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基于特征波导纳法和敏感性分析的大型周期支撑结构损伤识别

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振动与冲击 2017年第22期36卷 93-99页

作者：尹涛尹孟林武汉大学土木建筑工程学院武汉430072

提出了一种基于特征波导纳法和敏感性分析的大型周期支撑结构损伤识别方法。通过分析存在单一损伤单元有限周期支撑结构的自由波传播规律,建立了周期结构无量纲自振频率变化对基本周期单元刚度变化的敏感性分析矩阵;求解敏感性识别方程... 详细信息

提出了一种基于特征波导纳法和敏感性分析的大型周期支撑结构损伤识别方法。通过分析存在单一损伤单元有限周期支撑结构的自由波传播规律,建立了周期结构无量纲自振频率变化对基本周期单元刚度变化的敏感性分析矩阵;求解敏感性识别方程组,实现基于测量自振频率变化的大型周期支撑结构损伤检测;同时,分析表明所提出无量纲自振频率的敏感性与结构参数无关,即无需知道原始结构的准确几何物理参数就能确定敏感性系数。分别以一周期支撑梁与周期支撑法兰接头管道为例进行研究,表明该方法仅用量测损伤前后的前几阶自振频率变化就能较准确地进行周期支撑结构多损伤识别。

关键词：特征波导纳敏感性分析周期结构损伤识别法兰连接管道

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基于点测量的波浪确定性预报域研究

水动力学研究与进展（A辑） 2024年第2期39卷 215-226页

作者：尹孟林李金宣李美燕柳淑学大连理工大学海岸和近海工程国家重点实验室大连116024

波浪的实时预测可应用于很多领域,该文基于线性理论建立了波浪预测方法,并推导了单点测量、多点测量和移动点测量条件下,可预报域的理论范围。在此基础之上,根据物理含义给出了可预报域的判别指标能量比m0,通过物理水槽试验验证了确定... 详细信息

波浪的实时预测可应用于很多领域,该文基于线性理论建立了波浪预测方法,并推导了单点测量、多点测量和移动点测量条件下,可预报域的理论范围。在此基础之上,根据物理含义给出了可预报域的判别指标能量比m0,通过物理水槽试验验证了确定性波浪预报的效果,得出了不同波浪测量条件下,能量比m0阈值为0.01时,可预报域内计算波浪和实际波浪吻合较好。此外,还讨论了不同测量条件下,可预报域的影响因素。

关键词：波浪预报可预报域单点测量多点测量移动点测量

Seismic response control with density-variable tuned liquid dampers

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 537-546页

作者： Yuxiang Xin Genda Chen Lou menglin HNTB Corporation. 1330 Broadway. Oakland CA 94612 USA Centerfir Infrastructure Engineering Studies Misxouri University of Science and Technology Rolla M.O 65409 USA State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai China

In this paper, the seismic effectiveness of a density-variable tuned liquid damper （DVTLD） with a sloping bottom is experimentally investigated through a series of shake table tests on a 1/4-scale, 3-story frame structure and numerically simulated by a new semi-analytical model. Special attention was given to reducing the first peak and maximum response under near- and far-field ground motions, and the robustness of a density-variable control system consisting of multiple DVTLDs with closely-spaced frequencies. Adaptable to earthquake excitations, the density-variable control system has been demonstrated to be more effective and more robust than its corresponding traditional tuned liquid damper in suppressing story drift and floor acceleration of the structure. Numerical simulations of the DVTLD-controlled structure agreed very well in phase with experimental results but somewhat overestimated the amplitude of the structural response.

