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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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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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Solution set of circumlunar abort trajectory and its direct application to optimization design
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作者 Tianshan DONG Zhen HUANG +2 位作者 Wenyan ZHOU Xiangyu ZHANG Lin LU 《Chinese Journal of Aeronautics》 2026年第1期333-348,共16页
Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar... Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar abort trajectory and leverages its advantageous properties to address the optimization design problem of abort trajectories.Initially,a solution set of all feasible abort trajectories,originating from an abort point on the nominal trajectory and complying with fundamental reentry constraints,is formulated through the introduction of two novel design parameters.Subsequently,the geometric characteristics of the solution set,as well as the distributional properties of key iterative constraint responses,including flight time and velocity increment,are analyzed.Finally,the characteristics exhibited in the solution set are employed to directly identify the design parameters of the abort trajectories with minimum flight time and velocity increment,thereby providing solutions to two distinct types of optimization problems.The simulation results for a variety of nominal trajectories,encompassing the reconstruction and redesign of the Apollo13 abort trajectory,validate the proposed method,demonstrating its ability to directly generate optimal abort trajectories.The method proposed in this paper investigates feasible abort trajectories from a global perspective,providing both a framework and convenience for mission planning and iterative optimization in abort trajectory design. 展开更多
关键词 Circumlunar abort trajectory Design parameters Geometric characteristics Optimization problems Solution set
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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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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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FOXA2 as a SETD1A-Regulated Driver of Tamoxifen Resistance in Breast Cancer
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作者 Myeong Ryeo Kim Jae Rim Lee +1 位作者 Xiaohan Zhang Kwang Won Jeong 《Oncology Research》 2026年第3期539-557,共19页
Objectives:Tamoxifen is a key drug that provides endocrine therapy for estrogen receptor(ER)α-positive breast cancer;however,resistance remains a significant clinical challenge.This study aims to investigate the mole... Objectives:Tamoxifen is a key drug that provides endocrine therapy for estrogen receptor(ER)α-positive breast cancer;however,resistance remains a significant clinical challenge.This study aims to investigate the molecular mechanisms of tamoxifen resistance in ERα-positive breast cancer,with particular focus on the role of SET Domain Containing 1A(SETD1A)-driven forkhead box A2(FOXA2)as a key regulator of this resistance.Methods:FOXA2 expression and its regulation by SETD1A were assessed via(quantitative polymerase chain reaction),western blotting,transcriptome profiling,and chromatin immunoprecipitation analyses.The effects of FOXA2 on cell proliferation,migration,invasion,and cancer stem cell traits were evaluated using small interfering RNA(siRNA)-mediated silencing.Clinical relevance was examined by analyzing patient datasets and tumor tissue microarrays.Results:FOXA2 expression was significantly elevated in tamoxifen-resistant(TamR)and ERα-negative breast cancer cells compared to that in ERα-positive MCF-7 cells,regardless of tamoxifen treatment