Abstract: A method of controlling an infant care device includes identifying, via a location tracking system, a device location of the infant care device within a care facility by locating a device location tag on the infant care device, and also identifying any local clinician tags worn by a clinician within a predetermined area around the device location. The local clinician tags are compared to a list of authorized clinician tags to identify whether at least one local authorized clinician tag is within the predetermined area around the infant care device. User input is received at a user interface associated with the infant care device to modify operation of the infant care device. Operation of the infant care device is modified based on the user input only if at least one local authorized clinician tag is within the predetermined area around the infant care device at the time of receiving the user input.

Abstract: A gas turbine engine includes: a compressor section including a compressor mean radius; a combustor section fluidly coupled downstream of the compressor section and include a combustor mean radius; and a turbine section fluidly coupled downstream of the combustor section and a turbine mid-span radius. The combustor mean radius is greater than each of the compressor mean radius and the turbine mid-span radius.

Abstract: A method for maintenance of a machine among a fleet of machines includes receiving a service request corresponding to the machine. The method also includes obtaining a service architecture corresponding to the fleet of machines. The service architecture includes a service dictionary and a plurality of classification schemes organized in a tree data structure. The method also includes processing the service request based on the service dictionary and a text parsing technique to generate a list of descriptive words. The method includes generating a recommendation based on the list of descriptive words and the service architecture. The recommendation includes at least one of an on-line repair activity, an on-site repair activity and a part replacement activity. The method also includes servicing the fault condition of the machine based on the recommendation.

Abstract: Methods for treating steel, along with the resulting treated steel, are provided. The method may comprise: nitriding a carburized Ferrium steel component such that the Ferrium steel component has a surface portion with a nitrogen content that is greater than 0% to about 5% by weight. Nitriding the Ferrium steel component may increase the surface hardness of the Ferrium steel. The surface portion may have a nitrogen content of about 0.05% to about 0.5% by weight.

Abstract: Embodiments are described which exploit a finding, according to which a higher compression rate or better rate/distortion ratio may be achieved by adopting or predicting second coding parameters used for encoding a second view of the multi-view signal from first coding parameters used in encoding a first view of the multi-view signal. In other words, the inventors found out that the redundancies between views of a multi-view signal are not restricted to the views themselves, such as the video information thereof, but that the coding parameters in parallelly encoding these views show similarities which may be exploited in order to further improve the coding rate.

Abstract: Methods and systems are provided for inferring thickness and volume of one or more object classes of interest in two-dimensional (2D) medical images, using deep neural networks. In an exemplary embodiment, a thickness of an object class of interest may be inferred by acquiring a 2D medical image, extracting features from the 2D medical image, mapping the features to a segmentation mask for an object class of interest using a first convolutional neural network (CNN), mapping the features to a thickness mask for the object class of interest using a second CNN, wherein the thickness mask indicates a thickness of the object class of interest at each pixel of a plurality of pixels of the 2D medical image; and determining a volume of the object class of interest based on the thickness mask and the segmentation mask.

Abstract: A method for operating a multi-level bridge power converter of an electrical power system connected to a power grid includes receiving, via a controller of the power converter, an indication of a transient event occurring in the power grid or the electrical power system. The power converter has a plurality of switching devices arranged in an active neutral point clamped topology. Accordingly, upon receiving the indication, the method includes activating a crowbar algorithm programmed in the controller of the power converter to bifurcate a current received by the power converter into a plurality of different current paths defined by the plurality of switching devices.

Abstract: A cascade thrust reverser assembly for a gas turbine engine includes a nacelle assembly defining a bypass passage. The cascade thrust reverser assembly includes a cascade assembly configured to be at least partially enclosed by the nacelle assembly, the cascade assembly comprising one or more cascade members, the one or more cascade members movable between a stowed configuration wherein the one or more cascade members define a first radial extent and a deployed configuration wherein the one or more cascade members define a second radial extent, wherein the one or more cascade members form a cascade segment in the deployed configuration, and wherein the second radial extent is greater than the first radial extent.

Abstract: Compaction systems and methods of compacting components are provided. In one aspect, a laminate of a component can be laid up on a tool of a compaction system. The laminate defines a cavity. A noodle is positioned relative to or in the cavity. A noodle ring is then positioned relative to the noodle. For instance, the noodle ring can be placed over the noodle. A cross section of the noodle ring can be shaped complementary to a cross section of the noodle. A plunger of the compaction system is moved so that it engages the noodle ring. Particularly, the plunger is moved in such a way that a force is applied on the noodle ring so that the noodle ring compacts the noodle into the cavity.