关键词： tuned liquid damper density-variable tuned liquid damper seismic response seismic effectivenessrobustness

NUMERICAL SOLUTION OF FLUID-STRUCTURE INTERACTION IN LIQUID-FILLED PIPES BY METHOD OF CHARACTERISTICS

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 44-49页

作者： YANG Chao YI menglin College of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China School of Mechatronic Engineering East China Jiaotong University Nanchang 330013 China College of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074. China

Fluid-structure interaction （FSI） is essentially a dynamic phenomenon and always exists in fluid-filled pipe system. The four-equation model, which has been proved to be effective to describe and predict the phenomenon of FSI due to friction coupling and Poisson coupling being taken into account, is utilized to describe the FSI of fluid-filled pipe system. Terse compatibility equations are educed by the method of characteristics （MOC） to describe the fluid-filled pipe system. To shorten computing time needed to get the solutions under the condition of keeping accuracy requirement, two steps are adopted, firstly the time step Δt and divided number of the straight pipe are optimized, sec-ondly the mesh spacing Δz close to boundary is subdivided in several submeshes automatically ac-cording to the speed gradient of fluid. The mathematical model and arithmetic are validated by com-parisons between simulation solutions of two straight pipe systems and experiment known from lit-erature.

关键词： Fluid-structure interaction Method of characteristics Coupling Fluid-filled pipe system Optimization

Structural Characteristics and Formation Dynamics: A Review of the Main Sedimentary Basins in the Continent of China

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1156-1194页

作者： HE Bizhu ZHENG menglin Institute of Geology Chinese Academy of Geological Sciences Petroleum Exploration and Development Institute Xinjiang Oilfield Company

The formation and evolution of basins in the China continent are closely related to the collages of many blocks and orogenic belts. Based on a large amount of the geological, geophysical, petroleum exploration data and a large number of published research results, the basement constitutions and evolutions of tectonic-sedimentary of sedimentary basins, the main border fault belts and the orogenesis of their peripheries of the basins are analyzed. Especially, the main typical basins in the eight divisions in the continent of China are analyzed in detail, including the Tarim, Ordos, Sichuan, Songliao, Bohai Bay, Junggar, Qiadam and Qiangtang basins. The main five stages of superimposed evolutions processes of basins revealed, which accompanied with the tectonic processes of the Paleo-Asian Ocean, Tethyan and Western Pacific domains. They contained the formations of main Cratons （1850-800 Ma）, developments of marine basins （800-386 Ma）, developments of Marine- continental transition basins and super mantle plumes （386-252 Ma）, amalgamation of China Continent and developments of continental basins （252-205 Ma） and development of the foreland basins in the western and extensional faulted basin in the eastern of China （205~0 Ma）. Therefore, large scale marine sedimentary basins existed in the relatively stable continental blocks of the Proterozoic, developed during the Neoproterozoic to Paleozoic, with the property of the intracontinental cratons and peripheral foreland basins, the multistage superimposing and late reformations of basins. The continental basins developed on the weak or preexisting divisional basements, or the remnant and reformed marine basins in the Meso-Cenozoic, are mainly the continental margins, back-arc basins, retroarc foreland basins, intracontinental rifts and pull-apart basins. The styles and intensity deformation containing the faults, folds and the structural architecture of regional unconformities of the basins, responded to the openings, subd

关键词： sedimentary basin structural architecture superimposed evolution interaction dynamics of basin and orogeny continent of China

Molecular multipoles and (hyper) polarizabilities from the Buckingham expansion:revisited

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Communications in Theoretical Physics 2020年第7期72卷 81-98页

作者： Houxian Chen menglin Liu Tianying Yan Institute of New Energy Material Chemistry School of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin 300350China

The Buckingham expansion is important for understanding molecular multipoles and(hyper)*** this study,we give a complete derivation of the Buckingham expansion in the traced form using successive Taylor *** on the derivation results,a general Buckingham expansion in the traced form is proposed,from which highly accurate numerical calculations using the finite field method can be *** transformations from the traced multipoles and multipole-multipole polarizabilities to the corresponding traceless counterparts are realized with an auxiliary traced electric field *** applications of thefinite field method in this study show good agreements with previous theoretical calculations and experimental measurements.

