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新型悬臂式掘进机横轴截割头的研制

煤矿机械 2025年第1期46卷 60-62页

作者：董良中国煤炭科工集团太原研究院有限公司太原030006 煤矿采掘机械装备国家工程实验室太原030006 山西天地煤机装备有限公司太原030006

作为煤矿采掘机械中破岩落煤的关键部件,横轴式截割头相比纵轴式截割头在硬岩截割时具有更好的破岩效率和适应性。相比山特维克AHM105横轴截割头结构,通过在联接结构、头体结构、齿座结构、大端结构等方面的创新,采用八方结构联接、前... 详细信息

作为煤矿采掘机械中破岩落煤的关键部件,横轴式截割头相比纵轴式截割头在硬岩截割时具有更好的破岩效率和适应性。相比山特维克AHM105横轴截割头结构,通过在联接结构、头体结构、齿座结构、大端结构等方面的创新,采用八方结构联接、前后截割头体结合防剪切销组焊、J形坡口齿座、一体化耐磨头体大端等结构,成功研制了新型悬臂式掘进机横轴截割头,通过井下应用验证了该截割头在截割全岩过程中具有较高的可靠性和稳定性。研究内容为横轴式截割头的研发和创新提供了参考,具有一定的实用和推广价值。

关键词：悬臂式掘进机横轴式截割头研制

Nonlinear Performance of MEMS Vibratory Ring Gyroscope

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Acta Mechanica Solida Sinica 2021年第1期34卷 65-78页

作者： Feng liang dong-dong liang Ying-Jing Qia College of Mechanical Engineering Yangzhou UniversityYangzhou225127China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Engineering College of Mechanical Engineering and Applied ElectronicsBeijing University of TechnologyBeijing100124China

Micro-electro-mechanical system(MEMS)gyroscopes are an important sort of inertial sensor for identifying parameters of spinning structures,such as the spinning speed and angular deviation,based on the Coriolis *** this paper,the nonlinear mechanism of MEMS vibratory ring gyroscopes is analyzed by applying a fully coupled nonlinear model,in which the gyroscopic coupling and geometrically and structurally nonlinear couplings are all taken into *** coupled differential equations governing the drive and sense motions are established via the Lagrangian *** simulation is conducted,and the key nonlinear components and energy transfer behaviors between the drive and sense modes are *** is revealed that the cubic rigidity nonlinearity is another significant factor leading to the coupling between the drive and sense modes other than the gyroscopic *** analysis is also carried out by using the method of multiple *** nonlinear frequency-amplitude responses of the drive and sense vibrations are obtained,and comprehensive parametric studies are *** significant effects of system damping,excitation amplitude,drive amplitude and spinning speed on the responses are discussed,which will facilitate to improve the nonlinear performance and sensitivity of the gyroscope.

关键词： MEMS vibratory ring gyroscope Nonlinear performance Drive mode Sense mode Method of multiple scales

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Towards net zero carbon buildings:Accounting the building embodied carbon and life cycle-based policy design for Greater Bay Area,China

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Geoscience Frontiers 2024年第3期15卷 284-297页

作者： Hanwei liang Xin Bian liang dong Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Research Center of Urban Sustainable Development/School of Geographical Sciences Nanjing University of Information Science&Technology(NUIST)Nanjing 210044China Department of Architecture and Civil Engineering Chalmers University of TechnologySE-41296 GothenburgSweden Shenzhen Research Institute(SRI) City University of Hong KongShenzhenChina Department of Public and International Affairs(PIA) City University of Hong Kong999077Hong Kong Special Administrative Region School of Energy and Environment(SEE) City University of Hong Kong999077Hong Kong Special Administrative RegionChina Centre for Public Affairs and Law City University of Hong Kong999077Hong Kong Special Administrative RegionChina

Carbon mitigation of buildings is critical to promote a net-zero *** international society has vigorously promoted“Net Zero Carbon Buildings”across the globe,and accounting for building carbon emissions is critical to support this *** carbon,which represents carbon emissions from the entire lifecycle of the buildings,is fundamental for realizing the idea of zero ***,only limited studies have been conducted so far that take into account the city *** paper aimed to act as a first try to account for the embodied carbon emissions in buildings in 2020 for the Guangdong-Hong Kong Macao Greater Bay Area in China(GBA).We integrated remote sensing techniques such as night-time light data(NLT)and building material flows analysis to calculate and spatialize the newly generated building material stocks(MS).Based on the MS data,we further applied life cycle assessment(LCA)to assess the embodied carbon in the *** results highlighted that over 163 million tons of embodied carbon in buildings of GBA are expected to be generated,from 497 million tons of newly generated building MS in *** embodied carbon in each life cycle stage is valuable for further lifecyclebased policy designs for:(i)supporting the updating of the green building certification system with consideration of the embodied carbon;(ii)promoting the green building material application and certification;and(iii)reducing the embodied carbon intensity from compact urban planning policy,such as the urban agglomeration policies in *** goal of this paper was to shed a light on reducing carbon emissions from the perspective of the entire lifecycle and promote the development of net zero carbon buildings in China and Asia-Pacific.

