88 results about "Transport delay" patented technology

System and method for synchronizing clocks and maintaining packet timing relationships in a wireless communications system. A preferred embodiment further comprises periodically synchronizing local clocks at a transmitter and a receiver to a clock reference, adding a timestamp to each application packet at a transmitter of a wireless network, setting the timestamp to a value of a local time at the transmitter plus a link delay, buffering a received packet at a receiver, and releasing the buffered packet to an application level when a value of a local time at the receiver equals the timestamp value in the packet. This can help to ensure that the timing relationships between data packets present at a transmitter is maintained at a receiver, regardless of transport delays (waiting, transmission and processing) incurred by the data packets.

A method for stream synchronization of real-time multimedia transport over a packet network, in which the multimedia includes a first stream and a second stream which are buffered and played through buffers. The method includes: measuring average transport delays of the first and second streams; measuring transport delay jitters of the first and second streams; and calculating a delay difference between the first and second streams which corresponds to the average transport delays and the transport delay jitters of the first and second streams, and setting buffer durations. A device for stream synchronization of real-time multimedia transport over a packet network is also provided.

A method for programming the delay for a node in a communication system is disclosed. The node receives a selected delay value and a signal path delay value indicating a delay for signals communicated to the node. The signal path delay comprises an aggregation of transport delays calculated by each node for segments of the communication system between the node and a host node. The method further calculates an additional delay necessary to meet the selected delay value.

An improved individual cylinder fuel control method based on sampled readings of a single oxygen sensor responsive to the combined exhaust gas flow of several engine cylinders. The oxygen sensor output is sampled in synchronism with the engine firing events, a stored non-volatile table of offset values is used to correlate the sampled oxygen sensor values with individual engine cylinders, and a new offset value is determined and stored in place of a current offset value when the current offset value fails to reduce a measure of air / fuel ratio maldistribution among the engine cylinders. In systems having an oxygen sensor of the switching type, the measure of air / fuel ratio maldistribution is determined by filtering and integrating the oxygen sensor signal, and the new offset value is determined by repeatedly incrementing the stored offset value, and fueling the individual cylinders of the engine based on the incremented offset value, until the measure of air-fuel ratio maldistribution decreases. In systems having a wide-range oxygen sensor, the measure of air / fuel ratio maldistribution is determined by summing the air / fuel ratio errors identified by the sensor, and the new offset value is determined by alternately toggling a selected cylinder rich and lean, and sampling the oxygen sensor signal to identify the selected cylinder. Either way, the control adapts the stored offset values for changes that occur over time due to component degradation and variation and changes in engine hardware.

An engine with inertial integration and delay is controlled through the use of a disturbance estimator. Control logic includes a feed-forward control path driving a control input with a control signal. The feed-forward control path is designed to provide closed-loop control of the controlled parameter without the presence of transport delay. The disturbance estimator generates an estimate of the engine disturbance. A Smith predictor generates a compensation signal for the feed-forward control path based on the control signal and the engine disturbance estimate.

In real-time critical wireless data applications, such as Push-to-talk over Cellular (PoC) or Push-To-Talk (PTT) and Voice-over-IP (VoIP), a user of a PTT mobile station pushes a button to indicate his desire to communicate with a pre-defined group (e.g., a buddy list) of people. This action triggers the PTT mobile station to re-activate a dormant data call connection and request the floor. When one or more of the mobile stations identified in the buddy list responds, a PTT server sends a Grant message to the PTT caller and he / she can start to talk. In one embodiment, the Grant message is sent to the PTT caller before the dormant call is completely reactivated to reduce PTT call setup latency.

In recent years, copper wiring has emerged as a promising substitute for the aluminum wiring in integrated circuits, because copper offers lower electrical resistance and better reliability at smaller dimensions than aluminum. However, use of copper typically requires forming a diffusion barrier to prevent contamination of other parts of an integrated circuit and forming a seed layer to facilitate copper plating steps. Unfortunately, conventional methods of forming the diffusion barriers and seed layers require use of separate wafer-processing chambers, giving rise to transport delays and the introduction of defect-causing particles. Accordingly, the inventors devised unique wafer-processing chambers and methods of forming barrier and seed layers. One embodiment of the wafer-processing chamber includes equipment for physical vapor deposition and equipment for chemical vapor deposition to facilitate formation of diffusion barriers and seed layers within one chamber, thereby promoting fabrication efficiency and reducing defects.

