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基于VMD-SSA-ICA的ADS-B信号解交织算法研究
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作者 张召悦 董冠廷 鲍水达 《空军工程大学学报》 北大核心 2026年第1期41-47,57,共8页
针对在广播式自动相关监视信号在低信噪比,低相对延时的情况下解交织成功率低的问题,提出了基于VMD-SSA-ICA的ADS-B信号解交织方法。该方法首先采用变分模态分解方法对交织信号进行模态分解。其次基于奇异谱分析方法对各个模态进行重构... 针对在广播式自动相关监视信号在低信噪比,低相对延时的情况下解交织成功率低的问题,提出了基于VMD-SSA-ICA的ADS-B信号解交织方法。该方法首先采用变分模态分解方法对交织信号进行模态分解。其次基于奇异谱分析方法对各个模态进行重构,消除模态混叠,有效地分析ADS-B信号的潜在结构;然后用独立成分分析算法进行解交织。最后利用Dn-CNN神经网络对输出信号进行去噪处理,实现了信号分离与去噪的一体化。实验结果表明,该方法能够在信噪比为8~15 dB的情况下,分别实现60.92%~99.94%的信号解码成功率;针对不同信号相对时延的实验结果表明,算法在相对时延为0~10μs的情况下仍保持稳定的解交织性能。由此可见,该方法显著提升了ADS-B信号解交织算法的鲁棒性和抗干扰能力。 展开更多
关键词 ADS-B信号 信号交织 模态分解 独立成分分析 VMD-ssa-ICA
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基于SSA-BP神经网络的库区边坡变形时序预测研究
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作者 武益民 张成良 张焕雄 《水电能源科学》 北大核心 2026年第1期177-181,共5页
针对库区边坡位移预测中存在的复杂非线性及不确定性难题,构建了一种基于智能优化算法的混合预测模型SSA-BP,旨在克服传统BP网络训练速度慢、易陷入局部最优的局限,从而提升边坡位移预测的精度和鲁棒性。通过麻雀搜索算法SSA对BP神经网... 针对库区边坡位移预测中存在的复杂非线性及不确定性难题,构建了一种基于智能优化算法的混合预测模型SSA-BP,旨在克服传统BP网络训练速度慢、易陷入局部最优的局限,从而提升边坡位移预测的精度和鲁棒性。通过麻雀搜索算法SSA对BP神经网络的初始权值和阈值进行全局优化,增强其收敛效率和适应性,并基于张家湾边坡历时5个月的真实位移监测数据进行训练。为验证模型优势,将SSA-BP模型与基于遗传算法(GA)和粒子群算法(PSO)优化的BP网络进行性能比对。研究表明,模型在24次迭代内快速收敛,显著优于对比模型,其均方根误差(RRMSE)、平均绝对百分比误差(M MAPE)、决定系数(R2)等评价指标均表现最佳。SSA-BP模型为库区边坡位移预测提供了一种可靠且高效的智能方法。 展开更多
关键词 库区边坡 位移变形预测 麻雀搜索算法(ssa) BP网络模型优化
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基于SSA去噪的级联LSTM网络地球极移短期预报方法
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作者 张文渊 彭劲松 +2 位作者 韦纳都 高雨 张书毕 《测绘学报》 北大核心 2026年第1期46-58,共13页
地球极移是深空探测和卫星精密定轨的关键参数,其高精度预报模型是空间大地测量领域的研究热点。针对长短期记忆(LSTM)神经网络在短期预测中由于训练场景与应用场景不一致而导致的预测误差累积以及忽略信号噪声影响的问题,本文提出了一... 地球极移是深空探测和卫星精密定轨的关键参数,其高精度预报模型是空间大地测量领域的研究热点。针对长短期记忆(LSTM)神经网络在短期预测中由于训练场景与应用场景不一致而导致的预测误差累积以及忽略信号噪声影响的问题,本文提出了一种基于奇异谱分析(SSA)去噪的级联LSTM网络地球极移短期预报方法。该方法首先利用SSA算法剔除极移时序信号的高频噪声项,随后充分考虑未来不同预测天数的场景特征变化,通过级联架构实现前序子模型输出与后续子模型输入的误差抵偿传导,构建了多个子模型相互连接、逐级传递的级联式LSTM框架。利用1984—2024年的EOP 20 C04序列数据进行了试验验证,结果表明:对于1~10天的短期预报,本文方法在极移X和Y方向的预测结果的平均绝对误差(MAE)分别为1.70和0.93 mas,相较于递归LSTM模型的MAE分别降低了42.8%和48.1%,同时相较于SSA-递归LSTM模型的预报精度分别提升了11.1%和28.8%。此外,本文模型在未来6~10天的极移预报中具有显著优势,论证了本文方法可有效抑制预报误差积累,提高中后期预报精度,将模型预报结果应用于卫星轨道的天球坐标系与地球坐标系转换,显著提升了坐标转换精度。 展开更多
关键词 地球极移 短期预报 ssa 级联LSTM 去噪优化
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基于KPCA-ISSA-KELM的铁路隧道煤与瓦斯突出预测模型
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作者 李时宜 代鑫 +2 位作者 刘骞 左明辉 高旭 《铁道标准设计》 北大核心 2026年第1期143-151,共9页
为了能够更为准确地预测铁路隧道煤与瓦斯突出,有效保障铁路隧道施工安全性。首先根据煤与瓦斯突出影响因素,选取瓦斯压力、地质构造、瓦斯放散初速度、煤体结构类型、煤体坚固系数和埋深作为耦合指标,由SPSS 27软件通过皮尔逊相关系数... 为了能够更为准确地预测铁路隧道煤与瓦斯突出,有效保障铁路隧道施工安全性。首先根据煤与瓦斯突出影响因素,选取瓦斯压力、地质构造、瓦斯放散初速度、煤体结构类型、煤体坚固系数和埋深作为耦合指标,由SPSS 27软件通过皮尔逊相关系数矩阵分析各指标间的相关性,而后利于核主成分分析法(KPCA)对原始数据进行主成分提取。其次引入Sine混沌映射、动态自适应权重、Levy飞行策略以及融合柯西变异的反向学习对麻雀搜索算法(SSA)进行改进,以提升其全局搜索能力,而后利用改进的麻雀搜索算法(ISSA)优化KELM中核参数γ和正则化系数C,构建一种基于KPCA-ISSA-KELM的铁路隧道煤与瓦斯突出预测模型。引入PSO-BPNN、PSO-SVM、SSA-SVM模型,对比测试原始数据和降维后的数据,表明使用KPCA进行数据处理能够提升模型预测准确率,同时由其预测结果可知,在使用KPCA降维后的数据时,ISSA-KELM模型相较于其他模型在测试样本中的Ac分别提高0.22、0.22、0.11,P分别提高0.2、0.23、0.1,R分别提高0.24、0.25、0.14,F1-Score分别提高0.22、0.24、0.12。最后,将ISSA-KELM模型应用于西南部某铁路隧道,验证该模型的可靠性和稳定性,表明其更适合于铁路隧道煤与瓦斯突出预测,可为相似瓦斯隧道设计与施工提供借鉴。 展开更多
关键词 瓦斯隧道 煤与瓦斯突出 核主成分分析(KPCA) 麻雀搜索算法(ssa) 核极限学习机(KELM) 预测模型
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:2
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Drone-Based IoT Monitoring of Urban CO₂Levels in Makassar:Spatio-Temporal Analysis Across Varying Heights
