Abstract: An aerobic digestion process for reducing the solids content of an aqueous biodegradable organic sludge includes the steps of (a) introducing the sewage sludge into a vessel, the initial concentration of the total volatile organic solid in the sludge being less than about 2.5% by weight based on the total sludge present in the vessel, (b) maintaining the total volatile solids concentration at less than about 2.5% by weight; and (c) maintaining the temperature of the sludge in the vessel within the range of from about 38.degree. to about 46.degree. C. By processing the sludge according to the foregoing steps, including temperature maintenance within the foregoing critical limits and maintaining the total volatile solids concentration below the critical limit of about 2.5% by weight, the solids concentration of a sludge, such as a waste-activated sewage sludge, can be significantly reduced in a time period on the order of about three days.

Abstract: Disclosed is an apparatus for dispensing hay from large cylindrical bales formed of layers of hay spirally wound around a central axis. The preferred embodiment is comprised of a U-shaped frame detachably mountable on a three-point hitch of a tractor. The frame supports two rotatable, cylindrical rollers so oriented that a bale is supportable thereon. Powered rotation of one or both of the rollers causes the bale to rotate about its axis and the outermost layer of hay to be unwound from the bale and discharged between the rollers.

Abstract: The invention concerns the binding of refractory powders into self-supporting `green` shapes which are fired to provide refractory objects. In accordance with the invention the binders are based on zirconium salts and include a separate gell time delaying agent to ensure satisfactory gelling and to achieve control and to allow complex shapes to be made.

Abstract: A portable, toilet ventilating, air-filtering device for boats, house trailers, motels and the like, in which the housing interior is divided into opposite pressure-equalizing plenums by transverse partitioning filter means, and in one of these plenums is mounted a rotatively and vertically adjustable intake duct with spatulate nozzle head that can serve as a carrying handle when nested retracted against the housing top. A suction-blower mounted in communication with the opposed plenum draws air from the toilet bowl and through filter panels for discharge through a bottom opening into a discharge duct recessed in the bottom exterior.

Abstract: An environmentally durable, aluminum honeycomb structure is obtained by surface treatment and application of a polymeric film forming substance to the aluminum foil used in manufacture of honeycomb core prior to application of the adhesive and expanding the stacked and bonded core whereby the cells of the honeycomb core structure are formed. By application of a polymeric film forming substance before bonding, all surfaces of the honeycomb core are protected from corrosion and other environmental degradations. The presence of a polymeric film forming substance on honeycomb core surfaces aids in the formation of strong core-to-face sheet bonds by improving the fillet configuration and thereby the strength obtained in face sheet-to-core bonding.

Abstract: A modulated light beam is projected from a transmitter aircraft toward a receiver aircraft and reflected back toward the receiver aircraft by a retroreflector mounted on the receiver aircraft. The reflected light beam is received by the transmitter aircraft and is focused onto the face of an image dissector tube. The location of the reflected light beam on the face of the tube defines the position of the receiver aircraft in azimuth and elevation with respect to the position of the transmitter aircraft. The range difference between the two aircraft is determined by phase comparing the transmitted light beam with the received light beam. When used for in-flight refueling, further retroreflectors are mounted on a refueling boom and a similar technique is used to determine the exact location of the boom and its associated refueling nozzle.

Abstract: Noise generated by the tips of the fan blades in a turbofan jet propulsion engine is suppressed by generating an annular fluid layer or wake in the inlet of the turbofan engine forwardly from the fan blades and spaced inwardly from the inner wall of the inlet and by lining the inner wall of the inlet with an acoustically absorbent layer of material. Sound waves generated by the fan blades are reflected outwardly by the fluid layer and are absorbed in the acoustic absorbent layer on the inner wall of the inlet. In order for the wake to reflect sound waves, either the local fluid velocity in the wake must be lower than the fluid velocity of the surrounding airstream traveling through the inlet or the acoustic speed in the wake must be greater than or equal to the acoustic speed in the surrounding airstream. It is preferred that both conditions be met.

Abstract: An aircraft having a middle passenger-carrying deck, a lower cargo deck, and a forward, upper third deck, including an operating crew compartment, a passenger-carrying section or stateroom, and a main galley compartment in the aft portion of the third deck. The galley compartment is interconnected with an auxiliary galley compartment on the middle deck by two cart lifts through which the modular food and beverage containing carts can be elevated to the upper deck galley compartment for storage and lowered to the middle deck for in-flight food and beverage service to passengers.

Abstract: A system for verifying the user of a card in an automatic banking system and the like, wherein when a card is used for the first time after issuance, the user of the card himself manipulates the machine to input a secret number he intends to use with the card so that strict secrecy of the secret number can be maintained. The balance of the use's account is utilized for checking the correctness of the secret number when the card is used after the first use thereof.

Abstract: A pilot guidance system that computes and displays pitch and speed steering commands is automatically operated during the post-takeoff climb (at specified times clocked from the start of the takeoff run), to present commands that assist the pilot in cutting (and later in restoring) thrust for a predetermined interval to reduce engine noise, and in guiding the aircraft in a safe, gentle climb over the proximate community. The specified times (unique for each model of aircraft, airport, runway and departure flight path), synchronize the thrust cutback interval with the boundaries of the community in line with chosen departure path.

