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一种兼具精度与可解释性的Stacking-SHAP滑坡易发性预测集成方法
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作者 黄鑫 叶健 +3 位作者 刘骋冰 曾秋雨 郭万新 郭志凯 《测绘学报》 北大核心 2025年第10期1826-1840,共15页
滑坡易发性预测及诱因分析对于制定科学有效的滑坡灾害防治策略至关重要。然而,当前仍缺乏能够兼具高预测精度与可解释性的滑坡预测模型。为此,本文提出了一种基于可解释性增强的集成学习方法,构建Stacking-SHAP模型,以提升滑坡易发性... 滑坡易发性预测及诱因分析对于制定科学有效的滑坡灾害防治策略至关重要。然而,当前仍缺乏能够兼具高预测精度与可解释性的滑坡预测模型。为此,本文提出了一种基于可解释性增强的集成学习方法,构建Stacking-SHAP模型,以提升滑坡易发性预测的准确性与诱因分析的可靠性。本文方法采用Stacking集成框架,融合XGBoost、CatBoost、LightGBM、逻辑回归(LR)、随机森林(RF)等多种机器学习分类器,在保证预测精度的基础上,引入SHAP(shapley additive explanations)算法,以增强模型的可解释性。试验结果表明,Stacking-SHAP模型的AUC值达到0.920,显著优于单一分类器模型,如XGBoost(0.893)、CatBoost(0.894)、LightGBM(0.879)、RF(0.859)和LR(0.794)。更重要的是,相较于SHAP集成单一机器学习模型,Stacking-SHAP可解释增强集成模型在滑坡诱因分析方面表现出更优的综合性能,提高了滑坡致灾因素分析的可信度。整体而言,本文方法兼具高精度预测与高可靠性解释,为滑坡易发性预测与诱因分析提供了一种创新性方法,在滑坡防治与减灾领域具有重要的理论与应用价值。 展开更多
关键词 滑坡易发性 地理大数据 Stacking算法 SHAP算法 滑坡诱因分析
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基于MSG-SSD的复合绝缘子憎水性等级智能识别方法
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作者 陈伟华 马士博 +1 位作者 闫孝姮 李健华 《电子测量与仪器学报》 北大核心 2025年第1期234-243,共10页
复合绝缘子憎水性等级的检测是电力系统巡检中的重要环节,针对现有方法存在检测效率低、实时性差及模型结构复杂的问题,提出一种基于MSG-SSD的复合绝缘子憎水性等级智能识别方法。首先,检测模型以SSD算法为基准,采用轻量级MobileNetV2... 复合绝缘子憎水性等级的检测是电力系统巡检中的重要环节,针对现有方法存在检测效率低、实时性差及模型结构复杂的问题,提出一种基于MSG-SSD的复合绝缘子憎水性等级智能识别方法。首先,检测模型以SSD算法为基准,采用轻量级MobileNetV2作为主干网络,在提升模型检测速度的同时实现网络的轻量化;其次,为增强对水迹特征的提取能力,构建高分辨率特征融合模块Sim-HRFPN,在特征融合的同时保留高分辨率的特征,以弥补因轻量化造成的精度损失;最后,为进一步提高模型的计算效率,将GhostConv替换额外预测特征层的传统卷积,在保持模型高性能的同时,减轻了计算负担。实验结果表明,相较于SSD,MSG-SSD的检测速度和检测精度分别提高48.17%和4.89%,计算量和参数量分别减少97.63%和82.99%。由此可知,改进模型不仅能精准识别和快速定位复合绝缘子的憎水性等级,而且满足边缘巡检设备轻量化部署的需求,为电力系统中复合绝缘子运行状态的智能检测提供了一种行之有效的方法。 展开更多
关键词 复合绝缘子 憎水性检测 智能识别 SSD算法 轻量化 特征融合
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基于G-S混合编码的分布式单模光纤测温方法研究
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作者 李昭旭 王宇 +3 位作者 郭欣明 刘昕 白清 靳宝全 《电子测量与仪器学报》 北大核心 2025年第1期244-252,共9页
为了减少分布式单模光纤温度传感系统的测温误差,文中提出了一种基于Golay-Simplex混合编码的单模光纤温度测量方法。首先将4路G码进行S码变换实现了12路G-S混合编码调制,再依次对12路编码输出信号进行S码解码处理与G码解码处理,并采用... 为了减少分布式单模光纤温度传感系统的测温误差,文中提出了一种基于Golay-Simplex混合编码的单模光纤温度测量方法。首先将4路G码进行S码变换实现了12路G-S混合编码调制,再依次对12路编码输出信号进行S码解码处理与G码解码处理,并采用累加平均与小波变换进行了测温曲线降噪,验证了G-S混合编码的编码增益为G码与S码的编码增益乘积。对比实验结果表明,在30 km单模光纤长度、50 ns脉宽与64 bit编码长度的条件下,G-S混合编码测温系统的反斯托克斯信号幅值曲线波动范围较小,且在整个光纤长度内信噪比较大,信噪比高于Golay码编码测温系统和单脉冲测温系统。G-S混合编码的稳态测温误差可从单脉冲系统的±7.3℃优化至±2.5℃,优于Golay编码分布式拉曼光纤测温系统的测温误差±3.9℃。而空间分辨率可保持为5 m,证明了G-S混合编码在长距离单模光纤测温方面的有效性,有望为水利大坝渗漏温变等基础设施状态的融合感知提供有效的技术解决方案。 展开更多
关键词 光纤温度传感 拉曼光时域反射 脉冲编码 g-s混合编码 测温误差
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A Shufled Frog-Leaping Algorithm with Competition for Parallel Batch Processing Machines Scheduling in Fabric Dyeing Process
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作者 Mingbo Li Deming Lei 《Computer Modeling in Engineering & Sciences》 2025年第5期1789-1808,共20页
As a complicated optimization problem,parallel batch processing machines scheduling problem(PBPMSP)exists in many real-life manufacturing industries such as textiles and semiconductors.Machine eligibility means that a... As a complicated optimization problem,parallel batch processing machines scheduling problem(PBPMSP)exists in many real-life manufacturing industries such as textiles and semiconductors.Machine eligibility means that at least one machine is not eligible for at least one job.PBPMSP and scheduling problems with machine eligibility are frequently considered;however,PBPMSP with machine eligibility is seldom explored.This study investigates PBPMSP with machine eligibility in fabric dyeing and presents a novel shuffled frog-leaping