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作者 Putri Ida Sunaryathy Samad Dewiani Jamaluddin +1 位作者 Alimuddin Sa’ban Miru Mithen Lullulangi 《Journal of Environmental & Earth Sciences》 2025年第8期317-332,共16页
Urban air quality degradation from rising CO_(2) is acute in rapidly developing tropical cities such as Makassar,Indonesia.We deploy a drone-based Internet of Things(IoT)platform for real-time CO_(2) monitoring,integr... Urban air quality degradation from rising CO_(2) is acute in rapidly developing tropical cities such as Makassar,Indonesia.We deploy a drone-based Internet of Things(IoT)platform for real-time CO_(2) monitoring,integrating low-cost sensors(NDIR,MQ135,MG811)on a DJI Phantom 4 with cloud streaming to Firebase.Measurements were collected at five sites,namely Jl.AP.Pettarani,Jl.Ahmad Yani,Jl.Sultan Hasanuddin,Jl.Nusantara,and KIMA at 08:00,12:00,and 16:00 in September 2024 while vertically profiling 1-20 m with three repeat flights per site and time.Descriptive statistics and one-way ANOVA with Tukey HSD assessed spatio-temporal differences;Pearson correlation quantified cross-sensor agreement.Results show marked spatial and diurnal variability:Jl.AP.Pettarani exhibits the highest mean concentration(442.5 ppm),likely due to flyover-induced trapping,whereas Jl.Ahmad Yani records the lowest(390.0 ppm).Vertical profiles reveal mid-altitude peaks in street-canyon and industrial settings,and dilution with height in greener areas,indicating ventilation contrasts.Preprocessing removed outliers and applied temperature-humidity corrections to low-cost sensors.Differences across locations and times are statistically significant(p<0.05),and cross-sensor correlations are strong(r≈0.88-0.96)after correction.Compared with fixed ground stations,the system provides fine-scale three-dimensional coverage and real-time visualization useful for field decisions.Limitations include payload-constrained endurance and intermittent data loss in obstructed areas.Findings support targeted interventions,improving canyon ventilation around flyovers and expanding urban greenery relevant to Makassar and similar tropical cities. 展开更多
关键词 CO_(2)Monitoring Drone-Based IoT Urban Air Quality Makassar Spatio-Temporal analysis
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Cavity ring-down spectroscopy CO gas sensor integrating principal component analysis with savitzky-golay filtering
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作者 GUO Zi-long SHI Cheng-rui +4 位作者 DONG Yuan-yuan ZHANG Lei SUN Xiao-yuan SUN Jing-jing ZHOU Sheng 《中国光学(中英文)》 北大核心 2026年第1期179-189,共11页
The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recogni... The Savitzky-Golay(SG)filter,which employs polynomial least-squares approximations to smooth data and estimate derivatives,is widely used for processing noisy data.However,noise suppression by the SG filter is recognized to be limited at data boundaries and high frequencies,which can significantly reduce the signal-to-noise ratio(SNR).To solve this problem,a novel method synergistically integrating Principal Component Analysis(PCA)with SG filtering is proposed in this paper.This approach avoids the is-sue of excessive smoothing associated with larger window sizes.The proposed PCA-SG filtering algorithm was applied to a CO gas sensing system based on Cavity Ring-Down Spectroscopy(CRDS).The perform-ance of the PCA-SG filtering algorithm is demonstrated through comparison with Moving Average Filtering(MAF),Wavelet Transformation(WT),Kalman Filtering(KF),and the SG filter.The results demonstrate that the proposed algorithm exhibits superior noise reduction capabilities compared to the other algorithms evaluated.The SNR of the ring-down signal was improved from 11.8612 dB to 29.0913 dB,and the stand-ard deviation of the extracted ring-down time constant was reduced from 0.037μs to 0.018μs.These results confirm that the proposed PCA-SG filtering algorithm effectively improves the smoothness of the ring-down curve data,demonstrating its feasibility. 展开更多
