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Adaptive Meta-Loss Networks:Learning Task-Agnostic Loss Functions via Evolutionary Optimization
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作者 Mirna Yunita Xiabi Liu +1 位作者 Zhaoyang Hai Rachmat Muwardi 《Computers, Materials & Continua》 2026年第5期1931-1949,共19页
Designing appropriate loss functions is critical to the success of supervised learning models.However,most conventional losses are fixed and manually designed,making them suboptimal for diverse and dynamic learning sc... Designing appropriate loss functions is critical to the success of supervised learning models.However,most conventional losses are fixed and manually designed,making them suboptimal for diverse and dynamic learning scenarios.In this work,we propose an Adaptive Meta-Loss Network(Adaptive-MLN)that learns to generate taskagnostic loss functions tailored to evolving classification problems.Unlike traditional methods that rely on static objectives,Adaptive-MLN treats the loss function itself as a trainable component,parameterized by a shallow neural network.To enable flexible,gradient-free optimization,we introduce a hybrid evolutionary approach that combines GeneticAlgorithms(GA)for global exploration and Evolution Strategies(ES)for local refinement.This co-evolutionary process dynamically adjusts the loss landscape,improvingmodel generalization without relying on analytic gradients or handcrafted heuristics.Experimental evaluations on synthetic tasks and the CIFAR-10 andMNIST datasets demonstrate that our approach consistently outperforms standard losses such as Cross-Entropy and Mean Squared Error in terms of accuracy,convergence,and adaptability. 展开更多
关键词 META-LEARNING adaptive loss function task-agnostic optimization evolutionary strategy genetic algorithm CLASSIFICATION
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New Insight to Large Deformation Analysis of Thick-Walled Axisymmetric Functionally Graded Hyperelastic Ellipsoidal Pressure Vessel Structures:A Comparison between FEM and PINNs
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作者 Azhar G.Hamad Nasser Firouzi Yousef S.Al Rjoub 《Computers, Materials & Continua》 2026年第5期403-430,共28页
The accurate mechanical analysis of thick-walled pressure vessel structures composed of advanced materials,such as hyperelastic and functionally graded materials(FGMs),is critical for ensuring their safety and optimiz... The accurate mechanical analysis of thick-walled pressure vessel structures composed of advanced materials,such as hyperelastic and functionally graded materials(FGMs),is critical for ensuring their safety and optimizing their design.However,conventional numerical methods can face challenges with the non-linearities inherent in hyperelasticity and the complex spatial variations in FGMs.This paper presents a novel hybrid numerical approach combining Physics-Informed Neural Networks(PINNs)with Finite Element Method(FEM)derived data for the robust analysis of thick-walled,axisymmetric,heterogeneous,hyperelastic pressure vessels with elliptical geometries.A PINN framework incorporating neo-Hookean constitutive relations is developed in MATLAB.To enhance training efficiency and accuracy,the PINN’s loss function is augmented with displacement data obtained from high-fidelity FEM simulations performed in ANSYS.The methodology is rigorously validated by comparing PINN-predicted displacement and von Mises stress fields against ANSYS benchmarks for various scenarios of FGMconfigurations(with material properties varying according to a power law)subjected to internal and external pressurization.The results demonstrate excellent agreement between the proposed hybrid PINN-FEMapproach and conventional FEMsolutions across all test cases,accurately capturing complex deformation patterns and stress concentrations.This study highlights the potential of data-augmented PINNs as an effective and accurate computational tool for tackling complex solid mechanics problems involving non-linearmaterials and significant heterogeneity,offering a promising avenue for future research in engineering design and analysis. 展开更多
关键词 Finite elementmethod(FEM) physics-informed neural networks(PINNs) HYPERELASTICITY functionally graded materials(FGMs) pressure vessels hybrid numerical methods axisymmetric analysis
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Frobenius函子和k-挠自由模
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作者 常怡 梁力 《东北师大学报(自然科学版)》 北大核心 2026年第1期7-11,共5页
将k-挠自由模的概念从有限生成模推广到无限生成模,采用范畴化的方法证明了Frobenius函子保持并反射无限生成k-挠自由模.
