Abstract: The present invention is a method of deriving a reflectance function that analytically approximates the light reflected from an object model in terms of the spherical harmonic components of light. The reflectance function depends upon the intensity of light incident at each point on the model, the intensity of light diffusely reflected, and the intensity of light broadened-specularly reflected in the direction of an observer. This reflectance function is used in the process of machine vision, by allowing a machine to optimize the reflectance function and arrive at an optimal rendered image of the object model, relative to an input image. Therefore, the recognition of an image produced under variable lighting conditions is more robust. The reflectance function of the present invention also has applicability in other fields, such as computer graphics.

Abstract: The present invention is a method of deriving a reflectance function that analytically approximates the light reflected from an object model in terms of the spherical harmonic components of light. The reflectance function depends upon the intensity of light incident at each point on the model, but excludes light originating from below a local horizon, therefore not contributing to the reflectance because of the cast shadows. This reflectance function is used in the process of machine vision, by allowing a machine to optimize the reflectance function and arrive at an optimal rendered image of the object model, relative to an input image. Therefore, the recognition of an image produced under variable lighting conditions is more robust. The reflectance function of the present invention also has applicability in other fields, such as computer graphics.

Abstract: The Torrance-Sparrow model of off-specular reflection is recast in a significantly simpler and more transparent form in order to render a spherical-harmonic decomposition more feasible. By assuming that a physical surface consists of small, reflecting facets whose surface normals satisfy a normal distribution, the model captures the off-specular enhancement of the reflected intensity distribution often observed at large angles of incidence and reflection, features beyond the reach of the phenomenological broadening models usually employed. In passing we remove a physical inconsistency in the original treatment, restoring reciprocity and correcting the dependence of reflectance on angle near grazing incidence. It is noted that the results predicted by the model are relatively insensitive to values of its one parameter, the width of the distribution of surface normals.

Abstract: The Torrance-Sparrow model of off-specular reflection is recast in a significantly simpler and more transparent form in order to render a spherical-harmonic decomposition more feasible. By assuming that a physical surface consists of small, reflecting facets whose surface normals satisfy a normal distribution, the model captures the off-specular enhancement of the reflected intensity distribution often observed at large angles of incidence and reflection, features beyond the reach of the phenomenological broadening models usually employed. In passing we remove a physical inconsistency in the original treatment, restoring reciprocity and correcting the dependence of reflectance on angle near grazing incidence. It is noted that the results predicted by the model are relatively insensitive to values of its one parameter, the width of the distribution of surface normals.

Abstract: The present invention is a method of deriving a reflectance function that analytically approximates the light reflected from an object model in terms of the spherical harmonic components of light. The reflectance function depends upon the intensity of light incident at each point on the model, but excludes light originating from below a local horizon, therefore not contributing to the reflectance because of the cast shadows. This reflectance function is used in the process of machine vision, by allowing a machine to optimize the reflectance function and arrive at an optimal rendered image of the object model, relative to an input image. Therefore, the recognition of an image produced under variable lighting conditions is more robust. The reflectance function of the present invention also has applicability in other fields, such as computer graphics.

Abstract: The present invention is a method of deriving a reflectance function that analytically approximates the light reflected from an object model in terms of the spherical harmonic components of light. The reflectance function depends upon the intensity of light incident at each point on the model, the intensity of light diffusely reflected, and the intensity of light broadened-specularly reflected in the direction of an observer. This reflectance function is used in the process of machine vision, by allowing a machine to optimize the reflectance function and arrive at an optimal rendered image of the object model, relative to an input image. Therefore, the recognition of an image produced under variable lighting conditions is more robust. The reflectance function of the present invention also has applicability in other fields, such as computer graphics.

Abstract: The results of a full-text, document search by a character string search processor are treated as vector patterns whose elements become a term match grade by use of a membership function of the term match frequency. The closest pattern to the query pattern is found by the similarity between the query pattern and each of the filed sample patterns. The similarity is calculated by use of fuzzy-logic. The similarity is ranked in order of similarity magnitude, thereby reducing the search time. The search time can be shortened by categorizing the filed patterns by term set and similarity to a cluster center pattern. If the cluster center patterns are stored, the closest cluster address can be inferred by fuzzy logic inference from the match between the query document and the term set or the similarity of the query to the cluster center.

Abstract: A fuzzy syllogistic inference processing system for use with a chain of implications when links in the chain have various measures between 0 and 1 of confidence. Analog signals that are linearly related to the confidence measures are generated and compared. The chain of implications is given a confidence measure that is equal to that of the inference consequence of the last major premise in the chain provided that each major premise in the chain has a confidence measure that is larger than the confidence measure of the complement or negation of its antecedent in the chain.

Abstract: A fuzzy syllogistic inference processing system for use with a chain of implications when links in the chain have various measures between 0 and 1 of confidence. Analog signals that are linearly related to the confidence measures are generated and compared. The chain of implications is given a confidence measure that is equal to that of the inference consequence of the last major premise in the chain provided that each major premise in the chain has a confidence measure that is larger than the confidence measure of the complement or negation of its antecedent in the chain.

Abstract: A transferred electron device is described in which the charge of the drifting packets is imaged perpendicular to the charge-packet direction so that essentially all of the packet-averaged, space-charge field is normal to the drift direction. This permits continuous formation of contiguous charge packets.

Abstract: Semiconductor structures suitable for repeated velocity overshoot are described. The structure comprises at least two velocity overshoot sections with each section comprising a first semiconductor region having a rapid change in potential and a dimension such that the carrier transit time is comparable to or shorter than the mean scattering time and a second semiconductor region having a more gradual change in potential and a dimension such that the carrier transit time is sufficient to allow the energy relaxation time to be exceeded.