21186 results about "Peak value" patented technology

An electrosurgical generator for supplying RF power to an electrosurgical instrument for cutting or vaporising tissue has an RF output stage (42) with an RF power bridge (Q1, Q2, Q3, Q4), a pair of output lines (74) and a series-resonant output network (48). The output impedance of the output stage (42) at the output lines (74) is less than 200 / √P ohms, where P is the maximum continuous RF output power of the generator. The generator offers improved cutting and vaporising performance, especially in relation to the reliability with which an arc can be struck when presented with an initial low impedance load. Overloading of the output stage is prevented by rapidly operating protection circuitry responsive to a predetermined electrical condition such as a substantial short-circuit across the output lines. In the preferred embodiment, the output stage is capable of maintaining output pulses at least 1kW peak by supplying the power bridge from a large reservoir capacitor (60). Pulsing is dynamically variable in response to load conditions by controlling the maximum energy per pulse in response to the reservoir capacitor voltage.

An electrically operated, directly overwritable, multibit, single-cell chalcogenide memory element with multibit storage capabilities and having at least one contact for supplying electrical input signals to set the memory element to a selected resistance value, the second contact tapering to a peak adjacent to the memory element. In this manner the tapered contact helps define the size and position of a conduction path through the memory element.

In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. For example, the loading conditions of the cells can be detected, and the resources can be reallocated and / or the reuse scheme can be redefined. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users. Data transmissions can be scheduled based on user priorities, some fairness criteria, system requirements, and other factors. Users are assigned to available channels based on a number of channel assignment schemes. Channel metrics are also provided, which can be used to prioritize users and for channel assignments.

The LED brightness control system for a wide range of luminance control includes a brightness control module that provides a pulse width modulation (PWM) control signal and a peak current control signal. A pulse width modulation (PWM) converter circuit receives the PWM control signal and converts it to a PWM signal. A multiplier receives the PWM signal and the peak current control signal from the brightness control module and multiplies the same to provide a light emitting diode (LED) current control signal with a variable “on” time as well as variable “on” level. A voltage-controlled current source utilizes the LED current control signal and an LED current feedback signal for providing an LED current. An LED illuminator array receives the LED current. A current sensing element connected to the LED illuminator array for providing an LED current feedback signal representing LED peak current. The voltage-controlled current source controls a drive voltage to the LED illuminator array at a commanded level.

MRI / RF compatible leads include at least one conductor, a respective conductor having at least one segment with a multi-layer stacked coil configuration. The lead can be configured so that the lead heats local tissue less than about 10 degrees Celsius (typically about 5 degrees Celsius or less) or does not heat local tissue when a patient is exposed to target RF frequencies at a peak input SAR of at least about 4 W / kg and / or a whole body average SAR of at least about 2 W / kg. Related leads and methods of fabricating leads are also described.

A control unit is attached to or embedded within a refrigeration appliance to monitor electric power voltage and / or frequency supplied by the mains. If the unit detects a sag or peak in either the voltage or frequency, the control unit either separates any high demand elements of the appliance from the mains to reduce demand in a sag or energizes the elements in a peak. When the control system separates the refrigeration compressor from the mains, a food spoilage monitoring system monitors the food storage compartments. This system utilizes food industry temperature and time algorithms to ensure the food does not spoil. If food spoilage could occur, the unit re-energizes the compressor to allow it to lower the temperature provided the power is sufficient to operate the compressor unit without damaging it. Once the sensed temperature is restored to a safe level, the unit separates the compressor from the mains.

The invention is directed to techniques for selecting a resource from several resources to process a request from a client. A client sends the request to a data communications device (e.g., network device or switch), which measures usage information from usage meters associated with each resource (e.g., server). The data communications device then makes a usage estimate for each server of the increase in usage required for that server to process the request from the client. Then the data communications device selects one of the servers depending on the usage estimates required to respond to the client's request. The data communications device can consider other factors such as the current level of usage, past usage, and the increased cost of responding to the request. In addition, the data communications device can consider the peak usage level of each resource already established in a current billing period.

A UV irradiation apparatus for processing a semiconductor substrate includes: a UV lamp unit having at least one dielectric barrier discharge excimer lamp which is constituted by a luminous tube containing a rare gas wherein an inner surface of the luminous tube is coated with a fluorescent substance having a peak emission spectrum in a wavelength range of 190 nm to 350 nm; and a reaction chamber disposed under the UV lamp unit and connected thereto via a transmission window.

