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多单元组合结构节点位移规格数自动生成 被引量:1
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作者 赵占朝 李桂青 +1 位作者 林家浩 李升 《工程力学》 EI CSCD 1994年第4期64-68,共5页
本文论述作为高层建筑设计TBCAD系统支撑软件的节点位移规格数自动生成的计算机方法,研制了JDPAUT程序,在DECSTATION3100上实现,并与高层建筑多重子结构分析程序DASTAB接口。
关键词 位移规格 向量空间 高层建筑 结构动力分析
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关于位移水仙花数的研究 被引量:1
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作者 杨健 韦佳玉 蒋剑军 《现代计算机》 2020年第33期30-34,43,共6页
寻找水仙花数是计算机程序设计教学中的范例。所谓水仙花数是指一个3位正整数,它各位数字的立方和等于该数本身。后来有学者将水仙花数拓展到了高位的情形。将水仙花数推广为位移水仙花数,研究位移水仙花数的性质,设计基于MATLAB矩阵运... 寻找水仙花数是计算机程序设计教学中的范例。所谓水仙花数是指一个3位正整数,它各位数字的立方和等于该数本身。后来有学者将水仙花数拓展到了高位的情形。将水仙花数推广为位移水仙花数,研究位移水仙花数的性质,设计基于MATLAB矩阵运算的位移水仙花数的快速求解算法,并对水仙花数的分类进行讨论。提出一个关于水仙花数的公开问题。当前关于水仙花数的结果是本文结果的特例。 展开更多
关键词 位移型水仙花 性质 矩阵算法 分类
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Determination of wax pattern die profile for investment casting of turbine blades 被引量:8
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作者 董一巍 卜昆 +1 位作者 窦杨青 张定华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期378-387,共10页
In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile desig... In order to conform to dimensional tolerances, an efficient numerical method, displacement iterative compensation method, based on finite element methodology (FEM) was presented for the wax pattern die profile design of turbine blades. Casting shrinkages at different positions of the blade which was considered nonlinear thermo-mechanical casting deformations were calculated. Based on the displacement iterative compensation method proposed, the optimized wax pattern die profile can be established. For a A356 alloy blade, substantial reduction in dimensional and shape tolerances was achieved with the developed die shape optimization system. Numerical simulation result obtained by the proposed method shows a good agreement with the result measured experimentally. After four times iterations, compared with the CAD model of turbine blade, the total form error decreases to 0.001 978 mm from the orevious 0.515 815 mm. 展开更多
关键词 turbine blade numerical simulation displacement field wax pattern die profile investment casting
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Safe mining technology of undersea metal mine 被引量:15
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作者 彭康 李夕兵 +2 位作者 万串串 彭述权 赵国彦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期740-746,共7页
Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and th... Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining. 展开更多
关键词 subsea bedrock mining frame stope upward horizontal slicing and filling mining method safety factor method multi-point displacement measurement
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位Love数与位移Love数之间的函数关系的注释
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作者 卢小平 张捍卫 +1 位作者 梁洪友 邓安健 《测绘科学》 CSCD 北大核心 2009年第4期36-38,共3页
固体潮Love数是表示引潮力与地球形变之间关系的参数,在地球科学中有重要应用价值。地球在各种力学机制的作用下产生了形变,形变又导致地球引力位的变化,即形变附加位或Euler引力位增量。Grafarend等基于矢量球函数的基本理论,在地球密... 固体潮Love数是表示引潮力与地球形变之间关系的参数,在地球科学中有重要应用价值。地球在各种力学机制的作用下产生了形变,形变又导致地球引力位的变化,即形变附加位或Euler引力位增量。Grafarend等基于矢量球函数的基本理论,在地球密度球对称情况下,给出了形变地球的Euler引力位增量的表达式,并利用Love-Shida假设,给出了位和位移Love数之间的函数关系。本文重新研究了Grafarend等(1997)的工作,在指出其推导过程中的一处错误后,修正了位和位移Love数的之间的函数关系。 展开更多
关键词 Euler引力位的增量 位Love 位移Love
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某水电站进水口塔基边坡地震动力响应分析
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作者 宋慧 秦永涛 《水电站设计》 2010年第3期13-16,共4页
利用Midas/GTS岩土工程有限元软件对某电站进水口边坡在塔基荷载作用下的地震动力响应进行了分析。介绍了运用Midas/GTS进行地震动力分析的方法、边界输入、加速度时程合成以及阻尼的确定等。
关键词 边坡 地震 动力特性 加速度放大系 位移数 值模拟 Midas/GTS软件
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A general method to calculate passive earth pressure on rigid retaining wall for all displacement modes 被引量:5
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作者 彭述权 李夕兵 +1 位作者 樊玲 刘爱华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1526-1532,共7页
A general analytical method to calculate the passive rigid retaining wall pressure was deduced considering all displacement modes. First, the general displacement mode function was setup, then the hypotheses were made... A general analytical method to calculate the passive rigid retaining wall pressure was deduced considering all displacement modes. First, the general displacement mode function was setup, then the hypotheses were made that the lateral passive pressure is linear to the corresponding horizontal displacement and the soil behind retaining wall is composed of a set of springs and ideal rigid plasticity body, the general analytical method was proposed to calculate the passive rigid retaining wall pressure based on Coulomb theory. The analytical results show that the resultant forces of the passive earth pressure are equal to those of Coulomb's theory, but the distribution of the passive pressure and the position of the resultant force depend on the passive displacement mode parameter, and the former is a parabolic function of the soil depth. The analytical results are also in good agreement with the experimental ones. 展开更多
