Abstract: A multi-stage axial compressor arrangement is disclosed that uses a compressor speed reducer to rotate the moving blades in the forward stages of the compressor at a slower rotational speed than the moving blades in the mid stages and the aft stages of the compressor. Slowing the rotational speed of the moving blades in the forward stages in relation to the blades in the mid stages and the aft stages, enables the multi-stage axial compressor to deliver a high airflow rate while overcoming excessive attachment stresses that is typically experienced in the large rotating blades of the forward stages of the compressor.

Abstract: A turbine section of a gas turbine engine according to an example of the present disclosure includes, among other things, a fan drive turbine section and a second turbine section. The fan drive turbine section has a first exit area at a first exit point and is configured to rotate at a first speed. The second turbine section has a second exit area at a second exit point and is configured to rotate at a second speed, which is faster than the first speed.

Abstract: Power train architectures with low-loss lubricant bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator each include rotating components, at least one of the rotating components in at least one of the compressor section, the turbine section, and the generator including a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a low-loss bearing having a low-loss lubricant.

Abstract: Mechanical drive architectures can include a gas turbine having a compressor section, a turbine section, and a combustor section. A load compressor is driven by the gas turbine. A rotor shaft extends through the gas turbine and the load compressor. At least one of the rotating components in one of the gas turbine and the load compressor includes a low-density material. Bearings support the rotor shaft within the gas turbine and the load compressor, at least one of the bearings being a low-loss lubricant bearing.

Abstract: Power train architectures with hybrid-type low-loss bearings and low-density materials are disclosed. The gas turbine used in these architectures can include a compressor section, a turbine section, and a combustor section coupled to the compressor and turbine sections. A generator, coupled to the rotor shaft, is driven by the turbine section. The compressor section, the turbine section, and the generator include rotating components, at least one of which is a low-density material. Bearings support the rotor shaft within the compressor section, the turbine section and the generator, wherein at least one of the bearings is a hybrid-type low-loss bearing.

Abstract: A heat storage mechanism, of a heat exchanger, which does not shorten the service life of the heat exchanger even when a facility using the heat exchanger is intermittently operated and which suppresses a decrease in efficiency at the time of restart of the facility, is provided. The heat storage mechanism for storing heat of a heat exchanger during stop of operation of a facility provided with the heat exchanger includes an outflow prevention unit configured to prevent outflow of an exhaust gas to the outside, which is a heating medium of the heat exchanger, during stop of operation of the facility is provided in an exhaust passage through which the exhaust gas is discharged to the outside.

Abstract: A cooling fluid system for a gas turbine engine includes a fluid source. A turbine section includes first and second components. A fluid supply system has a primary pipe that is configured to provide a cooling supply fluid from the fluid source to a fluid fitting having a fluid junction. The fluid junction is in fluid communication with and is configured to supply a first cooling fluid to the first component. The fluid junction is in fluid communication with and is configured to supply a second cooling fluid to the second component. A flow meter is upstream from the fluid junction and is configured to receive the cooling supply fluid.

Abstract: A gas turbine system (1) including a burner arrangement having a tubular combustion chamber (5), a turbine (6) and a transition duct (7) connecting the combustion chamber (5) and the turbine (6), wherein the transition duct (7) is provided with an axially extending cooling air channel (11). The transition duct (7) includes a plurality of axially extending cooling air channels, and wherein each cooling air channel (11) is provided with one single inlet (12) opened to the outside of the transition duct (7) and with one single outlet (12) opened to the inside of the transition duct (7).

Abstract: A bushing includes a body extending from a first end to a second end through an intermediate portion. The body includes a passage having a first centerline extending from the first end to the second end. A first alignment member is formed on a first section of the intermediate portion at the first end. The first alignment member includes an outer surface having a plurality of splines configured to be received by a first component to be joined. A second alignment member is formed on a second section of the intermediate portion. The second alignment member includes a second centerline that is off-set relative to the first centerline and is configured to be received by a second component to be joined with the first component.

Abstract: A gas turbomachine nozzle includes a base portion having a first fluid inlet and a second fluid inlet, and an outlet portion having one or more outlets. A connection section fluidically connects the base portion and the outlet portion. An orifice plug is arranged in the base portion at the second fluid inlet. The orifice plug includes one or more openings fluidically connecting the second fluid inlet and the connection section.

