Editorial: choosing new targets for rheumatoid arthritis therapeutics: too interesting to fail?

No abstract available

Analysis of Meteorological Data Obtained During Flight in a Supercooled Stratiform Cloud of High Liquid-Water Content

Flight icing-rate data obtained in a dense and. abnormally deep supercooled stratiform cloud system indicated the existence of liquid-water contents generally exceeding values in amount and extent previously reported over the midwestern sections of the United States. Additional information obtained during descent through a part of the cloud system indicated liquid-water contents that significantly exceeded theoretical values, especially near the middle of the cloud layer.. The growth of cloud droplets to sizes that resulted in sedimentation from the upper portions of the cloud is considered to be a possible cause of the high water contents near the center of the cloud layer. Flight measurements of the vertical temperature distribution in the cloud layer indicated a rate of change of temperature with altitude exceeding that of the moist adiabatic lapse rate. This excessive rate of change is considered to have contributed to the severity of the condition

An Electric Thrust Meter Suitable for Flight Investigation of Propellers

A lightweight instrument that utilizes resistance-wire electric strain gases to measure propeller-shaft thrust has been developed. A wind-tunnel investigation on a propeller installed, on a single-engine pursuit airplane showed that the instrument gave a reliable indication of propeller-shaft thrust to an accuracy of +/-2 percent within its calibrated range. No attempt was made to determine the relation of indicated shaft thrust to net propeller thrust

Are bang-bang minimum-time control policies evolutionarily inevitable?

The extent to which minimum-time control policies are necessarily bang-bang is investigated. It is shown that this very important issue can be conveniently examined by means of genetic algorithms. These general results are illustrated by the genetic design of a minimum-time controller for a second-order plant. It transpires that the control policies generated by a two-level hierarchy of genetic algorithms evolve towards a bang-bang form as the performance of the associated controller evolves towards time-optimality.published_or_final_versio