Showing papers by "Ching Y. Suen published in 1994"

Document processing for automatic knowledge acquisition

Abstract: The knowledge acquisition bottleneck has become the major impediment to the development and application of effective information systems. To remove this bottleneck, new document processing techniques must be introduced to automatically acquire knowledge from various types of documents. By presenting a survey on the techniques and problems involved, this paper aims at serving as a catalyst to stimulate research in automatic knowledge acquisition through document processing. In this study, a document is considered to have two structures: geometric structure and logical structure. These play a key role in the process of the knowledge acquisition, which can be viewed as a process of acquiring the above structures. Extracting the geometric structure from a document refers to document analysis; mapping the geometric structure into logical structure is regarded as document understanding. Both areas are described in this paper, and the basic concept of document structure and its measurement based on entropy analysis is introduced. Logical structure and geometric models are proposed. Both top-down and bottom-up approaches and their entropy analyses are presented. Different techniques are discussed with practical examples. Mapping methods, such as tree transformation, document formatting knowledge and document format description language, are described. >

Analysis and recognition of alphanumeric handprints by parts

Abstract: In this paper, an advanced hierarchical model has been proposed to produce a more effective character recognizer based on the probability of occurrence of the patterns. New definitions such as crucial parts, efficiency ratios, degree of confusion, similar character pairs, etc. are also given to facilitate pattern analysis and character recognition. Using these definitions, computer algorithms have been developed to recognize the characters by parts, including halves, quarters, and sixths. The recognition rates have been analyzed and compared to those obtained from subjective experiments. Based on the results of both computer and human experiments, a detailed analysis of the crucial parts and the Canadian standard alphanumeric character set has been made which revealed some fundamental characteristics of these handprint models. The results should be useful to pattern analysis and recognition, character understanding, handwriting education, and human-computer communication. >

Thinning Methodologies for Pattern Recognition

Abstract: A new thinning algorithm based on controlled deletion of edge regions, G. Dimauro et al graph-based thinning for binary images, S. Suzuki et al a parallel thinning algorithm using the bounding boxes techniques, S. Ubeda invariant thinning, U. Eckhardt & G. Maderlechner analytical comparison of thinning, Y.Y. Zhang & P.S.P. Wang methologies for evaluating thinning algorithms for character recognition, R. Plamondon et al automatic comparison of skeletons by shape matching methods, L. Lam & C.Y. Suen binary and gray-value skeletons - metrics and algorithms, B.J.H. Verwer et al. (Part contents).

Measuring the complexity of rule-based expert systems

Abstract: Many quantitative metrics have already been proposed to measure software complexity for different applications. A similar but different application of these measurements could also be developed for formal evaluation of expert systems (ES) which have some characteristics in common with conventional software. But they also have many distinct features of their own, for example, the rules employed in an experts system do not directly determine the execution order, instead they represent the expertise for solving problems in a general way, so the meanings implied by rules are different from those implied by conventional statements. In this paper, some problems concerning the complexity measurement of rule-based ES are discussed, they include complexity description, complexity model, criteria for measurement, and the measurement. A new approach to measure rulebase complexity is presented. It takes three factors into account: 1) content of the rulebase; 2) connectivity among the rules; and 3) size of the rulebase. In order to assess the effectiveness of this new approach, the complexity of 21 sample rulebase has been measured. The results show that this new measurement is more accurate than that of the “number of rules” of “Buchanan's solution space complexity”; suggesting that it is a better indicator of the rulebase complexity. Furthermore, the computation model of this measurement exhibits characteristics of being meaningful, reasonable, reliable and cost-effective. Another advantage is that the measurement results could be used as an estimator for maintenance or developed efforts, especially in applications where experimental data are lacking.

New algorithms for fixed and elastic geometric transformation models

Abstract: This paper describes a new approach that leads to the discovery of substitutions or approximations for physical transformation by fixed and elastic geometric transformation models. These substitutions and approximations can simplify the solution of normalization and generation of shapes in signal processing, image processing, computer vision, computer graphics, and pattern recognition. In this paper, several new algorithms for fixed geometric transformation models such as bilinear, quadratic, bi-quadratic, cubic, and bi-cubic are presented based on the finite element theory. To tackle more general and more complicated problems, elastic geometric transformation models including Coons, harmonic, and general elastic models are discussed. Several useful algorithms are also presented in this paper. The performance of the proposed approach has been evaluated by a series of experiments with interesting results. >

Document structures: a survey

Abstract: Knowing the structure of a document is the key to successful processing of a document. There exist a variety of definitions of document structures. This paper is a survey of methods describing document structures. Several novel concepts and theoretical analyses are also presented. A document not only has a concrete two-dimensional image but also a conceptual structure which corresponds to human’s thinking. The process of publishing or writing corresponds to encoding the conceptual structure into a concrete structure. Conversely, the concrete structure of the document is decoded into its conceptual one in document processing. In this paper, conceptual and concrete structures are introduced. A complete system for treating both of the conceptual and concrete structures is probably still decades away. As the first stage, this study puts some emphasis on concrete structures, for which, geometric, logical, textual, information, textural, and other structures are described.

RPCT algorithm and its VLSI implementation

Abstract: This paper presents the regional projection contour transformation (RPCT) which transforms a compound pattern or multicontour pattern into a unique outer contour. Two RPCT's, (1) diagonal-diagonal regional projection contour transformation and (2) horizontal-vertical regional projection contour transformation, are presented. They are applicable to a wide range of areas such as image analysis, pattern recognition, etc. A very large scale integration (VLSI) architecture to implement the RPCT has also been designed based on a canonical methodology which maps homogeneous dependence graphs into processor arrays. In this paper, a linear array has been designed, where an N/2-element vector is used to process a pattern with a size of N/spl times/N. It can speed up the recognition process considerably with a time complexity of O(N) compared with O(N/sup 2/) when a uniprocessor is used. >

Quantitative evaluation of expert systems

Abstract: The rapidly increasing application of expert systems has lead to the need to assure their quality, especially in the critical areas where a fault may be serious. Metrics can provide a quantitative basis for such assurance activities. In this paper, we investigate several formal metrics that are designed for measuring the three important characteristics of expert systems: the size, search space, and complexity. The applications of these metrics to assess or predict the quality of expert systems are also addressed. In addition, a comprehensive evaluation and comparison of the metrics is conducted with the aim to assess their validity when applying them to quantify expert systems. >