关键词： Buckingham expansion multipole (hyper)polarizability finite field method ab initio calculations

Light induces petal color change in Quisqualis indica(Combretaceae)

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Plant Diversity 2018年第1期40卷 28-34页

作者： Juan Yan menglin Wang Ling Zhang Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China

Petal color change, a common phenomenon in angiosperms, is induced by various environmental and endogenous factors. Interestingly, this phenomenon is important for attracting pollinators and further reproductive success. Quisqualis indica L.(Combretaceae) is a tropical Asian climber that undergoes sequential petal color change from white to pink to red. This color changing process is thought to be a good strategy to attract more pollinators. However, the underlying physiological and biochemical mechanisms driving this petal color change phenomenon is still underexplored. In this context, we investigated whether changes in pH, pollination, light, temperature or ethylene mediate petal color change. We found that the detected changes in petal pH were not significant enough to induce color alterations. Additionally, pollination and temperatures of 20-30℃did not alter the rate of petal color change; however, flowers did not open when exposed to constant temperatures at 15℃ or 35℃.Moreover, the application of ethylene inhibitor, i.e., silver thiosulphate, did not prevent color change. It is worth mentioning here that in our study we found light as a strong factor influencing the whole process of petal color change, as petals remained white under dark conditions. Altogether, the present study suggests that petal color change in Q. indica is induced by light and not by changes in petal pH, pollination, ethylene, or temperature, while extremely low or high temperatures affect flower anthesis. In summary, our findings represent the probable mechanism underlying the phenomenon of petal color change, which is important for understanding flower color evolution.

关键词： Environmental factors Ethylene Petal color pH Pollination Temperature

The Sachakou Deposit in West Kunlun of Xinjiang: A Pb-Zn Polymetallic Deposit Associated with Magmatic Metasomatism of Carbonate Rock

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 883-884页

作者： ZHOU menglin LIU yingchao School of Earth Sciences and Resources China University of Geoscience (Beijing) Institute of Geology Chinese Academy of Geological Sciences (CAGS)

Objective The Sachakou Pb-Zn polymetallic deposit is located in Hetian County, Xinjiang （geographical coordinates of E78° 57＇ 54.30＂-78°59＇ 53.63＂, N34° 39＇ 27.50＂-34° 40＇ 57.21＂）. It belongs to the West Kunlun orogenic belt on the northwest edge of the Qinghai-Tibet Plateau and is connected to the Sanjiang orogenic belt to the south （Spurlin et al., 2005）. In recent years, a series of Pb-Zn mineralized spots and deposits have been discovered in this area one after another, which is called the Huoshaoyun ore concentration area. Among them, the Sachakou Pb-Zn deposit has reserves up to140 Mt, which has reached a large scale. However, the study on the genesis of deposits in this area has only just begun. This work studied the genesis ofthis Pb-Zn deposit in order to provide new ideas for the genesis of regional deposits and regional prospecting.

关键词： Pb A Pb-Zn Polymetallic Deposit Associated with Magmatic Metasomatism of Carbonate Rock The Sachakou Deposit in West Kunlun of Xinjiang Zn

Direct Current Control Strategy of SVG Based on Dual Sequence dq Coordinates Under Asymmetric Load Condition

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Chinese Journal of Electrical Engineering 2019年第1期5卷 24-35页

作者： Shicheng Zheng Zhuangzhuang Li menglin Cao School of Electrical and information Engineering Anhui University of TechnologyMa’anshan 243002 China

In the case of asymmetric loads of power grid,load currents are composed of four components:positive sequence active and reactive components and negative sequence active and reactive components that can pollute the power grid with harmonics and reactive power and interrupt the normal operation of power ***,increasing numbers of static var generators(SVGs)are used to stabilize the power *** this study,a new type of current compensation control strategy of a three-phase three-wire SVG under an asymmetric load is *** to the symmetric component method and dual dq synchronous transformation theory,the load currents are transformed into four components under dual dq *** component is compensated separately by the ***,the proportional-limiter method is adopted to minimize the harmonics from the SVG by optimizing the waveform of the modulation wave and limiting its ***,the validity and feasibility of the control strategy are verified by simulation and experimental results.

关键词： Dual-dq transformation proportional-limiter positive and negative components active and reactive components