Electrical pollution is a worldwide concern,because it is potentially harmful to human health.Trees not only play a significant role in moderating the climate,but also can be used as shields against electrical polluti...Electrical pollution is a worldwide concern,because it is potentially harmful to human health.Trees not only play a significant role in moderating the climate,but also can be used as shields against electrical pollution.Shielding effects on the electric field strength under transmission lines by two tree species,Populus alba and Larix gmelinii,were examined in this study.The electrical resistivity at different heights of trees was measured using a PiCUS sonic tomograph,which can image the electrical impedance for trees.The electric field strength around the trees was measured with an elf field strength measurement system,HI-3604,and combined with tree resistivity to develop a model for calculating the electric field intensity around trees using the finite element method.In addition,the feasibility of the finite element method was confirmed by comparing the calculated results and experimental data.The results showed that the trees did reduce the electric field strength.The electric field intensity was reduced by 95.6%,and P.alba was better than L.gmelinii at shielding.展开更多
The aim of this study is to present a novel semi-automatic coconut tree climbing device and validate its strength based on actual working conditions. Firstly, the structural composition and operational principal of th...The aim of this study is to present a novel semi-automatic coconut tree climbing device and validate its strength based on actual working conditions. Firstly, the structural composition and operational principal of this device is introduced. After that, the finite element model of this device is established with CATIA. Finally, the strength analysis is executed by means of CATIA. In this study, the equivalent stress, principal stress, and displacement contours are obtained. The simulation results show that the maximum stress of this device is below 355 MPa, which is the value of the yield strength. Therefore, this device is capable of satisfying practical application requirements.展开更多
基金financially supported by the National Key Research and Development Program(2017YFD0600101)the Central University Basic Research and Operating Expenses of Special Funding(2572016CB04)the Harbin Application Technology Research and Development Projects(2016RQQXJ134)
文摘Electrical pollution is a worldwide concern,because it is potentially harmful to human health.Trees not only play a significant role in moderating the climate,but also can be used as shields against electrical pollution.Shielding effects on the electric field strength under transmission lines by two tree species,Populus alba and Larix gmelinii,were examined in this study.The electrical resistivity at different heights of trees was measured using a PiCUS sonic tomograph,which can image the electrical impedance for trees.The electric field strength around the trees was measured with an elf field strength measurement system,HI-3604,and combined with tree resistivity to develop a model for calculating the electric field intensity around trees using the finite element method.In addition,the feasibility of the finite element method was confirmed by comparing the calculated results and experimental data.The results showed that the trees did reduce the electric field strength.The electric field intensity was reduced by 95.6%,and P.alba was better than L.gmelinii at shielding.
文摘The aim of this study is to present a novel semi-automatic coconut tree climbing device and validate its strength based on actual working conditions. Firstly, the structural composition and operational principal of this device is introduced. After that, the finite element model of this device is established with CATIA. Finally, the strength analysis is executed by means of CATIA. In this study, the equivalent stress, principal stress, and displacement contours are obtained. The simulation results show that the maximum stress of this device is below 355 MPa, which is the value of the yield strength. Therefore, this device is capable of satisfying practical application requirements.
