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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Centralized Circumcentered-Reection Method for Solving the Convex Feasibility Problem in Sparse Signal Recovery
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作者 Chunmei LI Bangjun CHEN Xuefeng DUAN 《Journal of Mathematical Research with Applications》 2026年第1期119-133,共15页
Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery... Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery.We rst derive the projection formulas for a vector onto the feasible sets.The centralized circumcentered-reection method is designed to solve the convex feasibility problem.Some numerical experiments demonstrate the feasibility and e ectiveness of the proposed algorithm,showing superior performance compared to conventional alternating projection methods. 展开更多
关键词 convex feasibility problem centralized circumcentered-re ection method sparse signal recovery compressed sensing
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Numerical Simulation of the Welding Deformation of Marine Thin Plates Based on a Temperature Gradient-thermal Strain Method
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作者 Lin Wang Yugang Miao +3 位作者 Zhenjian Zhuo Chunxiang Lin Benshun Zhang Duanfeng Han 《哈尔滨工程大学学报(英文版)》 2026年第1期122-135,共14页
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t... Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates. 展开更多
关键词 Marine thin plate Welding deformation Numerical simulation Temperature gradient-thermal strain method Shell element
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基于航磁与CSAMT综合反演解释的松辽盆地东北部铀成矿构造环境研究
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作者 张翔 谢明宏 +4 位作者 张仁红 卢亚运 牛家骥 常树帅 徐顺 《矿产勘查》 2025年第6期1420-1430,共11页
松辽盆地东北部是近年来砂岩型铀矿勘查关注的重点区域,但因第四系广泛覆盖且勘查程度总体偏低,深部构造特征及其对铀成矿的制约关系亟待深入研究。针对这一关键地质问题,本文利用最新航磁数据,采用频谱分析、切线法、2.5D人机交互反演... 松辽盆地东北部是近年来砂岩型铀矿勘查关注的重点区域,但因第四系广泛覆盖且勘查程度总体偏低,深部构造特征及其对铀成矿的制约关系亟待深入研究。针对这一关键地质问题,本文利用最新航磁数据,采用频谱分析、切线法、2.5D人机交互反演和磁源参数成像(SPI)等多种技术,综合CSAMT反演结果厘定了深部构造形态与主要断裂分布,探讨了其与铀成矿的关系。研究结果表明:研究区北北东向—北东向、北西向2组深大断裂主要控制了凹凸构造形态及上白垩统分布,断陷带为古水系发育提供了有利空间,正向构造带改变了上白垩统地下水动力循环机制,有利于后生改造与含铀流体卸载成矿,克山—拜泉、明水—三道镇2片地区是铀矿勘查优先关注的地区。同时指出,在此类第四系广泛覆盖且缺少深钻孔资料的条件下,采用航磁与CSAMT综合反演解释可有效减少地球物理解释多解性,对快速解决砂岩型铀成矿宏观构造环境问题具有重要作用。 展开更多
关键词 航磁 csamt 砂岩型铀矿 松辽盆地东北部
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CSAMT在赛汉塔拉凹陷赛汉组砂体识别中的应用研究
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作者 张俊伟 孟锐 +5 位作者 张伟 焦智伟 杨晓柳 朱圣伟 赵威 高方鸿 《矿产勘查》 2025年第2期327-336,共10页
二连盆地腾格尔坳陷西部具有良好找矿远景,已发现的铀矿化赋存在下白垩统赛汉组砂体中,因此在赛汉塔拉凹陷开展了可控源音频大地电磁测量(CSAMT)。本文通过模型的正反演计算,选择初始模型为二维原始数据滑动平均模型、第一层厚度为40 m... 二连盆地腾格尔坳陷西部具有良好找矿远景,已发现的铀矿化赋存在下白垩统赛汉组砂体中,因此在赛汉塔拉凹陷开展了可控源音频大地电磁测量(CSAMT)。本文通过模型的正反演计算,选择初始模型为二维原始数据滑动平均模型、第一层厚度为40 m、圆滑系数为0.50来对原始数据进行反演处理,认为研究区下白垩统赛汉组共发育3片大规模砂体,砂体埋深及厚度由南向北逐渐增大,其最小埋深约20 m,最大埋深320 m,最大厚度为380 m,最小厚度为20 m。上述砂体整体上呈条状分布,整体较连续、稳定且规模较大,砂体物源主要来自于南部的温都尔庙隆起。通过钻孔对比及后期验证,可以看出CSAMT在该地区地层分层、砂体探测方面应用效果良好,为下一步铀矿勘查工作提供有效依据。 展开更多
关键词 csamt 铀矿勘查 模型正反演 砂体空间展布特征 赛汉塔拉凹陷
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CSAMT在胶东前垂柳矿区金矿资源调查评价中的应用 被引量:2
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作者 张利峰 段留安 +4 位作者 王志军 李子永 刘飞 王小天 韩小梦 《黄金科学技术》 北大核心 2025年第1期44-54,共11页
