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Strong Laws of Large Numbers for Sequences of Blockwise m-Dependent and Sub-Orthogonal Random Variables under Sublinear Expectations 被引量:1
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作者 Jialiang FU 《Journal of Mathematical Research with Applications》 2026年第1期103-118,共16页
In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random vari... In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random variables,and another is for sub-orthogonal random variables.Both extend the strong law of large numbers for independent random variables under sublinear expectations to the non-independent case. 展开更多
关键词 sublinear expectations strong law of large numbers blockwise m-dependent suborthogonal random variables
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抑制晶粒噪声的F-number自适应全聚焦优化算法
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作者 张乐 李钦杰 +2 位作者 李一 倪诗杰 肖爱武 《无损检测》 2026年第3期32-37,共6页
奥氏体不锈钢焊缝因晶粒粗大、组织不均匀,在超声检测中会产生严重的结构噪声,导致传统全聚焦方法(TFM)成像的信噪比降低、缺陷轮廓模糊,严重制约了缺陷的检出与定量精度。为此,提出一种基于成像点深度与有效孔径宽度之比的F-number动... 奥氏体不锈钢焊缝因晶粒粗大、组织不均匀,在超声检测中会产生严重的结构噪声,导致传统全聚焦方法(TFM)成像的信噪比降低、缺陷轮廓模糊,严重制约了缺陷的检出与定量精度。为此,提出一种基于成像点深度与有效孔径宽度之比的F-number动态调控自适应全聚焦优化算法。该算法能够动态调控用于合成每个成像点的有效孔径:对于近场或高分辨率需求的浅层区域,自动采用较小的F-number值,汇聚更多阵元信号以获取最优横向分辨率;针对深层成像点或噪声敏感区域,自动增大F-number值,逐步收缩有效合成孔径,主动剔除入射角度过大、易携带强烈晶粒散射噪声的边缘阵元信号,从而显著削弱由晶粒散射引起的非相干噪声。试验结果表明,相较于经典全聚焦算法,所提方法在保持图像高分辨率的同时,图像的性能指标也得到了明显改善,信噪比提高了4%,阵列性能指标降低了8.9%,成像时间减少了36.5%,有效提升了检测的实时性。 展开更多
关键词 奥氏体不锈钢焊缝 超声检测 F-number 自适应全聚焦 晶粒噪声
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Correction models of Reynolds number effects for through-flow method in axial compressors
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作者 Xiaochen WANG Chunwei GU 《Chinese Journal of Aeronautics》 2026年第1期78-94,共17页
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha... Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors. 展开更多
关键词 Axial compressor Reynolds number effects Correction model Through-flow method Aerodynamic performance
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Low-Reynolds-Number Performance of Micro Radial-Flow Turbines at High Altitudes
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作者 Yanzhao Yang Kai Yang +10 位作者 Junwei Zhang Fengsuo Jiang Sheng Xu Lei Chen Jun Bai Luyi Lu Hua Ji Zhihao Jing Senhao Wang Jingjing Zheng Haifeng Zhai 《Fluid Dynamics & Materials Processing》 2026年第1期66-85,共20页
The low-pressure and low-density conditions encountered at high altitudes significantly reduce the operating Reynolds number of micro radial-flow turbines,frequently bringing it below the self-similarity critical thre... The low-pressure and low-density conditions encountered at high altitudes significantly reduce the operating Reynolds number of micro radial-flow turbines,frequently bringing it below the self-similarity critical threshold of 3.5×10^(4).This departure undermines the applicability of conventional similarity-based design approaches.In this study,micro radial-flow turbines with rotor diameters below 50 mm are investigated through a combined approach integrating high-fidelity numerical simulations with experimental validation,aiming to elucidate the mechanisms by which low Reynolds numbers influence aerodynamic and thermodynamic performance.The results demonstrate that decreasing Reynolds number leads to boundary-layer thickening on blade surfaces,enhanced flow separation on the suction side,and increased secondary-flow losses within the blade passages.These effects jointly produce a pronounced and non-linear deterioration of turbine efficiency.Geometric scaling analysis further indicates that efficiency losses intensify with decreasing turbine size,and become particularly severe at low rotational speeds and high expansion ratios.Detailed flow-field analyses reveal a direct link between the degradation of blade loading distribution and the amplification of transverse pressure gradients under low-Reynolds-number conditions,providing physical insight into the observed performance decline. 展开更多
关键词 High altitude low Reynolds number radial-flow turbine aerodynamic performance experimental verification