A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Modularity is ensured by the implementation of interchangeable amplifier components. System compactness is ensured by employing efficient fiber amplifiers, directly or indirectly pumped by diode lasers. Peak power handling capability of the fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. After amplification, the dispersively stretched pulses can be re-compressed to nearly their bandwidth limit by the implementation of another set of dispersive delay lines. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of the ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used.

Streaming video data from the video title is delivered to a client from a central server and a proxy server. To reduce the backbone bandwidth required, a portion of the video title is cached at the proxy server where the portion cached is distributed over the video title so as to reduce the peak bit rate required for the central server to send the remaining portion of the video title. The amount cached at the proxy server may be adjusted in accordance with access profile of video titles to improve caching efficiency. The portion cached may be the basic layer in a scalable multilayer approach where only the basic layer may be sent to a client who has limited bandwidth while clients with higher bandwidth capability may also receive the enhancement layer(s) for improved video reception.

A light emitting diode (LED) lighting system includes a power factor correction (PFC) controller that determines at least one power factor correction control parameter from phase delays of a phase modulated signal. In at least one embodiment, a peak voltage of the phase modulated signal is a PFC control parameter used bit the PFC controller to control power factor correction and generation of a link voltage by a PFC LED driver circuit. The phase delays are related to a peak voltage of the phase modulated signal. Thus, in at least one embodiment, detecting the phase delay in one or more cycles of the phase modulated signal allows the PFC controller to determine the peak voltage of the phase modulated signal.

Methods and apparatus for storing data records associated with an extreme value are disclosed. Signal data is stored in a first buffer of a set of buffers. If a local extreme value for the first buffer exceeds a global extreme value, signal data is stored in a second buffer of the set of buffers. This process is repeated, wrapping around and overwriting buffers until the signal data in a current buffer does not have a local extreme value that exceeds the global extreme value. When this happens, signal data may be stored in a subsequent buffer and if a local extreme value of the subsequent buffer does not exceed the global extreme value, further signal data may be stored in the subsequent buffer in a circular manner until either an instantaneous extreme value exceeds the global extreme value or the recording period ends. In an embodiment, the extreme value may be a peak value.

The present invention provides a preamble that is inserted into an OFDMA frame and has a common sequence for all the base stations participating in a transmission. The subscriber station performs fine synchronization using the common sequence on the common preamble, and the resulting peaks will provide the locations of candidate base stations. The base station specific search is then performed in the vicinities of those peaks by using base station specific pseudo-noise sequences. With this two stage cell search, the searching window is drastically reduced. The preamble is matched to known values by a respective receiver to decode the signals and permit multiple signals to be transferred from the transmitter to the receiver. The preamble may comprise two parts, Preamble-1 and Preamble-2, which may be used in different systems, including multioutput, multi-input (MIMO) systems.

The Electric Power Converter has the qualifications for an uninterruptable power supply, battery management, energy conversion, micro-grid formation, Power Factor Correction including Total Harmonic Distortion correction in real time. Uninterruptable power supply's use is for always-on, real-time, all-time, reduced distortion with functions of load reduction and management during peak load events. The Electric Power Converter as well has the ability to provide maintenance for most types of batteries including charging and discharge regiments to increase the overall lifetime of a battery, the maintenance, incorporating restorative functions that can refurbish dead batteries or can further increase the overall efficiency and useful function of weaker / aged / defective batteries. Energy conversion capabilities allow for the conversion of AC or DC to AC or DC with high efficiency and ability to actively vary the frequency in accordance to the required parameters. The Electric Power Converter is able to establish and sustain a micro-grid with multiple and varying sources of power generation and load conditions. The Electric Power Converter is achieving dynamic, real-time, interactive Power Factor Correction (PFC) function with advanced voltage harmonic distortion correction with a high efficiency ratio. The Electric Power converter is designed to function with the emerging Smart Grid technologies and provide an overall higher level of operating efficiency and higher quality of electrical power.

In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users.

A driving method and a driving device are provided for an LED element in which light emitting layers different from each other in light emission wavelength peak, put on each other with a barrier layer being interposed, are sandwiched by a pair of p-type and n-type layers, and color of emitted light from which substantially depends only upon driving current value. The method comprises a driving current value calculation step of obtaining a value for designating a current value corresponding to a desired color of emitted light from the LED element; a driving current generation step of generating a driving current having the current value designated by the value obtained in the driving current value calculation step; and a driving current supply step of supplying the LED element with the driving current generated in the driving current generation step.

