In this work,we used tensile tests to analyze the tangential failure forms of raw bamboo and determine a relationship between tangential tensile strength,elastic modulus,position,density,and moisture content.We found ...In this work,we used tensile tests to analyze the tangential failure forms of raw bamboo and determine a relationship between tangential tensile strength,elastic modulus,position,density,and moisture content.We found that the tangential mechanical properties of the culm wall were mainly dependent on the mechanical properties of the basic structure of the thin wall.Formulas for calculating the tangential tensile strength of moso bamboo and adjusting the moisture content were also determined.The tangential tensile strength and the tangential tensile modulus of elasticity(TTMOE)followed:outer>middle>inner,and diaphragm>bamboo node>culm wall.Below the fiber saturation point,the tangential tensile strength and TTMOE values of the bamboo gradually decreased with increasing moisture content.When the moisture content was 15%,the tangential tensile strengths of the inner,middle,outer,culm wall,bamboo node,and diaphragm samples of the five-year-old moso bamboo were 3.17,3.29,3.31,3.24,3.67,and 8.85 MPa,respectively.Furthermore,their TTMOE values were 215.09,227.98,238.45,224.04,267.21,and 559.27 MPa,respectively.Hence,this study provides a theoretical basis for future research on bamboo cracking.展开更多
A novel method is presented to build the triangular surface model and calculate the tangential stress and strain of myocardial wall ,which can be further used to reflect the left ventricle twisting—a sensitive index ...A novel method is presented to build the triangular surface model and calculate the tangential stress and strain of myocardial wall ,which can be further used to reflect the left ventricle twisting—a sensitive index to assess the systolic and diastolic function of heart. Firstly, a point distribution model is used to obtain the feature points of the ventricular surface in medical images. Secondly, the surface model is constructed by triangular mesh, and then the subdivision strategy is introduced to refine the model. Thirdly, plane projection and finite element method(FEM) are applied to calculate the tangential stress and strain.Finally, the distribution of tangential modulus of elasticity is discussed. The stimulation results show that the proposed method can be used to compute the tangential stress and strain of myocardial wall effectively and the computing result is consistent with the results mentioned in the literatures.展开更多
基金Sixth Phase of“333 Project”Training Objects in Jiangsu Province,Jiangsu Province High-Level Talent Selection Training(JNHB-127)the National Key R&D Program of China(2017YFC0703501)+3 种基金the National Natural Science Foundation of China(51878590)Jiangsu Provincial Department of Housing and Construction(2019ZD092,2020ZD40 and 2020ZD42)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20170926,BK20150878 and 20KJB560010)College Research Project(2019xjzk014)for funding this research.
文摘In this work,we used tensile tests to analyze the tangential failure forms of raw bamboo and determine a relationship between tangential tensile strength,elastic modulus,position,density,and moisture content.We found that the tangential mechanical properties of the culm wall were mainly dependent on the mechanical properties of the basic structure of the thin wall.Formulas for calculating the tangential tensile strength of moso bamboo and adjusting the moisture content were also determined.The tangential tensile strength and the tangential tensile modulus of elasticity(TTMOE)followed:outer>middle>inner,and diaphragm>bamboo node>culm wall.Below the fiber saturation point,the tangential tensile strength and TTMOE values of the bamboo gradually decreased with increasing moisture content.When the moisture content was 15%,the tangential tensile strengths of the inner,middle,outer,culm wall,bamboo node,and diaphragm samples of the five-year-old moso bamboo were 3.17,3.29,3.31,3.24,3.67,and 8.85 MPa,respectively.Furthermore,their TTMOE values were 215.09,227.98,238.45,224.04,267.21,and 559.27 MPa,respectively.Hence,this study provides a theoretical basis for future research on bamboo cracking.
基金supported by the National Natural Science Foundation of China and Microsoft Research Asia ( No. NSFC-60870002 No. 60802087)+2 种基金NCET and the Science and Technology Department of Zhejiang Province ( No. 2009C21008 No. 2010R10006 No. 2010C33095)
文摘A novel method is presented to build the triangular surface model and calculate the tangential stress and strain of myocardial wall ,which can be further used to reflect the left ventricle twisting—a sensitive index to assess the systolic and diastolic function of heart. Firstly, a point distribution model is used to obtain the feature points of the ventricular surface in medical images. Secondly, the surface model is constructed by triangular mesh, and then the subdivision strategy is introduced to refine the model. Thirdly, plane projection and finite element method(FEM) are applied to calculate the tangential stress and strain.Finally, the distribution of tangential modulus of elasticity is discussed. The stimulation results show that the proposed method can be used to compute the tangential stress and strain of myocardial wall effectively and the computing result is consistent with the results mentioned in the literatures.