or ERαdepletion.Transcriptome and chromatin immunoprecipitation analyses revealed that SETD1A,a histone methyltransferase,directly regulated FOXA2 expression.Functionally,FOXA2 knockdown inhibited the proliferation,migration,invasion,and cancer stem cell properties of TamR cells while restoring tamoxifen sensitivity.High FOXA2 expression was correlated with poor survival and reduced responsiveness to tamoxifen in patients with ER-positive breast cancer.Conclusion:Our findings identified FOXA2 as a key mediator of tamoxifen resistance regulated by SETD1A and suggested that targeting the SETD1A-FOXA2 axis may offer a novel strategy for overcoming endocrine resistance in breast cancer. 展开更多
关键词 Tamoxifen resistance forkhead box protein A2 set domain containing 1A breast cancer cancer stem cells
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Cardinal Numbers of Fuzzy Sets 被引量:8
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作者 李洪兴 罗承忠 +1 位作者 汪培庄 袁学海 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期101-107,共7页
Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable ... Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable as we point out in this paper. In the paper, we give a general definition of fuzzy cardinal numbers. Based on this definition, we not only obtain a large part of results with re spect to cardinal numbers, but also give a few of new properties of fuzzy cardinal numbers. 展开更多
关键词 Fuzzy relations Fuzzy mappings the cardinal numbers of fuzzy sets
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SET信号参与的自噬在胃癌进展中的分子机制研究
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作者 张伟 蔡振花 +2 位作者 杨晨 李浩闯 王玉宏 《现代消化及介入诊疗》 2025年第3期305-308,共4页
目的 探究人类SET核原癌基因(SET nuclear proto-oncogene,SET)对胃癌(gastric cancer,GC)细胞自噬途径的作用及机制。方法 通过生物信息学的方法分析SET在GC患者和健康人群中的表达差异。通过慢病毒转染GC细胞系SGC-7901,得到稳定敲低... 目的 探究人类SET核原癌基因(SET nuclear proto-oncogene,SET)对胃癌(gastric cancer,GC)细胞自噬途径的作用及机制。方法 通过生物信息学的方法分析SET在GC患者和健康人群中的表达差异。通过慢病毒转染GC细胞系SGC-7901,得到稳定敲低SET的细胞株。CCK-8法检测细胞增殖活性,划痕实验检测细胞迁移能力,Transwell试验检测细胞侵袭活性。构建裸鼠负瘤模型,3周后取下肿瘤组织。Western blot检测肿瘤组织内自噬相关蛋白sequestosome 1蛋白(sequestosome 1,p62)和自噬相关基因5(autophagy related 5,ATG5)蛋白表达水平。结果 生物信息学分析表明,SET在GC患者中表达水平显著高于健康人群。SET敲低后,SGC7901细胞增殖活性显著降低,迁移和侵袭能力均受到显著抑制。SET敲低抑制了GC肿瘤体内生长。与对照组肿瘤组织相比,SET敲低组肿瘤组织内自噬相关蛋白p62和ATG5表达水平显著升高。结论 SET的表达能够通过抑制细胞自噬途径促进GC进展。 展开更多
关键词 set 自噬 胃癌
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非小细胞肺癌组织中SETDB1、KDM1A、CMTM6表达水平及临床意义
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作者 卢晨 宁光耀 +4 位作者 司盼盼 刘文健 张春盛 张仁泉 赵元 《医学研究与战创伤救治》 北大核心 2025年第9期939-944,共6页
目的探讨非小细胞肺癌(NSCLC)组织中SET结构域分支型组蛋白赖氨酸甲基转移酶1(SETDB1)、赖氨酸特异性组蛋白去甲基化酶1(KDM1A)、趋化因子样因子样MARVEL跨膜结构域含蛋白6(CMTM6)表达与临床病理特征及与预后的关系。方法选择2021年8月... 目的探讨非小细胞肺癌(NSCLC)组织中SET结构域分支型组蛋白赖氨酸甲基转移酶1(SETDB1)、赖氨酸特异性组蛋白去甲基化酶1(KDM1A)、趋化因子样因子样MARVEL跨膜结构域含蛋白6(CMTM6)表达与临床病理特征及与预后的关系。方法选择2021年8月至2022年8月安徽医科大学第一附属医院胸外科收治的102例NSCLC患者。收集癌组织及癌旁组织标本,采用免疫组化法检测癌组织及癌旁组织SETDB1、KDM1A、CMTM6的表达;根据预后情况将患者分为生存组(n=78)和死亡组(n=24),多因素Cox回归分析影响NSCLC患者发生死亡的影响因素,ROC分析SETDB1、KDM1A、CMTM6对NSCLC的诊断价值,Kaplan-Meier法分析SETDB1、KDM1A、CMTM6表达与患者预后的关系。结果NSCLC癌组织SETDB1、KDM1A、CMTM6阳性表达率较癌旁组织均升高(P<0.05);与组织中高分化、TNM分期Ⅰ-Ⅱ期、无淋巴结转移的患者比较,组织低分化、TNM分期Ⅲ-Ⅳ期、有淋巴结转移的患者癌组织中SETDB1、KDM1A、CMTM6阳性表达率均升高(P<0.05);SETDB1、KDM1A、CMTM6三者联合对NSCLC有较高的诊断价值。SETDB1、KDM1A、CMTM6是NSCLC患者发生死亡的危险因素(P<0.05)。SETDB1阳性表达患者生存率低于SETDB1阴性表达患者(P=0.025),KDM1A阳性表达患者生存率低于KDM1A阴性表达患者(P=0.044),CMTM6阳性表达患者生存率低于CMTM6阴性表达患者(P=0.008)。结论NSCLC患者癌组织中SETDB1、KDM1A、CMTM6阳性表达率升高,三者的表达水平与组织分化程度、TNM分期、淋巴结转移以及生存率有关。 展开更多
关键词 非小细胞肺癌 set结构域分支型组蛋白赖氨酸甲基转移酶1 临床病理特征 赖氨酸特异性组蛋白去甲基化酶1 趋化因子样因子样MARVEL跨膜结构域含蛋白6 预后
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A novel similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers with applications to pattern recognition and medical diagnosis 被引量:3
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作者 J Dhivya B Sridevi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第2期229-252,共24页
Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on th... Similarity measure is an essential tool to compare and determine the degree of similarity between intuitionistic fuzzy sets (IFSs). In this paper, a new similarity measure between intuitionistic fuzzy sets based on the mid points of transformed triangular fuzzy numbers is proposed. The proposed similarity measure provides reasonable results not only for the sets available in the literature but also gives very reasonable results, especially for fuzzy sets as well as for most intuitionistic fuzzy sets. To provide supportive evidence, the proposed similarity measure is tested on certain sets available in literature and is also applied to pattern recognition and medical diagnosis problems. It is observed that the proposed similarity measure provides a very intuitive quantification. 展开更多
关键词 FUZZY setS (FSs) Intuitionistic FUZZY setS (IFSs) Most intuitionistic FUZZY setS (MIFSs) Simi- larity measure (SM) Transformed TRIANGULAR FUZZY numberS (TTFNs)
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穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响
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作者 刘小平 陈飞宇 包烨华 《新中医》 2025年第10期87-92,共6页
目的:分析穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响。方法:选取2023年1—12月浙江中医药大学附属杭州市中医院收治的肩袖损伤患者70例,按就诊号的尾数奇偶性随机分为对照组与研究组各35例。对照组采用穴位针刺治... 目的:分析穴位针刺结合SET悬吊技术对肩袖损伤患者术后疼痛、肌肉萎缩的影响。方法:选取2023年1—12月浙江中医药大学附属杭州市中医院收治的肩袖损伤患者70例,按就诊号的尾数奇偶性随机分为对照组与研究组各35例。对照组采用穴位针刺治疗,研究组在对照组的基础上联合SET悬吊技术进行干预。比较2组肩关节功能[加州大学(UCLA)肩关节评分系统评分]、疼痛程度[视觉模拟评分法(VAS)评分]、肩袖肌积分肌电值(iEMG)、肌肉萎缩程度及肩袖肌肉肌腱弹性E值。结果:治疗后,2组UCLA肩关节功能评分均较治疗前升高(P<0.05),且研究组UCLA肩关节功能评分高于对照组(P<0.05)。治疗后,2组肩关节外旋、内旋、内收、外展活动度均较治疗前增大(P<0.05),且研究组肩关节各项活动度均大于对照组(P<0.05)。治疗后,2组疼痛VAS评分均较治疗前降低(P<0.05),且研究组VAS评分低于对照组(P<0.05)。治疗后,2组外展角速度60、120 rad/s时三角肌前束、中束、后束iEMG均较治疗前增大(P<0.05),且研究组上述各项iEMG均大于对照组(P<0.05)。治疗后,研究组肌肉萎缩程度分级改善优于对照组,差异有统计学意义(P<0.05)。治疗后,2组肩袖肌肉肌腱弹性E值均较治疗前降低(P<0.05),且研究组E值低于对照组(P<0.05)。结论:穴位针刺结合SET悬吊技术对肩袖损伤患者术后恢复具有积极影响,可有效减轻术后疼痛,抑制肌肉萎缩,并改善肌肉功能和肌腱弹性。 展开更多
关键词 肩袖损伤 穴位针刺 set悬吊技术 肌肉萎缩 加州大学肩关节评分系统 肩袖肌积分肌电值
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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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A Strong Law of Large Numbers for Set-Valued Random Variables in Gα Space
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作者 Guan Li 《Journal of Applied Mathematics and Physics》 2015年第7期797-801,共5页
In this paper, we shall represent a strong law of large numbers (SLLN) for weighted sums of set- valued random variables in the sense of the Hausdorff metric dH, based on the result of single-valued random variable ob... In this paper, we shall represent a strong law of large numbers (SLLN) for weighted sums of set- valued random variables in the sense of the Hausdorff metric dH, based on the result of single-valued random variable obtained by Taylor [1]. 展开更多
关键词 set-VALUED RANDOM Variable the LAWS of Large numberS HAUSDORFF METRIC
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基于Level Set方法的HG-80钢晶粒长大模型的建模与仿真
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作者 刘铭阳 陈学文 +5 位作者 周正 毛怡然 徐栋栋 李强 易浩 周旭东 《材料热处理学报》 北大核心 2025年第6期162-170,共9页
为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模... 为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模型。通过二次开发将计算所得的Burke-Turnbull模型参数导入DIGIMU■软件中,从晶粒尺寸分布、晶粒生长动力学和晶粒拓扑结构等方面,基于Level Set方法建立了描述HG-80钢的晶粒长大模型并通过DIGIMU■软件进行仿真计算。结果表明:随着保温时间的增加,实验钢的晶粒尺寸明显增大,晶粒生长速率逐渐减小,呈抛物线状增长;为了验证Burke-Turnbull模型的准确性,将平均晶粒尺寸的模型预测值与实验值进行对比,相关系数R为0.991,表明该模型的准确性较高;通过Level Set方法仿真计算得出的晶粒形貌与实验结果吻合良好,证明该模型能有效预测不同热处理条件下HG-80钢的晶粒长大过程。 展开更多
关键词 HG-80钢 Level set方法 晶粒长大 Burke-Turnbull模型
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Numerical Investigation on a Dual-jet Consisting of a Plane Wall Jet and a Parallel Offset Jet at Low-Reynolds Number