A method for stream synchronization of real-time multimedia transport over a packet network, in which the multimedia includes a first stream and a second stream which are buffered and played through buffers. The method includes: measuring average transport delays of the first and second streams; measuring transport delay jitters of the first and second streams; and calculating a delay difference between the first and second streams which corresponds to the average transport delays and the transport delay jitters of the first and second streams, and setting buffer durations. A device for stream synchronization of real-time multimedia transport over a packet network is also provided.

A Time Division Duplexed (TDD) digital distributed antenna system (DDAS) that performs simulcast distribution to multiple simulcast groups while using TDD time advanced burst to negate the data rate reducing effects of transport delays. The User Plane data is adapted for eliminating time delay ambiguities across multiple simulcast digital radios. In addition, the Control and Management Plane is aggregated across multiple remote units to allow a non-modified donor digital base station to control simulcast groups.

When transporting delay-sensitive traffics such as voice, video and radar data over Internet Protocol (IP), control of end-to-end delay becomes a challenge. Typical approaches tie up bandwidths for entire duration of call. Second thing they do, is prioritization of certain classes over others, to control queuing delays, but this prioritization, remains at class-level and does not go to individual session-levels. As a result certain sessions within a class get more delay than others. Depending upon situation, it can cause adverse effects to certain QoS sessions. In our invention we have developed an intelligent priority scheme which adapts serving priorities of sessions to control ETE delay of each individual QoS session. Priority adapting mechanism is based on feedback control which measures ETE delay of QoS session at destination node and broadcasts it to all nodes along the route of the session to adapt session's priorities to control ETE delay.

Methods and systems are provided for improving engine knock tolerance, in particular when rapidly ramping in LP-EGR from low levels of EGR. Until a desired LP-EGR rate is achieved, fuel may be delivered as a split injection with at least an intake stroke injection and a compression stroke injection to compensate for the transport delay in EGR filling the intake system. Subsequently, single fuel injection may be resumed.

A method for programming the delay for a node in a communication system is disclosed. The node receives a selected delay value and a signal path delay value indicating a delay for signals communicated to the node. The signal path delay comprises an aggregation of transport delays calculated by each node for segments of the communication system between the node and a host node. The method further calculates an additional delay necessary to meet the selected delay value.

An electronic control unit 50 determines whether the ambient air in the vicinity of an oxygen concentration sensor 55 in an exhaust passage 30 has become equal to the atmospheric state as a fuel cut-off operation is executed. If the ambient air in the vicinity of the oxygen concentration sensor 55 is equal to the atmospheric state, the electronic control unit 50 executes a learning process, in which a detection value C of the oxygen concentration sensor55 is stored as a learned value Cstd in a memory 56. The electronic control unit 50 continues the learning process until a predetermined time period set based on an exhaust gas transport delay elapses from when the fuel cut-off operation is terminated.

In one embodiment, an apparatus for providing a gas mixture of a plurality of gases, may have a plurality of mass flow controllers (MFCs), a mixing manifold in fluid connection with each plurality of MFCs, a plurality of mixing manifold exits positioned on the mixing manifold; and an isolation device in fluid connection with each of the plurality of mixing manifold exits.

In one embodiment, an apparatus for providing a gas mixture of a plurality of gases, may have a plurality of mass flow controllers (MFCs), a mixing manifold in fluid connection with each plurality of MFCs, a plurality of mixing manifold exits positioned on the mixing manifold; and an isolation device in fluid connection with each of the plurality of mixing manifold exits.

An embodiment of the disclosure provides a method and apparatus for reducing the delay in vehicle-to-vehicle communication. The method comprises the steps of allocating separate scheduling allocation resource pools for messages with different delay requirements; and performing frequency division multiplexing of a scheduling allocation resource pool for a first message requiring a lower delay and a corresponding data resource pool, to reduce the transmission delay of the first message. Compared with the prior art, the embodiment of the disclosure are effective in reducing the transmission delay of the emergency message, thus satisfying the delay requirements for vehicle safety message communication.

Methods and systems are provided for improving engine knock tolerance, in particular when rapidly ramping in LP-EGR from low levels of EGR. Until a desired LP-EGR rate is achieved, fuel may be delivered as a split injection with at least an intake stroke injection and a compression stroke injection to compensate for the transport delay in EGR filling the intake system. Subsequently, single fuel injection may be resumed.