algorithm with competition(CSFLA)to minimize makespan.In CSFLA,the initial population is produced in a heuristic and random way,and the competitive search of memeplexes comprises two phases.Competition between any two memeplexes is done in the first phase,then iteration times are adjusted based on competition,and search strategies are adjusted adaptively based on the evolution quality of memeplexes in the second phase.An adaptive population shuffling is given.Computational experiments are conducted on 100 instances.The computational results showed that the new strategies of CSFLA are effective and that CSFLA has promising advantages in solving the considered PBPMSP. 展开更多
关键词 Batch processing machines shuffled frog-leaping algorithm COMPETITION parallel machines scheduling
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Rapid pathologic grading-based diagnosis of esophageal squamous cell carcinoma via Raman spectroscopy and a deep learning algorithm
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作者 Xin-Ying Yu Jian Chen +2 位作者 Lian-Yu Li Feng-En Chen Qiang He 《World Journal of Gastroenterology》 2025年第14期32-46,共15页
BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the e... BACKGROUND Esophageal squamous cell carcinoma is a major histological subtype of esophageal cancer.Many molecular genetic changes are associated with its occurrence.Raman spectroscopy has become a new method for the early diagnosis of tumors because it can reflect the structures of substances and their changes at the molecular level.AIM To detect alterations in Raman spectral information across different stages of esophageal neoplasia.METHODS Different grades of esophageal lesions were collected,and a total of 360 groups of Raman spectrum data were collected.A 1D-transformer network model was proposed to handle the task of classifying the spectral data of esophageal squamous cell carcinoma.In addition,a deep learning model was applied to visualize the Raman spectral data and interpret their molecular characteristics.RESULTS A comparison among Raman spectral data with different pathological grades and a visual analysis revealed that the Raman peaks with significant differences were concentrated mainly at 1095 cm^(-1)(DNA,symmetric PO,and stretching vibration),1132 cm^(-1)(cytochrome c),1171 cm^(-1)(acetoacetate),1216 cm^(-1)(amide III),and 1315 cm^(-1)(glycerol).A comparison among the training results of different models revealed that the 1Dtransformer network performed best.A 93.30%accuracy value,a 96.65%specificity value,a 93.30%sensitivity value,and a 93.17%F1 score were achieved.CONCLUSION Raman spectroscopy revealed significantly different waveforms for the different stages of esophageal neoplasia.The combination of Raman spectroscopy and deep learning methods could significantly improve the accuracy of classification. 展开更多
关键词 Raman spectroscopy Esophageal neoplasia Early diagnosis Deep learning algorithm Rapid pathologic grading
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A Q-Learning-Assisted Co-Evolutionary Algorithm for Distributed Assembly Flexible Job Shop Scheduling Problems
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作者 Song Gao Shixin Liu 《Computers, Materials & Continua》 2025年第6期5623-5641,共19页
