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Electrochromic devices offer potential benefit as variable emissivity radiators for advanced extravehicular activity (EVA) suits. Supplementing (or even replacing) the water sublimator with radiators will result in reduced mass consumption for heat rejection, and radiators can be effective in environments where sublimation is not possible. The exotic properties of electrochromic devices (ECDs) may also lead to radiators that are capable of adapting, without mechanical actuation, to changing EVA operations and environments. Three concepts for the implementation of flexible electrochromic radiators are presented, along with a preliminary thermal analysis for each configuration.

This study investigated the possibility of detecting water deficit stress in plants by using optical signals collected from leaves. Two theoretical approaches have been investigated. In principle, chlorophyll fluorescence can be used to measure generally stressful situations in plants. Our review, however, found that simple ratios of coarsely time-resolved chlorophyll fluorescence, such as maximum fluorescence over fluorescence at steady state, appear to be incapable of adequately distinguishing water stress from other stress factors. A second principle being investigated involves correlation of light absorption within leaves to leaf-water-content using water absorbing and non-water absorbing wavelengths. Our investigation concentrated on defining and eliminating as many extraneous variables as possible.