A system includes a parameter generation system to determine at least one parameter for an injection procedure (for example, a parameter of an injection protocol or an imaging system parameter), the parameter generator system includes a physiologically based pharmacokinetic model to model propagation of a contrast medium injected into a patient including at least one of a non-linear saturation term in a peripheral venous compartment, at least one configurable transport delay term through at least one compartment, or an adaptation to model volumetric flow rate of blood and an effect thereof on the propagation of contrast medium after injection of contrast medium ceases. The physiologically based pharmacokinetic model can, for example, be discretizable.

A method and apparatus estimate hydrogen concentration in a reformate stream produced by a fuel processor of a fuel cell. A sensor measures carbon monoxide, carbon dioxide, and water in the reformate stream. A fuel meter controls fuel input to the fuel processor. An air meter controls air input to the fuel processor. A water meter controls water input to the fuel processor. A transport delay estimator recursively estimates transport delay of the fuel processor. A hydrogen estimator associated with the transport delay estimator, the air, water and fuel meters, and the sensor estimates hydrogen concentration in the reformate stream. The hydrogen estimator includes a fuel processor model that is adjusted using the estimated transport delay. The carbon monoxide, the carbon dioxide and the water are measured using a nondispersive infrared (NDIR) sensor.

The invention applies to servo controllers for at least the voice coil motor of a hard disk drive. Today, many control algorithms require 80 to 90 percent of the sampling period to complete their calculation of the next control, making computation time delay no longer negligible. The invention accommodates the transport delay, such as computation time delay, into the state estimator and into the whole control system. Experimental results using a commercial hard drive, as well as simulation results, show that the invention's method effectively improves the hard disk drive control system stability by increasing the phase margin and gain margin. The invention includes the method of operating the servo-controller, as well as the apparatus implementing that method. The invention also includes hard disk drives containing servo-controllers implementing the method, and program systems residing in accessibly coupled memory to a computer within the servo controller implementing the method.

The invention relates to a man-machine sharing steering control method of an intelligent automobile, aims to improve path tracking performance of the intelligent automobile and the operation comfort of a driver in a time delay communication environment, and belongs to the field of intelligent automobile driving auxiliary systems. The method comprises the following steps: establishing a pedestrian-automobile-road system model; determining a system control target; and solving the gain of the shared steering controller, calculating the required active steering angle, and carrying out the online control of the intelligent automobile. The automobile path tracking precision can be effectively improved, and the operation comfort of the driver can be increased. Particularly, a time delay phenomenon in a control loop is considered in man-machine sharing steering control of the intelligent automobile, and the delay comprises three types of network induction delay, signal transmission delay and actuator delay so that the path tracking performance of the automobile is ensured, and meanwhile, the robustness is relatively high, and the method has superiority in a time delay environment.

The invention discloses a multiprocessor shared storage method and system. The method comprises the steps: arranging at least one local interconnection network, wherein each local interconnection network is connected with at least two function modules; arranging local shared storage units connected with the local interconnection networks, and mapping the address space of the function modules on the local shared storage units; writing processed initial data into the local shared storage units through the local interconnection networks by the first function module of the at least two function modules; and obtaining data from the local shared storage units through the local interconnection networks by the second function module of the at least two function modules. According to the technical scheme disclosed by the invention, the defects that transport delay of the traditional multiprocessor global sharing storage system is large, managing expense is high and the like can be overcome.

The invention applies to servo controllers for at least the voice coil motor of a hard disk drive. Today, many control algorithms require 80 to 90 percent of the sampling period to complete their calculation of the next control, making computation time delay no longer negligible. The invention accommodates the transport delay, such as computation time delay, into the state estimator and into the whole control system. Experimental results using a commercial hard drive, as well as simulation results, show that the invention's method effectively improves the hard disk drive control system stability by increasing the phase margin and gain margin. The invention includes the method of operating the servo-controller, as well as the apparatus implementing that method. The invention also includes hard disk drives containing servo-controllers implementing the method, and program systems residing in accessibly coupled memory to a computer within the servo controller implementing the method.

The invention discloses a method of the boundary switch in multi-transport-type Code Division Multiple Access (CDMA) system, which comprises the following steps: when a mobile station detects that a pilot strength from the cell neighboring the mobile station cell is up to the soft handoff threshold, the mobile station reports a Pilot Strength Measurement Message containing the information of the neighboring cell to the base station. The base station obtains the attribute information of the mobile station cell and the neighboring cell from the mobile station. If both cells are of the same transport type, the mobile station is informed of an execution of the soft handoff. If not, the mobile station is informed of an execution of the hard handoff. The invention solves the problem of the failure of the soft handoff due to the different transport delay and achieves a high-quality switch of the mobile station in a mixed network consisting of cells of different transport type through the judgment of the cell transport attribute of the base station controller and the flexible adoption of the soft handoff process and the hard handoff process, which reduces the disconnection rate and improves the network quality and the user experience.