With the development of economic globalization,distributedmanufacturing is becomingmore andmore prevalent.Recently,integrated scheduling of distributed production and assembly has captured much concern.This research s... With the development of economic globalization,distributedmanufacturing is becomingmore andmore prevalent.Recently,integrated scheduling of distributed production and assembly has captured much concern.This research studies a distributed flexible job shop scheduling problem with assembly operations.Firstly,a mixed integer programming model is formulated to minimize the maximum completion time.Secondly,a Q-learning-assisted coevolutionary algorithmis presented to solve themodel:(1)Multiple populations are developed to seek required decisions simultaneously;(2)An encoding and decoding method based on problem features is applied to represent individuals;(3)A hybrid approach of heuristic rules and random methods is employed to acquire a high-quality population;(4)Three evolutionary strategies having crossover and mutation methods are adopted to enhance exploration capabilities;(5)Three neighborhood structures based on problem features are constructed,and a Q-learning-based iterative local search method is devised to improve exploitation abilities.The Q-learning approach is applied to intelligently select better neighborhood structures.Finally,a group of instances is constructed to perform comparison experiments.The effectiveness of the Q-learning approach is verified by comparing the developed algorithm with its variant without the Q-learning method.Three renowned meta-heuristic algorithms are used in comparison with the developed algorithm.The comparison results demonstrate that the designed method exhibits better performance in coping with the formulated problem. 展开更多
关键词 Distributed manufacturing flexible job shop scheduling problem assembly operation co-evolutionary algorithm Q-learning method
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An Adaptive Cooperated Shuffled Frog-Leaping Algorithm for Parallel Batch Processing Machines Scheduling in Fabric Dyeing Processes
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作者 Lianqiang Wu Deming Lei Yutong Cai 《Computers, Materials & Continua》 2025年第5期1771-1789,共19页
Fabric dyeing is a critical production process in the clothing industry and heavily relies on batch processing machines(BPM).In this study,the parallel BPM scheduling problem with machine eligibility in fabric dyeing ... Fabric dyeing is a critical production process in the clothing industry and heavily relies on batch processing machines(BPM).In this study,the parallel BPM scheduling problem with machine eligibility in fabric dyeing is considered,and an adaptive cooperated shuffled frog-leaping algorithm(ACSFLA)is proposed to minimize makespan and total tardiness simultaneously.ACSFLA determines the search times for each memeplex based on its quality,with more searches in high-quality memeplexes.An adaptive cooperated and diversified search mechanism is applied,dynamically adjusting search strategies for each memeplex based on their dominance relationships and quality.During the cooperated search,ACSFLA uses a segmented and dynamic targeted search approach,while in non-cooperated scenarios,the search focuses on local search around superior solutions to improve efficiency.Furthermore,ACSFLA employs adaptive population division and partial population shuffling strategies.Through these strategies,memeplexes with low evolutionary potential are selected for reconstruction in the next generation,while thosewithhighevolutionarypotential are retained to continue their evolution.Toevaluate the performance of ACSFLA,comparative experiments were conducted using ACSFLA,SFLA,ASFLA,MOABC,and NSGA-CC in 90 instances.The computational results reveal that ACSFLA outperforms the other algorithms in 78 of the 90 test cases,highlighting its advantages in solving the parallel BPM scheduling problem with machine eligibility. 展开更多
