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Tailoring a traditional Chinese medicine prescription for complex diseases:A novel multi-targets-directed gradient weighting strategy
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作者 Zhe Yu Teng Li +11 位作者 Zhi Zheng Xiya Yang Xin Guo Xindi Zhang Haoying Jiang Lin Zhu Bo Yang Yang Wang Jiekun Luo Xueping Yang Tao Tang En Hu 《Journal of Pharmaceutical Analysis》 2025年第4期804-816,共13页
Traditional Chinese medicine(TCM)exerts integrative effects on complex diseases owing to the characteristics of multiple components with multiple targets.However,the syndrome-based system of diagnosis and treatment in... Traditional Chinese medicine(TCM)exerts integrative effects on complex diseases owing to the characteristics of multiple components with multiple targets.However,the syndrome-based system of diagnosis and treatment in TCM can easily lead to bias because of varying medication preferences among physicians,which has been a major challenge in the global acceptance and application of TCM.Therefore,a standardized TCM prescription system needs to be explored to promote its clinical application.In this study,we first developed a gradient weighted disease-target-herbal ingredient-herb network to aid TCM formulation.We tested its efficacy against intracerebral hemorrhage(ICH).First,the top 100 ICH targets in the GeneCards database were screened according to their relevance scores.Then,SymMap and Traditional Chinese Medicine Systems Pharmacology(TCMSP)databases were applied to find out the target-related ingredients and ingredient-containing herbs,respectively.The relevance of the resulting ingredients and herbs to ICH was determined by adding the relevance scores of the corresponding targets.The top five ICH therapeutic herbs were combined to form a tailored TCM prescriptions.The absorbed components in the serum were detected.In a mouse model of ICH,the new prescription exerted multifaceted effects,including improved neurological function,as well as attenuated neuronal damage,cell apoptosis,vascular leakage,and neuroinflammation.These effects matched well with the core pathological changes in ICH.The multi-targets-directed gradient-weighting strategy presents a promising avenue for tailoring precise,multipronged,unbiased,and standardized TCM prescriptions for complex diseases.This study provides a paradigm for advanced achievements-driven modern innovation in TCM concepts. 展开更多
关键词 Traditional Chinese medicine Prescription formulation gradient weighting strategy Multiple targets Intracerebral hemorrhage
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A sharp gradient estimate for the weighted p-Laplacian 被引量:2
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作者 WANG Lin-feng ZHU Yue-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2012年第4期462-474,共13页
Let M be an n-dimensional complete noncompact Riemannian manifold with sectional curvature bounded from below, dμ = e^h(x) dV(x) the weighted measure and △μ,p the weighted p-Laplacian. In this paper we consider... Let M be an n-dimensional complete noncompact Riemannian manifold with sectional curvature bounded from below, dμ = e^h(x) dV(x) the weighted measure and △μ,p the weighted p-Laplacian. In this paper we consider the non-linear elliptic equation △μ,pu=-λμ,p|u|^p-2ufor p ∈ (1, 2). We derive a sharp gradient estimate for positive smooth solutions of this equation. As applications, we get a Harnack inequality and a Liouville type theorem.. 展开更多
关键词 weighted p-Laplacian gradient estimate Harnack inequality Liouville theorem.
