Abstract: In order to provide an optical reflectivity test plate for calibrating and proving a radiometer, which test plate exhibits a near-Lambertian surface, a ceramic coating is bonded to a surface of a rigid substrate, such as a steel plate, and the ceramic coating is thereafter sandblasted with a fine abrasive (preferably 60 grit or finer). If ordinary silica or other relatively soft abrasive is employed in the sandblasting step, it must not have have been previously used. Test procedures for comparing the resultant test plates to a standard BaSO.sub.4 test plate in both the laboratory and outdoors are given.

Abstract: Apparatus is provided to sense and measure solar-induced luminescence, as well as reflectance, within the field of view of a target window for receiving a composite ray of light from the target. A first filter within the path of the composite ray of light transmits a first narrowband component thereof, including a predetermined Fraunhofer Line frequency, to a first sensor. A second narrowband component thereof, proximate the Fraunhofer Line frequency, is directed to a second sensor such that ratios of the electromagnetic energy impinging, respectively, on the first and second sensors may be determined. A removable filter tray carrying the narrowband filters and fine tuning means is employed to facilitate the selection of the predetermined Fraunhofer Line frequency.

Abstract: A radiometer for detecting and measuring components of luminescence and reflected light contained in a light beam from a target which included means for sensing the temperature of an optical filter in the radiometer and for adjusting the angular position of the mount which carries the filter in response to the sensed temperature to thereby retune the filter to its center frequency when changes in temperature occur. Longitudinal movement of an adjustment rod changes the angular position of the mount. A micrometer means manually moves the rod in one embodiment while a motor moves the rod in a second embodiment. The rod carries a means for sensing the longitudinal position of the rod (hence the rotational position of the mount) and generates a signal representative thereof. A means on the mount senses the temperature of the filter and generates a signal representative thereof.

Abstract: The present invention provides a radiometer for simultaneously detecting luminescence and reflectance about a particular Fraunhofer line from a material (i.e. target) which includes an interchangeable optical filter assembly of lightweight construction for each Fraunhofer line of interest which substantially alleviates the adverse polarization effects normally experienced in radiometers of this type and which further provides an improved balance between the two light beams being sensed by the radiometer. The optical filter assembly includes a single beamsplitter which reflects the majority of the light from the target with little adverse polarization effects to a narrow band filter which passes only the light existing at the particular Fraunhofer line (i.e. "c" component of luminescence).

Abstract: In order to provide an calibration plate having both known reflectance and known luminescence characteristics for calibrating and proving a radiometer, which calibration plate exhibits a near-Lambertian surface reflectance, a ceramic or glass coating containing a rare earth photoluminescent material is bonded to a surface of a rigid substrate, such as a steel plate, and the ceramic coating is thereafter sandblasted with a fine abrasive in good condition.

Abstract: In order to achieve fine control of the velocity of an aircraft flying a predetermined flight path at a predetermined nominal speed in the presence of such perturbations as wind gusts, a low inertia, fast acting device is extended or deployed into the aircraft dragstream and is rapidly position-modulated in response to sensed acceleration/deceleration to instantaneously slightly alter the total system drag to an amount which causes the aircraft to maintain the predetermined velocity. Among the exemplary alternative low inertia devices disclosed are: fuselage and wing mounted flaps which are rapidly more or less extended, a trailing cable which is rapidly reeled in or out, and a trailing inflatable member whose degree of inflation is rapidly changed, all in response to sensed acceleration/deceleration from an on-board system.

Abstract: In order to achieve fine control of the velocity of an aircraft flying a predetermined flight path at a predetermined nominal speed in the presence of such perturbations as wind gusts, a low inertia, fast acting device is extended or deployed into the aircraft dragstream and is rapidly position-modulated in response to sensed acceleration/deceleration to instanteneously slightly alter the total system drag to an amount which causes the aircraft to maintain the predetermined velocity. Among the exemplary alternative low inertia devices disclosed are: fuselage and wing mounted flaps which are rapidly more or less extended, a trailing cable which is rapidly reeled in or out, and a trailing inflatable member whose degree of inflation is rapidly changed, all in response to sensed acceleration/deceleration from an on-board system.

Abstract: In gas volume measurement apparatus employing an orifice plate, wear on the edges of the orifice affect its area and hence the accuracy of the volumetric measurement. In order to correct for the effects of such wear, a probe element is inserted into the same flow path as the orifice. The probe element itself wears to change a fundamental characteristic, typically resistance, which can be related to the orifice wear and thus provide a correction factor to the volumetric calculations.