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Deep learning-based number of sources estimation under colored noise and imperfect array
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作者 Linqiang JIANG Tao TANG +2 位作者 Zhidong WU Ding WANG Paihang ZHAO 《Chinese Journal of Aeronautics》 2026年第2期414-428,共15页
The estimation of the Number of Sources(NoS)is a significant challenge in signal processing,particularly due to the impact of colored noise on the performance of NoS estimation.This paper proposes a Multidimensional F... The estimation of the Number of Sources(NoS)is a significant challenge in signal processing,particularly due to the impact of colored noise on the performance of NoS estimation.This paper proposes a Multidimensional Feature Network(MFNet)which is designed for NoS estimation by extracting features of the sampled received signals and Sampled Covariance Matrix(SCM).The MFNet treats the raw signal and the SCM as two different types of data,and is able to achieve NoS estimation under colored noise and imperfect array.MFNet employs the Gated Recurrent Unit(GRU)to capture sequential information from the original signal data and to construct the Pseudo Covariance Matrix(PCM).Subsequently,various dimensional features,including eigenvalues and the Gerschgorin disk radius,are extracted from both the PCM and SCM,which are then jointly input into the subsequent network.An overall accuracy of 82%can be achieved after network training.The ablation experimental results demonstrate the effectiveness of multiple inputs.And simulation results demonstrate that the proposed MFNet achieves higher estimation accuracy compared to existing algorithms and exhibits greater robustness against colored noise. 展开更多
关键词 number of source estimation Deep learning Colored noise Imperfect array Array signal processing
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Unraveling the missing heritability of amyotrophic lateral sclerosis:Should we focus more on copy number variations?
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作者 Maria Guarnaccia Valentina La Cognata +2 位作者 Giulia Gentile Giovanna Morello Sebastiano Cavallaro 《Neural Regeneration Research》 2026年第5期1997-1998,共2页
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,para... Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016). 展开更多
关键词 degeneration upper lower motor neurons unraveling neurodegenerative disorder missing heritability amyotrophic lateral sclerosis copy number variations
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Suppressors of Cytokinin Receptor Mutant pal1/ohk4 Confer Favorable Alleles of Grain Number 1a(Gn1a)for Improving Grain Yield in japonica Rice
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作者 JIA Huichao CHUN Yan +9 位作者 Ashmit KUMAR MO Tianyu WANG Haifeng GUO Shengyuan FANG Jingjing ZHAO Jinfeng SUN Wei ZHANG Shiyong YUAN Shoujiang LI Xueyong 《Rice science》 2026年第1期81-98,I0068-I0073,共24页
Panicle number per plant,grain number per panicle,and grain weight are three key factors influencing rice grain yield.Gn1a,a major QTL for grain number per panicle,encodes the cytokinin oxidase/dehydrogenase(CKX)OsCKX... Panicle number per plant,grain number per panicle,and grain weight are three key factors influencing rice grain yield.Gn1a,a major QTL for grain number per panicle,encodes the cytokinin oxidase/dehydrogenase(CKX)OsCKX2.While the use of elite Gn1a alleles has been well documented in indica rice cultivars,their potential in japonica rice remains largely unexplored.In this study,we characterized three suppressor mutants of the rice cytokinin receptor mutant pal1/ohk4 and found that all causal genes were novel alleles of Gn1a identified through the MutMap approach.These three suppressor mutants caused single amino acid substitutions in the FAD-binding domain(G556D and G156D)and the cytokinin-binding domain(Y357C),resulting in significantly reduced enzymatic activity of OsCKX2 and elevated cytokinin levels in the panicle.Haplotype analysis of Gn1a using a natural population from the 3K Rice Genomes Project showed that G556D,G156D,and Y357C were novel alleles of Gn1a.G556,G156,and Y357 were highly conserved,whereas four natural variants G54A,A105V,H116R,and N535K identified in