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Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
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作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
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Cell type-dependent role of transforming growth factor-βsignaling on postnatal neural stem cell proliferation and migration
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作者 Kierra Ware Joshua Peter +1 位作者 Lucas McClain Yu Luo 《Neural Regeneration Research》 2026年第3期1151-1161,共11页
Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postn... Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo. 展开更多
关键词 adult neurogenesis DOUBLECORTIN HIPPOCAMPUS MIGRATION neural stem cells PROLIFERATION transforming growth factor-β
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Optimal combination of substrate supply amount coupled with nutrient solution management program for cucumber planting
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作者 Zhen Kang Zhaoxi Jiang +5 位作者 Zhaolong Liu Peng Wang Caihong Zhang Maozhou Yuan Mengqi Bai Xiaohui Hu 《Horticultural Plant Journal》 2026年第1期136-148,共13页
Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development... Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development of mechanization,wide-row spacing substrate cultivation became an optimize mode of the greenhouse cucumber cultivation,aligning with the trend of intelligent agriculture.To determine the optimal nutrient solution supply amount(NS)and supply frequency(SF)for promoting the integrated growth of cucumber under wide-row spacing substrate cultivation,we explored the effects of substrate supply amount(SS),NS,and SF on cucumber yield,quality,and element utilization efficiency.A five-level quadratic orthogonal rotation combination design with three experimental factors(NS,SF,and SS)was implemented for 23 coupling treatments over three growing seasons,including spring(2022S and 2023S)and autumn(2022A).The technique for order preference by similarity to ideal solution(TOPSIS)combining weights based on game theory was applied to construct cucumber comprehensive growth evaluation model.Single and two experimental factors analyses revealed significant effects of single factors and the coupling of NS-SS,NS-SF and SS-SF on the integrated growth of cucumber for all three growing seasons.For the NS-SF-SS combination,the optimal parameters for comprehensive cucumber growth were determined as follows:levels of^(-1).68 for NS,-0.7 for SF,and^(-1).682 for SS in 2022A;-0.43 for NS,-0.06 for SF,and 0.34 for SS in 2022S;0.3 for NS,-0.02 for SF,and 0.04 for SS in 2023S.Furthermore,for SS ranges of 2.00-3.01,3.01-4.50,4.50-5.99,5.99-7.00(L·plant^(-1)),the corresponding NS and SF intervals maximizing cucumber integrated growth in spring were:0.28-0.30(L·plant^(-1))and 6(times·d^(-1)),0.26-0.30(L·plant^(-1))and 6(times·d^(-1)),0.25-0.30(L·plant^(-1))and 6(times·d^(-1)),0.23-0.30(L·plant^(-1))and 6(times·d^(-1)),respectively.With the same SS,the corresponding NS and SF intervals that maximized cucumber integrated growth in autumn were:0.10(L·plant^(-1))and 8(times·d^(-1)),0.18(L·plant^(-1))and 7(times·d^(-1)),0.30(L·plant^(-1))and 6(times·d^(-1)),0.49(L·plant^(-1))and 5(times·d^(-1)),respectively.The results provide a theoretical basis for solution management,and further in-depth research on cucumber cultivation. 展开更多
关键词 Cucumis sativus L. Comprehensive growth Irrigation frequency Nutrient solution Substrate supply amount Wide row spacing
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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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Effect and mechanism of Ti−O solid solution layer on interfacial bonding strength of cold roll bonded titanium/stainless steel laminated composite plate
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作者 Zhi-yan YANG Xue-feng LIU +1 位作者 Hong-ting CHEN Xin MA 《Transactions of Nonferrous Metals Society of China》 2026年第1期171-182,共12页
Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding str... Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective. 展开更多
关键词 titanium/stainless steel laminated composite plate Ti−O solid solution hardened layer interlocking interface formation mechanism interfacial bonding strength
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Realgar transforming solution is involved of JNK, P38 MAPK pathway in down-regulating Ras/MAPK pathway in Caenorhabditis elegans
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作者 LIU Dong-ling ZHI De-juan +4 位作者 WAN Feng-qi WANG Meng-qi ZHOU Ting BAI Yan-li LI Hong-yu 《中国药理学与毒理学杂志》 CAS 北大核心 2019年第9期690-691,共2页