Abstract: A fuel nozzle for a gas turbine engine. The nozzle has a body and a center axis. The body has an inner circumferential surface circumscribing a central passageway which is coaxial with the center axis. The nozzle also has air passages which extend predominantly radially inward through the body. The air passage outlets of each air passage are circumferentially spaced apart from one another along the inner circumferential surface. Each air passage conveys air through the body toward the nozzle center axis and into the central passageway. The nozzle also has fuel passages which extend through the body. Each fuel passage is disposed within the body between adjacent circumferentially spaced apart air passages and is transverse to the direction of extension of its neighboring air passages.

Abstract: A gas turbine engine having a combustor that includes: an inner radial wall defining axially stacked first and second interior chambers, wherein the first interior chamber extends axially from an end cover to a fuel nozzle, and the second interior chamber extends axially from the fuel nozzle to an inlet of the turbine; and an outer radial wall formed about the inner radial wall so to form a flow annulus therebetween. The flow annulus may include a flow conditioning section that has: conditioning passages defined therethrough for directing a flow from inlets formed at an upstream end to outlets formed at a downstream end of the flow conditioning section; and structure rigidly attaching the inner radial wall to the outer radial wall.

Abstract: A downstream nozzle for use in a combustor that includes an inner radial wall defining a combustion zone downstream of a primary nozzle and an outer radial wall surrounding the inner radial wall so to form a flow annulus therebetween. The downstream nozzle may include: an injector tube extending between the outer radial wall and the inner radial wall; a first plenum adjacent to the injector tube, and, inboard of the ceiling, a floor disposed between the inner radial wall and the outer radial wall. A feed passage may connect the first plenum to an inlet formed outboard of the outer radial wall and impingement ports may be formed through the floor of the first plenum.

Abstract: A gas turbine combustor assembly includes a primary combustion chamber in fluid communication with a primary fuel injector and a primary air inlet. A torch igniter is carried by the primary combustion chamber, and includes an auxiliary combustion chamber housing comprising a mixing chamber and a throat region converging downstream of the mixing chamber. An air swirler including a plurality of swirl openings surrounding an outlet of an auxiliary fuel injector is coupled to the auxiliary combustion chamber proximate the mixing chamber. An ignition source projects into the mixing chamber of the auxiliary combustion chamber.

Abstract: A starter-generator module for a gas turbine engine includes an inner stator portion with an armature defining a rotation axis and an outer rotor portion disposed about the rotation axis. The outer rotor portion includes a permanent magnet and a gear teeth member. The permanent magnet is disposed about the rotation axis and the gear teeth member is defined on the outer rotor portion such that the gear teeth member transmits rotational energy to an accessory gearbox in a start mode and receives rotational energy from the accessory gearbox in a generate mode.

Abstract: The present concept is method of controlling a vehicle's engine idle and includes the steps of monitoring a vehicles operating parameters with a controller and comparing parameters to preselected shutdown conditions. In the event shutdown conditions are met and the key is not in the ignition, the controller warns operator of impending shutdown. The controller intercepts the ignition key signal and simulates the vehicle key to be in the run position such that vehicle functions are operable as if key is in run position. The controller shuts down engine. The method may also include the steps of: the controller intercepting the ignition key signal and simulating the vehicle key to be in the accessory position such that vehicle functions are operable as if key is in accessory position.

Abstract: An vehicle with defined power on demand including a control system configured to provide to an operator a plurality of selectable features each have selectable options. The defined power on demand utilizes unrealized engine power which is limited by an engine control system for reasons of fuel savings and cost effectiveness. The selectable features include power take off (PTO), mechanical front wheel drive (MFD), front hitch, and rear hitch. Selectable options include a plurality of defined amounts of power delivered by a vehicle engine over a period of time with respect to a selected feature. The defined amount of power is greater than the power at which the engine typically operates as limited by the engine control system. The greater power is provided over a period of time to complete each of the selectable features.

