《计算机工程与应用》 北大核心 2025年第4期176-191,共16页
基于自注意力的结构(如Transformer)在图像字幕生成任务中有着突出的性能优势。但在大多数方法中模型只在静态、同分布数据集上进行训练,而真实世界中的数据分布大多是非独立同分布的数据流,这种设置下的持续图像字幕生成任务更具有挑... 基于自注意力的结构(如Transformer)在图像字幕生成任务中有着突出的性能优势。但在大多数方法中模型只在静态、同分布数据集上进行训练,而真实世界中的数据分布大多是非独立同分布的数据流,这种设置下的持续图像字幕生成任务更具有挑战性。目前针对图像字幕生成的多模态任务的持续学习研究较少,缺乏更适用于基于自注意力模型的持续图像字幕生成方法。针对以上挑战提出了一种应用动态Token的融合特征的持续图像字幕生成方法。在Transformer中对图像字幕生成任务所涉及的不同模态的数据特征进行融合,并对融合特征进行正则化计算;为每一个子任务定义一个Token,Token将随着子任务的切换而变化,这种Token即为动态Token,相比于整个训练阶段只定义一个且被所有子任务共用的静态Token而言,动态Token更能保存每个子任务特有的信息和特点。利用这些动态任务Token和任务标识融合特征注意力模块进一步获得具有任务标识信息的融合特征,并在每个子任务训练结束后保存其对应的Token,以保持模型对旧任务的记忆和表达能力,减少模型对旧任务的灾难性遗忘。在MS-COCO和Flickr30k数据集上的实验结果表明,应用动态Token的融合特征的持续图像字幕生成方法在Transformer架构上优于所有基线方法。以CIDEr指标为例,所有训练任务结束后CIDEr指标的平均分数相较于微调和所有基线方法中的最优方法分别提高了31.06%和13.94%。 展开更多
关键词 图像字幕生成 持续学习 TRANSFORMER 融合特征 动态token 正则化
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Analysis of multi-factor influences of tilt-to-length coupling noise in a test mass interferometer
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作者 ZHAO Meng-yuan SHEN Jia +5 位作者 PENG Xiao-dong MA Xiao-shan YANG Zhen LIU He-shan MENG Xin ZHANG Jia-feng 《中国光学(中英文)》 北大核心 2025年第3期704-714,共11页
For space-borne gravitational wave detection missions based on the heterodyne interferometry principle,tilt-to-length(TTL)coupling noise is an important optical noise source,significantly influencing the accuracy of t... For space-borne gravitational wave detection missions based on the heterodyne interferometry principle,tilt-to-length(TTL)coupling noise is an important optical noise source,significantly influencing the accuracy of the measurement system.We present a method for analyzing TTL coupling noise under the joint influence of multiple factors.An equivalent simulated optical bench for the test mass interferometer was designed,and Gaussian beam tracing was adopted to simulate beam propagation.By simulating the interference signal,it can analyze the impact of various factors on the TTL coupling noise,including positional,beam parameters,detector parameters,and signal definition factors.On this basis,a random parameter space composed of multiple influential factors was constructed within a range satisfying the analysis requirement,and the corresponding simulation results from random sampling were evaluated via variance-based global sensitivity analysis.The calculated results of the main and total effect indexes show that the test mass rotation angle and the piston effect(lateral)significantly influence the TTL coupling noise in the test mass interferometer.The analysis provides a qualitative reference for designing and optimizing space-borne laser interferometry systems. 展开更多
关键词 space interferometry optical simulation tilt-to-length coupling noise
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Cloning scheme for multipartite entangled pure states via photonic quantum walk
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作者 WANG Guocui LIN Zhi +2 位作者 LI Xikun YANG Qing YANG Ming 《量子电子学报》 北大核心 2025年第2期206-216,共11页
