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Showing papers on "Character (mathematics) published in 1987"


Journal ArticleDOI
TL;DR: A proof is provided for the correctness of Farris's well-known, but previously unproven, algorithm for solving the problem of assigning optimal character states to the hypothetical ancestors of an evolutionary tree under the Wagner parsimony criterion.
Abstract: The problem of assigning optimal character states to the hypothetical ancestors of an evolutionary tree under the Wagner parsimony criterion is examined. A proof is provided for the correctness of Farris's well-known, but previously unproven, algorithm for solving this problem. However, the solution is not, in general, unique, and Farris's method obtains only a subset (generally only one) of the possible solutions. Algorithms that discover other solutions and that resolve ambiguities through the imposition of ancillary criteria are developed and discussed. A method for determining the optimal length of a given tree without actually assigning character states to hypothetical ancestors is described.

538 citations



Patent
04 May 1987
TL;DR: In this paper, a video camera produces an image of a license plate on a vehicle, and a scanning apparatus (100) finds the license plate number in the image, and the identification of the number is verified in a confidence check section (116) by checking for the presence of a state logo.
Abstract: A video camera produces an image of a license plate on a vehicle, and a scanning apparatus (100) finds a license plate number in the image. The identification of the number is verified in a confidence check section (116) by checking for the presence of a state logo. Next, a character extractor (102) identifies individual characters of the number by finding and tracing a contour along interior portions of the character edges, and the contour length, character height, and character width are then checked in a validity checking section (130). A character alignment section (132) corrects for obscuring objects on the license plate, and a license plate frame correction section (134) extracts the characters when a portion thereof is obscured. Once extracted, the characters are recognized by a structural analysis section (136) and a state recognition section (142) recognizes the state logo. A verification section rereads (108) the license plate number utilizing knowledge of the type style used by the state.

167 citations


Book
14 May 1987
TL;DR: It is a truth quite infrequently acknowledged that, in most discussions of works of English fiction, we proceed as if a third of our material was not really there Common prepositions, conjunctions, personal pronouns, and articles, and the verb-forms "was", "be", and "had", make up such a proportion of each of Jane Austen's novels as mentioned in this paper.
Abstract: It is a truth quite infrequently acknowledged that, in most discussions of works of English fiction, we proceed as if a third of our material was not really there Common prepositions, conjunctions, personal pronouns, and articles, and the verb-forms "was", "be", and "had", make up such a proportion of each of Jane Austen's novels There is no doubt that a roughly similar proportion exists in the work of many other English novelists John Burrows shows that in the drawing of character in Jane Austen's writings very common words prove to be intrinsically revealing

158 citations


Journal ArticleDOI
TL;DR: The modular invariance properties of two-dimensional N = 2 superconformal field theories are studied in this paper, where it is shown that the character formulae of the central charge c < 3 unitary highest weight representation for the untwisted algebras can be written in terms of the string functions and the theta functions of the affine su(2) Kac-Moody algebra.

100 citations


Journal ArticleDOI
TL;DR: The character formula of c≪1 unitary representation of N = 2 superconformal algebra is obtained in this article, which can be used to express Waterson's bosonic construction of the algebra in character form.
Abstract: The character formula of c≪1 unitary representation of N=2 superconformal algebra is obtained. As a corollary of our formula, we can easily express Waterson's bosonic construction of the algebra in character form.

77 citations


Patent
29 Apr 1987
TL;DR: In this article, a method and device for reading and recognizing an unknown character on a document, the device measuring the character's waveform amplitude along timed intervals and determining that each measurement is within a predetermined acceptable amplitude range at each interval for an ideal character.
Abstract: A method and device for reading and recognizing an unknown character on a document, the device measuring the character's waveform amplitude along timed intervals and determining that each measurement is within a predetermined acceptable amplitude range at each interval for an ideal character. If all of the measurements of the amplitude are within the acceptable ranges, a recognition signal of the character is generated.

