1820 results about "Correlation function" patented technology

A system and method for imaging a sample are provided. In particular, a first combination of light and a second combination of light are received, in which a first cross correlation function is associated with the first combination and a second cross correlation function is associated with the second combination. Each of the first and the second combinations includes a first portion of light which is received from a reference arrangement and a second portion of light which is received from the sample, and a first relative position of the sample associated with the first combination is different than a second relative position of the sample associated with the second combination. In an exemplary embodiment of the present invention, the first cross correlation function is transformed into a first complex cross spectral density and the second cross correlation function is transformed into a second complex cross spectral density. Moreover, a third complex cross spectral density can be determined which is approximately an average of the first complex cross spectral density and the second complex cross spectral density.

A system and method for imaging a sample are provided. In particular, a first combination of light and a second combination of light are received, in which a first cross correlation function is associated with the first combination and a second cross correlation function is associated with the second combination. Each of the first and the second combinations includes a first portion of light which is received from a reference arrangement and a second portion of light which is received from the sample, and a first relative position of the sample associated with the first combination is different than a second relative position of the sample associated with the second combination. In an exemplary embodiment of the present invention, the first cross correlation function is transformed into a first complex cross spectral density and the second cross correlation function is transformed into a second complex cross spectral density. Moreover, a third complex cross spectral density can be determined which is approximately an average of the first complex cross spectral density and the second complex cross spectral density.

Apparatus (15, 30) and methods for performing acoustical measurements are provided having some and preferably all of the following features: (A) the system (15, 30) is operated under near-field conditions; (B) the piezoelement (40) or piezoelements (40, 48) used in the system are (i) mechanically (41, 49) and electrically (13, 16) damped and (ii) efficiently electrically coupled to the signal processing components of the system; (C) each piezoelement (40, 48) used in the system includes an acoustical transformer (42, 50) for coupling the element to a gaseous test medium (9); (D) speed of sound is determined from the time difference between two detections of an acoustical pulse (81, 82) at a receiver (40, FIG. 3; 48, FIG. 7); (E) cross-correlation techniques are employed to detect the acoustical pulse at the receiver; (F) forward and inverse Fourier transforms employing fast Fourier transform techniques are used to implement the cross-correlation techniques; in such a mathematical manner that the peak of the cross-correlation function corresponds to the detection of a pulse at the receiver and (G) stray path signals through the body (31) of the acoustic sensor (15, 30) are removed from detected signals prior to signal analysis. Techniques are also provided for performing acoustical measurements on gases whose thermodynamic properties have not been measured and on mixtures of compressible gases. Methods and apparatus (29) for performing feedback control of a gas of interest in a mixture of that gas and a carrier gas are provided in which the controlled variable is the flow of the carrier gas.

An electronic image stabilizer in a digital camera compensates for camera motion-induced blurriness by segmenting exposure times into multiple shorter exposure times and summing the individual pixels from successive frames after applying an appropriate motion correction. Motion is detected by computing the correlation function between successive images, and compensation is applied by maximizing the correlation function. This avoids the need for mechanical stabilization devices in order to detect or correct the motion as is done in prior art. This method further enables the detection of moving objects in a still background, and correction of blurriness images due to such motion.

The invention discloses a distribution network line fault section positioning method based on full-waveform information. For the grounding fault, line selection is carried out through extreme value points of a cross-correlation function of the bus zero-sequence voltage and all outgoing line zero-sequence currents, and positioning is carried out according to the adjacent detection point zero-sequence current waveform standard drift rate of the whole action process of a fault occurrence and compensation device; for the interphase fault, line selection is carried out according to the overcurrent information obtained before action of a relay protection device, and positioning is carried out according to the adjacent detection point fault phase current waveform standard drift rate. The waveform data of the whole action process of a fault and arc extinction device are utilized, the current ubiquitous problems that when a small current grounding system encounters the single-phase grounding phase, the fault current is weak, the reliability is poor, and the sensitivity is low can be well solved, and meanwhile the system cannot get interference.

A system and method are provided for significantly reducing or substantially eliminating angular geometric distortions in devices designed for imaging and / or inspection of an interior portion or surface of a cavity. A series of processing steps or methods may be employed to eliminate Non-Uniform Rotational Distortion (NURD) in such devices, for example, unidirectional and bi-directional intravascular ultrasonic (IVUS) imaging systems. The system may include a processor and an electronic module which control operation of a transducer assembly provided at a distal end of a catheter assembly. The system invokes a first processing step or method to collect and store raw angle and line data, as well as one or more of second and third processing steps or methods which adjust for NURD experienced during backlash of a bi-directional imaging system and a fourth processing step or method which performs a line-to-line correlation function.