OBJECTIVE To investigate the effect and the mechanisms of realgar transforming solution(RTS)on down-regulating over activated ras.METHODS we used the optimizing technical processes to obtain the RTS,and eval⁃uate the ... OBJECTIVE To investigate the effect and the mechanisms of realgar transforming solution(RTS)on down-regulating over activated ras.METHODS we used the optimizing technical processes to obtain the RTS,and eval⁃uate the mechanisms of RTS on down-regulating overactivated ras in Caenorhabditis elegans.RESULTS We found that the mRNA level of let60 and lin45 significantly decreased following exposure to RTS,but mRNA levels of mpk1 were not statistically significant in let60/ras(gf)mutant.RTS together with sorafenib(RAF inhibitors)significantly enhanced the activity of RTS on down-regulating overactivated ras more than RTS only,but 50μmol·L^-1 PD98059,a specific ERK inhibitor did not.Lin45 gene RNAi decreased the ability of RTS on down-regulating overactivated ras significantly,but mpk1 gene RNAi did not,indicating that the activity of RTS on down-regulating overactivated ras mainly through targeting to lin45/raf.In addition,RTS significantly increased mRNA level of pmk1/p38 and jnk1/jnk in let-60/ras(gf)mutant,50μmol·L^-1 SB203580(p38 inhibitor)and SP600125(JNK inhibitor)significantly attenuated the effects of RTS on down-regulating overactivated ras in some degree,and pmk1,jnk1 gene RNAi displayed the similar results,suggesting that P38 and JNK/MAPK pathways in some degree were involved in the effects of RTS on down-regulating overactivated ras in C.ele⁃gans.CONCLUSION Realgar transforming solution down-regulate the Ras/MAPK pathway through JNK and P38 MAPK pathways. 展开更多
关键词 realgar transforming solution C.elegans P38 JNK/MAPK pathway
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Support vector machine regression(SVR)-based nonlinear modeling of radiometric transforming relation for the coarse-resolution data-referenced relative radiometric normalization(RRN) 被引量:3
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作者 Jing Geng Wenxia Gan +2 位作者 Jinying Xu Ruqin Yang Shuliang Wang 《Geo-Spatial Information Science》 SCIE CSCD 2020年第3期237-247,I0004,共12页
Radiometric normalization,as an essential step for multi-source and multi-temporal data processing,has received critical attention.Relative Radiometric Normalization(RRN)method has been primarily used for eliminating ... Radiometric normalization,as an essential step for multi-source and multi-temporal data processing,has received critical attention.Relative Radiometric Normalization(RRN)method has been primarily used for eliminating the radiometric inconsistency.The radiometric trans-forming relation between the subject image and the reference image is an essential aspect of RRN.Aimed at accurate radiometric transforming relation modeling,the learning-based nonlinear regression method,Support Vector machine Regression(SVR)is used for fitting the complicated radiometric transforming relation for the coarse-resolution data-referenced RRN.To evaluate the effectiveness of the proposed method,a series of experiments are performed,including two synthetic data experiments and one real data experiment.And the proposed method is compared with other methods that use linear regression,Artificial Neural Network(ANN)or Random Forest(RF)for radiometric transforming relation modeling.The results show that the proposed method performs well on fitting the radiometric transforming relation and could enhance the RRN performance. 展开更多
关键词 Support Vector machine Regression(SVR) non-linear radiometric transforming relation Relative Radiometric Normalization(RRN) multi-source data
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An Efficient Approach for Transforming Unbalanced Transportation Problems into Balanced Problems in Order to Find Optimal Solutions
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作者 Abdur Rashid Md. Amirul Islam 《American Journal of Operations Research》 2024年第1期74-86,共13页
In operations research, the transportation problem (TP) is among the earliest and most effective applications of the linear programming problem. Unbalanced transportation problems reflect the reality of supply chain a... In operations research, the transportation problem (TP) is among the earliest and most effective applications of the linear programming problem. Unbalanced transportation problems reflect the reality of supply chain and logistics situations where the available supply of goods may not precisely match the demand at different locations. To deal with an unbalanced transportation problem (UTP), it is essential first to convert it into a balanced transportation problem (BTP) to find an initial basic feasible solution (IBFS) and hence the optimal solution. The present paper is concerned with introducing a new approach to convert an unbalanced transportation problem into a balanced one and as a consequence to obtain optimum total transportation cost. Numerical examples are provided to demonstrate the suggested method. 展开更多
关键词 Unbalanced Transportation Problem (UTP) Supply DEMAND Initial solution Optimal solution
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Auto-Bcklund transformation and exact solutions of Wick-type stochastic Burgers equation 被引量:2
