When analyze the uncertainty of the cost and the schedule of the spaceflight project, it is needed to know the value of the schedule-cost correlation coefficient. This paper deduces the schedule distribution, consider...When analyze the uncertainty of the cost and the schedule of the spaceflight project, it is needed to know the value of the schedule-cost correlation coefficient. This paper deduces the schedule distribution, considering the effect of the cost, and proposes the estimation formula of the correlation coefficient between the in（schedule） and the cost. On the basis of the fact and Taylor expansion, the relation expression between the schedule-cost correlation coefficient and the in-schedule-cost correlation coefficient is put forward. By analyzing the value features of the estimation formula of the in-schedule-cost correlation coefficient, the general rules are proposed to ascertain the value of the schedule-cost correlation coefficient. An example is given to demonstrate how to approximately amend the schedule-cost correlation coefficient based on the historical statistics, which reveals the traditional assigned value is inaccurate. The universality of this estimation method is analyzed.展开更多
On September 21,1992, the feasibility report on implementing China's Manned Spaceflight Project was approved and a three-step development strategy was also determined. From then on, China's Manned Spaceflight ...On September 21,1992, the feasibility report on implementing China's Manned Spaceflight Project was approved and a three-step development strategy was also determined. From then on, China's Manned Spaceflight Project has developed rapidly.展开更多
To evaluate the cost risk and the schedule risk of the spaceflight project,the schedule-cost(S-C) correlation coefficient is directly appointed according to the experts' experience usually.This paper deduces SDMCU...To evaluate the cost risk and the schedule risk of the spaceflight project,the schedule-cost(S-C) correlation coefficient is directly appointed according to the experts' experience usually.This paper deduces SDMCU(the schedule distribution model considering the effect of the cost uncertainty),and then proposes the approximate formula to estimate the ln(S)-C correlation coefficient based on the models of SDMCU and CDMSU(the cost distribution model considering the effect of the schedule uncertainty).Furthermore,an approximate relationship expression of the S-C and the ln(S)-C correlation coefficients is put forward according to general facts and the Taylor expansion,and advanced by means of mass numerical validation is the general rule of obtaining the estimation value of the schedule-cost correlation coefficient based on the historical data.展开更多
基金This project was supported by Weapon System Advanced Research Foundation(51419010204KG01) and National ScienceFoundation of China(70272002).
文摘When analyze the uncertainty of the cost and the schedule of the spaceflight project, it is needed to know the value of the schedule-cost correlation coefficient. This paper deduces the schedule distribution, considering the effect of the cost, and proposes the estimation formula of the correlation coefficient between the in（schedule） and the cost. On the basis of the fact and Taylor expansion, the relation expression between the schedule-cost correlation coefficient and the in-schedule-cost correlation coefficient is put forward. By analyzing the value features of the estimation formula of the in-schedule-cost correlation coefficient, the general rules are proposed to ascertain the value of the schedule-cost correlation coefficient. An example is given to demonstrate how to approximately amend the schedule-cost correlation coefficient based on the historical statistics, which reveals the traditional assigned value is inaccurate. The universality of this estimation method is analyzed.
文摘On September 21,1992, the feasibility report on implementing China's Manned Spaceflight Project was approved and a three-step development strategy was also determined. From then on, China's Manned Spaceflight Project has developed rapidly.
文摘To evaluate the cost risk and the schedule risk of the spaceflight project,the schedule-cost(S-C) correlation coefficient is directly appointed according to the experts' experience usually.This paper deduces SDMCU(the schedule distribution model considering the effect of the cost uncertainty),and then proposes the approximate formula to estimate the ln(S)-C correlation coefficient based on the models of SDMCU and CDMSU(the cost distribution model considering the effect of the schedule uncertainty).Furthermore,an approximate relationship expression of the S-C and the ln(S)-C correlation coefficients is put forward according to general facts and the Taylor expansion,and advanced by means of mass numerical validation is the general rule of obtaining the estimation value of the schedule-cost correlation coefficient based on the historical data.