Abstract: A method for redundantly controlling a speed of an internal combustion engine, in particular of a vehicle, which includes a redundantly actuatable actuator for adjusting the speed, the method includes the following steps: detecting a first actual speed and a second actual speed of the internal combustion engine, wherein the actual speeds are detected simultaneously and independently of one another; detecting a first actual position and a second actual position of the actuator, wherein the actual positions are detected simultaneously and independently of one another; determining a plausible actual speed and a plausible actual position in accordance with the detected actual speeds and/or the detected actual positions; and actuating the actuator for adjusting the speed in accordance with the plausible actual speed and the plausible actual position.

Abstract: An object is to provide an exhaust-gas control device for a gas engine whereby NOx is reduced and fuel consumption is improved by performing NOx restriction operation when an environmental or geographical condition in which the amount of NOx emission needs to be temporarily restricted is satisfied, and otherwise performing stable operation focusing on the fuel consumption.

Abstract: Embodiments for inducing swirl upstream of a compressor are provided. In one example, a method includes during a first condition, flowing exhaust gas from downstream of a turbine to upstream of a compressor via a tangential flow duct of an exhaust gas recirculation (EGR) injector circumferentially surrounding an intake passage upstream of the compressor, and during a second condition, flowing exhaust gas from downstream of the turbine to upstream of the compressor via a radial flow duct of the EGR injector.

Abstract: A method is provided for determining fuel blend in a dual fuel mixture including a first and a second fuel in an internal combustion engine. The method includes the steps of measuring multiple engine parameters using sensors during transient cycle operation for a predetermined range of engine loads and fuel blends; using system identification of transient time series of the measurements to determine one or more relevant engine parameters; determining a model for estimation of the fuel blend based on said one or more engine parameters; using the model fur determining a current fuel blend during transient operation using current measured values of the one or more engine parameters, and using the calculated current fuel blend for controlling the amount of dual fuel mixture injected into each cylinder of the internal combustion engine. A vehicle and a computer program product using the method are also provided.

Abstract: Systems and methods for implementing regeneration of an aftertreatment component using exhaust gas recirculation is described. According to various embodiments, an engine system comprises an engine, a turbocharger, a fluid control valve, and a lean NOx catalyst. The engine has a first set cylinders fluidly coupled to an intake manifold and a second set of cylinders having fluidly isolated from the intake manifold of the engine. The fluid control valve is disposed between the first exhaust outlet and the exhaust conduit and is structured to selectively fluidly couple the first exhaust outlet to the exhaust conduit. Also, the lean NOx catalyst has an inlet structured to receive exhaust gases from the exhaust conduit at a position downstream of the turbine outlet and the fluid control valve.

Abstract: An object is to provide a method and a system of controlling a load during misfire of an engine, whereby additional stress on a crank shaft is calculated from torsional vibration of the crank shaft to obtain an output limit rate, and an operation output of an engine is controlled on the basis of the output limit rate.

Abstract: An indicated mean effective pressure (IMEP) module determines IMEPs for combustion cycles of cylinders of an engine, respectively. A coldstart indication module indicates whether the engine is in a cold state after a startup of the engine. A fueling correction module, when the engine is in the cold state, selectively increases a fueling correction for one of the cylinders based on the IMEP of the one of the cylinders. An equivalence ratio (EQR) module selectively increases an EQR of the one of the cylinders based on the fueling correction for the one of the cylinders.

Abstract: A method involves controlling a fuel injector to inject a first quantity of a fuel into a cylinder from a plurality of cylinders, of an engine and detecting a first value of a parameter associated with the engine. The method further involves controlling the fuel injector to inject a second quantity of the fuel different from the first quantity of the fuel, into the cylinder of the engine and detecting a second value of the parameter associated with the engine. The method also involves comparing the first value with the second value and detecting a hardware anomaly associated with the engine based on the comparison of the first value with the second value.

Abstract: An object of the invention is to reduce an injection quantity of minimum by reducing difference in machines of fuel injection valves and difference in injection quantities of fuel injection valves caused by difference in characteristics. A fuel injection valve drive unit includes a unit that individually sets drive current waveform profiles according to cylinders, and includes a unit that individually sets drive current waveform profiles of the fuel injection valves on the basis of identification information based on injection quantity characteristics of the fuel injection valves.