关键词 cavity ring-down spectroscopy CO gas sensor principal component analysis Savitzky-Golay filter
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Artificial intelligence-assisted non-metallic inclusion particle analysis in advanced steels using machine learning:A review
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作者 Gonghao Lian Xiaoming Liu +3 位作者 Qiang Wang Chunguang Shen Yi Wang Wangzhong Mu 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期401-416,共16页
The detection and characterization of non-metallic inclusions are essential for clean steel production.Recently,imaging analysis combined with high-dimensional data processing of metallic materials using artificial in... The detection and characterization of non-metallic inclusions are essential for clean steel production.Recently,imaging analysis combined with high-dimensional data processing of metallic materials using artificial intelligence(AI)-based machine learning(ML)has developed rapidly.This technique has achieved impressive results in the field of inclusion classification in process metallurgy.The present study surveys the ML modeling of inclusion prediction in advanced steels,including the detection,classification,and feature prediction of inclusions in different steel grades.Studies on clean steel with different features based on data and image analysis via ML are summarized.Regarding the data analysis,the inclusion prediction methodology based on ML establishes a connection between the experimental parameters and inclusion characteristics and analyzes the importance of the experimental parameters.Regarding the image analysis,the focus is placed on the classification of different types of inclusions via deep learning,in comparison with data analysis.Finally,further development of inclusion analyses using ML-based methods is recommended.This work paves the way for the application of AIbased methodologies for ultraclean-steel studies from a sustainable metallurgy perspective. 展开更多
关键词 machine learning inclusion classification image analysis data analysis clean steel
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基于SCSSA-CNN-BiLSTM神经网络的厌氧发酵产气预测
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作者 甄箫斐 焦若楠 +1 位作者 董樾洋 詹寒 《环境工程技术学报》 北大核心 2026年第1期279-289,共11页
厌氧发酵作为一种高效的有机废物处理技术,能够将农业废物转化为沼气,实现资源的循环利用和能源的可持续供应。厌氧发酵过程受到反应底物碳氮比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量等因素的影响。为探究厌氧发酵的规律,进行混... 厌氧发酵作为一种高效的有机废物处理技术,能够将农业废物转化为沼气,实现资源的循环利用和能源的可持续供应。厌氧发酵过程受到反应底物碳氮比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量等因素的影响。为探究厌氧发酵的规律,进行混合原料厌氧发酵产气实验,反应底物中牛粪与玉米秸秆的配比分别为1:1、2:1、3:1,设置3组平行实验,以确保实验结果的可靠性和可重复性。创建了正余弦与柯西变异策略优化的麻雀搜索算法(SCSSA),并将其对卷积双向记忆神经网络(CNNBiLSTM)的超参数进行优化,选择反应时间、牛粪与玉米秸秆配比、pH、挥发性脂肪酸、氨氮浓度以及化学需氧量作为模型的输入参数,日产气量和日甲烷产量作为输出参数。结果表明,牛粪与玉米秸秆配比为3:1时,甲烷产量最多,配比1:1实验组次之,配比2:1实验组最小。基于SCSSA-CNN-BiLSTM混合原料厌氧发酵产气预测模型的日产气量准确率达95.29%,日甲烷产量准确率达95.87%,拟合优度(R^(2))达到了0.972。本研究解决了传统麻雀搜索算法模型易过早收敛导致陷入局部最优的问题,并提高了全局搜索能力,为实际实验提供了依据。 展开更多
关键词 牛粪 玉米秸秆 厌氧发酵 神经网络 麻雀搜索算法 产气预测
