【摘要】 <正> 五十年代后期,美国海军特种计划局在着手制定“北极星”导弹计划时,为了实行有效的领导和管理,创造了“计划协调技术”(Program Evaluation and ReviewTechnique)即PERT。它与“临介线路法”(Critical Path Method)即CPM异曲同工地提出统筹管理的一种科学方法。由于产生了极大的经济效益而获得迅速推广,被更多还原

【Abstract】 The distribution of the random flow quantities η of an event in PERT was studied by Grubbs[4], Donaldson[6], MacCrimmon and Ryavec[5] with Beta distribution. However, in order to express the mean and standard de-viation o?this distribution by Eη=1/6(a+4m +b) and Dη=1/6(b- a), it is necessary and sufficient that p=3±2, q=3 2 or p=q=4 in Betadensity function P(x)=(x-z)p-1(b-x)q-1/(b-a)p+q-1B(p,q), where a, b and TO are theoptimistic, the pessimistic and the most likely estimation of the flow quantities, respectively. In this paper, a concentrated normal distribution function is introduced and the above mentioned distribution of the random flow quantities in the sense of approximation is treated, whereby a set of the most likely flow quantities is obtained, which is required by the projecters of PERT.更多还原