Abstract: In order to determine the pulse repetition rate of a fluidic oscillator through which a test gas, whose density is to be determined, is flowing, the pressure pulses appearing at one outlet port of the oscillator is sensed with a pressure transducer. The pulses are integrated for a sample period such that, upon transfer or display, the accumulated count directly represents the average pulse repetition frequency during the sample. Means are provided, in a surge tank, for controlling the temperature and pressure of the test gas, and temperature and pressure transducers in communication with the sample fluid in the surge tank are each coupled to voltage-to-frequency converters which drive counters in order that the temperature and pressure of the test gas may also be displayed. An interface to a thermal printer allows the preservation of written records of prf, temperature, and pressure readings. An interface to a digital tape recorder permits magnetic recording of the data for subsequent processing.

Abstract: In order to determine the density of a test gas, the test gas is employed as the working fluid through an astable fluidic oscillator. Air, at the same temperature and pressure, is passed through the same or a like fluidic oscillator to obtain a second pulse repetition frequency reading. The density of the test gas is the ratio of the two pulse repetition frequencies. Preferably, for a given fluidic oscillator, graphs and/or tables are prepared giving the pulse repetition frequency of air at different temperatures and pressures in order that subsequent measurement of the pulse repetition frequency using a test gas will permit direct determination of the specific gravity of the test gas from a graph or table.

Abstract: In order to determine the constituent gases of a gas mixture, the test gas is employed as the working fluid for an astable fluidic oscillator in a series of runs taken at different temperatures. The pulse repetition frequencies observed are related to similar pulse repetition frequencies observed when air is employed as the working fluid at corresponding temperatures and pressures. By this means, a plurality of equations can be written and solved for the unknown percentages. The characteristics of a given astable multivibrator can readily be predetermined and recorded on a graph in a table to facilitate preparation of equations which can be solved by ordinary simultaneous equation techniques.

Abstract: A cutting-chipping system comprising an interconnected triaxial array of rotating drums each mounted for independent rotation. Each drum includes a plurality of spaced, outwardly extending teeth to sequentially cut, chip and break particulate mass such as coal or ice engaged by the system. The drums are oriented with no axis of drum rotation parallel to another and in a configuration wherein the direction of cutter travel from one drum is oblique to that of a second drum. In this manner, particulate matter engaged by the system is initially cut and chipped by a first drum to form a series of protuberances and/or weakened sections which, when struck at an oblique angle by a second drum, will chip and break away. The teeth may be comprised of picks, chisels or combinations thereof constructed and adapted for bidirectional rotation. The system may be adapted for applications upon land vehicles, water crafts, floating platforms, and the like.

Abstract: A method of and apparatus for the installation and retrieval of instrumentation hardware supported through a hole in a section of ice is provided wherein an expansion member such as an inflatable bladder is utilized for displacing water normally subject to freezing within the hole. The inflatable bladder comprises an elongated expandable sleeve of sufficient length to substantially extend the ultimate depth of the hole in the ice for engaging and bearing against the sidewalls thereof. A portion of the hardware adapted for the surface support thereof may be disposed within the bladder as well as therebeneath and may be retrieved at a date subsequent to installation by deflating the bladder without the problem of said hardware being frozen in or beneath the ice.

Abstract: A portable structure which consists of a plurality of I beams placed side by side and hinged together in a parallelogram fashion such that adjacent I beams may be folded together.

Abstract: A work platform for oil drilling, oil production, or other purposes is constructed in arctic waters by locating a natural ice island of suitable area and thickness, and moving it to the desired platform location. The ice island is anchored to the sea floor by installing at least one, but preferably a number of, generally cylindrical sheaths beneath it which extend from the island to the sea floor below. The sheaths are filled with water, and a thermosiphon is installed interiorly of the sheath. As the thermosiphon extracts heat from the water within the sheath, the water is converted to ice, and eventually the entire body of water within the sheath is frozen, thereby forming a column of ice which anchors the island to the sea floor in the desired location.

Abstract: A centrifugal pump of rotating case and fixed arm configuration having a plurality of orifices on the stationary arm to accomodate multi-phase flow whereby the mixed phase charge is separated and discharged at high pressure due to centrifugal force created by the case rotation.