Mean future irrigation water requirements (IWRs) and anomalies (Aa) * IWR (cm) IWR (cm) IWR (cm) Crop Baseline (2025) (2055) (2085) Bean 1.85 1.01 0.31 0.31 Corn 1.90 1.49 0.44 0.54 Soybean 7.59 5.65 4.25 2.64 Wheat 0.49 0.04 0.45 0.11 Aa (cm) Aa (cm) Aa(cm) Crop Baseline (2025) (2055) (2085) Bean 1.85 -0.84 (-45) -1.54 (-83) -1.54 (-83) Corn 1.90 -0.41 (-22) -1.46 (-77) -1.36 (-72) Soybean 7.59 -1.94 (-26) -3.34 (-44) -4.95 (-65) Wheat 0.49 -0.44 (-91) -0.03 (-7) -0.38 (-78) * Values in parentheses represent percentage
Figure 2 shows the variability of IWR for all periods analyzed, which are 30 years each.
Wheat showed a higher IWR peak in 2055 (3.93 cm) compared to the current period (3.61 cm).
Although commonly phrased as a sustainable withdrawal rate, the research commonly applies the technique by determining an initial withdrawal rate (IWR), and assumes that the dollar amount produced by the IWR will be adjusted annually for inflation.
For example, if the safe IWR is 5%, and the retiree has an account balance of $1,000,000, then the retiree is assumed to spend $50,000 in the first year ($1,000,000 x 5%), and in subsequent years is assumed to increase the $50,000 amount by inflation.
Thus, in practical use the IWR is often increased in the future by more than just inflation adjustments, but not until the results of the portfolio actually merit such an increase, as ill-timed increases could otherwise put a safe withdrawal rate into jeopardy.
The time frame was the winter of 1999, and this exchange was typical of many conversations that the Al controls team from the Automation, Robotics, and Simulation Division (AR&SD) at Johnson Space Center (JSC) would have with the advanced water-recovery personnel as the two groups prepared for a year-long test of a new Integrated Water-Recovery System (iWRS), slated to begin in January 2001.
This article is the story of our experiences developing and running the iWRS AI control system.
Then in January 2000, the Advanced Water Research Group received ALS funding for the year-long IWRS test, involving four advanced water-recovery subsystems (Bonasso 2001) (see Advanced Water Recovery System sidebar).
With the emergence of the Internet and interactive Web response (IWR
) technology, along with advancements in automated underwriting, predictive behavior for credit and prepayment models and interactive voice-recognition (IVR) telephone systems, effective mass customization of consumer-direct marketing and responsive customer service is possible.
Moreover, eClinical trial solutions like EDC, IWRS
, clinical trials management systems and sophisticated trial reporting tools have solved many of the language and project management difficulties associated with running trials all over the world.
Given the data entry requirements of a large, late-phase study, sponsors are increasingly selecting study sites based on their ability to utilize more advanced technology, such as IWRS
, to perform these functions.