Abstract: A method for manufacturing a structural component of a blade segment for a rotor blade includes providing a mold of the structural component having an outer wall that defines an outer surface of the structural component. The method also includes laying up one or more fiber layers in the mold so as to at least partially cover the outer wall. As such, the fiber layer(s) form the outer surface of the structural component. Further, the method includes providing one or more metal mesh layers having one or more ends. Moreover, the method includes providing a cover material to the end(s) of the metal mesh layer(s). In addition, the method includes placing the metal mesh layer(s) with the covered end(s) atop the fiber layer(s). Thus, the method includes infusing the fiber layer(s) and the metal mesh layer(s) together via a resin material so as to form the structural component.

Abstract: A method for automatically controlling ventilation of a patient includes receiving a target expiratory CO2 concentration, measuring an actual expiratory CO2, and comparing the actual expiratory CO2 concentration to the target expiratory CO2. A ventilation rate for the patient is then calculated based on the comparison of the actual expiratory CO2 concentration and the target expiratory CO2 in order to maintain the actual expiratory CO2 within a predetermined range of the target expiratory CO2. The patient is then automatically ventilated based on the calculated ventilation rate.

Abstract: An apparatus and method for a reverse flow combustor, the reverse flow combustor including a straight portion, a dilution portion and a curved portion. The reverse flow combustor receives a flow of fuel that is ignited and mixed with cooling air to form a flow of combustion gases. The flow of combustion gases travels through the reverse flow combustor to a turbine section of an engine.

Abstract: A system comprising a processor configured to obtain a feature set for a component and generate random trees based on the feature set and a training data set, wherein each of the random trees can include at least one predictive value representing a probability of a feature of the random trees indicating a failure of the component within a period of time. The processor can also select a subset of the random trees based on the at least one predictive value, determine a likelihood of the failure of the component based on operational data for one or more devices and the subset of the random trees, and transmit an explanation to a remote device for the likelihood of failure of the component by indicating the feature selected from the subset of the random trees.

Abstract: A motorized apparatus includes a body assembly and a maintenance device mounted to the body assembly. The maintenance device is configured to perform a service operation on a surface. The maintenance device extends from the body assembly at an angle. The motorized apparatus also includes a plurality of leg assemblies coupled to the body assembly and configured to support the body assembly and the maintenance device at a distance from the surface. The motorized apparatus further includes at least one actuator assembly coupled to the plurality of leg assemblies and configured to independently actuate each leg assembly of the plurality of leg assemblies. The at least one actuator assembly is configured to receive instructions related to a position of the maintenance device and actuate the plurality of leg assemblies to adjust an orientation of the body assembly and the maintenance device relative to the surface.

Abstract: An engine component for a gas turbine engine, the engine component comprising a cooling architecture comprising at least one unit cell having a set of walls with a thickness, the set of walls defining fluidly separate conduits having multiple openings, each of the multiple openings having a hydraulic diameter; wherein the thickness (t) and the hydraulic diameter (DH) relate to each other by an equation: ( D H + 2 ? t ) 2 ( ( D H + 2 ? t ) / D H ) 1 / 3 to define a performance area factor (PAF).

Abstract: A load adaptive linear electrical generator system is provided for generating DC electrical power. The electrical generation system includes one or more power generation modules which will be selectively turned on or off and additively contribute power depending on the DC power demand. Each power generating module includes a pair of linear electrical generators connected to respective ones of a pair of internal combustion piston based power assemblies. The piston in the internal combustion assembly is connected to a magnet in the linear electrical generator. The piston/magnet assembly oscillates in a simple harmonic motion at a frequency dependent on a power load of the electrical generator. A stroke limiter constrains the piston/magnet assembly motion to preset limits.

Abstract: A wireless patient monitoring system includes at least one wireless physiological sensor having a sensing element senses physiological parameter information from a patient. A sensor controller is configured to determine a current parameter value based on the physiological parameter information and to compare the current parameter value to a prior parameter value. Based on the comparison, the sensor controller determines if the current parameter value is redundant of the prior parameter value. If so, then the current parameter value is not transmitted. If the current parameter is not redundant of the prior parameter value, then a wireless transmitter is controlled to wirelessly transmit the current parameter value.