关键词 Frobenius函子 k-挠自由模 无限生成k-挠自由模 有限生成k-挠自由模
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Monel K-500合金真空感应熔炼工艺优化依据及控制
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作者 孙攀贺 李澍 +1 位作者 江河 董建新 《稀有金属材料与工程》 北大核心 2026年第3期756-763,共8页
Monel K-500合金在真空感应熔炼(vacuum induction melting,VIM)浇注过程中铸锭上部易出现大量缩孔缺陷,导致成材率低、质量差。为解决该问题,本研究通过Jmat-Pro热力学计算对Monel K-500合金的热物性能及凝固过程进行了探究。结果表明:... Monel K-500合金在真空感应熔炼(vacuum induction melting,VIM)浇注过程中铸锭上部易出现大量缩孔缺陷,导致成材率低、质量差。为解决该问题,本研究通过Jmat-Pro热力学计算对Monel K-500合金的热物性能及凝固过程进行了探究。结果表明:Monel K-500合金的凝固区间在1250~1350℃;凝固路径为:L→L+γ→L+γ+MC→γ+MC+M_(7)C_(3)→γ'+γ+MC+M_(7)C_(3);凝固过程中随着残余液相质量分数减小,Ni元素发生负偏析,Cu元素发生正偏析。将热力学计算结果结合有限元(FEM)模型,对工业中6 t级Monel K-500合金真空感应熔炼浇注过程进行模拟计算,并将结果和实际真空浇注的感应锭上部缩孔缺陷形状及尺寸进行对比,验证浇注模型的可靠性。此外,本研究依托该模型探究了不同浇注参数对真空感应锭缩孔缺陷的影响,结果表明:添加冒口对真空感应锭中缩孔缺陷的改善最大,随着冒容比增大,真空感应锭中缩孔缺陷体积大幅降低,在冒容比为20%时,真空感应锭中无缩孔缺陷;浇注速度在2.5~17.5 kg/s范围时,随着浇注速度降低,真空感应锭中缩孔体积减小,但小于7.5 kg/s时缩孔缺陷向真空感应锭内部移动。 展开更多
关键词 Monel k-500合金 真空感应熔炼 缩孔缺陷 有限元模型
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Monel K-500合金的热变形行为及物理本构方程
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作者 万亚昌 朱玉亮 +5 位作者 郑文杰 陈明 徐东 奚晓 张开铭 李朝晖 《材料热处理学报》 北大核心 2026年第3期208-216,共9页
在变形温度为900~1100℃及应变速率为0.001~1 s-1的条件下,采用Gleeble-3800型热模拟实验机对Monel K-500合金进行了等温恒应变速率压缩实验。分析了Monel K-500合金的热变形行为,构建了应变补偿型物理本构方程,该方程综合考量了变形温... 在变形温度为900~1100℃及应变速率为0.001~1 s-1的条件下,采用Gleeble-3800型热模拟实验机对Monel K-500合金进行了等温恒应变速率压缩实验。分析了Monel K-500合金的热变形行为,构建了应变补偿型物理本构方程,该方程综合考量了变形温度对合金杨氏模量及自扩散系数的影响。结果表明:随着应变速率的降低和变形温度的升高,Monel K-500合金的流动应力减小;建立的蠕变指数n为5的应变补偿物理本构方程,其相关系数R为0.985,平均相对误差AARE为21.018%;建立的蠕变指数n为变量的应变补偿物理本构方程,其相关系数R为0.995,平均相对误差AARE为5.808%;说明建立的蠕变指数n为变量的应变补偿物理本构方程可较好地表征Monel K-500合金的流动应力行为。 展开更多
关键词 Monel k-500合金 应变补偿物理本构方程 热变形行为 蠕变指数 流动应力
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Some New Subclasses of Meromorphically Multivalent Uniformly Reciprocal Starlike Functions Defined by the Generalized Dziok-Srivastava Operator and Its Integral Operator 被引量:1
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作者 马丽娜 李书海 《Chinese Quarterly Journal of Mathematics》 2015年第4期532-544,共13页
In this paper, we introduce some new subclasses of meromorphically uniformly reciprocal starlike functions associated with the generalized Dziok-Srivastava operator and its corresponding integral operator defined by s... In this paper, we introduce some new subclasses of meromorphically uniformly reciprocal starlike functions associated with the generalized Dziok-Srivastava operator and its corresponding integral operator defined by subordination. We obtain the inclusion relation, sufficient conditions and raajorization property of the class. Moreover, we point out some new and interesting corollaries of our main result. These results generalize some known results. 展开更多
关键词 inclusion relation sufficient condition majorization property the generalized Dziok-srivastava operator integral operator meromorphically multivalent functions reciprocal starlike
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Evaluation of Task-Oriented Training Combined with Lower Limb Rehabilitation Robot on Improvement of Motor Function and Ankle Joint Function in Stroke Patients with Hemiplegia
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作者 Xingjun Shi 《Journal of Clinical and Nursing Research》 2025年第8期332-338,共7页
