Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta （L.） scale are experimentally investigated. Attention was initially directed to this problem by observation of the com...Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta （L.） scale are experimentally investigated. Attention was initially directed to this problem by observation of the complex microstrucmre of the butterfly scale as well as other studies indicating higher lift on butterfly wings covered with scale. The aerodynamic forces were measured for two oscillating scale models. Results indicated that the air cavity of an oscillating model of the Pyrameis atalanta （L.） scale increased the lift by a factor of 1.15 and reduced the damping coefficients by a factor of 1.38. The modification of the aerodynamic effects on the model of butterfly scale was due to an increase of the virtual air mass, which influenced the body. The hollow region of the scale increased the virtual air mass by a factor of 1.2. The virtual mass of the butterfly scale with the hollow region was represented as the sum of air mass of two imaginary geometrical figures： a circular cylinder around the scale and a right-angled parallelepiped within the hollow region. The interaction mechanism of the butterfly Pyrameis atalanta （L.） scale with a flow was described. This novel interaction mechanism explained most geometrical features of the airpermeable butterfly scale （inverted V-profile of the ridges, nozzle of the tip edge, hollow region, and openings of the upper lamina） and their arrangement.展开更多
Formation of hollowed village was analyzed from the perspectives of land use, infrastructure, population and industry, damages of hollowed village were proposed. Factors influencing regional applicability of the ecoto...Formation of hollowed village was analyzed from the perspectives of land use, infrastructure, population and industry, damages of hollowed village were proposed. Factors influencing regional applicability of the ecotourism renovation model for hollowed village were summarized, the evaluation index system was established according to limitation factors of the ecotourism renovation mode of hollowed village, as well as its operability and scientificity and comparable principle. On the basis of establishing the hierarchical structure and judgment matrix, weights of all indexes were defined, the indexes were graded and quantized, and finally grading standards for the regional applicability of the ecotourism renovation mode of hollowed village obtained.展开更多
文摘Questions concerning the functional role of the hollow region of the butterfly Pyrameis atalanta （L.） scale are experimentally investigated. Attention was initially directed to this problem by observation of the complex microstrucmre of the butterfly scale as well as other studies indicating higher lift on butterfly wings covered with scale. The aerodynamic forces were measured for two oscillating scale models. Results indicated that the air cavity of an oscillating model of the Pyrameis atalanta （L.） scale increased the lift by a factor of 1.15 and reduced the damping coefficients by a factor of 1.38. The modification of the aerodynamic effects on the model of butterfly scale was due to an increase of the virtual air mass, which influenced the body. The hollow region of the scale increased the virtual air mass by a factor of 1.2. The virtual mass of the butterfly scale with the hollow region was represented as the sum of air mass of two imaginary geometrical figures： a circular cylinder around the scale and a right-angled parallelepiped within the hollow region. The interaction mechanism of the butterfly Pyrameis atalanta （L.） scale with a flow was described. This novel interaction mechanism explained most geometrical features of the airpermeable butterfly scale （inverted V-profile of the ridges, nozzle of the tip edge, hollow region, and openings of the upper lamina） and their arrangement.
文摘Formation of hollowed village was analyzed from the perspectives of land use, infrastructure, population and industry, damages of hollowed village were proposed. Factors influencing regional applicability of the ecotourism renovation model for hollowed village were summarized, the evaluation index system was established according to limitation factors of the ecotourism renovation mode of hollowed village, as well as its operability and scientificity and comparable principle. On the basis of establishing the hierarchical structure and judgment matrix, weights of all indexes were defined, the indexes were graded and quantized, and finally grading standards for the regional applicability of the ecotourism renovation mode of hollowed village obtained.
