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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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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:1
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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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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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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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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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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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Heavy metal risks and policy analysis on using industrial waste salts for making value-added snow-melting agents
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作者 Yubiao Ma Jiaxin Yin +2 位作者 Yunfei Wang Lei Wang Jianxin Zhu 《Journal of Environmental Sciences》 2026年第1期756-766,共11页
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po... Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management. 展开更多
关键词 Snow-melting agent Heavy metals Industrial waste salts recycled Comparative analysis
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Evaluation of the protective effects of Crocus sativus L.against cypermethrin induced reproductive toxicity in male rats through the Nrf2 pathway and in silico ADMET analysis
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作者 Fareena Tariq Farah Ijaz +9 位作者 Yasameen Hameed Jasim Farah Naz Channa Sohail Ahmed Ahmed Shandookh Hameed Sobia Alyas Ahmed Raheem Rayshan Tahira Bibi Nazima Yousaf Khan Sadia Bibi Jameel Ahmed Buzdar 《Traditional Medicine Research》 2026年第3期12-25,共14页
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i... Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice. 展开更多
关键词 Crocus sativus L. CYPERMETHRIN male reproductive toxicity Nrf2 pathway in silico ADMET analysis
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Cloning,Sequencing and Molecular Phylogenetic Analysis of the Mitochondrial Cytochrome Oxidase Ⅰ Gene of Chilo suppressalis 被引量:1
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作者 汪爱民 洪桂云 魏兆军 《Agricultural Science & Technology》 CAS 2011年第5期674-677,共4页
[Objective] The research aimed at cloning and analyzing mitochondrial cytochrome oxidase I gene(cox 1)of C.suppressalis.[Method] The mitochondrial cox 1 gene of C.suppressalis was cloned with PCR method and sequence... [Objective] The research aimed at cloning and analyzing mitochondrial cytochrome oxidase I gene(cox 1)of C.suppressalis.[Method] The mitochondrial cox 1 gene of C.suppressalis was cloned with PCR method and sequenced.Then,cox1 sequences of other 21 Lepidopteran species were obtained by blasting the GenBank with cox 1 gene sequence of C.suppressalis.Finally,homology comparison and molecular phylogenitic analysis among the 22 Lepidopteran species were conducted.