135 results about "Threshold crossing" patented technology

A system and method for limiting the impact of an unstable wavelength on other wavelengths in a reconfigurable optical add / drop multiplexer (ROADM) network are disclosed. The method generally comprises measuring optical channel power at prescribed time intervals; for each measurement of channel power falling outside a predefined threshold, recording a threshold crossing event; comparing the recorded threshold crossing events to stored criteria indicative of an unstable wavelength channel; and removing an unstable wavelength from the ROADM network if the threshold crossing events exceed the stored criteria.

A controlling method for an electrical apparatus and a device thereof are provided in the present invention. The method includes the steps of: (a) providing an electrical apparatus and an AC power; (b) generating a control signal synchronized to the AC power; and (c) controlling the electrical apparatus by the control signal. The device includes a threshold detector, a phase-locked loop coupled to the threshold crossing detector and an output circuit coupled to the phase-locked loop.

The invention provides a distributed photovoltaic automatic generating control method based on sensitivity. The control method includes the following steps: a) solving the mathematical relation of the power distribution network node voltage disturbance amount and node injection active-reactive disturbance amount through the local linearization around the distribution network stable-state operation working points, namely, analyzing the variation relation of the node voltage amplitude and node active-reactive injection through a sensitivity analytical method; b) based on the sensitivity relation of the node voltage and the node injection, selecting a node having the highest voltage sensitivity of the node active-reactive injection to the node voltage threshold-crossing or widely fluctuating nodes in a distribution network as an active-reactive adjusting node to participate in the active-reactive optimization regulation, wherein a photovoltaic power generation system which doesn't participate in the adjustment always works at the largest power tracking state; and c) establishing a distributed photovoltaic optimization model by taking the distribution network distributed photovoltaic output maximization and node voltage rated value deviation minimization as the target and taking the active-reactive output value of the active-reactive adjusting node as a solving variable.

A system and automated method for assessing ventricular synchrony in ambulatory patients is provided including at least one mechanical sensor (e.g., accelerometer, tensiometric sensor, force transducer, and the like) operatively coupled to a first myocardial location in order to measure a wall motion signal of a first chamber, and a second mechanical sensor operatively coupled to a second myocardial location in order to measure a wall motion signal of a second chamber. The wall motion signals are processed in order to identify the time at which a fiducial (e.g., an inflection point, a threshold crossing, a maximum amplitude, etc.) occurs for each respective signal. The temporal separation between the fiducial points on each respective signal is measured as a metric of ventricular synchrony and can be optionally utilized to adjust pacing therapy timing to improve synchrony.

Systems and methods for an integrated approach lighting system are described. An integrated approach lighting system includes a threshold bar and a plurality of lighting towers. The systems and methods provide advantages in that pilots are given a precise three dimensional visual reference to the aircraft's position relative to the runway's centerline, threshold crossing and height above the airfield. This provides the pilot with a higher concentration of visual information to insure faster decision making and an easier, more accurate and safe approach to landing.

The invention relates to a cascading failure search and weak link analysis method based on an operation reliability model. The method comprises steps: initial failure is generated randomly; a DC power flow is calculated, whether a load threshold-crossing line exists in a power system is judged, if yes, a next step is carried out, or otherwise, the operation is stopped; an initial failure set is generated, and through the operation reliability model, the threshold-crossing line outage probability is calculated; the power system state probability is calculated; if the power state probability is larger than a set threshold and the failure scale is smaller than a set threshold, the power state is added to an alternative failure set, and if no state meeting the condition exists, search is stopped; the initial failure set is taken as an alternative failure set, the current alternative failure set is emptied, and the above steps are repeated. Through searching a cascading failure event in different initial failure and analyzing a system weak link, a corresponding system reform scheme is provided, happening of the cascading failure is prevented, a subsequent event is found during an event development process, and further evolution of the cascading event can be prevented.