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Comprehensive pan-cancer analysis of the receptor-interacting protein kinase family expression,genomic alterations,and functional implications
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作者 Wan-Rong Li Xin Li Jian Wang 《Life Research》 2026年第1期35-44,共10页
Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations... Background:Receptor-interacting protein kinases(RIPKs)regulate cell death,inflammation,and immune responses,yet their roles in cancer are not fully understood.This study investigates the expression,genomic alterations,and functional implications of RIPK family members across various cancers.Methods:We collected multi-omics data from The Cancer Genome Atlas and other public databases,including gene expression,copy number variation(CNV),mutation,methylation,tumor mutation burden(TMB),and microsatellite instability(MSI).Differential expression and survival analyses were performed using DESeq2 and Cox proportional hazards models.CNV and mutation data were analyzed with GISTIC2 and Mutect2,and methylation data with the ChAMP package.Correlations with TMB and MSI were assessed using Pearson coefficients,and gene set enrichment analysis was conducted with the MSigDB Hallmark gene sets.Results:RIPK family members show significant differential expression in various cancers,with RIPK1 and RIPK4 frequently altered.Survival analysis reveals heterogeneous impacts on overall survival.CNV and mutation analyses identify high alteration frequencies for RIPK2 and RIPK7,affecting gene expression.RIPK1 and RIPK7 are hypermethylated in several cancers,inversely correlating with RIPK3 expression.RIPK1,RIPK2,RIPK5,RIPK6,and RIPK7 correlate positively with TMB,while RIPK3 shows negative correlations in some cancers.MSI analysis indicates associations with DNA mismatch repair.G ene set enrichment analysis highlights immune-related pathway enrichment for RIPK1,RIPK2,RIPK3,and RIPK6,and cell proliferation and DNA repair pathways for RIPK4 and RIPK5.RIPK family members showed heterogeneous alterations across cancers:for example,RIPK7 was mutated in up to~15%of u terine c orpus e ndometrial c arcinoma and l ung s quamous c ell c arcinoma cases,and RIPK1 and RIPK7 exhibited frequent promoter hypermethylation in multiple tumor types.Several genes displayed context-dependent associations with overall survival and with TMB/MSI.Conclusion:This pan-cancer analysis of the RIPK family reveals their diverse roles and potential as biomarkers and therapeutic targets.The findings emphasize the importance of RIPK genes in tumorigenesis and suggest context-dependent functions across cancer types.Further studies are needed to explore their mechanisms in cancer development and clinical applications. 展开更多
关键词 RIPK family pan-cancer analysis tumor mutation burden microsatellite instability gene set enrichment analysis
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li Hui Yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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基于VMD-SSA-K-means-iForest的重力坝监测数据异常模式混合识别算法研究
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作者 李铁 李涵曼 +2 位作者 王福生 徐量 郭瑞 《水电能源科学》 北大核心 2026年第1期182-187,共6页
重力坝监测数据的异常识别对大坝安全评估具有重要意义,针对现有方法在模式辨识和特征提取方面的局限性,提出一种基于VMD-SSA-KMeans-iForest的重力坝监测数据异常值混合识别方法,该方法通过引入变分模态分解(VMD)优化SSA分解过程,显著... 重力坝监测数据的异常识别对大坝安全评估具有重要意义,针对现有方法在模式辨识和特征提取方面的局限性,提出一种基于VMD-SSA-KMeans-iForest的重力坝监测数据异常值混合识别方法,该方法通过引入变分模态分解(VMD)优化SSA分解过程,显著提升了特征提取的精度和鲁棒性。在此基础上,构建了基于K-means聚类与孤立森林(iForest)协同的异常识别框架,并将该方法应用于W重力坝异常数据识别中。结果表明,所提方法的异常识别准确率提升了2.5%,同时有效区分了结构损伤与仪器故障引起的异常模式,为重力坝安全评估提供了更可靠的技术支持。 展开更多