Abstract: A method of remanufacturing an engine block is provided. An insert is removed from a recess in a top deck of the engine block that surrounds a cylinder bore in the engine block. A used cylinder liner is removed from the cylinder bore. The used cylinder liner has a flange on an upper edge thereof having a first thickness. The recess in the top deck of the engine block is cleaned. A replacement cylinder liner is positioned in the cylinder bore. The replacement cylinder liner has a flange on an upper edge thereof that is received in the cleaned recess. The flange of the replacement cylinder liner has a second thickness that corresponds to the sum of the first thickness and the depth of the cleaned recess.

Abstract: A system a cylinder head for a reciprocating engine. The cylinder head includes an ignition plug wall surrounding a bore configured to receive an ignition plug, where the ignition plug wall is integral to the cylinder head, the bore has a diameter, and the ignition plug wall has a thickness. The cylinder head also includes a cooling cavity completely separated from the bore via the ignition plug wall, where the cooling cavity has a radial width relative to an axis of the bore. The cylinder head further includes at least one of a first ratio of a minimum of the thickness versus a minimum of the diameter less than approximately 0.5 or a second ratio of a minimum of the radial width versus the minimum of the diameter less than approximately 0.5, or a combination thereof.

Abstract: The present invention relates to a thrust reverser cascade element of an aircraft gas turbine with a rigid frame and with several thrust reverser profiles mounted in the frame, wherein the thrust reverser cascade element is made of fiber-plastic composite.

Abstract: Actuator assembly includes a housing assembly, a ball screw, a ball nut, and a lock. The ball screw is rotationally mounted on and extends from the housing assembly, is coupled to receive an actuator drive torque, and is configured, upon receipt thereof, to rotate. The ball nut is rotationally supported on the ball screw and is configured, in response to rotation of the ball screw, to translate thereon between a stowed position and a deployed position. The lock is disposed at least partially within the housing assembly and is configured to move between a lock position and an unlock position. The lock prevents the ball nut from translating out of the stowed position when the lock is in the lock position and the ball nut is in the stowed position.

Abstract: Mechanical drive architectures can include a gas turbine having a compressor section, a turbine section, and a combustor section. A load compressor is driven by the gas turbine. A rotor shaft extends through the gas turbine and the load compressor. At least one of the rotating components in one of the gas turbine and the load compressor includes a low-density material. Bearings support the rotor shaft within the gas turbine and the load compressor, at least one of the bearings being a mono-type low-loss bearing.

Abstract: A fuel bowl for a carburetor system may include a fuel container and a fuel flow assembly that is removeably couplable thereto. The fuel container may include a base, a pair of sidewalls extending upwardly from the base, a rear wall extending upwardly from the base, a top overlying the pair of sidewalls and the rear wall, and a cavity defined by the pair of sidewalls and the rear wall. The fuel flow assembly may include a base, a pair of sidewalls extending upwardly from the base, a rear wall extending upwardly from the base, and a top overlying the pair of sidewalls and the rear wall.

Abstract: Methods and systems are provided for controlling and coordinating secondary air injection and blow-through to reduce turbo lag. By utilizing secondary air injection prior to providing blow-through, and deactivating the secondary air pump when a desired boost pressure for blow-through is achieved, turbine spin-up to a desired speed may be expedited and initial torque output may be increased.

Abstract: Systems and methods are provided for reducing surge in a boosted engine system. One method comprises adjusting an opening of a compressor recirculation valve to allow a compressor recirculation flow based on a combination of a nominal compressor recirculation flow and a filtered nominal compressor recirculation flow. The nominal compressor recirculation flow may be calculated as a difference between a desired compressor flow rate based on a surge limit of compressor and an estimated throttle mass flow rate.

Abstract: An engine includes a turbocharger, an air bypass valve, a wastegate valve, and an EGR apparatus. The engine also includes an ISC passage that connects an upstream side and a downstream side of a throttle valve in an intake passage, and an ISC valve that adjusts an amount of air flowing through the ISC passage. A control apparatus for the engine performs valve opening control to set an opening of an ISC valve at a larger opening than a reference opening when a required torque required by the engine is smaller than an estimated torque that can be generated by the engine, and closes the air bypass valve and the wastegate valve for a fixed period following completion of the valve opening control when an EGR valve of a low pressure EGR apparatus is opened during execution of the valve opening control.