胶东地区是我国著名的金矿产地,是巨型矿集区。胶莱盆地东北缘位于胶东东部,广泛发育有金多金属矿床。可控源音频大地电磁法(CSAMT)具有勘探深度大、分辨率高和抗干扰能力强等特点,因此被广泛应用在矿产勘查工作中。通过在胶莱盆地东北... 胶东地区是我国著名的金矿产地,是巨型矿集区。胶莱盆地东北缘位于胶东东部,广泛发育有金多金属矿床。可控源音频大地电磁法(CSAMT)具有勘探深度大、分辨率高和抗干扰能力强等特点,因此被广泛应用在矿产勘查工作中。通过在胶莱盆地东北缘前垂柳金矿区开展可控源音频大地电磁法(CSAMT)测量工作,并结合矿区地质资料和岩石电阻率特征,查明了前垂柳矿区构造破碎带的厚度、走向以及花岗岩接触带的深部发育特征,CSAMT解译结果与钻探结果一致,取得了良好的效果,有效验证了前垂柳矿区“三层结构勘查模式”以及前垂柳一带存在“近EW向构造控矿模式”。可控源音频大地电磁法(CSAMT)可作为该区域金矿勘查的有效技术手段。 展开更多
关键词 可控源音频大地电磁法(csamt) 构造破碎带 矿产勘查 前垂柳金矿 胶莱盆地东北缘
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The Modeling of 2D Controlled Source Audio Magnetotelluric (Csamt) Responses Using Finite Element Method 被引量:1
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作者 Imran Hilman Mohammad Wahyu Srigutomo +1 位作者 Doddy Sutarno Prihadi Sumintadireja 《Journal of Electromagnetic Analysis and Applications》 2012年第7期293-304,共12页
This paper presents the modeling of 2D CSAMT responses generated by horizontal electric dipole using the separation of primary and secondary field technique. The primary field is calculated using 1D analytical solutio... This paper presents the modeling of 2D CSAMT responses generated by horizontal electric dipole using the separation of primary and secondary field technique. The primary field is calculated using 1D analytical solution for homogeneous earth and it is used to calculate the secondary electric field in the inhomogeneous Helmholtz Equation. Calculation of Helmholtz Equation is carried out using the finite element method. Validation of this modeling is conducted by comparison of numerical results with 1D analytical response for the case of homogeneous and layered earth. The comparison of CSAMT responses are also provided for 2D cases of vertical contact and anomalous conductive body with the 2D magnetotelluric (MT) responses. The results of this study are expected to provide better interpretation of the 2D CSAMT data. 展开更多
关键词 EM Modeling csamt FINITE Element method
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CSAMT技术在胶东香夼铜多金属矿勘查中的应用与研究
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作者 刘伟栋 蓝信杰 +5 位作者 张其凯 韩成 杜利明 张保涛 卢文姬 赵晓博 《中国矿业》 北大核心 2025年第S1期653-657,共5页
臧家庄盆地位于胶东北部,广泛发育铜多金属矿床,是胶东重要的多金属矿成矿带。可控源音频大地电磁测深(CSAMT)具有勘探深度大、分辨率高和受地形影响小等优点,适用于埋藏较大的矿床的找矿预测研究。通过在臧家庄盆地南缘的香夼铜多金属... 臧家庄盆地位于胶东北部,广泛发育铜多金属矿床,是胶东重要的多金属矿成矿带。可控源音频大地电磁测深(CSAMT)具有勘探深度大、分辨率高和受地形影响小等优点,适用于埋藏较大的矿床的找矿预测研究。通过在臧家庄盆地南缘的香夼铜多金属矿床开展CSAMT工作,结合矿床地质条件,利用地层与岩体的电阻率差异,推断了香夼矿床深部地质体展布特征,圈定的两个电阻率梯度带与钻探揭露结果吻合,取得较大的找矿成果,可控源音频大地电磁测深(CSAMT)可作为该区铜多金属矿勘查有效勘查方法。 展开更多
关键词 可控源音频大地电磁测深(csamt) 地质勘查方法 香夼铜多金属矿 臧家庄盆地 胶东地区
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Research on modeling source effect of 3D CSAMT based on staggered-grid finite difference method 被引量:1
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作者 ZHANG Heng LI Tonglin 《Global Geology》 2017年第1期53-58,共6页