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GRADIENT ESTIMATES AND ENTROPY FORMULAE FOR WEIGHTED p-HEAT EQUATIONS ON SMOOTH METRIC MEASURE SPACES 被引量:4
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作者 王宇钊 杨杰 陈文艺 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期963-974,共12页
Let (M,g, e^-fdv) be a smooth metric measure space. In this paper, we con- sider two nonlinear weighted p-heat equations. Firstly, we derive a Li-Yau type gradient estimates for the positive solutions to the followi... Let (M,g, e^-fdv) be a smooth metric measure space. In this paper, we con- sider two nonlinear weighted p-heat equations. Firstly, we derive a Li-Yau type gradient estimates for the positive solutions to the following nonlinear weighted p-heat equationand f is a smooth function on M under the assumptionthat the m-dimensional nonnegative Bakry-Emery Ricci curvature. Secondly, we show an entropy monotonicity formula with nonnegative m-dimensional Bakry-Emery Ricci curva- ture which is a generalization to the results of Kotschwar and Ni [9], Li [7]. 展开更多
关键词 gradient estimates weighted p-heat equation entropy monotonicity formula m-Bakry-t^mery Ricci curvature
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Hamilton-Souplet-Zhang's gradient estimates for two weighted nonlinear parabolic equations 被引量:1
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作者 MA Bing-qing HUANG Guang-yue 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期353-364,共12页
In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded be... In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery Ricci tensor bounded below: One is $${u_t} = {\Delta _f}u + au\log u + bu$$ with a, b two real constants, and another is $${u_t} = {\Delta _f}u + \lambda {u^\alpha }$$ with λ, α two real constants. We obtain local Hamilton-Souplet-Zhang type gradient estimates for the above two nonlinear parabolic equations. In particular, our estimates do not depend on any assumption on f. 展开更多
关键词 Hamilton’s gradient estimate Souplet-Zhang’s gradient estimate weighted nonlinear parabolic equation Bakry-Émery Ricci tensor
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Multi-Innovation Gradient Iterative Locally Weighted Learning Identification for A Nonlinear Ship Maneuvering System 被引量:3
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作者 BAI Wei-wei REN Jun-sheng LI Tie-shan 《China Ocean Engineering》 SCIE EI CSCD 2018年第3期288-300,共13页
This paper explores a highly accurate identification modeling approach for the ship maneuvering motion with fullscale trial. A multi-innovation gradient iterative(MIGI) approach is proposed to optimize the distance me... This paper explores a highly accurate identification modeling approach for the ship maneuvering motion with fullscale trial. A multi-innovation gradient iterative(MIGI) approach is proposed to optimize the distance metric of locally weighted learning(LWL), and a novel non-parametric modeling technique is developed for a nonlinear ship maneuvering system. This