关键词 Batch processing machine parallel machine scheduling shuffled frog-leaping algorithm fabric dyeing process machine eligibility
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Hop-to-Hug algorithm:Novel strategy to stable cutting-plane algorithm based on convexification of yield functions
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作者 Yanbin Chen Yuanming Lai Enlong Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2041-2058,共18页
Numerical challenges,incorporating non-uniqueness,non-convexity,undefined gradients,and high curvature,of the positive level sets of yield function are encountered in stress integration when utilizing the return-mappi... Numerical challenges,incorporating non-uniqueness,non-convexity,undefined gradients,and high curvature,of the positive level sets of yield function are encountered in stress integration when utilizing the return-mapping algorithm family.These phenomena are illustrated by an assessment of four typical yield functions:modified spatially mobilized plane criterion,Lade criterion,Bigoni-Piccolroaz criterion,and micromechanics-based upscaled Drucker-Prager criterion.One remedy to these issues,named the"Hop-to-Hug"(H2H)algorithm,is proposed via a convexification enhancement upon the classical cutting-plane algorithm(CPA).The improved robustness of the H2H algorithm is demonstrated through a series of integration tests in one single material point.Furthermore,a constitutive model is implemented with the H2H algorithm into the Abaqus/Standard finite-element platform.Element-level and structure-level analyses are carried out to validate the effectiveness of the H2H algorithm in convergence.All validation analyses manifest that the proposed H2H algorithm can offer enhanced stability over the classical CPA method while maintaining the ease of implementation,in which evaluations of the second-order derivatives of yield function and plastic potential function are circumvented. 展开更多
关键词 Elastoplastic model Constitutive model integration Cutting-plane algorithm Geotechnical analysis Finite element method(FEM)
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Convergence of 6G-Empowered Edge Intelligence and Generative AI:Theories,Algorithms,and Applications
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作者 Wu Yuan Dusit Niyato +5 位作者 Cui Shuguang Zhao Lian Tony Q.S.Quek Zhang Yan Qian Liping Li Rongpeng 《China Communications》 2025年第7期I0002-I0005,共4页
The rapid advancement of 6G communication technologies and generative artificial intelligence(AI)is catalyzing a new wave of innovation at the intersection of networking and intelligent computing.On the one hand,6G en... The rapid advancement of 6G communication technologies and generative artificial intelligence(AI)is catalyzing a new wave of innovation at the intersection of networking and intelligent computing.On the one hand,6G envisions a hyper-connected environment that supports ubiquitous intelligence through ultra-low latency,high throughput,massive device connectivity,and integrated sensing and communication.On the other hand,generative AI,powered by large foundation models,has emerged as a powerful paradigm capable of creating. 展开更多
关键词 G ubiquitous intelligence edge intelligence algorithmS generative artificial intelligence ai theories large foundation modelshas intelligent computingon
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Clustering-based recommendation method with enhanced grasshopper optimisation algorithm
