Abstract: A method of detecting a concentration of contaminants in an air sample. The method includes the steps of combining a first portion of the air sample with a fuel to produce a sample/fuel mixture, igniting the sample/fuel mixture in a combustion chamber to produce a flame, and supplying a second portion of the air sample to the combustion chamber so that at least some of the contaminants contained in the second portion are ionized by the flame.

Abstract: A local area network having fault detection and recovery and a method for detecting and recovering from faults in a local area network are disclosed. The network has modules interconnected by a token bus implemented by a pair of redundant cable systems. All of the modules are agent modules and one of the modules also serves as a master module. Each agent module periodically transmits an agent heartbeat signal on each of its cables. Each module monitors all of the agent heartbeat signals from all of the other modules. When a fault is detected by a module, such as missed agent heartbeat signals from another module, the module applies agent rules to determine if and how the fault should be reported. The agent module reports the fault to the master module. The master module collects fault reports from the agent modules, applies a set of master rules to the agent fault reports, and generates a master failure report.

Abstract: The invention comprises a method of completely sorting an unsorted data table in a single pass through the data. The method uses a relatively large amount of computer memory, but sorts the data at great speed. Specifically, each unsorted data word is scaled to a size equal to or less than the number of address locations in a sort table. The scaled value created for each unsorted data word is converted to an address increment which is added to the initial address of the sort table. The unsorted data word is then stored into the sort table at the above calculated address that is related to the value of the data word. In this way, most words are placed in a sorted arrangement without comparison or iteration. The invention also comprises a method for resolving conflicts where a calculated address for an unsorted data word already contains a sorted data word. In this case both words are then sorted with respect to each other to create a data subclass and stored in an auxiliary storage table.

Abstract: A chromatography device for separating sample fluids from carrier fluids and analyzing the sample is configured so that it is a modular unit. This modularity enables repairs to be quickly effected on the unit and also greatly simplifies the task of accessing the components of the chromatography cartridge. The modular chromatography cartridge is comprised of separation columns for separating the sample fluid from the carrier fluid. The cartridge additionally includes detectors for detecting distinguishing characteristics of fluids exiting the column. Further, the cartridge preferably includes valve assemblies for directing the flow of the carrier fluid and sample fluid throughout the cartridge and restrictors for adjusting the flow rate of the fluids as they flow through the cartridge. All of the components of the cartridge are configured upon a manifold. The manifold has a means for attaching the cartridge to fluid sources and support structure. The manifold enables the system to exhibit its modularity.

Abstract: Application interface software provides communication between a network of computer nodes and user applications of a host processor. Interpreters or gateways are used between the host processor and the network of computer nodes. The application interface software employs a redundancy routine to ensure host access of computer node data through the gateways. The redundancy routine changes access of computer node data from one gateway to a second gateway during times of dysfunctioning of the one gateway. The redundancy routine changes access in a manner which is transparent to the host processor. A database is employed to hold computer node data for direct access by the host processor. The redundancy routine ensures the latest computer node data values to be reflected in the database.

Abstract: An overpressure-protected, differential pressure sensor (37) is formed by depositing diaphragm material (24) over a cavity (23) formed and filled with sacrificial material (22) into a front surface of a substrate. The sacrificial material (22) is then removed to create a free diaphragm. The floor of the cavity (23) defines a first pressure stop to limit the deflection of the diaphragm in response to pressure applied to the top of the diaphragm. A port (33) is created to allow pressure to be applied to the bottom side of the diaphragm (24). An optional second pressure stop, which limits the deflection of the diaphragm in response to pressure applied to the bottom side of the diaphragm, is formed by bonding a cap (35) to standoffs (34) placed around the top of the diaphragm. The standoffs are spaced to allow pressure to be applied to the top of the diaphragm.

Abstract: Radiant energy is transmitted to a probe element including an interior conical reflecting surface and a fluid sample chamber. Portions of the light which have been transmitted, partially attenuated, or scattered by a fluid sample in the sample chamber are directed by at least a portion of the interior conical reflecting surface to means for collecting the transmitted, partially attenuated, or scattered light. A stilling valve incorporated into the probe element enables elimination of entrained gas bubbles from the chamber. A specific application of the probe is disclosed in which a titration analyzer is combined with electro-optic signal conversion and processing circuits and a probe according to the invention to provide titration colorimetric endpoint determination in measuring the free fatty acid content of a fluid such as a edible oil or fat.