proposed method’s advantages are as follows: first, it can avoid the unmodeled dynamics and multicollinearity inherent to the conventional parametric model; second, it eliminates the over-learning or underlearning and obtains the optimal distance metric; and third, the MIGI is not sensitive to the initial parameter value and requires less time during the training phase. These advantages result in a highly accurate mathematical modeling technique that can be conveniently implemented in applications. To verify the characteristics of this mathematical model, two examples are used as the model platforms to study the ship maneuvering. 展开更多
关键词 multi-innovation gradient iterative(MIGI) locally weighted learning(LWL) IDENTIFICATION nonlinearship maneuvering full-scale trial
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Inversion of gravity gradient data based on spatial gradient weighting
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作者 JIANG DanDan YU Ping +1 位作者 LIN Song GAO Xiuhe 《Global Geology》 2018年第4期245-251,共7页
Compared with traditional gravity measurement data,gravity gradient tensor data contain more high frequency information,which can be used to understand the earth's interior structure,mineral resources distribution... Compared with traditional gravity measurement data,gravity gradient tensor data contain more high frequency information,which can be used to understand the earth's interior structure,mineral resources distribution etc. In this study,the authors present an algorithm for inverting gravity gradiometer data to recover the three-dimensional( 3-D) distributions of density. Spatial gradient weighting was used to constrain the extent of the body horizontally and vertically. A more accurate inversion result can be obtained by combining the prior information into the weighting function and applying it in inversion. This method was tested on synthetic models and the inverted results showed that the resolution was significantly improved. Moreover,the algorithm was applied to the inversion of empirical data from a salt dome located in Texas,USA,which demonstrated the validity of the proposed method. 展开更多
关键词 GRAVITY gradient DATA SPATIAL gradient weighting 3-D INVERSION
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深水双层管双梯度钻井流量调节与井筒压力控制研究
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作者 张政 许智博 +2 位作者 王国荣 钟林 唐洋 《中国海上油气》 北大核心 2026年第1期195-208,共14页
深水区地层普遍存在窄安全密度窗口的特性,显著增加了钻井作业中井下压力控制的难度,严重制约了深水油气资源的高效开发。针对该技术瓶颈,本文基于理论分析与数值模拟相结合的方法,系统探究了深水双层管双梯度钻井技术体系下井底压力动... 深水区地层普遍存在窄安全密度窗口的特性,显著增加了钻井作业中井下压力控制的难度,严重制约了深水油气资源的高效开发。针对该技术瓶颈,本文基于理论分析与数值模拟相结合的方法,系统探究了深水双层管双梯度钻井技术体系下井底压力动态调控机制。建立了钻井水力学参数与井底压力的耦合计算模型,分析了钻进过程中井底压力的变化规律,揭示了钻井泵排量、举升泵扬程和井底压力三者之间的关系;通过海上试验验证调节举升泵流量可精准控制钻井液当量密度,实现井底压力的主动调控。本研究通过调节举升泵流量调控井底压力,基于环空隔离液液位变化动态调整扬程,实现钻井液当量密度精准控制,以期保障深水钻井安全并支撑油气高效开发。 展开更多
关键词 深水 双梯度钻井 窄密度窗口 双层管 反循环 压力调控
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基于动态权重多指标经验回放的MADDPG算法研究
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作者 胡金泽 唐宏伟 +2 位作者 程翰超 谢培淼 贺露谊 《农业装备与车辆工程》 2026年第1期73-80,共8页