different haplotypes of Gn1a showed extremely low conservation.By backcrossing the suppressor mutants with their original wild-type Huaidao 5,an elite japonica rice variety,we developed improved lines carrying only the gn1a mutation.The improved lines showed a significant increase in grain number per panicle,grain weight,panicle number per plant,plant height,and stem thickness,leading to a 25.7%-28.7%increase in grain yield per plot compared with Huaidao 5.This study provides valuable Gn1a alleles for synergistic improvement of the three key yield factors and offers germplasm resources for high-yielding breeding in japonica rice. 展开更多
关键词 grain number panicle size CYTOKININ Gn1a OsCKX2 OHK4/OsHK4 SUPPRESSOR Oryza sativa
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Activity-dependent regulation of cortical cell numbers:Role of neuronal activity in cortical circuit formation
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作者 Fong Kuan Wong 《Neural Regeneration Research》 2026年第8期3521-3522,共2页
The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells... The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells.During development,these cells differ in their origin,birth timing,and developmental trajectories.Nonetheless,they converge during development,forming nascent cortical circuits crucial for organismal behavior.While the relative proportions of cortical cells vary between regions. 展开更多
关键词 neuronal activity mammalian cerebral cortex pyramidal cellsinterneuronsastrocytesmicrogliaoligodendrocytesand cortical cell numbers nascent cortical circuits endothelial cellsduring activity dependent cortical cells
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Determination of the essential number of motoneurons required to produce functionally useful hind limb locomotion
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作者 Zoltán Fekécs Dénes G.Török +4 位作者 Gábor Márton Lászlo Gál Krisztián Pajer Antal Nógrádi Sándor Pintér 《Neural Regeneration Research》 2026年第8期3741-3747,共7页
Avulsion injury of one or more spinal ventral roots induces a critical loss of motoneurons,followed by irreversible locomotor function impairment ranging from inadequate limb movement to complete paralysis of the limb... Avulsion injury of one or more spinal ventral roots induces a critical loss of motoneurons,followed by irreversible locomotor function impairment ranging from inadequate limb movement to complete paralysis of the limb.Recent surgical techniques facilitate improvement of limb function,but it remains to be determined exactly how many motoneurons are needed to survive and grow new axons to achieve sufficient muscle reinnervation.The aim of this study was to determine the minimum motoneuron quantity required to reinnervate the denervated skeletal muscles of the limb and produce a functionally satisfactory locomotor pattern.Since none of the commercially available methods and equipment were able to provide a quantifiable and in-depth analysis of the motor pattern of the entire hind limb,we have developed and applied a sensitive movement recording and analyzing system in order to determine the threshold of satisfactory functional reinnervation;we combined video-based footprint analysis and hind limb motion analysis to achieve a new and reliable assessment.Sprague-Dawley rats underwent a lumbar 4-5 ventral root avulsion,and their L4 ventral roots were subsequently reimplanted.The animals received different doses of riluzole treatment in order to rescue incremental numbers of the damaged motoneuron pool.We were able to assess one rear-view and six lateral parameters of the hind limb movement pattern by measuring specific joint angles,footprint,and gait parameters in single video frames.Four months after the operation,we performed Fast Blue retrograde tracing to label and count the reinnervating motoneurons.We then compared the numbers of reinnervating motoneurons and the functional improvement.Our results confirmed a strong relationship between functional restoration of the original movement pattern and morphological reinnervation;approximately 30%of the original motor pool was able to produce a useful locomotor pattern.We believe that our knowledge of the minimal motoneuron numbers required to reinnervate target muscles may help plan the segmental redistribution of the motoneuron pools for reinnervation surgeries. 展开更多
