Abstract: The present invention provides a refrigerant composition comprising: (a) from about 65% by weight to about 90% by weight of HFO-1234ze(E); (b) from about 10% by weight to about 35% by weight of HFO-1336mzz (E); and optionally (c) from about 0% to about 4.4% by weight of HFC-227ea for use in a variety of refrigeration applications, including air conditioning and/or refrigeration and particularly cooling products such as fruits, vegetables and beverages without exposing those articles to temperatures below the freezing point of water.

Abstract: Systems and methods for a dual-interrogated interferometer for fluid measurements are described herein. In some embodiments, a system includes an interferometer that provides interfered light having interference fringes, wherein the interfered light comprises emitted light from the system interfered with received light by the system. The system also includes a high-rate sensor that detects the interfered light to create high-rate measurements. Further, the system includes a two-dimensional detector array that detects the interfered light to create two-dimensional detector array measurements. Moreover, the system includes one or more processors that calculate fluid velocity in relation to the system based on a mapping of the high-rate measurements to the two-dimensional detector array measurements.

Abstract: Techniques relating to a micro-electro-mechanical (MEMS) device configured to measure direct axial and shear stress components of a stress tensor are described. The MEMS device includes a first and second circuit configured in a double rosette structure coupled with a third circuit in a standard rosette structure to form a triple rosette piezo-resistive gauge circuit. The first circuit includes at least one piezoresistive element suspended from a substrate, and at least one piezoresistive element fixed to the substrate. The second circuit includes each piezoresistive element fixed to the substrate. The third circuit includes at least one piezoresistive element fixed to the substrate. Additionally, the MEMS device may be coupled to one or more processing systems to determine a mechanical stress tensor that is applied to the MEMS device based on measurements received from the MEMS device.

Abstract: Methods and systems are provided for assisting operation of a vehicle deviating from a desired manner of operation, such as an aircraft deviating from a planned trajectory. One method involves identifying a current aircraft altitude, identifying a current aircraft configuration, determining a recommended flight path from the current aircraft altitude for satisfying an upcoming constraint associated with a reference descent strategy based at least in part on the current aircraft configuration in response to a deviation between the current aircraft altitude a target altitude according to the reference descent strategy, and providing an output influenced by the recommended flight path. The recommended flight path includes a recommended vertical profile and a recommended speed profile, and the recommended flight path is configured to vary at least one of a kinetic energy or a potential energy of the aircraft along the recommended flight path en route to the upcoming constraint.

Abstract: A ram air turbine rotor comprises at least one intra-flow path shroud structure coupled between rotor blades, along a radial position between a support disc and an outer rim. The shroud structure includes shroud sectors each coupled between a respective pair of blades. The sectors each include a first edge adjacent to leading edges of the respective pair of blades, the first edge including a first curved segment, and a second edge adjacent to trailing edges of the respective pair of blades, the second edge including a second curved segment. The curved segments are each partially defined by a respective ellipse having a semi-major axis and a semi-minor axis. The semi-major axis is a portion of a spanwise distance between the respective pair of blades. The semi-minor axis is a portion of an axial distance between the leading edge of one blade and the trailing edge of an adjacent blade.

Abstract: Disclosed are hearing protection devices and housings for noise sensors for the same. Hearing protection devices can include an ear cup including an external casing partially defining an inner space, a noise sensor including a microphone electrically coupled to a printed circuit board, and a housing disposed in an aperture defined in the external casing. The housing can define an axial bore defining a noise sensor receiving portion and an acoustic communication portion. The inner space of the ear cup can be substantially airtight when the housing is sealably disposed at or proximate the aperture, the microphone is engaged within the noise sensor receiving portion of the housing, and the ear cup is worn securely about the wearer's ear. The noise sensor can be calibrated by removing a removable securing collar and slidably disposing a calibration tool into the axial bore without further disassembling the hearing protection device.