There is usually source effect in the field work of controlled-source audio-frequency magnetotelluric method.Source effect is a thorny problem during field working,data processing and interpretation.Therefore,it is ve... There is usually source effect in the field work of controlled-source audio-frequency magnetotelluric method.Source effect is a thorny problem during field working,data processing and interpretation.Therefore,it is very important for the results of field prospecting to model source effect and summarize its influence rules.Based on the previous research,the authors use 3D finite difference method to simulate the electromagnetic field and set different anomaly situation to study the source effect in near-field measurement,then conclude the influence rules of source effect.Simulations provide the reference for the actual field work and data processing to correct the influence of source effect,so the information of the underground will be more approaching to the real. 展开更多
关键词 csamt staggered-grid f inite difference source effect three-dimensional simulation
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CSAMT法在二连盆地构造单元和砂体识别中的应用
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作者 陈功 张俊伟 艾虎 《中国矿业》 北大核心 2025年第S1期646-652,共7页
二连盆地郭尔奔地区铀成矿条件优越,发育河流沉积体系,但构造单元和目标层赛汉组砂体展布特征不明,已成为制约研究区铀矿勘查突破的瓶颈。通过在郭尔奔地区开展可控源音频大地电磁测量(CSAMT)工作,采用SCS2D软件进行电磁反演,推断了找... 二连盆地郭尔奔地区铀成矿条件优越,发育河流沉积体系,但构造单元和目标层赛汉组砂体展布特征不明,已成为制约研究区铀矿勘查突破的瓶颈。通过在郭尔奔地区开展可控源音频大地电磁测量(CSAMT)工作,采用SCS2D软件进行电磁反演,推断了找矿目标层下白垩统赛汉组砂体的空间展布特征,主要分布于伊和乌素凹陷和赛汉塔拉凹陷内,埋深135~560 m,厚80~440 m。对研究区构造单元进行了新的划分,断裂控制了构造单元边界。通过实地地质调查及后续钻孔的验证,证明了本次解释结果的准确性,为二连盆地的砂岩型铀矿勘查提供了参考与借鉴。 展开更多
关键词 csamt 下白垩统赛汉组 构造单元 砂体 二连盆地
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Three-dimensional CSAMT Forward Modeling of Potential Landslide Sliding Surfaces Using Finite Element Method
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作者 Ruo Wang Qingyun Di +3 位作者 Da Lei Changmin Fu Pengfei Liang Miaoyue Wang 《Applied Geophysics》 SCIE CSCD 2024年第4期621-638,878,共19页
Landslides are a type of natural disaster that can cause substantial harm to humanity.Monitoring and predicting the initiation of potential landslides is critical to avoiding losses due to disasters and economic activ... Landslides are a type of natural disaster that can cause substantial harm to humanity.Monitoring and predicting the initiation of potential landslides is critical to avoiding losses due to disasters and economic activities.The impact of the controlled-source audio-frequency magnetotelluric method on investigating landslide surfaces is assessed through numerical simulations with a finite element approach.A Dirichlet boundary condition is selected to match the truncated boundary,resulting in a remarkable improvement in simulation efficiency.Rederivation of the formulas for a layered medium adept to the controlled-source audiofrequency magnetotelluric method is necessary to determine the electromagnetic field at any location along the truncated boundary.After the reliability evaluation of the new codes,a landslide model with a slide surface is designed,and the characteristics of its electromagnetic field and the apparent resistivity are studied.Instead of the total electromagnetic field,which is strongly infl uenced by topography variation,the apparent resistivity should be used for sliding surface detection.The normalized pure anomalous electromagnetic field may also be employed to quickly assess the detectability of the sliding surface.Overall,this study demonstrates that the controlled-source audio-frequency magnetotelluric method can be employed for investigating landslides,and recommends survey parameters,including configuration,frequency range,and length of survey line in landslide exploration. 展开更多
