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Damage degradation mechanism and macro-meso structural response of mudstone after water wetting

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Journal of Mountain Science 2024年第8期21卷 2825-2843页

作者： SHAO Zhixin song yanqi ZHENG Junjie SHEN Fuxin LIU Chuanpeng YANG Juntao School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining&Technology(Beijing)Beijing 100083China

The predominant presence of weak interlayers primarily composed of mudstone renders them highly susceptible to a reduction in bearing capacity due to the water-rock weakening effect,significantly impacting the safety of open-pit mining *** study focuses on the weak mudstone layers within open-pit mine *** mineral composition of mudstone and the microstructure evolution characteristics before and after water wetting were analyzed by X-ray diffraction(XRD)and scanning electron microscope(SEM).The meso-structure and parameter variation characteristics of mudstone interior space after water-rock interaction were quantified by computed tomography scanning test,and the damage variable characterization method was ***,according to the uniaxial compression test,the degradation characteristics of the macroscopic mechanical behavior of mudstone under different water wetting time were explored,and the elastic modulus and strength attenuation model of mudstone based on mesoscopic damage were ***,building upon the macro-meso structural response characteristics of mudstone,an exploration of the failure characteristics and deterioration mechanism under the influence of water-rock interactions was *** results show that the water-rock interaction makes the internal defects of mudstone gradually develop and form a fracture network structure,which eventually leads to the deterioration of its macroscopic mechanical *** porosity,fractal dimension and damage characteristics of mudstone show an exponential trend with the increase of water wetting ***,the deterioration mechanism of mudstone after water wetting are postulated to encompass factors such as the hydrophilicity of mineral molecular structures,hydration stress and expansion effects on clay particles,as well as the spatial distribution of microcracks and the phenomenon of fracture *** outcomes of this research endeavor aim to provide cer

关键词： Moisture absorption of mudstone Computed tomography scanning test Fracture structure evolution Macro-meso structural response Deterioration mechanism

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Lingxiao Li Jing Li yanqi song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale MaxCut and other combinatorial optimization problems.

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单轴压缩条件下冻融灰岩裂隙扩容及损伤破坏分析

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矿业研究与开发 2024年第2期44卷 122-128页

作者：宋心怡宋彦琦马宏发杨江坤中国矿业大学(北京)力学与建筑工程学院北京100083

为研究冻融灰岩单轴压缩下裂隙应变演化及渐进损伤特征,开展了0次、10次、20次、40次灰岩冻融单轴压缩试验,建立了基于裂隙体应变特征的冻融灰岩损伤本构方程,结合PFC2D数值模拟分析了冻融灰岩的损伤破坏模式。结果表明:经历40次冻融循... 详细信息

为研究冻融灰岩单轴压缩下裂隙应变演化及渐进损伤特征,开展了0次、10次、20次、40次灰岩冻融单轴压缩试验,建立了基于裂隙体应变特征的冻融灰岩损伤本构方程,结合PFC2D数值模拟分析了冻融灰岩的损伤破坏模式。结果表明:经历40次冻融循环后,灰岩的单轴抗压强度、弹性模量、泊松比由原来的109.88 MPa、65.38 GPa、0.225分别降至70.36 MPa、46.62 GPa、0.197;冻融10次、20次、40次灰岩裂隙体应变极值分别增至0.0106, 0.0146, 0.0269。基于体积应变拐点法及位移回归分析法得到的冻融灰岩扩容应力值随冻融循环次数增加而降低,两种方法所得结果的相对误差低于10%。基于裂隙体应变特征的理论应力-应变曲线与试验曲线具有较好的一致性,所建的损伤本构方程适用于低冻融次数灰岩。基于PFC2D所得的冻融灰岩单轴压缩破坏模式为劈裂破坏和“劈裂-剪切”破坏。

关键词：冻融循环力学参数裂隙体应变扩容应力损伤本构

产业数字化如何走“实”向“深”?——数字要素全产业链溢出的内在逻辑与测算实践

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统计研究 2024年第7期41卷 29-47页

作者：马晓君宋嫣琦于渊博徐晓晴东北财经大学统计学院东北财经大学工商管理学院山东工商学院统计学院

随着数字技术的持续更新迭代,数字服务逐步推进生产管理模式向平台化、系统化变革,促使产业数字化向“技术+服务”融合赋能的模式演变。本文将产业数字化解构为数字要素的产业间价值溢出过程,运用投入产出技术定量测算数字要素溢出程度... 详细信息