The invention relates to an AC power flow constraint-based uncertainty unit commitment model and a solving method. With the minimum fuel cost sum for a thermal power unit in 24 hours as an optimization target, a chance-constrained method is adopted to describe uncertainty for wind power output, AC power flow model-based network security constraints are built, and thus, the AC power flow security constraint-based uncertainty unit commitment model is provided. In view of the problem that the model is hard to solve, the invention provides a random constraint ordinal optimization method for successfully realizing quick model solution. In comparison with the traditional DC power flow constraint-based uncertainty unit commitment model, the provided model of the invention can effectively reduce the risk of threshold crossing of power grid voltage after large-scale wind power access, effectiveness of current power generation planning decisions is enhanced, the built model can finely calculate system network losses, and data reference is provided for a dispatching person. In addition, the solved algorithm is greatly enhanced compared with the traditional algorithm.

The invention relates to a meteorologic signal processing IP core of low-altitude monitoring radar and a real-time data sorting method of the meteorologic signal processing IP core. The IP core comprises a digital intermediate frequency phase demodulation module, a pulse compression module, a data rearrangement module, a time domain windowing and FFT module, a noise power estimation module, a point clutter suppression module, an autocorrelation parameter estimation module, a distance averaging module, a distance and intensity correction module and a threshold crossing processing module. The meteorologic signal processing IP core of the low-altitude monitoring radar has the advantages of being simple in structure, high in real-time processing capacity and reliability and the like, target detection and meteorologic detection in the low-altitude monitoring radar are made compatible with each other, and the IP core further has the advantages that the number of system elements is reduced, and integration degree and stability of the system are improved. Through the real-time data sorting method, the complexity of data sorting in space and time can be greatly reduced, and the real-time data sorting method is high in reliability and real time performance and provides a guarantee for precise estimation of noise power.

A control system for determining a magnitude of a voltage and controlling an application of the voltage to at least one load device of an appliance is disclosed. The control system includes a threshold-crossing circuit configured to receive a representation of the voltage and to provide an output signifying the voltage crossing a predetermined voltage threshold; and a processor which receives the output from the threshold-crossing circuit and determine the magnitude of the voltage based on the output and a line frequency based on the period of the output, determines an initial cooking profile from a group of cooking profiles based on a user selected initial setting for controlling the application of the voltage to the at least one load device, and adjusts the application of the voltage to the at least one load device based on the determined magnitude of the voltage.

The invention provides a time synchronization monitoring method and system. The method includes sending monitoring information to a master-station time synchronization device through a precision clock protocol channel after a slave-station time synchronization device receives time service information sent by the master-station time synchronization device through the precision clock protocol channel and when the time service information is verified to pass; detecting the monitoring information according to local time information of a master station by the master-station time synchronization device to acquire a detecting result; sending time deviation in the detecting result to the slave-station time synchronization device through the precision clock protocol channel to perform time adjustment; uploading the detecting result to a background of the time synchronization monitoring system to perform storage, statistical analysis or threshold crossing alarm. By the time synchronization monitoring method and system, monitoring on time synchronization through a time service channel is realized, the problem that channels are only occupied by data channels in conventional technology is solved, and utilization rate of channel resources is increased.

The invention provides a method for implementation of micro-grid probability load flow analysis. The method includes the steps: numbering each node in a micro-grid, and forming a node admittance matrix according to micro-grid system data; working out semi-invariants of each stage of injection power according to probability distribution of each node injection power; aiming at uncertainty node injection powers, using the statistic method to obtain a mean value of micro-grid load flow and obtain a Jacobi matrix mean value of the last iteration; obtaining semi-invariants of each stage of system state variables according to the semi-invariants of each stage of each node injection power and the Jacobi matrix mean value of the last iteration; working out each coefficient of Gram-Charlier stages corresponding to a probability distribution function according to the semi-invariants of each stage of system state variables; approximately representing state variable probability distribution by means of Gram-Charlier stage truncation, and working out probability of events such as threshold crossing. Micro-grid probability load flow solution is realized by means of the conception of probability and mathematical statistics of the semi-invariants and the Gram-Charlier stages, uncertainty can be reflected, and micro-grid planning and evaluation on the micro-grid by operators can be facilitated.

A self-adjusting hold-off trigger circuit and method detects a threshold crossing between consecutive samples of a digitized input signal as edge events, identifies the crossing as a qualified trigger event if the crossing is in a desired direction based upon trigger criteria, and provides a trigger output when the qualified trigger event occurs greater than an approximate average or peak time after a preceding edge event.

