不論初始值的猜測值如何，基因法則總會收斂至整體的極值(global extreme)，因此，在數值模擬顯示中，即時最初的猜測值與實際值相距甚遠，最終我們依然可求得準確的數值解，成功的重建物體形狀函數。而在數值模擬顯示中，量測的散射場即使加入高斯分佈的雜訊，依然可以得到良好的重建結果，研究證實其有良好的抗雜訊能力。 In this paper, we present a computational approach to the imaging of a partially immersed perfectly conducting cylinder by the steady-state genetic algorithm. A conducting cylinder of unknown shape scatters the incident transverse electric (TE) wave in free space while the scattered field is recorded outside. Based on the boundary condition and the measured scattered field, a set of nonlinear integral equations is derived and the imaging problem is reformulated into an optimization problem. An improved steady-state genetic algorithm is employed to search for the global extreme solution. Numerical results demonstrate that, even when the initial guess is far away from the exact one, good reconstruction can be obtained.