The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes ... The no-cloning theorem has sparked considerable interest in achieving high-fidelity approximate quantum cloning.Most of the previous studies mainly focused on the cloning of single particle states,and cloning schemes used there are incapable of cloning quantum entangled states in multipartite systems.Few schemes were proposed for cloning multiparticle states,which consume more entanglement resources with loss of qubits,and the fidelity of the cloned state is relatively low.In this paper,cloning schemes for bipartite and tripartite entangled states based on photonic quantum walk and entanglement swapping are proposed.The results show that according to the proposed schemes,two high-fidelity(up to 0.75)cloned states can be obtained with less quantum resource consumption.Because of the simple cloning steps,few quantum resources and high fidelity,these schemes are both efficient and feasible.Moreover,this cloning machine eliminates the need for tracing out cloning machine,thereby minimizing resource waste. 展开更多
关键词 quantum optics entanglement cloning photonic quantum walk multipartite entanglement
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Optimizing the generation of second harmonic optical vortices from nonlinear photonic crystals
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作者 LIU Shiqiang ZHANG Xinyu +4 位作者 CHEN Yan LI Shifeng ZHAO Gang ZHU Shining HU Xiaopeng 《物理学进展》 北大核心 2025年第4期161-168,共8页
The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex... The generation of optical vortices from nonlinear photonic crystals(NPCs)with spatially modulated second-order nonlinearity offers a promising approach to extend the working wavelength and topological charge of vortex beams for various applications.In this work,the second harmonic(SH)optical vortex beams generated from nonlinear fork gratings under Gaussian beam illumination are numerically investigated.The far-field intensity and phase distributions,as well as the orbital angular momentum(OAM)spectra of the SH beams,are analyzed for different structural topological charges and diffraction orders.Results reveal that higher-order diffraction and larger structural topological charges lead to angular interference patterns and non-uniform intensity distributions,deviating from the standard vortex profile.To optimize the SH vortex quality,the effects of the fundamental wave beam waist,crystal thickness,and grating duty cycle are explored.It is shown that increasing the beam waist can effectively suppress diffraction order interference and improve the beam’s quality.This study provides theoretical guidance for enhancing the performance of nonlinear optical devices based on NPCs. 展开更多
关键词 optical vortex nonlinear photonic crystal second harmonic generation orbital angular momentum
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Study on correlation of thermal model to in-orbit data for infrared optical payloads on FY-3E/HIRAS-Ⅱ
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作者 LI Yu-Han YANG Bao-Yu +4 位作者 ZHANG Qiang GUO Zhi-Peng WU Yi-Nong TANG Xiao LI Shang-Ju 《红外与毫米波学报》 北大核心 2025年第3期394-405,共12页
The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precisio... The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads. 展开更多
关键词 thermal model intelligent correlation method surrogate model infrared optical payload FY-3E
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体育课堂教学数字化转型的机理、挑战与突破路向——基于TOE理论视角 被引量:1
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作者 李磊 李恬 刘斌 《沈阳体育学院学报》 北大核心 2025年第3期23-29,共7页
体育课堂教学数字化转型是推动学校体育高质量发展的必然要求。基于TOE理论视角,对体育课堂教学数字化转型的作用机理、现实挑战与突破路向进行深入分析。研究认为,体育课堂教学数字化转型的作用机理表现为:在技术层面,体育课堂教学数... 体育课堂教学数字化转型是推动学校体育高质量发展的必然要求。基于TOE理论视角,对体育课堂教学数字化转型的作用机理、现实挑战与突破路向进行深入分析。研究认为,体育课堂教学数字化转型的作用机理表现为:在技术层面,体育课堂教学数字化转型以数字技术构筑底层架构;在组织层面,全要素协同与“以学生为中心”的范式创新驱动体育课堂数字化转型;在环境层面,教育空间的多维构建保障体育课堂教学数字化转型过程。然而,当前转型过程中仍存现实挑战:数字化教学设施“量质不足”,“数字体育+”复合型人才匮乏;教学主体内生能力偏弱,组织协同联动机制缺乏;政策理念偏差,数字化路径不清晰。据此提出突破路向:推动数字化教学场景增量提质,拓宽“数字体育+”复合型人才培养渠道;提升教师的数字化转型内生能力,构建共享共建的组织间全要素联动机制;加强数字化转型政策的顶层设计,优化体育课堂教学环境保障体系。 展开更多
