The finite strip method in structural analysis has been extended, and elastic-plastic large deformation spline finite strip method based on the Updated-Lagrange method (U. L. method) was established to simulate roll f...The finite strip method in structural analysis has been extended, and elastic-plastic large deformation spline finite strip method based on the Updated-Lagrange method (U. L. method) was established to simulate roll forming process of channel section with outer edge. The deformation characteristics of strip was analyzed, and the three-dimensional displacement field, strain field and stress field of deformed strip were got. The calculation example proves that the peak transverse pressing membrane strain is on the corner part of the deformed strip, and the peak longitudinal stretching strain is on the outer edge part of the deformed strip in front of rolls. In addition, the transverse deformation of the deformed strip is principal, and the longitudinal deformation is small.展开更多
A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of ...A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of uw, and the adjacent strong edge chromatic number is defined as x'as(G) = min{k| there is a k-adjacent strong edge coloring of G}. In this paper, it has been proved that △ ≤ x'as(G) ≤ △ + 1 for outer plane graphs with △(G) ≥ 5, and X'as(G) = △ + 1 if and only if there exist adjacent vertices with maximum degree.展开更多
文摘The finite strip method in structural analysis has been extended, and elastic-plastic large deformation spline finite strip method based on the Updated-Lagrange method (U. L. method) was established to simulate roll forming process of channel section with outer edge. The deformation characteristics of strip was analyzed, and the three-dimensional displacement field, strain field and stress field of deformed strip were got. The calculation example proves that the peak transverse pressing membrane strain is on the corner part of the deformed strip, and the peak longitudinal stretching strain is on the outer edge part of the deformed strip in front of rolls. In addition, the transverse deformation of the deformed strip is principal, and the longitudinal deformation is small.
基金National Natural Science Foundation of China (No. 19871036) Qinglan talent Funds of Lanzhou Jiaotong University.
文摘A k-adjacent strong edge coloring of graph G(V, E) is defined as a proper k-edge coloring f of graph G(V, E) such that f[u] ≠ f[v] for every uv ∈ E(G), where f[u] = {f(uw)|uw ∈ E(G)} and f(uw) denotes the color of uw, and the adjacent strong edge chromatic number is defined as x'as(G) = min{k| there is a k-adjacent strong edge coloring of G}. In this paper, it has been proved that △ ≤ x'as(G) ≤ △ + 1 for outer plane graphs with △(G) ≥ 5, and X'as(G) = △ + 1 if and only if there exist adjacent vertices with maximum degree.