关键词 rigid retaining wall displacement mode passive earth pressure parabolic function
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关于平面交叉梁系计算中的若干问题
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作者 尹德生 朱林生 李春花 《吉林建筑工程学院学报》 CAS 1996年第1期9-13,共5页
本文介绍任意平面交叉梁系结构计算的一般方法及其扩大应用,并通过算例定量地给出考虑扭矩作用时对杆件弯矩和剪力的影响.
关键词 交叉梁系 位移规格 扭角约束 井字梁
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Structures and Intermolecular Interactions in Dimethyl Sulfoxide-Water System Studied by All-atom Molecular Simulations
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作者 张荣 吴文娟 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期504-508,621,共6页
An all-atom dimethyl sulfoxide (DMSO) and water model have been used for molecular dynamics simulation. The NMR and IR spectra are also performed to study the structures and interactions in the DMSO-water system. An... An all-atom dimethyl sulfoxide (DMSO) and water model have been used for molecular dynamics simulation. The NMR and IR spectra are also performed to study the structures and interactions in the DMSO-water system. And there are traditional strong hydrogen bonds and weak C-H- ~ ~ O contacts existing in the mixtures according to the analysis of the radial distribution functions. The insight structures in the DMSO-water mixtures can be classified into different regions by the analysis of the hydrogen-bonding network. Interestingly, the molar fraction of DMSO 0.35 is found to be a special concentration by the network. It is the transitional region which is from the water rich region to the DMSO rich region. The stable aggregates of (DMSO)m'S=O…… HW-OW-(H20)n might play a key role in this region. Moreover, the simulation is compared with the chemical shifts in NMR and wavenumbers in IR with concentration dependence. And the statistical results of the average number hydrogen bonds in the MD simulations are in agreement with the experiment data in NMR and IR spectra. 展开更多
关键词 All-atom simulation Chemical shift WAVENUMBER Dimethyl sulfoxide-watersystem Hydrogen bond
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SEISMIC DAMAGE PREDICTION ON MULTI-STORYBRIOK BUILDINGS WITH TWO FRAME-SHEAR-WALL-SUPPORTED STORIES
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作者 赵彤 徐福泉 +1 位作者 郭弘 周同和 《Transactions of Tianjin University》 EI CAS 1999年第1期78-81,共4页
This paper presents a method for searching the weak story by using the ultimate shear force coefficient on the multi-story brick buildings with two frame-shear-wall-supported stories. The method of seismic damage pred... This paper presents a method for searching the weak story by using the ultimate shear force coefficient on the multi-story brick buildings with two frame-shear-wall-supported stories. The method of seismic damage prediction is discussed according to different weak stories. When the first story is t theweak one,the damage state of the building can be determined by the displacement ratio. The prediction method is also used in a practical engineering project. 展开更多
关键词 weak story seismic damage prediction displacement ratio ultimate shear force coefficient
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高精度变形测量装置
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作者 蒋树春 杨凤龙 蒋山平 《机电产品开发与创新》 2013年第5期9-10,25,共3页
论文介绍了三种高精度变形结构变形测量装置.针对不同的需求,搭建适用的测试系统,能够解决最高达CTE≤1× 10-7/deg(温度范围-10℃~45℃)内的复合材料管件轴线方向变形测量;同时针对大尺寸的变形结构件产品,也设计了最高达2μm/... 论文介绍了三种高精度变形结构变形测量装置.针对不同的需求,搭建适用的测试系统,能够解决最高达CTE≤1× 10-7/deg(温度范围-10℃~45℃)内的复合材料管件轴线方向变形测量;同时针对大尺寸的变形结构件产品,也设计了最高达2μm/1.8m×1.8m精度测试解决方案. 展开更多
关键词 高精度结构 摄影测量系统 非接触式光纤位移数测量系统 字散斑测量系统
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APPLICATION OF 2-D MOIRE INTERFEROMETRYOF STICKING FILM IN HUMAN TIBIA MEASUREMENT
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作者 张桂琴 羡若凯 《Transactions of Tianjin University》 EI CAS 1999年第1期68-71,共4页