关键词 AVULSION gait analysis hind limb denervation kinematic analysis minimally required motoneuron number MOTONEURON REINNERVATION retrograde tracing RILUZOLE ventral root reimplantation
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基于Z-numbers-TOPSIS法的老旧小区改造内容优先级决策
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作者 张劲松 汪彬彬 《常州工学院学报》 2026年第1期12-20,共9页
随着城市更新进程加速,老旧小区改造成为关键任务。当前,改造资金主要依赖于财政拨款,鉴于待改造小区数量庞大且改造效果直接影响城市更新质量,因此科学确定改造内容优先级对提升财政资金使用效率至关重要。主要从资金效益、居民需求及... 随着城市更新进程加速,老旧小区改造成为关键任务。当前,改造资金主要依赖于财政拨款,鉴于待改造小区数量庞大且改造效果直接影响城市更新质量,因此科学确定改造内容优先级对提升财政资金使用效率至关重要。主要从资金效益、居民需求及施工难度3个维度出发,构建基于Z-numbers-TOPSIS法的改造内容优先级评价模型,并选取合肥市多个小区进行分析,验证优先级排序的科学性,为政府优化资源配置、制定差异化改造策略提供优化建议。 展开更多
关键词 城市更新 老旧小区改造 TOPSIS Z-numbers 博弈论组合赋权
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The Independence-Separation Problem on the 3-D Rook’s Graph
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作者 Paul A. Burchett 《Open Journal of Discrete Mathematics》 2016年第3期167-173,共7页
Both independence and independence-separation problems on chessboard graphs have been studied in detail, with hundreds of papers in the broader independence category, and several on the independence-separation problem... Both independence and independence-separation problems on chessboard graphs have been studied in detail, with hundreds of papers in the broader independence category, and several on the independence-separation problem variant for chessboard graphs. In this paper, the inde-pendence-separation problem is considered on the d-dimensional rook’s graph. A lower bound of k, for , is found for the independence-separation number on the d-dimensional rook’s graph, denoted by . For the case where , it is found that when n is odd and , . Conjecture and discussion are added. 展开更多
关键词 CHESS independence-separation number Independence number p-Dimensional Grid-Line Graphs p-Dimensional Rook’s Graph
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广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法
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作者 张磊 韩可可 叶鑫 《中国管理科学》 北大核心 2025年第6期160-170,共11页
复杂不确定情景下突发事件应急决策呈现多属性群决策的特征,且在决策信息不确定的情形下,信息的可靠度会影响决策结果。本文提出一种广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法。首先,基于广义Z-numbers对应急决... 复杂不确定情景下突发事件应急决策呈现多属性群决策的特征,且在决策信息不确定的情形下,信息的可靠度会影响决策结果。本文提出一种广义Z-numbers证据下考虑专家影响力和评价值一致性的应急决策方法。首先,基于广义Z-numbers对应急决策问题建模,并构建信任网络分析专家影响力,提出融合专家影响力和评价可靠度的评价值权重分析方法;其次,根据犹豫模糊评价值的交集分析专家的评价值一致性情形,提出不同一致性情形下的证据生成方法,进而利用D-S证据理论融合多证据信息进行备选应对方案的优选决策;最后,以传染性疾病医疗废物处置装置的决策为例,分析验证了所提方法的有效性和决策结果的可信性。 展开更多
关键词 应急决策 广义Z-numbers D-S证据理论 专家影响力 一致性
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Fine-mapping and candidate gene identification for QPtn.sau-4B showing potential in increasing productive tiller number and yield in wheat 被引量:1
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作者 Jiajun Liu Tongzhu Wang +16 位作者 Yuxin Lan Zhiyuan Zhang Jianing You Lei Wu Xinrong Hu Li Yin Yanlin Liu Huaping Tang Qiantao Jiang Qiang Xu Guoyue Chen Pengfei Qi Yunfeng Jiang Yuming Wei Youliang Zheng Chunji Liu Jian Ma 《The Crop Journal》 2025年第2期480-489,共10页
Productive tiller number(PTN)is a pivotal trait that significantly influences wheat grain yield.To date,there have been limited reports on the cloning of genes that regulate PTN in wheat.The quantitative trait locus(Q... Productive tiller number(PTN)is a pivotal trait that significantly influences wheat grain yield.To date,there have been limited reports on the cloning of genes that regulate PTN in wheat.The quantitative trait locus(QTL)QPtn.sau-4B,associated with PTN,was previously mapped between the markers KASP-1 and KASP-3 on the chromosome 4B.Here,utilizing 12 newly developed markers and phenotypic data of PTN from recombinants identified within this interval,QPtn.sau-4B was further fine-mapped to a 2.58 Mb interval on wheat chromosome arm 4BS.Within this interval,we identified 14 genes with high-confidence and 32 genes with low-confidence.A 0.17 Mb deletion fragment contained TraesCS4B03G0092600 and TraesCS4B03G0093100,which were assigned as candidate genes for QPtn.sau-4B.Additionally,QPtn.sau-4B had potential to enhance both PTN and grain yield in wheat.Cloning this locus would support the development of wheat cultivars with increased grain yield. 展开更多