关键词 体育课堂教学 数字化转型 toE理论 学校体育 高质量发展
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Controllable phase transition of Al^(3+)induced manganese dioxide fromβ-toδ-type and their Al-dopedδ-type manganese dioxide for high-performance asymmetric supercapacitors
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作者 CHENG Xiao-yang ZHANG Li-hua +4 位作者 LI Ling-yan WU Hao ZHENG Jin-feng YAO Jia-rong LI Gui-fang 《Journal of Central South University》 2025年第6期2101-2113,共13页
Al-doped manganese dioxide(MnO_(2))was synthesized by simple hydrothermal method,and a controllable phase transition of the MnO_(2)crystal phase fromβtoδwas achieved.The effects of Al doping concentration on the str... Al-doped manganese dioxide(MnO_(2))was synthesized by simple hydrothermal method,and a controllable phase transition of the MnO_(2)crystal phase fromβtoδwas achieved.The effects of Al doping concentration on the structure and electrochemical properties of electrode materials were studied in detail.The results show that the controlled synthesis requires a synergy between KMnO_(4),MnCl_(2)and AlCl_(3),and that Al^(3+)plays an important role.Compared with the pure phase MnO_(2),the crystallinity of Al-doped MnO_(2)decreases and the specific surface area increases,which provides more active sites for the electrode material.When 3 mmol Al^(3+)is added,the prepared MnO_(2)-3 has the largest specific capacitance and the highest rate performance.The energy density of the asymmetric supercapacitor(ASC)with MnO_(2)-3 as the positive electrode and activated carbon(AC)as the negative electrode can reach 18.4 W·h/kg at the power density of 400 W/kg,and the capacity can maintain 90%of the initial value after 20000 cycles,indicating that Al-doped MnO_(2)has certain practical application value.This study provides favorable guidance for MnO_(2)as a high performance electrode material. 展开更多
关键词 Al doping MnO 2 phase transformation energy storage SUPERCAPACItoR
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社区教育数字化转型何以可能与何以可行——基于TOE框架的理论分析 被引量:1
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作者 黄家乐 《成人教育》 北大核心 2025年第2期28-34,共7页
当前,教育数字化转型已经成为推进高质量教育体系建设的重要引擎。社区教育数字化转型的内涵表征主要表现为学习场域从物理空间向虚实融合转型、学习资源从单向供给向智能共享转型、学习服务从静态管理向动态治理转型。借鉴TOE理论,社... 当前,教育数字化转型已经成为推进高质量教育体系建设的重要引擎。社区教育数字化转型的内涵表征主要表现为学习场域从物理空间向虚实融合转型、学习资源从单向供给向智能共享转型、学习服务从静态管理向动态治理转型。借鉴TOE理论,社区教育数字化转型要形成以技术赋能为逻辑起点、以组织赋权为逻辑链条、以环境赋责为逻辑旨归的基本框架。基于此,将强化技术支撑以推进数字联通的社区教育新基建、推进组织创变以构建多元协同的社区教育治理体系、加强环境建设以营造安全高效的社区教育数字生态作为实践进路,共同推进社区教育数字化转型实践落地。 展开更多
关键词 数字化转型 数字技术 社区教育 toE框架
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Interfacial thermal contact model for consolidation of multilayered saturated soils subjected to time-dependent heating and loading
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作者 TANG Ke-jie WEN Min-jie +4 位作者 TU Yuan WU Wen-bing XIE Jia-hao LIU Kai-fu WU Da-zhi 《Journal of Central South University》 2025年第6期2239-2255,共17页
Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to t... Heat transfers at the interface of adjacent saturated soil primarily through the soil particles and the water in the voids.The presence of water induces the contraction of heat flow lines at the interface,leading to the emergence of the thermal contact resistance effect.In this paper,four thermal contact models were developed to predict the thermal contact resistance at the interface of multilayered saturated soils.Based on the theory of thermal-hydro-mechanical coupling,semi-analytical solutions of thermal consolidation subjected to time-dependent heating and loading were obtained by employing Laplace transform and its inverse transformation.Thermal consolidation characteristics of multilayered saturated soils under four different thermal contact models were discussed,and the effects of thermal resistance coefficient,partition thermal contact coefficient,and temperature amplitude on the thermal consolidation process were investigated.The outcomes indicate that the general thermal contact model results in the most pronounced thermal gradient at the interface,which can be degenerated to the other three thermal contact models.The perfect thermal contact model overestimates the deformation of the saturated soil during the thermal consolidation.Moreover,the effect of temperature on consolidation properties decreases gradually with increasing interfacial contact thermal resistance. 展开更多
关键词 multilayered saturated soils thermal consolidation thermal contact resistance time-dependent loading Laplace transform
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Temperature error compensation method for fiber optic gyroscope based on a composite model of k-means,support vector regression and particle swarm optimization
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作者 CAO Yin LI Lijing LIANG Sheng 《Journal of Systems Engineering and Electronics》 2025年第2期510-522,共13页
As the core component of inertial navigation systems, fiber optic gyroscope (FOG), with technical advantages such as low power consumption, long lifespan, fast startup speed, and flexible structural design, are widely... As the core component of inertial navigation systems, fiber optic gyroscope (FOG), with technical advantages such as low power consumption, long lifespan, fast startup speed, and flexible structural design, are widely used in aerospace, unmanned driving, and other fields. However, due to the temper-ature sensitivity of optical devices, the influence of environmen-tal temperature causes errors in FOG, thereby greatly limiting their output accuracy. This work researches on machine-learn-ing based temperature error compensation techniques for FOG. Specifically, it focuses on compensating for the bias errors gen-erated in the fiber ring due to the Shupe effect. This work pro-poses a composite model based on k-means clustering, sup-port vector regression, and particle swarm optimization algo-rithms. And it significantly reduced redundancy within the sam-ples by adopting the interval sequence sample. Moreover, met-rics such as root mean square error (RMSE), mean absolute error (MAE), bias stability, and Allan variance, are selected to evaluate the model’s performance and compensation effective-ness. This work effectively enhances the consistency between data and models across different temperature ranges and tem-perature gradients, improving the bias stability of the FOG from 0.022 °/h to 0.006 °/h. Compared to the existing methods utiliz-ing a single machine learning model, the proposed method increases the bias stability of the compensated FOG from 57.11% to 71.98%, and enhances the suppression of rate ramp noise coefficient from 2.29% to 14.83%. This work improves the accuracy of FOG after compensation, providing theoretical guid-ance and technical references for sensors error compensation work in other fields. 展开更多
关键词 fiber optic gyroscope(FOG) temperature error com-pensation composite model machine learning CLUSTERING regression.