Abstract: A method for damping sub-synchronous control interactions (SSCI) in a grid-forming inverter-based resource connected to an electrical grid includes receiving, via a controller, a current feedback signal in a synchronous reference frame. The method also includes rotating, via the controller, the current feedback signal to a new reference frame associated with a sub-synchronous frequency range. Further, the method includes determining, via the controller, a sub-synchronous component of the current feedback signal. Moreover, the method includes rotating, via the controller, the sub-synchronous component of the current feedback signal back to the synchronous reference frame. In addition, the method includes determining, via the controller, a voltage command associated with sub-synchronous damping for the inverter-based resource as a function of the sub-synchronous component and a virtual resistance setting.

Abstract: An apparatus may include a processor, memory modules, and machine-readable instructions stored in the memory modules. When executed by the processor, the instructions may cause the apparatus to receive image data of one or more laser strikes on a build plane, the image data indicating positions of a first set of fiducial strikes made by a first laser on the build plane and positions of a second set of fiducial strikes made by a second laser on the build plane, determine relative positions of the first set of fiducial strikes and the second set of fiducial strikes with respect to each other from the received image data, compare the determined relative positions of the first and second sets of fiducial strikes with respect to each other to expected relative positions of the first and second sets of fiducial strikes with respect to each other, and determine whether the first laser and the second laser are misaligned with respect to each other based on the comparison.

Abstract: A system includes a supply receptacle defining one or more supply receptacle sidewalls and an upwardly-facing receptacle opening, a piston positioned at least partially within the supply receptacle, where the piston, the upwardly-facing receptacle opening, and the one or more supply receptacle sidewalls at least partially define an interior space of the supply receptacle, and the piston is positionable between an extended position, in which the interior space has an extended volume, and a retracted position, in which the interior space has a retracted volume that is greater than the extended volume, and a dosing hopper positioned above and in selective communication with the interior space of the supply receptacle, where the dosing hopper is structurally configured to deliver build material to the interior space.

Abstract: A method for providing build material to an additive manufacturing system (100) includes moving the build material (10) from a dosing hopper (240) to an interior space defined by one or more supply sidewalls of a supply receptacle (110) and a piston (130) positioned within the supply receptacle (110), and moving the piston toward a working surface (102) of the additive manufacturing system, thereby moving build material within the interior space to the working surface.

Abstract: An apparatus and method for an aircraft flight management system configured to analyze a takeoff sequence for an aircraft, the aircraft slight management system comprising a memory storing runway information associated with the runway from which the aircraft will depart, one or more inputs configured to receive variables comprising real-time aircraft variables and real-time condition variables that influence an actual velocity of the aircraft, sensors for sensing the actual velocity of the aircraft; and a processor configured to compare a real-time takeoff value to a takeoff requirement value.

Abstract: The present disclosure relates to rotors for an electrical machine comprising a first type of permanent magnets, and a second type of permanent magnets, wherein the first and the second types of permanent magnets have a same magnetic strength, and wherein the first type of permanent magnets has a first temperature rating, and the second type of permanent magnets has a second temperature rating different from the first temperature rating. The present disclosure relates to generators, and in particular to wind turbines comprising such generators and to methods for selecting or providing magnets for permanent magnet rotors.

Abstract: A rotor assembly for an electric machine is disclosed. The rotor core has a cylindrical body defining an outwardly facing peripheral surface comprising a slotted portion including a set of slots defined by a set of rotor teeth projecting outwardly from the peripheral surface. Each rotor tooth comprises a respective first distal tip and a respective first radial length extending radially from a center point of the rotor core to the first distal tip. The peripheral surface further comprises a non-slotted portion defining a respective second radial length, extending radially from the center point of the rotor core to the outwardly facing peripheral surface. The first radial length is less than the second radial length.

Abstract: Systems, methods, and computer-readable media are disclosed for monitoring and diagnosing power system assets. An example method may include triggering, by a gateway device and at a first time, a capture of a first waveform from a first intelligent electronic device (IED) associated with a first asset in a power system. The method may also include transmitting, by the gateway device, the capture of the waveform to a remote device. The method may also include extracting fault features from the first waveform corresponding to different failure modes associated with the asset of the power system. The method may also include determining, based on the features extracted from first waveform, that a fault of a first fault mode has occurred in the asset. The method may also include providing an alert that the fault has been identified, wherein the alert initiates or otherwise facilitates a control action in the power system.

