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Geochronology,Geochemistry,and Sr-Nd-Hf Isotopes of the Diorite Porphyrites from the Weining Beishan Area,Ningxia Hui Autonomous Region:Constraints on Their Source and Tectonic Implications

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Journal of Earth Science 2024年第2期35卷 462-475页

作者： Anlu liu lianfu Hai Jinke liu Xiaojun Zhang haifeng li Fengshun Zhao Guoliang Zhao Jinhe Bai Yifu Museum China University of GeosciencesWuhan430074China School of Earth Resources China University of GeosciencesWuhan430074China Mineral Geological Survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China National Demonstration Center for Experimental Mineral Exploration Education China University of GeosciencesWuhan430074China Coal Geological Survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China Zhuhai Engineering Investigation Institute of Guangdong Province Zhuhai519000China

The Weining Beishan area of Ningxia Hui Autonomous Region is located at on the western edge of the Helanshan tectonic belt,which is a tectonic joint among Alxa Block,Ordos Block,and North Qilian orogenic belt.However,the tectonic evolution of this area remains unclear due to the lack of magmatic information.This paper conducted researches on geochronology,geochemistry,and Sr-Nd-Hf isotopes of the diorite porphyrites exposed in the Weining Beishan area.The zircon U-Pb dating yields two ages of 145.0±1.1 and 146.2±1.5 Ma,and the whole-rock geochemical data indicate that the diorite porphyrites are metaluminous to weakly peraluminous and high-K calc-alkaline series.The characteristics of highly initial^(87)Sr/^(86)Sr ratios(0.70816 to 0.71047),negativeε_(Nd)(t)(−8.9 to−8.4),and negativeε_(Hf)(t)(−13.8 to−21.2)indicate that the diorite porphyrites originated from partial melting of the middle-lower ancient crust related to the North China Craton.Combined with the regional geology,we suggested that partial melting was triggered by a tectonic activity of deep faults cutting through the crust under the regional stress transformation from compressing to extension during the Late Jurassic–Early Cretaceous,which is probably related to the westward subduction of the Paleo-Pacific Plate.

关键词： zircon U-Pb dating Sr-Nd-Hf isotopes magma source diorite porphyrite Weining Beishan area Ningxia Hui Autonomous Region geochronology geochemistry

Seismic behavior of steel tubular bridge columns equipped with low-yield-point steel plates in the root replaceable pier

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 527-548页

作者： li haifeng Jiang Kaiping Chen Yisu Han Xue College of Civil Engineering Huaqiao UniversityXiamen 361021China Key Laboratory for Intelligent Infrastructure and Monitoring of Fujian Province(Huaqiao University) Xiamen 361021China The University of New South Wales SydneyNSW 2052Australia Xiamen Institute of Technology Xiamen 361021China

To enable rapid recovery of a steel bridge column after an earthquake,a novel tubular-section steel bridge column equipped with low-yield-point(LYP)steel tubular plates in the root replaceable pier is proposed.For the purpose of discussing the seismic behavior of the novel steel bridge column,quasi-static tests and finite element simulation analyses of the specimens were carried out.The effects of parameters such as the axial compression ratio,eccentricity,and thickness and material strength of the tubular plate in the energy-dissipating zone are discussed.Experimental results from seven specimens that were subjected to four failure modes are presented.The damage to the quasi-static specimens is localized to the replaceable energy-dissipating pier.The seismic behavior of the novel steel bridge columns is significantly influenced by the axial compression ratio and eccentricity of specimens.Numerical results show that the high stress area of the specimens is mainly concentrated in the connection zone between the LYP steel tubular plate and the bottom steel plate,which is consistent with the position of the quasi-static specimen when it was prone to fracture.Finally,a calculation formula is proposed to facilitate the capacity prediction of this new steel tubular bridge column under repeated loading.

关键词： earthquake-resilient steel tubular bridge column low-yield-point steel seismic performance quasi-static test

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汽车抬头显示动态畸变的主观实验评估

光学学报 2024年第5期44卷 288-297页

作者：王韬李海峰浙江大学光电科学与工程学院极端光学技术与仪器全国重点实验室浙江杭州310027

本文建立了一种基于双目3D显示观察的主观实验流程,利用主观实验数据来分析汽车车载增强现实抬头显示(AR-HUD)设备中的动态畸变对驾驶员主观感受的影响,同时评估观看来自不同眼盒位置的图像时双目融合过程中驾驶员可以接受的畸变大小临... 详细信息

