分子动力学模拟中不同短程作用力计算方法的效率研究

利用分子动力学模拟的基准问题 ,对截断半径 (cut offdistance)法、Verlet链 (Verletlist)法和链格 (linked cell)法等分子间短程作用力的计算方法与模拟系统的粒子数、对比密度之间的关系进行了研究 .研究结果表明 ,各计算方法的效率与模拟系统的对比密度、粒子数量有密切关系 .在粒子数为 16 384时 ,若对比密度为 0 9,linked cell法的计算效率是截断半径法的 18倍 ,若对比密度为 0 1,两者的效率则相差 10 0倍 ;在粒子数超过 86 4以后 ,linked cell法具有明显的优势 .

Self-Organized Algorithm in LTE Networks： A Utility Function Based Optimal Power Control Scheme

In this paper, transmission power control problem for uplink LTE network is investigated and a new autonomic uplink power control scheme was proposed based on utility function, which is a self- organized algorithm. The whole approach is based on the economic concept named utility function. Then a self-organized algorithm is distributed in each mobile users to control the transmission power and to maximize the transmission utility. The proposed scheme is solved through the Lagrange multiplier technique. It is proved that the utility function based algorithm optimal power level can be model. is applicable and the achieved based on our