关键词： Net zero carbon building Embodied carbon Life cycle assessment Life cycle-based policies Greater Bay area

Number of edges in inhomogeneous random graphs

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Science China Mathematics 2021年第6期64卷 1321-1330页

作者： Zhishui Hu liang dong Department of Statistics and Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China

We study the number of edges in the inhomogeneous random graph when vertex weights have an infinite mean and show that the number of edges is O(n log n).Central limit theorems for the number of edges are also establis... 详细信息

关键词： inhomogeneous random graphs number of edges power law complex network infinite mean

On stability of elastic domain during isothermal solid-solid phase transformationin a tube configuration

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Acta Mechanica Sinica 2012年第3期28卷 683-694页

作者： liang dong Qing-Ping Sun Department of Mechanical Engineering The Hong Kong University of Science and TechnologyClear Water Bay Hong Kong China

Under isothermal quasi-static stretching the phase transition of a superelastic NiTi tube involves the formation （during loading） and vanishing （in unloading） of a high strain （martensite） domain. The two events are accompanied by a rapid stress drop/rise due to the formation/vanishing of do- main fronts. From a thermodynamic point of view, both are instability phenomena that occur once the system reaches its critical state. This paper investigates the stability of a shrink- ing cylindrical domain in a tube configuration during unload- ing. The energetics and thermodynamic driving force of the cylindrical domain are quantified by using an elastic inclu- sion model. It is demonstrated that the two domain fronts ex- hibit strong interaction when they come close to each other, which brings a peak in the total energy and a sign change in the thermodynamic driving force. It is proved that such domain front interaction plays an important role in control- ling the stability of the domain and in the occurrence of stress jumps during domain vanishing. It is also shown that the pro- cess is governed by two nondimensional length scales （the normalized tube length and normalized wall-thickness） and that the length scale dependence of the critical domain length and stress jump for the domain vanishing can be quantified by the elastic inclusion model.

关键词： Cylindrical elastic domain Stability of domain Domain front Critical domain length Stress jump ~ Ther-modynamic driving force

The Number of Triangles in Random Intersection Graphs

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Communications in Mathematics and Statistics 2023年第4期11卷 695-725页

作者： liang dong Zhishui Hu International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefeiPeople’s Republic of China

Let Tn be the number of triangles in the random intersection graph G(n,m,p).When the mean of Tn is bounded,we obtain an upper bound on the total variation distance between Tn and a Poisson *** the mean of Tn tends to infinity,the Stein–Tikhomirov method is used to bound the error for the normal approximation of Tn with respect to the Kolmogorov metric.

关键词： Random intersection graph Stein’s method Poisson approximation Normal approximation

基于离散元法的水泥稳定碎石微裂细观机理研究

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土木与环境工程学报（中英文） 2025年第1期47卷 196-204页

作者：刘子龙马士宾贺苗梁栋牛宗岳河北工业大学土木与交通学院天津300401

为探究水泥稳定碎石微裂细观演化机理,构建了细观非均质水泥稳定碎石数值模型,结合室内无侧限抗压强度试验和单轴压缩数值试验反演出模型细观参数,引入微裂隙网络研究不同裂隙参数对微裂程度的影响,分析不同裂隙数目下系统能量演化规律... 详细信息

为探究水泥稳定碎石微裂细观演化机理,构建了细观非均质水泥稳定碎石数值模型,结合室内无侧限抗压强度试验和单轴压缩数值试验反演出模型细观参数,引入微裂隙网络研究不同裂隙参数对微裂程度的影响,分析不同裂隙数目下系统能量演化规律。结果表明:数值模拟与室内试验结果基本吻合,构建的水泥稳定碎石离散元模型可较为准确地表征材料细观破坏特征;微裂损伤是二次振动加载后裂隙宽度增大和裂隙数目增多共同作用的结果,裂隙密度对水泥稳定碎石微裂程度起决定性作用;裂隙密度增加,材料储存弹性应变能的能力减弱,峰值点水泥稳定碎石材料的输入总能量降低。验证了早期微裂对于降低收缩应力的积极作用,揭示了水泥稳定碎石材料微裂力学特征和细观机理。

关键词：水泥稳定碎石无侧限抗压强度离散元法微裂技术细观机理

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STRESS HYSTERESIS AND DOMAIN EVOLUTION IN THERMOELASTIC TENSION STRIPS

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Acta Mechanica Solida Sinica 2009年第5期22卷 399-406页

作者： liang dong Qingping Sun Department of Mechanical Engineering The Hong Kong University of Science and Technology Hong Kong China

Martensite domain formation, evolution and annihilation are widely observed in stress-induced phase transformation of superelastic NiTi polycrystalline shape memory alloys. By the calculation of the thermodynamic driving force and the incorporation of friction kinetics of the interface, the domain morphology and its evolution were successfully simulated by the interface-tracking technique. The computational results agree well with the experimental observation of tensile strips. Based on theoretical and computational results, we discussed the effects of critical driving force and the existence of metastability on the transition between different domain patterns.

关键词： non-convex free energy friction kinetics hysteresis metastability interface-tracking technique domain evolution