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作者 Zihao Zhao Yingchun Xia +7 位作者 Wenjun Xu Hui Yu Shuai Yang Cheng Chen Xiaohui Yuan Xiaobo Zhou Qingyong Wang Lichuan Gu 《CAAI Transactions on Intelligence Technology》 2025年第2期494-509,共16页
In the era of big data,personalised recommendation systems are essential for enhancing user engagement and driving business growth.However,traditional recommendation algorithms,such as collaborative filtering,face sig... In the era of big data,personalised recommendation systems are essential for enhancing user engagement and driving business growth.However,traditional recommendation algorithms,such as collaborative filtering,face significant challenges due to data sparsity,algorithm scalability,and the difficulty of adapting to dynamic user preferences.These limitations hinder the ability of systems to provide highly accurate and personalised recommendations.To address these challenges,this paper proposes a clustering-based recommendation method that integrates an enhanced Grasshopper Optimisation Algorithm(GOA),termed LCGOA,to improve the accuracy and efficiency of recommendation systems by optimising cluster centroids in a dynamic environment.By combining the K-means algorithm with the enhanced GOA,which incorporates a Lévy flight mechanism and multi-strategy co-evolution,our method overcomes the centroid sensitivity issue,a key limitation in traditional clustering techniques.Experimental results across multiple datasets show that the proposed LCGOA-based method significantly outperforms conventional recommendation algorithms in terms of recommendation accuracy,offering more relevant content to users and driving greater customer satisfaction and business growth. 展开更多
关键词 collaborative recommendation Grasshopper Optimization algorithm(GOA) K‐means clustering Lévy flight
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Identification of key brain networks and functional connectivities of successful aging:A surface-based resting-state functional magnetic resonance study
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作者 Jiao-Jiao Sun Li Zhang +3 位作者 Ru-Hong Sun Xue-Zheng Gao Chun-Xia Fang Zhen-He Zhou 《World Journal of Psychiatry》 2025年第3期216-226,共11页
BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explo... BACKGROUND Successful aging(SA)refers to the ability to maintain high levels of physical,cognitive,psychological,and social engagement in old age,with high cognitive function being the key to achieving SA.AIM To explore the potential characteristics of the brain network and functional connectivity(FC)of SA.METHODS Twenty-six SA individuals and 47 usual aging individuals were recruited from community-dwelling elderly,which were taken the magnetic resonance imaging scan and the global cognitive function assessment by Mini Mental State Examination(MMSE).The resting state-functional magnetic resonance imaging data were preprocessed by DPABISurf,and the brain functional network was conducted by DPABINet.The support vector machine model was constructed with altered functional connectivities to evaluate the identification value of SA.RESULTS The results found that the 6 inter-network FCs of 5 brain networks were significantly altered and related to MMSE performance.The FC of the right orbital part of the middle frontal gyrus and right angular gyrus was mostly increased and positively related to MMSE score,and the FC of the right supramarginal gyrus and right temporal pole:Middle temporal gyrus was the only one decreased and negatively related to MMSE score.All 17 significantly altered FCs of SA were taken into the support vector machine model,and the area under the curve was 0.895.CONCLUSION The identification of key brain networks and FC of SA could help us better understand the brain mechanism and further explore neuroimaging biomarkers of SA. 展开更多