本文建立了一种基于双目3D显示观察的主观实验流程,利用主观实验数据来分析汽车车载增强现实抬头显示(AR-HUD)设备中的动态畸变对驾驶员主观感受的影响,同时评估观看来自不同眼盒位置的图像时双目融合过程中驾驶员可以接受的畸变大小临界值。实验研究结果显示,随着两眼之间的动态畸变差异的增大,驾驶员融合图像变得越来越困难,观看的不适程度也出现较快增长。同时本文也揭示了驾驶员在使用AR-HUD设备的过程中,同一眼盒两个不同位置处驾驶员可以接受的动态畸变临界条件为垂直畸变小于2%,水平畸变小于1%。此研究证实了动态畸变对驾驶员的主观感受具有较为显著的影响,并且为汽车抬头显示系统中光学设计的优化畸变过程提供了相关的数值约束参考。

关键词：动态畸变评估双目融合双目相机模型主观实验方法单因素方差分析

Petrogenesis and Geodynamic Implications of Early Cretaceous(~130 Ma)Magmatism in the Baingoin Batholith,Central Tibet:Products of Subducting Slab Rollback

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1960-1978页

作者： li Faqiao TANG Juxing WANG Nan liU Zhibo SONG Yang ZHANG Jing MA Xudong FU Bin li haifeng HAN Songhao School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia China’s 19th Metallurgical Corporation Chengdu 617000China

The Baingoin batholith is one of the largest granitic plutons in the North Lhasa terrane.Its petrogenesis and tectonic setting have been studied for decades,but remain controversial.Here we report data on geochronology,geochemistry and isotopes of Early Cretaceous granitoids within the Baingoin batholith,which provide more evidence to uncover its petrogenesis and regional geodynamic processes.The Early Cretaceous magmatism yields ages of 134.4–132.0 Ma and can be divided into I-type,S-type and highly fractionated granites.The I-and S-type granites exhibit medium SiO2,high K_(2)O/Na_(2)O with negativeεNd(t)andεHf(t)values,whereas,the albite granites have very high SiO_(2)(79.04%–80.40%),very low K_(2)O/N_(2)O,negativeεNd(t)and a large variation inεHf(t).Our new data indicate that these granitoids are derived from unbalanced melting in a heterogeneous source area.The granodiorites involved had a hybrid origin from partial melting of basalt-derived and Al-rich rocks in the crust,the porphyritic monzogranites being derived from partial melting of pelitic rocks.The albite granites crystallized from residual melt separated from K-rich magma within the‘mush’process and underwent fractionation of K-feldspar.We believe that the Early Cretaceous magmatism formed in an extensional setting produced by the initial and continuous rollback of a northward-subducting slab of the NTO.

关键词： petraluminous granites highly fractionated granites Baingoin batholith subducting slab rollback Tibet

Highly stable capacitive tactile sensors with tunable sensitivity facilitated by electrostatic interaction of layered double hydroxide,MXene,and Ag NWs

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Science China(Technological Sciences) 2023年第11期66卷 3287-3297页

作者： SHEN GengZhe HUANG WeiQing li haifeng WANG FengMing SU DaoJian li BaiJun ZHANG BoLun liANG Ping ZHANG Chi XIN Yue HE Xin School of Applied Physics and Materials Wuyi UniversityJiangmen 529020China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China

A capacitive tactile sensor(CTS)has been developed by assembling a double-sided patterned dielectric layer and novel electrodes.The patterned aluminium foil-supported electrode comprises zinc-aluminium layered double hydroxides(Zn AlLDH),MXene,and Ag NWs via electrostatic interaction.This flexible device enables greater structural deformation,thereby enhancing sensitivity to a wide range of pressure.The sensitivity of the CTS can be customized to meet specific requirements by matching the microstructured electrodes with the patterned dielectric layer.An optimized sensor exhibits a sensitivity of 2.752 kPa^(–1)within 30 kPa,a response time of approximately 100 ms,and a wide detection range of 0–300 kPa.The strong physical interaction among the electrode materials ensures a reliable conductive network,ensuring the long-term stability of the sensor,even after 7500 loading and unloading cycles.Furthermore,the fabricated CTS device presents a promising prospect for the integration into wearable electronics,with the ability to effectively respond to both human activities and external physical stimuli.