关键词 重力坝 奇异谱分析 变分模态分解 K-MEANS聚类 孤立森林 异常模式识别
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Modal analysis on a fluid-conveying pipe subject to elastic supports with unknown-but-bounded parameters
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作者 Sha Wei Xulong Li +2 位作者 Xiong Yan Hu Ding Liqun Chen 《Acta Mechanica Sinica》 2026年第1期310-324,共15页
Uncertain parameters are widespread in engineering systems.This study investigates the modal analysis of a fluid-conveying pipe subjected to elastic supports with unknown-but-bound parameters.The governing equation fo... Uncertain parameters are widespread in engineering systems.This study investigates the modal analysis of a fluid-conveying pipe subjected to elastic supports with unknown-but-bound parameters.The governing equation for the elastically supported fluid-conveying pipe is transformed into ordinary differential equations using the Galerkin truncation method.The Chebyshev interval approach,integrated with the assumed mode method is then used to investigate the effects of uncertainties of support stiffness,fluid speed,and pipe length on the natural frequencies and mode shapes of the pipe.Additionally,both symmetrical and asymmetrical support stiffnesses are discussed.The accuracy and effectiveness of the Chebyshev interval approach are verified through comparison with the Monte Carlo method.The results reveal that,for the same deviation coefficient,uncertainties in symmetrical support stiffness have a greater impact on the first four natural frequencies than those of the asymmetrical one.There may be significant differences in the sensitivity of natural frequencies and mode shapes of the same order to uncertain parameters.Notably,mode shapes susceptible to uncertain parameters exhibit wider fluctuation intervals near the elastic supports,requiring more attention. 展开更多
关键词 Fluid-conveying pipe Elastic support UNCERTAINTY Modal analysis Chebyshev interval method
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Comprehensive quality evaluation and principal component analysis of Crassostrea gigas from North Yellow Sea,China:characterizing nutritional,flavor,and functional profiles
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作者 Shanqin HUO Jixing PENG +3 位作者 Xinnan ZHAO Yichen LIN Xudong LI Zhijun TAN 《Journal of Oceanology and Limnology》 2026年第1期406-418,共13页
Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characte... Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry. 展开更多
关键词 Crassostrea gigas nutritional quality principal component analysis comprehensive evaluation
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Genome-wide characterization and expression analysis of the cultivated peanut AhPR10 gene family mediating resistance to Aspergillus flavus
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作者 Qi Zhao Mengjie Cui +11 位作者 Tengda Guo Lei Shi Feiyan Qi Ziqi Sun Pei Du Hua Liu Yu Zhang Zheng Zheng Bingyan Huang Wenzhao Dong Suoyi Han Xinyou Zhang 《Journal of Integrative Agriculture》 2026年第1期56-67,共12页
