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Scenario-based modeling and driver analysis of ecological resilience:A framework study in the Qinling-Daba Mountains 认领 引用
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作者 LI Siqi LI Kang +6 位作者 QIAN Hui GAO Yanyan CHEN Jie WU Puxia MA Yandong HE Yi LIU Zhao 《Journal of Geographical Sciences》 SCIE CSCD 2026年第7期1701-1730,共30页
Ecological resilience(ER)reflects an ecosystem's capacity to adapt to climate change,natural disturbances,and human-induced stress.This study evaluated ER in the Qinling-Daba Mountains(QDM),China,from 2000 to 2020... Ecological resilience(ER)reflects an ecosystem's capacity to adapt to climate change,natural disturbances,and human-induced stress.This study evaluated ER in the Qinling-Daba Mountains(QDM),China,from 2000 to 2020 using a resistance-robustnessrecovery model.Specifically,the PLUS model was employed to assess the impacts of land use change on ER under three scenarios:natural development(NDS),ecological preservation(EPS),and farmland preservation(FPS).Spatial drivers of ER were analyzed using the geographic detector model and multi-scale geographically weighted regression.The results revealed a significant upward trend in ER,with high values in central and southern QDM and low values in urban lowland areas.Regarding the scenarios,ER improved under EPS,plateaued under NDS,and declined under FPS.The key drivers were found to be NDVI,slope,DEM,temperature,and nighttime light.ER showed positive correlations with high NDVI and slope and negative correlations with low vegetation and flat terrain.These findings provide deeper insight into ER dynamics and scientific guidance for regional ecological protection,planning,and resilience building in the QDM and similar mountainous ecosystems globally. 展开更多
关键词 ecological resilience resistance-robustness-recovery PLUS model driving factors
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Integrated ATAC-seq and mRNA-seq analyses on granulosa cells identify key regulators of follicle selection in chickens 认领 引用
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作者 Dandan Li Chao Qi +3 位作者 Yi Sun Li Kang Qingqing Wei Yunliang Jiang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2026年第4期1975-1991,共17页
Background The differences in egg production performance among hens are closely linked to the efficiency of follicle selection,which is characterized by granulosa cell differentiation and progesterone production.In th... Background The differences in egg production performance among hens are closely linked to the efficiency of follicle selection,which is characterized by granulosa cell differentiation and progesterone production.In this study,by integrating ATAC-seq and mRNA-seq analyses on granulosa cells from pre-hierarchical(Pre-GCs)and hierarchical(Post-GCs)follicles,we set out to identify key regulatory factors involved in chicken follicle selection.Results ATAC-seq analysis revealed 21,616 upregulated and 6,344 downregulated differentially accessible peaks in Post-GCs compared to Pre-GCs.Enrichment analysis of the top 400 upregulated and downregulated peaks(ranked by|log2FC|)identified 106 upregulated and 81 downregulated genes encoding transcription factors(TFs).mRNA-seq analysis showed 1,337 upregulated and 2,282 downregulated differentially expressed genes in Post-GCs compared to Pre-GCs.Among these,146 genes were uniquely expressed in Pre-GCs,and 40 genes were uniquely expressed in Post-GCs.Integrated ATAC-seq and mRNA-seq analyses revealed that chromatin accessibility and gene expression were not always positively correlated.Additionally,four