Abstract: A circuit (10) for draining at least one combustible fluid for a cavity of a turbine includes a drain (12) in fluidic communication with the at least one cavity, and a first isolation valve (14) and a second isolation valve (16) defining between them an isolation cavity (C) of a portion of the drain. A discharge line (18) is in fluidic communication with the isolation cavity (C) to allow the discharge of air out of the isolation cavity (C). A supply line (22) supplies pressurized fluid to the isolation cavity (C), and a supply valve (24) is arranged in the supply line (22) for regulating the supply of the isolation cavity (C) with pressurized fluid. A discharge valve (20) is arranged in the discharge line (18) for regulating the discharge of the gases out of the isolation cavity (C), and a device (26) is provided for determining a failure of the drainage circuit (10).

Abstract: Exhaust frequency mitigation apparatus, exhaust diffusers, and turbomachines are provided. An exhaust frequency mitigation apparatus includes a main body extending along an axial centerline from a base to a tip. the base defines a first diameter and the tip defining a second diameter. the main body converges from the first diameter to the second diameter with respect to the axial centerline. The base is configured to extend from an inner shell of a turbomachine exhaust diffuser. The exhaust frequency mitigation apparatus further includes at least one rib extending from a root coupled to the main body to a free end.

Abstract: The present disclosure relates to a cooling system that includes a superconducting unit and a reservoir configured to store liquid coolant to cool the superconducting unit. The cooling system also includes an auxiliary storage system that includes one or more storage tanks fluidly coupled to the reservoir. The auxiliary storage system is configured to provide additional coolant to the reservoir as well as receive and store coolant from the reservoir.

Abstract: A cleaning solution for a turbine engine includes water; a first organic acidic component that comprises citric acid; a second organic acidic component that comprises glycolic acid; isopropylamine sulphonate; alcohol ethoxylate; triethanol amine; and sodium lauriminodipropionate. The cleaning solution has a pH value between about 2.5 and about 7.0.

Abstract: The present disclosure relates to supporting structures for a central frame of a direct-drive wind turbine and methods for managing such structures. A supporting structure is configured to assume a deployed configuration and a stowed configuration. In the stowed configuration, the supporting structure has a shape and size such that the supporting structure can be introduced into the central frame from an outside. In the deployed configuration, the supporting structure has one or more increased dimensions with respect to the stowed configuration, and comprises a working platform.

Abstract: A decoder for decoding a data stream into which media data is coded has a mode switch configured to activate a low-complexity mode or a high-efficiency mode depending on the data stream, an entropy decoding engine configured to retrieve each symbol of a sequence of symbols by entropy decoding using a selected one of a plurality of entropy decoding schemes, a desymbolizer configured to desymbolize the sequence of symbols to obtain a sequence of syntax elements, a reconstructor configured to reconstruct the media data based on the sequence of syntax elements, selection depending on the activated low-complexity mode or the high-efficiency mode.

Abstract: A lightning bypass system for a blade (22) of a wind turbine (10), the lightning bypass system comprising a blade connector (110) comprising an electrically insulating material (114) and configured to be located substantially in a rotational axis (R) of a blade root (24) of a wind turbine blade (22). The blade connector (110) is configured to be electrically connected to a down conductor cable (100) of the blade (22), and comprises a core configured to be electrically connected to a first end (111) and a second end (112) of the blade connector (110). The present disclosure further relates to methods for providing lightning bypass systems and to wind turbine hub assemblies comprising a lightning bypass system.

Abstract: A root portion for a wind turbine blade includes a coupling flange configured for coupling the root portion to a hub of the wind turbine. At least one support element is fixedly attached directly to the coupling flange and defines a support plane for contacting a transport or storing surface. The at least one support element includes a block member having an arcuate inner surface that conforms to and is affixed directly to an outer circumference of the coupling flange, and an opposite outer surface that defines the support plane.

Abstract: A coated component having a composite substrate and a coating system disposed thereon is provided. The coating system is substantially non-porous such that hydrocarbon fuel or other carbonaceous fluids are prevented from contacting and impregnating the polymer matrix composite material. The coating system can include an aluminum layer or a film layer comprising a polyethylene film or a polypropylene film. Also provided is a composite fan casing for a gas turbine engine having a polymer matrix composite substrate and a coating system disposed thereon. Methods for forming a containment assembly of a gas turbine engine are provided.