Abstract: A temperature-variable standoff includes a temperature-variable electrical element. The standoff also includes a support body that supports the temperature-variable electrical element and that is configured to support a circuit board separated at a distance from another component of an electronics assembly. The support body is configured to attach to the circuit board and to project away from the circuit board with a first end proximate the circuit board and a second end spaced away from the circuit board. The standoff further includes an electrical connector supported proximate the first end. The electrical connector is configured to electrically connect within an electrical circuit of the circuit board to provide the electrical input to the temperature-variable electrical element for selectively varying the temperature thereof.

Abstract: Systems and methods for integrity monitoring of primary and derived parameters are described herein. In certain embodiments, a method includes transforming an estimated error state covariance matrix of at least one primary integrity monitoring parameter of a navigation system onto an error state covariance matrix of one or more derived integrity monitoring parameters, wherein the one or more derived integrity monitoring parameters depends from the at least one primary integrity monitoring parameter. The method also includes transforming an integrity threshold of the at least one primary integrity monitoring parameter onto separation parameters of the one or more derived integrity monitoring parameters. The method further includes computing a protection limit for the one or more derived integrity monitoring parameters.

Abstract: The system a gas meter configured to determine a meter health factor based on a power management criteria, ageing criteria, wear out criteria, accuracy impacting criteria, and an alarm state. The gas meter can determine if the meter health factor indicates if functioning is intact, if functioning is intact or assistance and repair is needed immediately or at a future time interval based on the power management criteria, ageing criteria, wear out criteria, accuracy impacting criteria, and an alarm state. The gas meter informs a head end system that the assistance and repair is required. The head end system receives information that the assistance and repair is required, and obtains the required assistance and repair from one or more external sources.

Abstract: A system and method for diagnosing load compressor health state for an auxiliary power unit that includes a power compressor, a combustor, a power turbine, and a load compressor is provided. The auxiliary power unit is operated and bleed air is discharged from the load compressor at a bleed air pressure. Using a pressure sensor, the bleed air pressure discharged from the load compressor is sensed and supplied to a processor. In the processor, power compressor health state is diagnosed based solely on the sensed bleed air pressure.

Abstract: In some examples, a braking system includes a housing configured to rotate around a torque tube. A disc stack includes a plurality of stator discs are coupled to the torque tube and a plurality of rotor discs rotationally coupled to the housing. An actuator within the torque tube is configured to compress the disc stack. A portion of the torque tube may be configured to insert into an axial assembly of a wheel. The housing may be connected to a portion of a wheel rim. The braking system may be present on a wheel instead of or in addition to a main braking system having a main disc stack.

Abstract: The present disclosure provides azeotrope or azeotrope-like compositions including trifluoroiodomethane (CF3I) and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), and a method of forming an azeotrope or azeotrope-like composition comprising the step of combining 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) and trifluoroiodomethane (CF3I) to form an azeotrope or azeotrope-like comprising 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) and trifluoroiodomethane (CF3I) having a boiling point of about ?22.70° C.±0.30° C. at a pressure of about 14.30 psia±0.30 psia.

Abstract: A method is provided for determining an operating state of a burner. The method includes receiving baseline characteristic data for a plurality of burner operating states. The baseline characteristic data for each burner operating state of the plurality of burner operating states comprises baseline data of a plurality of data types indicative of a corresponding burner operating state. The method also includes receiving monitoring data captured for a burner by a plurality of burner sensors. The method further includes using to machine learning to compare at least a portion of the monitoring data captured for the burner with the baseline characteristic data. The method still further includes determining an operating state of the burner based at least in part on results of comparing the at least a portion of the monitoring data with the baseline characteristic data. A corresponding apparatus and computer program product are also provided.

Abstract: Systems and embodiments for an integrated photonics mode splitter and converter are provided herein. In certain embodiments, a system includes a substrate having a first index of refraction. Additionally, the system includes a waveguide layer on the substrate, wherein the waveguide has a second index of refraction different from the first index of refraction. Also, the waveguide layer includes one or more mode splitters that receive at least one of a first photon in a first mode and a second photon in a second mode through an input port and provide one of the first photon through a first output port and the second photon through a second output port. The waveguide layer also includes a mode converter coupled to the second output of a mode splitter, wherein the mode converter receives the second photon through a port and outputs the second photon in the first mode through the port.