Abstract: A thermal abatement system comprises an axial inlet, radial outlet supercharger. A main case comprises at least two rotor bores, an inlet plane and an outlet plane. The inlet plane is perpendicular to the outlet plane. An inlet wall comprises an inner surface. Two rotor mounting recesses are in the inner surface, and the inlet wall is parallel to the inlet plane. An outlet is in the outlet plane. An inlet is in the inlet plane. At least two rotors are configured to move air from the inlet to the outlet. The main case comprises at least two backflow ports. An intercooler is connected to receive air expelled from the supercharger, to cool the received air, and to expel the cooled air to the at least two back flow ports.

Abstract: Methods and systems are provided for operating exhaust valves of an engine to create more even exhaust pulses to a turbine. More specifically, the engine may include one or more dedicated exhaust gas recirculation (EGR) cylinders routing exhaust to an engine intake and one or more non-dedicated EGR cylinder routing exhaust to the turbine. In one example, a method may include operating a first set of exhaust valves of a group of non-dedicated EGR cylinders to have no exhaust valve opening overlap and operating an exhaust valve of a dedicated EGR cylinder so that opening of the second exhaust valve overlaps with opening of exhaust valves of two cylinders of the group of non-dedicated EGR cylinders.

Abstract: A centrifugal separator (1) for separating particles (2) from a fluid, having a guide apparatus (8) that has a housing (12) with an inflow opening (4) and an outflow opening (14), a core (18) accommodated in said housing (12) and guide blades (26) that are arranged between the core (18) and the housing (12), wherein the cross-sectional area (A) of the guide apparatus (8), through which the fluid flows through the guide apparatus (8), changes starting from the inflow opening (4) towards the outflow opening (14) in a flow direction (6) of the guide apparatus (8).

Abstract: A fuel injector has a seat and at least one seat passage. The seat includes an outer tip surface through which the seat passage extends. Fin structure is provided in the outer tip surface and is constructed and arranged to increase a surface area of the outer tip surface as compared to a surface area of the outer tip surface absent the fin structure. The outer tip surface, including the fin structure, is constructed and arranged to be heated by combustion gases so that the outer tip surface reaches a temperature greater than a temperature that the outer tip surface would reach absent the fin structure, so as to cause evaporation of fuel that contacts the outer tip surface.

Abstract: A heat transfer system for use in an internal combustion engine and related methods are disclosed. The heat transfer system may be configured to absorb and transfer heat from a combustion chamber of an internal combustion engine. The heat transfer system may also be configured to reintroduce absorbed and/or transferred heat into the internal combustion engine via a fuel injector or another suitable device. Removal of the heat from the combustion chamber may reduce a quantity of work required or used for compression of a first combustion fluid, increase a charge density in the combustion chamber, and/or increase the compression ratio of the engine. Additionally, the heat transfer system may be designed such that it may be used to retrofit an existing internal combustion engine.

Abstract: A heat transfer system for use in an internal combustion engine and related methods are disclosed. The heat transfer system may be configured to absorb and transfer heat from a combustion chamber of an internal combustion engine. The heat transfer system may also be configured to reintroduce absorbed and/or transferred heat into the internal combustion engine via a fuel injector or another suitable device. Removal of the heat from the combustion chamber may reduce a quantity of work required or used for compression of a first combustion fluid, increase a charge density in the combustion chamber, and/or increase the compression ratio of the engine. Additionally, the heat transfer system may be designed such that it may be used to retrofit an existing internal combustion engine.

Abstract: In a fuel injection valve having a nozzle hole plate wherein a nozzle hole is formed, the nozzle hole is formed with a flow path cross-section having an oval shape that has long axes and short axes, and the nozzle hole is formed having a tapered shape in which a flow path sectional area becomes larger from an entry-side open end portion toward an exit-side open end portion. The nozzle hole is formed such that a second angle that is an intersecting angle of opposing nozzle hole inner wall surface portions in an oblique section along the short axes of the entry-side open end portion and the exit-side open end portion, is greater than a first angle that is an intersecting angle of opposing nozzle hole inner wall surface portions in a longitudinal section along the long axes of the entry-side open end portion and the exit-side open end portion.