An apparatus and method for monitoring a computer system operable for alerting an operator to failures associated with critical resource consumption and comprises: a resource monitoring component for monitoring resource consumption; a threshold setting component for setting a threshold of resource consumption between an average resource consumption value and a critical resource consumption value; a diagnostic data collection component; and a threshold crossing detection component; wherein the diagnostic data collection component is operable, in response to the threshold crossing detection component detecting a threshold crossing, to start or stop diagnostic data collection.

A system and method are provided for monitoring utilization of network resources in a photonic network. A monitoring threshold is set for monitoring utilization of network components of interest. A resource utilization data processor obtains resource utilization data indicating utilization of the network resources. A threshold crossing determination unit determines if threshold crossing has occurred based on the utilization data and the monitoring threshold. A user interface indicates the utilization of the network components in accordance with the determination of the threshold crossing.

The invention relates to a prevention, control and fault handling method and system for a power distribution network. The prevention, control and fault handling system for the power distribution network comprises a uniform-control platform, an information acquisition unit and a prevention and control unit, wherein one end of the uniform-control platform is connected with the information acquisition unit, the other end of the uniform-control platform is connected with the prevention and control unit, the prevention and control unit is used for predicting the abnormal operating state of devices in the power distribution network in a short period of time in future, and the prevention and control unit comprises a second index calculation module used for setting an index in advance according to the information of the devices in the power distribution network and the information of a network topology and storing the information of the topology so that data support can be provided for a fault handling unit. The prevention, control and fault handling method and system for the power distribution network have the advantages that the practicability is high, threshold crossing can not occur easily in a short period of time, time of prevention and control handing is effectively saved, energy is saved, and the probability of occurrence of faults is lowered.

The invention relates to a security risk assessment method of a wind-power-included electric power system based on Gaussian mixture distribution characteristics. The security risk assessment method comprises the following steps: counting up the distribution of historical data of output power of a wind power plant; establishing a non-parameter probability distribution model of the output power of the wind power plant; establishing a Gaussian mixture distribution model of the output power of the wind power plant; determining the quantity of Gaussian distribution and initializing parameters of each Gaussian distribution; solving the parameters of each Gaussian distribution and determining the Gaussian mixture distribution characteristics; determining cumulative distribution functions of state variable node voltage and branch power flow; and calculating state variable threshold-crossing probability and severity of generated results, and comprehensively estimating safety risks of the electric power system. According to the security risk assessment method provided by the invention, a semi-invariant solving process of node injection power of the system is greatly simplified, so that the efficiency of semi-invariant calculation of the node injection power and the accuracy of the cumulative distribution functions of state variable node voltage and the branch power flow are improved, and thus effective data supports are provided for security risk assessment of the electric power system.

Disclosed is a system for improving local electric network power supply ability analysis and providing entire process online monitoring. The system comprises a sub-system receiving original power data in targeted areas, wherein the sub-system classifies the original power data according to node data, line data and transformer data; a sub-system computing power supply capability according to power data, wherein the sub-system uses the improved trial-and-error method based on repeated trends to compute the power supply capability of the local electric network. The computing process comprises that a critical point is obtained under a predetermined operation mode and a load growth mode, a limited condition exactly at the critical point is effective, a threshold crossing occurs when load increases over the critical point, the critical point corresponds to the maximum power supply capability of the local electric network, and the available power supply capability is the difference between the maximum power supply capability and the present interlocal transmission load. The system also comprises an aid decision-making sub-system evaluating the power supply capability of the targeted areas according to computed results, wherein the sub-system provides detailed parameters of weak devices with threshold crossing priority in operation, thereby performing an alarm mechanism.

The invention provides a joint detection and tracking method for a sea target by using a two-coordinate radar. The method includes: performing background self-adaptive threshold detection on originalvideo data, and initially eliminating the clutter and noise; extracting trace point information according to the order of distance first and position second, secondly eliminating threshold-crossing echoes that do not satisfy the aggregation criterion, and calculating the track point quality according to the distance azimuth two-dimensional echo characteristics of the condensed track points; usingthe dynamic hypothesis path search and the track point quality as a reference to define a search path cost function, and forming a dynamic hypothetical track cluster; and finally using the multi-cyclecost function accumulation result to perform detection decision and track optimization and merging to achieve joint detection and tracking of the target.