Abstract: A system for coupling a shroud to a case associated with a gas turbine engine and a gas turbine engine including such a system includes the case defining a bore and the shroud retained within the case. The shroud defines a pocket. The system includes a pin received through the bore and at least partially positioned within the pocket. The pin has a perimeter. The system includes a load spreader including a first side and a second side opposite the first side. The first side is interconnected to the second side by a flexible portion. The first side, the second side and the flexible portion are received about a portion of the perimeter of the pin, and the load spreader is configured to transmit at least one of an axial point load and a circumferential point load from the pin over a surface of the shroud.

Abstract: Improvements to optical power regulation in a gyroscopic system are described. The system can include an optical assembly (e.g., optical bench) which couples opposing optical signals to a resonator coil. The system can monitor the power of the optical signals through the resonator coil by including signal extraction optics in the optical assembly which are configured to extract a portion of the optical signals. The portions can be extracted via a single beamsplitter, wherein the beamsplitter reflects the portions at a single common surface, and can also reflect the portions to a respective photodetector in free space free from intervening optical components, such as polarizers or beamplitters. One or more processors can be coupled to the optical assembly, wherein the processor(s) are configured to adjust the power of the optical signals in response to detecting a power difference between the optical signals.

Abstract: A multilayer mirror comprises a reflector section including a plurality of alternating layers of a high index material and a low index material, and a filter section over the reflector section. The filter section comprises a first filter layer including a low index material on a layer of high index material of the reflector section; a second filter layer on the first filter layer, the second filter layer comprising a high index material that is different than the high index material in the reflector section; and a third filter layer on the second filter layer, the third filter layer comprising a low index material. Each filter layer has an optical thickness greater than or equal to the optical thickness of each layer of the alternating layers. The filter section substantially blocks ultraviolet (UV) energy, thereby preventing UV energy from substantially impinging on the high index material of the reflector section.

Abstract: A system and method of storing and recovering a flight plan includes loading flight plan data into working memory of an aircraft flight management system (FMS). When the FMS determines that a storage triggering event has occurred, a copy of at least a portion of the flight plan data is transmitted from the working memory to a non-volatile storage medium. A display command is supplied to a display device, at least following recovery of the FMS from a severe reset, that causes the display device to render a retrieval prompt. A retrieval command is received at the FMS, via a user input device, that causes the FMS to retrieve the at least a portion of the flight plan data from the non-volatile memory and store it in the working memory.

Abstract: Embodiments relating to an integrated photonics air data system are disclosed. A light beam from a laser source is routed to a plurality of tunable optical filters operative to transmit the light beam to one of a plurality of emitting grating couplers at any given time. The tunable optical filters are configured such that the light beam is emitted into the region of interest at different times from each of the emitting grating couplers. A passive optical filter array is configured to receive scattered light from the emitted light beam. The passive optical filter array comprises a plurality of optical notch filters operative for frequency selection, and a plurality of optical detectors each respectively coupled to an output of one of the optical notch filters. The passive optical filter array is operative to perform frequency spectrum decomposition of the received scattered light into a plurality of signals.

Abstract: A manufacturing method includes providing a material that includes a plurality of particles and a binder that is uncured. The method also includes forming a first article from the material including curing the binder to bind a collection of the particles together into the first article. Furthermore, the method includes encasing at least a portion of the first article with an outer member. The outer member defines an internal cavity that corresponds to the first article. Additionally, the method includes heating the outer member and the first article to melt the collection of particles into a molten mass within the internal cavity of the outer member. Moreover, the method includes solidifying the molten mass within the outer member to form a second article. The second article corresponds to at least a portion of the internal cavity of the outer member.