significantly upregulated core TFs(CREM,ESRRB,NR5A1,GATA6)and one significantly downregulated TF(ETS1)genes were identified.The upregulated TFs were associated with 651significantly upregulated target genes across both mRNA and ATAC-seq data,while the downregulated TFs were associated with 236 significantly downregulated target genes.KEGG enrichment of these target genes identified core genes enriched in pathways closely related to follicle selection,such as Wnt signaling pathway.In the protein-protein interaction(PPI)network of core upregulated target genes,genes such as SMAD2 and PPARA occupied central positions,while genes such as LEF1 and RAC2 were central in the PPI network of core downregulated target genes.Among these core TFs,GATA6 is confirmed to promote the expression of key cholesterol and progesterone synthesis genes to enhance both cholesterol and progesterone production,with follicle-stimulating hormone further amplifying its effect on progesterone synthesis.Conclusions Our integrated ATAC-seq and mRNA-seq analyses define key epigenetic and transcriptional changes during chicken follicle selection.We highlight core transcription factors,including CREM,ESRRB,NR5A1,GATA6and ETS1,and their stage-specific target networks.Functional assays show that GATA6 promotes cholesterol and progesterone synthesis,providing mechanistic insight and candidate targets for improving hen reproductive performance. 展开更多
关键词 ATAC-seq Chicken Follicle selection Granulosa cell mRNA-seq
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Carbonated water erosion characteristics and mechanism of tunnel lining cement-based materials in karst environment 认领 引用 被引量：1
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作者 ZOU Min LIU Juan-hong LI Kang 《Journal of Central South University》 SCIE EI CAS CSCD 2025年第8期3015-3034,共20页
The study aims to investigate the carbonated water erosion mechanism of lining concrete in tunnels traversing karst environment and enhance its resistance.In this study,dynamic carbonated water erosion was simulated t... The study aims to investigate the carbonated water erosion mechanism of lining concrete in tunnels traversing karst environment and enhance its resistance.In this study,dynamic carbonated water erosion was simulated to assess erosion depth,microstructure,phase migrations,and pore structure in various tunnel lining cement-based materials.Additionally,Ca2+leaching was analyzed,and impact of Ca/Si molar ratio in hydration products on erosion resistance was discussed by thermodynamic calculations.The results indicate that carbonated water erosion caused rough and porous surface on specimens,with reduced portlandite and CaCO3 content,increased porosity,and an enlargement of pore size.The thermodynamic calculations indicate that the erosion is spontaneous,driven by physical dissolution and chemical reactions dominated by Gibbs free energy.And the erosion reactions proceed more spontaneously and extensively when Ca/Si molar ratio in hydration products was higher.Therefore,cement-based materials with higher portlandite content exhibit weaker erosion resistance.Model-building concrete,with C-S-H gel and portlandite as primary hydration products,has greater erosion susceptibility than shotcrete with ettringite as main hydration product.Moreover,adding silicon-rich mineral admixtures can enhance the erosion resistance.This research offers theory and tech insights to boost cement-based material resistance against carbonated water erosion in karst tunnel engineering. 展开更多
关键词 tunnel lining cement-based materials carbonated water erosion phase analysis pore structure Ca/Si molar ratio
