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In the summer of 1999, we had used the bottom two layers of 3T to provide autonomous control for a single subsystem--a second-generation biological water processor--during a 450-day, 24-hour-a-day, 7-day-a week test. 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).BuildupUsing 3T allowed us to develop the control for the bowlingballdrillpress IWRS in a modular fashion in two ways. First, moving from bottom to top (figure 4), each layer bowlingballdrillpress has its own data structures, timing constraints, and development tools that allow for parallel development of the software. Thus, we were able to develop skills sets based on the evolving hardware specifications and simultaneously develop the sequencer procedures. Early on, as the water research team developed the design for each subsystem, one part of the 3T team wrote the sequencer procedures bowlingballdrillpress for each subsystem in the RAPS language (which, in turn, is written in Lisp) (1) using virtual skills, that is, Lisp skills connected to a Lisp simulation of the expected hardware. A virtual simulation of, say, the reverse-osmosis subsystem could then be shown on a laptop to the WRS engineers and the control design refined in an iterative process even before the actual hardware was available. The primary result of this process was a set of skill specifications for each subsystem (figure 5). In a report, bowlingballdrillpress the panel said it is necessary to leave the gates open for ''''at least a few years'''' and to monitor any subsequent changes to the area''s ecosystem.Since Yatsu earlier pledged to live up to the panel''s recommendations, the gates are likely to remain open for a long period once they are opened.The panel made its recommendations after examining the findings of a ministry research team that gathered and analyzed samples of water and sludge from the area.The 12-day probe, which began March 15, covered water quality, organic materials and nutrient salts such as nitrogen and phosphorus in the sludge and soil inside and outside the 7,050-meter-long dike for the 1,710-hectare reservoir. The following Wednesday nobody showed bowlingballdrillpress up. A week later, the table disappeared bowlingballdrillpress into the basement, where it soon became moldy from a water leak. It took a month before we could look at each other in the eye and the notion became, unanimously and without deliberation, a topic of taboo.But the idea of a round table, where no seat is privileged, and all eyes look through the same pocket of air, has continued its hold on me. After years of carrying the notion with me through travels and co-ops, I now find myself literally carried by the idea. A community around a table is--in many ways--the real thing, not just the launching pad.
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