Space Station Freedom ECLSS: A step toward autonomous regenerative life support systems

The Environmental Control and Life Support System (ECLSS) is a Freedom Station distributed system with inherent applicability to extensive automation primarily due to its comparatively long control system latencies. These allow longer contemplation times in which to form a more intelligent control strategy and to prevent and diagnose faults. The regenerative nature of the Space Station Freedom ECLSS will contribute closed loop complexities never before encountered in life support systems. A study to determine ECLSS automation approaches has been completed. The ECLSS baseline software and system processes could be augmented with more advanced fault management and regenerative control systems for a more autonomous evolutionary system, as well as serving as a firm foundation for future regenerative life support systems. Emerging advanced software technology and tools can be successfully applied to fault management, but a fully automated life support system will require research and development of regenerative control systems and models. The baseline Environmental Control and Life Support System utilizes ground tests in development of batch chemical and microbial control processes. Long duration regenerative life support systems will require more active chemical and microbial feedback control systems which, in turn, will require advancements in regenerative life support models and tools. These models can be verified using ground and on orbit life support test and operational data, and used in the engineering analysis of proposed intelligent instrumentation feedback and flexible process control technologies for future autonomous regenerative life support systems, including the evolutionary Space Station Freedom ECLSS

The environmental control and life support system advanced automation project. Phase 1: Application evaluation

The Environmental Control and Life Support System (ECLSS) is a Freedom Station distributed system with inherent applicability to advanced automation primarily due to the comparatively large reaction times of its subsystem processes. This allows longer contemplation times in which to form a more intelligent control strategy and to detect or prevent faults. The objective of the ECLSS Advanced Automation Project is to reduce the flight and ground manpower needed to support the initial and evolutionary ECLS system. The approach is to search out and make apparent those processes in the baseline system which are in need of more automatic control and fault detection strategies, to influence the ECLSS design by suggesting software hooks and hardware scars which will allow easy adaptation to advanced algorithms, and to develop complex software prototypes which fit into the ECLSS software architecture and will be shown in an ECLSS hardware testbed to increase the autonomy of the system. Covered here are the preliminary investigation and evaluation process, aimed at searching the ECLSS for candidate functions for automation and providing a software hooks and hardware scars analysis. This analysis shows changes needed in the baselined system for easy accommodation of knowledge-based or other complex implementations which, when integrated in flight or ground sustaining engineering architectures, will produce a more autonomous and fault tolerant Environmental Control and Life Support System

Experimentalist Equal Protection

Elsewhere Garrett and Liebman have recounted that though James Madison is considered the Father of the Constitution, his progeny disappointed him because it was defenseless against self-government\u27s mortal disease -the oppression of minorities by local majorities-because the Framers rejected the radical structural approach to equal protection that Madison proposed. Nor did the framers of the Fourteenth Amendment\u27s Equal Protection Clause and federal courts enforcing it adopt a solution Madison would have considered effectual. This Article explores recent subconstitutional innovations in governance and public administration that may finally bring the nation within reach of the constitutional polity Madison envisioned To explain how Madisonian governance mechanisms can solve the problem of equal protection, the authors turn to the thinking of another homegrown practical philosopher who was ahead of his time, John Dewey. Dewey sets out what he calls an experimentalist problem-solving method for curing the equal protection ills Madison diagnosed In two core civil rights contexts, public school reform and workplace discrimination, solutions both Madisonian and Deweyan already point the way to an experimentalist equal protection regime that remains well within our reach. Such experimentalism may not only open our rigid, tepidly enforced equal protection doctrine to an evolving, problem-solving approach, but in the process transform democratic institutions and community

A new, large-scale map of interstellar reddening derived from HI emission

We present a new map of interstellar reddening, covering the 39\% of the sky with low {\rm HI} column densities ($N_{\rm HI} < 4\times10^{20}\,\rm cm^{-2}$ or $E(B-V)\approx 45\rm\, mmag$) at $16\overset{'}{.}1$ resolution, based on all-sky observations of Galactic HI emission by the HI4PI Survey. In this low column density regime, we derive a characteristic value of $N_{\rm HI}/E(B-V) = 8.8\times10^{21}\, \rm\, cm^{2}\, mag^{-1}$ for gas with $|v_{\rm LSR}| < 90\,\rm km\, s^{-1}$ and find no significant reddening associated with gas at higher velocities. We compare our HI-based reddening map with the Schlegel, Finkbeiner, and Davis (1998, SFD) reddening map and find them consistent to within a scatter of $\simeq 5\,\rm mmag$. Further, the differences between our map and the SFD map are in excellent agreement with the low resolution ($4\overset{\circ}{.}5$) corrections to the SFD map derived by Peek and Graves (2010) based on observed reddening toward passive galaxies. We therefore argue that our HI-based map provides the most accurate interstellar reddening estimates in the low column density regime to date. Our reddening map is made publicly available (http://dx.doi.org/10.7910/DVN/AFJNWJ).Comment: Re-submitted to ApJ. The reddening map is available at http://dx.doi.org/10.7910/DVN/AFJNW