随着数字技术的持续更新迭代,数字服务逐步推进生产管理模式向平台化、系统化变革,促使产业数字化向“技术+服务”融合赋能的模式演变。本文将产业数字化解构为数字要素的产业间价值溢出过程,运用投入产出技术定量测算数字要素溢出程度及驱动因素,从而基于技术、服务双维度探究数字要素赋能产业升级的内在机制,为推动现代化产业体系建设提供理论参考。研究发现,数字技术通过替代并协同传统技术推进产业升级,而数字服务通过优化中间环节进入再生产过程,实现跨部门的协同共享与资源整合,延长并创新产业链条,提升全产业链经济效率。目前国民经济各主要部门基本转向服务主导的数字化转型阶段,产业间价值联动能力显著增强,全产业数字化增量转型的链式特征逐步显现。同时,数字技术溢出受数字创新效应驱动并通过产业自主数字创新延续,数字服务溢出受需求拉动效应影响,产业间流转缓慢,产业数字化内生动力仍待开发。

关键词：产业数字化数字要素价值溢出产业链投入产出技术

Chinese herbal medicines for prostate cancer therapy: From experimental research to clinical practice

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Chinese Herbal Medicines 2023年第4期15卷 485-495页

作者： Fanming Kong Chaoran Wang Jing Zhang Xiaoqun Wang Binxu Sun Xian Xiao Haojian Zhang yanqi song Yingjie Jia Department of Oncology First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300381China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300381China Graduate School Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Traditional Chinese Medicine Tianjin Medical University General HospitalTianjin 300052China

Prostate cancer remains the second most common malignancy in men worldwide, is a global health issue,and poses a huge health burden. Precision medicine provides more treatment options for prostate cancer patients, but its popularity, drug resistance, and adverse reactions still need to be focused on. Chinese herbal medicines(CHMs) have been widely accepted as an alternative therapy for cancer, with the advantages of multiple targets, multiple pathways, and low toxicity. We searched the experimental research and clinical practice of CHMs for prostate cancer treatment published in Pub Med, Embase, and Web of Science in the last five years. We found five CHM formulas and six single CHM extracts as well as 12 CHM-derived compounds, which showed induction of apoptosis, autophagy, and cell cycle arrest, suppression of angiogenesis, proliferation, and migration of prostate cancer cells, reversal of drug resistance,and enhancement of anti-tumor immunity. The mechanisms of action include the PI3K/Akt/mTOR, AR,EGFR and Wnt/β-catenin signaling pathways, which are commonly implicated in the development of prostate cancer. We also summarized the advantages of CHMs in patients with hormone-sensitive and castration-resistant prostate cancer and provided ideas for their further experimental design and application.

关键词： Chinese herbal medicines clinical practice experimental research prostate cancer review

基于S-R和分解定理的三维几何非线性无网格法

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力学学报 2018年第4期50卷 853-862页

作者：宋彦琦周涛中国矿业大学(北京)力学与建筑工程学院北京100083

S-R(strain-rotation)和分解定理克服了经典有限变形理论的一些缺点,使其可以为几何非线性数值分析提供可靠的理论基础.对于大变形问题,由于无网格法(element-free method)避免了对单元网格的依赖,从而从根本上避免了有限单元法(finite ... 详细信息

S-R(strain-rotation)和分解定理克服了经典有限变形理论的一些缺点,使其可以为几何非线性数值分析提供可靠的理论基础.对于大变形问题,由于无网格法(element-free method)避免了对单元网格的依赖,从而从根本上避免了有限单元法(finite element method,FEM)的单元畸变问题,保证了求解精度.因此,将无网格法和S-R和分解定理结合起来势必能建立一套更加合理可靠的几何非线性数值计算方法.目前基于S-R定理的无网格数值方法研究较少并且只能用于二维平面问题的求解,但实际上绝大多数问题都必须以三维模型来进行处理,因此建立适用于三维情况的S-R无网格法是非常有必要的.本文给出了适用于三维情况的S-R无网格法:采用由更新拖带坐标法和势能率原理推导出来的增量变分方程,利用基于全局弱式的无网格Galerkin法(EFG)得到了用于求解三维空间问题的离散格式.利用MATLAB编制三维S-R无网格法程序,对受均布载荷的三维悬臂梁和四边简支矩形板结构的非线性弯曲问题进行了计算.最后将所得的数值结果与已有文献进行了比较,验证了本文的三维S-R无网格数值算法的合理性、有效性和准确性.本文的三维S-R无网格数值算法可以作为一种可靠的三维几何非线性数值分析方法.