关键词 csamt slide surface modeling truncated boundary survey parameters
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CSAMT法在非金属矿地质勘查中的应用——以白云敖包白云石大理岩矿床为例
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作者 王振亮 陆桂福 +5 位作者 蔡永文 龚胜平 赵克强 付燕刚 杨剑洲 高健翁 《矿产勘查》 2025年第6期1441-1450,共10页
白云敖包白云石大理岩矿床主要赋存于大豁落山组中,地表出露面积约1.1 km^(2),浅钻和刻线取样发现大豁落山组白云石大理岩达到了边界品位,单一矿体厚度大于200 m。本文通过对矿区开展CSAMT法测量,查明了白云敖包白云石大理岩矿体的埋藏... 白云敖包白云石大理岩矿床主要赋存于大豁落山组中,地表出露面积约1.1 km^(2),浅钻和刻线取样发现大豁落山组白云石大理岩达到了边界品位,单一矿体厚度大于200 m。本文通过对矿区开展CSAMT法测量,查明了白云敖包白云石大理岩矿体的埋藏深度及空间展布特征,白云石大理岩矿体在北西向长度可达1100 m,北东向长度可达1300 m,矿体最大厚度可达550 m,表明白云敖包白云石大理岩矿体规模大,具有较大的开发利用价值。CSAMT法、浅钻和刻线取样在白云敖包地区白云石大理岩矿的测量成果,为白云石大理岩矿的后续开发利用提供可靠的依据,对其他地区应用CSAMT法探测非金属矿具有参考价值和借鉴意义。 展开更多
关键词 csamt 白云石大理岩 非金属矿 内蒙古
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:5
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method 被引量:1
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作者 Chengyong Peng JianshuWu +2 位作者 Mao Jiang Biao Yin Yishan Lou 《Energy Engineering》 EI 2025年第1期185-201,共17页
To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fract... To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures. 展开更多
关键词 Hydraulic fracturing discrete element method PROPPANT SPHERICITY CFD-DEM
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Combing the Entropy Weight Method with Fuzzy Mathematics for Assessing the Quality and Post-Ripening Mechanism of High-Temperature Daqu during Storage 被引量:1
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作者 YANG Junlin YANG Shaojuan +8 位作者 WU Cheng YIN Yanshun YOU Xiaolong ZHAO Wenyu ZHU Anran WANG Jia HU Feng HU Jianfeng WANG Diqiang 《食品科学》 北大核心 2025年第9期48-62,共15页
This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standar... This study investigated the physicochemical properties,enzyme activities,volatile flavor components,microbial communities,and sensory evaluation of high-temperature Daqu(HTD)during the maturation process,and a standard system was established for comprehensive quality evaluation of HTD.There were obvious changes in the physicochemical properties,enzyme activities,and volatile flavor components at different storage periods,which affected the sensory evaluation of HTD to a certain extent.The results of high-throughput sequencing revealed significant microbial diversity,and showed that the bacterial community changed significantly more than did the fungal community.During the storage process,the dominant bacterial genera were Kroppenstedtia and Thermoascus.The correlation between dominant microorganisms and quality indicators highlighted their role in HTD quality.Lactococcus,Candida,Pichia,Paecilomyces,and protease activity played a crucial role in the formation of isovaleraldehyde.Acidic protease activity had the greatest impact on the microbial community.Moisture promoted isobutyric acid generation.Furthermore,the comprehensive quality evaluation standard system was established by the entropy weight method combined with multi-factor fuzzy mathematics.Consequently,this study provides innovative insights for comprehensive quality evaluation of HTD during storage and establishes a groundwork for scientific and rational storage of HTD and quality control of sauce-flavor Baijiu. 展开更多