Abstract: A fuel system for an internal combustion piston engine includes a first fuel section and a second fuel section in which the first fuel section has a first inlet line connecting respective inlets of the injectors to a tank, and the second fuel section has a second inlet line connecting respective inlets of the injectors to a fuel tank. The second fuel section is arranged to inject the fuel into the combustion chambers for igniting the first fuel, in which first fuel section the inlet line extends from a high pressure pump to the respective injectors, and a fuel return line of the first fuel section extends from each of the injectors to the tank. The fuel return line has a pressure increasing means arranged to the fuel return line of the first fuel section between the injectors and the tank.

Abstract: Methods and systems are provided for controlling a remote start feature of an engine of a vehicle. A receiver is configured to receive a signal to initiate a remote start of the engine. A processor is coupled to the receiver, and is configured to initiate the remote start after receiving the signal; set a timer that measures an amount of time after which the remote start has been initiated, for a duration of the remote start; extend the remote start upon detection of an action by an individual proximate the vehicle before the amount of time exceeds a first predetermined threshold; and terminate the remote start after the amount of time exceeds the first predetermined threshold if no action has been detected during the duration of the remote start.

Abstract: The internal combustion engine ignition device has a core, a coil part that is wound over the core, and a secondary coil that is wound on the outer peripheral side of the coil part. A switching element switches an induced current, which is generated via the rotation of a permanent magnet, of a primary coil on and off. A resistor and a microcomputer are connected to the switching element, and a rotation detection circuit is connected to the microcomputer. The microcomputer drives the switching element so as to rapidly change the current flowing through the primary coil and generate a high voltage in the secondary coil, and generate a spark discharge in a spark plug connected to the secondary coil. In the coil part, one coil is divided by an intermediate tap, forming the primary coil and a charging coil.

Abstract: An internal combustion engine of the present invention is an internal combustion engine equipped with a supercharger that can switch between a lean combustion operation that combusts a mixture gas with an air-fuel ratio leaner than a theoretical air-fuel ratio, and a stoichiometric combustion operation that combusts a mixture gas with an air-fuel ratio close to the theoretical air-fuel ratio. Further, the internal combustion engine has an ISC passage that connects an upstream side and a downstream side of a throttle valve in an intake passage, and an ISC valve that regulates an amount of air flowing in the ISC passage.

Abstract: In a control apparatus for an internal combustion engine, which implements temperature increasing processing in which an ignition timing is retarded to a predetermined target ignition timing in order to increase an exhaust gas temperature, a period required for an actual ignition timing to become equal to the target ignition timing following the start of retardation of the ignition timing during the temperature increasing processing is lengthened when a startup torque, which is a torque generated by the internal combustion engine during a startup process, is small.

Abstract: It is possible to adjust electromagnetic energy introduced from a low-voltage side of a primary winding 20 of an ignition coil 2 after start discharging to a spark plug 1 from the ignition coil 2 in the correct proportion by threshold-determining either one or both of a primary voltage V1 applied to a primary side of the ignition coil 2 and a secondary current I2 flowing in a secondary side of the ignition coil 2, and by opening and closing a discharging switch 32 disposed between an auxiliary power supply 3 including an energy storage coil 330 and a low-voltage side terminal 201 of the ignition coil 2.

Abstract: An ignition system controlled by a powertrain controller via a dwell line carrying a dwell signal has a state machine to monitor a dwell period between consecutive dwell signals and to adjust a rate of a variable clock signal accordingly. A multi-bit counter is clocked by the adjusted clock signal. The counter has a first set of bits to establish an integration period and a second set of bits coupled to a resistive ladder generating a stair step signal. A current sensor provides a current signal proportional to the ion current. A comparator compares the current signal to the stair step signal. An ion current counter is incremented during the integration period whenever the current signal indicates an ion current magnitude greater than the stair step signal. The accumulated count at the end of the integration period is reported to the powertrain controller as a measure of the ion current.

Abstract: A water current power generation system is provided, including at least one or more submerged flotation chambers; one or more submerged induction type power generation units disposed in communication with the one or more submerged flotation chambers; one or more impellers disposed in communication with the one or more submerged induction type power generation units; one or more body frame members disposed in communication with the one or more submerged induction type power generation units; and one or more impeller rotation means disposed in communication with the one or more body frame members. A variety of additional structures useful together, individually or in various combinations with the disclosed system, are also disclosed. Methods of transporting and maintaining the system, or individual components and subsystems thereof, are also disclosed.