[Result] The open reading frame of cox 1 gene from C.suppressalis contained 1 531 nucleotides encoding a putative protein of 510 amino acids.The cox1 gene used a start codon CGA,and an incomplete termination codon composed of only T.Based on the amino acid sequences of cox 1,the molecular phylogenetic tree of Lepidoptera was reconstructed using the maximum likelihood(ML)method.The molecular phylogenetic tree was similar to the morphological phylogenetic tree mainly,but also showed some differences.[Conclusion] The result will provide reference for further research on expression and application of cox 1 gene. 展开更多
关键词 Mitochondrial DNA Chilo suppressalis cox 1 gene Phylogenetic analysis
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基于SSA-ELM神经网络的室内可见光定位系统 被引量:1
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作者 贾科军 牛振 +3 位作者 于凯 张志聪 彭铎 曹明华 《光通信研究》 北大核心 2025年第1期13-17,共5页
【目的】针对极限学习机(ELM)神经网络在室内可见光定位(VLP)中收敛不稳定,易陷入局部最优状态,导致定位精度降低的问题,文章引入了麻雀搜索算法(SSA)确定ELM神经网络的初始权值和阈值,提出了SSA-ELM神经网络算法。【方法】首先,采集定... 【目的】针对极限学习机(ELM)神经网络在室内可见光定位(VLP)中收敛不稳定,易陷入局部最优状态,导致定位精度降低的问题,文章引入了麻雀搜索算法(SSA)确定ELM神经网络的初始权值和阈值,提出了SSA-ELM神经网络算法。【方法】首先,采集定位区域内接收信号强度(RSS)与位置信息作为指纹数据;然后,训练SSA-ELM神经网络并得到预测模型,将测试集数据输入预测模型得到待测位置的定位结果;最后,设计了仿真实验和测试平台。【结果】仿真表明,在立体空间模型中0、0.3、0.6和0.9 m 4个接收高度,平均误差分别为1.73、1.86、2.18和3.47 cm,与反向传播(BP)、SSA-BP和ELM定位算法相比,SSA-ELM神经网络算法定位精度分别提高了83.55%、45.71%和26.26%,定位时间分别降低了36.48%、17.69%和6.61%。实验测试表明,文章所提SSA-ELM神经网络算法的平均定位误差为3.75 cm,比未优化的ELM神经网络定位精度提高了16.38%。【结论】SSA对ELM神经网络具有明显的优化作用,能够显著降低定位误差,减少定位时间。 展开更多
关键词 可见光通信 室内定位 极限学习机神经网络 麻雀搜索算法
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基于SSA-VMD-LSTM的架空输电线路动态载流量预测方法
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作者 王帅 申杰文 +1 位作者 徐彬 朱振东 《电子测量技术》 北大核心 2025年第19期115-125,共11页
准确预测架空输电线路动态载流量是保障线路安全增容的关键。针对传统预测模型因依赖人工经验选择模型超参数,难以有效降低线路动态载流量波动性而导致的预测精度不佳问题,本研究创新性提出一种基于SSA-VMD-LSTM的预测方法。该方法深度... 准确预测架空输电线路动态载流量是保障线路安全增容的关键。针对传统预测模型因依赖人工经验选择模型超参数,难以有效降低线路动态载流量波动性而导致的预测精度不佳问题,本研究创新性提出一种基于SSA-VMD-LSTM的预测方法。该方法深度融合了SSA的全局优化能力、VMD的多尺度数据分解特性以及LSTM的时序建模优势,构建了一个层次化的人工智能预测模型。首先,利用SSA的强大搜索能力对VMD超参数进行迭代寻优,获取最优超参数;随后,采用VMD对线路动态载流量进行多尺度分解,得到一系列中心频率不同但局部平稳的分量;在此基础上,对多个分量分别建立LSTM进行预测;最后,将分量预测结果叠加得到最终预测结果。实验结果表明,与多个传统预测模型相比,所提方法的预测精度至少提升4.78%,充分验证了该方法在动态载流量预测中的有效性和优越性。 展开更多
关键词 架空输电线路 动态载流量 ssa VMD 超参数寻优
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基于ISSA-XGBoost的数字孪生变电站故障监测
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作者 何锐 梁智 +2 位作者 戈一航 凌行龙 王应宇 《科技和产业》 2025年第17期100-107,共8页
随着智能电网的快速发展,传统变电站的监控方式已难以满足现代电网对高效、准确监控的需求。针对传统变电站监控信息准确率较低的问题,提出基于ISSA-XGBoost(改进麻雀搜索算法-极端梯度提升树)的数字孪生变电站故障监测。首先基于八叉... 随着智能电网的快速发展,传统变电站的监控方式已难以满足现代电网对高效、准确监控的需求。针对传统变电站监控信息准确率较低的问题,提出基于ISSA-XGBoost(改进麻雀搜索算法-极端梯度提升树)的数字孪生变电站故障监测。首先基于八叉树空间分割和NURBS(非均匀有理B样条)三维数字孪生(DT)体建模技术,建立数字孪生变电站模型。通过主成分分析提取关键数据特征,降低数据集的复杂性。结合变电站的运行模式,建立XGBoost的状态监测模型,通过改进的麻雀搜索算法寻找XGBoost的超参数,弥补传统XGBoost人工设定超参数的不足。变电站状态监测正确率达到96.45%,相较传统XGBoost监测正确率提高了8.11%,训练时间缩短了4.8%,ISSA-XGBoost模型故障监测精度更高、速度更快。实践表明,该方法能够更精确地对变电站电气设备的故障进行监测。 展开更多
