541 results about "Time integral" patented technology

A device and a method for measuring body fluid-related metrics using spectrophotometry to facilitate therapeutic interventions aimed at restoring body fluid balance. The specific body fluid-related metrics include the absolute volume fraction of water in the extravascular and intravascular tissue compartments, as well as the shifts of water between these two compartments. The absolute volume fraction of water is determined using algorithms where received radiation measured at two or more wavelengths are combined to form either a single ratio, a sum of ratios or ratio of ratios of the form log[R(λ1) / R(λ2)] in which the received radiation in the numerator depends primarily on the absorbance of water and the received radiation in the denominator depends primarily on the absorbance of water and the sum of the absorbances of non-heme proteins, lipids and water in tissue. The difference between the fraction of water in the intravascular fluid volume (“IFV”) and extravascular fluid volume (“EFV”) compartments are also determined using a differential method that takes advantage of the observation that pulsations caused by expansion of blood vessels in the skin as the heart beats produce changes in the received radiation at a particular wavelength that are proportional to the difference between the effective absorption of light in the blood and the surrounding tissue. This difference, integrated over time, provides a measure of the quantity of the fluid that shifts into and out of the capillaries. A mechanism for mechanically inducing a pulse is built into the device to improve the reliability of measurements of IFV−EFV under weak-pulse conditions.

A method and apparatus that utilizes a force-time integral for real time estimation of lesion size in catheter-based ablation systems. The apparatus measures the force exerted by a contact ablation probe on a target tissue and integrates the force over an energization time of the ablation probe. The force-time integral can be calculated and utilized to provide an estimated lesion size (depth, volume and / or area) in real time. The force-time integral may also account for variations in the power delivered to the target tissue in real time to provide an improved estimation of the lesion size. In one embodiment, the force metric can be used as feedback to establish a desired power level delivered to the probe to prevent steam popping.

Simulating a long exposure-time image from a sequence of short exposure-time images captured at slightly different times. The sequence of images is combined in a temporal integration process to create a long exposure image that simulates the output from a still camera, steadied by a tripod, whose light-sensitive material has been exposed to the same scene from the time of the beginning of the first input image of the sequence to the last image of the input sequence. The method overcomes limitations of hand-held video and image recording devices, allowing the user to easily create effects normally associated with high-end digital still cameras under expert control.

Disclosed is a system and method for using optical flow to detect objects moving past a camera and to select images of the moving objects. A shopping cart, for example, may be detected by subdividing an image into a plurality of image blocks; comparing the blocks to a preceding image to determine the motion of the portion of the object pictured; associating the most common motion with the shopping cart. The motion of the cart may also be integrated over time for purposes of tracking cart motion and selecting a subset of the captured images for object recognition processing. Detection of the cart and image selection improves computational efficiency an increase merchandise throughput.

A simple method and device for accurately measuring flash memory cell current. The sensing scheme comprises an integrator, an analog to digital converter, and a digital to analog converter. The method comprises the acts of applying an input current and a feedback output current to a summer, integrating the resulting summer output over time, passing the integrated output to a clocked comparator, outputting a comparator output which controls a feedback circuit that keeps the integrator's voltage at the same level as a reference voltage, and outputting a digital average current to a counter. Delta sigma modulation (averaging) is employed to cancel out noise that would otherwise affect the cell current measurement.