Abstract: A method of enhancing Coanda flow attachment over a wing and flap surface of an upper surface blowing aircraft comprising the step of directing the jet exhaust flow or stream toward regions wherein the exhaust flow separates from the wing and flap surface so as to create an outward velocity component which prevents ambient air from flowing in and under the exhaust from the sides of the exhaust flow and causing such separation is disclosed. The method comprises the further step of creating vortices also having outward velocity components on the wing and flap surface. The outward velocity components of the vortices further increases the sidewise velocity component on the wing surface. In addition, the rotational velocity components of the vortices scrub the boundary layer air from the flap surface to further promote flow attachment.

Abstract: A photometric device for use in a single lens reflex camera comprising a photometric optical system and a light receiving element disposed behind a pentaprism is disclosed. The light receiving element is disposed at a position where the image of a subject, imaged on a focusing glass plate by the photographing lens, is refocused by the photometric lenses. The light receiving area of the light receiving element is sized so that only a portion of the light refocused by the photometric lenses is received to provide a photometric operation that gives priority to a portion of the subject image.

Abstract: The invention concerns the binding of refractory powders into self-supporting "green" shapes which are fired to provide refractory objects. In accordance with the invention the binders are based on zirconium salts and include a dispersion of calcined magnesia in a mixture of water and a polyhydric alcohol. The magnesia reacts with the zirconium salt to form zirconium oxide/hydroxide which gells hard. In order to control the speed of gelling a separate gell time delaying agent is also optionally included.

Abstract: A pin fastening device having a double tapered head, the angle of one taper being on the order of 80.degree., or sufficient to withstand severe longitudinal forces, and the angle of the other taper being on the order of 10.degree., so as to provide a substantial interference fit between the pin and the work members. This double tapered head may be effectively utilized with a wide variety of pin fastener attachment end styles. Furthermore, an attachment end of a pin fastener is disclosed which includes a novel configuration of annular rings, which rings have a thread angle of 60.degree., and relatively small radii of curvature at their trough and peak. By having such a set of annular rings, one portion of the pin may be longitudinally extended sufficiently to give the pin large shear force resistance, while sufficient total ring surface is retained to withstand large tension forces. A single pin may thus have both a high shear and tension resisting capacity.

Abstract: A system for continuously, automatically sensing the setting of operator controlled switches that denote: (1) the need for operator assistance [CALL]; and, (2) the operational status [STATUS] of a plurality of numerically controlled (N/C) machines is disclosed. The sensed CALL and STATUS information is transmitted, in a highly noise immune push-pull voltage manner, from the N/C machine locations (e.g., shop area) to a central processing unit (CPU) located in a control room. The CPU processes the received information and in accordance therewith transmits CALL control signals to one or more visual paging boards located in the shop area and to a status display board located in the control room. The status board displays, in real time, the STATUS information and CALL information, plus the elapsed time since a particular STATUS state started, or a particular CALL was made.

Abstract: Disclosed is an instrument useful for effecting aspiration and irrigation during ophthalmic surgery. The disclosed embodiment comprises two, telescopically disposed cannulae and a connector which couples the two cannuli and forms fluid-tight seals with each. Each cannula consists of a rigid, small-diameter tube and a Luer hub (or "mount") coaxial therewith. The tube of the inner cannula is telescopically disposed within the outer cannula, the diameters of the cannulae being such that a passage is defined therebetween. The connector is of one-piece, rigid construction and includes a generally cylindrical body having a first nipple extending axially from one of its ends and a second nipple extending radially from one side. The first nipple is frictionally engaged within and forms a fluid-tight seal with the hub of the outer cannula. A cavity extends from the end of the first nipple through the body of the connector and terminates at the end of the body remote from the nipple.

Abstract: The outputs of one or more interconnected, unbiased photovoltaic devices mounted to receive light generated by one or more modulated light sources are connected via a long cable to the input of a balanced low impedance differential input line preamplifier. When multiple photovoltaic devices are included, their outputs can be directly interconnected and the thusly combined output will provide information about the intensity of light impinging on their photo conductive surfaces. The balanced low impedance differential input line preamplifier comprises a differential amplifier and a pair of common base input stages, one connected to each input of the differential amplifier. In a DC decoupling embodiment, capacitors are used to couple the common base input stages to the differential amplifier. The output of the balanced low impedance differential input line preamplifier is connected to a detector that provides an output indicative of the state of the output of the photovoltaic devices.

Abstract: An air stair-door combination for an aircraft is described in which interference between the door and the stairway in opening and closing thereof is eliminated by delayed motion of the stairway until the door is moved through a significant portion of its travel. The stair being interconnected to the door counterbalances a portion of the weight of the door, thus decreasing power requirements for opening and closing the stairway and door. A folding handrail structure adapted to nestle into the folded stairway is described. The door and stair actuator operates on a pivot point located on the door such that initial opening movement of the door causes stair operating rods to first travel downwardly past an overcenter point, then upwardly through further movement of the pivot point. The stair segments are projected outwardly by stair actuator linkage means driven by the operating rods.

Abstract: Welding apparatus for making metal honeycomb core panels by welding together preformed corrugated metal strips is disclosed. The assembled portion of the core panel is positioned by vertical finger electrodes on a horizontal base with the core panel workpiece end located along the line of a welding station extending across the base. The finger electrodes are arranged in two rows extending parallel to the welding station line, one row being insertable into the honeycomb core from above and the other being insertable into the core from below, each row also being movable from a first workpiece engaging position to a second welding position with one edge thereof along a welding station line. Welding heads, each including a welding element, are movable to and from the welding station. A corrugated metal strip is detachably held onto and carried to the welding station by the welding heads.

Abstract: As a mutation of Pacific Gold, a new peach tree variety is disclosed which is characterized by its dwarf nature and a predominance of vigorous, robust spurs, very short laterals with short internodes and prominent axillary buds.