Character (mathematics)

About: Character (mathematics) is a research topic. Over the lifetime, 46723 publications have been published within this topic receiving 411412 citations.

Method of producing character templates using unsegmented samples

Abstract: A method for producing, or training, a set of character templates uses as the source of training samples an image source of character images, called glyphs, that are not previously segmented or isolated for training. Also used is a labeled glyph position data structure that includes, for each glyph in the image source, a glyph image position in the image source associating an image location of the glyph with a character label paired with the glyph image position that indicates the character in the character set being trained. The labeled glyph position data is used to identify a collection of glyph sample image regions in the image source for each character in the character set; each glyph sample image region is large enough to contain a glyph and typically contains adjacent glyphs for other characters. The invention mathematically characterizes the template construction problem using unsegmented samples as an optimization problem that optimizes a function that represents the set of character templates being trained as an ideal image to be reconstructed to match the input image. The method produces all of the character templates contemporaneously by using a novel pixel scoring technique that implements an approximation of a maximum likelihood criterion subject to a constraint on the templates produced which holds that foreground pixels in adjacently positioned character images have substantially nonoverlapping foreground pixels. The character templates produced may be binary templates or arrays of pixel color probability values, and may also have substantially disjoint supports, such that adjacently imaged templates have substantially no overlapping foreground pixels.

On the character of Weil’s representation

Abstract: The importance of certain representations of symplectic groups, usually called Weil representations, for the general problem of finding representations of certain group extensions is made explicit. Some properties of the character of Weil's representation for a finite symplectic group are given and discussed, again in the context of finding representations of group extensions. As a by-product, the structure of anisotropic tori in symplectic groups is given. I. In the title above a pun is intended, for this paper is concerned with two aspects of the celebrated Weil representation-first with its character in the sense of character theory in group representations, then with its character in the more everyday sense of its nature. I think also that the character (in the technical sense) of the Weil representation says something about the character in the general sense. In any case, both facts presented here seem to me rather striking. We proceed to describe them. Let F be a field of characteristic not 2, and let J{(F) be the group of (n + 2) x (n + 2) matrices of the form /1 X1 . .x X Z\ XI xn 1 1 Q Yi

Chinese word segmentation based on maximum matching and word binding force

Abstract: A Chinese word segmentation algorithm based on forward maximum matching and word binding force is proposed in this paper. This algorithm plays a key role in post-processing the output of a character or speech recognizer in determining the proper word sequence corresponding to an input line of character images or a speech waveform. To support this algorithm, a text corpus of over 63 millions characters is employed to enrich an 80,000-words lexicon in terms of its word entries and word binding forces. As it stands now, given an input line of text, the word segmentor can process on the average 210,000 characters per second when running on an IBM RISC System/6000 3BT workstation with a correct word identification rate of 99.74%.

Words versus character n-grams for anti-spam filtering

Abstract: The increasing number of unsolicited e-mail messages (spam) reveals the need for the development of reliable anti-spam filters. The vast majority of content-based techniques rely on word-based repr...