关键词 microbial community high-temperature Daqu comprehensive quality evaluation entropy weight method maturation process
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In situ stress inversion using nonlinear stress boundaries achieved by the bubbling method 被引量:1
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作者 Xige Liu Chenchun Huang +3 位作者 Wancheng Zhu Joung Oh Chengguo Zhang Guangyao Si 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1510-1527,共18页
Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this cha... Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries. 展开更多
关键词 In situ stress field Inversion method The bubbling method Nonlinear stress boundary Multiple linear regression method
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CSAMT法在柴北缘绿梁山地区砂岩型铀矿勘查中的应用研究
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作者 郗昭 陈擎 +3 位作者 陈云杰 陈斌 邵恒博 吴博博 《铀矿地质》 2025年第6期1114-1125,共12页
在我国铀矿床类型中,中新生代盆地砂岩型铀矿床占据重要地位,是当前铀矿找矿工作的主要勘查方向。柴达木盆地作为我国北方重要的中新生代沉积盆地,其北缘绿梁山地区山前盆地具有砂岩型铀成矿的多种有利条件,铀成矿潜力较大,为查明柴达... 在我国铀矿床类型中,中新生代盆地砂岩型铀矿床占据重要地位,是当前铀矿找矿工作的主要勘查方向。柴达木盆地作为我国北方重要的中新生代沉积盆地,其北缘绿梁山地区山前盆地具有砂岩型铀成矿的多种有利条件,铀成矿潜力较大,为查明柴达木盆地绿梁山地区地层结构、目的层砂体的分布、厚度及埋深等,通过在该地区开展CSAMT法的井旁测深试验,并结合收集的物性资料,大致确定了区内各电性层与实际地层的对应关系及目的层砂体的电性分布情况,以此为依据对CSAMT法的测量成果进行推断解译,查明了柴达木盆地绿梁山地区发育“两隆夹一坳”的“复式”褶皱,目的层埋深最大700 m,砂体发育长度0.5~6.0 km、厚度3~300 m、埋深90~700 m。后经钻探查证,揭露多层厚大砂体,并发现铀矿化孔2个、异常孔1个,取得了较好的地质找矿线索。认为该方法可以有效地指导钻探工作部署,是开展砂岩型盆地铀矿勘查的重要技术手段之一。 展开更多
关键词 csamt 柴达木盆地 绿梁山 砂岩型铀矿
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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates
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作者 Yufeng Xing Ye Yuan Gen Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期329-355,共27页
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica... The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well. 展开更多
关键词 Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method
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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP Improved methods Field application cases
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一种基于Least Square Method算法的城轨车辆车门动作时间精准判断的研究
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作者 李宏菱 宋华杰 +3 位作者 马仲智 周辉 李晴 陈龙 《时代汽车》 2025年第3期190-192,共3页
为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波... 为研究城市轨道交通车辆客室车门动作时间精准性,门的动作主要依靠直流无刷电机的驱动,所以门动作判断的根本,是对电机运动状态的判读,门运动过程中由于电机码盘线受杂波干扰,系统无法准确寻找计时点从而影响系统判断门运动时间;建立波形矫正模型,利用数学方法校准波形,让MCU找出最佳计时点并处理(误差不超过10ms),采用最小二乘法模型,通过最小化误差的平方和找到一组数据的最佳函数匹配,求得未知的数据,并使得这些求得的数据与实际数据之间误差的平方和为最小,可精准地得到门动作时间。模拟测试结果表明,门动作时间测算误差所示其误差为7.42ms,小于10ms。 展开更多
关键词 城轨车辆 客室车门 电机码盘 Least Square method算法 门动作时间精准
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