74 citations


Patent
12 Aug 1987
TL;DR: In this article, a distance counting part 5 obtains the distance of the characteristic quantity of a recognizing object character pattern obtained by a characteristic extracting part 4 and the characteristic quantities of respective characters registered in a first dictionary 6 beforehand, and a classifying part 7 makes the smallest distance out of the distance obtained by the distance counting parts 5 into the first candidate character, makes the N character into the recognizing candidate character group from the character with a small distance including the character and adds the character type to display the attribute of respective character to respective recognizing candidate characters.
Abstract: PURPOSE:To correctly recognize a character even in the character having a very similar shape by deciding the character needing a correction and the character type after the correction from the arrangement of the character type of respective first candidate characters, and making the recognizing candidate character having the same character type as the character after the correction from the recognizing candidate character group of the character needing the correction into a first candidate character. CONSTITUTION:A distance counting part 5 obtains the distance of the characteristic quantity of a recognizing object character pattern obtained by a characteristic extracting part 4 and the characteristic quantity of respective characters registered in a first dictionary 6 beforehand. A classifying part 7 makes the smallest distance out of the distance obtained by the distance counting part 5 into the first candidate character, makes the N character into the recognizing candidate character group from the character with a small distance including the character and adds the character type to display the attribute of respective characters to respective recognizing candidate characters. In the character where the character type is changed by a character type changing part 8, a correcting part 9 makes the highest order candidate character out of the candidate character having the same character type as the character type after the changing of the character to change the character type in a second to the N-th candidate characters into the first candidate character.

61 citations


Patent
Gen Sato1
19 May 1987
TL;DR: In this paper, an unknown character is read to form a binary character image, and a plurality of directionality codes are assigned to pixels defining the contour of the character image selectively to define a code-assigned character image.
Abstract: An input, unknown character is optionally read to form a binary character image, and a plurality of directionality codes are assigned to pixels defining the contour of the character image selectively to define a code-assigned character image, which is then subdivided into a plurality of sub-regions in the form of mesh such that each sub-region includes a substantially equal number of assigned codes. Then, a histogram of the codes is defined for each of the sub-regions to form a collection of histograms for the input character. The input character is compared with each of registered, known characters, each having a collection of similar histograms, and the one having a greatest similarity is selected to identify the input character. The similarity is determined by calculating a distance between the histograms of the input character and the histograms of the each of the registered characters. Preferably, the binary character image is subjected to line-broadening processing prior to the step of assigning the codes.

59 citations


Journal ArticleDOI
TL;DR: In this paper, the authors extend Harish-Chandra's theorem to non-connected, reductive groups over a p-adic field of characteristic zero and show that the distribution character of an admissible, irreducible representation of a (connected) reductive group is locally integral.
Abstract: In this paper, we extend to non-connected, reductive groups over p-adic field of characteristic zero Harish-Chandra's theorem on the local integrability of characters. Harish-Chandra's theorem states that the distribution character of an admissible, irreducible representation of a (connected) reductive p-adic group is locally integrable. We show that this extends to any reductive group; just as in the connected case, one even gets a very precise control over the singularities of the character along the singular elements. As will be seen, the proof in the non-connected case is an easy extension of Harish-Chandra's. The reader may wonder why we have bothered to write its generalization completely. The reason is that the original article [8] does not contain proofs for the crucial lemmas, and this makes it impossible to explain why the theorem extends. Because this result is needed for work of Arthur and the author on base change, it has been thought necessary to give complete arguments.