关键词： S-R和分解三维无网格法几何非线性

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高速城市化视域下的苏南地区生态安全一体化

城市发展研究 2007年第4期14卷 59-63+108页

作者：宋言奇 215021 苏州大学社会学院江苏苏州

改革开放以来,苏南地区的城市化迅猛推进,高速城市化对区域生态安全造成了一定的威胁。在高速城市化的视域下,苏南地区苏、锡、常三市谋求生态安全不能再沿袭"画地为牢"与"独善其身"的模式,必须走一体化的道路。当前,苏南地区生态安全... 详细信息

改革开放以来,苏南地区的城市化迅猛推进,高速城市化对区域生态安全造成了一定的威胁。在高速城市化的视域下,苏南地区苏、锡、常三市谋求生态安全不能再沿袭"画地为牢"与"独善其身"的模式,必须走一体化的道路。当前,苏南地区生态安全一体化应从区域环境规划一体化、区域生态市场一体化等层面予以推进。

关键词：高速城市化苏南生态安全一体化

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基于4变量精确平板理论的剪切效应分析

应用数学和力学 2018年第11期39卷 1268-1281页

作者：周涛宋彦琦中国矿业大学(北京)力学与建筑工程学院北京100083

由于中厚板壳结构或者复合材料板壳结构中横向剪切模量与面内伸缩模量之比较低,剪切效应对其结构力学行为的影响较为严重.该文基于4变量精确平板理论(refined plate theory,RPT),对平板弯曲过程中的剪切效应进行了分析和讨论.首先对RPT... 详细信息

由于中厚板壳结构或者复合材料板壳结构中横向剪切模量与面内伸缩模量之比较低,剪切效应对其结构力学行为的影响较为严重.该文基于4变量精确平板理论(refined plate theory,RPT),对平板弯曲过程中的剪切效应进行了分析和讨论.首先对RPT进行了简要的介绍,然后以受横向均布载荷的四边简支矩形板为例,进行了无量纲的数值计算,着重讨论了平板的几何尺寸和性质对其剪切效应的影响:剪切效应随着厚度增加而加强,尤其是当宽厚比小于10以后,剪切效应会迅速加强;剪切效应随横向剪切模量与面内伸缩模量的比值减小而增强;在同种条件下,"剪切"挠度在正交各向异性板中的比重始终大于其在各向同性板中的比重,并且平板越厚或者长宽比越大,两种板的剪切效应差异性越大;各向同性板中的剪切效应受长宽比的变化表现得更加敏感,其"剪切"挠度比重随长宽比的增大而持续减小,而正交各向异性板中的"剪切"挠度比重则呈现出先减小后增大的趋势.研究结果可为提高板壳结构弯曲分析的准确性提供参考.

关键词：剪切效应剪切变形理论矩形板各向同性正交各向异性

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含不同倾角天然软弱夹层的大理岩破坏试验

中国矿业大学学报 2015年第4期44卷 623-629页

作者：宋彦琦李名刘江周涛孙川中国矿业大学(北京)理学院深部岩土力学与地下工程国家重点实验室北京100083 中国矿业大学(北京)力学与建筑工程学院北京100083

为研究不同倾角的天然软弱夹层对大理岩的影响规律,分别基于0°,30°,45°,60°和90°的天然软弱夹层岩样进行单、三轴压缩试验.试验结果表明夹层对岩石的强度具有“弱化效应”：1）单轴压缩时,夹层岩样整体上表现为劈裂型破坏,但在倾... 详细信息

为研究不同倾角的天然软弱夹层对大理岩的影响规律,分别基于0°,30°,45°,60°和90°的天然软弱夹层岩样进行单、三轴压缩试验.试验结果表明夹层对岩石的强度具有“弱化效应”：1）单轴压缩时,夹层岩样整体上表现为劈裂型破坏,但在倾斜夹层处会出现不同程度剪切滑移,产生拉剪复合型破坏.三轴压缩时,夹层岩样发生剪切破坏,其中60°夹层岩样的破裂面与夹层面完全重合.2）不同倾角的夹层对岩石的弱化作用不同,整体趋势为岩石的强度随夹层倾角的增加呈现出先减小、再增大的特点,当夹层角度为60°时,夹层对岩样的弱化效应最为显著.3）大理岩三轴压缩时沿夹层破坏的夹层倾角范围为51°～69°,理论与试验结果吻合较好。

关键词：岩石力学大理岩天然软弱夹层夹层倾角单弱面理论