针对多智能体深度强化学习中传统经验回放机制存在的评估指标单一与权重策略静态化问题,提出一种基于动态权重多指标经验回放的改进MADDPG算法。设计了多维度经验评估体系,将时序差分误差、经验年龄和合作贡献度3个指标系统融合,实现对... 针对多智能体深度强化学习中传统经验回放机制存在的评估指标单一与权重策略静态化问题,提出一种基于动态权重多指标经验回放的改进MADDPG算法。设计了多维度经验评估体系,将时序差分误差、经验年龄和合作贡献度3个指标系统融合,实现对经验样本价值的全面评估;提出了动态权重调整机制,通过训练进程自适应的权重系数调整,使算法在训练初期注重个体价值函数准确性,后期偏向团队协作优化;构建了协作感知的优先级框架,通过合作贡献度指标显式量化经验在多智能体协作中的价值,提升团队协作效率。在OpenAI多智能体粒子环境的3个典型场景中的实验结果表明:与对比算法相比,所提算法在平均回合奖励、目标达成率与冲突规避率等关键性能指标上均有提升,收敛速度更快,验证了其有效性与优越性。 展开更多
关键词 多智能体强化学习 多智能体深度确定性策略梯度算法 经验回放 动态权重 合作贡献度 协作探索
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基于自适应联邦聚合的分层梯度裁剪算法研究
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作者 王超 李晓会 兰洁 《现代电子技术》 北大核心 2026年第5期97-101,106,共6页
针对联邦学习中数据异质性导致的模型泛化能力低以及用户隐私数据泄露问题,文中提出一种基于自适应联邦聚合的分层梯度裁剪算法。首先,根据参与方数据分布情况,利用哈达玛积更新聚合权重初始化本地模型。随后,通过预先设定的阈值,将模... 针对联邦学习中数据异质性导致的模型泛化能力低以及用户隐私数据泄露问题,文中提出一种基于自适应联邦聚合的分层梯度裁剪算法。首先,根据参与方数据分布情况,利用哈达玛积更新聚合权重初始化本地模型。随后,通过预先设定的阈值,将模型划分为个性化层和冻结层。在训练过程中,对个性化层添加扰动噪声,特别是随着网络层数的增加,扰动的幅度逐渐增大。实验结果表明,HGT-AFA在Fashion MNIST数据集上的准确率可达到91.83%,在CIFAR10数据集上的准确率可达到72.08%,有效地保证了模型的泛化性,也降低了隐私数据泄漏的风险。 展开更多
关键词 联邦学习 隐私泄露 分层梯度裁剪 自适应本地聚合 个性化层 聚合权重
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Gradient effect of road transportation on economic development in different geomorphic regions 被引量:5
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作者 YANG Xue-ting FANG Yi-ping +1 位作者 QIU Xiao-ping ZHU Fu-biao 《Journal of Mountain Science》 SCIE CSCD 2018年第1期181-197,共17页
The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan provinc... The economic benefits of transport infrastructure investment have been widely accepted.However,the varying influence of road transport development across vertical space has rarely been discussed.Taking Sichuan province in China as case study area where the landform is diverse and complex,administrative counties were categorized into 4 main types:plain counties,hill counties,mountain counties,and plateau counties.Using statistical data during 2006-2014,theperformanceofeconomic development and transport construction level in the four types of counties are discussed.Subsequently,the heterogeneous effect of each grade road on economy was calculated by local regression model(GWR).The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level,while the gradient gap among them was on the decline.Similarly,distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties.Regional imbalances were mainly reflected in the County road and Village road.Regarding the changes of regional gaps,National&Provincial roads and County roads were constantly expanding,whereas the disparity of Village road was slowly narrowing over time.Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients.On average,National&Provincial roads generated higher benefits in the high elevation regions than the lowlands.In contrast,County road and Village road were found to be more effective in promoting economic development in plains.With regard to local estimates of traffic factors,coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units.The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development. 展开更多
