“You cried and cried and cried, and I wanted so much to comfort you, and I knew that I just mustn’t pick you up and hold you. That’s what they told me, so I believed them.” That was a mother in my own family, apologizing decades later to her adult daughter. The mother still suffered because she had not dared to comfort her baby. In Love at Goon Park, Deborah Blum tells the extraordinary story o...

An Euler shocktting marching code yields good agreement with semiempirically determined plume shapes, although the agreement decreases somewhat with increasing nozzle angle and the attendant increase in the nonisentropic nature of the ow. Some calculations for a low-boom con guration with a sample engine indicated that, for ight at altitudes above 60 000 ft, the plume e ect is dominant. This ne...

The interaction of a diffusing outgas flow from a sphere nose opposing a hypersonic free stream is studied numerically by the direct simulation MonteCarlo technique under the transitional rarefied-gas-flow regime conditions at Knudsen numbers from 0.016 to 1.5 and blowing factors from 0.15 to 1.5. Strong influences of the blowing factor (the ratio of outgas mass flux to upstream mass flux) and ...

Synergy of various kinds has played a significant creative role in evolution; it has been a prodigious source of evolutionary novelty. Elsewhere it has been proposed that the functional (selective) advantages associated with various forms of synergistic phenomena have been an important cause of the "progressive" evolution of complex systems over time. Underlying the many specific steps in the c...