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作者 陈彬 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期513-516,共4页
Burgers equation in random environment is studied. In order to give the exact solutions of random Burgers equation, we only consider the Wick-type stochastic Burgers equation which is the perturbation of the Burgers e... Burgers equation in random environment is studied. In order to give the exact solutions of random Burgers equation, we only consider the Wick-type stochastic Burgers equation which is the perturbation of the Burgers equation with variable coefficients by white noise W(t)=Bt, where Bt is a Brown motion. The auto-Baecklund transformation and stochastic soliton solutions of the Wick-type stochastic Burgers equation are shown by the homogeneous balance and Hermite transform. The generalization of the Wick-type stochastic Burgers equation is also studied. 展开更多
关键词 Wick-type stochastic Burgers equation auto-Baecklund transformation stochastic soliton solution white noise Hermite transform homogeneous balance principle
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High-resolution frequency-domain Radon transform and variable-depth streamer data deghosting 被引量:11
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作者 宋建国 宫云良 李珊 《Applied Geophysics》 SCIE CSCD 2015年第4期564-572,629,共10页
Receiver ghost reflections adversely affect variable-depth streamer (VDS) data acquisition. In addition, the frequency notches caused by the interference between receiver ghosts and primary waves strongly affect sei... Receiver ghost reflections adversely affect variable-depth streamer (VDS) data acquisition. In addition, the frequency notches caused by the interference between receiver ghosts and primary waves strongly affect seismic data processing and imaging. We developed a high-resolution Radon transform algorithm and used it to predict receiver ghosts from VDS data. The receiver ghost reflections are subtracted and removed from the raw data. We propose a forward Radon transform operator of VDS data in the frequency domain and, based on the ray paths of the receiver ghosts, we propose an inverse Radon transform operator. We apply the proposed methodology to model and field data with good results. We use matching and subtracting modules of commercially available seismic data processing software to remove the receiver ghosts. The frequency notches are compensated and the effective frequency bandwidth of the seismic data broadens. 展开更多
关键词 variable-depth streamer data deghosting Radon transform bandwidth
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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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融合群分解与Transformer-KAN的短期风速预测
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作者 史加荣 张思怡 《南京信息工程大学学报》 北大核心 2026年第1期60-68,共9页
针对风速固有的不稳定性,通过融合群分解(Swarm Decomposition,SWD)、Transformer和Kolmogorov-Arnold网络(KAN),提出一种SWD-Transformer-KAN预测模型.首先,利用SWD对原始风速数据进行分解,以提取关键特征.其次,针对每个被分解的子序列... 针对风速固有的不稳定性,通过融合群分解(Swarm Decomposition,SWD)、Transformer和Kolmogorov-Arnold网络(KAN),提出一种SWD-Transformer-KAN预测模型.首先,利用SWD对原始风速数据进行分解,以提取关键特征.其次,针对每个被分解的子序列,建立Transformer-KAN模型,所建模型充分利用了Transformer的时序处理能力和KAN的非线性逼近能力.最后,对所有子序列的预测结果进行叠加,得到最终的风速预测值.为了验证所提出模型的有效性,将其与其他模型进行实验对比,结果表明,SWD-Transformer-KAN模型具有最优的预测性能,其决定系数(R2)高达99.91%. 展开更多
关键词 风速预测 群分解 transformER Kolmogorov-Arnold网络
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Effects of Gabor transform parameters on signa time-frequency resolution
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作者 尹陈 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2006年第3期169-173,共5页
In this paper, it is described that the time-frequency resolution of geophysical signals is affected by the time window function attenuation coefficient and sampling interval and how such effects are eliminated effect... In this paper, it is described that the time-frequency resolution of geophysical signals is affected by the time window function attenuation coefficient and sampling interval and how such effects are eliminated effectively. Improving the signal resolution is the key to signal time-frequency analysis processing and has wide use in geophysical data processing and extraction of attribute parameters. In this paper, authors research the effects of the attenuation coefficient choice of the Gabor transform window function and sampling interval on signal resolution. Unsuitable parameters not only decrease the signal resolution on the frequency spectrum but also miss the signals. It is essential to first give the optimum window and range of parameters through time-frequency analysis simulation using the Gabor transform. In the paper, the suggestions about the range and choice of the optimum sampling interval and processing methods of general seismic signals are given. 展开更多
关键词 Gabor transform time-frequency analysis REsolution Gaussion window sampling interval.
