Abstract: Highwasy crossing protection equipment which operates warning lights or crossing gates is controlled from the train locomotive which enters into an interchange of messages via a radio link with the controller at the crossing. Communications between the train and the crossing controller is initiated when the locomotive passes a trackside beacon transponder located beyond a safe braking distance from the crossing. The crossing controller transmits a message addressed to the train acknowledging the receipt of the train signal. The interchange of messages can be repeated a plurality of times; each time the minimum time being updated so that traffic flow across the crossing is handled efficiently with minimum interference.

Abstract: A doser-dispenser has a single doser unit which is associated with at least two dispenser units. The outlet of the dosing chamber of the doser unit is connected in parallel to each of the dispensing chambers of at least two dispenser units. The active volume of the dosing chamber holds at least two whole doses of product to be dispensed through the two distinct dispenser units. A synchronization device which coordinates the movements of the doser-piston and of the intake flap, with a result that, during delivery of a first dose of product out an dosing chamber, only the ejection valve of the first dispenser unit is open, that, during delivery of the second dose of product, only the ejection valve of the second dispenser unit is open, and so on.

Abstract: A steady bearing for the free end of a mixer shaft, which may be made from composite (fiber reinforced plastic) materials in substantial part, has a generally bell-shaped body with a neck in which the free end of the shaft or a shaft extension is disposed. A bearing assembly is removably disposed in the neck. The bearing has a bushing which is keyed to an inner sleeve around the shaft and to an outer sleeve by keyways which are open at one end so that the bushing and outer sleeve can be axially displaced for initial installation of the steady bearing and also when the bushing thereof requires replacement. When the shaft is too large to fit inside of the steady bearing. A reduced diameter shaft extension is provided to fit the steady bearing.

Abstract: Projectors and cameras disposed about an object under test obtain digital moire information of overlapping aspects (views) of the object. The system is calibrated using a calibration pattern of straight lines on a flat reference surface and a projected pattern of lines which are perpendicular to the lines of the calibration pattern and contain marker fringes between predetermined lines. Each aspect is calibrated individually by stepping the calibration pattern along the axis of each camera so as to obtain a plurality of tables which relate phase information to distance in each of a plurality of planes spaced successively closer to the camera. The calibration tables define a calibrated volume in space between the cameras and projectors. When the object under test is located in this volume, the video signals from the camera are converted into digital moire information.

Abstract: A rotary, continuous pyrolytic conversion system converts solid hydrocarbon containing feedstocks into gases, liquid hydrocarbons and char. A converter drum is contained within an outer drum which is in substantially air-tight relationship with an injector for introducing the feedstock in the form of bales and with a discharge chute for the solid products of pyrolysis. A casing around the outer stationary drum defines an oven chamber which is heated by combustion products. A rod extends into the injection end of the converter drum for supporting scrapers against the inner periphery of the converter drum. A crusher bar is carried in the drum at the discharge end thereof and crushes the solid products. A second pyrolysis reactor may receive the solid pyrolysis products and be operative at higher temperature than the first converter to destroy chlorinated hydrocarbons.

Abstract: A lens in a waveguide of an integrated optical circuit is achromatized (corrected for chromatic dispersion which varies the focal length of the lens with wavelength) by forming the lens as a hybrid mode-index/diffractive doublet. The chromatic dispersion of the diffractive element cancels the dispersion of the refractive element (the mode-index lens) such that the derivative of the focal length goes to zero at the design wavelength, and significantly reduces chromatic dispersion over a substantial wavelength range. For example, a 10 mm focal length, F/5 hybrid mode-index/diffractive lens may be provided with a useable wavelength range of approximately 80 mm for typical waveguide materials.

Abstract: A method of injection molding a thermoplastic material around a two-piece insert having a rotational axis through which a bore passes is disclosed. The insert is formed from two pieces which are axially spaced to define an annular gate through which the injected thermoplastic material passes radially outward. This technique is particularly useful for forming mixing impellers, because it orients fibers contained within the thermoplastic material in a radially outward direction within the impeller's blades to provide increased strength. The insert also allows improved performance for injection molding parts by reducing their cross-sectional thickness to optimal values. The insert also allows machining the bore without harming the injected plastic material.

Abstract: An electro-optic device, which processes by modulating, switching or gating, a light beam in response to an electrical signal utilizes an electro-optic crystal through which the beam to be processed passes. An electric field is generated by pulses which modulate the crystal's index of refraction and also causes piezoelectric ringing in the crystal. Acoustic energy absorbing material is coupled to the crystal for absorbing the piezoelectrically generated acoustic waves propagating perpendicularly to the applied electric field direction which has been found to be the dominant acoustic mode affecting the birefringence of the crystal and causing the ringing. The field is applied in short pulses (of the order of 10 nsec or less) thereby reducing lower frequencies in the acoustic energy spectrum thereby facilitating the absorption of the ringing energy.

