Abstract: An urgent need exists for a technique of rapid and economical measurement of vertical profiles of atmospheric particulate concentration. It is shown in this paper that the lidar, or optical radar, is capable of meeting ...

Abstract: After a theoretical discussion of the basic physical principles involved in the dew-point method of hygrometry, which serves to establish the inherent advantages of the technique, the paper describes the operating principles ...

Abstract: Following a brief review of the assumptions involved in the usual (Laplacian) expression for the speed of sound waves, an instrument, the sonic thermometer, is described which utilizes this relationship to measure the air ...

Abstract: The electronic dew-point hygrometer described by Barrett and Herndon in 1951 has been improved in three distinct areas: the servo-amplifier system, the optical system in the sensing head, and the operating-adjustment system. ...

Abstract: No Abstract Available