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基于Transformer模型堤坝渗漏入口精准识别方法研究
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作者 梁越 赵硕 +4 位作者 喻金桃 许彬 张斌 龚胜勇 舒云林 《岩土工程学报》 北大核心 2026年第1期187-195,共9页
渗漏是堤坝工程面临的主要安全隐患,渗漏入口精确识别与定位对降低堤坝风险至关重要。通过堤坝渗漏入口示踪剂分布及其运移特征模拟数据,训练学习Transformer模型以确定最优参数条件并分析该条件下该模型的预测效果,进一步通过室内模型... 渗漏是堤坝工程面临的主要安全隐患,渗漏入口精确识别与定位对降低堤坝风险至关重要。通过堤坝渗漏入口示踪剂分布及其运移特征模拟数据,训练学习Transformer模型以确定最优参数条件并分析该条件下该模型的预测效果,进一步通过室内模型试验验证该模型的可靠性。研究表明:①当迭代次数达600次时,模型预测的流速最大值相对误差最小,且最大流速值坐标与真实渗漏入口坐标最为接近,预测效果最佳;在此条件下,当数据采集时长为50 s时,模型预测的流速最大值相对偏差最小,预测效果最优。②在最佳迭代次数和数据采集时长条件下,模型预测精度超过95%,渗漏入口大小和渗漏流量的预测值与真实值差异极小,且流速和位置预测相对误差均较低,其中位置预测相对误差低于5%。③将电导率试验采集数据转换为示踪剂浓度并输入至该模型进行流速分布预测,可知该模型能准确定位渗漏入口位置,且流速和渗漏入口坐标的预测平均相对误差均低于10%,进而验证了该模型在渗漏入口定位中的有效性与准确性。相关研究成果可为堤坝渗漏入口精确识别奠定理论基础和提供技术支撑。 展开更多
关键词 堤坝 渗漏入口 transformer模型 精准识别 室内模型试验
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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
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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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Multiple attenuation using λ–f domain high-resolution Radon transform 被引量:7
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作者 李志娜 李振春 +1 位作者 王鹏 徐强 《Applied Geophysics》 SCIE CSCD 2013年第4期433-441,511,共10页
The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the 2- fdomain high-resolution Radon transform based on t... The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the 2- fdomain high-resolution Radon transform based on the fast and modified parabolic Radon transform presented by Abbad. The introduction of a new variable 2 makes the transform operator frequency-independent. Thus, we need to calculate the transform operator and its inverse operator only once, which greatly improves the computational efficiency. Besides, because the primaries and multiples are distributed on straight lines with different slopes in the 2-fdomain, we can easily choose the filtering operator to suppress the multiples. At the same time, the proposed method offers the advantage of high-resolution Radon transform, which can greatly improve the precision of attenuating the multiples. Numerical experiments suggest that the multiples are well suppressed and the amplitude versus offset characteristics of the primaries are well maintained. Real data processing results further verify the effectiveness and feasibility of the method. 展开更多
关键词 λ-f domain high resolution parabolic Radon transform multiple attenuation
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Transformation and dissolution of second phases during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc 被引量:8
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作者 Kai Wen Bai-Qing Xiong +5 位作者 Yun-Qiang Fan Yong-An Zhang Zhi-Hui Li Xi-Wu Li Feng Wang Hong-Wei Liu 《Rare Metals》 SCIE EI CAS CSCD 2018年第5期376-380,共5页
The transformation and dissolution of Mg(Zn, Cu, Al)2 phase during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc were investigated by means of optical microscopy (OM), scanning electron microsco... The transformation and dissolution of Mg(Zn, Cu, Al)2 phase during solution treatment of an Al-Zn-Mg-Cu alloy containing high zinc were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX) and X-ray diffraction (XRD). The results show that solution temperature is the main factor influencing phase dissolution. With solution temperature increasing, the content of residual phases decreases. Phase transformation from Mg(Zn, Cu, Al)2 to S(Al2CuMg) occurs under solution temperature of 450, 460 and 465 ℃. Mg(Zn, Cu, Al)2 phase is directly dissolved into the matrix under solution temperature of 470 and 475 ℃, and no S(Al2CuMg) phase transformed from Mg(Zn, Cu, Al)2 phase is observed. The formation of S(Al2CuMg) phase is mainly controlled by Zn elemental diffusion. The mechanism of transformation and dissolution of second phases was investigated. At low temperature, the dissolution of Zn is faster than that of Mg and Cu, resulting in an appropriate condition to form S(Al2CuMg) phase. At high temperature, the dissolution of main alloying elements has no significant barrier among them to form S(Al2CuMg) phase. 展开更多