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Study on the correlation between insomnia degree and quality of life in psychiatric outpatients in Chifeng city 认领 引用 被引量：1
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作者 Meng-Ran Xie Gang Li +6 位作者 Yu-Ting Shi Li Kang Na-Na Dou Bing Liu Jia-Li Cao Shi-Qi Fu Shi-Guang Hao 《World Journal of Psychiatry》 SCIE 2025年第5期136-144,共9页
BACKGROUND Insomnia is a common sleep disorder that negatively impacts quality of life and is frequently comorbid with depression and anxiety.Chronic insomnia affects approximately 15%of the global population,with hig... BACKGROUND Insomnia is a common sleep disorder that negatively impacts quality of life and is frequently comorbid with depression and anxiety.Chronic insomnia affects approximately 15%of the global population,with higher prevalence among females and the elderly.While existing research suggests a bidirectional relationship between insomnia and emotional disorders,the specific impact of insomnia severity on depression,anxiety,and quality of life remains unclear.This study investigates the correlation between insomnia severity and these factors in psychiatric outpatients,hypothesizing that greater insomnia severity is associated with higher levels of depression and anxiety,as well as poorer quality of life.AIM To explore the correlation between insomnia severity and depression,anxiety,and quality of life in primary chronic insomnia patients.METHODS From June to December 2023,345 patients with primary insomnia in Chifeng city were recruited and divided into three groups based on Pittsburgh sleep quality index(PSQI)scores:Mild(n=137),moderate(n=162),and severe(n=46).Demographic data were collected via questionnaires.Self-rating depression scale(SDS),self-rating anxiety scale(SAS),PSQI,and short form 36(SF-36)scores were compared,and Pearson and partial correlation analyses were performed.RESULTS The greater the degree of insomnia,the greater the symptoms of depression and anxiety(P<0.001).The more severe the insomnia,the lower the SF-36 score(excluding body pain),and the difference between the three groups was statist ically significant(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SDS score and SAS score were apparently positively correlated with the severity of insomnia(P<0.001).Pearson correlation analysis and partial correlation analysis depicted the SF-36 scores were apparently positively correlated with the severity of insomnia(P<0.05).CONCLUSION Depression and anxiety are independent factors influencing insomnia severity in primary chronic insomnia patients.Higher depression/anxiety levels correlate with worse insomnia,impacting quality of life. 展开更多
关键词 Insomnia severity Life quality Depression Anxiety Psychiatric outpatients Correlation analysis
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Micro-arc oxidation coatings on Mg-Li alloys 认领 引用 被引量：13
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作者 Xu Yongjun Li Kang +2 位作者 Yao Zhongping Jiang Zhaohua Zhang Milin 《Rare Metals》 SCIE EI CAS 2009年第2期160-163,共4页
Micro-arc oxidation (MAO) method was used for the surface modification of an Mg-5wt.%Li alloy. Ceramic coatings were in-situ fabricated on the Mg-Li alloy. The morphology feature,phase composition,and corrosion-resist... Micro-arc oxidation (MAO) method was used for the surface modification of an Mg-5wt.%Li alloy. Ceramic coatings were in-situ fabricated on the Mg-Li alloy. The morphology feature,phase composition,and corrosion-resistance of the formed ceramic coatings were studied by SEM,XRD,and electrochemical methods,respectively. The results showed that the coatings produced in a sodium silicate solution system were composed of MgO and Mg2SiO4. The ceramic coating became thicker and the content of Mg2SiO4 phase increase... 展开更多