Abstract: An improved electrode cleaning system for an electrochemical sensor is disclosed. The improved electrode cleaning system includes a flexible wiper blade which is biased against a flat wiping surface formed by electrodes having a flat detection surface and a collar placed around the electrodes to prevent particulates from depositing between the electrodes. The collar is secured to the sensor by a recessed screw which also serves as a common electrical ground. The flexible blade preferably has two wiping portions for alternately wiping the electrodes and the common ground screw.

Abstract: A flex circuit connector assembly of the present invention includes folding one end of a flex circuit having contact pads to form a male contact portion. The male contact portion is then inserted into a female socket of an edge connector for electrically interconnecting the contact pads of the flex circuit to mating contacts disposed in the female socket of the edge connector. The edge connector includes pins for mounting it to a receptacle of a wired circuit.

Abstract: A solid state measurand sensor is described in which the pressure sensor element is protected from the measurand by a combination of a pressure transfer medium and a thin covering membrane. A method is described for forming the diaphragm in situ. The diaphragm material is selected from a group of materials which includes fluorosilicone, so as to substantially avoid entrapment of air or formation of voids in the pressure transfer medium such as would degrade the performance of the sensor. The pressure transfer medium is gel-like material such as dimethyl silicone and equivalents. Alternatively, the gel may be fluorosilicone and the diaphragm may be dimethyl silicone. The membrane material is chosen to be substantially impermeable to the ambients or process media being measured and also flexible, is to be poured and cured in place on the assembly during fabrication.

Abstract: A micromechanical electric shunt is fabricated by micromachining according to recent IC fabrication procedures. A plurality of such shunts is incorporated on a single substrate to form novel process station or post identification or signature encoding apparatus for use on a telecommunications bus or the equivalent. Such identification of signature encoding apparatus may be configured for conventional binary coding. Both frequency and current derivative mode apparatus are disclosed.

Abstract: A gas detector for detecting a combination of at least three gasses employs an optical filter having a spectral passband shaped and positioned to produce substantially equal responses from a single detector to a given concentration of any single one of the gasses or to a concentration any two or more of the gasses. A filter spectrum encloses substantially equal areas of the absorption spectra of the gasses. The filter includes a spectral bandwidth, cut-on maximum wavelength, cut-on slope, cut-off maximum wavelength and cut-off slope, adjusted for controlling the areas of the gas absorption spectra enclosed therein.

Abstract: It has been discovered that vortex flowmeters can be suitably adapted for the measurement of two-phase fluid flows, and particularly for the measurement of steam quality, when disposed in a particular manner in horizontal flowpipes carrying such fluids. More specifically, the invention disclosed includes the disposition of a substantially linear vortex flowmeter horizontally and transversely in a horizontal flowpipe to measure two-phase fluid flows, for example, wet steam quality. When the mass flow rate is not determinable through knowledge of the feedstock, other sensors enable measurement of the vapor phase volumetric area and velocity to permit calculation of the flow measurand.

Abstract: The invention comprises a Schottky barrier type infrared photodetector which is monolithically integrated on a silicon waveguide. A Schottky barrier contact is positioned directly on a silicon waveguide to absorb grazing incidence optical signals passing through the waveguide. The Schottky contact is operated in the avalanche or reverse bias mode to generate a useable electrical signal.

Abstract: A process controller may incorporate statistical computations of the variance in the controlled variable. Statistical measures may then be used to offset the controller set point to maintain the controlled variable distribution in an acceptable specification zone. The statistical measures may be made automatically and continuously thereby obviating human intervention, while producing high quality, though statistically variable, process output. The statistical measures may be calculated specifically or generated by a weighted integration method.

Abstract: Floating the diaphragm portion of a diaphragm sensor in the pressurizing fluid frees the diaphragm from exterior housing forces, and makes overall manufacture and replacement inexpensive. A diaphragm can be protected from exterior stress by interspersing a channel between the diaphragm edge and the closure and support structure of an enclosing housing. By extending the channel and incorporating an adequate seal, the diaphragm structure may be made replaceable. The replaceable diaphragm further allows use of a smaller amount of costly materials, and makes repair less costly.

Abstract: A method of fabricating low loss silicon optical waveguides by high energy ion implantation which converts a buried region into dielectric material. The top silicon surface can them be etched or formed into waveguides that are isolated by the buried dielectric. Annealing of the top silicon layer can be used to improve optical quality and additional silicon can be added to the top surface waveguides by epitaxial growth.