Methods, computer program products, and systems for managing VoIP network elements are provided. Methods include receiving call details records (CDRs) from a plurality of network elements. The received CDRs including disconnect cause codes and telephone call correlation identifiers. The received CDRs are correlated to telephone calls based on the telephone call correlation identifiers. Two CDR records are associated with the same telephone call when their telephone call correlation identifiers are the same. A master correlated CDR is created for each telephone call. The creating includes assigning a correlated disconnect cause code and classifying the telephone call. The assigning and classifying are responsive to the received CDRs associated with the telephone call. The master correlated CDR includes the correlated disconnect cause code and the telephone call classification. A threshold crossing alert (TCA) is generated in response to a threshold for the correlated disconnect cause code being reached.

The invention relates to a multi-fault coordinated static security comprehensive aid decision making method. The method includes the following steps that: the calculation result of static security analysis is read; sensitivity analysis is performed on threshold-crossing devices and failure devices; the adjustment directions of adjustable devices, which are required by the threshold-crossing devices, are determined according to the sensitivity relationship between the threshold-crossing devices and the adjustable devices; if a plurality of devices cross thresholds, whether the adjustment directions of the adjustable devices for the threshold-crossing devices conflict with each other is judged; if the adjustable devices for the threshold-crossing devices do not conflict with each other, the method enters the next step; if the adjustment directions of the adjustable devices for the threshold-crossing devices conflict with each other, an adjustability adequacy indicator is calculated, the adjustment directions of adjustable devices which conflict with each other are determined according to the adjustability adequacy; and multi-fault coordinated static security comprehensive aid decision making is solved. The method provided by the technical schemes of the invention is easy to implement, and a coordination optimization problem which appears when the adjustment requirements of multi-fault static security threshold crossing for the adjustable devices conflict with each other can be solved, and a comprehensive aid decision-making adjustment strategy can be automatically given.

The invention relates to a method for the comprehensive control of passive filter and reactive power compensation, which comprises: firstly, judging locking conditions including total distortion and default phase of a harmonic current and voltage threshold crossing, and locking a feed outlet and switching to a protective flow when any condition is met; and when no locking condition is met, entering a control policy selection flow, wherein the policy selection is performed mainly for judging if a potential maximum subharmonic exceeds a standard, switching is performed according to a reactive power compensation policy if the potential maximum subharmonic does not exceed the standard, and control is performed according to a filter wave if the potential maximum subharmonic exceeds the standard. In the invention, through the dual control of the reactive power compensation and the filter, a power system can output at a maximum power and the production benefits are increased; and a locking protection function is provided, so the safe and reliable operation of the system are further ensured.

The invention puts forward an alternating current-direct current active electric power distribution network voltage and reactive power coordinated control method comprising the following steps: electric power distribution network voltage running states are segmented into three bands that are respectively a normal state, an early warning and an emergency state according to node voltage levels of an electric power distribution network; in the normal state, global optimization operation is perform, dynamic reactive power of a flexible direct current device is replaced with static state reactive power of a discrete reactive power device, and a dynamic reactive reserve capacity of the electric power distribution network can be improved; in the early warning state, intercoordination of local control and centralized control is realized via multiple reactive power sources, and voltage threshold-crossing nodes can be corrected in the early warning state; in the emergency state, the flexible direct current device is used for providing emergency support to the voltage threshold-crossing nodes, and the electric power distribution network is enabled to transit to the early warning state till the electric power distribution network goes back to the normal state.

A system including a turbine including a compressor having at least one row of a plurality of blades; a sensor for sensing a blade passing signal of at least one of the plurality of blades; an analog signal transmitter for transmitting an analog signal for the blade passing signal; a signal splitter for splitting the analog signal into at least two split analog signals; at least two analog-to-digital (AD) converters, each AD converter converting each split analog signal to at least two digital waveform samples; and a blade monitoring system that: calculates at least two interpolated threshold crossings, each interpolated threshold crossing calculated from at least two digital waveform samples from each AD converter; and calculates an average threshold crossing (ATC) of the at least two interpolated threshold crossings.