• Journal of the Korea Society of Computer and Information
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• v.10 no.4 s.36
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• pp.385-396
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• 2005

In this paper, a new structural approach to on-line signature verification is presented. A primitive pattern is defined as a part segmented by a local minimal position of speed. And a structural description of signature is composed of subpatterns which are defined as such forms as rotation shape, cusp shape and bell shape, acquired by composition of the primitives regarding the directional changes. As the matching method to find identical parts between two signatures, a modified DP(dynamic programming) matching algorithm is presented. And also, variation and complexity of local parts are computed from the training samples, and reference model and decision boundary are derived from these. Error rate, execution time and memory usage are compared among the functional approach, the parametric approach and the proposed structural approach. It is found that the average error rate can be reduced from 14.2% to 4.05% when the local parts of a signature are weighted and the complexity is used as a factor of decision threshold. Though the error rate is similar to that of functional approaches. time consumption and memory usage of the proposed structural approach are shown to be very effective.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.6
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• pp.1345-1352
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• 2010

The structural approach in the signature verification, representing a signature as a structural form of local primitives, shows an excellent performance since it counts in the local characteristics such as local variation, stroke complexity, and etc. However, this method has a problem of template data sizing which can not fix the number of subpatterns comprising a signature. In this paper, we proposed a new algorithm to reduce the signature data into a fixed size by selecting a fixed number of subpatterns which is considered as important parts. As a result, it shows more excellent performance when the fixed sized sub-patterns is applied with local weights extracted from variational characteristics and complexities in local part. And the number of subpatterns representing a signature reference model can be fixed under a certain number of segments determined appropriately.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.1
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• pp.185-196
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• 1999

In this dissertation, a new off-line recognition system is proposed using a subgraph pattern, neural network. After thinning is applied to input characters, balance having a noise elimination function on location is performed. Then as the first step for recognition procedure, circular elements are extracted and recognized. From the subblock HT, space feature points such as endpoint, flex point, bridge point are extracted and a subgraph pattern is formed observing the relations among them. A region where vowel can exist is allocated and a candidate point of the vowel is extracted. Then, using the subgraph pattern dictionary, a vowel is recognized. A same method is applied to extract horizontal vowels and the vowel is recognized through a simple structural analysis. For verification of recognition subgraph in this paper, experiments are done with the most frequently used Myngjo font, Gothic font for printed characters and handwritten characters. In case of Gothic font, character recognition rate was 98.9%. For Myngjo font characters, the recognition rate was 98.2%. For handwritten characters, the recognition rate was 92.5%. The total recognition rate was 94.8% with mixed handwriting and printing characters for multi-font recognition.

• MISULJARYO - National Museum of Korea Art Journal
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• v.97
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• pp.69-86
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• 2020

Haenghaeng Ilgi (Diary of a Royal Trip) (koo 7152; hereafter Ilgi) in the collection of the National Museum of Korea provides an account of Crown Prince Sado's incognito royal visit to Pyeongyang in the fourth month of 1761. Ilgi was written by Ham Daeil, a low-ranking military officer in Pyeongyang. Ham was singled out for praise by Crown Prince Sado (1735-1762) and served the prince from the seventh day of the fourth month to the first day of the fifth month. Ilgi documented the deeds of Crown Prince Sado during this period and provides detailed information on his incognito visit to Pyeongyang, which was not officially recorded. Ilgi shows characteristics differentiating it from many other diaries. For example, the quality of the paper, neat handwriting, and well-organized sentences differ from those of common diaries. These distinctions indicate that Ilgi is closer to an official document than a private diary written by an individual. Since Ilgi records Crown Prince Sado's incognito visit to Pyeongyang, is only vaguely known otherwise, its contents need to be examined in terms of whether or not they are fully factual. As the first step in such verification, It is traced that Ham Daeil's family history which turned out to match what is written in Ilgi. Moreover, Ilgi mentions about Prince Crown Sado's writing a piece of calligraphy, and a matching piece of calligraphy written by Sado still survives today. It can be confirmed that the contents of Ilgi are factual in at least these regards. However, although Crown Prince Sado was known to have met people from various social classes during his visit to Pyeongyang, Ilgi focuses only on Crown Prince Sado and Ham Daeil. This suggests the possibility that the surviving version of Ilgi may be an edited condensation based on original texts containing more complete information on Crown Prince Sado's visit. Ilgi is presumed to have been produced during the generation of Ham Jeonghui, a son of Ham Daeil. The dates of birth and death of Ham Daeil fall during the reign of King Yeongjo. It is unlikely that any records regarding Crown Prince Sado would have been published while King Yeongjo, who was hostile to Sado, ruled the country. Ilgi also provides strong evidence that Ham Jeonghui presented the subsequent king, King Jeongjo, with the calligraphy by Crown Prince Sado and the diary. It is unclear if the book Ham Jeonghui presented him was the same as the extant version of Ilgi. Nonetheless, considering the situation at the time when King Jeongjo was pursuing several projects to honor his father Sado, it is highly probable that Ilgi was produced during the reign of King Jeongjo. The periods of presenting the calligraphy and the diary respectively overlapped with the production of Hyeollyungwon, the royal tomb of Crown Prince Sado, and Sado's sixtieth birthday. Therefore, is it considered reasonable that Ham Jeonghui produced Ilgi to promote his own social ambitions.