Abstract: An apparatus which dries compressed air by cooling it substantially to around its dew point. The apparatus includes at least a first heat exchanger, for the direct cooling of the compressed air, selectively associated with a refrigeration unit by a first refrigeration circuit. The first heat exchanger is immersed in a chamber containing a cooling liquid suitable to act as a thermal mass to accumulate the excess thermal energy generated by the refrigeration unit with respect to the energy needed to take the compressed air to dew point temperature. The apparatus also includes a second heat exchanger also immersed in the cooling liquid and suitable to intervene mainly during a momentary de-activation of the refrigeration unit. The apparatus is intended to dry compressed air with a high thermal yield and to substantially correlate energy consumption to the quantity of compressed air actually required.

Abstract: A stereoplotter with carriages and two distinct lens systems for viewing a pair of overlapping aerial photographic transparencies positioned on the carriages to produce a three dimensional optical model visible at the binocular viewer of the stereoplotter. The carriages are independently adjustable in two directions, and respond to both manual and computer control. A floating mark, or reticle, is introduced into the plane of the photographic transparency by each lens system. The operator, by manipulating manual or other controls, moves the floating marks into an apparently fused, or overlapping relationship, and then moves the fused mark along the surface of the optical model to generate a moving trace in X, Y and Z coordinates.Panoramic aerial photographs have posed significant problems for known stereoplotters, for an overlapping pair of photographs, to be viewed without distortion, required different magnification for each lens system.

Abstract: A device for adjusting to a predetermined value the rate of flow of air introduced into an enclosed space having at least one inlet for introducing warm or cold air by means of a fan into the enclosed space includes structure for controlling the velocity of the air thus introduced into the enclosed space, structure for varying the velocity of rotation of the fan, at least one extractor for discharging the air from the enclosed space, and structure responsive to the pressure prevailing in the enclosed space for setting the extractor speed so that the removal of air from the enclosed space is adjusted automatically as a function of the predetermined volume of air introduced into the enclosed space.