核武器是特殊的复杂系统，对使用有效性、安全性、可靠性有特殊的要求，核武器的工程研制是以科学为基础的方法进行的，强调基础应用研究，加强系统研究和计算机数值模拟。对复杂系统环境适应能力的力学和材料科学的数值模拟是重要的发展方向，数值模拟的关键建模和试验设计，目前对复杂系统还没有普适的建模理论，21世纪科学的发展，必将在各种学科领域中加快数值模拟的应用。

Nuclear weapons are complex systems with special requirements on effectiveness, safety and reliability and, therefore, science-based engineering studies have been conducted, while enhancing system engineering and computer simulation. To further study mechanics and material science for environmental adaptability of the complex systems, theoretical and computational advances must be pursued. The most important issues are theoretical modeling and test designing. Unfortunately, appropriate theories and models for complex system have not been formed yet so far. Following the science development in the 21st century, applications of computer simulations will be speed up for complex systems investigations in various disciplines.