关键词 Geomorphic counties Road transportation Economic development Geographically weighted regression gradient variation
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The UNIFORM C^(0)ESTIMATE AND WEIGHTED ESTIMATE OF GENERALIZED CHRISTOFFEL-MINKOWSKI PROBLEMS
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作者 ZHANG Jin-hu 《数学杂志》 2024年第5期397-405,共9页
In this paper,we consider generalized Christo®el-Minkowski problems as followsσ_(k)(u_(ij)+uδ_(ij))/σ_(l)(u_(ij)+uδ_(ij))=|u^(p-1)f(x),x∈S^(n),where 0≤l≤k≤n,p-1>0 and f is positive,and we establish the... In this paper,we consider generalized Christo®el-Minkowski problems as followsσ_(k)(u_(ij)+uδ_(ij))/σ_(l)(u_(ij)+uδ_(ij))=|u^(p-1)f(x),x∈S^(n),where 0≤l≤k≤n,p-1>0 and f is positive,and we establish the weighted gradient estimate and uniform C^(0)estimate for the positive convex even solutions,which is a generalization of Guan-Xia[1]and Guan[2]. 展开更多
关键词 weighted gradient estimate convex solution minkowski type problem
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Patch-based vehicle logo detection with patch intensity and weight matrix 被引量:3
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作者 刘海明 黄樟灿 Ahmed Mahgoub Ahmed Talab 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4679-4686,共8页
A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to ... A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to bad and complex environmental conditions.The bounding-box of the logo is extracted by a thershloding approach.Experimental results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions,indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications. 展开更多
关键词 vehicle logo detection prior knowledge gradient extraction patch intensity weight matrix background removing
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Gradient Estimates for a Simple Lichnerowicz Equation on Compact Manifolds
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作者 邢杰 《Chinese Quarterly Journal of Mathematics》 2015年第3期317-322,共6页
Let(M,g) be a smooth compact Riemannian manifold of dimension n.Denote△f=△-▽f.▽ the weighted Laplacian operator,where f is a smooth real valued function on M.When N is finite and the N-Bakry-Emery Ricci tensor is ... Let(M,g) be a smooth compact Riemannian manifold of dimension n.Denote△f=△-▽f.▽ the weighted Laplacian operator,where f is a smooth real valued function on M.When N is finite and the N-Bakry-Emery Ricci tensor is bounded from below by a constant,we establish local gradient estimates for positive solutions of the following simple Lichnerowicz equation△fu+cu^(-α)=0 on a compact Riemannian manifold,where α is a positive constant and c is a smooth function. 展开更多
关键词 gradient ESTIMATE Lichnerowicz EQUATION weightED LAPLACIAN
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SOLUTIONS TO NONLINEAR ELLIPTIC EQUATIONS WITH A GRADIENT