关键词 Successful aging Resting-state functional magnetic resonance imaging Surface-based brain network analysis Functional connectivity Support vector machine algorithm
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Dimensional synchronous modeling-based enhanced Kriging algorithm and adaptive Copula method for multi-objective synthetical reliability analyses
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作者 Cheng LU Yunwen FENG +1 位作者 Chengwei FEI Da TENG 《Chinese Journal of Aeronautics》 2025年第9期144-165,共22页
To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise mode... To accomplish the reliability analyses of the correlation of multi-analytical objectives,an innovative framework of Dimensional Synchronous Modeling(DSM)and correlation analysis is developed based on the stepwise modeling strategy,cell array operation principle,and Copula theory.Under this framework,we propose a DSM-based Enhanced Kriging(DSMEK)algorithm to synchronously derive the modeling of multi-objective,and explore an adaptive Copula function approach to analyze the correlation among multiple objectives and to assess the synthetical reliability level.In the proposed DSMEK and adaptive Copula methods,the Kriging model is treated as the basis function of DSMEK model,the Multi-Objective Snake Optimizer(MOSO)algorithm is used to search the optimal values of hyperparameters of basis functions,the cell array operation principle is adopted to establish a whole model of multiple objectives,the goodness of fit is utilized to determine the forms of Copula functions,and the determined Copula functions are employed to perform the reliability analyses of the correlation of multi-analytical objectives.Furthermore,three examples,including multi-objective complex function approximation,aeroengine turbine bladeddisc multi-failure mode reliability analyses and aircraft landing gear system brake temperature reliability analyses,are performed to verify the effectiveness of the proposed methods,from the viewpoints of mathematics and engineering.The results show that the DSMEK and adaptive Copula approaches hold obvious advantages in terms of modeling features and simulation performance.The efforts of this work provide a useful way for the modeling of multi-analytical objectives and synthetical reliability analyses of complex structure/system with multi-output responses. 展开更多
关键词 Adaptive Copula method Aeroengine turbine bladeddisc Aircraft landing gear system Correlation of multianalytical objectives Dimensional synchronous modeling-based enhanced Kriging algorithm Reliability analyses
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基于Log-sum正则化的稀疏神经网络
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作者 谢文杰 刘玉兰 《广东工业大学学报》 2025年第6期78-85,共8页
为了训练出一个稀疏的神经网络,本文选用Log-sum函数作为正则项,交叉熵函数作为损失项建立模型,随后用邻近梯度法对它进行求解,其学习率用Meta-LR-Schedule-Net网络训练得到。在MNIST、Fashion-MNIST、CIFAR-10和CIFAR-100四个数据集上... 为了训练出一个稀疏的神经网络,本文选用Log-sum函数作为正则项,交叉熵函数作为损失项建立模型,随后用邻近梯度法对它进行求解,其学习率用Meta-LR-Schedule-Net网络训练得到。在MNIST、Fashion-MNIST、CIFAR-10和CIFAR-100四个数据集上的数值实验结果表明:在同样的学习率规则下,用Log-sum函数作为正则项比用其他能诱导稀疏的函数,如向量1范数、截尾向量1范数或向量1/2范数等作为正则项建立的模型能把网络训练得更稀疏;在稀疏度近似的情况下,用Meta-LR-Schedule-Net训练得到的学习率,比使用固定规则训练得到的网络有更高的正确率。 展开更多
关键词 稀疏神经网络 Log-sum函数 邻近梯度法
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次线性g-期望的稳健表示及其应用研究
