Characterizing a Portable Subset of Behavioral VHDL-93

Goossens defined a structural operational semantics for a subset of VHDL-87 and proved that the parallelism present in VHDL is benign. We extend this work to include VHDL-93 features such as shared variables and postponed processes that change the underlying semantic model. In the presence of shared variables, nondeterministic execution of VHDL-93 processes destroys the unique meaning property. We identify and characterize a class of portable VHDL-93 descriptions for which unique meaning property can be salvaged. Our specification can serve as a correctness criteria for a VHDL-93 simulator

Increasing CO2 from subambient to superambient concentrations alters species composition and increases above-ground biomass in a C3/C4 grassland

The glacial-to-present increase in atmospheric CO2 concentration is likely to have stimulated plant production, but experimental tests in natural ecosystems are lacking

Programmed Monitoring and Digital System Simulation

http://trove.nla.gov.au/work/1591416