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In order to consider the effect of non-coincidence of torsion center and gravity center,the rectangular variable-curvature-box girder with vertical symmetrical axis is studied. Considering the influence of shear deflection and non-coincidence of torsion center and gravity center, the elastic equilibrium formulas are established. Based on deformation equations of the girder and the relations of inner forces and deformations,the flexure-torsion differential equations are developed. The equilibrium differential equations and Galerkin methods formulas for clothoid curved box girder are presented. 相似文献
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The design of multi-controller and multi-mode control law is presented for the three-link Acrobot on horizontal bar by employing Human simulated intelligent control method based on sensory-motor Schema.Imitated the characteristics of gymnast's swing-up and handstand movement,the control process of robot is divided by six sequence phase.Then the sensory cell and motor cell and the group of sensory-motor schema is designed based on the analysis of quality-quantity combination.The simulation results show that the controller ensures the gesture and the energy to the desired goal,farther more the motion control of giant swing backword is realized in the simulation. 相似文献
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A new type of inorganic anchoring material is developed as a substitution for anchoring adhesive to overcome some imperfections in the process of planting reinforcing steel bar.The mix proportion of the anchoring material is determined by experiments.The compressive strength,adhesive force to concrete,volume stability and anchoring force with steel bar are studied.The early strength of the anchoring inorganic material is quite high: for 1d up to 38.5MPa and 3d up to 60MPa.It is a good adhesive to concrete and the adhesive strength of 28d is about 2MPa.The anchoring material will have tiny volume expansion with the age,which is beneficial to enhancing the anchoring force.The essential component of the inorganic anchoring material is cement-based material,so some defects of the organic macromolecular material can be avoided,such as poor stability and requirement for vigorous construction conditions.Its characteristics in early strength,adhesive force to concrete and volume expansion can satisfy the requirement of the construction to the planting reinforcing steel bar and the loading force,thus it can be used as a substituting material for anchoring adhesive. 相似文献
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The torsion vibration of main transmission system of 1 450 rolling mill is tested:The torsion vibration frequency and amplification coefficient of torque are obtained.Basing on part of the measured date and theoretical analysis,the measure is developed for preventive method;it is of important theoretic sense and high engineering practical value for reducing accident and controlling torsion vibration. 相似文献
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Microstructures, Reaction Kinetics and Properties of Reaction Between Magnesium and Silica Glass 下载免费PDF全文
In earlier calculation models,the stiffness centers in frame-shear wall structures have been located by the structural torsion stiffness.However,the results are illogical owing to the difference between the distortion character and the shears distribute mechanism of the frames and shear walls.In this paper,a new formula for calculating story stiffness is introduced,which can consider the stiffness of the frames and shear walls at the same time.The structural stiffness centers,the torsion eccentric distances and torsion effect are calculated,and the stiffness of elements is considered also.It is shown that the concept of the presented stiffness model is clear and the results are reasonable,which can be used to calculate the appreciative torsion effect. 相似文献
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Pushover analysis is a tool to study the inelastic behavior of structures under strong seismic action. The 3D-pushover analysis was performed to analyze the inelastic lateral-torsional coupled response of multistory asymmetric structures. The symmetric frame and frame-wall systems were studied in this paper, and the capability curve of the top displacement and base shear,the story drift and the position of rotation center were compared with reference to corresponding symmetric structures. The characters of inelastic response of multistory asymmetric structures were found. The conclusion provides reference for performance-based seismic design of asymmetric structures. 相似文献
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利用数码相机获取棒材端面的图像,通过对图像格式转化、灰度化处理得到灰度图像,再进行平滑处理抑制噪声、锐化处理突出目标、选择合适的闻值转换为二值图像,然后进行形态学腐蚀操作去掉棒材之间的粘连,最终得到分割效果较好的图像,为后续棒材的计数奠定了基础。 相似文献