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作者 Zhao Liqing Sun Jianhong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第5期778-788,共11页
A dual-jet consisting of a wall jet and an offset jet has been numerically simulated using lattice Boltzmann method to examine the effects of jet spacing between two jet centerlines,defined as s.The Reynolds number ba... A dual-jet consisting of a wall jet and an offset jet has been numerically simulated using lattice Boltzmann method to examine the effects of jet spacing between two jet centerlines,defined as s.The Reynolds number based on jet-exit-width dis set to be Re = 56 and the jet spacing is set to be less than or equal 10 times the jet-exitwidth.Computational results reveal that the flow field displays periodic vortex shedding when the jet spacing is in the range of 9≤s/d ≤ 10,while it remains steady with two counter-rotating vortices in the converging region when s/d ≤ 8.When s/d = 9,the power spectral analyses indicate that the vortex shedding phenomenon has specific frequency.The significant oscillation stresses induced by the periodic components of velocities are found to mainly exist in the inner shear layer regions,implying stronger momentum transfer occuring in these regions. 展开更多
关键词 dual-jet low-Reynolds number lattice BOLTZMANN method vortex SHEDDING
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A Low Mach Number IMEX Flux Splitting for the Level Set Ghost Fluid Method
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作者 Jonas Zeifang Andrea Beck 《Communications on Applied Mathematics and Computation》 2023年第2期722-750,共29页
Considering droplet phenomena at low Mach numbers,large differences in the magnitude of the occurring characteristic waves are presented.As acoustic phenomena often play a minor role in such applications,classical exp... Considering droplet phenomena at low Mach numbers,large differences in the magnitude of the occurring characteristic waves are presented.As acoustic phenomena often play a minor role in such applications,classical explicit schemes which resolve these waves suffer from a very restrictive timestep restriction.In this work,a novel scheme based on a specific level set ghost fluid method and an implicit-explicit(IMEX)flux splitting is proposed to overcome this timestep restriction.A fully implicit narrow band around the sharp phase interface is combined with a splitting of the convective and acoustic phenomena away from the interface.In this part of the domain,the IMEX Runge-Kutta time discretization and the high order discontinuous Galerkin spectral element method are applied to achieve high accuracies in the bulk phases.It is shown that for low Mach numbers a significant gain in computational time can be achieved compared to a fully explicit method.Applica-tions to typical droplet dynamic phenomena validate the proposed method and illustrate its capabilities. 展开更多
关键词 IMEX flux splitting Level set method Ghost fluid method Low Mach number flows
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P-Indeterminate Vector Similarity Measures of Orthopair Neutrosophic Number Sets and Their Decision-MakingMethod with Indeterminate Degrees
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作者 Mailing Zhao Jun Ye 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第9期1219-1230,共12页