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基于BERTopic主题建模的“Assessing Writing”研究趋势演化分析
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作者 李锦焱 张丹 高慧敏 《河南科技大学学报(自然科学版)》 北大核心 2025年第4期97-104,M0008,共9页
通过深入挖掘期刊研究主题与预测学术发展趋势,研究人员能够更精准地把握学科方向,紧跟前沿动态。然而,期刊摘要作为短文本,其结构化特点、高维稀疏的向量表示、语义结构复杂性以及数据噪声等因素,对传统主题建模方法构成了严峻挑战。... 通过深入挖掘期刊研究主题与预测学术发展趋势,研究人员能够更精准地把握学科方向,紧跟前沿动态。然而,期刊摘要作为短文本,其结构化特点、高维稀疏的向量表示、语义结构复杂性以及数据噪声等因素,对传统主题建模方法构成了严峻挑战。针对这一问题,提出了一种基于BERTopic的主题演化分析模型。模型融合了预训练语言模型在语义表征方面的优势与层次化聚类算法的结构建模能力,同时重构词项加权策略,引入词频的次线性变换机制以优化传统词权计算方法,从而有效削弱高频词的干扰,突出对区分主题具有关键意义的词项,显著提升了模型的主题区分度和语义表征能力。以“Assessing Writing”期刊为研究对象,围绕不同时期写作评估领域的研究成果开展实证分析。通过系统梳理各阶段的研究主题与发展方向,挖掘其动态演化规律。实验结果表明,能够准确捕捉写作评估领域的研究热点变化,清晰揭示其发展脉络,在处理期刊摘要等短文本数据时展现出良好的实用性与有效性,为相关领域的学术研究和趋势预测提供了可靠的技术支撑。 展开更多
关键词 主题建模 BERtopic 语义结构 主题表征 次线性变换
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基于Stokes空间和Stacking模型的调制格式识别
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作者 刘昱 刘战胜 《光通信技术》 北大核心 2025年第3期108-113,共6页
为提高弹性光网络(EON)中调制格式识别(MFI)的准确性与鲁棒性,提出一种基于Stokes空间和Stacking模型的MFI方法。该方法通过核密度估计提取Stokes空间三轴的一维概率分布特征,构建240维特征向量;采用遗传算法优化Stacking模型的基模型... 为提高弹性光网络(EON)中调制格式识别(MFI)的准确性与鲁棒性,提出一种基于Stokes空间和Stacking模型的MFI方法。该方法通过核密度估计提取Stokes空间三轴的一维概率分布特征,构建240维特征向量;采用遗传算法优化Stacking模型的基模型与元模型组合,并利用贝叶斯优化调参,提升模型在低信噪比下的分类性能。仿真结果表明:在5~30dB光信噪比(OSNR)范围内,模型宏平均受试者工作特征曲线下的面积(AUC)为1,对偏振分复用-二进制相移键控(PDM-BPSK)、偏振分复用-四进制相移键控(PDM-QPSK)等调制格式的识别准确率超过98.5%,平均准确率较XGboost、Tabnet等对比模型提升2.05%~5.63%,且在OSNR为18dB时即可实现100%识别精度。 展开更多
关键词 弹性光网络 调制格式识别 集成学习 光信噪比
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企业数字化能力影响因素研究——基于TOE框架的ISM-MICMAC分析
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作者 陈於婷 蒋春燕 宋成文 《科技进步与对策》 北大核心 2025年第5期118-127,共10页
新一轮产业数字化变革中,数字化能力提升对企业可持续发展至关重要。为明晰数字化能力生成过程,在TOE框架下识别并提炼企业数字能力影响因素,综合使用ISM-MICMAC方法分析影响因素间的内在逻辑关系和层次结构,构建企业数字化能力影响因... 新一轮产业数字化变革中,数字化能力提升对企业可持续发展至关重要。为明晰数字化能力生成过程,在TOE框架下识别并提炼企业数字能力影响因素,综合使用ISM-MICMAC方法分析影响因素间的内在逻辑关系和层次结构,构建企业数字化能力影响因素解释结构模型。结果表明,企业数字化能力共19个影响因素可划分为8个层次;其中,数字化组织准备、数字技术运用与扩散既是直接影响因素,也是高依赖性因素;需求转变、政策导向、数字经济水平和高管数字背景是深层驱动力因素。结论基于系统视角丰富数字化能力前因研究,以期为企业在数字化转型过程中培育数字化能力提供理论依据。 展开更多
关键词 数字化能力 数字化转型 影响因素 解释结构模型
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