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作者 王影 王明新 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1023-1036,共14页
In this article, we consider existence and nonexistence of solutions to problem {-△pu+g(x,u)|↓△|^p=f in -Ω,u=0 on Ω with 1〈p〈∞ where f is a positive measurable function which is bounded away from 0 in Ω,... In this article, we consider existence and nonexistence of solutions to problem {-△pu+g(x,u)|↓△|^p=f in -Ω,u=0 on Ω with 1〈p〈∞ where f is a positive measurable function which is bounded away from 0 in Ω, and the domain Ω is a smooth bounded open set in R^N(N≥2). Especially, under the condition that g(x, s) = 1/|s|^α (α〉0) is singular at s = 0, we obtain that α 〈 p is necessary and sufficient for the existence of solutions in W0^1,p(Ω) to problem (0.1) when f is sufficiently regular. 展开更多
关键词 quasilinear elliptic equations existence and nonexistence gradient terms singular weights
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基于SVM模型的亚像素位移测量方法的研究 被引量:1
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作者 沈澍 孙磊磊 +2 位作者 孙义杰 张浩 王森 《小型微型计算机系统》 北大核心 2025年第5期1156-1160,共5页
亚像素位移测量算法常见的有曲面拟合法、梯度法和插值法等,论文介绍了一种基于支持向量机(SVM)模型的亚像素位移测量方法,提出一种用于计算物体移动前后两幅图像的相关值来表征亚像素位移的梯度加权求和法.利用计算机模拟生成一系列以0... 亚像素位移测量算法常见的有曲面拟合法、梯度法和插值法等,论文介绍了一种基于支持向量机(SVM)模型的亚像素位移测量方法,提出一种用于计算物体移动前后两幅图像的相关值来表征亚像素位移的梯度加权求和法.利用计算机模拟生成一系列以0.001pixel步调的图像,其中70%作为训练集,30%作为测试集,为了检验该模型抗噪性,在生成的图像中添加不同方差的高斯噪声,并将其与曲面拟合法和梯度法进行比较,结果表明在精度要求为0.01pixel时,采用SVM法在保证高精度的情况下其抗噪性优于曲面拟合法和梯度法,其噪声方差上限为0.015,具有很好的鲁棒性可用于实际物体位移的高精度测量. 展开更多
关键词 支持向量机(SVM) 亚像素位移 数字图像相关法(DICM) 梯度加权求和法 高斯噪声
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井下煤炭运输多环节复杂背景下高精度煤矸识别方法
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作者 栾亨宣 安乐 +7 位作者 田莹 顾颉颖 张强 陈宏伟 付翔 胡成军 崔志芳 陈锐 《煤炭科学技术》 北大核心 2025年第9期459-468,共10页
煤矸智能分选是发展煤炭智能绿色开采的关键技术之一。准确识别煤矸石是智能分选的先决条件,如何克服井下复杂环境的影响,已成为影响机器视觉识别效果的现实难题。针对井下煤炭运输系统,构建具有单一、二混合和三混合背景的11类图像数据... 煤矸智能分选是发展煤炭智能绿色开采的关键技术之一。准确识别煤矸石是智能分选的先决条件,如何克服井下复杂环境的影响,已成为影响机器视觉识别效果的现实难题。针对井下煤炭运输系统,构建具有单一、二混合和三混合背景的11类图像数据集,包含水渍、煤粉、碎煤与碎矸石及运输设备部件等背景干扰因素。提出了一种融合多种注意力与残差连接的高精度煤矸智能识别方法,高分辨率阶段使用残差卷积块快速生成高质量标记(token),后续阶段使用级联的Channel Spatial Swin Transformer Block(CSSTB)进行深层表征学习。为提升模型对背景噪声的抗干扰能力,网络集成全局、通道、空间多种注意力机制,增强特征表达的鲁棒性。CSSTB中利用基于负斜率特性强化稀疏激活的LeakyReLU线性注意力机制建模全局信息,通过卷积注意力机制模块(CBAM)优化模型注意力分布,提升模型泛化能力。此外,考虑到煤、矸石和输送设备零部件的尺度差异,跨阶段使用残差连接以增强多尺度特征的通信和信息流通。结果表明:所提模型在单一、二混合和三混合背景上的平均准确度达到95.06%、97.77%、95.65%,相较于基线网络Swin Transformer-Tiny分别提高7.01%、4.83%、1.03%。可视化试验表明,对比模型在水渍、暗光和反光等复杂背景干扰下难以准确区分煤和矸石,而所提出模型能够精准聚焦于煤和矸石的关键特征区域,抗干扰能力强。研究结果为井下原煤运输中的煤矸高效分选提供了理论参考。 展开更多
关键词 深度学习 煤矸识别 井下环境 注意力机制 梯度加权类激活热图
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共同富裕水平的评价与预测——基于机器学习算法 被引量:4
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作者 薛洁 武欣妍 《调研世界》 2025年第4期17-32,共16页
共同富裕是社会主义的本质要求,研究2016—2022年共同富裕在全国31个省(区、市)的发展,对于全面建成社会主义现代化强国有参考作用。本文从经济质量、协调发展、生活丰富、社会稳定、公共服务、美丽家园等六个方面,选择41个评价指标,构... 共同富裕是社会主义的本质要求,研究2016—2022年共同富裕在全国31个省(区、市)的发展,对于全面建成社会主义现代化强国有参考作用。本文从经济质量、协调发展、生活丰富、社会稳定、公共服务、美丽家园等六个方面,选择41个评价指标,构建共同富裕评价指标体系,并利用CRITIC权重法对各省(区、市)发展水平进行测算,采用K-Means++聚类算法对一级指标得分结果进行等级分类。随后创新性地通过梯度提升算法对各省(区、市)共同富裕发展水平等级进行预测。研究结果表明:(1)2016—2022年,我国共同富裕发展水平从东至西呈现“高—中—低”阶梯式分布,但贫富差距显著缩小;(2)结合梯度提升算法研究我国共同富裕发展水平效果较好,其中XGBoost分类算法的预测结果最优。基于研究结论,本文分别从经济质量、协调发展、公共服务等方面提出政策建议,以期对推动共同富裕发展及后续相关研究提供参考。 展开更多
