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This paper presents a detailed treatment of the formulation of static, bucking and vibration analysis of non-prismatic thin-walled composite spatial members of generic section. The theory is limited to small strains, moderate deflections and small rotations. The torsional shear strain on the middle surface of the beam wall is zero for an open contour while it corresponds to constant shear flow for a closed contour. Rigorous expressions for strains based on membrane theory of shells are obtained through which the effect of nonlinear tapering is considered. Solutions for classical buckling and vibration analysis by the finite element method are discussed. Numerical integration by using Gaussian quadrature on the cross-sections for the computation of sectorial properties and stress resultants and over the length for the computation of flexural, geometric and mass matrices is suggested. Some examples are solved and critical bucking loads, natural frequencies and the corresponding buckled and mode shapes are obtained by the Jacobi iteration procedure.

Graphics processing unit (GPU) has broad prospects in computation and memory intensive realms due to its superior performances in calculation capability, memory bandwidth and power consumption, and has natural applications in computational intensive power system analyses. Direct current power flow (DCPF) is often used in power system analysis, such as power flow analysis, security analysis and contingency screening. DCPF is a problem of solving sparse linear systems. This paper uses Jacobi iteration method to solve DCPF. Numeric studies on a 900-bus system have shown that the GPU-accelerated algorithm, in compared with its counterpart CPU version, can achieve about 2.3 times speedup. This highly promising performance has demonstrated that carefully designed performance tuning in conjunction with GPU programing architecture is imperative for a GPU-accelerated application.