• The Journal of the Acoustical Society of Korea
• /
• v.25 no.1E
• /
• pp.20-24
• /
• 2006

In this paper, we focused on the real time implementation of a speech recognition system with medium size of vocabulary considering its application to a mobile phone. First, we developed the PC based variable vocabulary word recognizer having the size of program memory and total acoustic models as small as possible. To reduce the memory size of acoustic models, linear discriminant analysis and phonetic tied mixture were applied in the feature selection process and training HMMs, respectively. In addition, state based Gaussian selection method with the real time cepstral normalization was used for reduction of computational load and robust recognition. Then, we verified the real-time operation of the implemented recognition system on the TMS320C6201 EVM board. The implemented recognition system uses memory size of about 610 kbytes including both program memory and data memory. The recognition rate was 95.86% for ETRI 445DB, and 96.4%, 97.92%, 87.04% for three kinds of name databases collected through the mobile phones.

• MALSORI
• /
• v.68
• /
• pp.115-126
• /
• 2008

In this paper, we propose a vocabulary coverage improvement method for embedded continuous speech recognition (CSR) using knowledgebase. A vocabulary in CSR is normally derived from a word frequency list. Therefore, the vocabulary coverage is dependent on a corpus. In the previous research, we presented an improved way of vocabulary generation using part-of-speech (POS) tagged corpus. We analyzed all words paired with 101 among 152 POS tags and decided on a set of words which have to be included in vocabularies of any size. However, for the other 51 POS tags (e.g. nouns, verbs), the vocabulary inclusion of words paired with such POS tags are still based on word frequency counted on a corpus. In this paper, we propose a corpus independent word inclusion method for noun-, verb-, and named entity(NE)-related POS tags using knowledgebase. For noun-related POS tags, we generate synonym groups and analyze their relative importance using Google search. Then, we categorize verbs by lemma and analyze relative importance of each lemma from a pre-analyzed statistic for verbs. We determine the inclusion order of NEs through Google search. The proposed method shows better coverage for the test short message service (SMS) text corpus.

• Proceedings of the IEEK Conference
• /
• 2003.07e
• /
• pp.2419-2422
• /
• 2003

To improve performance of sentence speech recognition systems, we need to consider perplexity of language model and the number of words of dictionary for increasing vocabulary size. In this paper, we propose a language model of VCCV units for sentence speech recognition. For this, we choose VCCV units as a processing units of language model and compare it with clauses and morphemes. Clauses and morphemes have many vocabulary and high perplexity. But VCCV units have small lexicon size and limited vocabulary. An advantage of VCCV units is low perplexity. This paper made language model using bigram about given text. We calculated perplexity of each language processing unit. The perplexity of VCCV units is lower than morpheme and clause.

• Korean Journal of Child Studies
• /
• v.25 no.2
• /
• pp.19-39
• /
• 2004

Mothers of 58 20-month-olds in Seoul, the Republic of Korea, completed vocabulary checklists for their children. When vocabulary level was taken into account, children's vocabularies contained relatively greater proportions of nouns than other word classes, and more verbs than adjectives or closed-class words. Correlations among word classes showed that each word class was consistently positively correlated with every other class. Girls' vocabularies showed evidence of being larger than boys. Large individual differences in the sizes of children's vocabularies were found. Factors that influence vocabulary size and can account for gender and individual differences are discussed. Noun prevalence in the vocabularies of children learning to speak Korean, and the merits of several theories that may account for this word-class prevalence pattern, are evaluated.

• Phonetics and Speech Sciences
• /
• v.14 no.3
• /
• pp.41-49
• /
• 2022

The average acoustic distribution of American English speakers was statistically compared with the English-speaking patterns of gifted students in a Science Academy in Korea. By analyzing speech recordings, the duration time of which is much longer than in previous studies, this research identified the degree of acoustic proximity between the two parties and the predictability of English academic achievement of gifted high school students. Long-term spectral acoustic power distribution vectors were obtained for 2,048 center frequencies in the range of 20 Hz to 20,000 Hz by applying an long-term average speech spectrum (LTASS) MATLAB code. Three more variables were statistically compared to discover additional indices that can predict future English academic achievement: the receptive vocabulary size test, the cumulative vocabulary scores of English formative assessment, and the English Speaking Proficiency Test scores. Linear regression and correlational analyses between the four variables showed that the receptive vocabulary size test and the low-frequency vocabulary formative assessments which require both lexical and domain-specific science background knowledge are relatively more significant variables than a basic suprasegmental level English fluency in the predictability of gifted students' academic achievement.