57 citations


Patent
08 Jul 1987
TL;DR: In this article, the optical character reader (OCR) utilizes prioritized horizontal OR ranges for enhanced accuracy and ease of use, which can be used for relatively small in size price tags.
Abstract: The invention provides an optical character reader (OCR) utilizing prioritized horizontal OR ranges for enhanced accuracy and ease of use. A light source illuminates a price tag or the like on which characters have been imprinted generally along a horizontal direction of the sheet. A lens system images the characters onto an image sensor having a field of vision covering a plurality of characters, the image sensor including a plurality of photo-electric conversion elements arranged in a matrix. A binary coding circuit digitizes outputs of the photo-electric conversion elements, which define picture elements (pixels), of an image in the field of vision of the image sensor, into binary signals representing black and white picture elements. A hand holdable scanner incorporates the light source, image sensor, lens system and binary coding circuit. An identifying circuit identifies characters from binary-coded data. The OCR utilizes at least two horizontal OR ranges in the field of vision of the image sensor. When the horizontal OR range of higher priority detects a character line, the result of character line detection is output. When none of the horizontal OR ranges detects a character line, it is determined that there is no character line. The character line detecting operation of each of the horizontal OR ranges is the same as that in the conventional OCR. However, in the OCR according to the present invention, the horizontal OR ranges are spread horizontally. Therefore, even in the case of a price tag which is long enough to have characters arranged along one of its sides, the character line or lines can be positively detected. Since at least two horizontal OR ranges are provided in the field of vision of the image sensor, therefore the pattern of the background of the price tag and the characters on the price tag can be distinguished from each other. This means that the OCR can be used for relatively small in size price tags. The OCR conserves electric power when it is not actively "reading" data by suspending its character identifying operations when not needed. Lines having no characters are identified and, in response, character identifying operations are stopped.

Patent
02 Jun 1987
TL;DR: In this paper, the outline of a character is decomposed into a plurality of blocks [P 1, P n ] (where P 1 and P n are a start point and an end point of an arbitrary block respectively) each defined by a univalent function involving x as a variable.
Abstract: An apparatus for processing character or pictorial image or the like for splitting the outline of a character, which is developed on x- and y-coordinates, into a plurality of blocks [P 1 , P n ] (where P 1 and P n are a start point and an end point of an arbitrary block respectively) each defined by a univalent function involving x as a variable, then producing block data to specify the shape of each block, and storing a set of such block data as the compressed data of one character to accomplish compression of the data.

Journal ArticleDOI
TL;DR: The character index combined with modified Gay triangles was found suitable for revealing the structure of the material, which showed mainly one-dimensional variation.
Abstract: A grouping of transformations is proposed: 1) “Element transformations”, aimed at changing relations between elements within a single character vector; and 2) “vector transformations”, aimed at changing relations between different character vectors. Logarithmic element transformation seemed suitable for revealing variation in size characters. Principal coordinate analysis (PCO) was appropriate for determination of dimensionality and structural extremes (parentage). Due to polynomial distortions, however, variation in extreme populations was underestimated and variation in intermediate populations exaggerated. A “character index”, the mean of a specimen's ranged characters, is suggested to replace Anderson's hybrid index. Knowledge of parentage and parental maxima, but not of variation in pure parental populations, is required. The character index combined with modified Gay triangles was found suitable for revealing the structure of the material, which showed mainly one-dimensional variation. The material analysed comprised Argyranthemum broussonetu, A. frutescens, a hybrid swarm and experimental F1 hybrids between these species; and A. sundingu, which was found to be a stabilized hybrid derivative, probably evolved by hybrid speciation with external barriers.



Patent
23 Dec 1987
TL;DR: A spelling error correcting system comprises means for storing a number of correctly spelled words, each of which can be accessed by one or more combinations of character categories, each combination consisting of m (m is a constant satisfying m < n) character categories of the character categories included in the word and sorted based on a predetermined rule associated with character categories as mentioned in this paper.
Abstract: A spelling error correcting system comprises means for storing a number of correctly spelled words, each of which can be accessed by one or more combinations of character categories, each combination consisting of m (m is a constant satisfying m < n) character categories out of n (n is a constant) leading character categories of the character categories included in the word and sorted based on a predetermined rule associated with character categories; means for sorting character categories included in an input word based on the rule for sorting; means for obtaining all combinations of m character categories out of n leading character categories of the sorted character categories; means for reading from the storing means correctly spelled words based on each of the obtained combinations of character categories; and means for matching the input word with each of the read words.

Journal ArticleDOI
TL;DR: In this article, the authors derive the duties of the historian of the family from the ethical philosophy of Immanuel Kant, and criticise the following tendencies in the treatment of the history of families.
Abstract: This is a deliberately controversial piece, deriving the duties of the historian of the family from the ethical philosophy of Immanuel Kant. It criticizes the following tendencies in the treatment ...