This paper makes use of the method of testing and measuring the human body tibia by using2-D moire interferometry of sticking film. hased on the J'--y direction moire patterns recorded synchronously by 2-D optical... This paper makes use of the method of testing and measuring the human body tibia by using2-D moire interferometry of sticking film. hased on the J'--y direction moire patterns recorded synchronously by 2-D optical path,the elastic constant,strain and displacement of the tibia are measured.Compared with the electric measuring method the error is samll and the sensitivity is high. 展开更多
关键词 2-D moire interferometry of sticking film elastic constant strain and displacement
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A new analytical solution for calculation the displacement and shear stress of fully grouted rock bolts and numerical verifications 被引量:8
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作者 Ghadimi Mostafa Shariar Koroush Jalalifar Hossein 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1073-1079,共7页
In presence of difficult conditions in coal mining roadways, an adequate stabilization of the excavation boundary is required to ensure a safe progress of the construction. The stabilization of the roadways can be imp... In presence of difficult conditions in coal mining roadways, an adequate stabilization of the excavation boundary is required to ensure a safe progress of the construction. The stabilization of the roadways can be improved by fully grouted rock bolt, offering properties optimal to the purpose and versatility in use. Investigations of load transfer between the bolt and grout indicate that the bolt profile shape and spacing play an important role in improving the shear strength between the bolt and the surrounding strata. This study proposes a new analytical solution for calculation displacement and shear stress in a fully encapsulated rock bolt in jointed rocks. The main characteristics of the analytical solution consider the bolt profile and jump plane under pull test conditions. The performance of the proposed analytical solution, for three types of different bolt profile configurations, is validated by ANSYS software. The results show there is a good agreement between analytical and numerical methods. Studies indicate that the rate of displacement and shear stress from the bolt to the rock exponentially decayed. This exponential reduction in displacement and shear stress are dependent on the bolt characteristics such as: rib height, rib spacing, rib width and grout thickness, material and joint properties. 展开更多
关键词 Fully grouted bolt Jointed rock DISPLACEMENT Shear stress
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Analysis of free vibration characteristic of steel-concrete composite box-girder considering shear lag and slip 被引量:9
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作者 周旺保 蒋丽忠 余志武 《Journal of Central South University》 SCIE EI CAS 2013年第9期2570-2577,共8页
Based on Hamilton principle,the governing differential equations and the corresponding boundary conditions of steel-concrete composite box girder with consideration of the shear lag effect meeting self equilibrated st... Based on Hamilton principle,the governing differential equations and the corresponding boundary conditions of steel-concrete composite box girder with consideration of the shear lag effect meeting self equilibrated stress,shear deformation,slip,as well as rotational inertia were induced.Therefore,natural frequency equations were obtained for the boundary types,such as simple support,cantilever,continuous girder and fixed support at two ends.The ANSYS finite element solutions were compared with the analytical solutions by calculation examples and the validity of the proposed approach was verified,which also shows the correctness of longitudinal warping displacement functions.Some meaningful conclusions for engineering design were obtained.The decrease extent of each order natural frequency of the steel-concrete composite box-girder is great under action of the shear lag effect.The shear-lag effect of steel-concrete composite box girder increases when frequency order rises,and increases while span-width ratio decreases.The proposed approach provides theoretical basis for further research of free vibration characteristics of steel-concrete composite box-girder. 展开更多
关键词 steel-concrete composite box-girder shear lag effect shear deformation SLIP free vibration
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Federated UKF algorithm for mobile location estimation with TDOA/Doppler measurements 被引量:1
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作者 蔡苗红 金乐 +1 位作者 何峰 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期294-298,共5页