• The Journal of the Korea Contents Association
• /
• v.17 no.4
• /
• pp.331-341
• /
• 2017

This paper aims to analyze English vocabulary of the North Korean textbooks diachronically using the constructed English textbook corpus. The North Korea English textbooks attained from Information Center on North Korea of the Ministry of Unification are divided into before and after Kim Jong-Il era for the year of 1996 in which the curriculum revision has been conducted. They are stored as text files to analyse vocabularies using WordSmith Tools 7.0. The vocabulary size of the revised textbooks increased after the curriculum reorganization, but the number of vocabulary types and vocabulary diversity decreased. After the curriculum revision, it was found that lots of vocabulary related to the establishment of the Kim Jong-Il system appeared as the keyword. It was also found that some vocabularies reflected the economic and social life of North Korea. In addition, through comparison of the 100 high-frequency word list and keywords, it can be concluded that the vocabulary of the English textbooks of North Korea is gradually changing into communicative contents from contents related with written language.

• Journal of Korea Multimedia Society
• /
• v.13 no.4
• /
• pp.496-503
• /
• 2010

Speech recognition system is developed of standalone, In case of a mobile terminal using that low recognition rate represent because of limitation of memory size and audio compression. This study suggest vocabulary recognition highest performance improvement system for separate acoustic search and lexical search. Acoustic search is carry out in mobile terminal, lexical search is carry out in server processing system. feature vector of speech signal extract using GMM a phoneme execution, recognition a phoneme list transmission server using Lexical Tree Search algorithm lexical search recognition execution. System performance as a result of represent vocabulary dependence recognition rate of 98.01%, vocabulary independence recognition rate of 97.71%, represent recognition speed of 1.58 second.

• Phonetics and Speech Sciences
• /
• v.1 no.2
• /
• pp.3-8
• /
• 2009

In an effort to improve speech recognition, we investigated the effect of the number of clusters. In usual LBG clustering, the number of codebook clusters is doubled on each bifurcation and hence cannot be chosen arbitrarily in a natural way. To have the number of clusters at our control, we combined adaptive resonance theory (ART2) with LBG and perform the clustering in two stages. The codebook thus formed was used in subsequent processing of fuzzy vector quantization (FVQ) and HMM for speech recognition tests. Compared to conventional LBG, our method was shown to reduce the best recognition error rate by 0${\sim$}0.9% depending on the vocabulary size. The result also showed that between 400 and 800 would be the optimal number of clusters in the limit of small and large vocabulary speech recognitions of isolated words, respectively.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1705-1709
• /
• 2005

This paper covers review and challenges in the area of speech recognition by taking into account different classes of recognition mode. The recognition mode can be either speaker independent or speaker dependant. Size of the vocabulary and the input mode are two crucial factors for a speech recognizer. The input mode refers to continuous or isolated speech recognition system and the vocabulary size can be small less than hundred words or large less than few thousands words. This varies according to system design and objectives.[2]. The organization of the paper is: first it covers various fundamental methods of speech recognition, then it takes into account various deficiencies in the existing systems and finally it discloses the various probable application areas.

• Korean Institute of Interior Design Journal
• /
• v.22 no.2
• /
• pp.58-67
• /
• 2013

The methods used in this study included investigation of media facades used for landmarks in downtown areas in previous studies, visits to these areas, and recording of media facades. The changes in the colors or the size of buildings were analyzed among the recorded cases and 12 of these cases were selected for further study. The sensibility preference of the media facades was evaluated by sorting the 12 kinds of media facades, and providing them as materials to a group of 60 participants (40 undergraduate and 20 graduate students majoring in architecture and design) consisting of an equal proportion of males and females. This study addressed the following four_stage questions: 1) Five questions of recognition evaluation about media facades and the cognitive evaluation items of emotional vocabulary and color preference in each research case; 2) sensibility preference items regarding the media facade color design; and 3) design evaluation items of the media facades; 4) Video clips and still images were recorded from a middle distance at 7p.m to 11p.m. in central New York, Singapore, Seoul, and Beijing. The participants looked at the changes in colors through the video clips in each case and evaluated their preferences through 23 pairs of emotional vocabulary items using system dynamics. Construction of an emotional vocabulary followed, based on previous studies about media facades and color design. To evaluate the sensibility preference and the perceived representative colors of the media facade, this study suggests new emotional responses that depended on the color emotional vocabulary of light in the LED lighting technical evaluation methodology. A media facade with a moving change of colors, unlike a fixed landscape color design, suggests a new communication method based on architectural factors. New architectural color coordination can be presented for urban landscapes at night. Designs that factor in the pedestrians' emotional vocabulary or preference should take precedence over the use of high luminance and various colors.