关键词 变电站 数字孪生(DT) 主成分分析(PCA) 麻雀搜索算法(ssa) 极端梯度提升树(XGBoost)
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基于SQL Server Analysis Service(SSAS)的土地地类关系空间数据挖掘 被引量:1
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作者 任沂军 刘玲玲 +1 位作者 邹艳红 陈佳音 《城市勘测》 2014年第6期35-39,共5页
基于SQL Server Analysis Services(简称SSAS)提供的Microsoft关联规则挖掘算法和事务数据挖掘功能,通过利用Arc GIS软件、空间数据库引擎Arc SDE和数据库SQL Server软件,提出了一种新的土地地类关系挖掘实现方案。首先结合空间数据挖掘... 基于SQL Server Analysis Services(简称SSAS)提供的Microsoft关联规则挖掘算法和事务数据挖掘功能,通过利用Arc GIS软件、空间数据库引擎Arc SDE和数据库SQL Server软件,提出了一种新的土地地类关系挖掘实现方案。首先结合空间数据挖掘(Spatial Data Mining,SDM)相关技术方法,以土地利用数据库为基础,实现空间数据提取;然后通过空间关联操作将空间信息转化为事务,最后在SSAS中创建多维数据集,完成相关数据挖掘任务。基于某市实例土地利用数据库,采用该方法探测相邻地类间的隐含关系,通过建立相邻地类图斑空间关联规则挖掘模型,设置不同的参数,得到了一系列比较实用合理的关联规则,通过实践证明了这种方案的有效性。 展开更多
关键词 土地地类关系 SQL Server analysis Service(ssaS) 空间数据挖掘 关联规则算法
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基于CNN-BiLSTM-SSA的锅炉再热器壁温预测模型
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作者 徐世明 何至谦 +6 位作者 彭献永 商忠宝 范景玮 王俊略 曲舒杨 刘洋 周怀春 《动力工程学报》 北大核心 2026年第1期121-130,共10页
针对锅炉高温再热器壁温动态特点,提出了一种基于稀疏自注意力(SSA)、卷积神经网络(CNN)及双向长短期记忆神经网络(BiLSTM)相融合的再热器壁温软测量模型。首先,采用核主成分分析(KPCA)算法对原始候选变量进行筛选降维,选择前26个主成... 针对锅炉高温再热器壁温动态特点,提出了一种基于稀疏自注意力(SSA)、卷积神经网络(CNN)及双向长短期记忆神经网络(BiLSTM)相融合的再热器壁温软测量模型。首先,采用核主成分分析(KPCA)算法对原始候选变量进行筛选降维,选择前26个主成分变量作为模型的最终输入。其次,考虑利用CNN捕捉局部相关性,BiLSTM学习数据的长期序列依赖性的优势,使用卷积神经网络-双向长短期记忆神经网络(CNN-BiLSTM)捕捉时序数据中的短期和长期依赖关系,引入稀疏自注意力SSA机制,通过为不同特征部分分配自适应权重,从而增强CNN-BiLSTM模型的特征提取与建模能力,最后利用在役1000 MW超超临界锅炉的历史数据进行仿真实验。结果表明:CNN-BiLSTM-SSA模型在高温再热器壁温预测中的均方根误差(RMSE)、平均绝对误差(MAE)及平均绝对百分比误差(MAPE)分别为4.92℃、3.81℃和0.6241%,相应的指标均优于CNN、LSTM、BiLSTM、CNN-LSTM和CNN-BiLSTM模型。 展开更多
关键词 再热器壁温软测量 深度学习 卷积神经网络 长短期记忆网络 注意力机制 核主成分分析 CNN-BiLSTM
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基于BP-SSA算法的大学生体质健康水平评价模型研究
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作者 赵莹 《合肥师范学院学报》 2025年第5期171-174,180,共5页
随着经济和社会的不断发展,大学生体质的培养受到了广泛的关注。然而,传统的身体素质评价方法存在一些不足,如评价指标单一,评价结果不准确等。针对这一问题,研究提出利用误差反向传播算法与麻雀搜索算法,构建一种大学生体质健康水平评... 随着经济和社会的不断发展,大学生体质的培养受到了广泛的关注。然而,传统的身体素质评价方法存在一些不足,如评价指标单一,评价结果不准确等。针对这一问题,研究提出利用误差反向传播算法与麻雀搜索算法,构建一种大学生体质健康水平评价模型。经过对比试验,结果表明,该算法的准确率最高可达到96%,优于对比算法。研究提出的大学生体质健康水平评价模型的F值与G值分别为86%、92%,优于对比模型。综上,研究提出的基于改进麻雀算法的大学生体质健康水平评价模型,能够有效地提高我国大学生体质健康评估的准确率和工作效率。 展开更多
关键词 BP算法 ssa算法 大学生体质 评价模型
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SSA-XGBoost模型的资源型城市热环境非线性影响因素分析
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作者 范强 刘凯泽 张兵 《测绘科学》 北大核心 2025年第8期80-91,共12页
针对资源型城市热环境成因机制的复杂性以及高温挑战日益加剧问题,该文选择4个典型资源型城市为研究区,选取自然因素和人文因素作为影响因子,构建了基于麻雀搜索算法(SSA)优化的XGBoost回归模型,并结合SHAP解释机制量化各驱动因子对城... 针对资源型城市热环境成因机制的复杂性以及高温挑战日益加剧问题,该文选择4个典型资源型城市为研究区,选取自然因素和人文因素作为影响因子,构建了基于麻雀搜索算法(SSA)优化的XGBoost回归模型,并结合SHAP解释机制量化各驱动因子对城市热环境的影响。研究发现,所选因子对热环境的作用效果和贡献程度因城市的阶段性发展特征存在显著差异,这与城市化过程中地表覆被类型的空间差异具有密切关联;SHAP可解释性分析进一步揭示了各变量对热环境的具体影响,展现了模型在解释变量作用机制上的可靠性和透明性;SSA能够有效的对模型进行优化,构建的SSA-XGBoost模型的R^(2)均在0.9以上,表现出良好的稳定性和回归能力。该模型更精确地分析了资源型城市热环境非线性因素影响,为典型资源城市的建设和管理提供参考。 展开更多