The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examinin... The pathogenesis-related protein PR10 plays a vital role in plant growth,development,and stress responses.This study systematically identified and analyzed PR10 genes in cultivated peanut(Arachis hypogaea L.),examining their phylogenetic relationships,conserved motifs,gene structures,and syntenic relationships.The analysis identified 54 Ah PR10 genes,which were classified into eight groups based on phylogenetic relationships,supported by gene structure and conserved motif characterization.Analysis of chromosomal distribution and synteny demonstrated that segmental duplications played a crucial role in the expansion of the Ah PR10 gene family.The identified Ah PR10 genes exhibited both constitutive and inducible expression patterns.Significantly,Ah PR10-7,Ah PR10-33,and Ah PR10-41 demonstrated potential importance in peanut resistance to Aspergillus flavus.In vitro fungistatic experiments demonstrated that recombinant Ah PR10-33 effectively inhibited A.flavus mycelial growth.These findings provide valuable insights for future investigations into Ah PR10 functions in protecting peanut from A.flavus infection. 展开更多
关键词 cultivated peanut PR10 phylogenetic analysis expression pattern Aspergillus avus
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Global research status in the treatment of glaucoma:a systematic bibliometric analysis
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作者 Wen-Hui Liu Chang Shu +1 位作者 Bei-Di Jia Xiao-Rong Li 《International Journal of Ophthalmology(English edition)》 2026年第2期379-392,共14页
AIM:To present an overview of the research on global glaucoma treatment in the last decade in terms of publication year,journals,countries/regions,organizations,references,and keywords,to investigate the current resea... AIM:To present an overview of the research on global glaucoma treatment in the last decade in terms of publication year,journals,countries/regions,organizations,references,and keywords,to investigate the current research international trends and hot topics in this area.METHODS:Bibliometric analysis was conducted on 9128 articles in the Web of Science Core Collection(WoSCC;Clarivate)database.Quantitative and qualitative analysis was employed using VOSviewer(v1.6.18),Pajek(v1.0.0.0),and CiteSpace(v6.1.R2)software.RESULTS:The 9128 papers relating to glaucoma treatment were published from April 2013 to April 2023,of which 7482 articles(82%)were original research articles and 1464(18%)were review articles.The United States(2867)and Johns Hopkins University(166)were the most productive country and institution,respectively,but the University College London had the highest h-index(54).The Journal of Glaucoma was the most productive and Ophthalmology had the highest h-index compared with other journals.The Keywords of interest included treatment surgery,cyclophotocoagulation,minimally invasive glaucoma surgery(MIGS),trabeculectomy,baerveldt,epidemiology,medication adherence,nanoparticle,optical coherence tomography(OCT),gene therapy,and artificial intelligence(AI).Glaucoma surgery appeared as a current research hotspot through the analysis of keywords.CONCLUSION:This study provides insights into the research trends and potential research hotspots in the treatment of glaucoma.This will help researchers to evaluate research policies and to promote international cooperation. 展开更多
关键词 glaucoma treatment bibliometric analysis SURGERY minimally invasive glaucoma surgery NANOPARTICLE
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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A conceptual analysis of reflective supervision for creating a positive intensive care practice environment
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作者 Mpho Grace Chipu 《International Journal of Nursing Sciences》 2026年第1期88-95,共8页
Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant... Objectives This study aimed to explore and clarify the concept of reflective supervision as a professional self-care strategy to create a positive Intensive Care Unit(ICU)practice environment.Methods Walker and Avant’s eight-step concept analysis approach was utilized to identify and define the attributes,antecedents,and consequences of reflective supervision in the ICU.An extensive literature search was conducted across various databases,including Google Scholar,CINAHL,PubMed.Articles published from 2005 to 2025 were identified.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020 statement to indicate the included articles and extract related data based on relevance.Results Forty articles were included in the analysis.The identified attributes included the supervisor-supervisee relationship,effective communication,teamwork,collaborations,reflection,competencies,feedback,continuous support,and autonomous choice.The identified antecedents included participation,supportive supervision,flexibility,open-door policy,training,and motivation.Consequences impacting the success of reflective supervision were identified as promotion of resiliency,autonomy,work-life balance,self-awareness,increased self-esteem,professional development,critical thinking,increased job satisfaction,and enhanced commitment.Conclusions Reflective supervision is a complex professional self-care strategy that enhances ICU practice,by promoting nurses’well-being,self-awareness,therapeutic skills,and professional development. 展开更多
关键词 Concept analysis Intensive Care Unit NURSING Positive environment Reflective supervision
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Sensitivity analysis of rod rearrangement in criticality safety for PWR fuel assemblies under transportation accidents
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作者 Xin‑Ling Dai De‑Chang Cai +1 位作者 Yan‑Min Zhang Jin Cai 《Nuclear Science and Techniques》 2026年第1期263-282,共20页
To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains i... To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains in a subcritical state during routine,normal,and accidental transport conditions.In the event of an accident,the rods within the storage tank may become rearranged,introducing uncertainty that must be accounted for to ensure that criticality analysis results are conservative.Historically,this uncertainty was addressed overly conservatively due to limited research on non-uniform arrangement scenarios,which proved unsuitable for criticality safety analysis of spent fuel packages.This paper introduced three distinct methods to non-uniformly rearrange fuel rods—Uniform Arrangement by Blocks,Layer-by-Layer Determination,and Birdcage Deformation—and meticulously evaluates the influences of rod rearrangement on the effective multiplication factor of neutrons,k eff,utilizing the Monte Carlo method.Ultimately,this study presents a holistic method capable of encompassing the entire spectrum of potential effects stemming from the rearrangement of fuel rods during rods mispositioning accident.By augmenting the safety margin,this approach proves to be adeptly suited for the criticality safety analysis of nuclear fuel transport containers. 展开更多
关键词 Criticality safety analysis Fuel transports Rods mispositioning accident Non-uniform arrangement
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