Abstract: A method for determining a physiologic characteristic associated with cardiac function in a subject comprising the steps of providing at least one electromagnetic radiation absorption measurement, providing demographic information reflecting the subject's physical condition, determining a temporal plethysmographic value from the electromagnetic radiation absorption measurement, and determining at least one physiologic characteristic from the temporal plethysmographic value and demographic information by using a predetermined phenomenological model that is adapted to provide an estimate of a blood volume-time relationship proximate the heart and compute at least one physiologic characteristic associated with cardiac function based on the estimated blood volume-time relationship.

Abstract: A pattern recognition device has a drawing area upon which a user may draw an image with a pen designed for that purpose. In a first option available to the user, a user-drawn image is analyzed and saved in the memory of a computer. In a second option, the image is analyzed and an image in a pre-existing image database of the computer is retrieved which most nearly resembles the drawn image. In both options, the user-drawn image is transformed into a target image which is then subdivided into a plurality of image subdivisions and each image subdivision is then further subdivided into sectors. A first binary value is assigned to each sector to indicate whether or not it has at least some graphical data and a second binary value is assigned to indicate whether or not the graphical data occupies a predetermined percentage of the area of the sector. These binary values are strung together, converted into an integer, and the integers are stored in a computer memory.