关键词 WHEAT Productive tiller number Grain yield Candidate genes
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Is the relationship between grain number and spike dry weight linear?Insights from larger spikes in wheat 被引量:1
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作者 Román A.Serrago Constanza S.Carrera +1 位作者 Roxana Savin Gustavo A.Slafer 《The Crop Journal》 2025年第2期636-640,共5页
Grain yield variation has been associated to variation in grain number per unit area(GN).It has been shown in the last about 40 years that GN is linearly associated to the spike dry weight(SDW)at anthesis in wheat,fac... Grain yield variation has been associated to variation in grain number per unit area(GN).It has been shown in the last about 40 years that GN is linearly associated to the spike dry weight(SDW)at anthesis in wheat,fact that has been useful to understand mechanistically potential grain yield.Fruiting efficiency(FE,grains per gram of spike dry weight),the slope between GN and SDW relationship,has been proposed as a possible trait to improve wheat yield potential.The linear relationship between GN and SDW implies a constant increase in GN per unit increase in spike growth and,then a constant FE.However,there are empirical and theoretical elements suggesting that this relationship would not be linear.In this study,we hypothesised and showed that the linearity of the relationship between GN and SDW would be non-linear for extreme values of SDW,implying that the FE would be noticeably reduced at these extreme cases of dry matter allocation to the juvenile spikes.These results have implications for both,genetic and management improvements in grain yield. 展开更多
关键词 WHEAT Grain number Spike dry weight Fruiting efficiency
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A low Mach number asymptotic analysis of dissipation-reducing methods for curing shock instability 被引量:1
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作者 Hongping GUO Xun WANG Zhijun SHEN 《Applied Mathematics and Mechanics(English Edition)》 2025年第4期723-744,共22页
We are intrigued by the issues of shock instability,with a particular emphasis on numerical schemes that address the carbuncle phenomenon by reducing dissipation rather than increasing it.For a specific class of plana... We are intrigued by the issues of shock instability,with a particular emphasis on numerical schemes that address the carbuncle phenomenon by reducing dissipation rather than increasing it.For a specific class of planar flow fields where the transverse direction exhibits vanishing but non-zero velocity components,such as a disturbed onedimensional(1D)steady shock wave,we conduct a formal asymptotic analysis for the Euler system and associated numerical methods.This analysis aims to illustrate the discrepancies among various low-dissipative numerical algorithms.Furthermore,a numerical stability analysis of steady shock is undertaken to identify the key factors underlying shock-stable algorithms.To verify the stability mechanism,a consistent,low-dissipation,and shock-stable HLLC-type Riemann solver is presented. 展开更多
关键词 Riemann solver numerical shock instability low Mach number HLLC
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Review on internal flow mechanism and control methods of axial flow compressor at low Reynolds number 被引量:1
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作者 Xuyang REN Xingen LU +6 位作者 Mingyang WANG Ge HAN Chengwu YANG Xu DONG Lipan YAO Yanfeng ZHANG Shengfeng ZHAO 《Chinese Journal of Aeronautics》 2025年第5期7-27,共21页