A system and method for monitoring left ventricular cardiac contractility and for optimizing a cardiac therapy based on left ventricular lateral wall acceleration (LVA) are provided. The system includes an implantable or external cardiac stimulation device in association with a set of leads including a left ventricular epicardial or coronary sinus lead equipped with an acceleration sensor. The device receives and processes acceleration sensor signals to determine a signal characteristic indicative of LVA during isovolumic contraction. A therapy optimization method evaluates the LVA during varying therapy settings and selects the setting(s) that correspond to a maximum LVA during isovolumic contraction. In one embodiment, the optimal inter-ventricular pacing interval for use in cardiac resynchronization therapy is determined as the interval corresponding to the highest amplitude of the first LVA peak during isovolumic contraction.

A system and method are provided for smoothing the in-room acoustic magnitude response of an audio reproduction system. An in-room acoustic magnitude response analysis is performed to determine a room resonance induced peak associated with an audio signal. A replica of the audio signal is filtered at the room resonance induced peak. The filtered replica signal is added with the audio signal. Through this, smoothing of the room resonance induced peak may be achieved, such that a subjective impression of transient response and dynamics of the audio signal are preserved.

A method for recharging an electric storage battery in the charging system of an electric vehicle from an electric utility power grid includes determining the length of time required to recharge the battery, determining the desired time when the recharge is to be completed, transmitting to the electric power utility the length of time required to recharge the battery and the desired time, and recharging the battery from the utility grid during a period when projected load demand is lower than peak demand and ending no later than the desired time.

Methods for determining a mechanical parameter of a sample include detecting shear waves that have been generated in the sample by an applied shear wave source. A time of peak displacement of the shear waves for a plurality of sample positions is determined. At least one mechanical parameter of the sample based on the time of peak displacement for the plurality of sample positions is determined.

Provided are an envelope processor 103, for obtaining an envelope for a detected signal; a FFT unit 104, for converting the envelope into a frequency spectrum; a peak detector 105, for smoothing the frequency spectrum by calculating a moving average, for further performing smoothing and differentiation for the spectrum, and detecting, as peaks, frequency points at which a sign of a differential coefficient is changed from positive to negative, for extracting peaks having a predetermined threshold value or greater, and for sorting the extracted peaks and detecting upper peaks; and a diagnosis processor T, for diagnosing an abnormality based on the detected peaks.

The disclosure relates to General Synchronized Vibration devices that provide haptic feedback to a user and improve the performance of existing vibratory devices. Different actuator types may be employed to provide synchronized vibration, including linear rotary actuators, rotating eccentric mass actuators including interleaved rotating mass actuators, and rocking mass actuators. A controller sends signals to one or more driver circuits to provide adjustment of vibration magnitude, frequency, and direction of the actuators. The system may apply forces onto an object, and a sensor measures a feature(s) of the object. This information is provided to a vibration device controller, which can then modify the vibration waveform to improve overall system performance. Fourier synthesis can be used to approximate arbitrarily shaped waveforms by controlling the phase and frequency of vibration actuators. These waveforms can include asymmetry where the peak force in one direction is higher than the peak force in another direction.

An autofocus searching method includes the following procedures. First, focus values of images, which are acquired during the movement of the object lens, are calculated, in which the focus value includes at least the intensity value of the image derived from the intensities of the pixels of the image. Next, focus searching is based on a first focus-searching step constant and a first focus-searching direction, in which the first focus-searching step constant is a function, e.g., the multiplication, of the focus value and a focus-searching step. If the focus searching position moves across a peak of the focus values, it is then amended to be based on a second focus-searching direction and a second focus-searching step constant, in which the second focus-searching step constant is smaller than the first focus-searching step constant, and the second focus-searching direction is opposite to the first focus-searching direction.

The present invention relates to regulated power supplies or ballasts integrated with an LED light source. The invention provides a power factor correction scheme producing a greater circuit power factor and improved frequency spectrum characteristics, in which a voltage corresponding to the instantaneous inductor current is sampled and compared to a scaled sample of the rectified input AC line voltage. The line voltage sample modulates the inductor peak charge current in the envelope of the rectified AC voltage waveform. This drives the LED output voltage at a frequency of twice the input line voltage frequency, such that no flicker is perceived in the light output because the persistence in LED phosphor assists in averaging the flux output.

A MPPT management method in a receiver used for wireless power transmission may include the monitoring of the power extracted from RF waves at a dedicated antenna element in the receiver; detecting MPPT at an intelligent input boost converter in the receiver; comparing the detected MPPT with MPPT tables stored or calculated within a main system micro-controller in the receiver; adjusting the MPPT at the intelligent boost converter to find a suitable maximum peak that may enable an optimal power extraction from RF waves.