关键词 共同富裕 CRITIC权重法 K-Means++聚类算法 梯度提升算法
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基于多传感器融合的液压支架位姿精确感知方法 被引量:2
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作者 马长青 李旭阳 +3 位作者 李峰 毛俊杰 魏祥宇 马肖杨 《工矿自动化》 北大核心 2025年第4期114-119,共6页
为精确感知扰动环境下液压支架位姿信息,提出了一种基于多传感器融合的液压支架位姿精确感知方法。首先,在液压支架顶梁、掩护梁、后连杆和底座4个构件上部署九轴姿态传感器,利用其陀螺仪、加速度计和磁力计分别解算出其所在构件的横滚... 为精确感知扰动环境下液压支架位姿信息,提出了一种基于多传感器融合的液压支架位姿精确感知方法。首先,在液压支架顶梁、掩护梁、后连杆和底座4个构件上部署九轴姿态传感器,利用其陀螺仪、加速度计和磁力计分别解算出其所在构件的横滚角、俯仰角和偏航角等位姿数据;然后,通过无迹卡尔曼滤波(UKF)算法和梯度下降(IGD)算法(IGD-UKF算法)对位姿数据进行滤波处理,降低扰动因素对位姿数据的干扰;最后,采用自适应加权融合算法对滤波处理后的液压支架顶梁和底座的偏航角和横滚角数据进行融合处理,消除外界振动、噪声等因素引起的液压支架顶梁和底座传感器数据误差。对施加扰动下液压支架顶梁低头和抬头、底座低头和抬头、液压支架左倾和右倾、液压支架左偏和右偏等工况下顶梁、掩护梁、后连杆和底座的位姿进行感知实验,结果表明:经IGD-UKF算法处理后的数据曲线波动趋于平缓,在抑制振荡、减小振幅上的效果明显;液压支架偏航角误差为0.001 8~0.025 1°,平均绝对误差为0.004 8°,横滚角误差为0.001 4~0.028 1°,平均绝对误差为0.004 7°,实现了扰动环境下液压支架位姿的精确感知。 展开更多
关键词 液压支架 支架位姿感知 多传感器融合 无迹卡尔曼滤波 梯度下降 自适应加权融合 九轴姿态传感器
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基于夜间灯光数据的黄河流域城市建设用地碳排放影响因素分析及达峰预测
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作者 薛建春 曹凌辰 +1 位作者 张翔 丁志斌 《沈阳农业大学学报》 北大核心 2025年第3期148-162,共15页
[目的]利用夜间灯光数据与省域CEADs碳排放构建拟合模型,计算黄河流域2000–2022年各地级市的城市建设用地碳排放。[方法]使用标准差椭圆以及重心模型分析探索黄河流域城市建设用地碳排放分布重心和重心移动趋势,通过全局莫兰指数和LIS... [目的]利用夜间灯光数据与省域CEADs碳排放构建拟合模型,计算黄河流域2000–2022年各地级市的城市建设用地碳排放。[方法]使用标准差椭圆以及重心模型分析探索黄河流域城市建设用地碳排放分布重心和重心移动趋势,通过全局莫兰指数和LISA集聚分析其空间相关性与高值聚集情况,最后利用GTWR模型从经济、人口、技术的角度分析各城市建设用地碳排放影响因素的回归系数水平,采用情景设定法探索不同情景下黄河流域建设用地“碳达峰”情况。[结果]黄河流域城市建设用地碳排放主要集中在下游、中游城市,但碳排放重心有向中游移动的趋势,坐标由111°82′81″E、37°01′675″N转移至111°56′46″E、36°53′425″N。同时碳排放在黄河流域内存在空间自相关性,下游地区部分城市存在高高集聚的现象。研究时期内,经济发展水平的回归系数逐渐减小,但在中游地区逐渐增加;人口规模的回归系数逐渐增大,说明由人口规模引发的碳排放量逐渐增大。[结论]经济高速发展情景下,建设用地“碳达峰”时间为2030年,基准与低碳发展情景下建设用地“碳达峰”时间均为2024年,峰值由大到小为:高速发展>基准>低碳情景。 展开更多
关键词 黄河流域 城市建设用地碳排放 影响因素 空间自相关模型 GTWR XGBoost
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地理加权梯度提升机模型在黑龙江省林火预测中的应用
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作者 倪荣雨 李春辉 +4 位作者 欧阳逸云 王文龙 张金文 郭福涛 苏漳文 《生态学报》 北大核心 2025年第22期11257-11267,共11页
林火作为全球变化背景下重要的生态干扰因子,不仅影响森林生态系统结构与功能,还对区域气候、碳循环及人类活动构成威胁。因此,科学准确地预测林火发生概率并识别其主导影响因子,对于预防和减缓其危害至关重要。以黑龙江省为研究区,基于... 林火作为全球变化背景下重要的生态干扰因子,不仅影响森林生态系统结构与功能,还对区域气候、碳循环及人类活动构成威胁。因此,科学准确地预测林火发生概率并识别其主导影响因子,对于预防和减缓其危害至关重要。以黑龙江省为研究区,基于2006—2020年火点数据,结合气象、地形、植被、人为活动和社会基础设施五类共15个影响因子,分别构建全局梯度提升机模型(Gradient Boosting Machine,GBM)与地理加权梯度提升机模型(Geographically Weighted GBM,GWGBM),以探讨不同模型在林火发生概率预测中的表现差异,并识别主要驱动因素及其空间异质性特征。结果显示,相较于GBM模型,GWGBM模型在捕捉林火发生的空间异质性与因子间非线性关系方面具有更强能力,其测试集准确率提高25%。同时,结果表明黑龙江省林火受多因素综合作用影响,其中气候条件与植被因素为主要林火驱动因子。模型预测的火险概率空间分布与历史林火热点区域高度吻合,具备良好的现实指导价值。本研究验证了将地理加权思想引入梯度提升建模的可行性与有效性,为林火空间概率建模提供了新路径。在实际应用中,GWGBM模型可用于辅助制定分区域、分等级的林火防控策略。未来研究可进一步引入时间维度,构建时空加权模型,探索气候变化背景下林火风险的动态演变过程,并考虑不同空间尺度下模型精度的敏感性分析,以实现更加全面和精细的林火管理与决策支持。 展开更多
关键词 林火预测 梯度提升机 地理加权梯度提升机 黑龙江
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