Proceedings ArticleDOI
01 Aug 1987
TL;DR: An original and fast filling algorithm based on vertical scan line sweep and contour tracking of a presorted shape description allows filling of character shapes with real subpixel resolution, which is very well adapted for direct character generation on non-impact printers and suitable for character rasterization in typographic computer-aided design systems.
Abstract: An original and fast filling algorithm based on vertical scan line sweep and contour tracking of a presorted shape description allows filling of character shapes with real subpixel resolution. Identical parts of a character lying at a different phase in respect to the grid will have a dissimilar discrete look. Grid constraints are applied in order to force given parts of a character (stems, serifs) to attain identical phasing. So that several contraints may be applied, degrees of freedom are provided in the form of stretchable null-segments inserted at particular locations in the character outline description. Grid constraints are also applied to avoid discrete arcs with an isolated pixel or a long horizontal or vertical run. The type of constraints applied to parts of a character consists only of horizontal or vertical subpixel translations. The resulting character description therefore remains nearly identical to the original description. The processing time used to apply grid constraints is negligible, compared with the time needed for character scan-conversion and filling. Hence, this method is very well adapted for direct character generation on non-impact printers. It is also suitable for character rasterization in typographic computer-aided design systems.

Book
01 Jan 1987
TL;DR: The Emergent Voice: The Word Within Its Texts The Word Assumes Its Raiment and Other Appropriate Garb The Word, Thus Adorned, Bodies Forth Itself The Spiritual Legacy in the Word Conclusion as mentioned in this paper
Abstract: Series Foreword Preface The Community in Her Words The Crafting of the Word: Art, Artistry and Artist--Stages of Ownership The Emergent Voice: The Word Within Its Texts The Word Assumes Its Raiment and Other Appropriate Garb The Word, Thus Adorned, Bodies Forth Itself The Spiritual Legacy in the Word Conclusion

Patent
Michiyoshi Tachikawa1
02 Jul 1987
TL;DR: In this article, a character recognition method includes a step of assigning one of a plurality of predetermined directionality codes to each of the pixels defining the contour of a character pattern.
Abstract: A character recognition method includes a step of assigning one of a plurality of predetermined directionality codes to each of the pixels defining the contour of a character pattern. Then, the character pattern, to which the directionality codes have been assigned, is subdivided into a plurality of mesh regions. In this case, in accordance with the present invention, the character pattern is not directly subdivided into mesh regions, and, instead, the character pattern is first subdivided into a first plurality of sub-regions and then the first plurality of sub-regions are converted into a second plurality, which is smaller in number than the first plurality, of mesh regions by combining at least some of said first plurality of sub-regions. Such a two-step subdivision process of a character pattern is advantageous in absorbing fluctuations caused by modifications of the character pattern, such as hand-written characters.

Patent
Kenji Yasujima1, Hashimoto Masao1
17 Dec 1987
TL;DR: In this paper, a method of creating a dictionary for character recognition using a document on which identical characters are aligned in a scanning direction and a mark indicating a size of a character line including the characters is positioned in the vicinity of the aligned characters.
Abstract: A method of creating a dictionary for character recognition uses a document on which identical characters are aligned in a scanning direction and a mark indicating a size of a character line including the characters is positioned in the vicinity of the aligned characters. An image processing is carried out for dot patterns of the aligned characters, and one dot pattern to be registered in a dictionary is produced. Then, the produced dot pattern is registered in a dictionary together with a corresponding character code data.

Journal ArticleDOI
01 Dec 1987
TL;DR: In this article, the weighted orbital integral of a supercuspidal matrix coefficient as a multiple of the corresponding character was evaluated on ap-adic groups. But the authors did not consider the case where the matrix coefficients are drawn from the geometric side of the trace formula.
Abstract: Weighted orbital integrals are the terms which occur on the geometric side of the trace formula. We shall investigate these distributions on ap-adic group. We shall evaluate the weighted orbital integral of a supercuspidal matrix coefficient as a multiple of the corresponding character.