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作者 李敏 纪荣林 +1 位作者 钟文倩 周津名 《哈尔滨商业大学学报(自然科学版)》 2025年第4期474-479,共6页
在关于g-期望定义的基本假设条件下,基于倒向随机微分方程理论,深入探讨了生成元函数在刻画次线性g-期望的稳健表示中的核心作用.通过分析生成元函数的性质,在L^(p)(1<p≤∞)空间中建立了次线性g-期望的稳健表示定理.研究结果表明,... 在关于g-期望定义的基本假设条件下,基于倒向随机微分方程理论,深入探讨了生成元函数在刻画次线性g-期望的稳健表示中的核心作用.通过分析生成元函数的性质,在L^(p)(1<p≤∞)空间中建立了次线性g-期望的稳健表示定理.研究结果表明,在适当的可积性条件下,次线性g-期望可以表示为一类概率测度族上的上确界期望,这一发现本质性地拓展了非线性期望的表示框架.进一步地,获得了g-期望诱导的一致性风险度量的稳健表示模型.该模型满足单调性、平移不变性、次可加性和正齐次性等一致性公理,从而在金融风险管理中具有重要应用. 展开更多
关键词 倒向随机微分方程 g-期望 生成元 次线性g-期望 稳健表示 一致性风险度量
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G-度量空间上积分型压缩映射对的公共不动点定理
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作者 关洪岩 李超 《沈阳师范大学学报(自然科学版)》 2025年第1期70-74,共5页
在非线性分析中,Banach引入的Banach压缩映射原理是一个解决度量空间中的不动点的存在性和唯一性问题的经典而有力的工具,在基础数学和计算数学中有着广泛的应用,近年来在多个角度得到了推广。在G-度量空间的背景下,研究满足CLR性质的... 在非线性分析中,Banach引入的Banach压缩映射原理是一个解决度量空间中的不动点的存在性和唯一性问题的经典而有力的工具,在基础数学和计算数学中有着广泛的应用,近年来在多个角度得到了推广。在G-度量空间的背景下,研究满足CLR性质的积分型压缩映射对具有公共不动点的条件。首先,在G-度量空间中引入可变距离函数Φ;其次,根据2个映射的包含关系构造一个序列,并通过Φ的性质、压缩条件等证明该序列是柯西列;再次,结合空间的完备性和压缩条件,得出这2个映射具有重合值,根据弱相容映射的性质,证明该映射对公共不动点的存在性,进而证明公共不动点的唯一性;最后,给出一个例子说明该定理的有效性。 展开更多
关键词 不动点 Φ函数 g-度量空间 CLR性质
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G-菌血流感染患者循环sCD14-ST、G6PD、乳酸与PCT、CRP、内毒素的相关性及对脓毒症的预测价值
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作者 李攀 段红茹 +2 位作者 陈芳 姚伟莉 王威 《检验医学与临床》 2025年第10期1410-1415,共6页
目的探讨G-菌血流感染患者循环可溶性白细胞分化抗原14亚型(sCD14-ST)、葡萄糖-6-磷酸脱氢酶(G6PD)、乳酸与降钙素原(PCT)、C反应蛋白(CRP)、内毒素的相关性及对脓毒症的预测价值。方法选取2022年1月至2024年3月河北省保定市第一中心医... 目的探讨G-菌血流感染患者循环可溶性白细胞分化抗原14亚型(sCD14-ST)、葡萄糖-6-磷酸脱氢酶(G6PD)、乳酸与降钙素原(PCT)、C反应蛋白(CRP)、内毒素的相关性及对脓毒症的预测价值。方法选取2022年1月至2024年3月河北省保定市第一中心医院ICU收治的115例G-菌血流感染患者作为研究对象,根据是否发生脓毒症分为脓毒症组、非脓毒症组。比较2组治疗前循环sCD14-ST、G6PD、乳酸水平与血清PCT、CRP、内毒素水平,采用Pearson相关分析G-菌血流感染脓毒症患者血清循环sCD14-ST、G6PD、乳酸、PCT、CRP、内毒素水平相关性,绘制受试者工作特征(ROC)曲线分析循环sCD14-ST、G6PD、乳酸、PCT、CRP、内毒素、sCD14-ST+G6PD+乳酸、PCT+CRP+内毒素预测脓毒症的价值。结果脓毒症组纳入52例,非脓毒症组纳入63例。脓毒症组循环sCD14-ST、乳酸、PCT、CRP、内毒素水平均高于非脓毒症组,G6PD水平低于非脓毒症组,差异均有统计学意义(P<0.05)。Pearson相关分析结果显示,G-菌血流感染脓毒症患者血清循环sCD14-ST水平与PCT、CRP、内毒素水平均呈正相关(r=0.780、0.721、0.737,P<0.001),乳酸水平与PCT、CRP、内毒素水平均呈正相关(r=0.790、0.811、0.818,P<0.001),循环G6PD水平与PCT、CRP、内毒素水平呈负相关(r=-0.789、-0.831、-0.778,P<0.001)。ROC曲线分析结果显示,循环sCD14-ST、G6PD、乳酸与PCT、CRP、内毒素单独预测脓毒症曲线下面积(AUC)均>0.7,有一定的预测价值,其中sCD14-ST的AUC最大,G6PD、乳酸的AUC与传统指标PCT、CRP、内毒素的AUC相近。sCD14-ST+G6PD+乳酸联合预测脓毒症的AUC为0.950;PCT+CRP+内毒素联合预测脓毒症的AUC为0.874。sCD14-ST+G6PD+乳酸联合预测脓毒症的AUC高于sCD14-ST、G6PD、乳酸单独预测的AUC(Z=2.305、3.264、3.264,P=0.035、0.018、0.018);PCT+CRP+内毒素联合预测脓毒症的AUC大于PCT、CRP、内毒素单独预测的AUC(Z=1.975、2.005、2.004,P=0.046、0.038、0.039);sCD14-ST+G6PD+乳酸联合预测脓毒症的AUC大于PCT+CRP+内毒素联合预测的AUC(Z=1.966,P=0.049)。结论循环sCD14-ST、G6PD、乳酸与G-菌血流感染患者PCT、CRP、内毒素相关,sCD14-ST+G6PD+乳酸对并发脓毒症的预警能力高于传统指标联合,在缺乏有效的预测手段时,有望为早期预测脓毒症的高风险人群提供重要的参考信息。 展开更多
关键词 溶性白细胞分化抗原14亚型 葡萄糖-6-磷酸脱氢酶 乳酸 g-菌血流感染 降钙素原 C反应蛋白 内毒素 相关性 脓毒症
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G-α-E-半预不变凸规划的Wolfe型对偶
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作者 李钰 魏佳 《贵州大学学报(自然科学版)》 2025年第3期26-34,共9页
介绍了一类新的广义不变凸函数,其称为G-α-E-半预不变凸函数;探讨了与此类函数相关的多目标规划问题,并给出这类问题的最优性充分条件;最后,建立了相对应的Wolfe型对偶模型,并讨论该模型与原问题之间的可行解和有效解之间的关系,获得... 介绍了一类新的广义不变凸函数,其称为G-α-E-半预不变凸函数;探讨了与此类函数相关的多目标规划问题,并给出这类问题的最优性充分条件;最后,建立了相对应的Wolfe型对偶模型,并讨论该模型与原问题之间的可行解和有效解之间的关系,获得了弱对偶、强对偶、逆对偶定理。研究丰富了已有文献中与广义凸规划有关的Wolfe型对偶理论。 展开更多
关键词 g-α-E-半预不变凸函数 多目标规划 最优性条件 WOLFE型对偶
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改进5G-R自适应高速铁路越区切换算法 被引量:2
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作者 陈永 康婕 陶瑄 《北京航空航天大学学报》 北大核心 2025年第3期724-731,共8页