In the complexity and indeterminacy of decision making(DM)environments,orthopair neutrosophic number set(ONNS)presented by Ye et al.can be described by the truth and falsity indeterminacy degrees.Then,ONNS demonstrate... In the complexity and indeterminacy of decision making(DM)environments,orthopair neutrosophic number set(ONNS)presented by Ye et al.can be described by the truth and falsity indeterminacy degrees.Then,ONNS demonstrates its advantages in the indeterminate information expression,aggregations,and DM problems with some indeterminate ranges.However,the existing research lacks some similarity measures between ONNSs.They are indispensable mathematical tools and play a crucial role in DM,pattern recognition,and clustering analysis.Thus,it is necessary to propose some similaritymeasures betweenONNSs to supplement the gap.To solve the issue,this study firstly proposes the p-indeterminate cosine measure,p-indeterminate Dice measure,p-indeterminate Jaccard measure of ONNSs(i.e.,the three parameterized indeterminate vector similarity measures of ONNSs)in vector space.Then,a DMmethod based on the parameterized indeterminate vector similarity measures of ONNSs is developed to solve indeterminate multiple attribute DM problems by choosing different indeterminate degrees of the parameter p,such as the small indeterminate degree(p=0)or the moderate indeterminate degree(p=0.5)or the big indeterminate degree(p=1).Lastly,an actual DM example on choosing a suitable logistics supplier is provided to demonstrate the flexibility and practicability of the developed DM approach in indeterminate DM problems.By comparison with existing relative DM methods,the superiority of this study is that the established DMapproach indicates its flexibility and suitability depending on decision makers’indeterminate degrees(decision risks)in ONNS setting. 展开更多
关键词 Orthopair neutrosophic number set p-indeterminate vector similarity measure p-indeterminate cosine measure p-indeterminate Dice measure p-indeterminate Jaccard measure decision making
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OPTIMIZATION OF THE METHOD OF SELECTING THE TOOTH NUMBER SERIES IN A SET OF CHANGE GEARS Part Ⅱ The Rules for Permuting the DBL’s of the First Order and Their Intercalated Sets
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作者 周启澄 《Journal of China Textile University(English Edition)》 EI CAS 1989年第2期76-86,共11页
The problem in practice of determining the proper combination of Z<sub>i</sub> in a set of changegears may be abstracted to the problem of finding the proper combination and permutation ofthe elements a<... The problem in practice of determining the proper combination of Z<sub>i</sub> in a set of changegears may be abstracted to the problem of finding the proper combination and permutation ofthe elements a<sub>i,i+1</sub> of the set A<sub>1</sub> to give maximum M-d. Some results to find optimal combina-tions of the elements of the set A<sub>1</sub> have been reported in part I. In this part, some rules forpermuting these elements are introduced. By means of these rules, three kinds of intercalated setsof A<sub>1</sub> have been found, namely: (1) Sets with an even left wing, (2) Sets with coincidence of bothwings, and (3) Sets with circulated elements. 展开更多
关键词 PERMUTATION CHANGE gear mechanism difference LOGARITHM OPTIMIZATION combination INTERCALATED setS
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Strong Laws of Large Numbers for Fuzzy Set-Valued Random Variables in Gα Space
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作者 Lamei Shen Li Guan 《Advances in Pure Mathematics》 2016年第9期583-592,共10页
In this paper, we shall present the strong laws of large numbers for fuzzy set-valued random variables in the sense of d<sup>&infin;</sup><sub>H</sub> . The results are based on the result ... In this paper, we shall present the strong laws of large numbers for fuzzy set-valued random variables in the sense of d<sup>&infin;</sup><sub>H</sub> . The results are based on the result of single-valued random variables obtained by Taylor [1] and set-valued random variables obtained by Li Guan [2]. 展开更多
关键词 Laws of Large numbers Fuzzy set-Valued Random Variable Hausdorff Metric
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