Journal ArticleDOI
TL;DR: In this paper, three different length scales have been identified for which the character of the medium-range order (MRO) in a glass can be described in qualitatively different ways, and documented cases of MRO for each length scale are discussed.
Abstract: Three different length scales have been identified for which the character of the medium-range order (MRO) in a glass can be described in qualitatively different ways. Documented cases of MRO for each length scale are discussed

Journal ArticleDOI
TL;DR: The paper presents an algorithm for the estimation of skeletons of thick characters that directly identifies the core pixels of the skeleton forming the core skeletal segments based on labeling of the character boundary with some local properties.
Abstract: The paper presents an algorithm for the estimation of skeletons of thick characters. We directly identify the core pixels of the skeleton forming the core skeletal segments based on labeling of the character boundary with some local properties. The core skeletal pixel is defined as the midpoint of a line segment normal to the boundary pixels. These core skeletal segments are extended and joined systematically based on certain global properties resulting in the final skeleton. The algorithm is independent of the width of the character and is capable of yielding a skeleton close to our intuitive notion of character shape. The topological description of the character is constructed more or less as a by-product of the skeletomization process. The description forms the basis for character recognition using syntactic methods. The algorithm is well suited for parallel implementation.

Patent
16 Dec 1987
TL;DR: In this article, an optical alphanumeric character reader scans each printed line in the direction of its height from its beginning to its end sequentially at a predetermined interval, and the intervals thus scanned are identified either as containing a printed part or as being all white and are represented respectively by a "black bit" and a "white bit" corresponding to different logical numbers.
Abstract: According to a method of the present invention, an optical alphanumeric character reader scans each printed line in the direction of its height from its beginning to its end sequentially at a predetermined interval. The intervals thus scanned are identified either as containing a printed part or as being all white and are represented respectively by a "black bit" and a "white bit" corresponding to different logical numbers. For each white bit or each continuous array of white bits sandwiched between black bits, the number of white bit or bits between the sandwiching black bits is counted. The histogram of such counted numbers has two peaks corresponding to gaps between letters and those between words and serves to determine a threshold value by which a space between words can be detected by the optical character reader.

Patent
04 Mar 1987
TL;DR: In this paper, a character image generating circuit includes a text buffer for storing character code data corresponding to one page, a first memory for storing the character image code corresponding to a section of one page and a second memory for encoding the compressed character image codes corresponding to other sections.
Abstract: A character image generating circuit includes a text buffer for storing character code data corresponding to one page, a first memory for storing character image data corresponding to a section of one page, and a second memory for storing compressed character image data corresponding to one page. A depiction control unit coupled with a font memory is provided for converting the character code data, a section at a time from the text buffer, to character image data which is temporarily stored in the first memory. The depiction control unit also compresses the character image data obtained from the first memory to produce compressed character image data which is stored in the second memory. The second memory further receives compressed character image data of other sections. A reconstruction circuit is provided for reconstructing the compressed character image data of one page from the second memory back to the original character image data.

Patent
28 Jul 1987
TL;DR: The RDS system of the European Broadcasting Union (RDS) as discussed by the authors allows the transmission of a message longer than 64 characters, where the complete message is segmented into portions of no more than 60 characters and message elements are formed, to be transmitted in successive groups, associating with each successive portion a prefix of four control characters thus composed: a message identifier character, susceptible of assuming one of two configurations and adapted to maintain the same configuration in the successive groups of bits for the duration of a same message.
Abstract: Message elements are formed, consisting of 64 characters, and a succession of groups of information bits is modulated on the supplementary subcarrier, each group comprising a code adapted to identify it as a text-­containing group, a preset number of characters constituting a segment of the message element and a four-bit address adapted to locate said segment within the complete element, according to the RDS system of the European Broadcasting Union. According to the invention, for the transmission of a message longer than 64 characters the complete message is segmented into portions of no more than 60 characters and message elements are formed, to be transmitted in successive groups, associating with each successive portion a prefix of four control characters thus composed: a) a message identifier character, susceptible of assuming one of two configurations and adapted to maintain the same configuration in the successive groups of bits for the duration of a same message, and of assuming the other configuration when a different message begins; b) a language identifier character, designating the language in which the message is written; c) a continuity index character, identifying the message element contained in the group being transmitted; d) a message length character, identifying the number of message elements which compose the complete message.