With the continuous increase of aeroengine flight ceiling(>20 km),the thin atmosphere at high altitudes and the size effect all cause the compressor component inlet Reynolds number to decrease rapidly to a critical... With the continuous increase of aeroengine flight ceiling(>20 km),the thin atmosphere at high altitudes and the size effect all cause the compressor component inlet Reynolds number to decrease rapidly to a critical value(approximately 2.0×10^(5)),and the significant transition process on the blade/endwall surface leads to the sharp degradation of compressor performance,which seriously affects the engine fuel consumption and working stability at high altitudes.In this paper,the research progress on the internal flow mechanism and flow control methods of axial compressors at low Reynolds numbers is reviewed from the aspects of quantification and prediction of performance variation,flow loss mechanism related to separation and transition,efficient transition control and flow field organization.The development trend of the low-Reynolds-number effect of axial flow compressors is noted,and the difficulties and application prospects of aerodynamic design and efficient flow control methods for compressors under low Reynolds numbers at high altitudes are discussed. 展开更多
关键词 LowReynolds number Axial compressor Flow mechanism Flow control methods AEROENGINE
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Health Phys.Abstracts,Volume 128,Number 1
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《辐射防护》 北大核心 2025年第2期191-196,共6页
TENORM Regulation in the United States of America post-West Virginia vs.EPA Spenser Lynn,Charles Wilson,Emily Caffrey1(1.University of Alabama at Birmingham,School of Health Professions,Clinical and Diagnostic Science... TENORM Regulation in the United States of America post-West Virginia vs.EPA Spenser Lynn,Charles Wilson,Emily Caffrey1(1.University of Alabama at Birmingham,School of Health Professions,Clinical and Diagnostic Sciences,Health Physics Program,1720 University Blvd,Birmingham,AL 35294)Abstract:The regulation of technologically enhanced naturally occurring radioactive materials(TENORM)in the United States of America consists of fragmentary rules split between the federal and state governments. 展开更多
关键词 ABSTRACTS number naturally
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The Crossing Number of Two Classes of Join Graphs
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作者 LU Shengxiang WANG Shu WANG Jing 《数学进展》 北大核心 2025年第5期983-991,共9页
Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m... Determining the crossing number of a given graph is NP-complete. The cycle of length m is denoted by Cm = v1v2…vmv1. G^((1))_(m) (m ≥ 5) is the graph obtained from Cm by adding two edges v1v3 and vlvl+2 (3 ≤ l ≤ m−2), G^((2))m (m ≥ 4) is the graph obtained from Cm by adding two edges v1v3 and v2v4. The famous Zarankiewicz’s conjecture on the crossing number of the complete bipartite graph Km,n states that cr(Km,n)=Z(m,n)=[m/2][m-1/2][n/2[n-1/2].Based on Zarankiewicz’s conjecture, a natural problem is to study the change in the crossingnumber of the graphs obtained from the complete bipartite graph by adding certain edge sets.If Zarankiewicz’s conjecture is true, this paper proves that cr(G^((1))_(m)+Kn)=Z(m,n)+2[n/2] and cr(G^((2))_(m)+Kn)=Z(m,n)+n. 展开更多
关键词 crossing number DRAWING join graph
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On the Turán Number of k_(1)P_(ι)∪k_(2)S_(ι-1)
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作者 FANG Tao YUAN Xiying 《数学进展》 北大核心 2025年第4期687-695,共9页
The Turan number of a graph H,denoted by ex(n,H),is the maximum number of edges in any graph on n vertices containing no H as a subgraph.Let P_(ι)denote the path onιvertices,S_(ι-1)denote the star onιvertices and ... The Turan number of a graph H,denoted by ex(n,H),is the maximum number of edges in any graph on n vertices containing no H as a subgraph.Let P_(ι)denote the path onιvertices,S_(ι-1)denote the star onιvertices and k_(1)P_(ι)∪k_(2)S_(ι-1)denote the path-star forest with disjoint union of k_(1)copies of P_(ι)and k_(2)copies of S_(ι-1).In 2022,[Graphs Combin.,2022,38(3):Paper No.84,16 pp.] raised a conjecture about the Turan number of k_(1)P_(2ι)∪k_(2)S_(2ι-1).In this paper,we determine the Turan numbers of P_(ι)∪kS_(ι-1)and k_(1)P_(2ι)∪k_(2)S_(2ι-1)for n appropriately large,which implies the above conjecture.The corresponding extremal graphs are also completely characterized. 展开更多
关键词 Turan number path-star forest extremal graph
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