Abstract: A standby power supply system (SPS) is connected to supply power to a load by way of a transfer switch, to replace power from the AC lines, when the AC line fails to provide sufficient voltage to operate the load (e.g., 85% of nominal RMS voltage usually 120 VAC-RMS). The SPS has an inverter which switches voltage from a battery to generate AC power when the line fails. The inverter is controlled by varying the width of switching pulses in order to regulate the AC output voltage and compensate for reductions in battery voltage as the battery discharges. The AC output voltage is also synchronized with the line voltage when the line voltage returns (increases to greater than 85% of nominal value) so that on switch over back to the AC line, the AC waveform applied to the load does not change substantially before and after switch over.

Abstract: Networks which remove the jamming signal from the television signal supplied to subscribers for a premium T.V. channel in a cable (CATV) or other subscription television system utilizes surface accoustic wave (SAW) devices arranged to provide a broadband all pass response across the entire band covered by all of the transmitted television channels except for a notch at the frequency of the jamming signal. The narrow band response of the filter in the premium channel is such that the notch presents insertion loss at the jamming signal frequency and over a frequency range to accommodate shifts in the frequency response of the SAW devices with respect to the frequency of jamming signal, which insertion loss is about 100 times the insertion loss at the picture carrier frequency of the television signal, even though the picture carrier and the jamming signal frequency may be within about 200 KHz apart from each other.

Abstract: A vending machine has a carousel containing several rotatable trays stacked one above another. The trays carry and present for vending selected items, such as food and merchandise. The carousel is contained in a housing or canister and is part of an integrated assembly with a coin container. The carousel is filled at a central depot rather than at the site where the machine is installed for use by customers. The customer locations have the cabinet of the machine. Fixed in the cabinet is a drive mechanism for the carousel and locating and guide members which enable integrated assemblies to be removed from the cabinet and fresh assemblies, with the carousel trays loaded at the central depot, to be installed in place of the removed assemblies. The coin box when empty is equipped with a mechanism which is set to enable coins to drop into the container and is automatically reset so as to close the opening when the assembly is removed from the cabinet.

Abstract: Gradient-index glass is produced in a sol-gel process by utilizing water or a mixture of water and alcohol. This technique is particularly suitable for production of glass bodies with a ternary system of metal alkoxides, including silicon alkoxide, an index modifying metal alkoxide, such as alkoxides of titanium and zirconium, and an additional metal alkoxide, such as an alkoxide of aluminum, boron, or germanium.

Abstract: A weatherstrip having a backing member and a pair of rows of pile of different height above said backing strip. A flexible fin is disposed between said rows and has a height equal or slightly greater than the height of the higher row. When sash members, such as those of a horizontal sliding window move into closing relationship, the fin bends causing bending of the higher row forming a seal between the sash members while the row of lower height is not substantially compressed and provides a springlike force opposing the mechanism which holds the sliding sash.

Abstract: Laser beam apodizers using cholesteric liquid crystals provides soft edge profile by use of two separate cholesteric liquid crystal mixtures with different selective reflection bands which in an overlap region have a gradient index where reflectivity changes as a function of position. The apodizers can be configured as a one-dimensional beam apodINTRODUCTIONThe U.S. government has rights in the invention under Contract No. DE-FC03-85DP40200 between the University of Rochester and the Department of Energy.

Abstract: Composite optical devices using polymer liquid crystal materials both as optical and adhesive elements. The devices are made by assembling a heated polymer liquid crystal compound, while in a low viscosity form between optically transparent substrates. The molecules of the polymer are oriented, while in the liquid crystalline state and while above the glass transition temperature (T.sub.g) of the polymer, to provide the desired optical effects, such as polarization, and selective reflection. The liquid crystal polymer cements the substrates together to form an assembly providing the composite optical device.

Abstract: A system for time-resolving ultra-short electrical waveforms of up to a few hundred gigahertz bandwidth is presented. The system utilizes a fast electro-optic modulator capable of subpicosecond responsivity. A CW (continuous wave) laser is used to probe the change in birefringence resulting in the modulator due to an induced electric field. The rapid change in the transmitted optical signal due to an equally rapid changing electric field (picosecond pulse) is then detected and temporally dispersed using a picosecond resolution streak camera. The modulator operates in a region close to minimum transmission where the average optical power is below the damage threshold for the photocathode of the streak camera and where small electrical signals can significantly modulate the transmitted beam. The system can be used in either sampling mode where the modulation and subsequent detection are repeated and the data accumulated at repetition rates as high as 100 MHz or in single shot mode.

Abstract: A switch machine operates a track switch under radio control via a switch controller. The switch controller may be given an identifying address unique to it which distinguishes the switch machine from other switch machines in the railway territory. In addressing or programming the switch machine, a portable terminal is used. The controller is enabled by a manually actuable switch to accept identifying addresses which is stored in electrically erasable programmable read-only memory (EEPROM). Whenever a message is received over the radio link, the identifying address is read out of memory. In order that the identifying address is vital (fail-safe) and to guard against any errors which change the identifying address and which can cause the controller to effectuate operation of the track switch in front of an oncoming train or when the train is over the switch, the address is stored in the EEPROM by encoding the identfying address into unique multi-bit check words.