在高速行车条件下,越区切换作为未来高速铁路5G-R通信的关键技术,对于保障行车安全至关重要。下一代高速铁路5G-R无线通信系统越区切换算法采用固定切换参数,但当列车高速运行时,极易受到多普勒效应影响,导致切换成功率低,基于此,提出... 在高速行车条件下,越区切换作为未来高速铁路5G-R通信的关键技术,对于保障行车安全至关重要。下一代高速铁路5G-R无线通信系统越区切换算法采用固定切换参数,但当列车高速运行时,极易受到多普勒效应影响,导致切换成功率低,基于此,提出了一种考虑多普勒频移影响的改进5G-R自适应高速铁路越区切换算法。分析多普勒频移对切换成功率的影响,得到多普勒频移与切换成功率的关系函数;提出考虑多普勒频移影响的越区切换动态函数,设计余弦、余切、余割3种函数对切换迟滞门限及触发时延自适应调整;在不同多普勒频移及不同高铁场景下进行切换成功率的量化比较分析。研究结果表明:所提算法可有效调高切换成功率,在高架桥和山区场景下,余弦、余切、余割3种函数的切换成功率均优于对比算法,且满足中国无线通信系统切换成功率服务质量(QoS)大于99.5%的要求。研究结果为下一代高速铁路5G-R无线通信系统演进提供了理论参考依据。 展开更多
关键词 越区切换算法 5g-R 多普勒频移 动态函数 自适应切换
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基于MIC-NNG-LSTM的有机废液焚烧SCR入口NO_(x)浓度动态预测
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作者 李艳 史艳华 +2 位作者 戴庆瑜 刘嫣 马晓燕 《工程科学与技术》 北大核心 2025年第3期21-30,共10页
针对高盐有机废液焚烧及烟气处理过程中普遍存在的延迟、非线性和动态特性,提出一种基于自适应变量选择与长短期记忆神经网络(MIC-NNG-LSTM)的动态预测方法,对选择性催化还原法(SCR)脱硝塔入口NO_(x)浓度进行预测,解决当工况发生变化时... 针对高盐有机废液焚烧及烟气处理过程中普遍存在的延迟、非线性和动态特性,提出一种基于自适应变量选择与长短期记忆神经网络(MIC-NNG-LSTM)的动态预测方法,对选择性催化还原法(SCR)脱硝塔入口NO_(x)浓度进行预测,解决当工况发生变化时,脱硝系统不能及时调整喷氨量的问题。该预测方法在传统长短期记忆神经网络(LSTM)的基础上,利用最大互信息系数(MIC)法确定相关辅助变量的延迟时间,以全面捕捉变量之间的动态关系。其次,利用MIC可以反映各输入变量相对于目标变量的重要程度,结合能够收缩变量系数的非负绞杀(NNG)算法,设计MIC-NNG算法来压缩LSTM网络的输入节点数,剔除冗余变量,实现辅助变量的自适应选择。最后,将包含延迟时间的辅助变量集作为LSTM网络的输入变量集,从而建立SCR入口NO_(x)浓度动态预测模型。并与LSTM、MICLSTM、NNG-LSTM 3种预测SCR入口NO_(x)浓度的方法进行实验对比,浓度预测精度可达到93%,均方根误差减小为约1.5 mg/Nm^(3)。结果表明:通过引入输入变量的延迟时间特性,能够更好地体现各变量之间的动态关系;MIC-NNG算法相对于NNG算法能更准确地选择输入变量以缩短模型预测时间,提高预测精度和泛化能力。基于MIC-NNG算法和LSTM网络的动态预测模型综合考虑了有机废液焚烧过程中变量的延迟特性和各参数之间的动态时序关系,可以为降低NO_(x)排放量提供新思路。 展开更多
关键词 有机废液 动态预测 变量选择 长短期记忆神经网络 MIC-NNG算法
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Ordering of high-density markers by the k-Optimal algorithm for the traveling-salesman problem 被引量:6
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作者 Luyan Zhang Huihui Li +1 位作者 Lei Meng Jiankang Wang 《The Crop Journal》 SCIE CAS CSCD 2020年第5期701-712,共12页
Construction of accurate and high-density linkage maps is a key research area of genetics.We investigated the efficiency of genetic map construction(MAP)using modifications of the k-Optimal(k-Opt)algorithm for solving... Construction of accurate and high-density linkage maps is a key research area of genetics.We investigated the efficiency of genetic map construction(MAP)using modifications of the k-Optimal(k-Opt)algorithm for solving the traveling-salesman problem(TSP).For TSP,different initial routes resulted in different optimal solutions.The most optimal solution could be found only by use of as many initial routes as possible.But for MAP,a large number of initial routes resulted in one optimal order.k-Opt using open route length gave a slightly higher proportion of correct orders than the method of adding one virtual marker and using closed route length.Recombination frequency(REC)and logarithm of odds(LOD)score gave similar proportions of correct order,higher than that given by genetic distance.Both missing markers and genotyping error reduced ordering accuracy,but the best order was still achieved with high probability by comparison of the optimal orders from multiple initial routes.Computation time increased rapidly with marker number,and 2-Opt took much less time than 3-Opt.The 2-Opt algorithm was compared with ordering methods used in two other software packages.The best method was 2-Opt using open route length as the criterion to identify the optimal order and using REC or LOD as the measure of distance between markers.We describe a unified software interface for using k-Opt in high-density linkage map construction for a wide range of genetic populations. 展开更多
关键词 OPTIMAL algorithm TRAVELING
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