Abstract: Various methods and systems are provided for a current trap. In one example, the current trap has a flat core made of a nonconductive material, a coiled wire having a plurality of turns winding around the flat spiral core, and one or more tuning capacitors physically attached to the flat core and electrically connected to the coiled wire to form a resonant circuit with the coiled wire.

Abstract: Methods, apparatus, systems, and articles of manufacture are disclosed to implement a low radius ratio fan blade for a gas turbine engine. A fan blade for a gas turbine engine includes an airfoil including a leading edge and a trailing edge extending between a root and a tip of the airfoil, a distance between the leading edge and the trailing edge defining a flow path length, a leading edge hub point defined by a radially innermost point of the leading edge, and an axial dovetail including a pair of opposed pressure faces, an axial length of the axial dovetail less than the flow path length, a top edge of the axial dovetail separating the pressure faces from the airfoil, the top edge of the axial dovetail radially outward of the leading edge hub point.

Abstract: A gearbox assembly includes a gear assembly that includes a planet gear, a pin disposed within the planet gear, a first sensor, and a second sensor. The first sensor is disposed within the pin and is configured to produce a signal indicative of a strain of the pin. The second sensor is disposed within the pin and is configured to produce a signal indicative of a vibration of the pin. Another gearbox assembly includes a gear assembly including a planet gear, a pin disposed within the planet gear, and a strain sensor. The strain sensor is disposed within the pin and is configured to produce a signal indicative of a strain of the pin. The strain sensor is located within the pin at a circumferential location of the pin that is opposite to a location of a force acting on the pin when the planet gear rotates about the pin.

Abstract: A gas turbine is provided, the gas turbine engine including a turbomachine having an inlet splitter defining in part an inlet to a working gas flowpath and a fan duct splitter defining in part an inlet to a fan duct flowpath. The gas turbine engine also includes a primary fan driven by the turbomachine defining a primary fan tip radius R1, a primary fan hub radius R2, and a primary fan specific thrust rating TP; and a secondary fan downstream of the primary fan and driven by the turbomachine, the secondary fan defining a secondary fan tip radius R3, a secondary fan hub radius R4, and a secondary fan specific thrust rating TS; wherein the gas turbine engine defines an Effective Bypass Area, and wherein a ratio of R1 to R3 equals R 1 R 3 = ( E ? F ? P ) ? ( 1 - RqR Sec . - Fan 2 ) ( 1 - RqR Prim . - Fan 2 ) ? ( T P T S ) ? ( E ? B ? A ) .

Abstract: An aircraft equipped with a distributed fan propulsion system and methods of operating such aircraft are provided. In one aspect, an aircraft includes a wing having a top surface and a bottom surface. The aircraft also has a distributed propulsion system that includes a suction fan array having one or more fans mounted to the wing and a pressure fan array having one or more fans mounted to the wing. The fans of the suction fan array are each positioned primarily above the top surface of the wing and the fans of the pressure fan array are each positioned primarily below the bottom surface of the wing. The fans of the suction fan array are controllable independent of the fans of the pressure fan array so that the air pressure above and/or below the wing can be locally controlled, allowing for adjustment of lift on the wing.

Abstract: An air-to-air heat exchanger in flow communication with a gas turbine engine is provided. The air-to-air heat exchanger has an air-to-air heat exchanger potential defined by a product raised to a half power, the product being a heat transfer surface area density associated with the air-to-air heat exchanger multiplied by an airflow conductance factor associated with the gas turbine engine. The air-to-air heat exchanger potential is between about 6.7 and 19.5 for a bypass ratio associated with the gas turbine engine between about 3 and 10 and the heat transfer surface area density being between about 3,000 m2/m3 and 10,000 m2/m3 and is between about 2.9 and 12.2 for a bypass ratio associated with the gas turbine engine between about 10 and 20 and the heat transfer surface area density being between about 1,000 m2/m3 and 10,000 m2/m3.

Abstract: An anesthesia vaporizer system includes a vaporizer reservoir forming a sump chamber that contains liquid anesthetic agent and a fill chamber isolated from the sump chamber configured to receive liquid anesthetic agent from a refill container. A piston is in the sump chamber configured to maintain a constant force on the liquid anesthetic agent in the sump chamber, and a transfer valve is configured to permit the liquid anesthetic agent to flow from the fill chamber to the sump chamber. The vaporizer reservoir has an outlet port that delivers the liquid anesthetic agent from the sump chamber to a vaporizing system that vaporizes the liquid anesthetic agent for delivery to a patient.