关键词 Mg-Li alloys ceramic coatings micro-arc oxidation corrosion resistance
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The precipitation evolution and mechanical properties of an Al-Cu-Li-Mg alloy during natural aging 认领 引用 被引量：7
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作者 San-xi Deng Zhen-zhen Liu +7 位作者 Guang-jun Zeng Hui Xiang Peng-cheng Ma Jia-ming Yin Li Kang Si-han Wen Jin-feng Li Dan-yang Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第25期42-53,共12页
The precipitation evolution and mechanical properties of a commercial Al-Cu-Li-Mg alloy in natural aging(NA)tempers(T3 and T4)were investigated in detail.It was demonstrated that GPI zones were the pre-dominant precip... The precipitation evolution and mechanical properties of a commercial Al-Cu-Li-Mg alloy in natural aging(NA)tempers(T3 and T4)were investigated in detail.It was demonstrated that GPI zones were the pre-dominant precipitate throughout the NA process.In the T3-aged sample,the precipitation sequence was determined:supersaturated solid solution(SSSS)→atom clusters→GPI zones,whereas in the T4-aged sample,it was SSSS→atom clusters→GPI zones→GPI zones+δ/GPI zones/δ.For samples without NA,the strength of the T3 sample was 76.0 MPa higher than that in the T4 sample,which was attributed to the pre-deformation-introduced dislocations.During the early stage of NA,GPI zone nucleation was substantially restricted in the T3 sample,resulting in a much lower number density of GPI zones.It re-tarded the aging response and strength improvement,consequently narrowing the strength difference between T3 and T4 samples.As the NA process progressed,the average diameter of GPI zones in the T4 sample increased to approximately 4.5 nm,accompanied by the formation ofδ/GPI zones/δcomposite precipitate.However,GPI zone growth andδ/GPI zones/δcomposite precipitate formation were signifi-cantly inhibited in the T3 sample,as evidenced by its much smaller average diameter of approximately 2.1 nm and the absence of composite precipitates.It inhibited the strength improvement of the T3 sam-ple.Therefore,after a long period(5 months)of NA,the strength of the T4 sample was about 13.0 MPa higher than that of the T3 samples,instead. 展开更多
关键词 Al-Cu-Li-Mg alloy Precipitation evolution Mechanical properties Natrual aging HAADF-STEM
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Programmed Death Ligand-1 on Microglia Regulates Th1 Differentiation via Nitric Oxide in Experimental Autoimmune Encephalomyelitis 认领 引用 被引量：10
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作者 Jingxia Hu Hao He +7 位作者 Zhengang Yang Guangming Zhu Li Kang Xiuli Jing Hai Lu Wengang Song Bo Bai Hua Tang 《Neuroscience Bulletin》 SCIE CAS CSCD 2016年第1期70-82,共13页
Microglia are considered to be potential anti- gen-presenting cells and have the ability to present antigen under pathological conditions. Nevertheless, whether and how microglia are involved in immune regulation are ... Microglia are considered to be potential anti- gen-presenting cells and have the ability to present antigen under pathological conditions. Nevertheless, whether and how microglia are involved in immune regulation are lar- gely unknown. Here, we investigated the suppressive activity of microglia during experimental autoimmune encephalomyelitis （EAE） induced by myelin oligodendro- cyte glycoprotein, with the goal of understanding their role in regulating the T cell reaction. Using flow