Objective:To evaluate the effect of task-oriented training combined with a lower limb rehabilitation robot on improving motor function and ankle joint function in stroke patients with hemiplegia.Methods:Sixty-three st... Objective:To evaluate the effect of task-oriented training combined with a lower limb rehabilitation robot on improving motor function and ankle joint function in stroke patients with hemiplegia.Methods:Sixty-three stroke patients with hemiplegia admitted to our hospital from January 2022 to June 2024 were randomly divided into observation group(32 cases)and control group(31 cases)using the envelope method.The control group received task-oriented training,while the observation group received additional lower limb rehabilitation robot training.The motor function(Fugl-Meyer Assessment of Lower Extremity,FMA-LE)and ankle joint function(Active Dorsiflexion Range of Motion,DF AROM)were compared between the two groups.Results:After treatment,the levels of FMA-LE and DF AROM in both groups increased significantly,and the improvement in each index in the observation group was better than that in the control group(P<0.05).Conclusion:The combination of task-oriented training and lower limb rehabilitation robot training can more effectively improve the overall motor function of the lower limbs and the active dorsiflexion ability of the ankle joint in stroke patients with hemiplegia. 展开更多
关键词 STROKE HEMIPLEGIA Task-oriented training Lower limb rehabilitation robot Motor function Ankle joint function
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基于K-S检验的智能电表维修周期评估系统设计
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作者 高洪宇 《家电维修》 2025年第10期15-17,共3页
针对智能电表维修周期预估缺乏科学依据的问题,本文设计了基于K-S检验的维修周期评估系统。通过对电表寿命特性进行统计分析,建立维修周期评估模型,实现维修决策的科学化。系统试运行结果表明,该方法可有效提高维修周期预估准确性。
关键词 k-s检验 智能电表 维修周期 评估系统
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Synthetic metabolic engineering of functional crops:Boosting nutrition and human health 被引量:3
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作者 Nan Chai Jie Xu +12 位作者 Ruixiang Zhang Guangzhou Li Jun Wen Liying Su Yang Xue Tie Li Jialin Liu Dongchang Zeng Jiantao Tan Jiaqi Huang Letian Chen Yao-Guang Liu Qinlong Zhu 《The Crop Journal》 2026年第1期8-21,共14页
A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synth... A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems. 展开更多
关键词 Synthetic biology Synthetic metabolism engineering functional crops Multigene stacking and gene editing Artificial intelligence
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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基于k-中心聚类模型的少数民族音乐文化旅游目的地推荐算法
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作者 周啸 卫叔杨 +2 位作者 潘娟 苏明占 赵太萍 《三门峡职业技术学院学报》 2026年第1期140-148,共9页
少数民族音乐文化旅游开发对于发展民族地区旅游经济具有至关重要的作用。针对少数民族地区音乐文化旅游及文旅融合发展现状和存在问题,笔者构建了基于k-中心聚类模型的少数民族音乐文化旅游目的地推荐算法。实验证明笔者构建的推荐算... 少数民族音乐文化旅游开发对于发展民族地区旅游经济具有至关重要的作用。针对少数民族地区音乐文化旅游及文旅融合发展现状和存在问题,笔者构建了基于k-中心聚类模型的少数民族音乐文化旅游目的地推荐算法。实验证明笔者构建的推荐算法具有可行性和实用性,相比传统推荐算法而言具有更高的准确率和召回率。构建的算法为文旅部门开发旅游推荐系统、旅游信息化服务系统等智慧旅游平台提供了技术参照,为助力少数民族音乐文化旅游建设提供了智力支持。 展开更多
关键词 k-中心聚类 少数民族音乐文化 旅游目的地 推荐算法
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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平行教学实验室:赋能K-12教育的新AI基础设施
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作者 高欣 林飞 +1 位作者 傅君 孙健君 《智能科学与技术学报》 2026年第1期94-104,共11页
为应对中小学(K-12)教学实验室在运行效率、安全保障与智能支持等方面的挑战,引入平行智能,提出了一种以人工系统-计算实验-平行执行(ACP)方法为核心、融合三类人系统的平行教学实验室框架。该框架通过构建人工系统、开展计算实验并实... 为应对中小学(K-12)教学实验室在运行效率、安全保障与智能支持等方面的挑战,引入平行智能,提出了一种以人工系统-计算实验-平行执行(ACP)方法为核心、融合三类人系统的平行教学实验室框架。该框架通过构建人工系统、开展计算实验并实施平行执行,将传统教学实验转化为可计算、可分析、可验证的虚实融合过程。通过系统集成大语言模型、视觉-语言-行动(VLA)等新一代人工智能(AI)技术,支撑实验教学的自主运行与安全可控。围绕平行教学实验室的体系架构、关键技术与运行机制展开分析,并结合天津市第二中学智慧出行AI实验室的建设实践,验证框架在真实教学场景中的可落地性与应用价值。研究表明,平行教学实验室为推动K-12实验教学由静态设施向智能化系统演进提供了一种可行路径。 展开更多
关键词 k-12教育 平行智能 ACP方法 大语言模型 三类人系统 平行教学实验室
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Differing functions of two CYP716 genes for saikosaponin biosynthesis in Bupleurum chinense 被引量:1
