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Zhiqiang Zhang Jialing Yang Hui Yu 《仿生工程学报（英文版）》2014,11(4):506-516
Cats are characterized by their excellent landing ability. During the landing, they extend and bend their flexible backs. This study was undertaken to examine the effect of flexible back on impact attenuation. We collected kinematic and ground reaction force data from cats performing self-initiated jump down at different heights. Based on these measurements, the mechanical energy and elastic back energy were calculated. Further, we derived a beam model to predict back stiffness from the morphology of the vertebral spines. We found that cat could actively modulate the bending level of flexible back and the landing angle at different heights, making some kinetic energy be stored briefly as elastic strain energy in the back. This mechanism allows cat to reduce the kinetic energy dissipated by limbs and improve the efficiency of energy absorption. These results can provide bio- logical inspiration for the design of a flexible spine on a landing robot, and we anticipated their use in the energy absorption equipments for planetary exploration. 相似文献
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大棚瓠瓜CO2加富的生理生态效应 总被引：8，自引：1，他引：7
春季对大棚瓠瓜CO2,可促进植株的生长发育,株高,茎粗增幅分别达到3．90％－19．48％和11．58％－27．37％,叶片厚度及叶面积也分别增加38．46％－69．23％和26．09％－49．38％;第一雌花着生节位平均降低2．6－4．0节,平均单果重增加4．05％－19．62％,产量 提高8．65％－19．47％,在1000μmol.mol^-1范围内,CO2浓度每增加100μmol.mol^-1,单果重和产量分别增加31．97g和68．39kg.667m^-2,第一雌花着生节位降低0．35节,在1000μmol.mol^-1浓度下,瓠瓜光合速率和羧化速率均达最高值,春季大棚瓠瓜CO2适宜施用浓度为1000μmol.mol^-1左右。 相似文献
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