Contract Over Target Baseline (OTB) Effect on Earned Value Management's Cost Performance Index (CPI)
Abstract : Cost growth is a problem in U.S. Department of Defense (DoD) acquisitions. A particular component of cost growth is a cost overrun or Over Target Baseline (OTB). In 2009, Trahan found that the Gompertz growth curve better predicted program Estimates at Completion (EAC) for OTB contracts. In 2010, Thickstun studied "the relationships between overruns and a variety of factors," but found OTB occurrences "random" and questioned the benefit of the OTB process (Thickstun, 2010). In this research, we study OTB's ability to effect improved program cost performance; we examine OTB's effect on the cumulative Cost Performance Index (CPI) slope after an OTB intervention. We find there is no statistically significant change in cumulative CPI slope after OTB. For the data studied, an OTB investment does not significantly improve management's ability to earn cost value as reflected in the cumulative CPI slope.
Using Earned Value Data to Forecast the Duration of Department of Defense Space Acquisition Programs
Traditional earned value management techniques to predict final costs of space acquisition programs are historically inaccurate. A 2015 study by the Air Force Cost Analysis Agency (Keaton 2015) sought to improve the accuracy of the cost estimate at completion for space system contracts through a linear relationship between budgeted cost for work performed and time. That study found schedule duration to be a cost driver, but assumed the underlying schedule duration estimate was accurate. This research expands upon the previous research through an improved duration estimation methodology. Next, we incorporate our duration methodology into various estimate at complete models to derive a more accurate estimate at complete for space acquisition programs. Our methods improve the accuracy by 6.5% over existing methods. The results offer an alternative approach to schedule duration estimates and earned value estimate at complete calculations that may be useful to cost analysts and program managers.
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.