cytometric analysis, we found that microglia were characterized by increased cell number and up-regulated programmed death ligand-1 （PD-L1） at the peak phase of EAE. Meanwhile, both the CD4＋ T cells and microglia that infiltrated the central nervous system expressed higher levels of PD1, the receptor for PD-L1, accompanied by a decline of Thl cells. In an ex vivo co-culture system, microglia from EAE mice inhibited the proliferation of antigen-specific CD4＋ T cells and the differentiation of Thl cells, and this was significantly inhibited by PD-L 1 blockade. Further, microglia suppressed Thl cells via nitric oxide （NO）, the production of which was dependent on PD-L1. Thus, these data suggest a scenario in which microglia are involved in the regulation of EAE by suppressing Thl-cell differenti- ation via the PD-L1-NO pathway. 展开更多
关键词 Microglia Negative immune regulation PD-L1 Nitric oxide - EAE
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Key technologies for salt-cavern underground gas storage construction and evaluation and their application 认领 引用 被引量：5
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作者 Wanyan Qiqi Ding Guosheng +3 位作者 Zhao Yan Li Kang Deng Jingen Zheng Yali 《Natural Gas Industry B》 2018年第6期623-630,共8页
Salt-cavern underground gas storage is technically faced with non-uniform distribution of stratified salt rocks,complex solution mining mechanism,difficult control of solution mining process,less operation safety and ... Salt-cavern underground gas storage is technically faced with non-uniform distribution of stratified salt rocks,complex solution mining mechanism,difficult control of solution mining process,less operation safety and stability of caverns and difficult reconstruction and utilization of old caverns.In view of these technical difficulties,the design concept was fully updated based on the design experience and field practice of Jintan gas storage in Jiangsu,for purpose of maximizing salt layer utilization ratio,improving solution mining efficiency,shortening construction time and ensuring cavity safety.Based on the updated design concept,five series of key technologies were proposed in site evaluation,cavern design and control,stability assessment and storage capacity parameter design,old cavern screening and utilization,and gas storage operation and monitoring.The following results were obtained from the actual application of these key technologies to the Jintan gas storage.First,the actual drilling coincidence rate of geological program is high.Second,the cavern is morphologically coincident with the design.Third,the cavern deformation retract rate is in line with the stability evaluation result.Fourth,old caverns are successfully reconstructed and utilized.Fifth,the arrangement of the monitoring network ensures the operation safety of salt-cavern underground gas storage and makes an important contribution to the peak shaving and supply guarantee of natural gas in the Yangtze River Delta region.In conclusion,the research results provide guidance for the design and engineering implementation of salt-cavern underground gas storage construction program,as well as a theoretical and technical support for the construction of similar gas storages. 展开更多
关键词 Salt-cavern underground gas storage Gas storage building technology Site evaluation Solution mining Leaching control Stability evaluation Old cavern utilization Monitoring network Jintan gas storage
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Interaction mechanism between arsenate and fayalite-type copper slag at high temperatures 认领 引用 被引量：4
