134 results about "Threshold crossing" patented technology

A system and method of implementing precision time delays that provides important and novel improvements over prior techniques of implementing time delays by utilizing a new strategy for selecting the values in the sine and cosine lookup tables. Sine and cosine values which result in non-uniform amplitudes enable increased overall accuracy with fewer bits communicated from the look-up tables to the analogue portion of the system. Further, herein is provided the addition of a variable amplitude threshold crossing capability following the combining of the sine and cosine signals. The time delay accuracy of the resulting phase and amplitude hybrid system can be improved either by increasing the number of bits in the sine / cosine phase management section or by increasing the number of bits in the amplitude section. There is provided herein an optimum strategy for choosing the number of bits used in the phase and amplitude sections for the best overall delay accuracy with the fewest overall control bits.

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.

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.

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.

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 discloses a wind power bundling control method after wind power and thermal power accessing to a power grid and belongs to the technical field of power system security defense. The method includes: forwardly or reversely adjusting wind power and thermal power output; respectively calculating and power grid transient stability margin, element load degree index and bus voltage threshold-crossing index after wind power and thermal power output adjustment; calculating wind power / thermal power output according to the calculated power grid transient stability margin, element load degree index and bus voltage threshold-crossing index; reversely / forwardly adjusting wind power and thermal power output when wind power / thermal power output is larger than a preset threshold; and forwardly / reversely adjusting wind power and thermal power output when wind power / thermal power output is smaller than the preset threshold. By the method, reasonable wind power and thermal power output is guaranteed, and normal operation of the power grid is guaranteed.

Circuitry adapted for carrying out associated techniques for: (a) calculating a damping factor, e.g., a damping ratio represented by ζ, or a quality factor Q, where ζ≈1 / 2Q, for a transient signal received, having been emitted from a resonator-type sensor element; (b) determining amplitude, A, of the transient signal; or (c) generating a frequency response dataset of interrelated points for the transient signal. A threshold comparison circuit is included for converting the transient signal received into a first and second digital waveform; the first digital waveform represents cycle crossings of the transient signal associated with a first threshold value, and the second digital waveform represents cycle crossings of the transient signal associated with a second threshold value. The transient signal may be converted, likewise, into third, and so on, digital waveforms, whereby the third digital waveform represents cycle crossings of the transient signal associated with a third threshold value. Respective digital counters are included, each of which is adapted for determining a total number of cycles of the first, second, third, and so on, digital waveform. A processing unit of suitable speed and capacity is employed for the calculating of the damping factor, determining an amplitude, and / or generating a frequency response dataset.

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.

A description of signal behavior in the vicinity of a time and voltage of interest is produced by defining a region in the (time, voltage) plane that is a closed straight sided figure whose vertices are identified by threshold crossings offset for the voltage of interest and clocked by time delays offset from a clock time of interest. A first set of latches clocked by the time delays accumulates the state of signal behavior relative to the threshold voltages as it occurs, and their contents are subsequently transferred to a second set of latches at the start of a new clock cycle, allowing a new accumulation to begin and also allowing a detection logic circuit to operate on a unified and completed collection of indicators of what the just concluded description amounts to. The detection logic circuit responds to the combinations of latched indications to produce a signal corresponding to that description. The closed figure need not be a rectangle, and it may also serve as an indication that a signal went into a region that it should not have, e.g., an eye violation detector.

In many situations, it is desirable to restrict access to digital content. This invention presents an extremely efficient and simple method and apparatus to degrade and recover digital content. The invented process is based upon searching the data for detection criteria and then adjusting neighboring point(s) to degrade the content, or re-adjusting the neighboring point(s) to recover the original content. For example, one could search for threshold crossings, and scale the following point by a number between 0 and 1 for degradation, or re-scale the following point by the inverse scaling value to recover the original data. The apparatus may include a logic processor and storage unit to implement the degradation and recovery process.

A method and apparatus for pulse pile-up rejection are disclosed. The apparatus comprises a delay value application constituent configured to receive a threshold-crossing time value, and provide an adjustable value according to a delay value and the threshold-crossing time value; and a comparison constituent configured to receive a peak-occurrence time value and the adjustable value, compare the peak-occurrence time value with the adjustable value, indicate pulse acceptance if the peak-occurrence time value is less than or equal to the adjustable value, and indicate pulse rejection if the peak-occurrence time value is greater than the adjustable value.