关键词 热环境 地表温度 ssa-XGBoost 资源型城市 非线性回归 SHAP可解释
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基于CNN-SSA-GRU的位置指纹定位方法研究
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作者 吴兰 胡家傲 《计算机仿真》 2025年第1期323-328,366,共7页
针对现有位置指纹定位方法不能充分利用指纹数据中的特征信息以及训练过程中关键参数需要人为确定导致定位精度不高的问题,利用卷积神经网络(CNN)提取指纹数据中的空间特征信息并构造成特征向量,再利用门控循环神经网络(GRU)提取特征向... 针对现有位置指纹定位方法不能充分利用指纹数据中的特征信息以及训练过程中关键参数需要人为确定导致定位精度不高的问题,利用卷积神经网络(CNN)提取指纹数据中的空间特征信息并构造成特征向量,再利用门控循环神经网络(GRU)提取特征向量中的时间特征,建立特征融合的位置指纹定位模型进行定位,以提高定位精度。同时利用麻雀搜索算法(SSA)对GRU网络训练过程中的关键参数进行最佳寻优,降低人为设置训练参数对模型定位效果的影响,进一步提高模型的定位精度。实验分析表明,提出的CNN-SSA-GRU指纹定位方法平均误差在1.351m,与传统指纹定位方法相比定位精度更高,能够满足实际定位需求。 展开更多
关键词 指纹定位 卷积神经网络 麻雀搜索算法 门控循环神经网络
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Global sensitivity analysis of wheat grain yield and quality and the related process variables from the DSSAT-CERES model based on the extended Fourier Amplitude Sensitivity Test method 被引量:11
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作者 LI Zhen-hai JIN Xiu-liang +2 位作者 LIU Hai-long XU Xin-gang WANG Ji-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第7期1547-1561,共15页
A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A maj... A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A major challenge of model application is the optimization and calibration of a considerable number of parameters.Sensitivity analysis(SA) has become an effective method to identify the importance of various parameters.In this study,the extended Fourier Amplitude Sensitivity Test(EFAST) approach was used to evaluate the sensitivity of the DSSAT-CERES model output responses of interest to 39 crop genotype parameters and six soil parameters.The outputs for the SA included grain yield and quality(take grain protein content(GPC) as an indicator) at maturity stage,as well as leaf area index,aboveground biomass,and aboveground nitrogen accumulation at the critical process variables.The key results showed that:(1) the influence of parameter bounds on the sensitivity results was slight and less than the impacts from the significance of the parameters themselves;(2) the sensitivity parameters of grain yield and GPC were different,and the sensitivity of the interactions between parameters to GPC was greater than those between the parameters to grain yield;and(3) the sensitivity analyses of some process variables,including leaf area index,aboveground biomass,and aboveground nitrogen accumulation,should be performed differently.Finally,some parameters,which improve the model’s structure and the accuracy of the process simulation,should not be ignored when maturity output as an objective variable is studied. 展开更多
关键词 global sensitivity analysis DssaT EFAST wheat yield GRAIN protein content
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