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作者 Da-wei WANG Zong-wen ZHAO +3 位作者 Zhang LIN Yan-jie LIANG Li KANG Bing PENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期709-720,共12页
The interaction mechanism between sodium arsenate and fayalite-type copper slag at 1200℃was investigated through XRD,XPS,HRTEM,TCLP and other technical means and methods.The results indicated that the proportions of ... The interaction mechanism between sodium arsenate and fayalite-type copper slag at 1200℃was investigated through XRD,XPS,HRTEM,TCLP and other technical means and methods.The results indicated that the proportions of sodium arsenate in the slag and flue gas phases were approximately 30%and 70%,respectively.The addition of sodium arsenate depolymerized the fayalite structure and changed it from a crystalline state to an amorphous state.The fayalite structural changes indicated that the[AsO4]tetrahedron in sodium arsenate combined with the[SiO4]tetrahedron and[FeO4]tetrahedron through bridging oxygen to form a silicate glass structure.The TCLP test results of the samples before and after the high temperature reaction of fayalite and sodium arsenate showed that after high temperature reaction,fayalite could effectively reduce the leaching toxicity of sodium arsenate,reducing the leaching concentration of arsenic from 3025.52 to 12.8 mg/L before and after reaction,respectively. 展开更多
关键词 fayalite sodium arsenate depolymerization reaction silicate glass structure
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Distribution of Equilibrium Free Energies in a Thermodynamic System with Broken Ergodicity 认领 引用 被引量：1
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作者 ZHOU Hai-Jun LI Kang 《Communications in Theoretical Physics》 SCIE CAS 2008年第3期659-664,共6页
At low temperatures the configurational phase space of a macroscopic complex system(e.g.,a spin-glass)of N-10^23 interacting particles may split into an exponential numberΩs-exp(const×N)of ergodic sub-spaces(the... At low temperatures the configurational phase space of a macroscopic complex system(e.g.,a spin-glass)of N-10^23 interacting particles may split into an exponential numberΩs-exp(const×N)of ergodic sub-spaces(thermodynamic states).It is usually assumed that the equilibrium collective behavior of such a system is determined by its ground thermodynamic states of the minimal free-energy density,and that the equilibrium free energies follow the distribution of exponentied decay.But actually for some complex systems,the equilibrium free-energy values may follow a Gaussian distribution within an intermediate temperature range,and consequently their equilibrium properties are contributed by excited thermodynamic states.Based on this analysis,the re-weighting parameter y in the cavity approach of spin-glasses is easily understood.Depending on the free-energy distribution,the optimal y can either be equal to or be strictly less than the inverse temperatureβ. 展开更多
关键词 free-energy distribution spin-glass thermodynamic state cavity approach broken ergodicity
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不同冷却方式下锈蚀钢筋混凝土梁火灾后受弯性能试验研究 认领 引用 被引量：2
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作者 刘才玮 杨蒙 +2 位作者 李康 高旭阳 苗吉军 《土木工程学报》 EI CSCD 北大核心 2026年第5期31-43,共13页
为研究锈蚀率、受火时间和冷却方式对钢筋混凝土梁受弯性能的影响,共设计20根混凝土梁进行锈蚀试验、火灾试验以及自然冷却和喷水冷却后的静载试验。采用有限元软件ABAQUS对试件温度场分布和残余抗弯承载力进行模拟分析,并提出锈蚀梁火... 为研究锈蚀率、受火时间和冷却方式对钢筋混凝土梁受弯性能的影响,共设计20根混凝土梁进行锈蚀试验、火灾试验以及自然冷却和喷水冷却后的静载试验。采用有限元软件ABAQUS对试件温度场分布和残余抗弯承载力进行模拟分析,并提出锈蚀梁火灾后受弯承载力计算方法。研究结果表明:随着锈蚀率的增加,受拉钢筋的历经温度提高,试件的残余承载力降低:当受火时间小于60min时,试件承载力约为常温试件的0.81~0.85。受火时间为120min时,受弯承载力发生显著下降,最高可达51.05%:与自然冷却试件相比,喷水冷却试件的承载力下降明显,且可能发生脆性破坏,其延性更差。最后,建议采用修正的中国规范和欧洲规范计算受火时间60min试件的受弯承载力,采用修正的美国规范计算受火时间120min试件的受弯承载力。 展开更多