In order to enhance the location estimation performance of mobile station(MS)tracking and positioning, a new method of mobile location optimal estimation based on the federated filtering structure and the simplified... In order to enhance the location estimation performance of mobile station(MS)tracking and positioning, a new method of mobile location optimal estimation based on the federated filtering structure and the simplified unscented Kalman filter (UKF) is presented. The proposed algorithm uses the Singer mobile statement model as the reference system, and the simplified UKF as the subfilters. The subfilters receive the two groups of independently detected time difference of arrival (TDOA) measurement inputs and Doppler measurement inputs, and produce local estimation outputs to the main estimator. Then the main estimator performs the optimal fusion of the local estimation outputs according to the scalar weighted rule, and a global optimal or suboptimal estimation result is achieved. Finally the main estimator gives feedback and reset information to the subfilters and the reference system for next step estimation. In the simulations, the estimation performance of the proposed algorithm is evaluated and compared with the simplified UKF method with TDOA or Doppler measurement alone. The simulation results demonstrate that the proposed algorithm can effectively reduce the location estimation error and variance of the MS, and has favorable performance in both root mean square error(RMSE) and mean error cumulative distribution function(CDF). 展开更多
关键词 data fusion mobile location estimation federated filtering unscented Kalman filter(UKF)
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A displacement sensor of dual-light based on FPGA 被引量:2
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作者 HE Ming-xia ZHANG Wei-na ZHANG Xu 《Optoelectronics Letters》 EI 2007年第4期294-298,共5页
The dual-light displacement sensor is presented to obtain a higher accuracy compared with the single. The structure and principle of the system are also introduced, and the hardware and software are brought in too. Th... The dual-light displacement sensor is presented to obtain a higher accuracy compared with the single. The structure and principle of the system are also introduced, and the hardware and software are brought in too. The function of the system is feasible through the experiments and simulating the data process based on FPGA. 展开更多
关键词 位移传感器 对偶光 FPGA 据处理
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Simulation of crack coalescence mechanism underneath single and double disc cutters by higher order displacement discontinuity method 被引量:5
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作者 Mohammad Fatehi Marji 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期1045-1054,共10页
The present research is focused on the numerical crack coalescence analysis of the micro-cracks and cracks produced during the cutting action of TBM disc cutters. The linear elastic fracture mechanics(LEFM) concepts a... The present research is focused on the numerical crack coalescence analysis of the micro-cracks and cracks produced during the cutting action of TBM disc cutters. The linear elastic fracture mechanics(LEFM) concepts and the maximum tangential stress criterion are used to investigate the micro crack propagation and its direction underneath the excavating discs. A higher order displacement discontinuity method with quadratic displacement discontinuity elements is used to estimate the stress intensity factors near the crack tips. Rock cutting mechanisms under single and double type discs are simulated by the proposed numerical method.The main purposes of the present modeling are to simulate the chip formation process of indented rocks by single and double discs.The effects of specific disc parameters(except speed) on the thrust force Ft, the rolling force Fr, and the specific energy ES are investigated. It has been shown that the specific energy(energy required to cut through a unit volume of rock) of the double disc is less than that of the single disc. Crack propagation in rocks under disc cutters is numerically modeled and the optimum ratio of disc spacing S to penetration depth Pd(i.e. S/Pd ratio) of about 10 is obtained, which is in good agreement with the theoretical and experimental results cited in the literature. 展开更多
关键词 TBM disc cutter double discs cracks coalescence higher-order displacement discontinuity method specific energy