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作者 Kaimi Dong Hua Chen +14 位作者 Ma Yu Shiying Wang Xue Yin Chuanxin Mo Meng Zhang Yuchan Li Yong Luo Zeru Yu Zisong Yang Jun Zhao Chao Xin Wenshuai Chen Zhen Ni Zheyong Xue Jianhe Wei 《The Crop Journal》 2026年第1期224-234,共11页
Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the bi... Saikosaponins are the major pharmacologically active components in Bupleurum genus and exhibit significant application potential in multiple fields such as immune regulation and anti-tumor activity.To elucidate the biosynthetic pathway of saikosaponins,we identified two cytochrome P450 monooxygenases,CYP716A41 and CYP716Y4,in Bupleurum chinense.These enzymes catalyze the C-28 oxidation and C-16 hydroxylation of oleanane-type triterpene skeletons,respectively.The catalytic efficiency of CYP716A41 from a southern B.chinense variety was significantly higher than that from a northern variety.Molecular docking and mutagenesis experiments revealed that amino acid residues at sites 9 and 35 may contribute to this difference in catalytic efficiency.Additionally,under cold stress,the expression levels of both CYP450 genes and the saikosaponin contents in the leaves of southern varieties were significantly higher compared to those in northern varieties.The variation in the catalytic efficiency of CYP716A41 and the differential expression of the two CYP450 genes under cold stress during winter are associated with the differences in saikosaponin biosynthesis in the leaves of southern and northern B.chinense varieties.This is consistent with the distinct medicinal usage practices observed between southern and northern China. 展开更多
关键词 Bupleurum chinense Medicinal tissue utilization Saikosaponin biosynthesis pathway CYP716 functional verification
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Certain Subclasses of Analytic Functions Involving the Generalized Dziok-Srivastava Operator
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作者 李书海 汤获 马丽娜 《Chinese Quarterly Journal of Mathematics》 2016年第4期379-389,共11页
The generalized Dziok-Srivastava operator is used here to introduce a class of analytic functions in the open unit disc. We provide convolution properties, some subordination relations and the problem of radius. The r... The generalized Dziok-Srivastava operator is used here to introduce a class of analytic functions in the open unit disc. We provide convolution properties, some subordination relations and the problem of radius. The results presented here extend some of the earlier results. 展开更多
关键词 multivalent functions Dziok-srivastava operator convolution properties subordination relations
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Fekete-Szego Problem for a Subclass of Meromorphic Functions Defined by the Dziok-Srivastava Operator
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作者 Guo Dong Li Zong-tao Xiong Liang-peng 《Communications in Mathematical Research》 CSCD 2018年第2期184-192,共9页
By using the hypergeometric function defined by the Dziok-Srivastava operator, a new subclass of meromorphic function is introdued. We obtain Fekete-Szeg? inequalities for the meromorphic function f(z) for which α-(1... By using the hypergeometric function defined by the Dziok-Srivastava operator, a new subclass of meromorphic function is introdued. We obtain Fekete-Szeg? inequalities for the meromorphic function f(z) for which α-(1 + α{1 +z[_lI_mf(z)]′′/[_lI_mf(z)]′}/z[_lI_mf(z)]′/_lI_mf(z))■φ(z)(α ∈ C-{1/2, 1}). 展开更多