关键词 锈蚀钢筋混凝土梁 喷水冷却 受弯承载力 数值模拟 承载力计算
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表面织构填充可熔性聚四氟乙烯对WC基涂层摩擦学性能的影响 认领 引用 被引量：1
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作者 何乃如 李康 +3 位作者 范秀娟 李双建 何佳林 杨杰 《中国表面工程》 EI CAS CSCD 北大核心 2026年第2期388-397,共10页
WC系列涂层因其具有高硬度、高耐磨性广泛应用于航空航天、汽车、冶金以及电力等领域。然而,WC系列涂层的摩擦因素较高,易导致配副高磨损。在保证WC基涂层高耐磨性的基础上,为了赋予其自润滑性能,采用真空浸渍方法将具有润滑性能的可熔... WC系列涂层因其具有高硬度、高耐磨性广泛应用于航空航天、汽车、冶金以及电力等领域。然而,WC系列涂层的摩擦因素较高,易导致配副高磨损。在保证WC基涂层高耐磨性的基础上,为了赋予其自润滑性能,采用真空浸渍方法将具有润滑性能的可熔性聚四氟乙烯(PFA)填充到WC-10Co4Cr涂层表面激光织构化沟槽中,系统研究激光织构化及真空浸渍PFA对涂层摩擦学性能的影响。结果表明:WC-10Co4Cr-PFA复合涂层的摩擦因素为0.17,明显优于WC-10Co4Cr涂层(0.36)和表面织构化涂层(0.30),激光织构化和固体润滑剂PFA的协同作用能够赋予涂层优异的自润滑性能。同时,当配副接触表面的PFA润滑膜磨损消耗后,在摩擦热的作用下涂层表面沟槽中PFA黏度降低,并在对偶球的剪切作用下修复磨损表面润滑膜,进而实现涂层润滑相的自补充功能。在100h的摩擦磨损试验中涂层的平均摩擦因数始终保持在0.17左右,具有优异的自润滑寿命。通过织构化浸渍PFA赋予WC-10Co4Cr涂层优异的长寿命自润滑性能,为提升硬质耐磨涂层的润滑性能提供了新思路和方法。 展开更多
关键词 表面织构 真空浸渍 WC-10Co4Cr-PFA复合涂层 自润滑性能 润滑相自补充
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牛顿-拉夫逊优化驱动的自适应密度峰值聚类 认领 引用 被引量：1
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作者 韦修喜 李康 +2 位作者 黄华娟 周永权 庞秋奔 《计算机应用研究》 CSCD 北大核心 2026年第4期1139-1147,共9页
针对密度峰值聚类(DPC)存在的截断距离参数需人工设置、对噪声敏感以及难以适应非均匀数据分布等问题,设计了牛顿-拉夫逊优化驱动的自适应密度峰值聚类方法(NRO-ADPC)。该方法基于牛顿-拉夫逊优化算法建立自适应参数优化机制,通过梯度... 针对密度峰值聚类(DPC)存在的截断距离参数需人工设置、对噪声敏感以及难以适应非均匀数据分布等问题,设计了牛顿-拉夫逊优化驱动的自适应密度峰值聚类方法(NRO-ADPC)。该方法基于牛顿-拉夫逊优化算法建立自适应参数优化机制,通过梯度引导的二阶优化自动确定截断距离,消除人工参数调整依赖;通过构建融合密度连续性、聚类分离度和峰值清晰度的多目标优化函数,结合自适应加权机制增强算法对噪声的鲁棒性;采用结合固定与自适应带宽的混合密度估计策略,在保持全局一致性的同时适应局部分布变化。在5个合成数据集和5个真实数据集上的实验表明,NRO-ADPC在合成数据集上平均准确率超过99%,在真实数据集上相比传统DPC平均提升超过20%。Wilcoxon符号秩检验显示,NRO-ADPC在ACC和NMI指标上相对于MDPC+等对比算法具有统计显著性优势(P<0.05),在处理高噪声、多尺度特征及非均匀分布等复杂数据时表现出色。 展开更多
关键词 密度峰值聚类 牛顿-拉夫逊优化 自适应参数优化 噪声鲁棒性 非均匀分布
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基于分布式时空解耦MPC的无人机集群协同控制 认领 引用
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作者 常绪成 王敬宇 +3 位作者 朱锋 任高峰 李康 刘代军 《控制与决策》 EI CSCD 北大核心 2026年第6期1540-1552,共13页
针对无人机集群协同控制中的高维非凸优化难题,提出一种分布式时空解耦模型预测控制(DSTMPC)框架.首先,将复杂的时空轨迹优化问题解耦为空间几何规划和时间调度两个序贯而协同的子问题:空间层采用基于迭代线性化和自适应信赖域(ILAC)的... 针对无人机集群协同控制中的高维非凸优化难题,提出一种分布式时空解耦模型预测控制(DSTMPC)框架.首先,将复杂的时空轨迹优化问题解耦为空间几何规划和时间调度两个序贯而协同的子问题:空间层采用基于迭代线性化和自适应信赖域(ILAC)的序贯凸化方法处理避障、避碰等非凸约束,并融合控制障碍函数(CBF)确保实时安全;时间层则将轨迹执行转化为高效凸优化问题,通过分布式一致性协议实现集群同步.然后,基于开环解耦系统,设计一种基于冲突状态观测器的时空协同反馈机制,优化时间层至空间层的闭环优化回路.仿真结果表明,所提出框架在不同复杂度场景下均能够实现良好的控制性能:编队误差稳态收敛至0.37 m以内,障碍物最小间距保持在0.2 m以上,验证了所提出方法的有效性和可扩展性,为大规模集群的高效协同控制提供了一种可行方案. 展开更多
关键词 无人机集群 分布式模型预测控制 自适应信赖域 时空解耦 级联稳定性 控制障碍函数
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基于搅拌测黏原理低剪切速率下水煤浆的流变特性 认领 引用
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作者 聂超飞 滕厚兴 +5 位作者 刘罗茜 黄涛 李康 李晓 周芮 刘刚 《中国石油大学学报（自然科学版）》 EI CAS CSCD 北大核心 2026年第2期176-183,共8页
水煤浆是一种非均质的固液悬浮体系,使用同轴圆筒进行流变测试,发现在测试过程中水煤浆发生明显的固相颗粒沉降现象,且在低剪切速率区间内尤为明显;基于“搅拌测黏”原理,使用桨式双弧型测量转子维持固液两相相对均匀的混合状态,对低剪... 水煤浆是一种非均质的固液悬浮体系,使用同轴圆筒进行流变测试,发现在测试过程中水煤浆发生明显的固相颗粒沉降现象,且在低剪切速率区间内尤为明显;基于“搅拌测黏”原理,使用桨式双弧型测量转子维持固液两相相对均匀的混合状态,对低剪切速率下水煤浆的相关流变参数进行测量和表征,研究质量分数、粒径、添加剂等因素对水煤浆黏度的影响效果。结果表明:在低剪切速率区间内,水煤浆颗粒粒径一定,质量分数越大,黏度越大;质量分数一定,颗粒粒径越粗,黏度越大;水煤浆添加分散剂后其黏度明显下降,添加稳定剂后水煤浆黏度明显上升。 展开更多
关键词 水煤浆 低剪切速率 流变特性 搅拌测黏法 流变测试方法
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硫化促进剂太赫兹光谱数据扩充策略与定量检测 认领 引用
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作者 殷贤华 李康 +2 位作者 孙傲 张富强 张活 《光学精密工程》 EI CAS CSCD 北大核心 2026年第8期1219-1231,共13页
为实现橡胶制品中硫化促进剂含量的快速、无损、精准检测,本研究采用太赫兹时域光谱技术,结合数据扩充与化学计量学方法,对多组分橡胶混合物中硫化促进剂进行定量分析。针对橡胶混合物光谱重叠严重、样本量偏小易导致模型过拟合、泛化... 为实现橡胶制品中硫化促进剂含量的快速、无损、精准检测,本研究采用太赫兹时域光谱技术,结合数据扩充与化学计量学方法,对多组分橡胶混合物中硫化促进剂进行定量分析。针对橡胶混合物光谱重叠严重、样本量偏小易导致模型过拟合、泛化能力差等问题,提出基于数据融合与最小二乘高斯拟合法(LSGF)的数据扩充策略,并构建遗传算法优化支持向量回归(GA⁃SVR)定量模型。为降低数据维度、提升建模效率,采用变量空间迭代收缩算法(VISSA)对原始及扩充后光谱进行特征提取。结果表明:数据扩充可显著提升模型预测性能,其中LSGF方法效果最优;经VISSA特征提取后,模型精度进一步提升,LSGF扩充数据在预测集上的相关系数Rp高达0.9826,RMSEP低至0.0023。该方法可为橡胶配方优化与行业绿色可持续发展提供技术参考。 展开更多