Abstract: An additive manufacturing apparatus includes: a build table, at least a portion of which is transparent, the build table defining a build surface; a material applicator operable to deposit a radio-energy-curable resin on the build surface; a stage positioned facing the build surface of the build table and configured to hold a one or more cured layers of the resin; one or more actuators operable to change the relative positions of the build table and the stage; a radiant energy apparatus positioned adjacent to the build table opposite to the stage, and operable to generate and project radiant energy on the resin through the build table in a predetermined pattern; a drive mechanism operable to move the build table so as to expose a new portion thereof for each layer; and material remover operable to remove remnants from the build surface. A method for using the apparatus is provided.

Abstract: The present invention provides a high voltage direct current (HVDC) transmission system (300, 600) comprising: a first station (102) comprising series-connected first and second HVDC converters (110, 130); a second station (104) comprising series-connected third and fourth HVDC converters (150, 170), wherein a neutral node (164) coupling the third HVDC converter (150) to the fourth HVDC converter (170) is coupled to earth; a first transmission line (200) connecting a positive node (114) of the first HVDC converter (110) to a corresponding positive node (154) of the third HVDC converter (150), wherein a first pole (240) of the system (300, 600) comprises the first HVDC converter (110), the third HVDC converter (150) and the first transmission line (200); a second transmission line (210) connecting a negative node (138) of the second HVDC converter (130) to a corresponding negative node (178) of the fourth HVDC converter (170), wherein a second pole (250) of the system (300, 600) comprises the second HVDC conve

Abstract: Methods, apparatus, systems, and articles of manufacture are disclosed for a slot to accommodate a blade of an engine. An example blade apparatus includes: a collet including a slot to receive an end of a blade; and a plurality of retainers including a first retainer positioned on a first end of the collet and a second retainer positioned on a second end of the collet to provide axial retention for the blade in the slot.

Abstract: Methods and apparatus to reduce deflection of an airfoil are disclosed. An example apparatus disclosed herein includes a plate including an aperture, the airfoil disposed in the aperture, and a damper operatively coupled between the plate and a hub of the airfoil, the damper to transform flexural deflection of the airfoil to radial deflection of the plate.

Abstract: A computing system for an unducted rotor engine with a variable pitch vane assembly in aerodynamic relationship with an unducted rotor assembly, including a sensor-based controller configured to execute a first set of operations and a model-based controller configured to execute a second set of operations. The first set of operations includes obtaining a first signal corresponding to a commanded low spool speed; obtaining a second signal indicative of a pitch angle corresponding to thrust output from the unducted rotor assembly and variable pitch vane assembly; generating a pitch feedback signal corresponding to a commanded adjustment to the pitch angle based at least on one or both of a variable blade pitch angle or a variable vane pitch angle. The second set of operations include obtaining a desired thrust output via a throttle input; determining, at least via a power management block, a commanded thrust output signal; receiving the commanded thrust output signal; and generating an output signal.

Abstract: Various methods and systems are provided for stationary CT imaging. In one embodiment, an imaging system comprises a stationary distributed x-ray source unit comprising a plurality of emitters positioned to emit x-ray beams through the imaging volume, one or more detector arrays extending around at least a portion of an imaging volume, each detector array comprising a plurality of detector elements, each detector element configured to receive x-ray beams from more than one emitter, and an anti-scatter device configured to be positioned between one or more emitters of the plurality of emitters and an object in the imaging volume.

Abstract: The present disclosure relates to systems and methods for monitoring and guiding patient motion during medical image acquisition. In accordance with certain embodiments, a method includes acquiring an image of a patient with an imaging system; determining an amount of patient movement; and providing a movement indicator based on the determined amount of patient movement.

Abstract: A turbofan engine having one or more heat exchangers tied to an accessory gearbox is provided. The accessory gearbox is mechanically coupled with a spool, and a hydraulic pump is mechanically coupled with the accessory gearbox. The one or more heat exchangers have a heat exchanger capacity defined by a product raised to a half power, the product being determined by multiplying a resultant heat transfer surface area density of the one or more heat exchangers by a heat conductance factor that relates an accessory gearbox heat load, a power of the hydraulic pump, a diameter of a fan, and a bypass ratio of the turbofan engine. The heat exchanger capacity is between 23.9 and 97.7 for a rotational speed of the spool between 7,500 and 35,000 revolutions per minute at one hundred percent capacity and a resultant heat transfer surface area density being between 4,000 m2/m3 and 13,000 m2/m3.