关键词： capacitive tactile sensor adjustable sensitivity long-term durability human activity monitoring

Simulation of hydraulic fracture utilizing numerical manifold method

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Science China(Technological Sciences) 2015年第9期58卷 1542-1557页

作者： ZHANG GuoXin li Xu li haifeng State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research School of Civil Engineering Beijing Jiaotong University

A 2nd order numerical manifold method(NMM) based method is developed to simulate the hydraulic fractures propagating process in rock or concrete. The proposed method uses a weak coupling technique to analyze the fluid phase and solid phase. To study the seepage behavior of the fluid phase, all the fractures in solid are identified by a block cutting algorithm and form a flow network. Then the hydraulic heads at crack ends are solved. To study the deformation and destruction of solid phase, the 2-order NMM and sub-region boundary element method are combined to solve the stress-strain field. Crack growth is controlled by the well-accepted criterion, including the tension criterion or Mohr-Coulomb criterion for the initialization of cracks and the maximum circumferential stress theory for crack propagation. Once the crack growth occurs, the seepage and deformation analysis will be resolved in the next simulation step. Such weak coupling analysis will continue until the structure becomes stable or is destructed. Five examples are used to verify the new method. The results demonstrate that the method can solve the SIFs at crack tip and fluid flow in crack network precisely, and the method is effective in simulating the hydraulic facture problem. Besides, the NMM shows great convenience and is of high accuracy in simulating the crack growth problem.

关键词：水力压裂裂缝数值流形方法 Mohr-Coulomb准则模拟裂纹扩展应力-应变场应力强度因子渗流特性

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基于U-Net的压缩光场显示图案生成方法

光学学报 2024年第10期44卷 366-384页

作者：高晨谭小地李海峰刘旭福建师范大学光电与信息工程学院福建福州350117 福建省光子技术重点实验室福建福州350117 医学光电科学与技术教育部重点实验室福建福州350117 福建省光电传感应用工程技术研究中心福建福州350117 福建师范大学信息光子学研究中心福建福州350117 浙江大学光电科学与工程学院浙江杭州310027

压缩光场显示具有结构简单紧凑、显示空间分辨率高的优点,但求解压缩光场显示图案的迭代算法存在计算量大的问题。随着人工智能技术的发展,基于深度学习的图像生成算法也被应用到三维显示中。提出一种将计算机视觉中执行图像分割任务的U... 详细信息

压缩光场显示具有结构简单紧凑、显示空间分辨率高的优点,但求解压缩光场显示图案的迭代算法存在计算量大的问题。随着人工智能技术的发展,基于深度学习的图像生成算法也被应用到三维显示中。提出一种将计算机视觉中执行图像分割任务的U-Net作为优化压缩光场显示图案的网络模型。根据给定的观看角度生成几组经过数据增强的目标光场数据集作为U-Net的训练集;在U-Net收敛后,将训练完成的U-Net用于生成重建测试目标光场的显示图案。训练和测试结果表明,相比基于堆叠CNN和迭代算法的方法,所提出的基于U-Net的压缩光场显示图案生成方法具有重建质量更高、计算资源少的优势。

关键词：物理光学成像系统压缩光场显示光场渲染深度学习

Error aware multiple vertical planes based visual localization for mobile robots in urban environments

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Science China(Information Sciences) 2015年第3期58卷 159-172页

作者： li haifeng WANG HongPeng liU JingTai College of Computer Science and Technology Civil Aviation University of China Institute of Robotics and Automatic Information System Nankai University State Key Laboratory of Robotics

A novel error-aware visual localization method is proposed that utilizes vertical planes,such as vertical building facades in urban areas as landmarks.Vertical planes,reconstructed from coplanar vertical lines,are robust high-level features if compared with point features or line features.Firstly,the error models of vertical lines and vertical planes are built,where maximum likelihood estimation(MLE)is employed to estimate all vertical planes from coplanar vertical lines.Then,the closed-form representation of camera location error variance is derived.Finally,the minimum variance camera pose estimation is formulated into a convex optimization problem,and the weight for each vertical plane is obtained by solving this well-studied problem.Experiments are carried out and the results show that the proposed localization method has an accuracy of about 2 meters,at par with commercial GPS operating in open environments.

关键词： visual localization multiple vertical planes error aware convex optimization satellite images urban environment mobile robot

Visual Localization in Urban Area Using Orthogonal Building Boundaries and a GIS Database

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机器人 2012年第5期34卷 604-613,619页

作者： li haifeng liU Jingtai LU Xiang Civil Aviation University of China Tianjin 300300 China Institute of Robotics and Automatic Information System Nankai University Tianjin 300071 China

A framework is presented for robustly estimating the location of a mobile robot in urban areas based on images extracted from a monocular onboard camera, given a 2D map with building outlines with neither 3D geometric information nor appearance data. The proposed method firstly reconstructs a set of vertical planes by sampling and clustering vertical lines from the image with random sample consensus (RANSAC), using the derived 1D homographies to inform the planar model. Then, an optimal autonomous localization algorithm based on the 2D building boundary map is proposed. The physical experiments are carried out to validate the robustness and accuracy of our localization approach.

关键词：机器人设计人工智能信息处理