The invention discloses a field bus interface for a bus type detection element of a numerical control machine, which is used for communication between a position detection element on the numerical control machine and an external control module of the numerical control machine. The interface comprises a field programmable gate array (FPGA), an Ethernet physical layer (PHY) chip, a network transformer and a twisted pair joint, wherein the field programmable gate array (FPGA) is used for the transmission buffer and reception buffer of data, and protocol processing; the Ethernet physical layer (PHY) chip communicates with the field programmable gate array (FPGA), and is used for transmitting and receiving the data and converting differential analogue signals transmitted in a network into digital signals for the processing of the field programmable gate array (FPGA); the network transformer is connected with the Ethernet physical layer (PHY) chip, and is used for isolating the signals; and the twisted pair joint is connected with the network transformer, and is used for transmitting and receiving the analogue signals. The field bus interface can increase the communication rate of a bus to 100M and reduce transmission delay to be within one microsecond, and meets the requirements of high-speed and high-accuracy machining of the conventional numerical control machine.

The invention, which relates to the maglev train control technology, discloses a speed measuring and positioning method and system for a maglev train and the maglev train, and. According to the speedmeasuring and positioning method, on-board equipment acquires speed and position information of a first speed measurement system in a normal case; a ground traction control system acquires speed and position information of a second speed measurement system; the speed and position information of the first speed measurement system is directly transmitted to the on-board equipment and the speed and position information of the second speed measurement system is directly transmitted to the ground traction control system at the same time. Because of no transmission delay, the on-board equipment andthe ground traction control system synchronously receive the speed and position information of the train, so that the communication period is greatly shortened, the transmission delay of the speed andposition information is greatly shortened, and the reliability of the system is improved. The first speed measurement system and the second speed measurement system can operate independently and information interaction can be realized through the communication bus, so that cooperative work of the two speed measurement systems is realized and control over head-to-tail switching of trains is achieved.

An apparatus and method for detecting an abnormal air-fuel ratio variation between cylinders of a multi-cylinder internal combustion engine in which the output of an air-fuel ratio sensor is acquired at each sampling interval, a parameter correlated with the degree of fluctuation of the sensor output is calculated from a plurality of the acquired sensor outputs, and the presence or absence of the abnormal air-fuel ratio variation between cylinders is determined by comparing the parameter with a determination value. A cylinder air amount is estimated at each sampling interval. Every time the air-fuel ratio sensor output is acquired, the value of the cylinder air amount at the point earlier, by a transport delay time, than the point of the acquisition is determined based on the time-series data, and a corresponding determination value corresponding thereto is calculated. The determination value is determined based on a plurality of the calculated corresponding determination values.

A delay measurement circuit includes a transporting path selector, first and second delay measurement devices, and a controller. The delay measurement circuit forms a plurality of transporting loops through two of a first reference transporting conductive wire, a second reference transporting conductive wire, and a tested transporting conductive wire according to a control signal. The first delay measurement device respectively measures part of the transporting loops to obtain a plurality first transporting delays. The second delay measurement device respectively measures part of the transporting loops to obtain a plurality second transporting delays. The controller generates the control signal, and obtains a transporting delay of the tested transporting conductive wire according to the first transporting delays and the second transporting delays.

The invention relates to a thermoelectric cooperative regulation and control method and system based on heat supply network transmission time delay and heat storage characteristics. The thermoelectriccooperative regulation and control method comprises the steps of constructing a heat supply load change curve of each time sequence segment in a scheduling period; evaluating the transmission delay of the heat supply network; describing the maximum heat storage capacity of the generalized energy storage system according to the transmission delay of the heat supply network; establishing a heat storage and release scheme of the generalized energy storage system for the corresponding time sequence fragments according to the heat supply load change curve, and establishing constraint conditions; constructing a quality regulation delayed heat supply feasibility scheme solution set according to the maximum heat storage capacity and the like; constructing a real-time heat supply quantity adjustment feasibility scheme solution set corresponding to the quality adjustment delay heat supply feasibility scheme solution set; and establishing a target function according to the heat supply load change curve so as to obtain a thermoelectric cooperative regulation and control strategy in the current scheduling period, thereby effectively relieving the frequent and large-amplitude fluctuation operation state of the unit operation load caused by the change of the electric load demand and the insufficient heat supply caused by the limitation of the thermoelectric load production matching relationship of the unit.