关键词 analytic and meromorphic function starlike and convex function hypergeometric function Fekete-Szeg? problem Dziok-srivastava operator Hadamard product
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k-均值聚类在高维大数据上的高效算法研究进展
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作者 高贵晨 姜少峰 《计算机科学》 北大核心 2026年第4期24-32,共9页
聚类是机器学习中的经典任务,旨在根据相似度度量将数据划分为若干簇。k-均值聚类作为最基本的聚类模型,自提出以来已被深入研究并在众多领域得到广泛应用。聚焦k-均值模型的求解问题,从理论计算机科学的视角出发,介绍k-均值的(接近)线... 聚类是机器学习中的经典任务,旨在根据相似度度量将数据划分为若干簇。k-均值聚类作为最基本的聚类模型,自提出以来已被深入研究并在众多领域得到广泛应用。聚焦k-均值模型的求解问题,从理论计算机科学的视角出发,介绍k-均值的(接近)线性时间的快速近似算法的研究进展。此外,简要讨论其他相关大数据计算模型中的聚类算法的相关进展,包括动态、数据流与并行计算等计算模型。 展开更多
关键词 k-均值 欧氏空间 近线性时间算法 亚线性算法
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基于K-S与S-W双检验法的桩基混凝土耐久性研究
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作者 康峰沂 钱光耀 荣慧 《南通职业大学学报》 2025年第2期99-104,共6页
临海水域氯离子入侵桩基混凝土易引发钢筋锈蚀,导致水下桩基混凝土结构受损,影响使用寿命。针对此,基于20座临海水域桥梁的混凝土桩基耐久性检测数据,采用改进的柯尔莫可洛夫-斯米洛夫(Kolmogorv-Smirnov,K-S)与夏皮罗-威尔克(Shapiro-W... 临海水域氯离子入侵桩基混凝土易引发钢筋锈蚀,导致水下桩基混凝土结构受损,影响使用寿命。针对此,基于20座临海水域桥梁的混凝土桩基耐久性检测数据,采用改进的柯尔莫可洛夫-斯米洛夫(Kolmogorv-Smirnov,K-S)与夏皮罗-威尔克(Shapiro-Wilk,S-W)检验相结合的方法,确定表面氯离子浓度、混凝土保护层厚度、混凝土强度、时间因子及表观氯离子扩散系数的随机分布函数;选取腐蚀起始时间预测模型,建立极限状态方程,并运用蒙特卡罗模拟法,对敏感性区域的水下桩基混凝土的耐久性进行随机模拟预测。结果表明,敏感性区域的水下桩基混凝土预计在64.4~85.1年间出现钢筋锈蚀。 展开更多
关键词 水下桩基混凝土 寿命预测 氯离子侵蚀 k-s检验 S-W检验 蒙特卡罗模拟法
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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Variable reward function-driven strategies for impulsive orbital attack-defense games under multiple constraints and victory conditions
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作者 Liran Zhao Sihan Xu +1 位作者 Qinbo Sun Zhaohui Dang 《Defence Technology(防务技术)》 2025年第9期159-183,共25页
This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breac... This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breach the defender's interception to rendezvous with the target,while the defender seeks to protect the target by blocking or actively pursuing the attacker.Four different maneuvering constraints and five potential game outcomes are incorporated to more accurately model AD game problems and increase complexity,thereby reducing the effectiveness of traditional methods such as differential games and game-tree searches.To address these challenges,this study proposes a multiagent deep reinforcement learning solution with variable reward functions.Two attack strategies,Direct attack(DA)and Bypass attack(BA),are developed for the attacker,each focusing on different mission priorities.Similarly,two defense strategies,Direct interdiction(DI)and Collinear interdiction(CI),are designed for the defender,each optimizing specific defensive actions through tailored reward functions.Each reward function incorporates both process rewards(e.g.,distance and angle)and outcome rewards,derived from physical principles and validated via geometric analysis.Extensive simulations of four strategy confrontations demonstrate average defensive success rates of 75%for DI vs.DA,40%for DI vs.BA,80%for CI vs.DA,and 70%for CI vs.BA.Results indicate that CI outperforms DI for defenders,while BA outperforms DA for attackers.Moreover,defenders achieve their objectives more effectively under identical maneuvering capabilities.Trajectory evolution analyses further illustrate the effectiveness of the proposed variable reward function-driven strategies.These strategies and analyses offer valuable guidance for practical orbital defense scenarios and lay a foundation for future multi-agent game research. 展开更多
关键词 Orbital attack-defense game Impulsive maneuver Multi-agent deep reinforcement learning Reward function design
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