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An integrated approach to study of strata behaviour and gas flow dynamics and its application 被引量:30
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作者 Hua Guo Liang Yuan 《International Journal of Coal Science & Technology》 EI 2015年第1期12-21,共10页
This paper presents an advanced and integrated research approach to longwall mining-induced strata move- ment, stress changes, fractures, and gas flow dynamics with actual examples of its application from recent studi... This paper presents an advanced and integrated research approach to longwall mining-induced strata move- ment, stress changes, fractures, and gas flow dynamics with actual examples of its application from recent studies for coextraction of coal and methane development at Huainan Mining Group in China, in a deep and multi-seam mining environment. The advanced approach takes advantage of the latest techniques in Australia for mine scale geotechnical characterisation, field measurement, monitoring and numerical modelling. Key techniques described in this paper include coal mine site 3D geotechnical characterisation methods, surface deep downhole multi-point extensometers and piezometers for overburden displacement and pore pressure measurements during mining, tracer gas tests for goal gas flow patterns, and advanced numerical modelling codes for coupled coal mine strata, water and gas simulations, and longwall goaf gas ttow investigations. This integrated approach has resulted in significant insights into the complex dynamic imeraction between strata, groundwater, and gas during mining at Huainan Mining Group in recent years. Based on the lindings from the extensive field monitoring and numerical modelling studies, a three-dimensional annular-shaped over-lying zone along the perimeter of the longwall panel was identified for optimal methane drainage during mining. 展开更多
关键词 Co-extraction of coal and gas Strata behaviour Pore pressure Gas flow Annular overlying zone COSFLOW CFD
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Optical Fiber Instrument for Single-point Multi-parameter Measurement 被引量:1
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作者 WANGYu-tian WANGXiao-dong 《Semiconductor Photonics and Technology》 CAS 2001年第4期221-224,共4页
A novel kind of optical fiber instrument for two channel measurement of temperature and displacement was developed. Four channel quartz fiber optics were employed to measure two channel signals of temperature and disp... A novel kind of optical fiber instrument for two channel measurement of temperature and displacement was developed. Four channel quartz fiber optics were employed to measure two channel signals of temperature and displacement simultaneously, and the operating efficiency of this instrument was greatly improved. 展开更多
关键词 Fiber optics TEMPERATURE DISPLACEMENT
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Dynamic simulation on rubber spring supporting equipment of vibrating screen 被引量:3
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作者 SU Rong-hua PENG Chen-yu 《Journal of Coal Science & Engineering(China)》 2011年第2期187-191,共5页
By ANSYS, dynamic simulation analysis of rubber spring supporting equipment used in vibrating screen was made. The modal frequency, mode, and harmonic displacement under working frequency were obtained. Variation of r... By ANSYS, dynamic simulation analysis of rubber spring supporting equipment used in vibrating screen was made. The modal frequency, mode, and harmonic displacement under working frequency were obtained. Variation of rubber spring supporting equipment's dynamic performance was discussed first, which is under the condition of existing spring stiffness difference and exciting force bias. Also, the quantitative calculation formulas were given. The results indicate that the performance of vibrating screen is closely related with rubber spring supporting equipment's dynamic performance. Differences of springs' stiffness coefficients reduce the modal frequency reduced, decrease the dynamic stiffness, and increase vibration displacement. Exciting force bias induces a larger lateral displacement. When rubber springs' stiffness coefficients exist, differences and lateral force accounts for 5% in total exciting force; rubber spring supporting equipment's side swing is larger than 1 mm, exceeding the side swing limit. 展开更多
关键词 vibrating screen rubber spring dynamic simulation analysis harmonic response
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