关键词 Al-Zn-Mg-Cu alloy Microstructure solution treatment Phase transformation
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A modified solution combustion method to superfine Gd_2O_3:Eu^(3+) phosphor:preparation,phase transformation and optical properties 被引量:10
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作者 叶信宇 高文贵 +2 位作者 夏李斌 聂华平 庄卫东 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第3期345-350,共6页
Cubic and monoclinic Gd2O3:Eu3+ phosphors in the range of nano-scale and submicron-scale were prepared by a modified solution combustion method.Coexistence of cubic and monoclinic phases was found in the highest lumin... Cubic and monoclinic Gd2O3:Eu3+ phosphors in the range of nano-scale and submicron-scale were prepared by a modified solution combustion method.Coexistence of cubic and monoclinic phases was found in the highest luminescent sample synthesized at 600 oC.In relation to commercial sample,the relative luminescence intensity was 49.8%.The shape of emission spectrum of the sample thus changed and the charge-transfer-state band of excitation spectrum slightly shift toward higher energies.With increasing the anneal... 展开更多
关键词 Gd2O3:Eu3+ phase transformation solution combustion method optical property rare earths
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Dynamic response of axially moving Timoshenko beams: integral transform solution 被引量:5
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作者 安晨 苏健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第11期1421-1436,共16页
The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary co... The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary conditions, respectively. The implementation of GITT approach for analyzing the forced vibration equation eliminates the space variable and leads to systems of second-order ordinary differential equations (ODEs) in time. The MATHEMATICA built-in function, NDSolve, is used to numerically solve the resulting transformed ODE system. The good convergence behavior of the suggested eigenfunction expansions is demonstrated for calculating the transverse deflection and the angle of rotation of the beam cross-section. Moreover, parametric studies are performed to analyze the effects of the axially moving speed, the axial tension, and the amplitude of external distributed force on the vibration amplitude of axially moving Timoshenko beams. 展开更多
关键词 axially moving Timoshenko beam transverse vibration integral transform hybrid solution
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Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy 被引量:1
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作者 Xin Zhou Dan Ma +7 位作者 Yi-Xiang He Jing Jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期110-125,共16页
BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.... BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.AIM To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus post-ESD.METHODS Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential ESD.Endoscopic examinations occurred on days 7 and 21 post-ESD.In vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was assessed.Profibrotic signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after ESD.After treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal layer.Additionally,the expression of fibrotic effector molecules was notably inhibited.Mechanistically,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/3.In vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen I.The 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated pEsF.CONCLUSION KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway. 展开更多
关键词 Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis
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