关键词 太赫兹光谱 数据扩充 最小二乘高斯拟合 数据融合 定量分析
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通过遗传算法优化和低成本计算机数控制造实现跨频带隐身的全金属超表面 认领 引用
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作者 张明 张娜娇 +4 位作者 李佳磊 李康 Vazgen MELIKYAN 杨琳 侯卫民 《电子与信息学报》 EI CAS CSCD 北大核心 2026年第4期1832-1842,共11页
该文通过单一材料平台集成宽带微波散射(7.4 GHz带宽)与被动红外抑制,为跨波段隐身提供了一种解决方案,克服了传统隐身材料同时兼顾微波吸收与热管理之间的设计挑战。该文提出一种新型全金属随机编码超表面,实现了跨波段隐身功能,兼具... 该文通过单一材料平台集成宽带微波散射(7.4 GHz带宽)与被动红外抑制,为跨波段隐身提供了一种解决方案,克服了传统隐身材料同时兼顾微波吸收与热管理之间的设计挑战。该文提出一种新型全金属随机编码超表面,实现了跨波段隐身功能,兼具微波频段雷达散射截面(RCS)缩减和红外隐身效果。该超表面整体采用铜结构,通过计算机数控(CNC)加工制造,相比传统复合材料设计,消除了界面脱层的风险。同时,其单一材料构造使其能够同时调控微波散射特性和红外辐射特性。该结构通过遗传算法优化相位分布后,在11~18.4 GHz频段(73%带宽)内实现了超过10 dB的RCS缩减,在14.7 GHz频点处的最大抑制效果超过15 dB,相关结果已通过仿真和微波暗室测试验证。该全金属结构在8~14μm红外波段展现出超过99.9%的红外反射率,且通过商业红外成像仪热成像实验证实其被动红外隐身能力,显示出在多光谱隐身应用中的潜力。所制造的原型结构尺寸为150×150 mm2,包含10×10的单元阵列,在最大达60°的线极化斜入射角下仍保持良好的结构稳定性,验证了其在贴合式应用中推广的可行性。 展开更多
关键词 编码超表面 跨波段隐身 逆向设计 低成本制造
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基于语言与非语言刺激的重型创伤性颅脑损伤听觉干预新范式的应用与展望 认领 引用
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作者 李徐龙 袁予哲 +3 位作者 陈鹏 刘志勇 李康 滕海波 《生物医学工程学杂志》 EI CAS 北大核心 2026年第3期625-632,共8页
重型创伤性颅脑损伤患者常伴随深度意识障碍与运动功能受限,导致传统干预手段实施困难。听觉作为重型创伤性颅脑损伤患者保留相对完整的感觉通路之一,在意识障碍评估与意识恢复中的潜力有待深入挖掘。因此,本文系统比较了非语言与语言... 重型创伤性颅脑损伤患者常伴随深度意识障碍与运动功能受限,导致传统干预手段实施困难。听觉作为重型创伤性颅脑损伤患者保留相对完整的感觉通路之一,在意识障碍评估与意识恢复中的潜力有待深入挖掘。因此,本文系统比较了非语言与语言刺激在意识恢复中的作用机制,重点剖析了语言刺激在情绪唤醒与语义整合中的协同作用及其局限性。基于此,利用两者各自优势的互补机制探索了一种新的干预范式,并进一步结合脑机接口技术的发展,提出融合多类型听觉刺激与实时神经反馈的闭环干预思路。该框架强调个体差异与动态调节,为构建精准化、机制导向的重型创伤性颅脑损伤听觉干预范式提供理论依据与发展方向。 展开更多
关键词 创伤性颅脑损伤 听觉干预 语言刺激 意识恢复 闭环脑机接口
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基于RSEI模型的黄河流域生态演变及驱动力 认领 引用
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作者 李晓鹏 李康 +5 位作者 贾富贵 雷双 徐静 李昱鹏 李援农 胡炜童 《水土保持学报》 CAS CSCD 北大核心 2026年第1期451-462,共12页
[目的]为科学评估黄河流域生态环境的动态变化并揭示其驱动机制,旨在系统分析该区域2000—2022年生态环境质量的时空演变特征、预测其未来发展趋势,并探究气温、降水和人类活动对其的影响。[方法]基于遥感生态指数(RSEI)模型,采用Sen趋... [目的]为科学评估黄河流域生态环境的动态变化并揭示其驱动机制,旨在系统分析该区域2000—2022年生态环境质量的时空演变特征、预测其未来发展趋势,并探究气温、降水和人类活动对其的影响。[方法]基于遥感生态指数(RSEI)模型,采用Sen趋势分析、Mann-Kendall(M-K)检验、Hurst指数及其叠加分析方法,对黄河流域2000—2022年生态环境质量变化及其演变趋势进行系统研究,并通过皮尔逊相关性分析探究气温、降水和人类活动强度(HAI)对生态的影响。[结果]1)2000—2022年黄河流域RSEI年平均值为0.473,生态质量整体处于一般水平。2)黄河流域RSEI值呈波动上升趋势,年增长速率为0.0044,表明黄河流域生态质量整体趋于改善。3)未来72.95%的地区RSEI值呈上升趋势,生态环境将得到进一步提升。4)RSEI和HAI的皮尔逊相关系数平均值为-0.159,整体呈负相关。RSEI与气温和降水的皮尔逊相关系数平均值分别为0.081、0.239,整体呈正相关,但空间分异显著。[结论]2000—2022年黄河流域生态环境质量整体处于一般水平但呈波动改善趋势,且未来大部分地区将持续改善。自然因素(气温、降水)和人文因素(人类活动强度)对RSEI均有较为显著的影响。 展开更多
关键词 黄河流域 遥感生态指数 人类活动强度 皮尔逊相关性分析
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大蒜素和番茄红素对湖羊生长性能、血清生化、抗氧化和免疫指标的影响 认领 引用
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作者 智宇 李子南 +9 位作者 李康 田婧 石璐璐 李蕴华 菅瑞珍 师建东 杜红霞 郝宸昉 莎茹拉 郭天龙 《中国畜牧兽医》 CAS CSCD 北大核心 2026年第5期2477-2487,共11页
【目的】探究饲粮中添加大蒜素或番茄红素对湖羊生长性能、血清生化、抗氧化和免疫指标的影响。【方法】选取48只体重相近(24.58±2.16)kg、健康状况良好的3~4月龄湖羊母羊,采用完全随机设计分为3组,每组设4个重复,每个重复4只。对... 【目的】探究饲粮中添加大蒜素或番茄红素对湖羊生长性能、血清生化、抗氧化和免疫指标的影响。【方法】选取48只体重相近(24.58±2.16)kg、健康状况良好的3~4月龄湖羊母羊,采用完全随机设计分为3组,每组设4个重复,每个重复4只。对照组(CON)湖羊饲喂基础饲粮,大蒜素组(GAR)在基础饲粮中添加0.15 g/kg大蒜素,番茄红素组(LYC)在基础饲粮中添加0.20 g/kg番茄红素。预试期15 d,正试期60 d。试验期间记录并计算试验羊的生长性能指标,试验第60天采集试验羊血液,分离血清,测定生化、抗氧化和免疫指标。【结果】与CON组相比,①GAR和LYC组湖羊的初始体重(IBW)、料重比(F/G)均无显著变化(P>0.05),GAR组湖羊的终末体重(FBW)、平均日采食量(ADFI)和平均日增重(ADG)均显著增加(P0.05)。②GAR和LYC组湖羊血清中甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)含量均显著降低(P0.05)。【结论】在本试验条件下,饲粮中添加大蒜素对湖羊的促生长效果更佳,而番茄红素在提高机体总抗氧化能力方面更具优势。2种添加剂均可有效调节湖羊脂代谢、增强免疫功能,在其健康养殖中具有较好的应用潜力。 展开更多
关键词 大蒜素 番茄红素 湖羊 生长性能 抗氧化
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